JP6740751B2 - Toner for developing electrostatic image and method for producing the same - Google Patents

Description

The present invention relates to an electrostatic charge image developing toner and a method for producing the same . More specifically, the present invention relates to a toner using an amorphous polyester resin, a crystalline polyester resin and a vinyl resin, and an electrostatic charge image developing toner capable of obtaining an image in which gloss is suppressed while maintaining low-temperature fixability and a toner thereof. It relates to a manufacturing method .

In recent years, in an electrophotographic image forming apparatus, an electrostatic charge image developing toner (hereinafter, also simply referred to as “toner”) having a better low-temperature fixability is provided in order to increase a printing speed and save energy. Is required. As such a toner, there is known a method in which a crystalline polyester resin having a sharp melt property is added as a fixing aid into a binder resin to lower the melting temperature and the melt viscosity of the binder resin to improve the low temperature fixability. Has been.
However, there is a concern that the melt viscosity of the binder resin may be lowered too much by simply adding the crystalline polyester resin. If the melt viscosity of the binder resin is too low, the gloss of the image becomes excessively high (glare occurs), and the image cannot be separated from the fixing member during high-speed printing, resulting in poor separation or hot offset. Occurs.
In order to solve the above problem, it is necessary to increase the elastic modulus of the toner at high temperature (90 to 120° C.).

Therefore, in order to solve the above problems, a method has been proposed in which an acrylic resin having a cross-linking structure derived from a cross-linking agent is added to the binder resin to increase the mechanical strength of the toner at high temperature (for example, Patent Document 1). See 1.).
However, since the acrylic resin has a crosslinked structure, it is difficult to melt even at high temperatures. Further, since the acrylic resin having a crosslinked structure has a network structure, it is difficult to be compatible with each other in the binder resin even when melted. Therefore, in the technique disclosed in Patent Document 1, the effect of increasing the elastic modulus at high temperature becomes small.

Further, in order to improve the compatibility between the amorphous polyester resin and the styrene/acrylic resin, a method using a styrene/acrylic resin containing 2-carboxyethyl acrylate as a polymerization component has been proposed (for example, Patent Document 2). reference.).
However, since 2-carboxyethyl acrylate has a polar group, when the toner is manufactured in an aqueous system, the styrene-acrylic resin tends to be unevenly present on the surface of the toner particles. That is, when 2-carboxyethyl acrylate is used, the high molecular weight polymer is unevenly distributed on the surface of the toner particles, and as a result, the meltability is affected and the low temperature fixability is impaired.

JP2012-108485A JP, 2015-179108, A

The present invention has been made in view of the above problems and circumstances, and a problem to be solved is to provide a toner using an amorphous polyester resin, a crystalline polyester resin, and a vinyl resin, while maintaining low-temperature fixability and gloss. It is an object of the present invention to provide an electrostatic charge image developing toner capable of obtaining a suppressed image and a method for producing the same.

In order to solve the above problems, the present inventor, in the process of examining the causes of the above problems, is a toner in which the weight average molecular weight of a component soluble in THF is within a specific range, and in addition to the crystalline polyester resin. By adding a vinyl resin having a high peak top molecular weight (Mp(s)) and a two-dimensional chain structure as a binder resin, the low temperature fixing property is maintained while the peak top molecular weight (Mp(s) is maintained at high temperature. The inventors have found that a vinyl resin having a high )) can increase the elastic modulus of the toner and suppress the gloss, and the present invention has been completed.
That is, the above-mentioned subject concerning the present invention is solved by the following means.

1. A toner for developing an electrostatic charge image, which comprises toner particles containing at least a binder resin, a release agent and a colorant,
The binder resin contains an amorphous polyester resin, a crystalline polyester resin, and a vinyl resin,
The amorphous polyester resin is an amorphous polyester resin composed of a polyvalent carboxylic acid and a polyhydric alcohol as a monomer,
The vinyl resin is a hybrid vinyl resin in which at least a vinyl polymerization segment and an amorphous polyester polymerization segment are bonded,
The content of the amorphous polyester resin in the binder resin is 50% by mass or more,
The weight average molecular weight (Mw(t)) of the component soluble in tetrahydrofuran (THF) measured by gel permeation chromatography (GPC) contained in the toner particles satisfies the following formula (1),
The vinyl resin has a peak top molecular weight (Mp(s)) satisfying the following formula (2),
And has a two-dimensional chain structure, and
A toner for developing an electrostatic charge image, wherein the vinyl resin has a structural unit derived from a (meth)acrylic acid alkyl ester-based monomer represented by the following structural formula (1).
Formula (1) Mw(t)<100000
Formula (2) 20000≦Mp(s)≦150,000
Structural formula _{(1) H 2 C = CR} 1 -COOR 2
[In the formula, R ₁ represents a hydrogen atom or a methyl group, and R ₂ represents an alkyl group having 6 to 22 carbon atoms. ]

2. The electrostatic charge image developing toner according to item 1, wherein the peak top molecular weight (Mp(s)) of the vinyl resin satisfies the following formula (3).
Formula (3) 30000≦Mp(s)≦100,000

3. The toner for developing an electrostatic image according to item 1 or 2, wherein the weight average molecular weight Mw(s) of the vinyl resin satisfies the following formula (4).
Formula (4) 80,000≦Mw(s)≦200000

4. Content of the said vinyl resin in the said binder resin exists in the range of 0.01-15 mass %, The electrostatic charge image as described in any one of the 1st term to the 3rd term characterized by the above-mentioned. Toner for development.

5 . The electrostatic charge image developing toner according to any one of items 1 to 4, wherein R ₂ in the structural formula (1) has a branched structure.

6 . The softening point T _sp vinyl resin, the toner for electrostatic image development according to any one of the first term and satisfies the following formula (5) to the fifth term.
Formula (5) 100° C.≦T _sp ≦120° C.

7. A method for producing an electrostatic charge image developing toner for producing the electrostatic charge image developing toner according to any one of items 1 to 6,
The amorphous polyester resin, the crystalline polyester resin, and a dispersion of resin particles of a vinyl resin, and the fine particle dispersion of each of the release agent and the colorant are mixed and aggregated to control the shape of the toner particles. A method for producing a toner for developing an electrostatic charge image, which comprises the steps of:

By the above means of the present invention, in a toner using an amorphous polyester resin, a crystalline polyester resin and a vinyl resin, an electrostatic charge image developing toner capable of obtaining an image in which gloss is suppressed while maintaining low-temperature fixability, and production thereof A method can be provided.
The mechanism of action or mechanism of action of the present invention has not been clarified, but is considered as follows.

First, the peak-top molecular weight (Mp(s)) of the weight average molecular weight (Mw(t)) of the component soluble in tetrahydrofuran (THF) satisfies the formula (1) and the vinyl resin satisfies the formula (2). The reason for having the following is considered as follows.
By including a crystalline polyester resin in the toner as a fixing aid, the low temperature fixability can be improved while maintaining the heat resistant storage property. As described above, the reason why the low-temperature fixability is improved is that the crystalline polyester resin is rapidly melted near the melting point of the crystalline polyester resin and is compatible with the amorphous polyester resin, and thus the toner near the fixing temperature is This is because the elastic modulus becomes low. Here, when the weight average molecular weight of the binder resin included in the toner (that is, the weight average molecular weight (Mw(t)) of the component soluble in tetrahydrofuran (THF)) exceeds 100,000, the temperature is low (40 to 70° C.). And the low temperature fixing property deteriorates. Therefore, the weight average molecular weight (Mw(t)) of the component soluble in THF needs to be 100,000 or less from the viewpoint of improving low-temperature fixability.
However, the inclusion of the crystalline polyester resin reduces the elastic modulus of the toner and improves the low-temperature fixability, but the fixed image becomes smoother and the glossiness becomes extremely high.

Therefore, the inventor of the present invention considered that a vinyl resin having a higher molecular weight than the amorphous polyester resin or the crystalline polyester resin should be added to the binder resin. Such a vinyl resin does not melt at a low temperature because it has a high molecular weight, and the elastic modulus of the toner does not increase near the fixing temperature, so that the low temperature fixability is not impaired. On the other hand, the vinyl resin melts at a high temperature and increases the elastic modulus of the toner, so that gloss in a fixed image can be suppressed.

When the peak top molecular weight (Mp(s)) of the vinyl resin is less than 20000, the vinyl resin is melted even at a low temperature and the elastic modulus of the toner is increased, so that the low temperature fixability is deteriorated. Further, when the peak top molecular weight (Mp(s)) of the vinyl resin exceeds 150,000, the vinyl resin does not melt even at a high temperature, and the effect of suppressing gloss due to the increased elastic modulus is not exhibited. Therefore, the peak top molecular weight (Mp(s)) of the vinyl resin needs to be 20,000 to 150,000.

Next, the reason why the vinyl resin should have a two-dimensional chain structure is considered as follows.
First, that the vinyl resin “has a two-dimensional chain structure” means that the vinyl resin does not have a so-called three-dimensional crosslinked structure to which a crosslinking agent is added.
A vinyl resin (hereinafter, also referred to as “crosslinked vinyl resin”) mainly having a three-dimensional crosslinked structure (hereinafter, simply referred to as “crosslinked structure”) to which a crosslinking agent is added is a vinyl resin having a two-dimensional chain structure. Compared with the above, the meltability by heat is lowered and it becomes difficult to melt even at high temperature. In addition, the three-dimensional crosslinked structure has a network structure, unlike the two-dimensional chain structure, so that the crosslinked vinyl resin is compatible with the amorphous polyester resin, which is the main component of the binder resin, even when melted. difficult. Therefore, in the toner having the crosslinked vinyl resin, it is difficult to exhibit the effect of increasing the elastic modulus at high temperature, so that the effect of suppressing gloss cannot be obtained.
On the other hand, when the vinyl resin mainly composed of the two-dimensional chain structure is melted, it is easily compatible with the amorphous polyester resin which is the main component of the binder resin, so that the elastic modulus is increased at a high temperature to suppress the gloss The effect is obtained.

Therefore, the vinyl resin is required to have a two-dimensional chain structure containing no cross-linking agent. However, if most of the crystal structure is a two-dimensional chain structure, it is considered that a part of the crystal structure may include a three-dimensional bridge. Examples of the cross-linking agent include diacrylate compounds, dimethacrylate compounds, divinylbenzene, and the like, and the vinyl resin of the present invention has a monomer composition that does not include these cross-linking agents.
As described above, in the toner having the constitution of the present invention including the amorphous polyester resin, the crystalline polyester resin, and the vinyl resin as the binder resin, it is possible to obtain an image in which gloss is suppressed while maintaining low-temperature fixability.

The electrostatic image developing toner of the present invention is an electrostatic image developing toner having toner particles containing at least a binder resin, a release agent and a colorant, wherein the binder resin is an amorphous polyester resin. And a crystalline polyester resin and a vinyl resin, the amorphous polyester resin is an amorphous polyester resin composed of a polyvalent carboxylic acid and a polyhydric alcohol as a monomer, and the vinyl resin is A hybrid vinyl resin in which at least a vinyl-polymerized segment and an amorphous polyester-polymerized segment are bonded, and the content of the amorphous polyester resin in the binder resin is 50% by mass or more, and the toner The weight average molecular weight (Mw(t)) of the component soluble in tetrahydrofuran (THF) measured by gel permeation chromatography (GPC) contained in the particles satisfies the above formula (1), and the vinyl resin is It has a peak top molecular weight (Mp(s)) satisfying the formula (2) and has a two-dimensional chain structure, and the vinyl resin is a (meth)acryl represented by the structural formula (1). It is characterized by having a structural unit derived from an acid alkyl ester-based monomer. This feature is a technical feature common to or corresponding to the invention according to each claim. As a result, in the toner using the amorphous polyester resin, the crystalline polyester resin, and the vinyl resin, it is possible to obtain an effect that an image in which gloss is suppressed while maintaining low-temperature fixability is obtained.

It is preferable that the peak top molecular weight (Mp(s)) of the vinyl resin satisfies the above formula (3). Thereby, the low temperature fixability and the suppression of gloss can be further improved.

It is preferable that the weight average molecular weight Mw(s) of the vinyl resin satisfies the above formula (4). Thereby, the low temperature fixability and the suppression of gloss can be further improved.

The content of the vinyl resin in the binder resin is preferably in the range of 0.01 to 15% by mass. Thereby, the low temperature fixability and the suppression of gloss can be further improved.

The vinyl resin preferably has a structural unit derived from the (meth)acrylic acid alkyl ester-based monomer represented by the structural formula (1). Thereby, the low temperature fixability can be further improved.

R ₂ in the structural formula (1) preferably has a branched structure. Since such a vinyl resin has a high affinity with the crystalline resin, it is possible to suppress the crystallization of the crystalline polyester resin, and as a result, it is possible to uniformly disperse the crystalline domains of the crystalline resin. As a result, the low temperature fixability is suitably improved.

It is preferable that the toner particles have a core-shell structure including a shell layer that covers the surface of the core, and the vinyl resin is contained in the core. Thereby, the low temperature fixability can be further improved while maintaining the heat resistant storage property.

It is preferable that the softening point T _{sp of the} vinyl resin satisfies the above formula (5). Thereby, the low temperature fixability and the suppression of gloss can be further improved.

It is preferable that the vinyl resin is a hybrid vinyl resin in which at least a vinyl polymer segment and an amorphous polyester polymer segment are bonded. Thereby, the low temperature fixability and the suppression of gloss can be further improved.

Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In addition, in this application, "-" is used in the meaning including the numerical value described before and after that as a lower limit and an upper limit.

In the present application, the peak top molecular weight (Mp(s)) refers to the molecular weight at the maximum point of the peak having the largest molecular weight among the peaks measured by gel permeation chromatography (GPC).

The gel permeation chromatography (GPC) is not particularly limited and can be performed by using a known method. Specifically, it is carried out by flowing tetrahydrofuran (THF) as a solvent into a column and injecting a THF solution of a sample (toner particles, vinyl resin, etc.).
The molecular weight of the sample (weight average molecular weight Mw and number average molecular weight Mn) can be measured using a refractive index detector. Further, the molecular weight distribution of the sample can be calculated using a calibration curve prepared from a monodisperse polystyrene standard sample, and the peak top molecular weight (Mp(s)) can be determined from the molecular weight distribution.

[Toner for developing electrostatic image]
The electrostatic image developing toner of the present invention (hereinafter, also simply referred to as “toner”) has toner particles containing at least a binder resin, a release agent and a colorant.
In the present invention, the “toner” refers to an aggregate of “toner particles”.

[Toner particles]
The toner particles according to the present invention contain a binder resin, a release agent and a colorant. In particular, it is preferable that the toner particles according to the present invention have an embodiment having toner base particles containing a binder resin, a release agent and a colorant.
Here, the “toner base particles” are particles containing at least a binder resin, a release agent and a colorant. The toner base particles can be used as the toner particles as they are, but it is usually preferable to use the toner particles to which external additives are added. In the following description, the toner base particles and the toner particles are simply referred to as “toner particles” unless it is necessary to distinguish them.

The toner particles according to the present invention have a weight average molecular weight of a component soluble in tetrahydrofuran (THF) (hereinafter, also referred to as “THF soluble component”) measured by gel permeation chromatography (GPC) as represented by the following formula (1). Fulfill.

Formula (1) Mw(t)<100000

The molecular weight measurement by GPC can be performed by a known method using a THF-soluble component contained in toner particles as a measurement sample.

[Binder resin]
The binder resin contains an amorphous polyester resin, a crystalline polyester resin, and a vinyl resin. It should be noted that other resins, compounds, and the like may be contained within a range that does not impair the manifestation of the effects of the present invention.

[Vinyl resin]
The vinyl resin is a polymer of a monomer having a vinyl group (hereinafter referred to as vinyl monomer).
Examples of vinyl resins that can be used include styrene/acrylic resins, styrene resins, and acrylic resins. Among them, structural units derived from the (meth)acrylic acid alkyl ester-based monomer represented by the following structural formula (1) are used. It is preferable to have.

Structural formula _{(1) H 2 C = CR} 1 -COOR 2
[In the formula, R ₁ represents a hydrogen atom or a methyl group, and R ₂ represents an alkyl group having 6 to 22 carbon atoms. ]

If a vinyl resin having a high peak top molecular weight (Mp(s)) is present in the surface layer of the toner particles, it affects the meltability of the toner, and therefore is unevenly distributed on the center side of the toner (in the core or shell, the core). Preferably.
Here, when the toner is produced in an aqueous system, if the vinyl resin has a polar group, the vinyl resin is likely to be distributed on the surface layer of the toner particles, and as a result, the vinyl resin may be present on the surface layer of the toner particles. Get higher Therefore, the vinyl resin has a structural unit derived from the (meth)acrylic acid alkyl ester-based monomer represented by the structural formula (1) having no polar group, and that the vinyl resin is present on the surface layer of the toner particles. Is preferable since it can be avoided.
The surface layer of the toner particles means a portion from the outermost surface to 20% of the particle diameter.

Further, R ₂ in the structural formula (1) preferably has a branched structure. With such a vinyl resin, the affinity with the crystalline resin is increased, and by suppressing the crystallization of the crystalline polyester resin, it is possible to uniformly finely disperse the crystalline domains of the crystalline resin. Further, low temperature fixability can be made more suitable.

Specific examples of the structural formula (1) include 2-ethylhexyl acrylate if it is branched and lauryl acrylate if it is not branched. Not limited.

The vinyl resin according to the present invention has a two-dimensional chain structure.
The fact that the vinyl resin has a two-dimensional chain structure can be realized by not actively forming a crosslinked structure during the synthesis of the vinyl resin. That is, the vinyl resin according to the present invention has a monomer composition containing no crosslinking agent. Examples of the cross-linking agent include diacrylate compounds, dimethacrylate compounds, divinylbenzene, and the like, and also those described in paragraph 0018 of JP 2012-108485 A.
Since the vinyl resin according to the present invention has almost no crosslinked structure, it is considered that the crosslink density is very low, for example, 10% or less. However, in general, the crosslink density can be determined by viscoelasticity measurement, but since the vinyl resin according to the present invention has no or little crosslinkage, it is considered that the crosslink density cannot be determined by viscoelasticity measurement.
Further, the vinyl resin according to the present invention does not have a cross-linking structure, and is soluble in THF. From this, it is considered that the toner of the present invention contains almost no resin that becomes a THF-insoluble matter.

Further, the vinyl resin according to the present invention has a peak top molecular weight (Mp(s)) satisfying the following formula (2).

Formula (2) 20000≦Mp(s)≦150,000

Here, the peak top molecular weight (Mp(s)) refers to the molecular weight at the maximum point of the peak having the largest molecular weight among the peaks measured by gel permeation chromatography (GPC) as described above.

The peak top molecular weight (Mp(s)) of the vinyl resin preferably satisfies the following formula (3).
Formula (3) 30000≦Mp(s)≦100,000
Within the range of the above formula (3), it is possible to prevent the vinyl resin from melting on the low temperature side, and as a result, the elastic modulus of the toner does not increase and the low temperature fixability can be further improved. Further, since it melts favorably on the high temperature side, the elastic modulus becomes high, and as a result, the effect of suppressing gloss can be more suitably exhibited. It is preferable that the Mw(s) of the vinyl resin also satisfies the following formula (4) for the same reason.
Formula (4) 80,000≦Mw(s)≦200000

Acrylic polymerizable monomers (vinyl monomers) for synthesizing styrene-acrylic resins include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-methacrylate. Methacrylic acid ester derivatives such as butyl, n-octyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, lauryl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, dimethylaminoethyl methacrylate; methyl acrylate, ethyl acrylate , Isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-octyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, lauryl acrylate, phenyl acrylate derivatives Among them, butyl acrylate, 2-ethylhexyl acrylate and methyl methacrylate, which are hydrophobic monomers, and acrylic acid and methacrylic acid, which have a carboxy group which is an ionic dissociative group, are particularly preferably used. These can be used alone or in combination of two or more.

Examples of the styrene-polymerizable monomer (vinyl monomer) for synthesizing a styrene-acrylic resin include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p- Phenyl styrene, p-ethyl styrene, 2,4-dimethyl styrene, p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, Examples thereof include styrene and styrene-styrene derivatives such as pn-dodecylstyrene, and it is particularly preferable to use styrene which is a hydrophobic monomer. These can be used alone or in combination of two or more.

The styrene/acrylic resin is preferably a copolymer of styrene polymerizable monomers, and particularly preferably a copolymer of styrene and (meth)acrylic acid. In this case, the preferable copolymerization ratio of the acrylic polymerizable monomer and the styrene polymerizable monomer is preferably 80:20 to 10:90 on a mass basis. By setting such a copolymerization ratio, the copolymerization composition ratio in each toner particle can be made uniform.

The styrene-acrylic resin can be produced by a known method, for example, an emulsion polymerization method or the like.
As the radical polymerization initiator used when the emulsion polymerization method is used, any appropriate water-soluble polymerization initiator can be used, and specifically, for example, 2,2′-azobis[2 -(2-Imidazolin-2-yl)propane] dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] disulfate anhydride, 2,2'-azobis(2 -Methylpropionamidine) dihydrochloride, 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] hydrate, 2,2'-azobis{2-[1-(2- Hydroxyethyl)-2-imidazolin-2-yl]propane} dihydrochloride, 2,2′-azobis[2-(2-imidazolin-2-yl)propane], 2,2′-azobis(1-imino-) 1-pyrrolidino-2-ethylpropane) dihydrochloride, 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide}, 2,2' -Azobis[2-methyl-N-(2-hydroxyethyl)propionamide] and other water-soluble azo initiators; persulfates such as potassium persulfate and ammonium persulfate, azobisaminodipropane acetate, azobiscyanovaleric acid and the like Examples thereof include water-soluble polymerization initiators such as salts and hydrogen peroxide. These can be used alone or in combination of two or more.

In the process of producing the styrene-acrylic resin according to the present invention, a commonly used chain transfer agent can be used for the purpose of adjusting the molecular weight of the acrylic resin. The chain transfer agent is not particularly limited, and examples thereof include mercaptans such as 2-chloroethanol, octyl mercaptan, dodecyl mercaptan, and t-dodecyl mercaptan, and styrene dimer.

The vinyl resin according to the present invention, in order to synthesize the styrene-acrylic resin, in addition to vinyl monomers such as styrene-polymerizable monomers and acrylic-polymerizable monomers, the following vinyl monomers are polymerized. It may be

(1) Vinyl esters, vinyl propionate, vinyl acetate, vinyl benzoate, etc. (2) Vinyl ethers, vinyl methyl ether, vinyl ethyl ether, etc. (3) Vinyl ketones, vinyl methyl ketone, vinyl ethyl ketone, vinyl hexyl ketone, etc. (4) N-vinyl compounds N-vinylcarbazole, N-vinylindole, N-vinylpyrrolidone, etc. (5) Other vinyl compounds such as vinylnaphthalene and vinylpyridine, acrylic acid such as acrylonitrile, methacrylonitrile and acrylamide, methacrylic acid derivatives etc

As the vinyl monomer, a monomer having an ionic dissociative group such as a carboxy group, a sulfonic acid group or a phosphoric acid group can be used because the affinity with the crystalline resin can be easily controlled.
Examples of the monomer having a carboxy group include acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumaric acid, maleic acid monoalkyl ester and itaconic acid monoalkyl ester.
Examples of the monomer having a sulfonic acid group include styrenesulfonic acid, allylsulfosuccinic acid, 2-acrylamido-2-methylpropanesulfonic acid and the like.
Examples of the monomer having a phosphoric acid group include acid phosphooxyethyl methacrylate.

The above vinyl monomers may be used alone or in combination of two or more.

The vinyl resin according to the present invention preferably has a tetrahydrofuran (THF) insoluble content (gel content) of 0.5 to 50% by mass.
The THF insoluble content in the vinyl resin indicates the content of the crosslinking component in the toner particles, and if it is less than 0.5% by mass, good high temperature offset resistance may not be obtained, If it exceeds 50% by mass, the progress of fusion is slowed during the production of the toner, and the production load may increase.

The THF insoluble content of the vinyl resin was determined by immersing a predetermined amount (about 0.03 g) of the sample in a predetermined amount (about 100 mL) of THF for 20 hours using a solid vinyl resin as a measurement sample, and then using a wire mesh of 120 mesh. It is obtained by filtering and calculating the mass% of the obtained residual solid content with respect to the sample.

Glass transition temperature of the vinyl resin _{(T g)} is preferably from 20 to 120 ° C., it is particularly preferably 35 to 100 ° C..
As for the softening point of the vinyl resin, it is preferable that the softening point T _sp of the vinyl resin satisfies the following formula (5).

Formula (5) 100° C.≦T _sp ≦120° C.

When the softening point of the vinyl resin is 100° C. or higher, it is possible to prevent the vinyl resin having a high peak top molecular weight (Mp(s)) from being melted at a low temperature when the toner is melted. As a result, it is possible to prevent the viscoelasticity of the toner from increasing, so that the meltability of the toner can be made suitable. On the other hand, when the softening point is 120° C. or lower, the resin melts favorably even at a high temperature, so that the effect of incorporating a vinyl resin having a high peak top molecular weight (Mp(s)) is not hindered.

The content of the vinyl resin in the binder resin is preferably in the range of 0.01 to 15% by mass. When the content of the vinyl resin is 0.01% by mass or more, the elastic modulus of the toner is increased on the high temperature side, and the effect of suppressing gloss is suitably exhibited. When the content is 15% by mass or less, the crystalline polyester resin can be appropriately dispersed, and as a result, the low temperature fixability is not impaired.

The glass transition point (T _g ) can be measured using a differential scanning calorimeter, for example, a diamond DSC (manufactured by Perkin Elmer). Specifically, 3.0 mg of the sample is enclosed in an aluminum pan, and the temperature is changed in the order of heating, cooling, and heating. The temperature was raised from room temperature (25° C.) during the first heating to 0° C. during the second heating to 200° C. at a heating rate of 10° C./min, and 150° C. was maintained for 5 minutes. During cooling, the temperature was decreased from 200° C. to 0° C. at a temperature decrease rate of 10° C./min, and the temperature of 0° C. was maintained for 5 minutes. The shift of the baseline was observed in the measurement curve obtained during the second heating, and the intersection point between the extension line of the baseline before shifting and the tangent line indicating the maximum slope of the shifted portion of the baseline was taken as the glass transition point (T _g ). An empty aluminum pan is used as a reference.

The softening point can be measured by a known method, for example, by performing a temperature rise method test with a flow tester “CFT-500D” (manufactured by Shimadzu Corporation).

<Hybrid vinyl resin>
The vinyl resin may be a hybrid vinyl resin in which at least a vinyl polymer segment and an amorphous polyester polymer segment are bonded. Since the vinyl resin is a hybrid vinyl resin with an amorphous polyester resin, the dispersed state in the toner particles is improved. As a result, the effect of adding the vinyl resin to the entire toner is exhibited, which is preferable.

Here, the “hybrid vinyl resin” refers to an amorphous polyester molecular chain (hereinafter also referred to as an amorphous polyester polymerization segment) and a vinyl molecular chain such as a styrene-acrylic copolymer molecular chain (hereinafter, “ (Also referred to as “vinyl polymerized segment”) is a resin (hybrid resin) composed of polyester molecules having a structure in which molecular bonds are formed. That is, the hybrid vinyl resin is a resin having a copolymer structure in which a vinyl polymer segment is molecularly bonded to an amorphous polyester polymer segment.
The vinyl resin is a resin containing a hybrid vinyl resin having a structure in which a vinyl molecular chain is molecularly bonded to such a polyester molecular chain, that is, a resin in which a hybrid vinyl resin and other resin are molecularly bonded. May be.

Here, the hybrid vinyl resin used as the vinyl resin is clearly a hybrid resin of a crystalline polyester resin and an amorphous resin described below (hereinafter, also simply referred to as “crystalline hybrid polyester resin”) in the following points. To be distinguished. That is, unlike the crystalline polyester resin segment that constitutes the crystalline hybrid polyester resin, the amorphous polyester polymerized segment that constitutes the hybrid vinyl resin does not have a clear melting point and has a relatively high glass transition temperature (T _g ) Is an amorphous molecular chain. This can be confirmed by performing differential scanning calorimetry (DSC) on the toner. Further, since the monomer (chemical structure) that constitutes the amorphous polyester polymer segment is different from the monomer (chemical structure) that constitutes the crystalline polyester resin segment, it is also distinguished by analysis such as NMR. be able to.

The amorphous polyester polymerized segment is formed by a polyhydric alcohol monomer and a polycarboxylic acid monomer.

The polyhydric alcohol monomer is not particularly limited, but is preferably an aromatic diol or a derivative thereof from the viewpoint of chargeability and toner strength. For example, bisphenols such as bisphenol A and bisphenol F And alkylene oxide adducts of bisphenols such as ethylene oxide adducts and propylene oxide adducts thereof.
Among these, as the polyhydric alcohol monomer, particularly from the viewpoint of improving the charging uniformity of the toner, 2,2-bis(4-hydroxyphenyl)propane ethylene oxide and 2,2-bis(4-hydroxy) are used. It is preferable to use ethylene oxide adduct and propylene oxide adduct of bisphenol A such as phenyl)propane propylene oxide. These polyhydric alcohol monomers may be used alone or in combination of two or more.

Examples of the polycarboxylic acid monomer to be condensed with the polyhydric alcohol monomer include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic acid anhydride, pyromellitic acid, and naphthalenedicarboxylic acid. And aliphatic carboxylic acids such as fumaric acid, maleic anhydride, and alkenylsuccinic acid; and lower alkyl esters and acid anhydrides of these acids, and these may be used alone or in combination of two or more.

(Method for forming amorphous polyester polymerized segment)
The method for forming the amorphous polyester polymerized segment is not particularly limited, and the amorphous polyester polymerized by polycondensing (esterifying) the polyvalent carboxylic acid and the polyhydric alcohol using a known esterification catalyst. Segments can be formed.

Known esterification catalysts that can be used in the formation of the amorphous polyester polymerized segment include alkali metal compounds such as sodium and lithium; alkaline earth metal compounds such as magnesium and calcium; aluminum, zinc, manganese, antimony, Examples thereof include metal compounds such as titanium, tin, zirconium, and germanium; phosphorous acid compounds; phosphoric acid compounds; amine compounds. Among them, Ti(OBu) ₄ is preferable. You may use these individually by 1 type or in combination of 2 or more types.

The polymerization temperature is not particularly limited, but it is preferably 150 to 250°C. The polymerization time is not particularly limited, but it is preferably 0.5 to 10 hours. During the polymerization, the pressure inside the reaction system may be reduced if necessary.

(Vinyl polymerized segment)
The vinyl polymer segment is not particularly limited, but is preferably one formed by addition-polymerizing at least a styrene monomer and a (meth)acrylic acid ester monomer. The styrene monomer mentioned here includes, in addition to styrene represented by the structural formula of CH ₂ ═CH—C ₆ H ₅ , those having a known side chain or functional group in the styrene structure. Further, the (meth)acrylic acid ester monomer referred to here is represented by the structural formula (1) in addition to the acrylic acid ester represented by CH ₂ ═CHCOOR (R is an alkyl group) and the methacrylic acid ester. (Meth)acrylic acid alkyl ester monomer, acrylic acid ester derivative, methacrylic acid ester derivative or the like having a known side chain or functional group-containing ester in its structure.
Specifically, styrene, acrylic acid, 2-ethylhexyl acrylate and the like can be preferably used.

Specific examples of the styrene monomer and (meth)acrylic acid ester monomer capable of forming the vinyl polymer segment include, for example, the above-mentioned styrene polymerizable monomer and paragraph 0073 to JP-A-2016-31460. Although those described in 0077 and the like can be preferably used, those usable for forming the vinyl polymer segment used in the present invention are not limited thereto.

In addition, in this specification, "(meth)acrylic acid ester monomer" is a generic term for "acrylic acid ester monomer" and "methacrylic acid ester monomer". “Methyl acrylate” is a generic term for “methyl acrylate” and “methyl methacrylate”.

These acrylic acid ester monomers or methacrylic acid ester monomers can be used alone or in combination of two or more kinds. That is, a copolymer is formed by using a styrene monomer and two or more kinds of acrylic acid ester monomers, and a copolymer is formed by using a styrene monomer and two or more kinds of methacrylic acid ester monomers. It is possible either to form a combination or to form a copolymer by using a styrene monomer and an acrylic acid ester monomer and a methacrylic acid ester monomer in combination.

The content of the structural unit derived from the styrene monomer in the vinyl polymer segment is preferably in the range of 40 to 90 mass% with respect to the total amount of the vinyl polymer segment. The content of the constituent unit derived from the (meth)acrylic acid ester monomer in the vinyl polymer segment is preferably in the range of 10 to 60 mass% with respect to the total amount of the vinyl polymer segment. By setting it within such a range, it becomes easy to control the plasticity of the hybrid vinyl resin.

Further, the vinyl polymerized segment is preferably obtained by addition-polymerizing a compound for chemically bonding to the amorphous polyester polymerized segment in addition to the styrene monomer and the (meth)acrylic acid ester monomer. Specifically, it is preferable to use a compound contained in the amorphous polyester polymerized segment and forming an ester bond with a hydroxy group [-OH] derived from a polyhydric alcohol or a carboxy group [-COOH] derived from a polyvalent carboxylic acid. Therefore, the vinyl polymer segment is a compound that is addition-polymerizable with a styrene monomer and a (meth)acrylic acid ester monomer and has a carboxyl group [-COOH] or a hydroxy group [-OH]. Further polymerization is preferable.

Examples of such a compound include a compound having a carboxy group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, cinnamic acid, fumaric acid, maleic acid monoalkyl ester, itaconic acid monoalkyl ester; 2-hydroxy. Ethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate And a compound having a hydroxy group such as polyethylene glycol mono(meth)acrylate.

The content of the structural unit derived from the above compound in the vinyl polymer segment is preferably in the range of 0.5 to 20 mass% with respect to the total amount of the vinyl polymer segment.

The method for forming the vinyl polymer segment is not particularly limited, and examples thereof include a method of polymerizing a monomer using a known polymerization initiator. Specific examples of such a polymerization initiator include those described in JP-A-2016-31460, paragraph 0081, but are not limited thereto.

(Method for producing hybrid vinyl resin)
The method for producing the hybrid vinyl resin is not particularly limited, and a known method can be used. Specifically, for example, the method described in paragraphs 0060 to 0068 of JP-A-2016-31460 can be used, but the method is not limited thereto.

[Amorphous polyester resin]
In the present invention, the content of the amorphous polyester resin in the binder resin is 50% by mass or more. The toner according to the present invention preferably contains the amorphous polyester resin in the range of 60 to 80% by mass with respect to the total binder resin. That is, it is preferable that, within 100 parts by mass of the binder resin according to the present invention, the range of 60 to 80 parts by mass is the amorphous polyester resin. When it is 80% by mass or less, the ratio of the crystalline resin can be made sufficient, and more suitable low temperature fixability can be obtained.

The amorphous polyester resin is a non-crystalline polyester resin obtained by a polymerization reaction of a divalent or higher carboxylic acid (polyvalent carboxylic acid) monomer and a divalent or higher valent alcohol (polyhydric alcohol) monomer. It is a resin that exhibits crystallinity. The amorphous polyester resin can be formed by polymerizing (esterifying) the below-described polyvalent carboxylic acid monomer and polyhydric alcohol monomer using a known esterification catalyst.

The polycarboxylic acid monomer is a compound containing two or more carboxy groups in one molecule.
The polycarboxylic acid monomer that can be used in the synthesis of the amorphous polyester resin is not particularly limited, and known ones can be used, for example, the same ones that can be used for the amorphous polyester polymer segment are used. it can.

The polyhydric alcohol monomer is a compound containing two or more hydroxy groups in one molecule.
The polyhydric alcohol monomer that can be used in the synthesis of the amorphous polyester resin is not particularly limited, and known ones can be used, for example, the same ones that can be used for the amorphous polyester polymer segment can be used. ..

The esterification catalyst that can be used is not particularly limited, and known ones can be used, for example, the same ones that can be used for the amorphous polyester polymerized segment can be used.

The polymerization temperature is not particularly limited, but is preferably in the range of 150 to 250°C. The polymerization time is not particularly limited, but is preferably within the range of 0.5 to 10 hours. During the polymerization, the pressure inside the reaction system may be reduced if necessary.

The glass transition point (T _g ) of the amorphous resin is preferably 25 to 60° C., and more preferably 35 to 55° C. from the viewpoint of achieving both sufficient low temperature fixability and heat resistant storage stability.

The weight average molecular weight (Mw) of the amorphous polyester resin can be in the range of 10,000 to 100,000.

When the acid value of the amorphous polyester resin is smaller than the acid value of the crystalline polyester resin, the dispersibility of the crystalline polyester resin can be sufficiently enhanced, which is preferable.
The acid value of the amorphous polyester resin can be measured according to the method (potentiometric titration method) described in JIS K0070-1992. In the measurement, the solvent used is a mixture of tetrahydrofuran and isopropyl alcohol in a volume ratio of 1:1.

[Crystalline polyester resin]
The crystalline polyester resin is one of the binder resins, and any known crystalline polyester resin can be used without limitation as long as it is a crystalline polyester resin. "Crystallinity" means having a clear endothermic peak at the melting point, that is, at the time of temperature rise in the endothermic curve obtained by DSC. The definite endothermic peak refers to a peak having a half width within 15° C. in the endothermic curve when the temperature is raised at a heating rate of 10° C./min.

From the viewpoint of obtaining excellent low-temperature fixability, the content of the crystalline polyester resin in the toner particles is preferably in the range of 1 to 30% by mass, and is preferably in the range of 5 to 20% by mass. More preferable.
When the content is 1% by mass or more, sufficient low-temperature fixability can be obtained, and when the content is 30% by mass or less, scattering of toner due to decrease in charging property can be suppressed.

The crystalline polyester resin is specifically a polyester resin obtained by a polymerization reaction between a divalent or higher carboxylic acid (polyvalent carboxylic acid) monomer and a divalent or higher valent alcohol (polyhydric alcohol) monomer. Among them, a resin exhibiting crystallinity.
The crystalline polyester resin is a polyvalent carboxylic acid monomer and a polyhydric alcohol monomer which can be used in the synthesis of the crystalline polyester resin described below by using a known esterification catalyst in the same manner as the above-mentioned amorphous polyester resin. It can be formed using a polymer.

Examples of the polycarboxylic acid monomer that can be used in the synthesis of the crystalline polyester resin include oxalic acid, malonic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, n-dodecylsuccinic acid, 1,10-decanedicarboxylic acid. Saturated aliphatic dicarboxylic acids such as acids (dodecanedioic acid) and 1,12-dodecanedicarboxylic acid (tetradecanedioic acid); alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid; aromatics such as phthalic acid, isophthalic acid and terephthalic acid Dicarboxylic acids; trivalent or higher polycarboxylic acids such as trimellitic acid and pyromellitic acid; anhydrides of these carboxylic acid compounds and alkyl esters having 1 to 3 carbon atoms.
These may be used alone or in combination of two or more.

Examples of the polyhydric alcohol monomer that can be used for synthesizing the crystalline polyester resin include 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6. Aliphatic diols such as -hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, neopentyl glycol, 1,4-butenediol; glycerin, pentaerythritol, trimethylolpropane, Examples thereof include polyhydric alcohols having 3 or more valences such as sorbitol.
These may be used alone or in combination of two or more.

(Hybrid crystalline polyester resin)
The crystalline polyester resin is preferably a hybrid resin of a crystalline polyester resin and an amorphous resin.
Such a hybrid crystalline polyester resin can adjust the affinity with the amorphous resin so that the crystalline resin is finely dispersed in the amorphous resin uniformly.

In the above hybrid crystalline polyester resin, a resin portion having a structure derived from a crystalline Poerister resin is called a crystalline polyester resin segment, and a resin portion having a structure derived from an amorphous resin is called an amorphous resin segment.
Since the hybrid crystalline polyester resin has a high affinity with the amorphous resin in which the amorphous resin segment is the matrix phase, the molecular chains of the crystalline resin segment are likely to be arranged, and sufficient crystallinity may be exhibited. it can.

The content of the crystalline polyester resin segment in the hybrid crystalline polyester resin is preferably in the range of 50 to 98% by mass from the viewpoint of imparting sufficient crystallinity to the hybrid crystalline polyester resin.
The constituents and contents of each segment such as the crystalline polyester resin segment in the hybrid crystalline polyester resin are, for example, NMR analysis, methylation reaction pyrolysis gas chromatography/mass spectrometry (Py-GC/MS: Pyrolysis Gas Chromatography). It can be measured by Mass Spectrometry) or the like.

The amorphous resin segment is not particularly limited as long as it exhibits amorphousness, and examples thereof include an amorphous vinyl resin segment, an amorphous urethane resin segment, and an amorphous urea resin segment. Among them, when the amorphous resin segment has a structure derived from an amorphous resin such as an amorphous vinyl resin or an amorphous polyester resin used as a binder resin, it has an amorphous resin which is a matrix phase. Compatibility is improved, and charging uniformity and the like can be obtained.
The content of the amorphous resin segment in the hybrid crystalline polyester resin can be in the range of 40 to 60% by mass, and is preferably in the range of 45 to 50% by mass.

Examples of the method for synthesizing the hybrid crystalline polyester resin include the following synthetic methods (1) to (3).
(1) A crystalline polyester resin segment is made amorphous by reacting a monomer that is a raw material of the amorphous resin after reacting a bireactive monomer with a crystalline polyester resin prepared in advance. Method of chemically bonding resin segment (2) After reacting a bireactive monomer with a non-crystalline resin prepared in advance, a polyvalent carboxylic acid monomer and a polyhydric alcohol which are raw materials of a crystalline polyester resin A method of reacting a monomer to chemically bond the crystalline polyester resin segment to the amorphous resin segment (3) Reacting the previously prepared crystalline polyester resin and amorphous resin with the bireactive monomer And chemically bond each as a segment

Among them, the synthesis method (2) is preferable because the synthesis is easy. For example, a vinyl monomer, which is a raw material for an amorphous vinyl resin, a polyvalent carboxylic acid and a polyhydric alcohol, which are raw materials for a crystalline polyester resin, and a bireactive monomer are mixed to prepare a polymerization initiator. Is added to form an amorphous vinyl resin segment by addition-polymerizing a vinyl monomer and a bireactive monomer, and then an esterification catalyst is added to carry out a polycondensation reaction to give a crystalline polyester resin segment. To form.

The bireactive monomer is a monomer that bonds the crystalline polyester resin and the amorphous resin, and has a hydroxy group, a carboxy group, an epoxy group, a first group capable of reacting with the crystalline polyester resin in the molecule. It is a monomer having a substituent such as a primary amino group or a secondary amino group, and an ethylenically unsaturated group capable of reacting with an amorphous resin. Among them, vinylcarboxylic acid having a hydroxy group or a carboxy group and an ethylenically unsaturated group is preferable.
As the bireactive monomer, for example, (meth)acrylic acid, fumaric acid, maleic acid and the like can be used, and esters of these hydroxyalkyl (having 1 to 3 carbon atoms) may be used. From the viewpoint of reactivity, acrylic acid, methacrylic acid or fumaric acid is preferable.

The amount of the bireactive monomer used is 100 parts by mass of the total amount of the monomers used for forming the amorphous resin segment, from the viewpoint of improving the low temperature fixing property, hot offset resistance and durability of the toner. On the other hand, it is preferably in the range of 1 to 10 parts by mass, more preferably in the range of 4 to 8 parts by mass.

The acid value of the crystalline polyester resin is preferably in the range of 10 to 40 mgKOH/g, more preferably 15 to 30 mgKOH/g.
When the acid value is 40 mgKOH/g or less, it is possible to prevent the crystalline polyester resin from being unevenly distributed in the surface layer of the toner particles due to the progress of hydrophilicity, and to suppress the deterioration of the charging property due to uneven distribution.

The acid value represents the mass of potassium hydroxide (KOH) necessary for neutralizing the acid contained in 1 g of the sample in mg unit. The acid value of the resin is measured by the following procedure according to JIS K0070-1966.

(Preparation of reagents)
A phenolphthalein solution is prepared by dissolving 1.0 g of phenolphthalein in 90 mL of ethyl alcohol (95% by volume) and adding ion-exchanged water to 100 mL. 7 g of JIS special grade potassium hydroxide is dissolved in 5 mL of ion-exchanged water, and ethyl alcohol (95% by volume) is added to make 1 liter. A potassium hydroxide solution is prepared by placing the solution in an alkali-resistant container for 3 days so that it does not come into contact with carbon dioxide, and then filtering it. Standardization follows the description of JIS K0070-1966.

(main exam)
2.0 g of the ground sample is precisely weighed in a 200 mL Erlenmeyer flask, 100 mL of a mixed solution of toluene/ethanol (2:1) is added, and the mixture is dissolved over 5 hours. Then, a few drops of the phenolphthalein solution prepared as an indicator are added, and titration is performed using the prepared potassium hydroxide solution. The end point of the titration is when the light red color of the indicator continues for about 30 seconds.
(Blank test)
The same operation as in the above main test is performed except that the sample is not used (that is, only the mixed solution of toluene/ethanol (2:1) is used).

The acid value is calculated by substituting the titration results of the main test and the blank test into the following formula (1).
Formula (1) A=[(B−C)×f×5.6]/S
A: Acid value (mgKOH/g)
B: Amount of potassium hydroxide solution added during blank test (mL)
C: Amount of potassium hydroxide solution added in this test (mL)
f: Factor of 0.1 mol/liter potassium hydroxide ethanol solution S: Mass of sample (g)

The crystalline polyester resin preferably has a weight average molecular weight (Mw) of 5,000 to 50,000 and a number average molecular weight (Mn) of 1,500 to 25,000. The weight average molecular weight and the number average molecular weight of the crystalline polyester resin can be measured by the above-mentioned GPC.

The melting point (T _m ) of the crystalline polyester resin is preferably in the range of 55 to 90° C., more preferably 70 to 85° C., from the viewpoint of obtaining sufficient low temperature fixability and excellent hot offset resistance. is there.
The melting point of the crystalline polyester resin can be controlled by the resin composition.

The melting point (T _m ) is the temperature at the peak top of an endothermic peak and can be measured by DSC.

<Colorant>
As the colorant contained in the toner particles of the present invention, known inorganic or organic colorants can be used. As the colorant, various organic and inorganic pigments, dyes and the like can be used in addition to carbon black and magnetic powder. Specifically, for magenta, C.I. I. Pigment Red 122 (manufactured by Clariant Japan) or the like can be used.
The amount of the colorant added is in the range of 1 to 30% by mass, preferably 2 to 20% by mass, based on the toner particles.

The toner particles further contain a release agent. In addition, a charge control agent, an external additive, and the like can be included as necessary.

〔Release agent〕
The release agent is not particularly limited, and various known waxes can be used. Examples of release agents that can be used include polyolefin waxes such as polyethylene wax and polypropylene wax, branched chain hydrocarbon waxes such as microcrystalline wax, long chain hydrocarbon waxes such as paraffin wax and sazol wax, and distearyl ketone. Such as dialkyl ketone wax, carnauba wax, montan wax, behenic acid behenate, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18- Examples thereof include ester waxes such as octadecanediol distearate, tristearyl trimellitate and distearyl maleate, and amide waxes such as ethylenediamine behenylamide and trimellitic acid tristearylamide.

The content of the release agent can be usually in the range of 1 to 30 parts by mass, and preferably in the range of 5 to 20 parts by mass with respect to 100 parts by mass of the binder resin. When the content of the release agent is within the above range, sufficient fixing separability can be obtained.
The content of the release agent in the toner particles is preferably in the range of 3 to 15% by mass.

(Charge control agent)
As the charge control agent, a known compound such as a nigrosine dye, a metal salt of naphthenic acid or a higher fatty acid, an alkoxylated amine, a quaternary ammonium salt, an azo metal complex, a salicylic acid metal salt can be used. By using the charge control agent, a toner having excellent charging characteristics can be obtained.
The content of the charge control agent can be usually in the range of 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the binder resin.

[External additive]
The toner particles can be used as a toner as they are, but may be treated with an external additive such as a fluidizing agent and a cleaning aid in order to improve fluidity, charging property, cleaning property and the like.

Examples of the external additive include fine particles of inorganic oxide such as fine particles of silica, fine particles of alumina and fine particles of titanium oxide, fine particles of inorganic stearate compound such as fine particles of aluminum stearate and fine particles of zinc stearate, strontium titanate, zinc titanate and the like. Examples thereof include inorganic titanate compound fine particles. These can be used alone or in combination of two or more.
It is preferable that these inorganic particles have been subjected to a gloss treatment with a silane coupling agent, a titanium coupling agent, a higher fatty acid, a silicone oil, or the like from the viewpoint of improving heat-resistant storage properties and environmental stability.

The addition amount of the external additive (when a plurality of external additives are used, the total addition amount) is preferably in the range of 0.05 to 5 parts by mass with respect to 100 parts by mass of the toner, and 0.1 More preferably, it is within the range of 3 parts by mass.

[Core/shell structure]
The toner particles can be used as a toner as they are, but in the present invention, the toner particles may have a core-shell structure including a shell layer covering the surface of the core. Thereby, the low temperature fixability can be further improved while maintaining the heat resistant storage property.

In the core-shell structure, the shell layer does not have to cover the entire surface of the core particle, and the core particle may be partially exposed. The cross section of the core-shell structure can be confirmed by a known observation means such as a transmission electron microscope (TEM) and a scanning probe microscope (SPM).

In the case of the core/shell structure, the characteristics such as glass transition point, melting point and hardness can be made different between the core particle and the shell layer, and the toner particle can be designed according to the purpose. For example, a binder resin, a colorant, and a release agent, etc., on the surface of the glass transition point (T _g) is relatively low core particles, glass transition point (T _g) aggregating the relatively high resin melting Can be applied to form a shell layer.

[Developer]
The toner for developing an electrostatic image of the present invention can be used as a magnetic or non-magnetic one-component developer, or may be mixed with a carrier and used as a two-component developer. When the toner is used as a two-component developer, magnetic particles made of conventionally known materials such as metals such as iron, ferrite and magnetite, alloys of those metals with metals such as aluminum and lead are used as the carrier. In particular, ferrite particles are preferable.

Further, as the carrier, a coated carrier in which the surface of magnetic particles is coated with a coating agent such as a resin, or a dispersion type carrier in which fine magnetic powder is dispersed in a binder resin may be used.
The volume-based median diameter (d ₅₀ ) of the carrier is preferably in the range of 20 to 100 μm, more preferably in the range of 25 to 80 μm.
The volume-based median diameter (d ₅₀ ) of the carrier can be measured, for example, by a laser diffraction particle size distribution analyzer HELOS (manufactured by SYMPATEC) equipped with a wet disperser.

<<Toner manufacturing method>>
The method for producing the toner according to the present invention is not particularly limited, and a known method can be adopted, but an emulsion polymerization aggregation method or an emulsion aggregation method can be suitably adopted.

The emulsion polymerization aggregation method preferably used in the method for producing a toner according to the present invention uses a dispersion liquid of binder resin fine particles (hereinafter also referred to as “binder resin fine particles”) produced by an emulsion polymerization method as a colorant. Fine particles (hereinafter, also referred to as “colorant fine particles”) dispersion and a release agent dispersion such as wax, and the toner particles are aggregated until a desired particle size is obtained. This is a method of producing toner particles by performing shape control by fusing.

The emulsion aggregation method preferably used as the method for producing the toner according to the present invention is a binder resin solution dissolved in a solvent, which is dropped into a poor solvent to obtain a resin particle dispersion liquid, and the resin particle dispersion liquid and the colorant dispersion liquid are used. And a release agent dispersion liquid such as wax are mixed and aggregated until a desired toner particle diameter is obtained, and then the shape is controlled by fusing the binder resin fine particles to produce toner particles. Is the way.
Either manufacturing method can be applied to the toner of the present invention.

An example of using the emulsion polymerization aggregation method as the method for producing the toner of the present invention is shown below.
(1) Step of preparing a dispersion liquid in which fine particles of a colorant are dispersed in an aqueous medium (2) Dispersion in which fine particles of a binder resin containing an internal additive, if necessary, are dispersed in the aqueous medium Step of preparing liquid (3) Step of preparing dispersion liquid of binder resin fine particles by emulsion polymerization (4) Mixing dispersion liquid of fine particles of colorant and dispersion liquid of binder resin fine particles to obtain colorant To form toner base particles by aggregating, associating, and fusing the fine particles and the binder resin fine particles with each other. (5) The toner base particles are filtered out from the dispersion system (aqueous medium) of the toner base particles, and a surfactant, etc. (6) Step of drying toner base particles (7) Step of adding external additive to toner base particles

In the case of producing a toner by the emulsion polymerization aggregation method, the binder resin fine particles obtained by the emulsion polymerization method may have a multilayer structure of two or more layers composed of binder resins having different compositions. As for the binder resin fine particles having different structures, for example, those having a two-layer structure, a dispersion liquid of resin particles is prepared by an emulsion polymerization treatment (first-stage polymerization) according to a conventional method, and a polymerization initiator is added to the dispersion liquid. It can be obtained by a method of adding a polymerizable monomer and subjecting this system to a polymerization treatment (second-stage polymerization).

Further, toner particles having a core/shell structure can be obtained by an emulsion polymerization aggregation method. Specifically, the toner particles having a core/shell structure are as follows: binder resin particles for core particles and particles of a colorant. To produce core particles by aggregating, associating, and fusing, and then adding the binder resin fine particles for the shell layer to the dispersion liquid of the core particles to aggregate the binder resin fine particles for the shell layer on the surface of the core particles. It can be obtained by forming a shell layer which is fused and covers the surface of the core particle.

An example of using a pulverization method as the method for producing the toner of the present invention is shown below.
(1) A step of mixing the binder resin, the colorant and, if necessary, an internal additive with a Henschel mixer or the like (2) A step of kneading the obtained mixture while heating it with an extrusion kneader or the like (3) Obtained A step in which the kneaded material is roughly pulverized by a hammer mill or the like and then further pulverized by a turbo mill or the like (4) The obtained pulverized material is subjected to fine powder classification using, for example, an air stream classifier utilizing the Coanda effect. Step of forming toner base particles (5) Step of adding an external additive to the toner base particles

[Particle size of toner particles]
The particle diameter of the toner particles constituting the toner of the present invention is, for example, preferably 4 to 10 μm in terms of volume-based median diameter, and more preferably 5 to 9 μm.

When the volume-based median diameter is within the above range, the transfer efficiency is increased, the halftone image quality is improved, and the image quality of fine lines and dots is improved.

The volume-based median diameter of toner particles is measured and calculated using a measuring device in which a computer system for data processing (manufactured by Beckman Coulter, Inc.) is connected to “Multisizer 3” (manufactured by Beckman Coulter, Inc.).

Specifically, 0.02 g of toner is added to 20 mL of a surfactant solution (for example, a surfactant solution obtained by diluting a neutral detergent containing a surfactant component 10 times with pure water for the purpose of dispersing toner particles). Then, ultrasonic dispersion treatment is performed for 1 minute to prepare a dispersion liquid of toner particles, and the dispersion liquid of the toner particles is put in "ISOTONII" (manufactured by Beckman Coulter, Inc.) in a sample stand. Pipette into the beaker until the indicated concentration on the measuring device is 5-10%. Here, by setting this concentration range, reproducible measurement values can be obtained. Then, in the measuring device, the number of particles to be measured was set to 25,000, the aperture diameter was set to 50 μm, and the frequency value was calculated by dividing the measurement range of 1 to 30 μm into 256. The particle size of% is the volume-based median diameter.

[Average circularity of toner particles]
The toner particles preferably have an average circularity in the range of 0.930 to 1.000, and more preferably in the range of 0.950 to 0.995, from the viewpoint of enhancing the stability of charging characteristics and the low temperature fixability. Is more preferable.
When the average circularity is within the above range, individual toner particles are less likely to be crushed. As a result, it is possible to suppress the contamination of the frictional charge imparting member and stabilize the chargeability of the toner, and it is possible to improve the image quality of the image formed.

The average circularity of the toner particles can be measured using FPIA-2100 (manufactured by Sysmex).
Specifically, the measurement sample (toner) is soaked in an aqueous solution containing a surfactant, and ultrasonically dispersed for 1 minute to disperse the sample. After that, FPIA-2100 (manufactured by Sysmex Corporation) is used to perform imaging in a measurement condition HPF (high-magnification imaging) mode at an appropriate density of 3000 to 10000 HPF detections. When the number of HPF detections is within the above range, reproducible measurement values can be obtained. The circularity of each toner particle is calculated from the photographed particle image according to the following formula (I), and the circularity of each toner particle is added and divided by the total number of toner particles to obtain the average circularity.
Formula (I)
Circularity = (perimeter of a circle having the same projected area as the particle image) / (perimeter of the particle projected image)

The embodiments to which the present invention can be applied are not limited to the above-described embodiments and can be appropriately modified without departing from the spirit of the present invention.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In the examples, “parts” or “%” are used, but unless otherwise specified, “parts by mass” or “% by mass” is shown.
The molecular weight, glass transition point (T _g ) and softening point were measured as follows.

[Measurement method of molecular weight]
The column was stabilized at 40° C. using gel permeation chromatography (GPC), and tetrahydrofuran (THF) as a solvent was flown through the column at a flow rate of 0.2 mL/min to adjust the sample concentration to 1 mg/mL. About 10 μL of a THF sample solution such as toner particles and resin was injected and measured. In measuring the molecular weight of the sample, a refractive index detector (RI detector) was used for detection, and the molecular weight distribution of the sample was calculated using a calibration curve prepared from a monodisperse polystyrene standard sample. As the standard polystyrene sample for measuring the calibration curve, the molecular weight of the standard polyester sample manufactured by Pressure Chemical Co., Ltd. is 6×10 ² , 2.1×10 ³ , 4×10 ³ , 1.75×10 ⁴ , 5.1×. Using 10 ⁴ , 1.1×10 ⁵ , 3.9×10 ⁵ , 8.6×10 ⁵ , 2×10 ⁶ , 4.48×10 ⁶ standard polystyrene samples were measured at 10 points, A calibration curve was created.

[Measuring method of melting point and glass transition temperature]
The melting point indicates the temperature at the top of the endothermic peak, and is measured by differential scanning calorimetry using a differential scanning calorimeter "DSC-7" (manufactured by Perkin Elmer) and a thermal analyzer controller "TAC7/DX" (manufactured by Perkin Elmer). DSC measurement was performed.
Specifically, 0.5 mg of the measurement sample is enclosed in an aluminum pan (KITNO.0219-0041), set in a sample holder of "DSC-7", and the temperature rise rate is measured at a measurement temperature of 0 to 200°C. The temperature of Heat-cool-Heat is controlled under the measurement conditions of 10° C./min and the cooling rate of 10° C./min. Analysis was performed based on the data in Heat. However, an empty aluminum pan was used to measure the reference.
The glass transition point temperature (T _g ) was 2nd. The data at Heat was acquired, and the intersection of the extension line of the baseline before the rise of the first endothermic peak and the tangent line showing the maximum slope from the rising portion of the first endothermic peak to the peak apex was taken as the glass transition point. The temperature (T _g ) was used.

[Measuring method of softening point (T _sp )]
First, in an environment of 20° C. and 50% RH, 1.1 g of a measurement sample was placed in a petri dish and flattened, and left for 12 hours or more, and then 3820 kg/cm by a molding machine “SSP-10A” (manufactured by Shimadzu Corporation). ^The sample was pressed with a force of ² for 30 seconds to prepare a cylindrical molded sample having a diameter of 1 cm. Then, this molded sample is heated under a load of 196 N (20 kgf), a starting temperature of 60° C., a preheating time of 300 seconds by a flow tester “CFT-500D” (manufactured by Shimadzu Corporation) in an environment of 24° C. and 50% RH. Extruded from the end of preheating using a piston with a diameter of 1 cm through a hole (1 mm diameter × 1 mm) in a cylindrical die at a speed of 6°C/min. The measured offset method temperature T _offset was used as the softening point of the measurement sample.

<<Synthesis Example of Toners 1-18>>
[Synthesis Example A of Amorphous Polyester Resin]
In a reaction vessel equipped with a stirrer, nitrogen introduction tube, temperature sensor, rectification column,
(Polycarboxylic acid)
Fumaric acid 4.2 parts by weight Terephthalic acid 78 parts by weight (polyhydric alcohol)
2,2-bis(4-hydroxyphenyl)propane propylene oxide 2 mol adduct 152 parts by mass 2,2-bis(4-hydroxyphenyl)propane ethylene oxide 2 mol adduct
After charging 48 parts by mass and raising the temperature of the reaction system to 190° C. over 1 hour and confirming that the inside of the reaction system was uniformly stirred, Ti(OBu) ₄ was added as a catalyst to the polycarboxylic acid. An amount of 0.006% by mass relative to the total amount was added, and the temperature of the reaction system was increased to 240°C over 6 hours from the same temperature while distilling off the produced water, and further maintained at 240°C. The amorphous polyester resin [A] was obtained by continuing the dehydration condensation reaction for 6 hours in this state to carry out the polymerization reaction. The obtained amorphous polyester resin [A] had a weight average molecular weight (Mw) of 2,700, a glass transition point (T _g ) of 63° C. and a softening point of 95° C. The molecular weight, glass transition point (T _g ) and softening point of the amorphous polyester resin [A] were measured as described above.

[Preparation Example A1 of Amorphous Polyester Resin Fine Particle Dispersion]
Methyl ethyl ketone and isopropyl alcohol were added to a reaction vessel equipped with an anchor blade for giving stirring power, and then the amorphous polyester resin [A] was coarsely crushed with a hammer mill and gradually added and stirred. Was dissolved or dispersed to obtain an oil phase. Then, an appropriate amount of dilute aqueous ammonia solution is added dropwise to the stirred oil phase, and further, this oil phase is added dropwise to ion-exchanged water for phase inversion emulsification, and then the solvent is removed under reduced pressure with an evaporator, An amorphous polyester resin fine particle dispersion is obtained, and ion-exchanged water is further added to this dispersion to adjust the solid content (amorphous polyester resin fine particles) to 20% by mass to obtain an amorphous A polyester resin fine particle dispersion [A1] was obtained.
The volume-based median diameter of the amorphous polyester resin fine particles in the obtained amorphous polyester resin fine particle dispersion [A1] was measured by an electrophoretic light scattering photometer "ELS-800" (manufactured by Otsuka Electronics Co., Ltd.). , 182 nm.

[Synthesis Example C of Crystalline Polyester Resin]
In a reaction vessel equipped with a stirrer, nitrogen introduction tube, temperature sensor, rectification column,
(Polycarboxylic acid)
200 parts by mass of 1,10-dodecanedioic acid (polyhydric alcohol)
After charging 140 parts by mass of 1,9-nonanediol and raising the temperature of the reaction system to 190° C. over 1 hour and confirming that the inside of the reaction system was uniformly stirred, Ti(OBu) ₄ was used as a catalyst. Was added in an amount of 0.006 mass% with respect to the total amount of polyvalent carboxylic acid, and the temperature of the reaction system was raised from the same temperature to 240° C. over 6 hours while distilling off the produced water. Then, the dehydration condensation reaction was continued for 6 hours while maintaining the temperature at 240° C. to carry out the polymerization reaction to obtain a crystalline polyester resin [C]. The obtained crystalline polyester resin [C] had a weight average molecular weight (Mw) of 2,900 and a melting point of 65°C. The molecular weight and melting point of the crystalline polyester resin [C] were measured as described above.

[Preparation Example C1 of Crystalline Polyester Resin Fine Particle Dispersion]
In Preparation Example A1 of the amorphous polyester resin fine particle dispersion liquid, the solid content (the crystalline polyester resin is the same as that of the crystalline polyester resin [C] except that the crystalline polyester resin [C] is used instead of the amorphous polyester resin [A]. Thus, a crystalline polyester resin fine particle dispersion liquid [C1] containing 20% by weight of fine particles was obtained. The volume-based median diameter of the crystalline polyester resin fine particles in the obtained crystalline polyester resin fine particle dispersion [C1] was measured by an electrophoretic light scattering photometer "ELS-800" (manufactured by Otsuka Electronics Co., Ltd.), and was 207 nm. Met.

[Preparation example S1 of vinyl resin fine particle dispersion]
An activator solution prepared by previously dissolving 2 parts by mass of an anionic activator (sodium dodecylbenzenesulfonate: DBS) in 740 parts by mass of ion-exchanged water in a separable flask equipped with a stirrer, a temperature sensor, a cooling tube, and a nitrogen introducing device. Was added, and the internal temperature paying part was heated to 80° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream.
On the other hand,
Styrene 295 parts by mass Acrylic acid 52 parts by mass 2-Ethylhexyl acrylate (2EHA) 40 parts by mass n-octyl mercaptan 0.46 parts by mass were mixed, and the mixture was moistened at 80° C. and dissolved to prepare a monomer solution. Here, the above two heated solutions were mixed and dispersed by a mechanical disperser having a circulation path to prepare emulsified particles having a uniform dispersed particle diameter. Then, a solution prepared by dissolving 3.3 parts by mass of a polymerization initiator (potassium persulfate: KPS) in 350 parts by mass of ion-exchanged water was added, and the mixture was heated and stirred at 80° C. for 3 hours to disperse the vinyl resin fine particles. A liquid was obtained, and ion-exchanged water was added to this dispersion to adjust the solid content (vinyl resin fine particles) to 20% by mass, whereby a vinyl resin fine particle dispersion [s1] was obtained. In the obtained dispersion liquid,
Fumaric acid 0.8 parts by mass Terephthalic acid 15 parts by mass 2,2-bis(4-hydroxyphenyl)propane propylene oxide 2 mol adduct
29 parts by mass 2,2-bis(4-hydroxyphenyl)propane ethylene oxide 2 mol adduct
A solution in which 9 parts by mass was stirred and dissolved at 80° C. for 1 hour was added, and the mixture was reacted for 12 hours under reflux to obtain a hybrid vinyl resin fine particle dispersion (vinyl resin fine particle dispersion [S1]).

The volume-based median diameter of the vinyl resin particles in the obtained vinyl resin particle dispersion [S1] was measured by an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.) and found to be 200 nm.
Further, the vinyl resin particle dispersion liquid [S1] was subjected to solid-liquid separation, and the softening point was measured to be 108°C.
The vinyl resin fine particle dispersion liquid [S1] was subjected to solid-liquid separation, and the tetrahydrofuran-soluble peak top molecular weight (Mp(s)) was measured to be 71,000.

[Preparation example of magenta colorant fine particle dispersion]
5 parts by mass of anionic surfactant "Neogen RK" (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was mixed and dissolved in 195 parts by mass of deionized water, and C.I. I. Pigment Red 122 (manufactured by Clariant Japan Co., Ltd.) is put therein and dispersed by a homogenizer “Ultra Turrax” (manufactured by IKA Co., Ltd.) for 10 minutes to obtain magenta coloring having a solid content (magenta colorant fine particles) of 20% by mass. A fine particle dispersion liquid [M] was obtained. The volume-based median diameter of the magenta colorant particles in the obtained magenta colorant particle dispersion [M] was measured by an electrophoretic light scattering photometer "ELS-800" (manufactured by Otsuka Electronics Co., Ltd.) and found to be 185 nm. It was

[Preparation Example of Release Agent Fine Particle Dispersion]
To 195 parts by mass of deionized water, 5 parts by mass of anionic surfactant "Neogen RK" (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 50 parts by mass of paraffin wax "FNP92" (melting point 91°C, manufactured by Nippon Seiro Co., Ltd.) were added. After heating to 60° C. and sufficiently dispersing with “Ultra Turrax T50” (manufactured by IKA Co.), the solid content (release agent fine particles) is 20% by mass by subjecting to dispersion treatment with a pressure discharge type Gorin homogenizer. Thus, a release agent fine particle dispersion [W] was obtained. The volume-based median diameter of the release agent fine particles in the obtained release agent fine particle dispersion liquid [W] was measured with an electrophoretic light scattering photometer “ELS-800” (manufactured by Otsuka Electronics Co., Ltd.) and found to be 170 nm. It was

[Toner Production Example 1]
Amorphous polyester resin fine particle dispersion liquid [A1]
1195 parts by mass Crystalline polyester resin fine particle dispersion [C1] 190 parts by mass Vinyl resin fine particle dispersion [S1] 125 parts by mass Magenta colorant fine particle dispersion [M] 200 parts by mass Release agent fine particle dispersion [W] 380 parts by mass Part Anionic surfactant "Neogen RK" (Daiichi Kogyo Seiyaku Co., Ltd.)
8 parts by mass Ion-exchanged water 300 parts by mass was placed in a reaction vessel equipped with a temperature sensor, a cooling pipe, a nitrogen introducing device, and a stirring device, and stirred. After adjusting the temperature in the container to 30° C., 1.0 mass% nitric acid aqueous solution was added to this solution to adjust the pH to 3.0.

Then, while dispersing with a homogenizer "Ultra Turrax T50" (manufactured by IKA), the temperature was raised to 47°C, and while measuring the particle size with "Multisizer 3" (manufactured by Beckman Coulter), When the volume-based median diameter (d ₅₀ ) reached 6.5 μm, a 5 mass% sodium hydroxide aqueous solution was added to adjust the pH to 9.0. Further, the mixture is heated and stirred at a liquid temperature of 90° C. for 3 hours, then cooled to 30° C. under the condition of 6° C./min, and hydrochloric acid is added to adjust the pH to 2.0. Particles were made.

The produced toner particles are subjected to solid-liquid separation, washing with 15 L of ion-exchanged water is repeated 4 times, and then dried with warm air of 40° C. to obtain toner [1X] of toner particles [1]. In the toner [1X], the volume-based median diameter (d ₅₀ ) of the toner particles [1] was 6.55 μm, and the average circularity was 0.964.
1% by mass of hydrophobic silica (number average primary particle size=12 nm, hydrophobicity=68) and hydrophobic titanium oxide (number average primary particle size=20 nm, hydrophobicity=63) were added to the obtained toner [1X]. 1% by mass was added and mixed with a "Henschel mixer" (manufactured by Nippon Coke Industry Co., Ltd.), and then subjected to an external additive treatment for removing coarse particles using a sieve having an opening of 45 μm. This is designated as toner [1].

[Production Example of Toners 2 to 18]
First, the vinyl resin fine particle dispersions [S2] to [S14] were prepared as follows.

<Preparation Examples S2 to S5, S8 to S11 of Vinyl Resin Fine Particle Dispersion>
Vinyl resin particle dispersions S2 to S5 and S8 to S11 were obtained in the same manner as in Preparation example S1 of vinyl resin particle dispersion, except that the amount of n-octyl mercaptan was changed to the amount shown in Table 1.

<Preparation example S6 of vinyl resin fine particle dispersion>
A vinyl resin fine particle dispersion S6 was obtained in the same manner as in Preparation Example S1 of vinyl resin fine particle dispersion, except that 2-ethylhexyl acrylate was changed to 2-carboxyethyl acrylate.

<Preparation example S7 of vinyl resin fine particle dispersion>
A vinyl resin fine particle dispersion S7 was obtained in the same manner as in Preparation Example S1 of vinyl resin fine particle dispersion, except that 2-ethylhexyl acrylate was changed to lauryl acrylate.

<Preparation example S12 of vinyl resin fine particle dispersion>
A vinyl resin fine particle dispersion S12 was obtained in the same manner as in Preparation Example S1 of vinyl resin fine particle dispersion, except that n-octyl mercaptan was not added.

<Preparation Example S13 of Vinyl Resin Fine Particle Dispersion>
A vinyl resin fine particle dispersion S13 was obtained in the same manner as in Preparation Example S4 of vinyl resin fine particle dispersion, except that 20 parts by mass of 1,6-hexanediol diacrylate was added as a crosslinking agent to the monomer solution.

<Preparation example S14 of vinyl resin fine particle dispersion liquid (non-hybrid vinyl resin fine particle dispersion liquid)>
An activator solution prepared by previously dissolving 2 parts by mass of an anionic activator (sodium dodecylbenzenesulfonate: DBS) in 740 parts by mass of ion-exchanged water in a separable flask equipped with a stirrer, a temperature sensor, a cooling tube, and a nitrogen introducing device. Was added, and the internal temperature paying part was heated to 80° C. while stirring at a stirring speed of 230 rpm under a nitrogen stream.
On the other hand,
Styrene 295 parts by mass Acrylic acid 52 parts by mass 2-Ethylhexyl acrylate (2EHA) 40 parts by mass n-octyl mercaptan 0.31 parts by mass were mixed, and the mixture was moistened at 80° C. and dissolved to prepare a monomer solution. Here, the above two heated solutions were mixed and dispersed by a mechanical disperser having a circulation path to prepare emulsified particles having a uniform dispersed particle diameter. Then, a solution prepared by dissolving 3.3 parts by mass of a polymerization initiator (potassium persulfate: KPS) in 350 parts by mass of ion-exchanged water was added, and the mixture was heated and stirred at 80° C. for 3 hours to disperse the vinyl resin fine particles. A liquid was obtained, and ion-exchanged water was added to this dispersion to adjust the solid content (vinyl resin fine particles) to 20% by mass to obtain a vinyl resin fine particle dispersion [S14].

<Physical Properties of Vinyl Resin Fine Particle Dispersion Liquids [S2] to [S14]>
The volume-based median diameter d ₅₀ of the vinyl resin fine particles, the softening point, and the peak top molecular weight (Mp(s)) of the tetrahydrofuran-soluble component of the vinyl resin fine particle dispersions [S2] to [S14] thus obtained were measured with the vinyl resin. The measurement was performed in the same manner as the fine particle dispersion [S1], and the results are summarized in Table 2.

<Toner Production Examples 2 to 8 and 10 to 17>
Toners [2] to [8], [10] to [17] are the same as in Toner Production Example 1 except that the type and amount of the vinyl resin fine particle dispersion liquid are changed to those shown in Table 3. Got

<Toner Production Example 9>
In Production Example 1 of Toner, the timing of addition of 125 parts by mass of the vinyl resin fine particle dispersion liquid [S1] that was initially added was set to a time point when the volume-based median diameter (d ₅₀ ) of the agglomerated particles reached 5.5 μm. Toner [9] was obtained in the same manner except that it was changed.

<Toner Production Example 18>
Toner [18] was obtained in the same manner as in Toner Production Example 1 except that the vinyl resin fine particle dispersion was not used.

Table 4 shows the configurations of the toners 1 to 18 produced as described above.
The amount of n-octyl mercaptan (NOM) was calculated as a ratio of the amount of NOM to the introduced mass of other monomers (styrene, acrylic acid, 2-ethylhexyl acrylate). That is,
NOM amount=NOM mass/(NOM mass+mass of other monomers)
Is.

≪Evaluation method≫
<Low temperature fixability evaluation>
As the image forming apparatus, a commercially available full-color multifunction machine "bizhub C754" (manufactured by Konica Minolta Co., Ltd.) is used which is modified so that the surface temperatures of the upper fixing belt and the lower fixing roller can be changed, and A4 (80 g/m ² basis weight) is used. ) A test of outputting a solid image with a toner adhesion amount of 11.3 g/m ² on plain paper at a nip width of 11.2 mm, a fixing time of 34 msec, a fixing pressure of 133 kPa, and a fixing temperature of 100 to 200° C. Was repeated in 5° C. increments.
The minimum fixing temperature at which the image stain due to the fixing offset was not visually confirmed was defined as the minimum fixing temperature. If the lowest fixing temperature is lower than 135° C., it is a good toner excellent in low-temperature fixing property, and if it is 135° C. or higher and lower than 150° C., there is no problem in practical use.
Further, if the temperature is 150° C. or higher and lower than 155° C., it can be used because it can be used by controlling the fixing process. There is a certain level.

<Glossiness evaluation>
The glossiness (GU) was evaluated by the same method as the above-mentioned low-temperature fixing property evaluation test, using the fixed image obtained at the temperature level of the upper fixing belt 20° C. higher than the temperature at which the low-temperature offset occurred. The glossiness of the fixed image was measured by using a gloss meter “GMX-203” (manufactured by Murakami Color Research Laboratory Co., Ltd.) according to JIS Z 8741, selecting a 75° measurement square type. The glossiness is a five-point average value at the center and four corners of the measured image.

(Evaluation criteria)
(Best): Less than 40 (Good): 40 or more and less than 45 (Fair): 45 or more and less than 50 (Not possible): 50 or more and less than 50 are regarded as the pass level.

As described above, according to the present invention, it is shown that an image in which gloss is suppressed while maintaining low-temperature fixability can be obtained in a toner using an amorphous polyester resin, a crystalline polyester resin and a vinyl resin.

Claims (7)

A toner for developing an electrostatic charge image, which comprises toner particles containing at least a binder resin, a release agent and a colorant,
The binder resin contains an amorphous polyester resin, a crystalline polyester resin, and a vinyl resin,
The amorphous polyester resin is an amorphous polyester resin composed of a polyvalent carboxylic acid and a polyhydric alcohol as a monomer,
The vinyl resin is a hybrid vinyl resin in which at least a vinyl polymerization segment and an amorphous polyester polymerization segment are bonded,
The content of the amorphous polyester resin in the binder resin is 50% by mass or more,
The weight average molecular weight (Mw(t)) of the component soluble in tetrahydrofuran (THF) measured by gel permeation chromatography (GPC) contained in the toner particles satisfies the following formula (1),
The vinyl resin has a peak top molecular weight (Mp(s)) satisfying the following formula (2),
And has a two-dimensional chain structure, and
A toner for developing an electrostatic charge image, wherein the vinyl resin has a structural unit derived from a (meth)acrylic acid alkyl ester-based monomer represented by the following structural formula (1).
Formula (1) Mw(t)<100000
Formula (2) 20000≦Mp(s)≦150,000
Structural formula _{(1) H 2 C = CR} 1 -COOR 2
[In the formula, R ₁ represents a hydrogen atom or a methyl group, and R ₂ represents an alkyl group having 6 to 22 carbon atoms. ] The electrostatic charge image developing toner according to claim 1, wherein the peak top molecular weight (Mp(s)) of the vinyl resin satisfies the following formula (3).
Formula (3) 30000≦Mp(s)≦100,000 The toner for developing an electrostatic charge image according to claim 1 or 2, wherein a weight average molecular weight Mw(s) of the vinyl resin satisfies the following formula (4).
Formula (4) 80,000≦Mw(s)≦200000 The electrostatic charge image according to any one of claims 1 to 3, wherein the content of the vinyl resin in the binder resin is within a range of 0.01 to 15% by mass. Toner for development. 5. The electrostatic image developing toner according to claim 1, wherein R ₂ in the structural formula (1) has a branched structure. The softening point T _sp vinyl resin, an electrostatic charge image developing toner according to any one of up to claims 1 to 5, characterized in that satisfies the following equation (5).
Formula (5) 100° C.≦T _sp ≦120° C. A method for producing an electrostatic charge image developing toner for producing the electrostatic charge image developing toner according to any one of claims 1 to 6.
The amorphous polyester resin, the crystalline polyester resin, and a dispersion of resin particles of a vinyl resin, and the fine particle dispersion of each of the release agent and the colorant are mixed and aggregated to control the shape of the toner particles. A method for producing a toner for developing an electrostatic charge image, which comprises the steps of: