WO2018105416A1 - Recording-liquid set, ink-jet recording method, and ink/recording medium set - Google Patents

Abstract

The present invention addresses the problem of providing: a recording-liquid set capable of giving recorded images which have all of scratch resistance, unsusceptibility to cracking, and unsusceptibility to blurring; an ink-jet recording method; and an ink/recording medium set. The problem is solved with: a recording-liquid set comprising an ink and a pretreatment liquid comprising a coagulant and a resin, the resin having a degree of swelling A of above 100% but not higher than 500%; an ink-jet recording method including using the recording-liquid set; and an ink/recording medium set which comprises the ink and a recording medium comprising a non-absorbing base and, formed on a surface thereof, a pretreatment layer comprising a coagulant and a resin, the resin having a degree of swelling A of above 100% but not higher than 500%.

Description

Recording liquid set, ink jet recording method and ink / recording medium set

The present invention relates to a recording liquid set, an ink jet recording method, and an ink / recording medium set. More specifically, the present invention relates to a recording liquid set, an ink jet recording method, and an ink / The present invention relates to a recording medium set.

In recent years, there has been a growing demand for smaller lots and water-based inks, for example, in the field of flexible packaging printing. Non-absorbable substrates that do not absorb ink, such as films, are used for flexible packaging.

In the inkjet recording method, printing is performed by ejecting small droplets of ink from a fine nozzle head, causing them to fly and adhering to a recording medium. According to this method, a high-resolution and high-quality image can be printed at a high speed with a relatively inexpensive apparatus.

Patent Document 1 discloses that an image is formed by an ink jet method using an ink containing a fixing resin after a pretreatment liquid containing a component for aggregating ink is applied on a non-absorbent substrate. .

On the other hand, Patent Document 2 discloses a method in which a pretreatment liquid contains a resin. Conventionally, as such a resin, a resin having a high swelling rate has been frequently used in order to ensure compatibility with a flocculant and wettability to ink.

JP2015-131404A Japanese Patent No. 5828784

However, in the technique of Patent Document 1, when an amount of a resin capable of imparting practically sufficient abrasion resistance to an image is blended with the ink, the emission stability and storage stability in the ink jet method may be lowered.

On the other hand, the technique disclosed in Patent Document 2 has a problem that it is difficult to achieve both the scratch resistance, crack prevention and bleeding prevention of recorded images. In particular, it has been found that this problem becomes significant when the pretreatment layer formed by the pretreatment liquid is a thin film.

Therefore, an object of the present invention is to provide a recording liquid set, an ink jet recording method, and an ink / recording medium set that can achieve both the scratch resistance, crack prevention and bleeding prevention of a recorded image.

Further, other problems of the present invention will become apparent from the following description.

The above problems are solved by the following inventions.

1.
A pretreatment liquid containing at least a flocculant and a resin;
A recording liquid set comprising water, a colorant, a water-soluble solvent and an ink containing at least a surfactant,
A recording liquid set in which a swelling ratio A represented by the following formula (1) of the resin contained in the pretreatment liquid is greater than 100% and 500% or less.
Swelling ratio A (%) = {(w2-w0) / (w1-w0)} × 100 (1)
[In the formula (1), w0 is the weight (g) of a 6 cm square non-absorbent substrate, and w1 is applied to the 6 cm square non-absorbent substrate so that the applied amount is 1.6 g / m ^2. The weight (g) of the dried test piece, and w2 is the weight (g) when the test piece is immersed in water for 10 minutes. ]
2.
The resin contained in the pretreatment liquid is
A resin having both a polar part and a non-polar part, or
2. The recording liquid set according to 1 above, which is a mixture of a resin having a polar site and a resin having a nonpolar site.
3.
The resin contained in the pretreatment liquid is
A urethane resin having a swelling ratio A of more than 100% and 500% or less,
An acrylic resin having a swelling ratio A of more than 100% and 500% or less,
A mixture of an olefin resin and a urethane resin, or
3. The recording liquid set according to 1 or 2, which is a mixture of an olefin resin and an acrylic resin.
4).
4. The recording liquid set according to 3, wherein the olefin resin has a melting point of 100 ° C. or less.
5).
Weight ratio of olefin resin and urethane resin in the mixture of olefin resin and urethane resin, or
The weight ratio of olefin resin to acrylic resin in the mixture of olefin resin and acrylic resin is
5. The recording liquid set according to 3 or 4 above, which is 1: 9 to 8: 2.
6).
6. The recording liquid set according to any one of 3 to 5, wherein the olefin resin is chlorinated polyolefin.
7).
An ink jet recording method using the recording liquid set according to any one of 1 to 6,
Applying the pretreatment liquid to a non-absorbent substrate and drying to form a pretreatment layer,
Next, an ink jet recording method for recording an image by applying the ink onto the pretreatment layer by an ink jet method.
8).
8. The ink jet recording method according to 7, wherein the film thickness of the pretreatment layer is 0.5 μm to 5 μm.
9.
9. The ink jet recording method according to 7 or 8, wherein an image is recorded by applying the ink onto the pretreatment layer by a one-pass method by the ink jet method.
10.
An ink containing at least water, a colorant, a water-soluble solvent and a surfactant;
An ink / recording medium set comprising a recording medium provided with a pretreatment layer containing at least a flocculant and a resin on the surface of the non-absorbent substrate,
An ink / recording medium set in which a swelling ratio A represented by the following formula (1) of the resin contained in the pretreatment layer is greater than 100% and 500% or less.
Swelling ratio A (%) = {(w2-w0) / (w1-w0)} × 100 (1)
[In the formula (1), w0 is the weight (g) of a 6 cm square non-absorbing recording medium, and w1 is applied to the 6 cm square non-absorbing recording medium so that the applied amount is 1.6 g / m ^2. The weight (g) of the dried test piece, and w2 is the weight (g) when the test piece is immersed in water for 10 minutes. ]
11.
11. The ink / recording medium set according to 10, wherein the pretreatment layer has a thickness of 0.5 μm to 5 μm.

According to the present invention, it is possible to provide a recording liquid set, an ink jet recording method, and an ink / recording medium set that can achieve both the scratch resistance, crack prevention and bleeding prevention of recorded images.

Hereinafter, embodiments for carrying out the present invention will be described in detail.

1. Recording liquid set The recording liquid set of the present invention comprises a pretreatment liquid and ink. Here, the pretreatment liquid includes at least a flocculant and a resin. The ink includes at least water, a colorant, a water-soluble solvent, and a surfactant.

The present invention is characterized in that the resin contained in the pretreatment liquid has a specific swelling rate. That is, the resin contained in the pretreatment liquid has a later-described swelling ratio A of more than 100% and 500% or less.

As a result, it is possible to obtain an effect that can achieve both the abrasion resistance, crack prevention and bleeding prevention of the recorded image. This effect is also exhibited when the pretreatment layer formed by the pretreatment liquid is a thin film. Therefore, good image formation can be realized with high versatility regardless of the film thickness of the pretreatment layer. For example, by forming the pretreatment layer formed on the non-absorbent substrate as a thin film, it is possible to form a good image while suitably maintaining the original texture of the non-absorbent substrate. Such versatility is difficult to obtain with the technique of Patent Document 2 described above.

1-1. Pretreatment liquid <Flocculant>
The flocculant contained in the pretreatment liquid is not particularly limited as long as it can agglomerate the colorant contained in the ink. Examples thereof include acids, cationic polymers, polyvalent metal salts, and metal chelating agents. .

Examples of the acid include formic acid, acetic acid, propionic acid, isobutyric acid, oxalic acid, fumaric acid, malic acid, citric acid, malonic acid, succinic acid, maleic acid, benzoic acid, 2-pyrrolidone-5-carboxylic acid, and lactic acid. Acrylic acid or derivatives thereof, methacrylic acid or derivatives thereof, sulfonic acid derivatives, phosphoric acid or derivatives thereof, and the like. The acid may be either an inorganic acid or an organic acid.

Further, an acidic polymer may be used as the acid. Examples of the acidic polymer include polyacrylic acid or a derivative thereof, polymethacrylic acid or a derivative thereof, polysulfonic acid or a derivative thereof, polyphosphoric acid or a derivative thereof, and the like.

The acid may be neutralized, unneutralized or partially neutralized.

Examples of the cationic polymer include polymers having a primary to quaternary amine. The cationic polymer may be neutralized, unneutralized or partially neutralized.

As the polyvalent metal salt, a metal salt having a valence of 2 or more can be used. The type of metal (cation) constituting the polyvalent metal salt is not particularly limited, and examples thereof include divalent to tetravalent metal ions. Examples of the divalent metal ion include Ca ²⁺ , Cu ²⁺ , Ni ²⁺ , Mg ²⁺ , Zn ²⁺ , Ba ^{2+ and the} like. Examples of the trivalent metal ion include Al ³⁺ , Fe ³⁺ , Cr ³⁺ , Y ^{3+ and the} like. Examples of tetravalent metal ions include Zr ⁴⁺ . The type of salt constituting the polyvalent metal salt is not particularly limited, and examples thereof include carbonates, sulfates, nitrates, hydrochlorides, organic acid salts, borates, and phosphates. Specific examples of the polyvalent metal salt include calcium acetate and calcium chloride.

As the metal chelating agent, a complex (chelate complex) composed of a metal ion and a ligand (multidentate ligand) can be used. As a metal ion, what was demonstrated about the polyvalent metal salt can be used, for example. The ligand may be any ligand having a plurality of coordination sites, such as ethylenediamine, ethylenediaminetetraacetic acid, 1,2-propylenediaminetetraacetic acid, 1-phenylethylenediaminetetraacetic acid, 3,3-dimethylbutane-1 , 2-diaminetetraacetic acid, 1,2,3-triaminopropanehexaacetic acid, trimethylenediaminetetraacetic acid, nitrilotriacetic acid, 1,2-cyclohexanediaminetetraacetic acid, diethylenetriaminepentaacetic acid, glycol ethylenediaminetetraacetic acid, triethylenetetramine Hexaacetic acid, triethylenetetramine, tetraethylenepentamine, propane-1,2-diamine, butane-1,2-diamine, 3,3-dimethylbutane-1,2-diamine, 1,2,3-triaminopropane , Trimethylenediamine, tetralin-2,3- Amine tetraacetic acid, decalin-2,3-tetraacetic acid, cyclohexane-1,2-diaminetetraacetic acid, cyclohexane-1,3-diaminetetraacetic acid, cyclohexane-1,4-diaminetetraacetic acid, oxalic acid, tyrone, acetylacetone, etc. Can be mentioned.

The flocculant preferably contains a polyvalent metal salt or a metal chelating agent. Thereby, the effect of this invention is exhibited more favorably. In particular, metal ions are multivalent in polyvalent metal salts or metal chelators. Therefore, even when the pretreatment layer formed by the pretreatment liquid is a thin film, a sufficient valence can be ensured and the colorant can be well aggregated.

The ink can contain one or more flocculants.

<Resin>
The resin contained in the pretreatment liquid has a swelling ratio A of more than 100% and 500% or less.

The swelling rate A is represented by the following formula (1).

Swelling ratio A (%) = {(w2-w0) / (w1-w0)} × 100 (1)
[In the formula (1), w0 is the weight (g) of a 6 cm square non-absorbent substrate, and w1 is applied to the 6 cm square non-absorbent substrate so that the applied amount is 1.6 g / m ^2. The weight (g) of the dried test piece, and w2 is the weight (g) when the test piece is immersed in water for 10 minutes. ]

The pretreatment liquid can contain one or more kinds of resins as long as the swelling ratio is satisfied. When a plurality of types of resins are used in combination as the resin for the pretreatment liquid, the composition of the resin applied and dried to the test piece when the swelling ratio A is measured is the same as that of the resin for the pretreatment liquid.

If a resin satisfying the above-described swelling rate is used, the rub resistance and crack prevention properties are universally exhibited regardless of the film thickness of the pretreatment layer. The reason for this is presumed that the swelling of the pretreatment layer by the ink is moderately suppressed. That is, even if the pretreatment layer is a thin film, all of the resin in the pretreatment layer is hardly swollen. Thereby, it is prevented that ink is immersed in the back side (base material side) of the pretreatment layer, and the abrasion resistance and the crack prevention property are exhibited.

Further, if a resin that satisfies the above-described swelling rate is used, the swelling of the pretreatment layer by the ink is not completely prevented, and the release of the flocculant accompanying the appropriate swelling of the pretreatment layer is ensured. Thereby, the bleeding prevention property is exhibited.

Examples of the resin that satisfies the above-described swelling rate include the following embodiments 1 to 3.

In aspect 1, the resin that satisfies the above-described swelling rate is a resin that has been moderately reduced in swelling rate by crosslinking a resin having a high swelling rate.

In the second aspect, the resin that satisfies the above-described swelling rate satisfies the hydrophilicity of the resin having a high swelling rate by appropriately reducing the hydrophilicity and appropriately reducing the swelling rate.

In aspect 3, the resin satisfying the swelling ratio described above is a resin having both a polar part and a nonpolar part, or a mixture of a resin having a polar part and a resin having a nonpolar part.

Among these resins according to aspects 1 to 3, the resin according to aspect 3 is particularly preferable from the viewpoint of satisfactorily exerting the effects of the present invention.

That is, in the method using the cross-linking of aspect 1, it may take time for the cross-linking reaction or aging. Moreover, since high water resistance is irreversibly imparted after crosslinking, the ink may be repelled, making it difficult to form a good image. For example, an image may be formed before all the crosslinking reactions are completed, but the process may be complicated, for example, it is necessary to control the progress of the crosslinking reaction. In addition, in the method of reacting the hydrophilic group of aspect 2, it may be difficult to react the hydrophilic group uniformly. Therefore, it may be difficult to make the swelling rate of the resin uniform.

On the other hand, in the method of aspect 3, the desired swelling ratio can be reliably and uniformly imparted to the resin. Thereby, the effect of abrasion resistance and crack prevention property is exhibited reliably. Furthermore, since a sufficient amount of the flocculant is encapsulated and released, the ink is suitably aggregated and the bleeding prevention property is further improved. As a result, higher image quality can be ensured.

The resin contained in the pretreatment liquid is preferably a urethane resin having a swelling ratio A of more than 100% and 500% or less, or an acrylic resin having a swelling ratio A of more than 100% and 500% or less. These urethane resins and acrylic resins may be obtained by synthesis or may be obtained as commercial products.

When synthesizing these urethane resins and acrylic resins, polymerization components (for example, monomers, oligomers or prepolymers) used for polymerization so that the swelling ratio A of the resulting resin is greater than 100% and not more than 500%. The type and composition can be selected as appropriate. At this time, for example, a polymerization component having polarity can contribute to an increase in swelling rate, and a polymerization component having no polarity can contribute to a decrease in swelling rate.

Examples of commercially available products of these urethane resins and acrylic resins include “Superflex 650” (urethane resin) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. and “New Coat WSM2006” (acrylic resin) manufactured by Shin-Nakamura Chemical Co., Ltd. .

Also, the resin contained in the pretreatment liquid is preferably a mixture of an olefin resin and a urethane resin, or a mixture of an olefin resin and an acrylic resin. Thereby, the abrasion resistance of the image is further improved.

The weight ratio of the olefin resin and the urethane resin in the mixture of the olefin resin and the urethane resin is preferably 1: 9 to 8: 2. The weight ratio of the olefin resin and the acrylic resin in the mixture of the olefin resin and the acrylic resin is preferably 1: 9 to 8: 2. Thereby, the abrasion resistance of the image is further improved in a state where the bleeding prevention property is satisfactorily maintained.

The olefin resin used in the mixture is not particularly limited, but for example, chlorinated polyolefin can be preferably used. By using the chlorinated polyolefin, the abrasion resistance of the image is further improved. The chlorinated polyolefin is commercially available, for example, as “Supercron E-415” manufactured by Nippon Paper Industries Co., Ltd.

Also, the olefin resin used in these mixtures preferably has a melting point of 100 ° C. or lower. Thereby, the film-forming temperature of the pre-processing layer formed with a pre-processing liquid can be set low, and the effect which can suppress suitably the deformation | transformation etc. of the non-absorbent base material which consists of a film etc., for example is acquired.

The resin contained in the pretreatment liquid may be, for example, cationic or nonionic.

Resin can be contained in the pretreatment liquid as, for example, resin fine particles. The volume average particle diameter of the resin fine particles can be, for example, 10 nm to 10 μm. The volume average particle size can be measured by a commercially available particle size measuring instrument using dynamic light scattering method, electrophoresis method, etc., but the measurement by dynamic light scattering method is simple and the particle size region. Can be measured accurately.

The resin content in the pretreatment liquid is not particularly limited, and can be, for example, 5 wt% to 40 wt%.

Further, in the pretreatment liquid, when the resin content is 100 parts by weight, the content of the above-mentioned flocculant can be 5 to 40 parts by weight. The ratio of the content of the resin and the flocculant can be maintained in the pretreatment layer formed by the pretreatment liquid.

<Solvent>
The pretreatment liquid can contain a flocculant and a resin dissolved or dispersed in a solvent. A solvent is not specifically limited, For example, it can be comprised by 1 type, or multiple types selected from water, an organic solvent, etc.

<Other ingredients>
In addition to the components described above, the pretreatment liquid can contain other components as long as the effects of the present invention are not impaired. Examples of other components include surfactants, crosslinking agents, antifungal agents, and bactericides.

1-2. Ink <Colorant>
Examples of the colorant contained in the ink include dyes and pigments, and pigments can be preferably used.

The pigment is not particularly limited, and any of a water dispersible pigment, a solvent dispersible pigment, and the like can be used. For example, an organic pigment such as an insoluble pigment or a lake pigment, or an inorganic pigment such as titanium oxide or carbon black can be used. it can. These pigments can be dispersed in the ink by using, for example, a dispersant described later.

The insoluble pigment is not particularly limited. , Diketopyrrolopyrrole and the like are preferable.

The organic pigment is not particularly limited, but the following can be preferably exemplified.

Examples of pigments used for yellow or orange include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 15: 3, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 128, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 138, C.I. I. And CI Pigment Yellow 155.

Examples of pigments used for magenta or red include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. Pigment red 202, C.I. I. Pigment red 222, C.I. I. Pigment violet 19 and the like.

Examples of pigments used for cyan or green include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.

Also, examples of pigments used for black and the like include C.I. I. Pigment black 1, C.I. I. Pigment black 6, C.I. I. Pigment black 7 and the like.

The average particle diameter of the dispersed state of the pigment in the ink can be, for example, 50 nm to 200 nm. The particle size of the pigment can be determined by a commercially available particle size measuring instrument using a dynamic light scattering method, an electrophoresis method, etc., but the measurement by the dynamic light scattering method is simple and the particle size region is Accurate measurement.

Colorants, particularly pigments, can be used by dispersing with a disperser together with necessary additives. As the disperser, for example, a ball mill, a sand mill, a line mill, a high-pressure homogenizer, or the like can be used.

The ink can contain one or more colorants. The content of the colorant in the ink is not particularly limited. For example, the inorganic pigment may be 7 wt% to 18 wt%, and the organic pigment may be 0.5 wt% to 7 wt%.

<Dispersant>
The ink can include a dispersant. The dispersant contributes to the dispersion of the colorant in the ink.

As the dispersant, for example, a polymer dispersant (also referred to as a dispersion resin) or the like can be used. As the dispersion resin, one having an acid value can be preferably used. Although an acid value is not specifically limited, For example, it can be set as 50 mgKOH / g or more and 250 mgKOH / g or less.

As the dispersant, for example, an acrylic dispersant can be used. As the acrylic dispersant, one or more selected from poly (meth) acrylic acid and (meth) acrylic acid copolymer can be used.

The acrylic dispersant contains (meth) acrylic acid as a monomer component. As an acrylic dispersant, a copolymer of (meth) acrylic acid (ie, poly (meth) acrylic acid) or a copolymer obtained by copolymerizing other monomer components such as styrene as needed (ie, (meth)) (Acrylic acid copolymer) can be used.

The ink can contain one or more dispersants. The content of the dispersant in the ink is not particularly limited, and can be appropriately set in consideration of the content of the colorant and the like.

<Water and water-soluble solvents>
The ink contains water and a water-soluble solvent. These function as solvents in the ink.

Examples of the water-soluble solvent include monohydric alcohols, glycols (dihydric alcohols), trihydric alcohols, glycol ethers, acetates, amines, amides, and the like.

Examples of monohydric alcohols include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, and tertiary butanol.

Examples of glycols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol having 5 or more ethylene oxide groups, propylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, and propylene oxide groups. Polypropylene glycol, butylene glycol, thiodiglycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,2-hexanediol 1,2-heptanediol, 3-methyl-2,4-pentanediol, and the like.

Examples of trihydric alcohols include glycerin and hexanetriol.

Examples of glycol ethers include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, Triethylene glycol monopropyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipro Lenglycol monoethyl ether, dipropylene glycol monopropyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, tetrapropylene glycol monomethyl ether, diethylene glycol diethyl ether, diethylene glycol Examples include dibutyl ether, triethylene glycol diethyl ether, triethylene glycol dibutyl ether, dipropylene glycol dibutyl ether, and tripropylene glycol dibutyl ether.

Examples of acetates include ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol diacetate and the like.

Examples of amines include ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenediamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, Examples include pentamethyldiethylenetriamine and tetramethylpropylenediamine.

Examples of amides include 2-pyrrolidinone, dimethylimidazolidinone, formamide, N, N-dimethylformamide, N, N-dimethylacetamide and the like.

The ink can contain one or more water-soluble solvents.

<Surfactant>
The surfactant contained in the ink contributes to the improvement of the emission stability in the ink jet method and the wettability upon landing.

The surfactant is not particularly limited, and examples thereof include a cationic surfactant, an anionic surfactant, an amphoteric surfactant, and a nonionic surfactant.

Examples of the cationic surfactant include aliphatic amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, and the like.

Examples of the anionic surfactant include fatty acid soap, N-acyl-N-methylglycine salt, N-acyl-N-methyl-β-alanine salt, N-acyl glutamate, acylated peptide, alkyl sulfonic acid Salt, alkylbenzene sulfonate, alkyl naphthalene sulfonate, dialkyl sulfosuccinate, alkyl sulfoacetate, α-olefin sulfonate, N-acylmethyl taurine, sulfated oil, higher alcohol sulfate, secondary Higher alcohol sulfate, alkyl ether sulfate, secondary higher alcohol ethoxysulfate, polyoxyethylene alkylphenyl ether sulfate, monoglyculate, fatty acid alkylolamide sulfate, alkyl ether phosphate ester, alkyl Examples include phosphate ester salts.

Examples of amphoteric surfactants include carboxybetaine type, sulfobetaine type, aminocarboxylate, and imidazolinium betaine.

Examples of the nonionic surfactant include polyoxyethylene secondary alcohol ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, polyoxyethylene polyoxypropylene alkyl ether, and polyoxyethylene. Glycerin fatty acid ester, polyoxyethylene castor oil, hydrogenated castor oil, polyoxyethylene sorbitol fatty acid ester, polyethylene glycol fatty acid ester, fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, fatty acid alkanol Amides, polyoxyethylene fatty acid amides, polyoxyethylene alkylamines, alkylamines Kisaido, acetylene glycol, acetylene alcohol, and the like.

From the viewpoint of reducing the surface tension, it is preferable that some of these surfactants are substituted with fluorine atoms or silicon atoms.

The ink can contain one or more surfactants. The content of the surfactant in the ink can be, for example, 0.1 wt% to 5.0 wt%.

<Other ingredients>
In addition to the components described above, the ink can contain other components as long as the effects of the present invention are not impaired.

<Ink physical properties>
The ink preferably has a surface tension of 45 mN / m or less. Thereby, the effect of this invention is exhibited more favorably. The surface tension is a value measured by Wilhelmi's plate method in an environment of 25 ° C. and 50% RH.

2. Inkjet recording method The inkjet recording method of the present invention uses the recording liquid set described above.

First, a pretreatment liquid is applied to a non-absorbent substrate and dried to form a pretreatment layer. Next, an ink is applied onto the pretreatment layer by an inkjet method to record an image.

<Non-absorbent substrate>
Examples of the non-absorbent substrate include a film, glass, tile, rubber and the like, and a film is particularly preferable.

Examples of the film include a plastic film. Examples of the plastic film include a polyester film containing polyethylene terephthalate and the like; a polyolefin film including polyethylene film and polypropylene film; a polyamide film including nylon and the like; a polystyrene film; a polyvinyl chloride film; a polycarbonate film; and a polyacrylonitrile film; And biodegradable films including lactic acid films. In addition, in order to impart gas barrier properties, moisture resistance, fragrance retention, etc., a film coated with polyvinylidene chloride on one side or both sides, or a film deposited with a metal oxide may be used.

The film may be an unstretched film or a stretched film.

Also, a film that has been subjected to antifogging processing may be used. In general, examples of the film subjected to the antifogging process include a film containing a surfactant.

The surface of the non-absorbent substrate may be surface-treated by corona discharge or ozone treatment.

<Application of pretreatment liquid>
The method for applying the pretreatment liquid to the non-absorbent substrate is not particularly limited, and examples thereof include a roller coating method, a curtain coating method, a spray coating method, and an ink jet method.

<Drying of pretreatment liquid>
The method for drying the pretreatment liquid applied to the non-absorbent substrate is not particularly limited, and natural drying, drying with warm air, drying with a heater, or the like can be used.

<Pretreatment layer>
By applying and drying the pretreatment liquid on the non-absorbent substrate, a pretreatment layer containing at least a flocculant and a resin is formed on the surface of the non-absorbent substrate. In the following description, a non-absorbent substrate provided with a pretreatment layer may be referred to as a recording medium.

The film thickness of the pretreatment layer is preferably 0.5 μm to 5 μm. When the film thickness of the pretreatment layer is 0.5 μm or more, a sufficient amount of the flocculant can be contained. Moreover, when the pretreatment layer is a thin film having a film thickness of 5 μm or less, the texture inherent to the non-absorbent substrate can be suitably maintained. In the case where the pretreatment layer is a thin film, it is particularly difficult to achieve both the abrasion resistance, crack prevention and bleeding prevention of the recorded image with the conventional technology. However, according to the present invention, these characteristics can be suitably achieved. . Such an effect is more effectively exhibited when the film thickness of the pretreatment layer is 0.5 μm to 2 μm.

The pretreatment layer preferably has a surface energy of 44 mN / m or more. Thereby, the effect of this invention is exhibited more favorably. The surface energy is a value in an environment of 25 ° C. and 50% RH.

The weight ratio of the resin and the flocculant in the pretreatment layer can be appropriately set. For example, when the resin content is 100 parts by weight, the content of the flocculant is 5 to 40 parts by weight. It can be a weight part. The amount of the flocculant in the pretreatment layer can be set as appropriate, and can be set to, for example, 0.03 g / m ² to 1.5 g / m ² .

<Inkjet method>
In the ink jet method, using a printer including an ink jet head loaded with the ink described above, ink is ejected as droplets from the nozzle of the ink jet head based on a digital signal, and this is landed on the above-described pretreatment layer to form an image. Can be recorded.

The inkjet head may be either an on-demand system or a continuous system. As an inkjet head droplet discharge method, an electro-mechanical conversion method (for example, a single cavity type, a double cavity type, a bender type, a piston type, a shear mode type, a sheared wall type, etc.), an electro-thermal conversion method ( For example, any system such as a thermal ink jet type or a bubble jet (registered trademark) type may be used.

In particular, an ink jet head (also referred to as a piezo ink jet head) using a piezoelectric element as the electro-mechanical conversion element used in the electro-mechanical conversion system is suitable.

Inkjet printers have two printing methods called a scanning method (also called a multi-pass method) and a single-pass method (also called a one-pass method).

For example, the scanning method is a method in which the head carriage is reciprocated in the horizontal direction (main scanning direction) with respect to the recording medium conveyance direction (sub-scanning direction), and the image is completed by a plurality of passes. Although it is slow, the number of heads used can be reduced.

On the other hand, the single pass method is a method in which, for example, a line head type ink jet head (head carriage) is fixed, and an image is completed on a transported recording medium by a single pass. Productivity is obtained.

The line head type inkjet head refers to an inkjet head having a length longer than the width of the printing range. As the line head type ink jet head, a single head having a width larger than the print range may be used, or a plurality of heads may be combined so as to be larger than the width of the print range. It is also preferable to arrange a plurality of heads side by side so that the nozzles are arranged in a staggered arrangement, thereby increasing the resolution of the heads as a whole.

In the inkjet method, for example, in order to prevent nozzle clogging due to ink drying, a maintenance operation for discharging ink from the nozzles can be executed. This operation can be executed in a state where the ink jet head is moved out of the region on the recording medium (that is, a state where ink is not applied to the recording medium). In the scanning method, the inkjet head can be easily moved out of the area on the recording medium by scanning. On the other hand, in the single pass method, since the inkjet head is usually fixed, it is relatively difficult to move out of the area on the recording medium. On the other hand, in the present invention, by including a resin in the pretreatment liquid, the fixing resin for the ink can be omitted (or the amount can be reduced), so that the burden of ink discharge can be reduced. Stable injection can be suitably achieved.

<Ink drying>
The method for drying the ink applied on the pretreatment layer is not particularly limited, and natural drying, drying with warm air, drying with a heater, or the like can be used.

The ink drying temperature may be set higher than the pretreatment liquid drying temperature. At this time, the heating for drying the ink may advance the film formation of the pretreatment layer.

3. Ink / Recording Medium Set The ink / recording medium set of the present invention includes ink and a recording medium. Here, the description about a recording liquid set is used about ink. For the recording medium, the description of the ink jet recording method is incorporated.

As mentioned above, although each invention of the recording liquid set, the ink jet recording method, and the ink / recording medium set has been described, the description of one invention is appropriately incorporated in other inventions.

Hereinafter, examples of the present invention will be described, but the present invention is not limited to the examples.

Example 1
1. Preparation of pretreatment solution “Superflex 650” (cationic carbonate urethane resin, solid content 26 wt%, melting point 203 ° C.) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. (An aqueous solution containing zirconyl chloride and aminocarboxylic acid) and ion-exchanged water (hereinafter simply referred to as water) as a solvent were mixed and stirred to obtain a pretreatment liquid. The amount of each component is adjusted so as to have the value shown in the pretreatment liquid composition in Table 1. In addition, in the pretreatment liquid composition shown in Table 1, the compounding amount (wt%) of the resin and the flocculant is a value in terms of solid content. The degree of swelling A of the contained resin is as shown in Table 1.

The degree of swelling A was determined as follows. First, a 6 cm square non-absorbent substrate was prepared, and its weight w0 (g) was measured. Next, a resin to be measured for the degree of swelling A is applied to the non-absorbent substrate so that the applied amount is 1.6 g / m ² (after drying), and dried at 70 ° C. on a hot plate. A test piece was obtained, and the weight w1 (g) of the test piece was measured. Subsequently, the weight w2 (g) when the said test piece was immersed in 25 degreeC (room temperature) water for 10 minutes was measured. By substituting these values of the weights w0 to w2 into the above formula (1), the degree of swelling A was determined.

2. Preparation of inks C.I. I. Pigment Blue 15: 3 (cyan pigment, abbreviated as PB15: 3), pigment dispersion resin (styrene-acrylic acid copolymer, polymerization average molecular weight: 14500, acid value: 75 mgKOH / g) as a dispersant, and water-soluble solvent Ethylene glycol, “Olfin E1010” (acetylene glycol surfactant) manufactured by Nissin Chemical Co., Ltd. as a surfactant, and water were mixed, stirred, and then filtered through a 10 μm membrane filter to obtain an ink. . In preparing the ink, a pigment dispersion containing a colorant, a dispersant and water was prepared in advance, and the remaining components were mixed with the pigment dispersion to obtain an ink. The amount of each component is adjusted so as to be the value shown in the ink composition of Table 1. In the ink composition shown in Table 1, the blending amount (wt%) of the colorant and the dispersant is a value in terms of solid content.

3. Image recording On a non-absorbent substrate (“FOS-BT” (polypropylene film) manufactured by Phutamura Chemical Co., Ltd.), the obtained pretreatment liquid was applied with a solid content of 1.6 g / m ² (film thickness after drying 1 Was applied using a bar coater # 5 so as to be equivalent to 6 μm, and then dried at 70 ° C. for 5 minutes to form a pretreatment layer. Table 1 shows the surface energy of the pretreatment layer.

Next, ink was ejected from the inkjet head and deposited on the pretreatment layer to record an image. The ink recording conditions were an image resolution of 720 × 720 dpi and an ink adhesion amount of 48 g / m ² (wetting amount).

Next, the recorded image was heated and dried at 80 ° C. to obtain a recorded image (hereinafter also referred to as an evaluation sample). It was confirmed that the obtained image was not sticky when touched with a finger.

4). Evaluation Method The obtained evaluation sample was evaluated by the following method.

(1) Abrasion resistance The state after rubbing the printed surface (image recording surface) 10 times using “Bem Cotton” (registered trademark) manufactured by Asahi Kasei Corporation is visually observed, and the abrasion resistance is evaluated according to the following evaluation criteria. did.
[Evaluation criteria]
AA: No stain on the bem cotton and no peeling of the image A: Some stain on the bem cotton but no peeling of the image B: No stain on the bem cotton but no peeling of the image C: Bemcotton is dirty and image peeling

(2) Crack prevention properties The presence or absence of cracks in the solid print portion of the image was visually observed, and the crack prevention properties were evaluated according to the following evaluation criteria.
[Evaluation criteria]
A: No cracks B: Some cracks are seen, but in practically acceptable range C: Cracks are clearly seen

(3) Bleeding prevention The presence or absence of bleeding in the contour of the image was visually observed, and the bleeding prevention was evaluated according to the following evaluation criteria.
[Evaluation criteria]
A: No bleeding C: Bleeding

The above evaluation results are shown in Table 1.

(Example 2)
In Example 1, instead of “Superflex 650”, a cationic urethane resin (solid content: 20 wt%) obtained by the following “<Synthesis of cationic aqueous urethane resin” was used as the resin for the pretreatment liquid. An evaluation sample was obtained in the same manner as in Example 1 except that calcium acetate monohydrate was used in place of “Ticks ZB-126” and the pretreatment liquid composition shown in Table 1 was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

<Synthesis of cationic aqueous urethane resin>
22.8 parts by weight of polycarbonate polyol (molecular weight 1000, Nipponran 981, Nippon Polyurethane Industry Co., Ltd.), 1.37 parts by weight of polyethylene glycol (molecular weight 600, Daiichi Kogyo Seiyaku Co., Ltd.), 57 parts by mass, 2.74 parts by weight of N-methyl-N, N-diethanolamine, 14.7 parts by weight of isophorone diisocyanate, and 21.1 parts by weight of methyl ethyl ketone (abbreviation: MEK) were put in a reaction vessel at 70 ° C. The reaction was carried out for 5 hours while maintaining at ˜75 ° C. to obtain a urethane prepolymer. 0.276 parts by weight of dimethyl sulfate was added to the obtained urethane prepolymer and reacted at 55 ° C. to 60 ° C. for 1 hour to obtain a cationic urethane polymer. Thereafter, 106 parts by weight of water was uniformly added and emulsified, and then MEK was recovered to obtain a cationic polyurethane resin.

(Example 3)
In Example 1, “New Coat WSM 2006” (acrylic polymer, solid content 46 wt%) manufactured by Shin-Nakamura Chemical Co., Ltd. was used in place of “Superflex 650” as the resin for the pretreatment liquid, and the pretreatment liquids shown in Table 1 were used. An evaluation sample was obtained in the same manner as in Example 1 except that the composition was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

Example 4
In Example 1, “New Coat SFK2000A” (acrylic polymer, solid content: 46 wt%) manufactured by Shin-Nakamura Chemical Co., Ltd. was used in place of “Superflex 650” as the resin for the pretreatment liquid, and “Orugatics ZB-126” was used. An evaluation sample was obtained in the same manner as in Example 1 except that calcium acetate monohydrate was used instead of and the pretreatment liquid composition shown in Table 1 was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

(Example 5)
In Example 1, instead of “Superflex 650” as a pretreatment liquid resin, “Superflex 620” (cationic ester urethane resin, solid content 30 wt%, melting point 186 ° C.) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. and Nippon Paper Industries Co., Ltd. "Supercron E-415" (nonionic maleic anhydride-modified chlorinated polyolefin resin, melting point 60-80 ° C) is used in combination with calcium acetate monohydrate in place of "Orgatics ZB-126" An evaluation sample was obtained in the same manner as in Example 1 except that the pretreatment liquid composition shown in Table 1 was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

(Example 6)
In Example 1, instead of “Superflex 650” as the pretreatment liquid resin, “Pascor JK870” (cationic carbonate urethane resin, solid content 30 wt%) manufactured by Meisei Chemical Industry Co., Ltd. and “Supercron E” manufactured by Nippon Paper Industries Co., Ltd. -415 "(nonionic maleic anhydride-modified chlorinated polyolefin resin, melting point 60-80 ° C), and calcium acetate monohydrate is used in place of" Orgatrix ZB-126 ", as shown in Table 1. An evaluation sample was obtained in the same manner as in Example 1 except that the pretreatment liquid composition was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

(Example 7)
In Example 1, instead of “Superflex 650” as the resin for the pretreatment liquid, “Viniblanc 2687” (cationic acrylic resin) manufactured by Nissin Chemical Industry Co., Ltd. and “Supercron E-415” manufactured by Nippon Paper Industries Co., Ltd. (nonionic properties) In combination with a maleic anhydride-modified chlorinated polyolefin resin (melting point: 60 to 80 ° C.), and using calcium acetate monohydrate instead of “Orgatics ZB-126”, the pretreatment liquid composition shown in Table 1 was obtained. An evaluation sample was obtained in the same manner as in Example 1 except that. The results evaluated in the same manner as in Example 1 are shown in Table 1.

(Comparative Example 1)
In Example 1, instead of “Superflex 650” as a pretreatment liquid resin, “Pascall JK870” (cationic carbonate urethane resin, solid content 30 wt%) manufactured by Meisei Chemical Industry Co., Ltd. was used, and the pretreatment shown in Table 1 was used. An evaluation sample was obtained in the same manner as in Example 1 except that the liquid composition was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

(Comparative Example 2)
In Example 1, “Supercron E-415” (nonionic maleic anhydride-modified chlorinated polyolefin resin, melting point 60 to 80 ° C.) manufactured by Nippon Paper Industries Co., Ltd. was used instead of “Superflex 650” as the resin for the pretreatment liquid. An evaluation sample was obtained in the same manner as in Example 1 except that calcium acetate monohydrate was used instead of “Orgatics ZB-126” and the pretreatment liquid composition shown in Table 1 was used. The results evaluated in the same manner as in Example 1 are shown in Table 1.

(Reference Example 1)
In Comparative Example 1, an evaluation sample was obtained in the same manner as in Comparative Example 1 except that the film thickness (after drying) of the pretreatment layer was changed from 1.6 μm to 6.0 μm. The results evaluated in the same manner as in Example 1 are shown in Table 1.

<Evaluation>
From Table 1, in Examples 1 to 7 in which the pretreatment layer formed by the pretreatment liquid was a thin film because the swelling ratio A of the resin contained in the pretreatment liquid was greater than 100% and 500% or less, It can be seen that it is possible to achieve both image abrasion resistance, crack prevention and bleeding prevention.

On the other hand, it can be seen that in Comparative Example 1 in which the swelling ratio A of the resin exceeds 500%, crack prevention properties cannot be obtained. Note that the recording liquid set used in Comparative Example 1 has low versatility because the film thickness of the pretreatment layer must be increased (Reference Example 1) in order to obtain crack prevention. Further, when the film thickness is increased, there is a concern that the texture inherent to the non-absorbent base material may be impaired even if crack prevention is obtained.

On the other hand, in Comparative Example 2 where the resin does not swell (that is, the swelling ratio A = 100%), it can be seen that the anti-bleeding property cannot be obtained.

Claims (11)

A pretreatment liquid containing at least a flocculant and a resin;
An ink containing at least water, a colorant, a water-soluble solvent and a surfactant,
A recording liquid set in which a swelling ratio A represented by the following formula (1) of the resin contained in the pretreatment liquid is greater than 100% and 500% or less.
Swelling ratio A (%) = {(w2-w0) / (w1-w0)} × 100 (1)
[In the formula (1), w0 is the weight (g) of a 6 cm square non-absorbent substrate, and w1 is applied to the 6 cm square non-absorbent substrate so that the applied amount is 1.6 g / m ^2. The weight (g) of the dried test piece, and w2 is the weight (g) when the test piece is immersed in water for 10 minutes. ] The resin contained in the pretreatment liquid is
A resin having both a polar part and a non-polar part, or
2. The recording liquid set according to claim 1, which is a mixture of a resin having a polar part and a resin having a non-polar part. The resin contained in the pretreatment liquid is
A urethane resin having a swelling ratio A of more than 100% and 500% or less,
An acrylic resin having a swelling ratio A of more than 100% and 500% or less,
A mixture of an olefin resin and a urethane resin, or
3. The recording liquid set according to claim 1, wherein the recording liquid set is a mixture of an olefin resin and an acrylic resin. The recording liquid set according to claim 3, wherein the melting point of the olefin resin is 100 ° C or lower. Weight ratio of olefin resin and urethane resin in the mixture of olefin resin and urethane resin, or
The weight ratio of olefin resin to acrylic resin in the mixture of olefin resin and acrylic resin is
The recording liquid set according to claim 3, wherein the recording liquid set is 1: 9 to 8: 2. 6. The recording liquid set according to claim 3, wherein the olefin resin is a chlorinated polyolefin. An ink jet recording method using the recording liquid set according to any one of claims 1 to 6,
Applying the pretreatment liquid to a non-absorbent substrate and drying to form a pretreatment layer,
Next, an ink jet recording method for recording an image by applying the ink onto the pretreatment layer by an ink jet method. The ink jet recording method according to claim 7, wherein the film thickness of the pretreatment layer is 0.5 μm to 5 μm. The ink jet recording method according to claim 7 or 8, wherein an image is recorded by applying the ink onto the pretreatment layer by a one-pass method by the ink jet method. An ink containing at least water, a colorant, a water-soluble solvent and a surfactant;
A recording medium provided with a pretreatment layer containing at least a flocculant and a resin on the surface of the non-absorbent substrate;
An ink / recording medium set in which a swelling ratio A represented by the following formula (1) of the resin contained in the pretreatment layer is greater than 100% and 500% or less.
Swelling ratio A (%) = {(w2-w0) / (w1-w0)} × 100 (1)
[In the formula (1), w0 is the weight (g) of a 6 cm square non-absorbing recording medium, and w1 is applied to the 6 cm square non-absorbing recording medium so that the applied amount is 1.6 g / m ^2. The weight (g) of the dried test piece, and w2 is the weight (g) when the test piece is immersed in water for 10 minutes. ] The ink / recording medium set according to claim 10, wherein the film thickness of the pretreatment layer is 0.5 μm to 5 μm.