JP7081665B2 - Image recording method - Google Patents

Description

The present invention relates to an image recording method for forming a printed image on various substrates, and more specifically, to reduce a gloss difference between an image forming portion and a non-image forming portion, and to obtain an image having excellent adhesion and wettability. It relates to the image recording method to form.

Currently, various image recording methods include, for example, an inkjet recording method for forming an image on special paper or textile products using inkjet ink containing dyes and pigments, and an electrophotographic process for toner containing coloring materials. Widely used in various fields such as an electrophotographic method that forms an image by applying and fixing it on a thin film, a screen printing method that forms a pattern on various substrates using printing ink, and an offset printing method. is doing.

Among the above-mentioned image recording fields, the inkjet recording method is used in various printing fields because an image can be formed at low cost by using a simple device.

Further, in recent years, as one of the inkjet recording methods, an active light-curing inkjet ink containing a photocurable compound having a property of being cured by irradiation with active light is used, and the ink droplets of the inkjet ink are used as a base material (hereinafter referred to as "base material"). , Also referred to as a "recording medium") A method of forming an image by irradiating the ink jet ink with active light after landing on the ink jet ink is being actively studied. By using such an active ray-curable inkjet ink, high-quality dots are suppressed from spreading on recording media having various characteristics, including non-absorbent base materials that do not have ink absorbency. It is possible to form an image having high scratch resistance.

On the other hand, in various image recording methods, the gloss of the formed image portion and the gloss of the non-printed area (unprinted portion) of the recording medium are closely matched to correspond to the various uses, and the unprinted portion and the image forming portion are closely matched. It is strongly required to reduce the difference in gloss between the image and the image from the viewpoint of obtaining an image with less discomfort. In particular, in the field of commercial printing, if the gloss of the printed paper surface and the gloss of the printed surface are different, it is perceived as a glossy discomfort, and the commercial value is lowered. There is a strong demand for close matching.

In the inkjet recording method using the above-mentioned active ray-curable inkjet ink, a base layer (also referred to as a primer layer) is required from the viewpoint of adhesion between the base material and the formed image when printing on any base material. There is a base material to be used. However, when the high-gloss base layer is formed on one surface of the base material, the gloss of the base layer is prioritized, and there arises a problem that the glossiness of the base material is impaired. In addition, the gloss of the image formed by the active ray-curable inkjet ink is often relatively low gloss, and the gloss difference from the unprinted portion of the base material provided with the base layer is widened, which gives a feeling of strangeness. It becomes an image.

The following method has been proposed as a method for adjusting the gloss difference between the printed portion and the non-printed portion as described above.

One method of eliminating the difference in gloss is to form an image on a substrate and then provide an overcoat layer on the image layer. For example, in an inkjet recording method, a printed image has gloss. There is a technology to apply an overcoat liquid to an image layer formed by irradiating an active light-curing inkjet ink with active light for the purpose of applying it or making it resistant to external impact. Are known. As an example, a technique for controlling the gloss of an image by using an overcoat liquid containing a gelling agent, a curable monomer, a curable wax and a photoinitiator is disclosed (see, for example, Patent Document 1).

However, in the method of applying the overcoat layer on the image layer as proposed in Patent Document 1, the gloss of the image layer itself is canceled by the configuration, so that the texture of the formed image is lost and the texture of the formed image is lost. When the image layer has a predetermined thickness and high gloss is desired to be exhibited, there is a problem that the relief feeling becomes conspicuous.

As another method for eliminating the gloss difference between the printed portion and the non-printed portion, a method of applying transparent toner or transparent ink in a pixel-by-pixel area together with colored toner or colored ink to adjust gloss is known. ing. In the electrophotographic method, for example, in JP-A-7-266614 and JP-A-11-7174, a transparent toner having a glossiness similar to that of a colored toner is applied as a gloss adjusting material together with a colored toner, and an image region is applied. A method of reducing the difference in gloss by aligning the heights of the images in the above is disclosed. Further, in the inkjet recording method, a method of suppressing gloss unevenness by using a transparent ink together with a colored ink and adjusting the amount of the transparent ink applied based on the ejection amount of the colored ink is disclosed (for example, a patent). See Document 2).

However, the method disclosed above is a method of applying transparent toner or transparent ink, which is a gloss adjusting material, on a pixel-by-pixel basis. There is a problem that the relative density of the color image formed by the toner or the colored ink is lowered, and it becomes difficult to obtain a uniform feeling as the whole image.

Japanese Unexamined Patent Publication No. 2010-000792 Japanese Unexamined Patent Publication No. 2011-0370115

The present invention has been made in view of the above problems and situations, and the solution thereof is to reduce the gloss difference between the image forming portion and the non-image forming portion, and to form an image having excellent adhesion and wettability. Is to provide an image recording method.

In order to solve the above problems, the present inventor provides a gloss adjusting layer between the base material and the image recording layer when recording images on various base materials in the process of examining the cause of the above problems. This improves the adhesion between the substrate and the image recording layer, measures the glossiness G1 of the image recording layer in advance, and optimizes the glossiness G2 of the gloss adjustment layer based on the measured glossiness G1 information. We have found that it is possible to provide an image recording method that reduces the difference in gloss between the printed portion and the non-printed portion and forms an image without a sense of discomfort by adjusting the conditions, and has arrived at the present invention.
It is a thing.

That is, the above-mentioned problem of the present invention is solved by the following means.

1. 1. An image recording method in which a gloss adjustment layer is provided on a base material and an image recording layer is formed on the gloss adjustment layer.
An image characterized in that the 60-degree mirror gloss G1 of the image recording layer is measured in advance, and the 60-degree mirror gloss G2 of the gloss adjusting layer is adjusted according to the obtained information of the 60-degree mirror gloss G1. Recording method.

2. 2. The glossiness difference ΔG (G2-G1) between the 60-degree mirror surface gloss G2 of the gloss adjustment layer and the 60-degree mirror surface gloss G1 of the image recording layer is within the range of −20 to +20. The image recording method according to paragraph 1.

3. 3. The glossiness difference ΔG (G2-G1) between the 60-degree mirror surface gloss G2 of the gloss adjustment layer and the 60-degree mirror surface gloss G1 of the image recording layer is within the range of −10 to +5. The image recording method according to paragraph 1 or 2.

4. The gloss adjusting layer is formed by a wet coating method using a coating liquid for forming a gloss adjusting layer containing the following component (2) in the range of 0.1 to 20% by mass with respect to the following component (1). The image recording method according to any one of the features 1 to 3.

Component (1): Resin dispersion using an aqueous solvent as a dispersion medium Component (2): Organic or inorganic fine particles having an average particle size in the range of 1.0 to 20 μm 5. The image recording method according to item 4, wherein the wet coating method is an inkjet printing method.

6. The image recording method according to any one of items 1 to 5, wherein the image recording layer is formed of an active light curable inkjet ink.

7. The image recording method according to any one of items 1 to 6, wherein the image recording layer is formed of an active photocurable inkjet ink containing a gelling agent.

8. The gelling agent contains any one of the compounds having a structure represented by the following general formula (G1) or (G2) in an amount of 0.1 to 5.0% by mass based on the total mass of the active photocurable inkjet ink. Contains within the range of
Moreover, the photopolymerizable compound is contained in the range of 10 to 40% by mass of the total mass of the active photocurable inkjet ink, the photopolymerizable compound has a molecular weight in the range of 280 to 1500, and the ClogP value is. The image recording method according to Item 7, wherein the acrylate compound is in the range of 4.0 to 7.0.

General formula (G1): R ₁ -CO-R ₂
General formula (G2): R ₃ -COO-R ₄
[In the formula, R ₁ to R ₄ each independently represent a linear or branched alkyl group having a carbon number in the range of 12 to 26. ]
9. The average particle size r of the organic or inorganic fine particles contained in the gloss adjusting layer is set in the range of 1.5 to 7.0 μm, and the film thickness hd after drying is set in the range of 1.0 to 3.0 μm.
Items 4 to 8 are characterized in that the film thickness hd after drying of the gloss adjusting layer and the average particle size r of the organic or inorganic fine particles satisfy the conditions specified by the following formula (1). The image recording method according to any one of the above.

Equation (1)
Film thickness after drying of the gloss adjusting layer hd <average particle size of organic or inorganic fine particles r
10. The image recording method according to any one of items 4 to 9, wherein the resin dispersion contained in the gloss adjusting layer contains a resin containing an acrylic component.

11. The image recording method according to any one of items 4 to 10, wherein the organic fine particles contained in the gloss adjusting layer are acrylic fine particles.

According to the present invention, it is possible to provide an image recording method that reduces the difference in gloss between an image forming portion and a non-image forming portion and forms an image having excellent adhesion and wettability.

Although the mechanism of effect manifestation or mechanism of action of the image recording method having the configuration specified in the present invention has not been clarified, it is inferred as follows.

When image formation is performed on various base materials (recording media) having various surface characteristics (for example, surface glossiness, uneven structure, adhesion characteristics, etc.), the image forming layer and the base material depend on the characteristics of the base material. In many cases, the image becomes uncomfortable due to the decrease in adhesion between the images and the difference in glossiness between the image forming portion which is the printed portion and the base material which is the non-printed portion. To solve the above problems, there are a method of providing an overcoat layer after image recording to reduce the difference in glossiness and a method of smoothing using transparent toner or transparent ink, but both methods increase the man-hours and increase the cost. In addition, the effect of reducing the difference in gloss with respect to various substrates is not sufficient, and there is a problem in terms of versatility.

In the present invention, as a result of diligent studies based on the above problems, in the image recording method for forming an image recording layer on a base material, the gloss between the image forming portion and the base material portion which is a non-image forming portion is obtained. In order to reduce the difference, by providing a gloss adjustment layer designed to match the glossiness of the image recording layer between the base material and the image recording layer, image formation that could not be achieved by the prior art can be achieved. By making the best use of the texture of the part, we were able to realize an image formation that has a natural and natural luster on the entire surface. In particular, it has been found that the glossiness of the gloss adjusting layer can be made possible by appropriately adjusting the average particle size and the amount of the added amount of the inorganic or organic fine particles to be applied.

Further, in the image recording method having the configuration specified in the present invention, by providing the gloss adjusting layer between the base material and the image recording layer, the adhesion between the two and the coloring material used for forming the layer recording layer can be obtained. By improving the applicability of the contained ink liquid and the like, it was possible to achieve an improvement in image quality.

The design concept of applying the gloss adjustment layer of the present invention and adjusting the glossiness of the gloss adjustment layer according to the glossiness of the image forming portion is completely new, and is not limited to a typical inkjet recording method. It can also be widely used in the printing fields such as the electrophotographic method, the widely used screen printing method, and the offset printing method.

Among them, it is effective to apply it to the inkjet recording method, and it is more effective in the inkjet recording method using the active light curable inkjet ink, and further, the active light curable inkjet ink containing a gelling agent is used. By applying it to the inkjet recording method used, oxygen inhibition on the surface of the image recording layer is prevented, so that the ink is uniformly cured by irradiation with active light, the strength of the image forming film is increased, and the adhesion is further improved. Can be improved.

Schematic cross-sectional view showing an example of the configuration of an image recording material in which an image recording layer is formed on a substrate having a gloss adjustment layer. A flow chart showing an example of an image forming process by the image recording method of the present invention. Schematic cross-sectional view showing an example of the configuration of the gloss adjusting layer according to the present invention. A side view showing an example of a single-pass recording type inkjet recording device applicable to an inkjet recording method using active ray-curable inkjet ink. Top view showing an example of a single-pass recording type inkjet recording device applicable to an inkjet recording method using active ray-curable inkjet ink. Top view showing an example of a serial recording type inkjet recording device applicable to an inkjet recording method using active ray curable inkjet ink.

The image recording method of the present invention is an image recording method in which a gloss adjustment layer is provided on a base material and an image recording layer is formed on the gloss adjustment layer. It is characterized in that the 60-degree mirror surface gloss G2 of the gloss adjusting layer is adjusted according to the measured and obtained information of the 60-degree mirror surface gloss G1. This feature is a technical feature common to the inventions according to each of the following embodiments. In the embodiment of the present invention, the 60-degree mirror gloss of the gloss adjusting layer can be more exhibited from the viewpoint of further exhibiting the effect intended by the present invention. The glossiness difference (G2-G1) between the degree G2 and the 60-degree mirror glossiness G1 of the image recording layer shall be within the range of -20 to +20, and the glossiness difference (G2-G1) shall be -10 to 10. It is preferable that the range is within the range of +5 in that the gloss difference between the image forming portion and the non-image forming portion can be further reduced and an image without a sense of discomfort can be formed.

Further, the gloss adjusting layer is wetted by using a coating liquid for forming a gloss adjusting layer containing organic or inorganic fine particles in a specific particle size range in the range of 0.1 to 20% by mass with respect to the resin dispersion. It is preferable that the glossiness of the gloss adjusting layer can be adjusted to a desired 60-degree mirror surface glossiness G2 by forming by a coating method and further applying an inkjet printing method as a wet coating method.

Further, forming the image recording layer by using an active ray-curable inkjet ink has excellent adhesion to the gloss adjusting layer, suppresses the wetting and spreading of dots, and has high quality and high scratch resistance. It is preferable in that an image can be obtained.

Further, forming the image recording layer with an active photocurable inkjet ink containing a gelling agent prevents oxygen inhibition on the formed recorded image surface, and the general formula (G1) or ( Any one of the compounds having the structure represented by G2) is contained within the range of 0.1 to 5.0% by mass of the total mass of the active photocurable inkjet ink, and as a photopolymerizable compound. It is the object effect of the present invention to contain an acrylate compound having a molecular weight in the range of 280 to 1500 and a ClogP value in the range of 4.0 to 7.0 in the range of 10 to 40% by mass. It is preferable in that it can be more expressed.

Further, the average particle size r of the organic or inorganic fine particles contained in the gloss adjusting layer is set in the range of 1.5 to 7.0 μm, and the film thickness hd after drying is set in the range of 1.0 to 3.0 μm. Further, by designing so that the average particle size r of the organic or inorganic fine particles is larger than the dried film thickness hd of the gloss adjustment layer, the 60 degree mirror glossiness G2 of the gloss adjustment layer is a desired condition. It is a more preferable embodiment in that it can be set to.

Further, it is the object effect of the present invention that the resin dispersion contained in the gloss adjusting layer is a resin containing an acrylic component, or the organic fine particles contained in the gloss adjusting layer are acrylic fine particles. It is preferable in that it can be expressed.

Hereinafter, the present invention, its constituent elements, and modes and embodiments for carrying out the present invention will be described. In addition, in this application, "-" is used in the sense that the numerical values described before and after it are included as the lower limit value and the upper limit value. Further, in the description using the following figures, the numbers in parentheses after each component represent the code of each component described in each figure.

<< Image recording method >>
The image recording method of the present invention is an image recording method in which a gloss adjustment layer is provided on a base material and an image recording layer is formed on the gloss adjustment layer. G1 is measured by the method described below, and the 60-degree mirror surface gloss G2 of the gloss adjusting layer is adjusted according to the obtained information of the 60-degree mirror surface gloss G1 to record an image. It is characterized by doing.

FIG. 1 is a schematic cross-sectional view showing an example of the configuration of an image recording material in which an image recording layer is formed on a base material having a gloss adjusting layer.

The image recording material (1) formed by the image recording method of the present invention is adjusted to a glossiness G2 (G2) on the base material (2) according to the glossiness G1 (G1) of the image forming layer (4). The gloss adjustment layer (3) is provided on the entire surface, and an image forming material, for example, inkjet ink is emitted onto the entire surface or a specific area according to the pattern of the formed image to form an image. Is a way to do.

FIG. 2 shows a process flow of image formation by the image recording method of the present invention.

Step 1: First, a solid image of the image recording layer is formed on the substrate, and a sample of the layer recording layer single layer for measuring the glossiness of the image recording layer is prepared.

Step 2: For the solid image of the layer recording layer produced above, the 60-degree surface gloss G1 is measured according to the method specified in JIS Z 8741.

Step 3: According to the information of the 60-degree surface gloss G1 of the layer recording layer obtained above, the 60-degree surface gloss G2 of the gloss adjusting layer is set. At this time, the glossiness difference ΔG (G2-G1) between the 60-degree surface glossiness G2 of the gloss adjustment layer and the 60-degree surface glossiness G1 of the layer recording layer is preferably in the range of −20 to +20, more preferably. The composition of the gloss adjusting layer is appropriately adjusted so as to be in the range of −10 to +5.

In the present invention, the most effective method for adjusting the glossiness of the gloss adjusting layer is to average the gloss adjusting layer with at least a resin dispersion having an aqueous solvent as a dispersion medium as the component (1) and the component (2). Formation of a gloss adjustment layer composed of organic or inorganic fine particles having a particle size in the range of 1.0 to 20 μm and containing the following component (2) in the range of 0.1 to 20% by mass with respect to the component (1). By forming with a coating liquid for use, a gloss adjusting layer having a desired 60-degree surface gloss G2 can be obtained. That is, the type, particle size, and addition amount of the organic or inorganic fine particles are appropriately adjusted with respect to the resin dispersion having a high glossiness, and the composition of the coating liquid for forming the gloss adjusting layer for adjusting the desired glossiness is determined. do.

More preferably, the average particle size r of the organic or inorganic fine particles is set to be larger than the thickness hd after drying of the gloss adjusting layer, that is, the upper surface of the organic or inorganic fine particles is exposed on the surface of the gloss adjusting layer. Therefore, it is preferable to form an uneven structure.

Step 4: The gloss adjusting layer forming coating liquid whose composition is determined in step 3 is applied onto the substrate by an inkjet printing method or a wet coating method to form a gloss adjusting layer.

Step 5: Finally, an image recording layer having the same configuration as described in step 1 is formed.

[60 degree mirror gloss]
The 60-degree mirror glossiness referred to in the present invention is a value measured according to the measuring method specified in JIS Z 8741. Examples of the measuring device that can be used for measuring the 60-degree mirror gloss according to the present invention include a precision gloss meter GM-26D, a True Gloss GM-26DPRO, and a variable angle gloss meter GM-3D (above, Murakami Color Technology Research). Specified angle gloss meter VGS-10001DP (manufactured by Nippon Denshoku Kogyo Co., Ltd.), digital variable angle gloss meter (Suga Test Instruments Co., Ltd.) and the like. In the present invention, the values measured using the variable angle gloss meters PG-1M and VGS-10001DP (manufactured by Nippon Denshoku Kogyo Co., Ltd.) are applied.

<< Each component >>
Next, the details of each component applied to the pixel recording method of the present invention will be described.

〔Base material〕
The base material applicable to the image recording method of the present invention is not particularly limited as long as it can stably hold the gloss adjustment layer and the image recording layer formed on the base material, but is 60 degrees of the gloss adjustment layer. It is preferable that the base material has a glossiness that does not significantly deviate from the surface glossiness G2.

Examples of the base material applicable to the present invention include plain paper used for copying and the like, paper base materials such as art paper, ordinary uncoated paper, and a coat in which both sides of the base paper are coated with resin or the like. In addition to paper, various laminated papers, synthetic papers, etc., various non-absorbent plastics used for so-called flexible packaging and their films can be used. Examples of various plastic films include polyethylene terephthalate (PET) and stretched polystyrene. (OPS), stretched polypropylene (OPP), stretched nylon (ONy), polyvinyl chloride (PVC), polyethylene (PE), triacetyl cellulose (TAC) film can be mentioned. As other plastics, polycarbonate (PP), acrylic resin, ABS resin, polyacetal, PVA, rubber and the like can be used. It can also be applied to metals and glasses. Among the above base materials, a plastic film is preferable.

Examples of plain paper applicable to the present invention include high-grade printing paper, intermediate-grade printing paper, low-grade printing paper, light-weight printing paper, finely coated printing paper, special printing paper such as high-quality color paper, foam paper, and PPC paper ( Copy paper), other information paper, etc.

Also, as art papers, for example, OK Kanto N, Satin Kanto N, SA Kanto, Ultra Satin Kanto N, OK Ultra Aqua Satin, OK Kanto One-sided, N Art Post, NK Special Double-sided Art, Raicho Super Art N, Raicho Super Art MN, Thunderbird Art N, Thunderbird Dal Art N and the like can be mentioned.

The coated paper includes, for example, POD gloss coat, OK top coat +, OK top coat S, aurora coat, mu coat, mu white, thunderbird coat N, Utrilo coat, pearl coat, white pearl coat, POD matte coat, and the like. Examples include New Age, New Age W, OK Top Coat Mat N, OK Royal Coat, and OK Top Coat Dal.

《Gloss adjustment layer》
The gloss adjusting layer according to the present invention is coated with a coating liquid for forming a gloss adjusting layer containing the following component (2) in a range of 0.1 to 20% by mass with respect to the following component (1) by an inkjet printing method or a wet coating method. It is preferably formed by the method.

Component (1): Resin dispersion using an aqueous solvent as a dispersion medium Component (2): Organic or inorganic fine particles having an average particle size in the range of 1.0 to 20 μm.

Hereinafter, the details of the resin dispersion, the inorganic fine particles, and the organic fine particles constituting the gloss adjusting layer will be described.

[Resin dispersion]
The resin dispersion (hereinafter, also referred to as resin emulsion or polymer latex) constituting the component (1) refers to a water-insoluble hydrophobic polymer dispersed in water or a water-soluble dispersion medium as fine particles. As a dispersed state, the polymer is emulsified in a dispersion medium, emulsion-polymerized, micelle-dispersed, or has a partially hydrophilic structure in the polymer molecule and the molecular chain itself is molecularly dispersed. Anything may be used. For polymer latex, see "Synthetic Resin Emulsion (edited by Taira Okuda and Hiroshi Inagaki, published by Polymer Publishing Association (1978))", "Application of Synthetic Latex (Takaaki Sugimura, Yasuo Kataoka, Soichi Suzuki, edited by Keiji Kasahara, Polymer)" It is described in "Published by the Society of Publications (1993))", "Chemistry of Synthetic Latex (written by Soichi Muroi, published by the Society of Polymer Publishing (1970))", and these can be referred to.

Examples of the main skeleton of the polymer dispersible in an aqueous solvent include polyethylene, polyethylene-polyvinyl alcohol (PVA), polyethylene-polyacetate vinyl, polyethylene-polyurethane, polybutadiene, polybutadiene-polystyrene, polyolefin copolymer, and polyamide (nylon). , Polyvinylidene chloride, polyester, polyacrylate, polyacrylate-polyester, polyacrylate-polystyrene, polyvinyl acetate, polyurethane-polycarbonate, polyurethane-polyether, polyurethane-polyethane, polyurethane-polyacrylate, silicone, silicone-polyurethane, silicone- Examples thereof include polyacrylate, polyvinylidene fluoride-polyacrylate, polyfluoroolefin-polyvinyl ether and the like. Further, a copolymer using these skeletons as a base and further using other monomers may be the main skeleton. Among these, a polyester resin emulsion having an ester skeleton, an acrylic resin emulsion, a polyester-acrylic resin emulsion, a vinyl chloride-acrylic resin copolymer emulsion, and a polyethylene resin emulsion having an ethylene skeleton are preferable, and in particular, an acrylic component is contained. A resin emulsion is preferable in that the objective effect of the present invention can be more exhibited.

Commercially available products include Polysol FP3000 (polyester resin, anion, core: acrylic, shell: polyester, manufactured by Showa Denko), Vironal MD1480 (polyester resin, anion, manufactured by Toyo Spinning Co., Ltd.), Vironal MD1245 (polyester resin, anion, manufactured by Toyo Spinning Co., Ltd.). , Vironal MD1500 (polyester resin, anion, manufactured by Toyo Spinning Co., Ltd.), Vironal MD2000 (polyester resin, anion, manufactured by Toyo Spinning Co., Ltd.), Vironal MD1930 (polyester resin, anion, manufactured by Toyo Spinning Co., Ltd.), Plus Coat RZ105 (polyester resin, anion). , Made by Reciprocal Chemical Co., Ltd.), Plus Coat RZ570 (polyester resin, anion, manufactured by Reciprocal Chemical Co., Ltd.), Plus Coat RZ571 (polyester resin, anion, manufactured by Reciprocal Chemical Co., Ltd.), Elitel (manufactured by Unitica), Byron (manufactured by Toyo Spinning Co., Ltd.) Polyester resin such as Evaflex (manufactured by Mitsui / Dupont Polychemical), ethylene-vinyl acetate copolymer resin, butyral resin such as Eslek (manufactured by Sekisui Chemical Co., Ltd.), Byron UR (manufactured by Toyo Spinning Co., Ltd.), NT-High Ramic (Manufactured by Dainichi Seika Co., Ltd.), Chris Bonn (manufactured by Dainippon Ink and Chemicals Co., Ltd.), Nippon Polyester (manufactured by Nippon Polyester Co., Ltd.), etc. ), Saran Latex (manufactured by Asahi Kasei Chemicals), Sumi Elite (manufactured by Sumitomo Chemical Co., Ltd.), Sekisui PVC (manufactured by Sekisui Chemical Co., Ltd.), UCAR (manufactured by Dow Chemical Co., Ltd.), etc. , Anion, Polyester resin such as Toho Kagaku Co., Ltd., Movinyl 7720 (Acrylic resin, Nonion, manufactured by Nippon Synthetic Chemical Co., Ltd.), Movinyl 7820 (Acrylic resin, Nonion, manufactured by Nippon Synthetic Chemical Co., Ltd.), John Krill (Johnson Polymer Co., Ltd.) , Eslek P (manufactured by Sekisui Chemical Co., Ltd.), MFR1924 (manufactured by Michelman), Polytron (manufactured by Asahi Kasei Co., Ltd.), Nipol series (manufactured by ZEON), and other acrylic resins can be used. Further, the polymer dispersible in the aqueous solvent may contain one kind of the above-mentioned polymer, or may contain a plurality of kinds thereof.

The aqueous solvent applicable to the resin dispersion includes not only pure water (including distilled water and deionized water), but also an aqueous solution containing an acid, an alkali, a salt, etc., a water-containing organic solvent, or a hydrophilic organic solvent. It is a solvent. Examples of the water-based solvent include pure water (including distilled water and deionized water), alcohol-based solvents such as methanol and ethanol, and mixed solvents of water and alcohol.

The average particle size of the dispersed particles of the resin dispersion according to the present invention is not particularly limited, but is preferably in the range of 5 to 200 nm. When the average particle size is 5 nm or more, aggregation of particles can be suppressed, dispersion stability can be improved, and smoothness of the coated surface can be improved. Further, when the average particle size is 200 nm or less, haze of the gloss adjusting layer can be suppressed, and suitable performance as an image forming unit (base material / gloss adjusting layer / image forming layer) to be formed can be obtained.

Further, in the gloss adjusting layer according to the present invention, as described above, the average particle size r of the organic or inorganic fine particles contained in the gloss adjusting layer is set in the range of 1.5 to 7.0 μm, and the film thickness after drying is hd. Is in the range of 1.0 to 3.0 μm, and the thickness hd after drying of the gloss adjusting layer and the average particle size r of the organic or inorganic fine particles satisfy the conditions specified by the following formula (1). Is a preferred embodiment.

Equation (1)
Film thickness after drying of the gloss adjusting layer hd <average particle size of organic or inorganic fine particles r
FIG. 3 is a schematic cross-sectional view showing an example of the configuration of the gloss adjusting layer according to the present invention.

As shown in FIG. 3, in the gloss adjusting layer (3) formed on the base material (2), the film thickness of the gloss adjusting layer (3) formed mainly by the resin dispersion which is a binder is defined as hd. When the average particle size of the organic or inorganic fine particles (5) contained in is r, the condition that each particle size is r> hd is satisfied, and the surface of the gloss adjusting layer (3) is organic or inorganic. The upper part of the fine particles (5) is exposed to form a convex structure, and the density of the convex structure or the height of the convex structure is controlled to control the glossiness G2 of the gloss adjusting layer to a desired characteristic. be able to.

The value of the ratio of the average particle size r of the organic or inorganic fine particles / the film thickness hd of the gloss adjusting layer is 1.01 or more, preferably 1.01 to 2.6, and more preferably 1.4. It is within the range of ~ 2.1.

[Fine particles]
In the gloss adjusting layer according to the present invention, organic or inorganic fine particles having an average particle size in the range of 1.0 to 20 μm defined by the component (2) are mixed with respect to the resin dispersion which is the component (1). It is preferably contained in the range of 0.1 to 20% by mass.

The average particle size as used in the present invention means the primary average particle size, and can be measured from an electron micrograph taken by a scanning electron microscope (SEM) or the like. It may be measured by a particle size distribution meter or the like using a dynamic light scattering method, a static light scattering method, or the like.

When determined from an electron microscope, the average particle size of the primary particles is determined by observing the particles themselves or the particles appearing on the cross section or surface of the gloss adjusting layer with an electron microscope and measuring the particle size of 1000 arbitrary particles. It is obtained as the simple average value (number average). Here, the particle size of each particle is expressed by the diameter assuming a circle equal to the projected area.

[Inorganic fine particles]
Examples of the inorganic fine particles applicable to the gloss adjusting layer according to the present invention include SiO ₂ , Al ₂ O ₃ , TiO ₂ , SnO ₂ , Sb ₂ O ₅ , Fe ₂ O ₃ , ZrO ₂ , CeO ₂ , and Y ₂ . Inorganic fine particles such as O ₃ can be mentioned.

As commercially available inorganic fine particles, for example, as silica particles, functional spherical silica HPS series (manufactured by Toa Synthetic Co., Ltd.), "Seahoster" KE series (manufactured by Nippon Catalyst Co., Ltd.), "particle size standard particles" 8000 series (manufactured by Nippon Catalyst Co., Ltd.) As alumina particles, "alumina spherical fine particles" series (Nittetsu Materials Co., Ltd.) such as Thermo Fisher Scientific), "Admafine" series (manufactured by Admatex Co., Ltd.), "High Presica" series (manufactured by Ube Nitto Kasei Co., Ltd.), etc. Micron), "Admafine" series (Admatex Co., Ltd.), "Alumina" series (Nippon Light Metal Co., Ltd.), "Alumina beads" CB series (Showa Denko Co., Ltd.), etc. Can be done. Among these, silica particles are preferable, and examples thereof include Seahoster KE-P100 (average particle size: 1.0 μm) and KE-P150 (average particle size: 1.5 μm) manufactured by Nippon Shokubai Co., Ltd.

[Organic fine particles]
Examples of the organic fine particles applicable to the gloss adjusting layer according to the present invention include acrylic resin particles such as polyacrylate particles and polymethacrylate particles, polyamide resin particles such as nylon particles, and polyolefin particles such as polyethylene particles and polypropylene particles. Examples thereof include spherical resin particles made of a generally known resin such as resin particles, silicone-based resin particles, phenol-based resin particles, polyurethane-based resin particles, styrene-based resin particles, and benzoguanamine resin particles.

These organic fine particles are also available as commercial products. Examples of the acrylic resin fine particles include Chemisnow MX-300 (average particle size: 3 μm) and MX-500 as acrylic resin fine particles manufactured by Soken Kagaku Co., Ltd. (Average particle size: 5 μm), MX-1000, MX-1500H, MR-2HG, MR-7HG, MR-10HG, MR-3GSN, MR-5GSN, MR-7G, MR-10G, MR-5C, MR- 7GC (average particle size: 6 μm), as acrylic resin fine particles manufactured by Sekisui Chemical Co., Ltd., MBX-5, MBX-8, MBX-12MBX-15, MBX-20, MB20X-5, MB30X-5, MB30X-8, MB30X As polystyrene resin fine particles manufactured by Sekisui Chemical Co., Ltd., such as -20, SBX-6, SBX-8, SBX-12, SBX-17, etc., Chemipearl W100, W200, W300, W308, W310, which are polyolefin resin fine particles manufactured by Mitsui Chemicals, Inc. , W400, W401, W405, W410, W500, WF640, W700, W800, W900, W950, WP100 and the like.

The nylon particles include SP-500 (average particle size: 5 μm), SP-10 (average particle size: 10 μm), TR-1 (average particle size: 13 μm), and TR-2 (average particle size) manufactured by Toray Industries, Inc. Diameter: 20 μm) and the like.

[Method of forming the gloss adjustment layer]
The coating liquid for forming the gloss adjusting layer used for forming the gloss adjusting layer according to the present invention has a resin dispersion using an aqueous solvent as a dispersion medium as the component (1) and an average particle size of 1.0 to the component (2). It is a preferable embodiment to contain organic or inorganic fine particles within the range of 20 μm, but the preparation method thereof is not particularly limited, but there is no aggregation of organic or inorganic fine particles, and a coating for forming a gloss adjusting layer having a uniform composition is applied. From the viewpoint of preparing a liquid, as a first step, organic or inorganic fine particles are added little by little to a dispersion solvent, for example, isopropanol (abbreviation: IPA) with stirring, and the fine particles are aggregated. It is preferable to take a method of preparing a coating liquid for forming a gloss adjusting layer by adding a resin dispersion after maintaining a stable state.

In the present invention, the gloss adjusting layer is preferably formed by a wet coating method using a coating liquid for forming a gloss adjusting layer containing each of the components described above, and more preferably, an inkjet print is used as the wet coating method. It is preferable to apply the method.

Antioxidants, ultraviolet absorbers, plasticizers, surfactants and the like can be added to the coating liquid for forming the gloss adjusting layer, if necessary.

Examples of the wet coating method applicable to the present invention include a spin coating method, a casting method, a screen printing method, a die coating method, a blade coating method, a roll coating method, a spray coating method, a curtain coating method, and an LB method (Langmuir-bro). The jet method), the inkjet printing method, and the like are mentioned, and it is particularly preferable to apply the inkjet printing method from the viewpoint of easy to obtain a uniform thin film and high productivity.

The details of the inkjet printing method using the inkjet recording head will be described later.

《Image recording layer》
Next, the details of the layer recording layer will be described.

The image recording layer using the image recording method of the present invention includes, for example, an inkjet recording method using inkjet ink as an image forming material, and a color toner containing a coloring material on paper or a thin film by an electrophotographic process. It can be applied to an electrophotographic method for applying and fixing to form an image, a screen printing method for forming a pattern or the like on various base materials using printing ink, an offset printing method, etc. , It is preferable to apply it to an inkjet recording method using an inkjet ink.

Hereinafter, a method of forming an image recording layer using inkjet ink will be described.

As the inkjet ink, water-based inkjet ink (dye type, pigment type), solvent ink, active light-curing inkjet ink, solid-state inkjet ink (hot melt ink) and the like are widely used. It is preferable to form the image recording layer according to the invention by using an active photocurable inkjet ink containing a photopolymerizable compound.

Hereinafter, an active photocurable inkjet ink (hereinafter, also referred to as an active photocurable ink, a UV curable ink, or simply an ink) suitable as a method for forming an image recording layer using a typical inkjet ink has been applied. The details of the method will be described.

[Active ray curable ink]
The active photocurable ink according to the present invention is mainly composed of a coloring material (for example, a pigment, a dye, etc.), a photopolymerizable compound, a photopolymerization initiator, a polymerization inhibitor, and the like.

Further, in the active photocurable ink according to the present invention, it is a preferable embodiment to contain a gelling agent. Hereinafter, details of each component of the active light curable ink according to the present invention will be described.

[Photopolymerizable compound]
The active light curable ink suitable for the present invention preferably contains at least a photopolymerizable compound having a function of being cured by active light.

The photopolymerizable compound may be any of a monomer, a polymerizable oligomer, a prepolymer or a mixture thereof. The ink according to the present invention may contain only one type of photopolymerizable compound, or may contain two or more types of the photopolymerizable compound.

The active ray referred to here is, for example, an energy ray such as an electron beam, an ultraviolet ray, an α ray, a γ ray, and an X-ray, and is preferably an ultraviolet ray or an electron beam. Examples of the photopolymerizable compound include a radically polymerizable compound and a cationically polymerizable compound, and a radically polymerizable compound is preferable.

The content of the photopolymerizable compound is preferably in the range of 1 to 97% by mass with respect to the total mass of the ink according to the present invention, for example, from the viewpoint of film physical properties such as curability and flexibility, and is 30 to 30 to. It is more preferably in the range of 95% by mass.

(Radical polymerizable compound)
The radically polymerizable compound applicable to the present invention is preferably an unsaturated carboxylic acid ester, more preferably a (meth) acrylate.

In the present invention, "(meth) acrylate" means acrylate or methacrylic acid, "(meth) acryloyl group" means acryloyl group or metaacryloyl group, and "(meth) acrylic" means acrylic. Or it means methacrylic.

Examples of (meth) acrylates include isoamyl (meth) acrylate, stearyl (meth) acrylate, lauryl (meth) acrylate, octyl (meth) acrylate, decyl (meth) acrylate, isomilstill (meth) acrylate, isostearyl (meth). Acrylate, 2-ethylhexyl-diglycol (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, Methoxydiethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxypropylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) ) Acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl phthalic acid, 2 -Monofunctional acrylates containing (meth) acryloyloxyethyl-2-hydroxyethyl-phthalic acid and t-butylcyclohexyl (meth) acrylates, triethylene glycol di (meth) acrylates, tetraethylene glycol di (meth) acrylates, Polyethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1 , 9-Nonandiol di (meth) acrylate, neopentyl glycol di (meth) acrylate, dimethylol-tricyclodecandi (meth) acrylate, di (meth) acrylate with bisphenol A structure, neopentyl glycol di hydroxypivalate ( Bifunctional (meth) acrylates, including meth) acrylates, polytetramethylene glycol di (meth) acrylates, polyethylene glycol diacrylates and tripropylene glycol diacrylates, as well as trimethylolpropanetri (meth) acrylates, pentaerythritol tri (meth). ) Glycol, Glycol Trifunctional or higher (meth) acrylates including entaerythritol tetra (meth) acrylates, dipentaerythritol hexa (meth) acrylates, ditrimethylolpropane tetra (meth) acrylates, glycerin propoxytri (meth) acrylates and pentaerythritol ethoxytetra (meth) acrylates. ) Acrylate, an oligomer having a (meth) acryloyl group including a polyester acrylate oligomer, and modified products thereof.

Examples of the modified product include ethylene oxide-modified (EO-modified) acrylate in which an ethylene oxide group is inserted, and propylene oxide-modified (PO-modified) acrylate in which propylene oxide is inserted.

<Acrylate compound A that defines the molecular weight and ClogP value>
In the active photocurable ink according to the present invention, the radically polymerizable compound is a (meth) acrylate compound having a molecular weight in the range of 280 to 1500 and a ClogP value in the range of 4.0 to 7.0. It is preferable to contain (hereinafter, also simply referred to as "(meth) acrylate compound A").

It is more preferable that the (meth) acrylate compound A has two or more (meth) acrylate groups.

The molecular weight of the (meth) acrylate compound A is in the range of 280 to 1500, more preferably in the range of 300 to 800, as described above.

In order to stably eject the ink from the inkjet recording head, the ink viscosity at 80 ° C. can be set to 3 to 20, preferably 7 to 14 mPa · s.

By including a (meth) acrylate compound having a molecular weight of 280 or more and a gelling agent described later in the ink composition, the viscosity of the ink after landing is increased and the penetration of the ink into the recording medium can be suppressed. , The effect of suppressing the decrease in curability can be expected. On the other hand, by containing a (meth) acrylate compound having a molecular weight of 1500 or less, it is possible to suppress an excessive increase in the sol viscosity of the ink, and it is expected that the gloss uniformity of the coating film will be improved.

Here, the molecular weight of the (meth) acrylate compound A can be measured using the following commercially available software package 1 or 2.

Software Package 1: MedChem Software (Released 3.54, August 1991, Medicinal Chemistry Project, Pomona College, Claremont, CA),
Software Package 2: Chem Draw Ultra ver. 8.0. (April 2003, CambridgeSoft Corporation, USA).

In the present invention, when the active light type ink contains the (meth) acrylate compound A as at least a part of the photopolymerizable compound, the (meth) acrylate compound having a ClogP value of less than 4.0 is a photopolymerizable compound. The gloss value tends to be lower than that of the active light curable ink used as. Therefore, when used as an ink for forming an image on a recording medium having a relatively low 60 ° gloss value before the corona discharge treatment, the gloss difference between the printed portion and the non-printed portion can be reduced, which is preferable. Since the (meth) acrylate compound A is more hydrophobic than the (meth) acrylate compound having a ClogP value of less than 4.0, more gelling agents repel and move to the surface of the cured film of the ink, increasing unevenness. As a result, it is considered that the gloss value of the printed portion is lowered. Further, the ClogP value of the (meth) acrylate compound A is more preferably in the range of 4.5 to 6.0.

Here, the "logP value" is a coefficient indicating the affinity of the organic compound for water and 1-octanol.

The 1-octanol / water partition coefficient P is the partition equilibrium when a trace amount of the compound is dissolved as a solute in the solvent of the two-component phase of 1-octanol and water, and is the ratio of the equilibrium concentration of the compound in each solvent. They are shown by their loglogP for the base 10. That is, the "logP value" is a logarithmic value of the partition coefficient of 1-octanol / water, and is known as an important parameter representing the prohydrophobicity of the molecule.

The "LogP value" is a logP value calculated by calculation. The ClogP value can be calculated by a fragment method, an atomic approach method, or the like. More specifically, in order to calculate the ClogP value, the literature (C. Hansch and A. Leo, "Substituts for Partitions for Correlation Analysis in Chemistry and Biology" (John Wiley & Sons, 19), N. The method or the following commercially available software package 1 or 2 may be used.

Software Package 1: MedChem Software (Released 3.54, August 1991, Medicinal Chemistry Project, Pomona College, Claremont, CA),
Software Package 2: Chem Draw Ultra ver. 8.0. (April 2003, CambridgeSoft Corporation, USA).

The numerical value of the "LogP value" referred to in the present invention is the "LogP value" calculated using the software package 2.

The amount of the (meth) acrylate compound A contained in the ink is not particularly limited, but is preferably in the range of 1 to 40% by mass, preferably in the range of 5 to 30% by mass, based on the total mass of the ink. More preferred. By setting the amount of the (meth) acrylate compound A to 1% by mass or more, the ink does not become too hydrophilic and the gelling agent is sufficiently dissolved in the ink, so that the ink easily undergoes a sol-gel phase transition. On the other hand, by setting the amount of the (meth) acrylate compound A to 40% by mass or less, the photopolymerization initiator can be sufficiently dissolved in the ink.

More preferred examples of the (meth) acrylate compound A are (1) trifunctional or higher having 3 to 14 structures represented by (-C (CH ₃ ) H-CH ₂ -O-) in the molecule. It contains a methacrylate or acrylate compound, and (2) a bifunctional or higher functional methacrylate or acrylate compound having a cyclic structure in the molecule. These (meth) acrylate compounds have high photocurability and less shrinkage when cured. Furthermore, the reproducibility of the sol-gel phase transition is high.

A trifunctional or higher methacrylate or acrylate compound having 3 to 14 structures represented by (-C (CH ₃ ) H-CH ₂ -O-) in the molecule includes, for example, 3 or more hydroxy groups. The hydroxy group of the compound is propylene oxide-modified, and the obtained modified product is esterified with (meth) acrylic acid.

Specific examples of this compound include
3PO-modified trimethylolpropane triacrylate Photomer 4072 (molecular weight: 471, ClogP: 4.90, manufactured by Cognis),
3PO-modified trimethylolpropane triacrylate Miramer M360 (molecular weight: 471, ClogP: 4.90, manufactured by Miwon)
Etc. are included.

The bifunctional or higher methacrylate or acrylate compound having a cyclic structure in the molecule is, for example, an esterified hydroxy group of a compound having two or more hydroxy groups and a tricycloalkane with (meth) acrylic acid. ..

Specific examples of this compound include
Tricyclodecanedimethanol diacrylate NK ester A-DCP (molecular weight: 304, ClogP: 4.69),
Tricyclodecanedimethanol dimethacrylate NK ester DCP (molecular weight: 332, ClogP: 5.12)
Etc. are included.

As another specific example of the (meth) acrylate compound A, 1,10-decanediol dimethacrylate NK ester DOD-N (molecular weight: 310, LogP: 5.75, manufactured by Shin-Nakamura Chemical Co., Ltd.) and the like are also included.

The photopolymerizable compound may further contain a photopolymerizable compound other than the (meth) acrylate compound A.

Other photopolymerizable compounds include, for example, (meth) acrylate monomers or oligomers with a ClogP value of less than 4.0, (meth) acrylate monomers or oligomers with a ClogP value greater than 7.0, and other polymerizable properties. There are oligomers and the like.

Examples of these (meth) acrylate monomers or oligomers are 4EO-modified hexanediol diacrylates (CD561, manufactured by Sartomer, molecular weight 358); 3EO-modified trimethylol propantriacrylates (SR454, manufactured by Sartomer, molecular weight 429); 4EO-modified pentaerythritol tetraacrylate (SR494, manufactured by Sartomer, molecular weight 528); 6EO-modified trimethylol propantriacrylate (SR499, manufactured by Sartomer, molecular weight 560); caprolactone acrylate (SR495B, manufactured by Sartomer, molecular weight 344); polyethylene glycol. Diacrylate (NK ester A-400, manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight 508), (NK ester A-600, manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight 708); polyethylene glycol dimethacrylate (NK ester 9G, manufactured by Shin-Nakamura Chemical Co., Ltd.) , Molecular weight 536), (NK ester 14G, manufactured by Shin-Nakamura Chemical Co., Ltd.); Tetraethylene glycol diacrylate (V # 335HP, manufactured by Osaka Organic Chemical Co., Ltd., molecular weight 302); Stearyl acrylate (STA, manufactured by Osaka Organic Chemical Co., Ltd.); EO-modified acrylate (M144, manufactured by Miwon); nonylphenol EO-modified acrylate (M166, manufactured by Miwon) and the like are included.

Examples of other polymerizable oligomers include epoxy acrylates, aliphatic urethane acrylates, aromatic urethane acrylates, polyester acrylates, linear acrylic oligomers and the like.

(Cation-polymerizable compound)
Examples of the cationically polymerizable compound applicable to the present invention include epoxy compounds, vinyl ether compounds, oxetane compounds and the like.

Only one type of the cationically polymerizable compound may be contained in the ink, or two or more types may be contained in the ink.

The epoxy compound is an aromatic epoxide, an alicyclic epoxide, an aliphatic epoxide, or the like, and in order to enhance the curability, the aromatic epoxide and the alicyclic epoxide are preferable.

The aromatic epoxide can be a di or polyglycidyl ether obtained by reacting a polyhydric phenol or an alkylene oxide adduct thereof with epichlorohydrin.

Examples of the polyvalent phenol to be reacted or an alkylene oxide adduct thereof include bisphenol A or an alkylene oxide adduct thereof.

The alkylene oxide in the alkylene oxide adduct may be ethylene oxide, propylene oxide or the like.

The alicyclic epoxide can be a cycloalkane oxide-containing compound obtained by epoxidizing a cycloalkane-containing compound with an oxidizing agent such as hydrogen peroxide or peracid. The cycloalkane in the cycloalkane oxide-containing compound can be cyclohexene or cyclopentene.

The aliphatic epoxide can be a di or polyglycidyl ether obtained by reacting an aliphatic polyhydric alcohol or an alkylene oxide adduct thereof with epichlorohydrin.

Examples of aliphatic polyhydric alcohols include ethylene glycol, propylene glycol, alkylene glycols such as 1,6-hexanediol and the like. The alkylene oxide in the alkylene oxide adduct may be ethylene oxide, propylene oxide or the like.

Examples of vinyl ether compounds include ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, and isopropenyl ether. -O-Polyvinyl ether compounds such as propylene carbonate, dodecyl vinyl ether, diethylene glycol monovinyl ether and octadecyl vinyl ether;
Divinyl ethers such as ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, and trimethylolpropane trivinyl ether. Alternatively, a trivinyl ether compound or the like is included. Among these vinyl ether compounds, di or trivinyl ether compounds are preferable in consideration of curability and adhesion.

The oxetane compound is a compound having an oxetane ring, and examples thereof include the oxetane compounds described in JP-A-2001-220526, JP-A-2001-310937, JP-A-2005-255821, and the like. .. Among them, the compound represented by the general formula (1) described in paragraph number (089) of JP-A-2005-255821 and the compound represented by the general formula (2) described in paragraph number (0092) of JP-A-2005-255821. A compound, a compound represented by the general formula (7) described in paragraph number (0107) of the same publication, a compound represented by the general formula (8) described in paragraph number (0109) of the same publication, the same number. Examples thereof include the compound represented by the general formula (9) described in paragraph number (0116) of the publication.

[Gelling agent]
The active photocurable ink applied to the image recording method of the present invention preferably contains a gelling agent, and the gelling agent is further described by the general formula (G1) or the general formula (G2) described later. It is preferably a compound having the structure represented.

The gelling agent has a function of temporarily fixing (pinning) the ink droplets that have landed on the base material or the gloss adjusting layer in a gel state. When an ink containing a gelling agent is pinned in a gel state, the wet spread of the ink is suppressed and it becomes difficult for adjacent dots to coalesce, so that a higher-definition image can be formed.

The gelling agent preferably crystallizes at a temperature equal to or lower than the gelation temperature of the ink. The gelling temperature is a temperature at which the gelling agent undergoes a phase transition from the sol to the gel when the solized or liquefied ink is cooled by heating, and the viscosity of the ink changes suddenly. Specifically, the solified or liquefied ink is cooled while measuring the viscosity with a viscoelasticity measuring device (for example, MCR300, manufactured by Anton Pearl Co., Ltd.), and the temperature at which the viscosity rises sharply is set to the ink. Can be the gelation temperature of.

When the gelling agent crystallizes in the ink, a structure in which the photopolymerizable compound is contained in the three-dimensional space formed by the gelling agent crystallized in a plate shape, that is, a so-called card house structure is formed. When the card house structure is formed, the liquid photopolymerizable compound is held in the space, so that the ink droplets are less likely to get wet and spread, and the pinning property of the ink is further improved. When the pinning property of the ink is improved, it becomes difficult for the ink droplets that have landed on the recording medium to coalesce with each other, and a higher-definition image can be formed.

In order to form the card house structure, it is preferable that the photopolymerizable compound dissolved in the ink and the gelling agent are compatible with each other.

Examples of gelling agents suitable for forming cardhouse structures include aliphatic ketones, aliphatic esters, petroleum waxes, plant waxes, animal waxes, mineral waxes, hardened castor oil, modified waxes, higher fatty acids, Included are fatty acid amides including higher alcohols, hydroxystearic acid, N-substituted fatty acid amides and specialty fatty acid amides, higher amines, esters of sucrose fatty acids, synthetic waxes, dibenzylidene sorbitol, dimer acid and dimer diol. Among them, aliphatic ketones, aliphatic esters, higher fatty acids, and higher alcohols having hydrocarbon groups in the range of 9 to 25 carbon atoms are preferable from the viewpoint of further enhancing the pinning property. The ink may contain only one type of gelling agent, or may contain two or more types of the gelling agent.

Examples of aliphatic ketones include dilignoceryl ketones, dibehenyl ketones, distearyl ketones, dieicosyl ketones, dipalmityl ketones, dilauryl ketones, dimyristyl ketones, myristyl palmityl ketones and palmityl stearyl ketones. Is done.

Examples of aliphatic esters are fatty acid esters of monoalcohols such as behenyl behenyl, icosyl icosate, and oleyl palmitate; glycerin fatty acid esters, sorbitan fatty acid esters, propylene glycol fatty acid esters, ethylene glycol fatty acid esters and polyoxyethylene fatty acid esters. Etc. contains fatty acid esters of polyhydric alcohols.

Examples of commercially available aliphatic esters include EMALEX series, manufactured by Nippon Emulsion (“EMALEX” is a registered trademark of the company), Rikemar series and Poem series, and RIKEN Vitamin (“Rikemar” and “Poem”). Both are registered trademarks of the same company).

Examples of higher fatty acids include behenic acid, arachidic acid, stearic acid, palmitic acid, myristic acid, lauric acid, oleic acid, and erucic acid.

Examples of higher alcohols include stearyl alcohol and behenyl alcohol.

Among them, in the present invention, as the gelling agent, an aliphatic ketone represented by the following general formula (G1) or an aliphatic ester represented by the following general formula (G2) is particularly preferable.

General formula (G1): R ₁ -CO-R ₂
In the general formula (G1), R ₁ and R ₂ each independently represent an alkyl group containing a linear moiety having a carbon number in the range of 12 to 26 and which may contain a branch.

General formula (G2): R ₃ -COO-R ₄
In the general formula (G2), R ₃ and R ₄ each independently represent an alkyl group containing a linear moiety having a carbon number in the range of 12 to 26 and which may contain a branch.

In the general formulas (G1) and (G2), since the linear or branched hydrocarbon group has 12 or more carbon atoms, the aliphatic ketone represented by the general formula (G1) or the general formula (G2) The crystallinity of the aliphatic ester represented by is further increased, and more sufficient space is created in the above-mentioned card house structure. Therefore, the photopolymerizable compound is easily sufficiently encapsulated in the space, and the pinning property of the ink is further improved. Since the number of carbon atoms of the linear or branched hydrocarbon group is 26 or less, the melting point of the aliphatic ketone represented by the general formula (G1) or the aliphatic ester represented by the general formula (G2) is high. It does not rise excessively and it is not necessary to overheat the ink when it is ejected.

From the viewpoint of increasing the gelation temperature of the ink, gelling the ink more rapidly after landing, and increasing the compatibility with a specific low molecular weight compound, at _least one of _R1 and _R2 or R3 and R At least one of ₄ is preferably a saturated hydrocarbon group in the range of 14 to 22 carbon atoms, and both R ₁ and R ₂ or both R ₃ and R ₄ have carbon atoms in the range of 14 to 22. It is more preferable that it is a saturated hydrocarbon group inside.

Examples of the aliphatic ketone represented by the general formula (G1) include dilignoceryl ketone (carbon number: 23 to 24), dibehenyl ketone (carbon number: 21 to 22), and distearyl ketone (carbon number: 17). ~ 18), Dieicosyl Ketone (Carbons: 19-20), Dipalmityl Ketone (Carbons: 15-16), Dimyristyl Ketone (Carbons: 13-14), Dilauryl Ketone (Carbons: 11) ~ 12), Lauryl myristyl ketone (carbon number: 11-14), Lauryl palmityl ketone (carbon number: 11-16), Myristyl palmityl ketone (carbon number: 13-16), Myristyl stearyl ketone (carbon number: 13) ~ 18), myristylbehenyl ketone (carbon number: 13-22), palmitylstearyl ketone (carbon number: 15-18), balmitylbehenyl ketone (carbon number: 15-22) and stearylbehenyl ketone (carbon number: 17) ~ 22) is included. The number of carbon atoms in parentheses represents the number of carbon atoms of each of the two hydrocarbon groups separated by the carbonyl group.

Examples of commercially available aliphatic ketones represented by the general formula (G1) include 18-Pentriacontanon, manufactured by Alfa Aeser, Hentriacontane-16-on, manufactured by Alfa Aeser, and Kao Wax T-1, manufactured by Kao Corporation. included.

Examples of the aliphatic ester represented by the general formula (G2) include behenyl behenylate (carbon number: 21 to 22), icosyl icosanate (carbon number: 19 to 20), stearyl stearate (carbon number: 17 to 22). 18), palmityl stearate (carbon number: 17 to 16), lauryl stearate (carbon number: 17 to 12), cetyl palmitate (carbon number: 15 to 6), stearyl palmitate (carbon number: 15 to 18) , Myristyl myristate (carbon number: 13-14), cetyl myristate (carbon number: 13-16), octyldodecyl myristate (carbon number: 13-20), stearyl oleate (carbon number: 17-18), Includes stearyl erkaate (21-18 carbon atoms), stearyl linoleate (17-18 carbon atoms), behenyl oleate (18-22 carbon atoms) and arachidyl linoleate (17-20 carbon atoms). .. The number of carbon atoms in parentheses represents the number of carbon atoms of each of the two hydrocarbon groups separated by the ester group.

Examples of commercially available aliphatic esters represented by the general formula (G2) include Unistar M-2222SL and Spalm Aceti, manufactured by NOF CORPORATION (“Unistar” is a registered trademark of the same company), Exepearl SS and Exepearl MY-M. Manufactured by Kao (“Exepearl” is a registered trademark of the company), EMALEX CC-18 and EMALEX CC-10, manufactured by NOF CORPORATION (“EMALEX” is a registered trademark of the company), Amreps PC, manufactured by Higher Alcohol Industry Co., Ltd. (“Amrepus”) Is a registered trademark of the company).

The content of the gelling agent is preferably in the range of 1.0 to 10.0% by mass with respect to the total mass of the ink. By setting the content of the gelling agent to 1.0% by mass or more, the pinning property of the ink can be sufficiently improved and a higher-definition image can be formed. Further, by enhancing the pinning property of the ink, it is possible to suppress insufficient color development due to the ink entering the inside of the recording medium, particularly when an image is formed on a water-absorbent recording medium. By setting the content of the gelling agent to 10.0% by mass or less, the precipitation of the gelling agent from the surface of the formed image can be suppressed, and the ejection property of the ink from the inkjet head is not easily impaired.

The content of the gelling agent is more preferably in the range of 1.0 to 7.0% by mass and preferably in the range of 2.0 to 5.0% by mass with respect to the total mass of the ink. It is more preferably in the range of 2.5 to 4.0% by mass, and most preferably in the range of 2.5 to 4.0% by mass.

[Photopolymerization initiator]
The photopolymerization initiator is a photoradical initiator when the photopolymerizable compound is a radically polymerizable compound, and is a photoacid generator when the photopolymerizable compound is a cationically polymerizable compound.

The ink may contain only one type of photopolymerization initiator, or may contain two or more types of photopolymerization initiator. The photopolymerization initiator may be a combination of both a photoradical initiator and a photoacid generator.

The photoinitiator can be a cleaved radical initiator or a hydrogen abstraction initiator.

Examples of cleaved radical initiators include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 1- (4-isopropylphenyl) -2-hydroxy-2-. Methylpropan-1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) Acetphenone-based initiators containing propane-1-one and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, benzoin-based initiators containing benzoin, benzoin methyl ether and benzoin isopropyl ether, Includes acylphosphine oxide-based initiators, including 2,4,6-trimethylbenzoindiphenylphosphine oxide, benzyl and methylphenylglycoesters.

Examples of hydrogen abstraction-type radical initiators include benzophenone, methyl-4-phenylbenzophenone o-benzoyl benzoate, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, acrylicization. Benzophenone-based initiators, including benzophenone, 3,3', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone and 3,3'-dimethyl-4-methoxybenzophenone, 2-isopropylthioxanthone, 2,4- Thioxanthone-based initiators containing dimethylthioxanthone, 2,4-diethylthioxanthone and 2,4-dichlorothioxanthone, aminobenzophenone-based initiators containing Michlerketone and 4,4'-diethylaminobenzophenone, 10-butyl-2-chloroacryl Includes dong, 2-ethylanthraquinone, 9,10-phenanslenquinone and camphorquinone.

Examples of photoacid generators include the compounds described in Organic Electronics Materials Research Institute, "Organic Materials for Imaging", Bunshin Publishing (1993), pp. 187-192.

The content of the photopolymerization initiator may be in the range where the photopolymerizable compound can be sufficiently cured, and can be, for example, in the range of 0.01 to 10% by mass with respect to the total mass of the ink.

[Other additives]
The active photocurable ink applied to the present invention further contains other components such as a photopolymerization initiator auxiliary agent, a polymerization inhibitor, a polymer dispersant, and a surfactant to the extent that the effects of the present invention can be obtained. You may.

(Photopolymerization initiator auxiliary agent and polymerization inhibitor)
The active photocurable ink applied to the present invention may further contain a photopolymerization initiator auxiliary agent, a polymerization inhibitor and the like, if necessary. The photopolymerization initiator auxiliary agent may be a tertiary amine compound, and an aromatic tertiary amine compound is preferable. Examples of aromatic tertiary amine compounds include N, N-dimethylaniline, N, N-diethylaniline, N, N-dimethyl-p-toluidine, N, N-dimethylamino-p-benzoic acid ethyl ester, Includes N, N-dimethylamino-p-benzoic acid isoamylethyl ester, N, N-dihydroxyethylaniline, triethylamine, N, N-dimethylhexylamine and the like. Of these, N, N-dimethylamino-p-benzoic acid ethyl ester and N, N-dimethylamino-p-benzoic acid isoamyl ethyl ester are preferable. These compounds may be used alone or in combination of two or more.

Examples of polymerization inhibitors include (alkyl) phenol, hydroquinone, catechol, resorcin, p-methoxyphenol, t-butylcatechol, t-butylhydroquinone, pyrogallol, 1,1-picrylhydrazyl, phenothiline, p-benzoquinone. , Nitrosobenzene, 2,5-di-t-butyl-p-benzoquinone, dithiobenzoyl disulfide, picric acid, cuperon, aluminum N-nitrosophenyl hydroxylamine, tri-p-nitrophenylmethyl, N- (3-oxyanilino-) 1,3-Dimethylbutylidene) Aniline oxide, dibutyl cresol, cycloquinone oxime cresol, guayacol, o-isopropylphenol, butyraldoxime, methylethylketoxim, cyclohexanone oxime and the like are included.

(Polymer dispersant)
Examples of the polymer dispersant include hydroxy group-containing carboxylic acid esters, long-chain polyaminoamide and high-molecular-weight acid ester salts, high-molecular-weight polycarboxylic acid salts, long-chain polyaminoamide and polar acid ester salts, and high-molecular-weight unsaturated agents. Acid ester, polymer copolymer, modified polyurethane, modified polyacrylate, polyether ester type anionic activator, naphthalene sulfonic acid formarin condensate salt, aromatic sulfonic acid formalin condensate salt, polyoxyethylene alkyl phosphate, Examples thereof include polyoxyethylene nonylphenyl ether and stearylamine acetate.

Further, as the polymer dispersant, for example, a comb-type block copolymer having a basic group may be used.

The comb-type block copolymer in the comb-type block copolymer having a basic group is graft-polymerized with respect to the linear polymer forming the main chain and the respective structural units derived from the monomers constituting the linear main chain. Refers to a copolymer having another type of polymer.

As the side chain, a long-chain polyoxyalkyl group (EO-PO copolymer group) is preferable. Examples of comb-shaped block copolymers include those in which the main chain is a polymer of acrylic acid ester and the side chain is a long-chain polyoxyalkyl group (EO-PO copolymer group).

The basic group in the comb-type block copolymer having a basic group is preferably a quaternary, tertiary, secondary or primary amine group.

The weight average molecular weight of the polymer dispersant is preferably in the range of 1000 to 50,000, and more preferably in the range of 5000 to 30,000. The weight average molecular weight of the polymer dispersant can be determined by gel permeation chromatography (GPC method) in terms of polystyrene.

Examples of commercially available polymer dispersants containing basic groups include DISPERBYK-109, 161, 168, 180, 2013, 2155, BYKJET-9150 and BYKJET-9151; BASF, manufactured by BASF. , PX4701; PB-821, 822, 824 manufactured by Ajinomoto Fine Techno Co., Ltd .; Solspecerse 24000GR, 32000, 39000, 71000 and J-200 manufactured by Lubrizol, etc. are included. "DISPERBYK" and "BYKJET" are registered trademarks of BYK, "Efka" is a registered trademark of BASF, and "Solspec" is a registered trademark of Lubrizol.

The content of the polymer dispersant is preferably in the range of 30 to 70% by mass with respect to the total mass of the pigment. When the content of the polymer dispersant is 30% by mass or more with respect to the pigment, not only the aggregation of the pigment can be made less likely to occur, but also the interaction between the pigment and the gelling agent can be effectively suppressed. It is possible to further suppress fluctuations in gloss and dot diameter under high temperature storage. When the content of the polymer dispersant is more than 70% by mass with respect to the pigment, the excess polymer dispersant that does not contribute to the pigment dispersion causes gelation inhibition, and the initial gloss value and the initial dot diameter become large. It ends up.

The content of the polymer dispersant is more preferably in the range of 35 to 65% by mass with respect to the total mass of the pigment.

As the polymer dispersant, only one kind may be contained in the inkjet ink of the present invention, or two or more kinds may be contained.

Dispersion of the pigment and the polymer dispersant can be carried out by, for example, a ball mill, a sand mill, an attritor, a roll mill, an agitator, a henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill or a paint shaker.

(Surfactant)
Examples of surfactants include anionic surfactants such as dialkyl sulfosuccinates, alkylnaphthalene sulfonates and fatty acid salts, polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, acetylene glycols and polyoxy. Includes nonionic surfactants such as ethylene / polyoxypropylene block copolymers, cationic surfactants such as alkylamine salts and quaternary ammonium salts, and silicone-based and fluorine-based surfactants.

Examples of silicone-based surfactants include polyether-modified polysiloxane compounds, specifically KF-351A, KF-352A, KF-642 and X-22-4272, Shin-Etsu Chemical, BYK307, BYK345, Includes BYK347 and BYK348, manufactured by Big Chemie (“BYK” is a registered trademark of the company), and TSF4452, manufactured by Momentive Performance Materials.

The fluorine-based surfactant means a substance in which a part or all of the hydrogen bonded to the carbon of the hydrophobic group of the ordinary surfactant is replaced with fluorine. Examples of fluorine-based surfactants include Megafac F, DIC (“Megafac” is a registered trademark of the company), Surflon, AGC Seichemical (“Surflon” is a registered trademark of the company), Fluorad FC, 3M. ("Fluorad" is a registered trademark of the company), Monflor, Imperial Chemical Industry, Zonyls, E.I. And FTERGENT, manufactured by Neos (“FTERGENT” is a registered trademark of the company).

The amount of the surfactant can be arbitrarily set as long as the effect of the present invention can be obtained. The amount of the surfactant can be, for example, 0.001% by mass or more and less than 1.0% by mass with respect to the total mass of the ink.

(Color material)
As a coloring material applicable to the active light-curable ink according to the present invention, a dye or a pigment can be applied, and the ink has good dispersibility with respect to the constituents of the ink and is excellent in weather resistance. , Pigments are more preferred.

<dye>
As the dye, an oil-soluble dye or the like can be applied. Examples of the oil-soluble dye include the following various dyes. Examples of magenta dyes include MS Magenta VP, MS Magenta HM-450, MS Magenta HSo-147 (all manufactured by Mitsui Toatsu Co., Ltd.), AIZENSOT Red-1, AIZEN SOT Red-2, AIZEN SOTRed-3, AIZEN SOT. Pink-1, SPIRON Red GEH SPECIAL (above, manufactured by Hodoya Chemical Co., Ltd.), RESOLIN Red FB 200%, MACROLEX Red Violet R, MACROLEX ROT5B (above, manufactured by Bayer Japan), KAYASET Red B, KAYASET 802 (above, manufactured by Nippon Kayakusha), PHLOXIN, ROSE
BENGAL, ACID Red (above, manufactured by Daiwa Kasei Corp.), HSR-31, DIARESIN Red K (above, manufactured by Mitsubishi Kasei Corp.), Oil Red (manufactured by BASF Japan) are included.

Examples of cyan dyes include MS Cyan HM-1238, MS Cyan HSo-16, Cyan HSo-144, MS Cyan VPG (above, manufactured by Mitsui Toatsu Co., Ltd.), AIZEN SOT Blue-4 (manufactured by Hodogaya Chemical Co., Ltd.), RESOLIN BR. Blue BGLN 200%, MACROLLEX Blue RR, CERES Blue GN, SIRIUS SUPRATURQ. Blue Z-BGL, SIRIUS SUPRA TURQ. Blue FB-LL 330% (above, manufactured by Bayer Japan), KAYASET Blue FR, KAYASET Blue N, KAYASET Blue 814, Turq. Blue GL-5 200, Light Blue BGL-5 200 (above, manufactured by Nippon Kayaku Co., Ltd.), DAIWA Blue 7000, Oleosol
Includes Fast Blue GL (above, manufactured by Daiwa Kasei Corp.), DIARESIN Blue P (manufactured by Mitsubishi Kasei Corp.), SUDAN Blue 670, NEOPEN Blue 808, ZAPON Blue 806 (above, manufactured by BASF Japan) and the like.

Examples of yellow dyes include MS Yellow HSm-41, Yellow KX-7, Yellow EX-27 (Mitsui Toatsu), AIZEN SOT Yellow-1, AIZEN SOT YellowW-3, AIZEN SOT Yellow-6 (above, Hodogaya). Chemical Co., Ltd.), MACROLLEX Yellow 6G, MACROLLEX FLUOR. Yellow 10GN (above, manufactured by Bayer Japan), KAYASET Yellow SF-G, KAYASET Yellow2G, KAYASET Yellow AG, KAYASET Yellow EG (above, manufactured by Nippon Kayaku Co., Ltd.), DAIWA Yellow 330H , HSY-68 (manufactured by Mitsubishi Kasei Corp.), SUDAN Yellow 146, NEOPEN Yellow 075 (manufactured by BASF Japan, Inc.) and the like are included.

Examples of black dyes include MS Black VPC (manufactured by Mitsui Toatsu Co., Ltd.), AIZEN SOT Black-1, AIZEN SOT Black-5 (above, manufactured by Hodoya Chemical Co., Ltd.), RESORIN Black GSN 200%, RESOLIN BlackBS (above, RESOLIN BlackBS). Bayer Japan), KAYASET Black A-N (Nippon Kasei), DAIWA Black MSC (Daiwa Kasei), HSB-202 (Mitsubishi Kasei), NEPTUNE Black X60, NEOPEN Black X58 (above, BASF) Made by Japan) etc. are included.

<Pigment>
It is preferable to apply a pigment as a coloring material to the active photocurable ink according to the present invention, and the pigment is not particularly limited, but for example, an organic pigment having the following number described in the Color Index (CI) or Ink pigments can be mentioned.

Examples of red or magenta pigments include Pigment Red 3, 5, 19, 22, 31, 38, 43, 48: 1, 48: 2, 48: 3, 48: 4, 48: 5, 49: 1, 53. 1, 57: 1, 57: 2, 58: 4, 63: 1, 81, 81: 1, 81: 2, 81: 3, 81: 4, 88, 104, 108, 112, 122, 123, 144 , 146, 149, 166, 168, 169, 170, 177, 178, 179, 184, 185, 208, 216, 226, 257, Pigment Violet 3, 19, 23, 29, 30, 37, 50, 88, Pigment Orange 13, 16, 20, 36 and the like are included. Examples of blue or cyan pigments include Pigment Blue 1, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17-1, 22, 27, 28, 29, 36. , 60 and the like are included. Examples of green pigments include Pigment Green 7, 26, 36, 50. Examples of yellow pigments include Pigment Yellow 1, 3, 12, 13, 14, 17, 34, 35, 37, 55, 74, 81, 83, 93, 94, 95, 97, 108, 109, 110, 137. 138, 139, 153, 154, 155, 157, 166, 167, 168, 180, 185, 193 and the like are included. Examples of black pigments include Pigment Black 7, 28, 26 and the like.

Examples of commercially available pigments include Chromofine Yellow 2080, 5900, 5930, AF-1300, 2700L, Chromofine Orange 3700L, 6730, Chromofine Scarlet 6750, Chromofine Magenta 6880, 6886, 6891N, 6790, 6878, Chromo. Fine Violet RE, Chromo Fine Red 6820, 6830, Chromo Fine Blue HS-3, 5187, 5108, 5197, 5085N, SR-5020, 5026, 5050, 4920, 4927, 4937, 4824, 4933GN-EP, 4940, 4973, 5205, 5208, 5214, 5221, 5000P, Chromo Fine Green 2GN, 2GO, 2G-550D, 5310, 5370, 6830, Chromo Fine Black A-1103, Seika Fast Yellow 10GH, A-3, 2035, 2054, 2200, 2270 , 2300, 2400 (B), 2500, 2600, ZAY-260, 2700 (B), 2770, Seika Fast Red 8040, C405 (F), CA120, LR-116, 1531B, 8060R, 1547, ZAW-262, 1537B , GY, 4R-4016, 3820, 3891, ZA-215, Seika Fast Carmine 6B1476T-7, 1843LT, 3840, 3870, Seika Fast Bordeaux 10B-430, Seika Light Rose R40, Seika Light Violet B800, 7805, Seika Fast Maroon. 460N, Seika Fast Orange 900, 2900, Seika Light Blue C718, A612, Cyanin Blue 4933M, 4933GN-EP, 4940, 4973 (manufactured by Dainichi Seika Kogyo);
KET Yellow 401, 402, 403, 404, 405, 406, 416, 424, KET Orange 501, KET Red 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 336, 337, 338, 346, KET Blue 101, 102, 103, 104, 105, 106, 111, 118, 124, KET Green 201 (manufactured by Dainippon Ink and Chemicals);
Colortex Yellow 301, 314, 315, 316, P-624, 314, U10GN, U3GN, UNN, UA-414, U263, Finecol Yellow T-13, T-05, Pigment Yellow 1705, Colortex Orange 202, Color 103 115, 116, D3B, P-625, 102, H-1024, 105C, UFN, UCN, UBN, U3BN, URN, UGN, UG276, U456, U457, 105C, USN, Colortex Maroon601, Colortex BrownB610N, Col. Red 122, Colortex
Blue516, 517, 518, 589, A818, P-908, 510, Colortex Green402, 403, Colortex Black 702, U905 (manufactured by Sanyo Dye);
Lionol Yellow1405G, Lionol Blue FG7330, FG7350, FG7400G, FG7405G, ES, ESP-S (manufactured by Toyo Ink), Toner Magenta E02, Permanent RubinF6B, Permanent RubinF6B, Toner Yellow HG, Perman
Novoperm P-HG, Hostaparm Pink E, Hostaparm Blue B2G (manufactured by Clariant);
Carbon Black # 2600, # 2400, # 2350, # 2200, # 1000, # 990, # 980, # 970, # 960, # 950, # 850, MCF88, # 750, # 650, MA600, MA7, MA8, MA11 , MA100, MA100R, MA77, # 52, # 50, # 47, # 45, # 45L, # 40, # 33, # 32, # 30, # 25, # 20, # 10, # 5, # 44, CF9 (Made by Mitsubishi Chemical) and so on.

Further, titanium oxide (particularly rutile-type titanium dioxide) can also be used as the white pigment.

The volume average particle size of the pigment is preferably 0.08 to 0.5 μm. The maximum particle size of the pigment is preferably 0.3 to 10 μm, more preferably 0.3 to 3 μm. By adjusting the particle size of the pigment, clogging of the nozzle of the inkjet recording head can be suppressed, and the storage stability of the ink, the transparency of the ink, and the curing sensitivity can be maintained.

In the present invention, the amount of the coloring material contained in the active photocurable ink is preferably in the range of 0.1 to 20% by mass, and in the range of 0.4 to 10% by mass with respect to the total mass of the ink. Is more preferable. This is because if the content of the pigment or dye is too small, the color of the obtained image is not sufficient, and if it is too large, the viscosity of the ink becomes high and the ejection property deteriorates.

<< Image recording method >>
First, as a method in which the image recording method of the present invention can be preferably used, an inkjet recording method, an electrophotographic method, a printing method using ink, or the like can be applied. The method will be described.

[Inkjet recording method]
Hereinafter, the inkjet recording method of the active light curing type inkjet method and the inkjet recording apparatus to be applied will be described with reference to the drawings. In the description of each figure, the numbers in parentheses at the end of the components represent the symbols in each figure.

The active ray curing type inkjet recording apparatus includes a line recording system (also referred to as a single pass recording system) and a serial recording system (also referred to as a scanning system). It may be selected according to the required image resolution and recording speed, but from the viewpoint of high-speed recording, the line recording method (single-pass recording method) is preferable.

(Line recording method)
The inkjet recording apparatus shown in FIGS. 4A and 4B is a recording apparatus for a line recording method. FIG. 4A is a side view of an example of the configuration of a main part of an inkjet recording device, and FIG. 4B is a top view thereof. As shown in FIGS. 4A and 4B, the inkjet recording apparatus (10) has a head carriage (16) accommodating a plurality of ink ejection recording heads (14) and a base material (12) on which a gloss adjusting layer is formed. The active light irradiation unit (18), which covers the entire width of the head carriage (16) and is arranged on the downstream side in the transport direction of the base material of the head carriage (16), and the temperature control unit (12) arranged on the lower surface of the base material (12). 19) and.

A plurality of ejection recording heads (14) of each color ink are fixedly arranged on the head carriage (16) so as to cover the entire width of the base material (12). Ink is supplied to the ink ejection recording head (14). For example, ink is supplied to the ink ejection recording head (14) directly or by the ink supply means (30) from an ink cartridge (31) or the like detachably attached to the inkjet recording device (10). You may have.

The base material (12) having the gloss adjusting layer whose glossiness is controlled is conveyed under the head carriage (16) fixed thereto to form the image recording layer.

A plurality of ink ejection recording heads (14) are arranged in the transport direction of the base material (12) for each color. The number of ink ejection recording heads (14) arranged in the transport direction of the substrate (12) is set by the nozzle density of the ink ejection recording head (14) and the resolution of the printed image. For example, when an image having a resolution of 1440 dpi is formed by using an ink ejection recording head (14) having a droplet amount of 2 pL and a nozzle density of 360 dpi, four ink ejections are performed with respect to the transport direction of the substrate (12). The recording heads (14) may be displaced and arranged. Further, when an image having a resolution of 720 × 720 dpi is formed by using an ink ejection recording head (14) having a droplet amount of 6 pl and a nozzle density of 360 dpi, the two ink ejection recording heads (14) are arranged in a staggered manner. do it. dpi represents the number of ink droplets (dots) per inch. One inch is 2.54 cm.

The active light irradiation unit (18) covers the entire width of the base material (12) and is arranged on the downstream side of the head carriage (16) in the transport direction of the base material (12). The active light irradiation unit (18) irradiates the droplets ejected by the ink ejection recording head (14) and landed on the gloss adjusting layer of the base material (12) with the active rays to cure the droplets.

On the downstream side of the head carriage (16), an active light irradiation part such as a metal halide lamp or an LED lamp is arranged so as to cover the entire width of the base material (12), and after the ink has landed on the base material (12). The metal is quickly irradiated with ultraviolet rays by a ride lamp or the like, and the image is completely fixed.

When the active light is ultraviolet light, examples of the active light irradiation unit (18, ultraviolet irradiation means) include a fluorescent tube (for example, a low-pressure mercury lamp, a germicidal lamp, etc.), a cold cathode tube, an ultraviolet laser, and up to several hundred Pa to 1 MPa. Low pressure, medium pressure, high pressure mercury lamps, metal halide lamps, LEDs and the like having the operating pressure of are included. From the viewpoint of curability, an ultraviolet irradiation means for irradiating ultraviolet rays having an illuminance of 100 mW / cm ² or more, specifically, a high-pressure mercury lamp, a metal halide lamp, an LED, or the like is preferable, and an LED is more preferable because it consumes less power. preferable. Specifically, a water-cooled LED manufactured by Phoseon Technology (wavelength: 395 nm) can be used.

When the active light is an electron beam, examples of the active light irradiation unit (18, electron beam irradiation means) include electron beam irradiation means such as a scanning method, a curtain beam method, and a broad beam method. From the viewpoint, the curtain beam type electron beam irradiation means is preferable. Examples of the electron beam irradiation means include "Curetron EBC-20-20-30" manufactured by Nissin High Voltage Co., Ltd., "Min-EB" manufactured by AIT Co., Ltd., and the like.

The temperature control unit (19) is arranged on the lower surface of the base material (12), and maintains the base material (12) at a predetermined temperature. By adjusting the temperature of the base material (12), the glossiness of the formed gloss adjusting layer and the image recording layer can be appropriately controlled. For example, various heaters and the like can be applied to the temperature control unit (19).

Hereinafter, an image recording method using a line recording type inkjet recording apparatus (10) will be described. The base material (12) is conveyed between the head carriage (16) of the inkjet recording device (10) and the temperature control unit (19). On the other hand, the base material (12) is adjusted to a predetermined temperature by the temperature control unit (19). Next, high-temperature ink is ejected from the ink ejection recording head (14) of the head carriage (16) and adhered (landed) on the gloss adjusting layer provided on the base material (12). Then, the active light irradiation unit (18) irradiates the ink droplets adhering on the base material (12) with the active light to cure the ink droplets.

When the ink is ejected from the ink ejection recording head (14), the temperature of the ink in the ink ejection recording head (14) is such that the ink contains a gelling agent in order to improve the ink ejection property. In some cases, it is preferable to set the temperature to be 10 to 30 ° C. higher than the gelation temperature of the ink. When the ink temperature in the ink ejection recording head (14) is less than (gelling temperature +10) ° C., the ink gels in the ink ejection recording head (14) or on the nozzle surface, and the ink ejection property Is easy to decrease. On the other hand, if the temperature of the ink in the ink ejection recording head (14) exceeds (gelation temperature +30) ° C., the ink becomes too high and the ink component may deteriorate.

The amount of ink droplets per drop ejected from each nozzle of the ink ejection recording head (14) depends on the resolution of the image, but is within the range of 1 to 10 pL in order to form a high-resolution image. It is preferably in the range of 0.5 to 4.0 pL, and more preferably in the range of 0.5 to 4.0 pL. In particular, in the present invention, it is preferable to eject and form an image with small droplets having an ink droplet amount in the range of 0.5 to 2.5 pL in order to form a high-definition image.

Irradiation with active light is performed within 10 seconds, preferably 0.001 to 5.0 seconds, after the ink droplets adhere to the substrate in order to suppress the coalescence of adjacent ink droplets. Within the range, more preferably within the range of 0.01 to 2.0 seconds. It is preferable to irradiate the active light beam collectively after ejecting ink from all the ink ejection recording heads (14) accommodated in the head carriage (16).

When the active ray is an electron beam, the acceleration voltage of the electron beam irradiation is preferably in the range of 30 to 250 kV, and more preferably in the range of 30 to 100 kV in order to perform sufficient curing. .. When the acceleration voltage is in the range of 100 to 250 kV, the electron beam irradiation amount is preferably in the range of 30 to 100 kGy, and more preferably in the range of 30 to 60 kGy.

The total ink film thickness after curing is preferably in the range of 2 to 25 μm. The "total ink film thickness" is the maximum value of the ink film thickness drawn on the substrate.

(Serial recording method (scan method))
FIG. 5 is a diagram showing an example of the configuration of a main part of a serial recording type inkjet recording apparatus (20). As shown in FIG. 5, the serial recording method is opposed to the line recording method described above in which the head carriage (16) in which the inkjet recording device (20) is fixedly arranged so as to cover the entire width of the base material is arranged. Then, as shown in FIG. 5, a head carriage (26) having a width narrower than the width of the base material and accommodating a plurality of ink ejection recording heads (24) and a head carriage (26) as the base material ( A guide portion (27) for moving in the width direction of 12) is provided, and the other configurations of the ink ejection recording head, the active light irradiation portion (18), and the like are described with reference to FIGS. 4A and 4B. It can have the same configuration as the line recording type inkjet recording device.

In the serial recording type inkjet recording apparatus (20), the ink contained in the head carriage (26) is stored in the head carriage (26) while the head carriage (26) moves toward the width of the base material (12) along the guide portion (27). Ink is ejected onto the gloss adjusting layer from the ejection recording head (24). The head carriage (26) has active light irradiation portions (28) at both ends and irradiates the active light. Except for these operations, an image is recorded in substantially the same manner as the above-mentioned line recording type inkjet recording apparatus (10).

[Electrograph recording method]
Details of the image recording method using the electrophotographic method will be omitted, but for example, Japanese Patent Application Laid-Open No. 2012-053099, Japanese Patent Application Laid-Open No. 2012-242578, Japanese Patent Application Laid-Open No. 2013-203818, Japanese Patent Application Laid-Open No. 2014-188950, and Japanese Patent Publication No. Toner configurations and electrophotographic records described in JP-A-2014-203056, JP-A-2016-188950, JP-A-2017-015810, JP-A-2017-161712, JP-A-2017-181743, etc. It can be applied by referring to the device and the like.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto. Although the display of "parts" or "%" is used in the examples, it represents "parts by mass" or "% by mass" unless otherwise specified. Unless otherwise specified, each operation was performed at room temperature (25 ° C.).

<< Preparation of coating liquid for forming gloss adjustment layer >>
[Preparation of coating liquid A-1 for forming a gloss adjusting layer]
As the resin dispersion, Byron 8210 (polyester-urethane resin manufactured by Toyobo Co., Ltd.) was used as the coating liquid A-1 for forming the gloss adjusting layer.

[Preparation of coating liquid A-2 for forming a gloss adjusting layer]
As the resin dispersion, Arrow Base SB-1230N (manufactured by Unitika Ltd., water-based chlorinated polyolefin) was used as the coating liquid A-2 for forming the gloss adjusting layer.

[Preparation of coating liquid A-3 for forming a gloss adjusting layer]
Each of the following additives was sequentially added to a stainless beaker and mixed to prepare a coating liquid A-3 for forming a gloss adjusting layer.

Organic fine particles: Chemisnow MX-150 (manufactured by Soken Chemical Co., Ltd., average particle size of acrylic fine particles: 1.5 μm) 10 parts by mass Water 80 parts by mass Isopropanol (IPA) 10 parts by mass.

[Preparation of coating liquid A-4 for forming a gloss adjusting layer]
A coating liquid A-4 for forming a gloss adjusting layer having the following constitution was prepared.

Inorganic fine particles: KE-P100 (manufactured by Nippon Catalyst Co., Ltd., Seahoster KE-P100, silica fine particles, average particle size: 1.0 μm) 10 parts by mass Isopropanol (IPA) 10 parts by mass Resin dispersion 1: SB-1230N (manufactured by Unitika) , Arrow base SB-1230N, aqueous chlorinated polyolefin) 80 parts by mass As a preparation procedure, put isopropanol in a stainless beaker, add inorganic fine particles (KE-P100) little by little while stirring at 300 rpm, and then add the whole amount. , Stirred at room temperature for 5 minutes.

Next, the resin dispersion 1 was added to and mixed with the prepared inorganic fine particles / isopropanol liquid to prepare a coating liquid A-4 for forming a gloss adjusting layer.
[Preparation of coating liquids A-5 to A-25 for forming a gloss adjusting layer]
In the preparation of the coating liquid A-4 for forming the gloss adjusting layer, the types and addition amounts of the resin dispersion 1, the resin dispersion 2 (acrylic), the organic fine particles 1, the inorganic fine particles, and the organic fine particles 2 (acrylic) are used. Preparations of coating liquids A-5 to A-25 for forming a gloss adjusting layer were prepared in the same manner except that the configurations shown in Tables I and II were changed.

The details of each additive listed above in Tables I and II by abbreviation are as follows.

(Resin dispersion 1)
Byron 8210: Toyobo Co., Ltd., polyester-urethane resin SB-1230N: Unitika Ltd., arrow base SB-1230N, water-based chlorinated polyolefin (resin dispersion 2 (acrylic))
Vinibran 278: PVC / acrylic copolymer resin manufactured by Nissin Chemical Industry Co., Ltd. MFR1924: Acrylic resin manufactured by Michelman (organic fine particles 1)
TR-2: Toray Industries, Inc., nylon fine particles, average particle size: 20 μm
SX-500H: Soken Chemical Co., Ltd., styrene fine particles, average particle size: 5 μm
KSR-3A: Soken Chemical Co., Ltd., styrene fine particles, average particle size: 3 μm
(Inorganic fine particles)
KE-P150: Nippon Shokubai Co., Ltd., Seahoster KE-P150, silica fine particles, average particle size: 1.5 μm
KE-P100: Nippon Shokubai Co., Ltd., Seahoster KE-P100, silica fine particles, average particle size: 1.0 μm
(Organic fine particles 2 (acrylic))
MR-7GC: Soken Chemical Co., Ltd., Chemisnow MR-7GC, acrylic fine particles, average particle size: 6 μm
MX-300: Soken Chemical Co., Ltd., Chemisnow MX-300, acrylic fine particles, average particle size: 3 μm
MX-150: manufactured by Soken Chemical Co., Ltd., Chemisnow MX-150, acrylic fine particles, average particle size: 1.5 μm.

<< Preparation of ink for forming image recording layer >>
Inks B-1 to B-5, which are active light curable inks, were prepared according to the following method.

[Preparation of ink B-1]
Each compound was mixed with the composition shown below, and the mixed solution was heated and stirred at 50 ° C. to prepare an ink. Then, the ink B-1, which is an active light curable ink, was prepared by filtering with a Teflon (registered trademark) 3 μm membrane filter manufactured by ADVANTEC.

<Color material>
Pigment dispersion a (see below) 12.5 parts by mass <Photopolymerizable compound 1>
APG-200 (NK Ester APG-200, manufactured by Shin Nakamura Chemical Industry Co., Ltd., tripropylene glycol diacrylate) 20.2 parts by mass SR355 (manufactured by Sartomer, trimethylolpropane tetraacrylate)
13.0 parts by mass A-9550 (NK ester A-9550, manufactured by Shin-Nakamura Chemical Co., Ltd., dipentaerythritol polyacrylate) 13.0 parts by mass ETERCURE6234 (Changxing Chemicals, epoxy acrylate oligomer)
5.0 parts by mass <Photopolymerizable compound 2: LogP4.0 to 7.0>
Miramer M360 (Miwon, trimethylolpropane 3PO modified triacrylate, molecular weight: 471, ClogP value: 4.90) 15.0 parts by mass Miramer M166 (Miwon, nonylphenol 8EO modified acrylate, molecular weight: 626, ClogP value: 6.42) 10.0 parts by mass <Surfactant>
BYK-307 (manufactured by Big Chemy Japan, polyether-modified polydimethylsiloxane) 0.1 part by mass <photoinitiator>
Irgacure 819 (BASF, bis (2,4,6-trimethylbenzoyl) -phenylphosphinoxide) 4.0 parts by mass Irgacure 369 (BASF, 2-benzyl-2-dimethylamino-1- (4-) Morphorinophenyl) -butanone-1) 3.0 parts by mass DETX (Labson, 2,4-diethylthioxanthone) 2.0 parts by mass <Sensitizer>
Speed Cure EHA (Made by Lambson, tertiary amine compound) 2.0 parts by mass <Polymerization inhibitor>
UV-10 (BASF, Irgas Tab UV-10)
<Preparation of pigment dispersion liquid a>
The following two compounds were placed in a stainless steel beaker and heated and stirred for 1 hour while heating on a hot plate at 65 ° C. to prepare a mixture.

EFKA4130 (manufactured by BASF) 9.0 parts by mass APG-100 (dipropylene glycol diacrylate, molecular weight 242 manufactured by Shin-Nakamura Chemical Co., Ltd.) 71 parts by mass The mixed solution was cooled to room temperature, and the following pigments were further added. This solution was placed in a glass bottle together with 200 g of zirconia beads having a diameter of 0.5 mm, sealed, and dispersed in a paint shaker for 5 hours. Then, the zirconia beads were removed to obtain a pigment dispersion liquid a.

Pigment Black 7 (manufactured by Mitsubishi Chemical Corporation, MA7) 20 parts by mass [Preparation of inks B-2 to B-5]
Inks B-2 to B-5 were prepared in the same manner as in the preparation of the ink B-1, except that the type and amount of each additive were changed to the configurations shown in Table III. In the preparation of B-2 to B-5, the heating temperature of the mixed solution was 85 ° C.

The details of each additive listed above in Table III by abbreviation are as follows.

<Photopolymerizable compound 1>
APG-200: NK Ester APG-200, manufactured by Shin-Nakamura Chemical Industry Co., Ltd., Tripropylene glycol diacrylate STA: manufactured by Osaka Organic Co., Ltd., Octadecyl acrylate A-TMM-3L: NK ester manufactured by Shin-Nakamura Chemical Co., Ltd. , Tetramethylol Methantriacrylate SR355: Sartomer, Ditrimethylol Propanetetraacrylate G3414: GENOMER3414, RAHN, Polyester Acrylate SR230: Sartomer, Diethylene Glycol Diacrylate A-9550: NK Ester A-9550, Shin-Nakamura Chemical Co., Ltd. ETERCURE 6234: Changxing Chemical, epoxy acrylate oligomer A-9300: NK ester A-9300, manufactured by Shin-Nakamura Chemical Co., Ltd., isocyanurate triacrylate.

<Photopolymerizable compound 2: LogP 4.0-7.0>
Miramer M360: Mion, trimethylolpropane 3PO modified triacrylate, molecular weight: 471, ClogP value: 4.90
Miramer M166: Made by Miwon, nonylphenol 8EO modified acrylate, molecular weight: 626, ClogP value: 6.42
A-DCP: NK ester A-DCP, manufactured by Shin-Nakamura Chemical Co., Ltd., tricyclodecanedimethanol diacrylate, molecular weight: 304, ClogP value: 4.69.

<Gelling agent>
WEP-2: Nissan Elector WEP-2, manufactured by NOF CORPORATION, ester wax, melting point 60 ° C.
Kao Wax T1: Kao Corporation, Distearyl Ketone Unistar M-9676: NOF Corporation, Stearyl Stearate WEP-4: Nissan Electol WEP-4, NOF Corporation, Ester Wax, Melt melting point 70 ° C.
Sriade S: Stearoamide ethyl stearate manufactured by Nihon Kasei.

<Surfactant>
BYK-307: Polyether-modified polydimethylsiloxane manufactured by Big Chemie Japan.

<Light initiator>
Irgacure 819: BASF, Bis (2,4,6-trimethylbenzoyl) -Phenylphosphinoxide Irgacure 369: BASF, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone- 1
DETX: 2,4-diethylthioxanthone manufactured by Rambson.

<Sensitizer>
Speed Cure EHA: Rambson, tertiary amine compound <polymerization inhibitor>
UV-10: Ilgas tab UV-10 manufactured by BASF.

《Image recording》
[Preliminary measurement of 60-degree mirror gloss of inks B-1 to B-5]
For the inks B-1 to B-5 prepared above, a transparent polyethylene terephthalate film having a thickness of 50 μm (hereinafter abbreviated as PET) is used as a base material, and the following inkjet recording method (scan method) is used. A sample for measuring the degree mirror gloss was prepared.

(Inkjet recording device)
Each black ink was loaded into an inkjet recording apparatus having an inkjet recording head equipped with a piezo-type inkjet nozzle having the configuration shown in FIG. 4A. From this device, each ink was ejected onto a PET film to create a solid black image.

The ink supply system consisted of an ink tank, an ink flow path, a sub ink tank immediately before the inkjet recording head, a pipe with a filter, and a piezo head. In the inkjet recording apparatus, four rows of piezo heads having a resolution of 360 dpi were arranged in the transport direction, and the PET film was heated at a predetermined temperature to obtain a recording resolution of 1440 × 1440 dpi.

The heating temperature of the PET film is 25 ° C. for the inks (B-1 and B-2) that do not contain the gelling agent, and 40 to 55 ° C. for the inks (B-3 to B-5) that contain the gelling agent. did.

The ink was heated from the ink tank to the head portion to a gelling temperature of Tgel + 30 ° C. Further, a voltage was applied to the piezo head so that the amount of each droplet was 3 pL, and a monochromatic black solid image was formed.

After the image was formed, the ink was cured by irradiating light having a wavelength of 395 nm from a water-cooled LED lamp manufactured by Heraeus. The distance from the surface of the LED lamp to the surface of the recording medium was set to 50 mm. At this time, the maximum illuminance on the surface of the recording medium was 3.5 W / cm ² , and the transport speed of the recording medium was 60 m / min. The amount of irradiated light was 400 mJ / cm ² .

(Measurement of 60 degree mirror gloss of black solid image)
The black solid image created above was measured using a variable angle gloss meter PG-1M and VGS-10001DP (manufactured by Nippon Denshoku Kogyo Co., Ltd.) in accordance with the measuring method specified in JIS Z 8741. The 60-degree mirror glossiness of the black solid image formed by each ink is shown below. The temperature in parentheses indicates the PET film temperature at the time of image formation.

Ink B-1: Glossiness = 81 (Image formation temperature: 25 ° C)
Ink B-2: Glossiness = 15 (Image formation temperature: 25 ° C)
Ink B-3: Glossiness = 52 (Image formation temperature: 55 ° C)
Ink B-4: Glossiness = 36 (Image formation temperature: 40 ° C)
Ink B-5: Glossiness = 21 (Image formation temperature: 25 ° C.).

[Preparation of image recording material]
Based on the information on the 60-degree mirror surface gloss of the inks B-1 to B-5 measured above according to the following method, image recording is performed in combination with the gloss adjustment layer having each 60-degree mirror surface gloss shown in Table IV. Materials 4-33 were formed. The image recording materials 1 to 3 shown in Table IV are comparative examples in which the gloss adjustment layer is not provided.

The details of the base material used for forming each of the following images are as follows.

(Base material)
NewDV: Recycled paper manufactured by Hokuetsu Kishu Sales Co., Ltd. (glossiness = 7)
PET: Transparent polyethylene terephthalate film with a thickness of 50 μm (glossiness: 95)
PVC: PSL-685, manufactured by Kaneka Corporation, made by applying paste PVC to a film thickness of 100 μm and drying it (glossiness: 20).
OKTC: OK Top Coat Plus, manufactured by Oji Paper Co., Ltd. (glossiness = 40)
PP: Corona-treated biaxially stretched polypropylene film OPP, manufactured by Okamoto.

(Preparation of image recording material 1)
Ink B-1 (glossiness = 81) was used as a base material on NewDV, and a black image (image recording layer 1) was produced as an image recording material 1 using the following scanning type inkjet recording apparatus.

<Formation of image recording layer 1 using a serial recording type inkjet recording device>
The inkjet recording apparatus of the serial recording method (also referred to as a scanning method) shown in FIG. 5 was used.

The ink supply system consisted of an ink tank, a supply pipe, an anterior chamber ink tank immediately before the head, a pipe with a filter, and a piezo head, and the front chamber tank to the head portion was insulated and heated at 50 ° C. The piezo head drives the ink B-1 to eject 2 to 15 pL multi-size dots at a resolution of 720 x 720 dpi (dpi stands for the number of dots per 2.54 cm), and the ink B-1 is imaged in FIG. As shown in the forming layer, the images were formed in a separated state so that the printing rate was 50%. The scanning speed of the carriage was 750 mm / s. After landing, the image was formed by irradiating the active light beam instantaneously (less than 1 second after landing) by the irradiation means provided on both sides of the carriage. As the irradiation means, a high-pressure mercury lamp VZero085 (manufactured by INTERTION TECHNOLOGY) is used, and the ink is cured by irradiating ultraviolet rays with an energy density of 140 W / cm and an illuminance of 20 mJ / cm ² (integrated light amount) to cure the image recording layer 1. It was formed and the image recording material 1 was produced.

(Preparation of image recording material 2)
The image recording material 2 formed a toner image (image recording layer 2, glossiness = 23) on PET as a base material by using an electrophotographic method.

The toner used was prepared by the following method.

60 g of Nuclel 699 resin (ethylene methacrylic acid copolymer by DuPont), 240 g of AC5120 resin (ethylene acrylic acid copolymer by AlliedSignal), and 1800 g of Isopar-L (Exxon). Was preheated in a heating bath set at 150 ° C. The Ross compound planetary mixer was then filled. These components were mixed at speed control setting 3 for about 1.5 hours to obtain a paste-like substance.

Next, 971.75 g of the paste-like substance was added to 55.66 g of the Hellogen Blue pigment 7080 (BASF), 4.14 g of the Hellogen Green pigment (BASF), 11.5 g of aluminum stearate (Riedel de Haen). And 1257 g of Isopearl L, packed in a 1S abrasion machine (Union Process Co., Ltd.) containing a chromium steel polishing medium, pulverized at 58 ° C. for about 1.5 hours, then pulverized at 45 ° C. for 10.5 hours, and toner. Was prepared. A charge control agent was added to the toner in an amount of 35 mg per 1 g of the toner solid.

Next, using the liquid toner printing system shown in FIG. 2 of Japanese Patent Laid-Open No. 2003-520997, the toner is printed on PET on PET under the condition that the printing rate is 50%, as shown in the image forming layer of FIG. Then, the image recording material 2 on which the image recording layer 2 was formed was produced.

(Preparation of image recording material 3)
An image recording layer 3 is formed on PET as a base material by using ink B-4 (glossiness = 36) to form a black image using an inkjet recording device of the following line recording method (thimble pass method), and the image recording material. 3 was produced.

<Formation of image recording layer 3 by line recording method>
The line recording type inkjet recording apparatus shown in FIG. 4A was used.

Ink B-4 was loaded into an inkjet recording apparatus having an inkjet recording head equipped with a piezo-type inkjet nozzle having the configuration shown in FIG. 4A. From this device, ink B-4 is printed on the PET film with the images separated so that the printing rate is 50%, as shown in the image forming layer of FIG. 1, and the image recording layer 3 is printed. Formed.

The ink supply system consisted of an ink tank, an ink flow path, a sub ink tank immediately before the inkjet recording head, a pipe with a filter, and a piezo head. In the inkjet recording apparatus, four rows of piezo heads having a resolution of 360 dpi were arranged in the transport direction, and the PET film was heated at a temperature of 40 ° C. to achieve a recording resolution of 1440 × 1440 dpi.

The ink was heated from the ink tank to the head portion to a gelling temperature of Tgel + 30 ° C. Further, a voltage was applied to the piezo head so that the amount of ink droplets was 3 pL, and a monochromatic grid-like black image was formed.

After the image was formed, the ink was cured by irradiating light having a wavelength of 395 nm from a water-cooled LED lamp manufactured by Heraeus. The distance from the surface of the LED lamp to the surface of the recording medium was set to 50 mm. At this time, the maximum illuminance on the surface of the recording medium was 3.5 W / cm ² , and the transport speed of the recording medium was 60 m / min. The amount of irradiated light was 400 mJ / cm ² .

(Preparation of image recording material 4)
In the production of the image recording material 3, the image recording layer (glossiness = 36) formed by the ink B-4 is selected as the image recording layer, and the conditions specified in the present invention are based on the glossiness information of the image recording layer. A-3 is selected as the coating liquid for forming the gloss adjusting layer so as to satisfy the above conditions, a gloss adjusting layer having a glossiness of 60 is formed between the base material and the image recording layer, and the image having the configuration shown in FIG. 1 is formed. The image recording material 4 was produced in the same manner except that the recording material was used.

<Formation of gloss adjustment layer>
Using the prepared coating liquid A-3 for forming a gloss adjusting layer, printing was performed on PET as a base material using the line recording type inkjet recording device under the condition that the layer thickness after drying was 8 μm, and gloss was obtained. An adjustment layer (glossiness = 60) was formed. However, no irradiation with active light was performed.

(Preparation of image recording materials 5 to 33)
In the production of the image recording material 4, the type of the base material, the heating temperature of the base material at the time of forming each layer, the type of the coating liquid for forming the gloss adjusting layer and the film thickness of the gloss forming layer, and the type of the ink liquid for forming the image recording layer. And the image recording method, the image recording materials 5 to 33 were produced in the same manner except that the combination shown in Table IV was changed.

<< Measurement of 60-degree mirror gloss >>
For the 60-degree mirror gloss of the image recording layer, an ink liquid for forming each layer recording layer is formed on the PET film, and the formed image recording layer conforms to the measurement method specified in JIS Z 8741. Then, a 60-degree mirror surface gloss G1 of the image recording layer was measured using a variable-angle gloss meter PG-1M and VGS-10001DP (manufactured by Nippon Denshoku Kogyo Co., Ltd.).

Regarding the 60-degree mirror glossiness of the gloss adjustment layer, a sample in which each gloss adjustment layer is formed on a substrate is used in the image recording materials 4 to 33, and the measurement method specified in JIS Z 8741 is compliant. The 60-degree mirror glossiness G2 of the gloss adjustment layer was measured with a variable-angle gloss meter PG-1M and VGS-10001DP (manufactured by Nippon Denshoku Kogyo Co., Ltd.).

Next, the gloss difference ΔG (G2-G1) was determined. For the image recording materials 1 to 3 having no gloss adjustment layer, the reference values, the glossiness of the base material, and the difference in glossiness of the image recording layer are shown.

<< Evaluation of image recording materials >>
The following evaluations were performed on each of the image recording materials produced above.

[Evaluation of gloss]
The glossiness of the glossiness difference ΔG (G2-G1) obtained in the above measurement or the glossiness difference between the base material and the image recording layer was evaluated according to the following evaluation ranks.

⊚: Absolute value of glossiness difference is 10 or less ○: Absolute value of glossiness difference is 11 or more and less than 20 Δ: Absolute value of glossiness difference is 20 or more and less than 30 ×: The absolute value of the glossiness difference is 30 or more.

[Evaluation of adhesion]
On the surface of the image recording layer, 6 grid-like cuts are made vertically and horizontally at 1 mm intervals with a cutter to create 25 grid-shaped squares, and 3M cellophane tape is attached to the surface. The cellophane tape was peeled off in the vertical direction, and the number of squares of the image recording layer remaining without being peeled off was counted, and this was used as a measure of adhesion.

[Evaluation of wettability]
Visually observe the surface of the layer recording layer having an area of 10 nm × 10 cm for each of the prepared image recording materials, count the number of white spot failures caused by repellents, etc. that occur during formation, and evaluate the wettability according to the following criteria. gone.

5: No white blank failure occurs 4: The number of white blank failures is about 1 to 2 places, and there is no problem in practical use. 3: There are 3 to 4 white blank failures, but there is a practical problem. No level 2: There are white spot failures in 5 to 6 places, but the quality is practically acceptable. 1: White blank failures occur in 7 or more places, which is a practically problematic quality. The results obtained are shown in Table V.

As is clear from the results shown in Table V, the image recording material of the present invention having a gloss adjustment layer designed to have a desired gloss based on the gloss information of the image recording layer specified in the present invention. An image having excellent glossiness can be obtained, and an image having excellent adhesion and wettability can be obtained as compared with the comparative example having no gloss adjustment layer.

More preferably, the glossiness difference ΔG (G2-G1) between the glossiness G2 of the gloss adjustment layer and the glossiness G1 of the image recording layer is set in the range of −20 to +20, and further, the glossiness difference ΔG. By setting (G2-G1) in the range of -10 to +5, the difference in glossiness between the image forming portion (glossiness G1 of the image recording layer) and the non-image forming portion (glossiness G2 of the gloss adjusting layer). Is preferable in that the image can be reduced in size and an image with less discomfort can be formed.

The image recording method of the present invention is an inkjet recording method for forming an image using an inkjet ink containing a dye or a pigment, or applying and fixing a toner containing a coloring material on paper or a thin film by an electrophotographic process to form an image. It can be applied to the electrophotographic method, screen printing method and offset printing method to form a pattern etc. on various base materials using printing ink, and reduce the gloss difference between the image forming part and the non-image forming part. Moreover, it can be suitably used for forming an image having excellent adhesion and wettability.

1 Image recording material 2, 12 Base material 3 Gloss adjustment layer 4 Image recording layer 5 Fine particles 10 Line recording type inkjet recording device 14, 24 Ink ejection recording head 16, 26 Head carriage 18, 28 Activated light irradiation unit 19 Temperature control Part 20 Serial recording type inkjet recording device 27 Guide part 30 Ink supply means 31 Ink cartridge G1 Gloss of image recording layer G2 Gloss of gloss adjustment layer hd Thickness of gloss adjustment layer r Average particle size of fine particles

Claims (11)

An image recording method in which a gloss adjustment layer is provided on a base material and an image recording layer is formed on the gloss adjustment layer.
An image characterized in that the 60-degree mirror gloss G1 of the image recording layer is measured in advance, and the 60-degree mirror gloss G2 of the gloss adjusting layer is adjusted according to the obtained information of the 60-degree mirror gloss G1. Recording method. The glossiness difference ΔG (G2-G1) between the 60-degree mirror surface gloss G2 of the gloss adjustment layer and the 60-degree mirror surface gloss G1 of the image recording layer is within the range of −20 to +20. The image recording method according to claim 1. The glossiness difference ΔG (G2-G1) between the 60-degree mirror surface gloss G2 of the gloss adjustment layer and the 60-degree mirror surface gloss G1 of the image recording layer is within the range of −10 to +5. The image recording method according to claim 1 or 2. The gloss adjusting layer is formed by a wet coating method using a coating liquid for forming a gloss adjusting layer containing the following component (2) in the range of 0.1 to 20% by mass with respect to the following component (1). The image recording method according to any one of claims 1 to 3, wherein the image recording method is characterized.
Component (1): Resin dispersion using an aqueous solvent as a dispersion medium Component (2): Organic or inorganic fine particles having an average particle size in the range of 1.0 to 20 μm. The image recording method according to claim 4, wherein the wet coating method is an inkjet printing method. The image recording method according to any one of claims 1 to 5, wherein the image recording layer is formed of an active ray-curable inkjet ink. The image recording method according to any one of claims 1 to 6, wherein the image recording layer is formed of an active photocurable inkjet ink containing a gelling agent. The gelling agent contains any one of the compounds having a structure represented by the following general formula (G1) or (G2) in an amount of 0.1 to 5.0% by mass based on the total mass of the active photocurable inkjet ink. Contains within the range of
Moreover, the photopolymerizable compound is contained in the range of 10 to 40% by mass of the total mass of the active photocurable inkjet ink, the photopolymerizable compound has a molecular weight in the range of 280 to 1500, and the ClogP value is. The image recording method according to claim 7, wherein the acrylate compound is in the range of 4.0 to 7.0.
General formula (G1): R ₁ -CO-R ₂
General formula (G2): R ₃ -COO-R ₄
[In the formula, R ₁ to R ₄ each independently represent a linear or branched alkyl group having a carbon number in the range of 12 to 26. ] The average particle size r of the organic or inorganic fine particles contained in the gloss adjusting layer is set in the range of 1.5 to 7.0 μm, and the film thickness hd after drying is set in the range of 1.0 to 3.0 μm.
Claims 4 to 8 are characterized in that the film thickness hd after drying of the gloss adjusting layer and the average particle size r of the organic or inorganic fine particles satisfy the conditions defined by the following formula (1). The image recording method according to any one of the above.
Equation (1)
Film thickness after drying of the gloss adjusting layer hd <average particle size of organic or inorganic fine particles r The image recording method according to any one of claims 4 to 9, wherein the resin dispersion contained in the gloss adjusting layer contains a resin containing an acrylic component. The image recording method according to any one of claims 4 to 10, wherein the organic fine particles contained in the gloss adjusting layer are acrylic fine particles.

Images