JP7432368B2 - Method for manufacturing toner for developing electrostatic images - Google Patents

Description

The present invention relates to a method for producing an electrostatic image developing toner used for developing a latent image formed in electrophotography, electrostatic recording, electrostatic printing, or the like.

In the field of electrophotography, with the development of electrophotographic systems, there is a need to develop toners for electrophotography that are compatible with higher image quality and faster speeds. In response to higher image quality, a method to obtain toner with a narrow particle size distribution and small particle size is the aggregation-fusion method (emulsification), in which toner is obtained by agglomerating and fusing fine resin particles in an aqueous medium. So-called chemical toner is manufactured by a method (also called an agglomeration method or an agglomeration coalescence method).

Patent Document 1 discloses that an amine, a sulfonated polyester resin is used for the purpose of providing a process for economically preparing a toner useful in the formation of high-gloss images in a high yield without using a surfactant. A process for a toner is described that includes mixing an emulsion latex containing a colorant dispersion, heating the resulting mixture, and optionally cooling the resulting mixture. .

Japanese Patent Application Publication No. 11-258851

Patent Document 1 describes a toner containing colorant particles stabilized by a sulfonated polyester resin, and it is possible to form a toner in high yield without using a surfactant. However, the toner described in Patent Document 1 does not have sufficient coloring power, and there is also room for improvement regarding the charge amount distribution.
The present invention relates to a method for producing a toner for developing an electrostatic image, which provides a toner for developing an electrostatic image that has a high image density and a narrow charge amount distribution.

The present inventors have developed an amorphous polyester resin E containing a colorant and at least one of succinic acid and its anhydride substituted with a hydrocarbon group having 4 to 20 carbon atoms as a carboxylic acid component. It has been found that by using colorant particles that have a high image density and a narrow charge amount distribution, an electrostatic image developing toner can be obtained.
The present invention relates to the following [1].
[1] A method for producing a toner for developing an electrostatic image, comprising a step of aggregating and fusing resin particles and colorant particles in an aqueous medium, the colorant particles comprising a colorant and an amorphous polyester. The amorphous polyester resin E is a polycondensate of an alcohol component and a carboxylic acid component, and the carboxylic acid component is a hydrocarbon group having 4 or more and 20 or less carbon atoms. contains at least one of substituted succinic acid and its anhydride, and the mass ratio of the colorant to the amorphous polyester resin E in the colorant particles (colorant/amorphous polyester resin E) ) is 50/50 or more and 95/5 or less.

According to the present invention, there is provided a method for producing a toner for developing an electrostatic image, which provides a toner for developing an electrostatic image that has a high image density and a narrow charge amount distribution.

[Method for manufacturing toner for developing electrostatic image]
The method for producing an electrostatic image developing toner (hereinafter also simply referred to as "toner") of the present invention includes a step of aggregating and fusing resin particles and colorant particles in an aqueous medium.
The colorant particles contain a colorant and an amorphous polyester resin E, and the amorphous polyester resin E is a polycondensate of an alcohol component and a carboxylic acid component. The component contains at least one of succinic acid and its anhydride substituted with a hydrocarbon group having 4 or more and 20 or less carbon atoms. Further, the mass ratio of the colorant to the amorphous polyester resin E in the colorant particles (colorant/amorphous polyester resin E) is 50/50 or more and 95/5 or less.
By the above manufacturing method, an electrostatic image developing toner having a high image density and a narrow charge amount distribution can be obtained.

If the content of the colorant in the toner is the same, the more finely dispersed the colorant and the better the dispersion stability, the higher the image density can be obtained. In the present invention, since the hydrocarbon portion of the amorphous polyester resin E is adsorbed to the hydrophobic portion of the colorant, it is thought that the dispersion stability of the colorant particles is improved.
Furthermore, as the surface of the colorant particles is coated with amorphous polyester resin, the affinity with the binder resin is improved, the surface exposure of the colorant in the toner is suppressed, and the distribution of the amount of charge is narrowed. It is presumed that toner was obtained.
Note that the above mechanism regarding the effects of the present invention is a conjecture, and is not limited thereto.
In the following description, "excellent image density" means that the image density is high, and "excellent charge amount distribution" means that the charge amount distribution is narrow.

Definitions of various terms used in this specification are shown below.
In the specification, the carboxylic acid component of the polyester resin includes not only the compound, but also anhydrides that decompose during the reaction to produce carboxylic acids, and alkyl esters of each carboxylic acid (alkyl groups having 1 to 3 carbon atoms). (below) are also included.
Whether the resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is defined by the ratio of the softening point of the resin to the maximum endothermic peak temperature (softening point (°C)/maximum endothermic peak temperature (°C)) in the measurement method described in the Examples below. A crystalline resin is one having a crystallinity index of 0.6 or more and 1.4 or less. Amorphous resin is one with a crystallinity index of less than 0.6 or more than 1.4. The crystallinity index can be adjusted as appropriate by the types of raw material monomers, their ratios, and production conditions such as reaction temperature, reaction time, and cooling rate.
Regarding hydrocarbon groups, "(iso or tertiary)" and "(iso)" in parentheses mean both the presence and absence of these prefixes, and the absence of these prefixes. In this case, it indicates normal.
"(Meth)acrylic acid" means at least one selected from acrylic acid and methacrylic acid.
"(Meth)acrylate" means at least one selected from acrylate and methacrylate.
"(Meth)acryloyl group" means at least one kind selected from acryloyl group and methacryloyl group.
"Styrenic compound" means unsubstituted or substituted styrene.
"Backbone" means the relatively longest linking chain in the addition polymer.

A method for producing a toner according to an embodiment of the present invention includes, for example, a step of aggregating resin particles and colorant particles in an aqueous medium to obtain agglomerated particles (hereinafter also referred to as "Step 1"); and the agglomerated particles. A process of fusing in an aqueous medium (hereinafter also referred to as "Step 2")
including.

<Step 1>
In step 1, resin particles and colorant particles are aggregated to obtain aggregated particles. In step 1, in addition to the resin particles and colorant particles, other additives such as release agent particles may be aggregated.
(resin particles)
In step 1, the resin particles preferably contain at least amorphous resin A, and more preferably contain crystalline resin C.
The resin particles include resin particles X containing amorphous resin A, resin particles Y containing crystalline resin C, and resin particles XY containing amorphous resin A and crystalline resin C in the same particle. Although any of these may be used, it is preferable to use resin particles X containing amorphous resin A and resin particles Y containing crystalline resin C.
The resin particles preferably contain at least an amorphous resin (resin A) from the viewpoint of obtaining a toner with excellent image density and charge amount distribution, and the amorphous resin includes an amorphous polyester resin (resin A1). It is more preferable to contain.

[Amorphous polyester resin (resin A1)]
The amorphous polyester resin (resin A1) contains an amorphous polyester resin or an amorphous polyester segment that is a polycondensate of an alcohol component containing a diol compound and a carboxylic acid component containing a dicarboxylic acid compound.
Examples of the amorphous polyester resin include polyester resins and modified polyester resins. Examples of modified polyester resins include urethane-modified polyester resins, epoxy-modified polyester resins, and composite resins containing polyester resin segments and addition polymerized resin segments. Among these, polyester resins and composite resins are preferred, and polyester resins are more preferred.

Examples of the alcohol component include alkylene oxide adducts of aromatic diols, linear or branched aliphatic diols, alicyclic diols, and trivalent or higher polyhydric alcohols. Among these, alkylene oxide adducts of aromatic diols are preferred from the viewpoint of obtaining toners with excellent charge distribution and image density.
The alkylene oxide adduct of aromatic diol is preferably an alkylene oxide adduct of bisphenol A, more preferably of formula (I):

(In the formula, OR ¹ and R ² O are oxyalkylene groups, R ¹ and R ² are each independently an ethylene group or a propylene group, x and y represent the average number of added moles of alkylene oxide, and each and the value of the sum of x and y is 1 or more, preferably 1.5 or more, and 16 or less, preferably 8 or less, more preferably 4 or less). It is an oxide adduct.
Examples of the alkylene oxide adduct of bisphenol A include a propylene oxide adduct of bisphenol A [2,2-bis(4-hydroxyphenyl)propane] and an ethylene oxide adduct of bisphenol A. These may be used alone or in combination of two or more. Among these, propylene oxide adducts of bisphenol A are preferred.
The amount of the alkylene oxide adduct of bisphenol A in the alcohol component is preferably 70 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, and Preferably it is 100 mol%.

Examples of linear or branched aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butanediol. , 2,3-butanediol, 2,2-dimethyl-1,3-propanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1 , 12-dodecanediol.
Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane], alkylene oxides of hydrogenated bisphenol A having 2 to 4 carbon atoms (average number of added moles of 2 to 12 (below) adducts are mentioned.
Examples of the trihydric or higher polyhydric alcohol include glycerin, pentaerythritol, trimethylolpropane, and sorbitol.
These alcohol components may be used alone or in combination of two or more.

Examples of the carboxylic acid component include dicarboxylic acids and trivalent or higher polycarboxylic acids.
Examples of dicarboxylic acids include aromatic dicarboxylic acids, linear or branched aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Among these, at least one selected from aromatic dicarboxylic acids and linear or branched aliphatic dicarboxylic acids is preferred.
Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid and terephthalic acid are preferred, and terephthalic acid is more preferred.
The amount of aromatic dicarboxylic acid in the carboxylic acid component is preferably 20 mol% or more, more preferably 30 mol% or more, even more preferably 40 mol% or more, and preferably 90 mol% or less, more preferably It is 80 mol% or less, more preferably 75 mol% or less.

The number of carbon atoms in the linear or branched aliphatic dicarboxylic acid is preferably 2 or more, more preferably 3 or more, and preferably 30 or less, more preferably 20 or less.
Examples of linear or branched aliphatic dicarboxylic acids include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, and azelaic acid. , succinic acid substituted with a hydrocarbon group having 1 or more and 20 or less carbon atoms. Examples of the succinic acid substituted with a hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, and octenylsuccinic acid. Among these, fumaric acid, adipic acid, sebacic acid, and succinic acid substituted with the aforementioned alkyl group or alkenyl group are preferred, and succinic acid substituted with an alkyl group or alkenyl group is more preferred. The number of carbon atoms in the alkyl group or alkenyl group is 1 or more, preferably 4 or more, more preferably 6 or more, even more preferably 8 or more, even more preferably 10 or more, and preferably 20 or less, more preferably is 18 or less, more preferably 16 or less, even more preferably 14 or less.
In addition, when the amorphous polyester resin A1 contains succinic acid substituted with a hydrocarbon group having 1 to 20 carbon atoms as a carboxylic acid component, it has a higher affinity with the amorphous polyester resin E. As a result, the dispersibility of the colorant is improved, and as a result, a toner with excellent image density and charge amount distribution can be obtained.
The amount of linear or branched aliphatic dicarboxylic acid in the carboxylic acid component is preferably 1 mol% or more, more preferably 10 mol% or more, still more preferably 20 mol% or more, even more preferably 25 mol% or more. , and preferably 50 mol% or less, more preferably 45 mol% or less, still more preferably 40 mol% or less.

The polyvalent carboxylic acid having a valence of 3 or more is preferably a trivalent carboxylic acid, such as trimellitic acid or its anhydride.
When containing a trivalent or higher polyvalent carboxylic acid, the amount of the trivalent or higher polyvalent carboxylic acid is preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 8 mol% in the carboxylic acid component. The content is preferably at most 30 mol%, more preferably at most 20 mol%, even more preferably at most 15 mol%.
These carboxylic acid components may be used alone or in combination of two or more.

The equivalent ratio of the carboxy group of the carboxylic acid component to the hydroxyl group of the alcohol component [COOH group/OH group] is preferably 0.7 or more, more preferably 0.8 or more, and preferably 1.3 or less, more Preferably it is 1.2 or less.

<<Method for manufacturing resin A1>>
Resin A1 may be manufactured, for example, by a method including a step of performing a polycondensation reaction using an alcohol component and a carboxylic acid component.
In the step of performing the polycondensation reaction, if necessary, an esterification catalyst such as tin (II) di(2-ethylhexanoate), dibutyltin oxide, or titanium diisopropoxybis(triethanolaminate) is added to the alcohol component. 0.01 parts by mass or more and 5 parts by mass or less per 100 parts by mass of the total amount of the carboxylic acid component and the alcohol component; Polycondensation may be carried out using 0.001 parts by mass or more and 0.5 parts by mass or less based on 100 parts by mass of the total amount with the carboxylic acid component.
In addition, when using a monomer having an unsaturated bond such as fumaric acid in the polycondensation reaction, preferably 0.001 parts by mass based on 100 parts by mass of the total amount of the alcohol component and carboxylic acid component. A radical polymerization inhibitor may be used in an amount of 0.5 parts by mass or more. Examples of the radical polymerization inhibitor include 4-tert-butylcatechol.
The temperature of the polycondensation reaction is preferably 120°C or higher, more preferably 160°C or higher, even more preferably 180°C or higher, and preferably 260°C or lower, more preferably 250°C or lower.

≪Physical properties of resin A1≫
The softening point of the resin A1 is preferably 70°C or higher, more preferably 90°C or higher, even more preferably 100°C or higher, and preferably 140°C or lower, more preferably 130°C or lower, even more preferably 125°C or lower. It is.
The glass transition temperature of the resin A1 is preferably 30°C or higher, more preferably 40°C or higher, even more preferably 50°C or higher, and preferably 80°C or lower, more preferably 70°C or lower, even more preferably 60°C. It is as follows.

The acid value of the resin A1 is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, even more preferably 15 mgKOH/g or more, and preferably 40 mgKOH/g or less, more preferably 30 mgKOH/g or less, and Preferably it is 25 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of resin A1 can be adjusted as appropriate depending on the type and amount of raw material monomers used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate, and their values. is determined by the method described in the Examples.
In addition, when using a combination of two or more types of resin A1, it is preferable that the values of the softening point, glass transition temperature, and acid value obtained as a mixture thereof are each within the above-mentioned ranges.

In the present invention, the resin particles preferably contain a crystalline resin (resin C) from the viewpoint of obtaining a toner with excellent image density and charge amount distribution. As the crystalline resin, a crystalline polyester resin (resin C1) is preferable.
[Crystalline polyester resin (resin C1)]
The resin C1 is, for example, a polycondensate of an alcohol component and a carboxylic acid component.
The alcohol component preferably includes an α,ω-aliphatic diol.
The number of carbon atoms in the α,ω-aliphatic diol is preferably 2 or more, more preferably 4 or more, even more preferably 6 or more, and preferably 16 or less, more preferably 14 or less, even more preferably 12 or less. be.
Examples of the α,ω-aliphatic diol include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol Can be mentioned. Among these, 1,4-butanediol or 1,10-decanediol is preferred.

The amount of α,ω-aliphatic diol in the alcohol component is preferably 80 mol% or more, more preferably 85 mol% or more, even more preferably 90 mol% or more, even more preferably 95 mol% or more, and It is 100 mol% or less, more preferably 100 mol%.

The alcohol component may contain other alcohol components different from the α,ω-aliphatic diol. Other alcohol components include, for example, aliphatic diols other than α,ω-aliphatic diols such as 1,2-propylene glycol and neopentyl glycol; aromatic diols such as alkylene oxide adducts of bisphenol A; glycerin, pentyl glycol, etc. Examples include trihydric or higher alcohols such as erythritol and trimethylolpropane. These alcohol components may be used alone or in combination of two or more.

The carboxylic acid component preferably includes an aliphatic dicarboxylic acid.
The number of carbon atoms in the aliphatic dicarboxylic acid is preferably 4 or more, more preferably 8 or more, even more preferably 10 or more, and preferably 14 or less, more preferably 12 or less.
Examples of aliphatic dicarboxylic acids include fumaric acid, sebacic acid, dodecanedioic acid, and tetradecanedioic acid. Among these, sebacic acid, dodecanedioic acid, or tetradecanedioic acid is preferred, and sebacic acid is more preferred. These carboxylic acid components may be used alone or in combination of two or more.

The amount of aliphatic dicarboxylic acid in the carboxylic acid component is preferably 80 mol% or more, more preferably 85 mol% or more, even more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol%. % or less, more preferably 100 mol%.

The carboxylic acid component may contain another carboxylic acid component different from the aliphatic dicarboxylic acid. Other carboxylic acid components include, for example, aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid; and polycarboxylic acids of trivalent or higher valence. These carboxylic acid components may be used alone or in combination of two or more.

The equivalent ratio of the carboxy group of the carboxylic acid component to the hydroxyl group of the alcohol component (COOH group/OH group) is preferably 0.7 or more, more preferably 0.8 or more, and preferably 1.3 or less, more Preferably it is 1.2 or less.

≪Physical properties of resin C1≫
The softening point of the resin C1 is preferably 60°C or higher, more preferably 70°C or higher, even more preferably 80°C or higher, and preferably 150°C or lower, more preferably 120°C or lower, even more preferably 100°C or lower. It is.
The melting point of the resin C1 is preferably 50°C or higher, more preferably 60°C or higher, even more preferably 70°C or higher, and preferably 100°C or lower, more preferably 90°C or lower, even more preferably 80°C or lower. be.

The acid value of the resin C1 is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, and preferably 35 mgKOH/g or less, more preferably 30 mgKOH/g or less, and even more preferably 25 mgKOH/g or less. .

The softening point, melting point, and acid value of the resin C1 can be adjusted as appropriate depending on the types and ratios of raw material monomers, and production conditions such as reaction temperature, reaction time, and cooling rate. These values are determined by the method described in Examples below. In addition, when using a combination of two or more types of resin C1, it is preferable that the values of the softening point, melting point, and acid value obtained as a mixture thereof are each within the above-mentioned ranges.

The resin C1 is obtained, for example, by polycondensation of an alcohol component and a carboxylic acid component. As the conditions for polycondensation, for example, the conditions shown in the polycondensation for resin A1 described above can be applied.

The mass ratio [C/A] of resin C and resin A is preferably 1/99 or more, more preferably 3/97 or more, even more preferably 5/95 or more, and preferably 50/50 or less, It is more preferably 40/60 or less, still more preferably 30/70 or less, even more preferably 20/80 or less.

In the resin component of the toner, the total content of resin A and resin C is preferably 80% by mass or more, more preferably 90% by mass or more, and 100% by mass or less, preferably 98% by mass or less. It is.

[Method for manufacturing resin particles]
When the resin particles contain resin A and resin C, the resin particles contain resin A and resin C in the same or different resin particles. Here, in the following description, resin particles X containing resin A within the particles will be explained.
The aqueous medium is preferably one containing water as a main component, and from the viewpoint of improving the dispersion stability of the dispersion of resin particles and from the viewpoint of environmental friendliness, the water content in the aqueous medium is preferably 80% by mass. % or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and 100% by mass or less, still more preferably 100% by mass. As water, deionized water or distilled water is preferred. Components other than water that can be contained in the aqueous medium include, for example, alkyl alcohols having 1 to 5 carbon atoms; dialkyl ketones having 3 to 5 total carbon atoms such as acetone and methyl ethyl ketone; cyclic ethers such as tetrahydrofuran; Examples include soluble organic solvents. Among these, methyl ethyl ketone is preferred.

Although the dispersion can be performed using a known method, it is preferable to use a phase inversion emulsification method. Examples of the phase inversion emulsification method include a method in which an aqueous medium is added to an organic solvent solution of a resin or a molten resin to perform phase inversion emulsification.

The organic solvent used for phase inversion emulsification is not particularly limited as long as it dissolves the resin, but examples include methyl ethyl ketone.
It is preferable to add a neutralizing agent to the organic solvent solution. Examples of the neutralizing agent include basic substances. Examples of the basic substance include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; nitrogen-containing basic substances such as ammonia, trimethylamine, and diethanolamine.
The degree of neutralization of the resin contained in the resin particles It is 100 mol% or less, more preferably 80 mol% or less, even more preferably 70 mol% or less.
Note that the degree of neutralization of the resin contained in the resin particles can be determined by the following formula.
Degree of neutralization (mol%) = [{Added mass of neutralizing agent (g) / Equivalent weight of neutralizing agent} / [{Weighted average acid value of resin constituting resin particle X (mgKOH/g) x Resin particle X Mass of resin constituting (g)}/(56×1000)]×100

While stirring the organic solvent solution or the molten resin, an aqueous medium is gradually added to effect phase inversion.
The temperature of the organic solvent solution when adding the aqueous medium is preferably equal to or higher than the glass transition temperature of the amorphous resin A constituting the resin particles X, and more preferably 50°C from the viewpoint of improving the dispersion stability of the resin particles X. Above, the temperature is more preferably 60°C or higher, still more preferably 70°C or higher, and preferably 100°C or lower, more preferably 90°C or lower, and even more preferably 80°C or lower.
In addition, when manufacturing the resin particles Y, the temperature of the organic solvent solution when adding the aqueous medium is preferably 50°C or higher, more preferably 60°C or higher, and even more preferably 60°C or higher, from the viewpoint of improving dispersion stability. The temperature is 70°C or higher, and preferably 100°C or lower, more preferably 90°C or lower, and still more preferably 80°C or lower.

After the phase inversion emulsification, the organic solvent may be removed from the obtained dispersion by distillation or the like, if necessary. In this case, the residual amount of the organic solvent in the dispersion is preferably 1% by mass or less, more preferably 0.5% by mass or less, still more preferably substantially 0%.

The volume median particle diameter _D50 of the resin particles X in the dispersion is preferably 0.05 μm or more, more preferably 0.08 μm or more, and preferably is 1 μm or less, more preferably 0.5 μm or less, even more preferably 0.3 μm or less.
The CV value of the resin particles X in the dispersion is preferably 10% or more, more preferably 20% or more, and preferably 40% or less, more preferably is less than 30%.
The volume median particle diameter D ₅₀ and CV value are determined by the method described in Examples below.
Both the resin particles Y containing crystalline resin C and the resin particles XY containing amorphous resin A and crystalline resin C can be produced according to the method described above. The preferred ranges of the volume median particle diameter _D50 and CV value of the resin particles Y and resin particles XY are the same as the above-mentioned ranges.

(Colorant particles Z)
The colorant particles Z contain a colorant and an amorphous polyester resin E from the viewpoint of obtaining a toner with excellent image density and charge amount distribution. The colorant particles Z have, for example, an amorphous polyester resin E on the surface of the colorant, and preferably the surface of the colorant is coated with the amorphous polyester resin E.

[Colorant]
The coloring agent used in the present invention includes pigments and dyes, and pigments are preferred from the viewpoint of improving the image density of printed matter.
Examples of pigments include cyan pigments, yellow pigments, magenta pigments, and black pigments.
The cyan pigment is preferably a phthalocyanine pigment, and more preferably a copper phthalocyanine. The yellow pigment is preferably a monoazo pigment, an isoindoline pigment, or a benzimidazolone pigment, and the magenta pigment is preferably a soluble azo pigment such as a quinacridone pigment or a BONA lake pigment, or an insoluble azo pigment such as a naphthol AS pigment. The black pigment is preferably carbon black.
Examples of the dye include acridine dye, azo dye, benzoquinone dye, azine dye, anthraquinone dye, indigo dye, phthalocyanine dye, and aniline black dye. Colorants can be used alone or in combination of two or more.

Among these, naphthol-based azo pigments are preferred as the colorant because the amorphous polyester resin E has a high effect of improving image density and improving charge amount distribution. Examples of naphthol-based azo pigments include Pigment Red (hereinafter also referred to as "PR") 146, PR184, PR5, PR31, PR150, PR238, PR269, etc. Among these, toners with excellent image density and charge amount distribution are exemplified. From the viewpoint of obtaining the following, PR269, PR184, PR150, and PR238 are more preferable, and PR269 is still more preferable.

[Amorphous polyester resin E]
Amorphous polyester resin E is a polycondensate of an alcohol component and a carboxylic acid component, and the carboxylic acid component is , succinic acid substituted with a hydrocarbon group having 4 to 20 carbon atoms, and at least one of its anhydride.

Examples of the amorphous polyester resin E include polyester resins and modified polyester resins. Examples of modified polyester resins include urethane-modified polyester resins, epoxy-modified polyester resins, and composite resins containing polyester resin segments and addition polymerized resin segments. Among these, the polyester resin E is preferably a polyester resin or a composite resin, and more preferably a polyester resin.

The amorphous polyester resin E is, for example, a polycondensate of an alcohol component and a carboxylic acid component.
Examples of the alcohol component include alkylene oxide adducts of aromatic diols, linear or branched aliphatic diols, alicyclic diols, and trivalent or higher polyhydric alcohols.
The alkylene oxide adduct of aromatic diol is preferably of formula (I):

(In the formula, OR ¹ and R ² O are oxyalkylene groups, R ¹ and R ² are each independently an ethylene group or a propylene group, x and y represent the average number of added moles of alkylene oxide, and each and the value of the sum of x and y is 1 or more, preferably 1.5 or more, and 16 or less, preferably 8 or less, more preferably 4 or less). It is an oxide adduct.
Examples of alkylene oxide adducts of bisphenol A represented by formula (I) include propylene oxide adducts of 2,2-bis(4-hydroxyphenyl)propane and ethylene oxide of 2,2-bis(4-hydroxyphenyl)propane. Examples include additives. One or more of these may be used.
When an alkylene oxide adduct of bisphenol A represented by formula (I) is used as the alcohol component, its content is preferably 70 mol% or more, more preferably 80 mol% or more, and even more preferably is 90 mol% or more, more preferably 95 mol% or more, and is 100 mol% or less, still more preferably 100 mol%.

Examples of linear or branched aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butanediol. , 2,3-butanediol, 2,2-dimethyl-1,3-propanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1 , 12-dodecanediol, neopentyl glycol, and 1,4-butenediol. Among these, aliphatic diols having 3 or 4 carbon atoms having a hydroxyl group bonded to a secondary carbon atom are preferred. Specific examples include 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, and 2,3-butanediol. From the viewpoint of improving image density, 1,2-propanediol and 2,3-butanediol are preferred, and 1,2-propanediol is more preferred.
Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane], alkylene oxide adducts of hydrogenated bisphenol A having 2 to 4 carbon atoms (average number of added moles of 2 12 or less).
Examples of the trihydric or higher polyhydric alcohol include glycerin, pentaerythritol, trimethylolpropane, and sorbitol.
These alcohol components may be used alone or in combination of two or more.
When the alkylene oxide adduct of bisphenol A represented by formula (I) is not used as the alcohol component, the content of linear or branched aliphatic diol in the alcohol component is preferably 70 mol% or more, More preferably 80 mol% or more, still more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, still more preferably 100 mol%.

The carboxylic acid component contains at least one of succinic acid and its anhydride substituted with a hydrocarbon group having 4 to 20 carbon atoms. In addition to this, examples of the carboxylic acid component include aromatic dicarboxylic acid compounds, aliphatic dicarboxylic acid compounds, and trivalent or higher carboxylic acid compounds.
The number of carbon atoms in the hydrocarbon group having 4 to 20 carbon atoms in the succinic acid and its anhydride substituted with a hydrocarbon group having 4 to 20 carbon atoms is 4 or more from the viewpoint of imparting hydrophobicity, It is preferably 6 or more, more preferably 8 or more, even more preferably 9 or more, even more preferably 10 or more, and from the viewpoint of improving the affinity with the polyester resin, it is 20 or less, preferably 18 or less, more It is preferably 16 or less, more preferably 14 or less.
Further, the hydrocarbon group may be any of an alicyclic hydrocarbon group, an aliphatic hydrocarbon group, and an aromatic hydrocarbon group, but from the viewpoint of improving image density and charge amount distribution, an aliphatic hydrocarbon group is preferable. group, more preferably an alkenyl group or an alkyl group, still more preferably an alkenyl group.
Therefore, succinic acid substituted with a hydrocarbon group having 4 to 20 carbon atoms and its anhydride are succinic acid substituted with an alkenyl group having 4 to 20 carbon atoms, and an alkyl group having 4 to 20 carbon atoms. Preferably, it is at least one selected from substituted succinic acids and their anhydrides.

Examples of succinic acid and its anhydride substituted with a hydrocarbon group having 4 to 20 carbon atoms include butylsuccinic acid, pentylsuccinic acid, hexylsuccinic acid, heptylsuccinic acid, octylsuccinic acid, nonylsuccinic acid, decylsuccinic acid, undecyl Succinic acid, dodecyl succinic acid, tridecyl succinic acid, tetradecyl succinic acid, pentadecyl succinic acid, hexadecyl succinic acid, heptadecyl succinic acid, octadecyl succinic acid, nonadecyl succinic acid, icosyl succinic acid, butenyl succinic acid, pentenyl succinic acid, hexenyl Succinic acid, heptenyl succinic acid, octenyl succinic acid, nonenyl succinic acid, decenyl succinic acid, undecenyl succinic acid, dodecenyl succinic acid, tridecenyl succinic acid, tetradecenyl succinic acid, pentadecenyl succinic acid, hexadecenyl succinic acid , heptadecenyl succinic acid, octadecenyl succinic acid, nonadecenyl succinic acid, icosenyl succinic acid, and anhydrides thereof.
Among these, preferred are octenylsuccinic acid, decenylsuccinic acid, dodecenylsuccinic acid, tetradecenylsuccinic acid, and anhydrides thereof, more preferred are dodecenylsuccinic acid and its anhydrides, and still more preferred are dodecenylsuccinic anhydride.

The total content of succinic acid substituted with a hydrocarbon group having 4 to 20 carbon atoms and its anhydride in the carboxylic acid component is preferably 5 mol from the viewpoint of obtaining a toner with excellent image density and charge distribution. % or more, more preferably 7 mol% or more, still more preferably 10 mol% or more, still more preferably 20 mol% or more, even more preferably 30 mol% or more, and preferably 50 mol% or less, more preferably 45 mol% or more. It is not more than mol %, more preferably not more than 40 mol %.

In addition to the above-mentioned succinic acid substituted with a hydrocarbon group having 4 to 20 carbon atoms and its anhydride, the carboxylic acid component may contain an aromatic dicarboxylic acid compound from the viewpoint of further improving image density. preferable.
Examples of aromatic dicarboxylic acid compounds include phthalic acid, isophthalic acid, and terephthalic acid. Among these, from the viewpoint of low-temperature fixability, at least one selected from terephthalic acid and isophthalic acid is more preferred, and terephthalic acid is even more preferred.
The content of the aromatic dicarboxylic acid compound in the carboxylic acid component is preferably 50 mol% or more, more preferably 55 mol% or more, still more preferably 60 mol% or more, and 100 mol% or more. It is mol% or less, preferably 95 mol% or less, more preferably 93 mol% or less, still more preferably 90 mol% or less, still more preferably 80 mol% or less, and still more preferably 70 mol% or less.

Examples of aliphatic dicarboxylic acid compounds include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, and may be substituted with an aliphatic hydrocarbon group having 1 or more and 3 or less carbon atoms. Examples include aliphatic dicarboxylic acids such as succinic acid and adipic acid.
Among these, fumaric acid is preferred.
From the viewpoint of image density, the content of the aliphatic dicarboxylic acid compound in the carboxylic acid component is preferably 30 mol% or less, more preferably 20 mol% or less, even more preferably 10 mol% or less, and 0 mol% or more. and preferably 0 mol%.

Examples of trivalent or higher carboxylic acid compounds include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid. Among these, trimellitic acid and its anhydride are preferred.
The content of the trivalent or higher carboxylic acid compound in the carboxylic acid component is preferably 60 mol% or less, more preferably 30 mol% or less, and still more preferably 10 mol% or less, from the viewpoint of dispersibility of the mold release agent. , 0 mol% or more.
The alcohol component may contain a monovalent alcohol, and the carboxylic acid component may contain a monovalent carboxylic acid compound, as appropriate.

The ratio of the carboxy group of the carboxylic acid component to the hydroxyl group of the alcohol component [COOH group/OH group] is preferably 0.7 or more, more preferably 0.8 or more, and preferably 1.3 or less, more Preferably it is 1.2 or less.

<<Method for producing amorphous polyester resin E>>
In the present invention, the amorphous polyester resin E is produced, for example, by a method similar to the method for producing the amorphous polyester resin A1 described above.
The polycondensation of the alcohol component and the carboxylic acid component should be carried out, for example, in an inert gas atmosphere, if necessary, in the presence of an esterification catalyst, a polymerization inhibitor, etc., at a temperature of about 150°C or higher and 250°C or lower. Can be done.
Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin(II) di(2-ethylhexanoate), and titanium compounds such as titanium diisopropoxybis(triethanolaminate). Examples of esterification promoters that can be used with the esterification catalyst include gallic acid.
The amount of the esterification catalyst used is preferably 0.01 part by mass or more, more preferably 0.1 part by mass, based on 100 parts by mass of the alcohol component and carboxylic acid component, which are the raw materials for the amorphous polyester resin E. The amount is at least 1 part by mass, preferably 1 part by mass or less, and more preferably 0.6 part by mass or less.
The amount of the esterification promoter to be used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. It is 0.5 parts by mass or less, more preferably 0.1 parts by mass or less.
The amount of the polymerization inhibitor added is preferably 0.001 parts by mass or more and 0.5 parts by mass or less with respect to 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Examples of the radical polymerization inhibitor include 4-tert-butylcatechol.

≪Physical properties of amorphous polyester resin E≫
The softening point of the amorphous polyester resin E is preferably 80° C. or higher, more preferably 90° C. or higher, still more preferably 100° C. or higher, and even more preferably 105° C. or higher, from the viewpoint of increasing image density. From the viewpoint of further improving low-temperature fixability, the temperature is preferably 150°C or lower, more preferably 130°C or lower, and even more preferably 115°C or lower.

The glass transition temperature of the amorphous polyester resin E is preferably 40° C. or higher, more preferably 45° C. or higher, from the viewpoint of further improving storage stability, and preferably 45° C. or higher, from the viewpoint of further improving low-temperature fixability. is 75°C or lower, more preferably 65°C or lower, even more preferably 55°C or lower.

The acid value of the amorphous polyester resin E is preferably 10 mgKOH/g or more, more preferably 20 mgKOH/g or more, even more preferably 30 mgKOH/g or more, and preferably 60 mgKOH/g or less, more preferably 50 mgKOH/g. /g or less, more preferably 40mgKOH/g or less.
The softening point, glass transition temperature, and acid value of Resin E can be adjusted as appropriate depending on the type and amount of raw material monomers used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate, and their values. is determined by the method described in the Examples.
In addition, regarding the above physical properties of the amorphous polyester resin E, when the amorphous polyester resin E contains two or more types of amorphous polyester resin E, the weighted average value thereof must be within the above range. is preferred.

In the colorant particles, the mass ratio of the colorant to the amorphous polyester resin E is 50/50 or more, preferably 55/45 or more, from the viewpoint of obtaining a toner with excellent image density and charge amount distribution. Preferably it is 60/40 or more, more preferably 70/30 or more, and 95/5 or less, preferably 90/10 or less, more preferably 85/15 or less.

[Method for producing colorant particles Z]
The colorant particles Z are obtained, for example, by mixing a colorant and an amorphous polyester resin E.
There is no particular restriction on the method for producing the dispersion of colorant particles Z, and it may be possible to control the method using a known kneading machine, dispersion machine, etc. so that colorant particles with a desired volume median particle size D ₅₀ are obtained, but it is preferable. is obtained by mixing a colorant and a dispersion of amorphous polyester resin E using a homogenizer or a bead mill.

The method for producing colorant particles Z preferably includes:
Step a: After mixing the amorphous polyester resin E and an organic solvent, if necessary, a neutralizing agent is mixed and an aqueous medium is further mixed to obtain a dispersion of the amorphous polyester resin E. Step b: This method includes the steps of dispersing the dispersion obtained in Step a and a colorant to obtain a dispersion of colorant particles Z.
By including the organic solvent, the amorphous polyester resin E is dissolved in the organic solvent, and the amorphous polyester resin E is easily adsorbed to the colorant, thereby making it possible to further improve the dispersibility of the colorant.
Moreover, it is preferable that step b is a step of dispersing the dispersion obtained in step a and the colorant using a homogenizer or a bead mill.

In step a, it is preferable to first mix the amorphous polyester resin E and an organic solvent.
Examples of the organic solvent used here include alkyl alcohols having 1 to 3 carbon atoms, dialkyl ketones having 3 to 5 carbon atoms in total, and cyclic ethers. Among these, dialkyl ketones having a total carbon number of 3 or more and 5 or less are preferred, and methyl ethyl ketone is more preferred. When the amorphous polyester resin E is synthesized by a solution polymerization method, the solvent used in the polymerization may be used as is.

Examples of the neutralizing agent include basic substances. Examples of the basic substance include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; nitrogen-containing basic substances such as ammonia, trimethylamine, and diethanolamine. Among these, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide are preferred.
The degree of neutralization of the amorphous polyester resin E is preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 40 mol% or more, even more preferably 60 mol% or more, and even more preferably 70 mol%. and preferably 100 mol% or less, more preferably 95 mol% or less, and even more preferably 90 mol% or less.
Note that the degree of neutralization of the amorphous polyester resin E can be determined by the following formula.
Degree of neutralization (mol%) = [{Added mass of neutralizing agent (mg) / Equivalent weight of neutralizing agent} / {Acid value of amorphous polyester resin E (mgKOH/g) × Amorphous polyester resin Mass of E (g)/56}]×100
In step a, examples of the device used for mixing include a mixing and stirring device equipped with anchor blades, disper blades, and the like.
The temperature during mixing is preferably 0°C or higher, more preferably 10°C or higher, and preferably 40°C or lower, more preferably 30°C or lower, and even more preferably 25°C or lower.
The mixing time is preferably at least 1 minute, more preferably at least 3 minutes, even more preferably at least 5 minutes, and is preferably at most 10 hours, more preferably at most 1 hour, even more preferably at most 0.5 hour. be.

In step b, the mass ratio of the colorant and the amorphous polyester resin E [colorant/amorphous polyester resin E] is as described above.

In step b, it is preferable to add a colorant to the dispersion obtained in step a, mix it, and then perform a dispersion treatment. The apparatus used for mixing in step b and the temperature during mixing are the same as the apparatus used for mixing in step a and the temperature during mixing, and the preferred ranges are also the same. In step b, the mixing time after adding the colorant to the dispersion obtained in step a is preferably 0.5 hours or more, more preferably 0.8 hours or more, and preferably 30 hours or less, The time is more preferably 10 hours or less, and even more preferably 5 hours or less.
Equipment used in the dispersion treatment in step b includes, for example, kneading machines such as roll mills and kneaders, homogenizers such as microfluidizers (manufactured by Microfluidic), starbursts (manufactured by Sugino Machine Co., Ltd.), paint shakers, media such as bead mills, etc. An example is a type disperser. These devices may be used alone or in combination of two or more. Among these, bead mills and homogenizers are preferred from the viewpoint of reducing the particle size of the pigment, and homogenizers are more preferred from the viewpoint of further improving image density. Preferably, the homogenizer is a high pressure homogenizer.
When using a homogenizer, the processing pressure is preferably 60 MPa or more, more preferably 100 MPa or more, even more preferably 130 MPa or more, and preferably 270 MPa or less, more preferably 200 MPa or less, still more preferably 180 MPa or less.
Further, the number of passes is preferably 5 or more, more preferably 10 or more, and preferably 30 or less, more preferably 25 or less, still more preferably 20 or less.

It is preferable to remove the organic solvent from the obtained dispersion of colorant particles Z.
Further, it is preferable that the dispersion liquid of the colorant particles Z is filtered through a wire mesh or the like to remove coarse particles and the like. Furthermore, from the viewpoint of improving the productivity and storage stability of the dispersion, the amorphous polyester polymer E of the colorant particles may be crosslinked.
Further, various additives such as an organic solvent, a preservative, and an antifungal agent may be added to the dispersion liquid of the colorant particles Z.

In the dispersion of colorant particles Z, the colorant is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and preferably 50% by mass or less, more preferably The content is 40% by mass or less, more preferably 30% by mass or less, even more preferably 25% by mass or less, even more preferably 20% by mass or less.
The solid content concentration of the dispersion liquid of colorant particles Z is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and preferably 50% by mass or less, more preferably It is 40% by mass or less, more preferably 30% by mass or less.

From the viewpoint of improving image density, the volume median particle diameter D ₅₀ of the colorant particles Z is preferably 0.05 μm or more, more preferably 0.08 μm or more, even more preferably 0.1 μm or more, and preferably is 0.3 μm or less, more preferably 0.25 μm or less.
From the viewpoint of improving image density, the CV value of the colorant particles Z is preferably 10% or more, more preferably 20% or more, and preferably 40% or less, more preferably 35% or less.
The volume median particle diameter D ₅₀ and CV value of the colorant particles Z are measured by the method of the example.

The amount of colorant particles Z is preferably 3 parts by mass or more, more preferably 6 parts by mass or more, and still more preferably 10 parts by mass or more, from the viewpoint of further improving image density, based on 100 parts by mass of the resin particles. , and preferably 40 parts by mass or less, more preferably 30 parts by mass or less, still more preferably 20 parts by mass or less.
From the viewpoint of further improving image density, the content of the colorant is preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, and still more preferably 1 part by mass or more, based on 100 parts by mass of the binder resin. The amount is preferably 10 parts by weight or more, and preferably 40 parts by weight or less, more preferably 20 parts by weight or less, and even more preferably 15 parts by weight or less.

In the present invention, in step 1, colorant particles are aggregated in addition to at least resin particles. In addition to the above components, it is preferable to contain release agent particles.
That is, it is preferable that the mold release agent is added in the form of mold release agent particles and coagulated together with the resin particles and colorant particles.

(Release agent particles)
〔Release agent〕
The resin particles and colorant particles may be aggregated in the presence of a release agent.
As the mold release agent, for example, hydrocarbon waxes such as polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax, microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and Sasol wax, or their oxides; carnauba wax, Ester waxes such as montan wax or deoxidized wax thereof, fatty acid ester wax; fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts. These may be used alone or in combination of two or more.
Among these, as the mold release agent, hydrocarbon waxes and ester waxes are preferable, and hydrocarbon waxes are more preferable.

The melting point of the mold release agent is preferably 60°C or higher, more preferably 70°C or higher, and preferably 160°C or lower, more preferably 130°C or lower, even more preferably 100°C or lower.

The amount of the release agent in the toner is preferably 0.1% by mass or more, more preferably 1% by mass or more, even more preferably 5% by mass or more, and preferably 30% by mass or less, more preferably 25% by mass or more. The content is at most 20% by mass, more preferably at most 20% by mass, even more preferably at most 15% by mass.

≪Dispersion liquid of release agent particles≫
The release agent is preferably mixed with a resin particle dispersion and a colorant particle dispersion as a dispersion of release agent particles, and coagulated.
Although it is possible to obtain a dispersion of mold release agent particles using a surfactant, it is preferably obtained by mixing the mold release agent and resin particles P described below. By preparing the mold release agent particles using the mold release agent and the resin particles P, the mold release agent particles are stabilized by the resin particles P, and the mold release agent can be placed in an aqueous medium without using a surfactant. It becomes possible to disperse. It is thought that the dispersion of release agent particles has a structure in which many resin particles P are attached to the surface of the release agent particles.
The type and amount of the mold release agent to be added are the same as those for the mold release agent described above.

The resin constituting the resin particles P in which the release agent is dispersed is preferably a polyester resin, and from the viewpoint of improving the dispersibility of the release agent in an aqueous medium, it is a polycondensate of an alcohol component and a carboxylic acid component. It is more preferable to use a composite resin D having an addition polymerized resin segment that is an addition polymerized product of a polyester resin segment and a raw material monomer containing styrene.
The polyester resin segment is obtained by polycondensing the alcohol component and carboxylic acid component exemplified in the resin A1 above.
The addition polymerized resin segment is, for example, an addition polymerized product of raw material monomers containing a styrene compound.
Examples of the styrene compound include unsubstituted or substituted styrene. Examples of the substituent substituted on styrene include an alkyl group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group having 1 to 5 carbon atoms, a sulfonic acid group, or a salt thereof.
Examples of the styrenic compound include styrene, methylstyrene, α-methylstyrene, β-methylstyrene, tert-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid, or a salt thereof. Among these, styrene is preferred.
In the raw material monomer of the addition polymerized resin segment, the content of the styrene compound is preferably 50% by mass or more, more preferably 65% by mass or more, even more preferably 75% by mass or more, and 100% by mass or less. , preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less.

Examples of raw material monomers other than styrene compounds include (meth)acrylic acid esters such as alkyl (meth)acrylates, benzyl (meth)acrylates, and dimethylaminoethyl (meth)acrylate; ethylene, propylene, butadiene, etc. Olefins; halobinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether; vinylidene halides such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone. . Among these, (meth)acrylic esters are preferred, and alkyl (meth)acrylates are more preferred.
The number of carbon atoms in the alkyl group in the alkyl (meth)acrylate is preferably 1 or more, more preferably 4 or more, even more preferably 6 or more, and preferably 24 or less, more preferably 22 or less, even more preferably 20 It is as follows.
Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, (iso)propyl (meth)acrylate, (iso- or tertiary)butyl (meth)acrylate, and (meth)acrylate. ) (iso)amyl acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (iso)octyl (meth)acrylate, (iso)decyl (meth)acrylate, (meth)acrylic acid ( Examples include iso)dodecyl, (iso)palmityl (meth)acrylate, (iso)stearyl (meth)acrylate, (iso)behenyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate or (meth)acrylate. Stearyl acrylate is preferred, stearyl (meth)acrylate is more preferred, and stearyl methacrylate is even more preferred.
Note that "(iso or tertiary)" and "(iso)" mean both the presence and absence of these prefixes, and the absence of these prefixes indicates normal. Moreover, "(meth)acrylic acid" indicates acrylic acid or methacrylic acid.

The content of (meth)acrylic acid ester in the raw material monomer of the addition polymerized resin segment is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and preferably 50% by mass or more. It is at most 35% by mass, more preferably at most 35% by mass, even more preferably at most 25% by mass.
The total amount of the styrene compound and (meth)acrylic acid ester in the raw material monomers of the addition polymerized resin segment is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and even more preferably is 100% by mass.

The composite resin D preferably has a structural unit derived from a bireactive monomer bonded to the polyester resin segment and the addition polymerized resin segment via a covalent bond.
The term "constituent unit derived from a bireactive monomer" means a unit in which a functional group or an addition polymerizable group of a bireactive monomer has reacted.
Examples of the addition polymerizable group include a carbon-carbon unsaturated bond (ethylenic unsaturated bond).
Examples of bireactive monomers include addition-polymerizable monomers having at least one functional group selected from a hydroxyl group, a carboxy group, an epoxy group, a primary amino group, and a secondary amino group in the molecule. . Among these, from the viewpoint of reactivity, addition-polymerizable monomers having at least one functional group selected from a hydroxyl group and a carboxy group are preferred, and addition-polymerizable monomers having a carboxyl group are more preferred.
Examples of the addition polymerizable monomer having a carboxyl group include acrylic acid, methacrylic acid, fumaric acid, and maleic acid. Among these, acrylic acid and methacrylic acid are preferred, and acrylic acid is more preferred, from the viewpoint of reactivity in both polycondensation reactions and addition polymerization reactions.
When the bireactive monomer is an addition polymerizable monomer having a carboxyl group, the amount of the structural unit derived from the bireactive monomer is preferably 1 mol per 100 mol parts of the alcohol component of the polyester resin segment of composite resin D. part or more, more preferably 5 molar parts or more, still more preferably 8 molar parts or more, and preferably 30 molar parts or less, more preferably 25 molar parts or less, still more preferably 20 molar parts or less.

The content of the polyester resin segment in the composite resin D is preferably 35% by mass or more, more preferably 45% by mass or more, even more preferably 50% by mass or more, and preferably 90% by mass or less, more preferably It is 85% by mass or less, more preferably 75% by mass or less.

The content of the addition polymerized resin segment in the composite resin D is preferably 5% by mass or more, more preferably 15% by mass or more, even more preferably 25% by mass or more, and preferably 60% by mass or less, more preferably is 55% by mass or less, more preferably 45% by mass or less.

The content of the structural unit derived from the bireactive monomer in the composite resin D is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 0.8% by mass or more, and , preferably 10% by mass or less, more preferably 7% by mass or less, still more preferably 4% by mass or less.

The total amount of structural units derived from the polyester resin segment, the addition polymerized resin segment, and the bireactive monomer in the composite resin D is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more. The content is 100% by mass or less, and more preferably 100% by mass.

The above amount is calculated based on the ratio of the amounts of the raw material monomer, bireactive monomer, and radical polymerization initiator for the polyester resin segment, addition polymerization resin segment, and excludes the amount of dehydration due to polycondensation in the polyester resin segment, etc. In addition, when a radical polymerization initiator is used, the mass of the radical polymerization initiator is calculated by including it in the addition polymerization resin segment.

The composite resin D may be produced, for example, by a method including a step A in which an alcohol component and a carboxylic acid component are polycondensed, and a step B in which a raw material monomer of an addition polymerized resin segment and a bireactive monomer are subjected to addition polymerization.
Process B may be performed after process A, process A may be performed after process B, or process A and process B may be performed simultaneously.
In Step A, a part of the carboxylic acid component is subjected to a polycondensation reaction, and then after carrying out Step B, the remaining part of the carboxylic acid component is added to the polymerization system to perform the polycondensation reaction of Step A and the bireactive monomer or both. A method in which a polycondensation reaction with a carboxy group contained in a component derived from a reactive monomer is further advanced is preferred.

In step A, if necessary, an esterification catalyst such as tin(II) di(2-ethylhexanoate), dibutyltin oxide, or titanium diisopropoxybis(triethanolaminate) is added to the alcohol component and the carboxylic acid component. 0.01 parts by mass or more and 5 parts by mass or less per 100 parts by mass of the total amount of Polycondensation may be carried out using 0.001 parts by mass or more and 0.5 parts by mass or less based on 100 parts by mass of the total amount.
In addition, when using a monomer having an unsaturated bond such as fumaric acid in polycondensation, preferably 0.001 parts by mass or more based on 100 parts by mass of the total amount of alcohol component and carboxylic acid component, if necessary. A radical polymerization inhibitor of 0.5 parts by mass or less may be used. Examples of the radical polymerization inhibitor include 4-tert-butylcatechol.
The temperature of the polycondensation reaction is preferably 120°C or higher, more preferably 160°C or higher, even more preferably 180°C or higher, and preferably 250°C or lower, more preferably 240°C or lower. Note that the polycondensation may be performed in an inert gas atmosphere.

Examples of the radical polymerization initiator for addition polymerization in step B include peroxides such as dibutyl peroxide, persulfates such as sodium persulfate, and 2,2'-azobis(2,4-dimethylvaleronitrile). Examples include azo compounds.
The amount of the radical polymerization initiator used is preferably 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the raw material monomer of the addition polymerization resin segment.
The temperature of addition polymerization is preferably 110°C or higher, more preferably 130°C or higher, and preferably 230°C or lower, more preferably 220°C or lower, even more preferably 210°C or lower.

The softening point of the composite resin D is preferably 70°C or higher, more preferably 80°C or higher, and preferably 140°C or lower, more preferably 120°C or lower, and still more preferably 100°C or lower.
The glass transition temperature of the composite resin D is preferably 30°C or higher, more preferably 40°C or higher, and preferably 80°C or lower, more preferably 60°C or lower.
The acid value of the composite resin D is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, even more preferably 15 mgKOH/g, even more preferably 20 mgKOH/g or more, and preferably 40 mgKOH/g or less, and more preferably 40 mgKOH/g or more. Preferably it is 35 mgKOH/g or less, more preferably 30 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of composite resin D can be adjusted as appropriate depending on the type and amount of raw material monomers used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate. The value is determined by the method described in the Examples.

The dispersion of resin particles P can be obtained, for example, by the above-mentioned phase inversion emulsification method.
The volume median particle diameter D ₅₀ of the resin particles P is preferably 0.01 μm or more, more preferably 0.03 μm or more, and preferably 0.3 μm or less, from the viewpoint of dispersion stability of the mold release agent particles. , more preferably 0.2 μm or less.
From the viewpoint of dispersion stability of the release agent particles, the CV value of the resin particles P is preferably 10% or more, more preferably 20% or more, and preferably 40% or less, more preferably 35% or less, More preferably, it is 30% or less.

The release agent particle dispersion can be prepared, for example, by combining a dispersion of the release agent and resin particles P with an aqueous medium as necessary, at a temperature equal to or higher than the melting point of the release agent, using a homogenizer, high-pressure disperser, or ultrasonic disperser. It can be obtained by dispersing using a dispersing machine with strong shearing force such as
The heating temperature during dispersion is preferably higher than the melting point of the mold release agent and 80°C or higher, more preferably 85°C or higher, even more preferably 90°C or higher, and preferably softens the resin contained in the resin particles P. The temperature is less than 10°C higher than the point and 100°C or less, more preferably 98°C or less, even more preferably 95°C or less.

The amount of resin particles P is preferably 5 parts by mass or more, more preferably 8 parts by mass or more, still more preferably 10 parts by mass or more, still more preferably 20 parts by mass or more, and even more preferably is 30 parts by mass or more, and preferably 70 parts by mass or less, more preferably 60 parts by mass or less, even more preferably 50 parts by mass or less.

The volume median particle diameter D ₅₀ of the release agent particles is preferably 0.05 μm or more, more preferably 0.2 μm or more, and still more preferably 0.3 μm or more, from the viewpoint of obtaining uniform aggregated particles. Preferably it is 1 μm or less, more preferably 0.8 μm or less, even more preferably 0.6 μm or less.
The CV value of the release agent particles is preferably 10% or more, more preferably 20% or more, and preferably 40% or less, more preferably 35% or less, and still more preferably 30% or less.
The volume median particle diameter _D50 and CV value of the release agent particles are measured by the methods described in Examples.

The aggregation of the resin particles and colorant particles may be carried out in the presence of other additives in addition to the release agent.
Other additives include, for example, charge control agents, magnetic powders, fluidity improvers, conductivity modifiers, reinforcing fillers such as fibrous substances, antioxidants, anti-aging agents, and cleaning performance improvers. .

[Surfactant]
In step 1, the dispersion liquid of each particle is mixed to prepare a mixed dispersion liquid, and the dispersion stability of optional components such as resin particles, colorant particles, and release agent particles added as necessary is improved. From the viewpoint of making the reaction easier, it may be carried out in the presence of a surfactant. Examples of the surfactant include anionic surfactants such as alkylbenzene sulfonates and alkyl ether sulfates; nonionic surfactants such as polyoxyethylene alkyl ethers and polyoxyethylene alkenyl ethers.
When using a surfactant, the amount used is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more for each type of surfactant, based on 100 parts by mass of the resin particles. The amount is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less.

The above-mentioned dispersion of resin particles, dispersion of colorant particles, and optional components are mixed by a conventional method. It is preferable to add a flocculant to the mixed dispersion obtained by the mixing from the viewpoint of efficiently performing flocculation.

[Flocculant]
Examples of the flocculant include cationic surfactants such as quaternary salts, organic flocculants such as polyethyleneimine, and inorganic flocculants. Examples of inorganic flocculants include inorganic metal salts such as sodium sulfate, sodium nitrate, sodium chloride, calcium chloride, and calcium nitrate; inorganic ammonium salts such as ammonium sulfate, ammonium chloride, and ammonium nitrate; and divalent or higher metal complexes. .
From the viewpoint of improving cohesiveness and obtaining uniform agglomerated particles, inorganic flocculants with a valence of 1 or more and 5 or less are preferable, inorganic metal salts and inorganic ammonium salts with a valence of 1 or more and 2 or less are more preferable, and inorganic ammonium salts are more preferable. More preferred is ammonium sulfate.

Using an aggregating agent, for example, in a mixed dispersion containing resin particles and colorant particles at a temperature of 0°C or more and 40°C or less, 5 parts by mass or more and 60 parts by mass or less are aggregated based on 100 parts by mass of the total amount of resin in the resin particles. The resin particles and colorant particles are aggregated in an aqueous medium to obtain aggregated particles. Furthermore, from the viewpoint of promoting aggregation, it is preferable to raise the temperature of the dispersion after adding the flocculant.

Aggregation may be stopped when the aggregated particles have grown to an appropriate particle size as toner particles.
Examples of methods for stopping aggregation include a method of cooling the dispersion, a method of adding an aggregation stopper, and a method of diluting the dispersion. From the viewpoint of reliably preventing unnecessary aggregation, it is preferable to add an aggregation stopper to stop aggregation.

[Aggregation stopper]
As the aggregation stopper, surfactants are preferred, and anionic surfactants are more preferred. Examples of the anionic surfactant include alkylbenzene sulfonates, alkyl sulfates, alkyl ether sulfates, polyoxyalkylene alkyl ether sulfates, and the like. These may be used alone or in combination of two or more. The flocculation stopper may be added in the form of an aqueous solution.
From the viewpoint of reliably preventing unnecessary agglomeration, the amount of the aggregation stopper added is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and even more preferably The content is 10 parts by mass or more, and from the viewpoint of reducing residue in the toner, the content is preferably 60 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less.

The volume median particle diameter _D50 of the aggregated particles is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less, and still more preferably 6 μm or less. be. The volume median particle diameter D ₅₀ of the aggregated particles is determined by the method described in Examples below.

In the present invention, after step 1 and before step 2, resin particles may include a step (step 1') of adhering ' to obtain aggregated particles 2.
Here, as the amorphous polyester resin used for the resin particles X', the above-mentioned amorphous polyester resin (resin A1) is exemplified. The resin particles X' are obtained by the same method as the resin particles X described above.
Further, when the toner manufacturing method has step 1', it is preferable to stop the aggregation when the agglomerated particles 2 have grown to an appropriate particle size as toner particles in step 1', and use the above-mentioned aggregation stopper. A method in which the agglomeration is stopped by addition is preferred.

<Step 2>
In step 2, for example, the aggregated particles are fused in an aqueous medium.
By fusion, each particle contained in the aggregated particles is fused together to obtain fused particles.
The volume median particle diameter D ₅₀ of the fused particles obtained by fusion is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less. , more preferably 6 μm or less.

The circularity of the fused particles obtained by fusion is preferably 0.955 or more, more preferably 0.960 or more, and preferably 0.990 or less, more preferably 0.985 or less, even more preferably It is 0.980 or less.
It is preferable that the fusion be completed after reaching the above-mentioned preferred circularity.
Circularity is measured by the method described in Examples.

<Post-processing process>
A post-treatment step may be performed after step 2, and toner particles are obtained by isolating the fused particles. Since the fused particles obtained in step 2 are present in an aqueous medium, it is preferable to perform solid-liquid separation first. A suction filtration method or the like is preferably used for solid-liquid separation.
It is preferable to perform washing after solid-liquid separation. At this time, since it is preferable to also remove the added surfactant, it is preferable to wash with an aqueous medium at a temperature below the clouding point of the surfactant. It is preferable to perform washing multiple times.
Next, drying is preferably performed. Examples of the drying method include a vacuum low temperature drying method, a vibratory fluidized drying method, a spray drying method, a freeze drying method, and a flash jet method.

[Toner particles]
The volume median particle diameter _D50 of the toner particles is preferably 2 μm or more, more preferably 3 μm or more, and even more preferably 4 μm or more, from the viewpoint of obtaining high-quality images and improving the cleaning performance of the toner. The thickness is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 6 μm or less.

The CV value of the toner particles is preferably 12% or more, more preferably 16% or more, even more preferably 20% or more from the viewpoint of improving toner productivity, and from the viewpoint of obtaining high-quality images, Preferably it is 35% or less, more preferably 30% or less.
The volume median particle diameter _D50 and CV value of the toner particles can be measured by the method described in Examples.

[Toner for developing electrostatic images]
The toner includes toner particles.
Although the toner particles can be used as they are, it is preferable to add a fluidizing agent or the like to the surface of the toner particles as an external additive before using the toner.

[External additive]
Examples of external additives include fine particles of inorganic materials such as hydrophobic silica, titanium oxide, alumina, cerium oxide, and carbon black, and fine particles of polymers such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic silica is preferred. One type of external additive may be used alone, or two or more types may be used. Furthermore, two or more types of hydrophobic silica having different particle sizes may be used.
When surface-treating toner particles using an external additive, the amount of the external additive added is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and even more preferably The amount is 3 parts by weight or more, and preferably 5 parts by weight or less, more preferably 4.5 parts by weight or less, and still more preferably 4 parts by weight or less.

Toner is used for electrostatic image development in electrophotographic printing. The toner can be used, for example, as a one-component developer, or mixed with a carrier and used as a two-component developer.

EXAMPLES The present invention will be specifically explained below with reference to Examples, but the present invention is not limited to these Examples in any way. Each property value was measured and evaluated by the following method.
In addition, in the description such as "alkylene oxide (X)", the numerical value X in parentheses means the average number of moles of alkylene oxide added.

[Measuring method]
[Acid value of resin]
The acid value of the resin was measured according to the neutralization titration method described in JIS K 0070:1992. However, the measurement solvent was chloroform.

[Softening point, crystallinity index, melting point and glass transition temperature of resin]
(1) Softening point Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), 1 g of sample was heated at a temperature increase rate of 6°C/min while applying a load of 1.96 MPa with a plunger. It was extruded from a nozzle with a diameter of 1 mm and a length of 1 mm. The fall of the plunger of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was defined as the softening point.
(2) Crystallinity index Using a differential scanning calorimeter “Q100” (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan and cooled to 0°C at a cooling rate of 10°C/min. did. Next, the sample was allowed to stand still for 1 minute, and then the temperature was raised to 180°C at a heating rate of 10°C/min, and the amount of heat was measured. Among the observed endothermic peaks, the temperature of the peak with the largest peak area is defined as the maximum endothermic peak temperature (1), and then (softening point (℃)) / (maximum endothermic peak temperature (1) (℃)), The crystallinity index was determined.
(3) Melting point and glass transition temperature Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and the temperature was measured. The temperature was cooled from 10° C. to 0° C. at a cooling rate of 10° C./min. Next, the sample was heated at a heating rate of 10° C./min, and the amount of heat was measured. Among the endothermic peaks observed, the temperature of the peak with the largest peak area was defined as the maximum endothermic peak temperature (2). In the case of crystalline resins, the peak temperature was taken as the melting point.
In addition, when a peak is observed in the case of an amorphous resin, the temperature of the peak is measured, and when a step is observed without a peak, the tangent line indicating the maximum slope of the curve of the step portion and the temperature of the step. The temperature at the intersection with the extension line of the baseline on the low temperature side was defined as the glass transition temperature.

[Melting point of mold release agent]
Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and then cooled at a cooling rate of 10°C/min from 200°C. The mixture was cooled to 0°C. Next, the sample was heated at a heating rate of 10°C/min, the amount of heat was measured, and the maximum peak temperature of endotherm was taken as the melting point.

[Volume median particle diameter _D50 and CV value of resin particles, colorant particles, and mold release agent particles]
(1) Measuring device: Laser diffraction particle size measuring machine “LA-920” (manufactured by Horiba, Ltd.)
(2) Measurement conditions: A sample dispersion was placed in a measurement cell, distilled water was added, and the volume median particle diameter D ₅₀ and volume average particle diameter D _v were measured at a concentration where the absorbance was within an appropriate range. Further, the CV value was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution/volume average particle diameter _Dv ) x 100

[Solid content concentration of resin particle dispersion, colorant particle dispersion, and release agent particle dispersion]
Using an infrared moisture meter "FD-230" (manufactured by Kett Science Institute Co., Ltd.), 5 g of the measurement sample was dried at a drying temperature of 150°C, measurement mode 96 (monitoring time 2.5 minutes, moisture content fluctuation range 0.05%). ), the water content (mass%) was measured. The solid content concentration was calculated according to the following formula.
Solid content concentration (mass%) = 100 - water (mass%)

[Moisture content of toner particles]
Using an infrared moisture meter "FD-230" (manufactured by Kett Science Institute Co., Ltd.), 5 g of toner particles were dried at a drying temperature of 150°C, measurement mode 96 (monitoring time 2.5 minutes, moisture content fluctuation range 0.05%). ), the water content (mass%) was measured.

[Volume median particle diameter D ₅₀ of aggregated particles]
The volume median particle diameter _D50 of the aggregated particles was measured as follows.
・Measuring device: “Coulter Multisizer (registered trademark) III” (manufactured by Beckman Coulter Co., Ltd.)
・Aperture diameter: 50μm
・Analysis software: "Multicizer (registered trademark) III version 3.51" (manufactured by Beckman Coulter Co., Ltd.)
・Electrolyte: “Isoton (registered trademark) II” (manufactured by Beckman Coulter Co., Ltd.)
・Measurement conditions: By adding the sample dispersion liquid to 100 mL of the electrolyte solution, the particle size of 30,000 particles was adjusted to a concentration that can be measured in 20 seconds, and then 30,000 particles were measured again to determine the particle size. The volume median particle diameter _D50 was determined from the distribution.

[Circularity of fused particles]
The circularity of the fused particles was measured under the following conditions.
・Measuring device: Flow type particle image analyzer “FPIA-3000” (manufactured by Sysmex Corporation)
- Preparation of dispersion liquid: A dispersion liquid of fused particles was prepared by diluting it with deionized water so that the solid content concentration was 0.001 to 0.05% by mass.
・Measurement mode: HPF measurement mode

[Volume median particle diameter _D50 and CV value of toner particles]
The volume median particle diameter _D50 of the toner particles was measured as follows.
The measuring device, aperture diameter, analysis software, and electrolytic solution were the same as those used in the measurement of the volume median particle diameter _D50 of the aggregated particles described above.
・Dispersion liquid: Polyoxyethylene lauryl ether "Emulgen (registered trademark) 109P" (manufactured by Kao Corporation, HLB (Hydrophile-Lipophile Balance) = 13.6) was dissolved in the electrolyte to form a dispersion liquid with a concentration of 5% by mass. I got it.
・Dispersion conditions: Add 10 mg of a measurement sample of toner particles after drying to 5 mL of the above dispersion liquid, disperse for 1 minute using an ultrasonic disperser, then add 25 mL of the electrolyte solution, and then disperse using an ultrasonic disperser. The samples were dispersed for 1 minute to prepare a sample dispersion.
・Measurement conditions: By adding the sample dispersion liquid to 100 mL of the electrolyte solution, the particle size of 30,000 particles was adjusted to a concentration that can be measured in 20 seconds, and then the particle size of 30,000 particles was measured. The volume median particle diameter D ₅₀ and volume average particle diameter D _V were determined from the distribution.
Further, the CV value (%) was calculated according to the following formula.
CV value (%) = (standard deviation of particle size distribution/volume average particle diameter D _V ) x 100

[Evaluation method]
[Toner charge amount distribution]
0.6 g of toner and 19.4 g of ferrite carrier (ferrite core, silicone coat, saturation magnetization: 71 Am ² /kg) were placed in a 50 mL polypropylene bottle "PP Sample Bottle Wide Mouth" (manufactured by Sunplatec Co., Ltd.), and processed using a ball mill. After stirring for 20 minutes, 5 g was sampled and measured using a charge measuring device "q-test" (manufactured by Epping Co., Ltd.) under the following measurement conditions.
・Toner Flow (mL/min): 160
・Electrode Voltage (V): 4000
・Deposition Time(s): 2
Median q/d was defined as the toner charge amount Q/d (fC/10 μm). At that time, the specific density was set to 1.2 g/cm ³ , and the median diameter was set to the volume median particle diameter D ₅₀ of the toner. A graph of the charge amount distribution was created by connecting the obtained Q/d with a straight line in the range of -0.4 to 0.4 (fC/10 μm).
The charge amount distribution was evaluated based on the half-width of the maximum peak of the charge amount distribution (the width of the cut section when the distribution is cut at half the maximum peak height in the distribution). The smaller the value, the narrower the charge amount distribution.

[Image density of printed matter]
Using a commercially available printer "Microline (registered trademark) 5400" (manufactured by Oki Data Co., Ltd.) on high-quality paper "J paper A4 size" (manufactured by Fuji Xerox Co., Ltd.), the amount of toner adhering to the paper was 0.25 mg/cm. A solid image number ² was output without being fixed.
Next, we prepared the same printer with a variable temperature fixing unit, set the temperature of the fixing unit to 130°C, and fixed the toner at a speed of 1.5 seconds per A4 sheet in the vertical direction to obtain printed matter. .
Lay 30 sheets of high-quality paper "Excellent White Paper A4 size" (manufactured by Oki Data Co., Ltd.) under the printed matter, and measure the reflected image density of the solid image part of the printed matter using a colorimeter "SpectroEye" (manufactured by Gretag Macbeth, optical). The image density was determined by averaging the values measured at ten arbitrary points on the image. The larger the value, the better the image density.

[Production of resin]
[Manufacture of amorphous polyester resin A1]
Production example A1 (manufacture of resin A1-1)
The interior of a four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 3,880 g of propylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane was prepared. , 1544 g of ethylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane, 1578 g of terephthalic acid, 694 g of adipic acid, and 40 g of tin(II) di(2-ethylhexanoate) were added, and nitrogen was added. The temperature was raised to 235° C. under stirring under an atmosphere and held at 235° C. for 6 hours, and then the pressure inside the flask was further lowered and held at 8.3 kPa for 1 hour. After that, the flask was cooled to 215°C, returned to atmospheric pressure, 304g of trimellitic anhydride was added, and the temperature was maintained at 215°C for 1 hour. The reaction was carried out up to the point where resin A1-1 was obtained. Table 1 shows the physical properties of the obtained resin.

Production example A2 (manufacture of resin A1-2)
The interior of a four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 3558 g of propylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane was prepared. , 1416 g of ethylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane, 1229 g of terephthalic acid, 1518 g of dodecenylsuccinic anhydride, and 40 g of tin(II) di(2-ethylhexanoate) were added. The temperature was raised to 230° C. with stirring under a nitrogen atmosphere, and the temperature was maintained at 230° C. for 6 hours, and then the pressure inside the flask was further lowered and maintained at 8.3 kPa for 1 hour. Thereafter, the flask was cooled to 215°C, returned to atmospheric pressure, 279 g of trimellitic acid anhydride was added, and the temperature was maintained at 215°C for 1 hour. The pressure inside the flask was further lowered and the temperature was maintained at 8.3 kPa for 3 hours. Resin A1-2 was obtained. The physical properties are shown in Table 1.

[Manufacture of crystalline polyester resin C1]
Production example C1 (manufacture of resin C1-1)
The inside of a four-necked flask with an internal volume of 10 L equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3471 g of 1,10-decanediol and 4029 g of sebacic acid were added, and while stirring, 135 After raising the temperature to 135°C for 3 hours, the temperature was raised from 135°C to 200°C over 10 hours. Thereafter, 15 g of tin (II) di(2-ethylhexanoate) was added and the temperature was further maintained at 200°C for 1 hour.The pressure inside the flask was then lowered and the temperature was maintained for 1 hour under a reduced pressure of 8 kPa. I got 1. The physical properties are shown in Table 2.

[Manufacture of amorphous polyester resin E for pigment dispersion]
Production example E1 (manufacture of resin E-1)
The interior of a four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 3,880 g of propylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane was prepared. , 1544 g of ethylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane, 1709 g of terephthalic acid, 1485 g of dodecenylsuccinic anhydride, 43 g of tin(II) di(2-ethylhexanoate), and gallic acid. Add 4.3 g of acid, raise the temperature to 235°C with stirring under nitrogen atmosphere, hold at 235°C for 10 hours, then lower the pressure inside the flask and react to the desired softening point at 8.3 kPa. Resin E-1 was obtained. Table 3 shows the physical properties of the obtained resin.

Production example E2 (manufacture of resin E-2)
The interior of a four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 3,880 g of propylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane was prepared. , 1544 g of ethylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane, 1840 g of terephthalic acid, 849 g of dodecenylsuccinic anhydride, 41 g of tin(II) di(2-ethylhexanoate), and gallic acid. Add 4.1 g of acid, raise the temperature to 235°C with stirring under nitrogen atmosphere, hold at 235°C for 10 hours, then lower the pressure inside the flask and react to the desired softening point at 8.3 kPa. Resin E-2 was obtained. Table 3 shows the physical properties of the obtained resin.

Production example E3 (manufacture of resin E-3)
The inside of a four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 3,880 g of propylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane was prepared. , 1544 g of ethylene oxide (2.2) adduct of 2,2-bis(4-hydroxyphenyl)propane, 1972 g of terephthalic acid, 424 g of dodecenylsuccinic anhydride, 39 g of tin(II) di(2-ethylhexanoate), and gallic acid. Add 3.9 g of acid, raise the temperature to 235°C with stirring under a nitrogen atmosphere, hold at 235°C for 10 hours, then lower the pressure inside the flask and react to the desired softening point at 8.3 kPa. Resin E-3 was obtained. Table 3 shows the physical properties of the obtained resin.

Production example D1 (manufacture of resin D-1)
The interior of a 10 L four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 2,2-bis(4-hydroxyphenyl)propane propylene oxide (2.2 ) adduct, 818 g of terephthalic acid, 727 g of succinic acid, 30 g of tin(II) di(2-ethylhexanoate), and 3.0 g of 3,4,5-trihydroxybenzoic acid (gallic acid) were placed in a nitrogen atmosphere. While stirring, the temperature was raised to 235°C, and after holding at 235°C for 5 hours, the pressure inside the flask was lowered and held at 8 kPa for 1 hour. Thereafter, the pressure was returned to atmospheric pressure, and then cooled to 160°C, and while the temperature was maintained at 160°C, a mixture of 2756 g of styrene, 689 g of stearyl methacrylate, 142 g of acrylic acid, and 413 g of dibutyl peroxide was added dropwise over 1 hour. Thereafter, the temperature was maintained at 160° C. for 30 minutes, and then the temperature was raised to 200° C., the pressure inside the flask was further lowered, and the reaction was carried out at 8 kPa to a desired softening point to obtain resin D-1. As a result of measuring the physical properties, the softening point was 91°C, the glass transition temperature was 42°C, the acid value was 24mgKOH/g, and the crystallinity index was 1.8.

[Manufacture of resin particle dispersion]
Production Example X1 (Production of resin particle dispersion X-1)
300 g of resin A1-1, 360 g of methyl ethyl ketone, and 59 g of deionized water were placed in a 3 L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, and the mixture was heated at 73°C for 2 hours. to dissolve the resin. A 5% by mass aqueous sodium hydroxide solution was added to the obtained solution so that the degree of neutralization was 60% by mole based on the acid value of the resin, and the mixture was stirred for 30 minutes.
Next, while maintaining the temperature at 73° C. and stirring at 280 r/min (peripheral speed 88 m/min), 600 g of deionized water was added over 60 minutes to effect phase inversion emulsification. While continuously maintaining the temperature at 73°C, methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion. After that, the aqueous dispersion was cooled to 30°C while stirring at 280 r/min (peripheral speed 63 m/min), and then deionized water was added so that the solid content concentration was 20% by mass to disperse the resin particles. Liquid X-1 was obtained. Table 4 shows the volume median particle diameter _D50 and CV value of the obtained resin particles.

Production Example X2 (Production of resin particle dispersion X-2)
Resin particle dispersion X-2 was obtained in the same manner as Production Example X1, except that the type of resin used was changed as shown in Table 4. Table 4 shows the volume median particle diameter _D50 and CV value of the obtained resin particles.

Production Example Y1 (Production of resin particle dispersion Y-1)
A mixed solvent of 300 g of resin C1-1, 300 g of methyl ethyl ketone, and 41 g of deionized water was placed in a 3 L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, and the mixture was heated to 73 °C. The resin was dissolved over a period of 2 hours. A 5% by mass aqueous sodium hydroxide solution was added to the obtained solution so that the degree of neutralization was 55% by mole based on the acid value of the resin, and the mixture was stirred for 30 minutes.
Next, while maintaining the temperature at 73° C. and stirring at 280 r/min (peripheral speed 88 m/min), 600 g of deionized water was added over 60 minutes to effect phase inversion emulsification. While continuously maintaining the temperature at 73°C, methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion. Thereafter, the aqueous dispersion was cooled to 30°C while stirring at 280 r/min (peripheral speed 88 m/min), and then deionized water was added so that the solid content concentration was 20% by mass to disperse the resin particles. Liquid Y-1 was obtained. Table 4 shows the volume median particle diameter _D50 and CV value of the obtained resin particles.

Production example P1 (manufacture of resin particle dispersion P-1)
200 g of resin D-1 and 200 g of methyl ethyl ketone were placed in a 3 L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen inlet tube, and the resin was dissolved at 73° C. for 2 hours. Ta. A 5% by mass aqueous sodium hydroxide solution was added to the obtained solution so that the degree of neutralization was 60% by mole based on the acid value of the resin, and the mixture was stirred for 30 minutes.
Next, while maintaining the temperature at 73° C. and stirring at 280 r/min (peripheral speed 88 m/min), 700 g of deionized water was added over 50 minutes to effect phase inversion emulsification. While maintaining the temperature at 73° C., methyl ethyl ketone was distilled off under reduced pressure to obtain an aqueous dispersion. After that, the aqueous dispersion was cooled to 30°C while stirring at 280 r/min (peripheral speed 88 m/min), and then deionized water was added so that the solid content concentration was 20% by mass to disperse the resin particles. Liquid P-1 was obtained. The volume median particle diameter _D50 of the obtained resin particles was 0.09 μm, and the CV value was 23%.

[Manufacture of release agent particle dispersion]
Production example W1 (manufacture of release agent particle dispersion W-1)
In a beaker with an internal volume of 1 L, 120 g of deionized water, 86 g of resin particle dispersion P-1, and 40 g of paraffin wax "HNP-9" (manufactured by Nippon Seiro Co., Ltd., melting point 75 °C) were added, and the mixture was heated at 90 to 95 °C. The temperature was maintained to melt and stir to obtain a molten mixture.
The obtained molten mixture was further dispersed for 20 minutes using an ultrasonic homogenizer "US-600T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.) while maintaining the temperature at 90 to 95°C, and then heated to room temperature (20°C). Cooled. Deionized water was added to adjust the solid content concentration to 20% by mass to obtain a release agent particle dispersion W-1. The volume median particle diameter _D50 of the release agent particles in the dispersion was 0.47 μm, and the CV value was 27%.

[Manufacture of colorant particle dispersion]
Production example Z1 (production of colorant particle dispersion Z-1)
75 g of resin E-1 and 330 g of methyl ethyl ketone were placed in a 5 L container equipped with a stirrer equipped with a disper blade, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen introduction tube, and the resin was dissolved at 20°C. . To the obtained solution, 29 g of a 5% by mass aqueous sodium hydroxide solution (the degree of neutralization of resin E-1 becomes 80 mol%) was added, and further 632 g of deionized water was added, and the mixture was heated with a disper blade at 20°C. Stirred for 10 minutes. Next, 300 g of magenta pigment "Permanent Carmine 3810" (manufactured by Sanyo Shiki Co., Ltd., C.I. Pigment Red 269) was added, and stirring was performed at 20° C. for 2 hours at 6400 r/min with a disper blade. Thereafter, the mixture was passed through a 200 mesh filter and treated for 15 passes at a pressure of 150 MPa using a homogenizer "Microfluidizer M-110EH" (manufactured by Microfluidics). While stirring the resulting dispersion, methyl ethyl ketone and a portion of water were distilled off at 70° C. under reduced pressure. After cooling, it was passed through a 200 mesh filter, and deionized water was added so that the solid content concentration was 20% by mass to obtain colorant particle dispersion Z-1. Table 5 shows the volume median particle diameter _D50 and CV value of the obtained colorant particles.

Production examples Z2 to Z4 (manufacture of colorant particle dispersions Z-2 to Z-4)
Colorant particle dispersions Z-2 to Z-4 were obtained in the same manner as Production Example Z1, except that the types and amounts of raw materials used were changed as shown in Table 5. Table 5 shows the volume median particle diameter _D50 and CV value of the obtained colorant particles.

Production example Z5 (production of colorant particle dispersion Z-5)
Similarly to Production Example Z1, 75 g of Resin E-1 was dissolved in 330 g of methyl ethyl ketone, and 29 g of a 5% by mass aqueous sodium hydroxide solution (the neutralization degree of Resin E-1 was 80 mol%) was added to the resulting solution. ), and further 632 g of deionized water was added, followed by stirring at 20° C. for 10 minutes with a disper blade. Next, 300 g of magenta pigment "Permanent Carmine 3810" (manufactured by Sanyo Shiki Co., Ltd., C.I. Pigment Red 269) was added, and stirring was performed at 20° C. for 2 hours at 6400 r/min with a disper blade.
After that, it was passed through a 200 mesh filter, and using a bead mill "NVM-2" (manufactured by Imex Co., Ltd.), glass beads with a bead diameter of 0.6 mm were used at a filling rate of 80% by volume at a circumferential speed of 10 m/s. , 5 passes were performed at a liquid feeding rate of 0.6 kg/min. While stirring the resulting dispersion, methyl ethyl ketone and a portion of water were distilled off at 70° C. under reduced pressure. After cooling, it was passed through a 200 mesh filter, and deionized water was added so that the solid content concentration was 20% by mass to obtain colorant particle dispersion Z-5. Table 5 shows the volume median particle diameter _D50 and CV value of the obtained colorant particles.

Production example Z81 (production of colorant particle dispersion Z-81)
In a beaker with an internal volume of 1 L, 100 g of magenta pigment "Permanent Carmine 3810" (manufactured by Sanyo Shiki Co., Ltd., C.I. Pigment Red 269) and 15% by mass aqueous solution of sodium dodecylbenzenesulfonate "Neoperex G-15" (Kao Corporation) 167 g of anionic surfactant) and 102 g of deionized water were mixed at 20°C using a homomixer "T.K. After dispersing for 1 hour at a rotation speed of 8000 r/min, the mixture was treated for 15 passes at a pressure of 150 MPa using a homogenizer "Microfluidizer M-110EH" (manufactured by Microfluidics). Thereafter, it was passed through a 200 mesh filter, and deionized water was added so that the solid content concentration was 20% by mass to obtain colorant particle dispersion Z-81. Table 5 shows the volume median particle diameter _D50 and CV value of the obtained colorant particles.

[Manufacture of toner]
Example 1 (manufacture of toner 1)
In a 4-necked flask with an internal volume of 3 L equipped with a dehydration tube, a stirring device, and a thermocouple, add 450 g of resin particle dispersion X-1, 50 g of resin particle dispersion Y-1, and release agent particle dispersion W-1. 82 g of colorant particle dispersion Z-1, 20 g of a 10% by mass aqueous solution of polyoxyethylene (50) lauryl ether "Emulgen 150" (manufactured by Kao Corporation, nonionic surfactant), and 15% by mass. 17 g of a sodium dodecylbenzenesulfonate aqueous solution "Neoperex G-15" (manufactured by Kao Corporation, anionic surfactant) was mixed at a temperature of 25°C. Next, while stirring the mixture, a 4.8% by mass aqueous potassium hydroxide solution was added to an aqueous solution of 43g of ammonium sulfate dissolved in 580g of deionized water to adjust the pH to 8.5. After the dropwise addition, the temperature was raised to 62° C. over 2 hours, and the temperature was maintained at 62° C. until the volume median particle diameter D ₅₀ of the aggregated particles reached 5.2 μm to obtain a dispersion of aggregated particles.
To the resulting dispersion of aggregated particles, 48 g of sodium polyoxyethylene lauryl ether sulfate "Emar E-27C" (manufactured by Kao Corporation, anionic surfactant, effective concentration 27% by mass), 600 g of deionized water, and An aqueous solution containing 60 g of a 1 mol/L sulfuric acid aqueous solution was added. Thereafter, the temperature was raised to 75°C over 1 hour, held at 75°C for 30 minutes, 10 g of a 0.1 mol/L sulfuric acid aqueous solution was added, and further held at 75°C for 15 minutes. Thereafter, 10 g of a 0.1 mol/L sulfuric acid aqueous solution was added again, and the mixture was maintained at 75° C. until the circularity reached 0.970, thereby obtaining a dispersion of fused particles in which aggregated particles were fused.
The resulting fused particle dispersion was cooled to 30°C, the dispersion was suction filtered to separate the solid content, washed with deionized water at 25°C, and suction filtered at 25°C for 2 hours. Thereafter, vacuum drying was performed at 33° C. for 24 hours using a constant temperature vacuum dryer “DRV622DA” (manufactured by ADVANTEC) to obtain toner particles having a water content of 0.5% by mass or less. Table 6 shows the physical properties of the obtained toner particles.
100 parts by mass of toner particles, 2.5 parts by mass of hydrophobic silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., number average particle diameter: 0.04 μm), and hydrophobic silica "Cabosil (registered trademark) TS720" (manufactured by Cabot Japan Co., Ltd.) Toner 1 was obtained by putting 1.0 part by mass of the toner (manufactured by Toner Co., Ltd., number average particle size: 0.012 μm) into a Henschel mixer, stirring it, and passing it through a 150 mesh sieve. Table 6 shows the evaluation results of the obtained toner.

Examples 2 to 7 and Comparative Example 1 (manufacture of toners 2 to 7 and 81)
Toners 2 to 7 and 81 were prepared in the same manner as in Example 1, except that the types of resin particle dispersions and colorant particle dispersions used were changed as shown in Table 6. Table 6 shows the physical properties of the obtained toner particles and the evaluation results of the toner.

The results of Examples and Comparative Examples showed that the electrostatic image developing toner obtained by the present invention had a narrow charge amount distribution and high image density.
On the other hand, Comparative Example 1 in which a surfactant was used instead of the amorphous polyester resin E to disperse the colorant was inferior in image density and charge amount distribution.

Claims (8)

A method for producing a toner for developing an electrostatic image, comprising a step of aggregating and fusing resin particles and colorant particles in an aqueous medium,
The colorant particles contain a colorant and an amorphous polyester resin E,
The amorphous polyester resin E is a polycondensate of an alcohol component and a carboxylic acid component,
The carboxylic acid component contains at least one of succinic acid and its anhydride substituted with a hydrocarbon group having 4 or more and 20 or less carbon atoms,
The mass ratio of the colorant and the amorphous polyester resin E in the colorant particles (colorant/amorphous polyester resin E) is 50/50 or more and 95/5 or less. Electrostatic image development method for producing toner for use in The method for producing an electrostatic image developing toner according to claim 1, wherein the resin particles contain a crystalline polyester resin. The succinic acid and its anhydride substituted with a hydrocarbon group having 4 to 20 carbon atoms are substituted with succinic acid substituted with an alkenyl group having 4 to 20 carbon atoms, and an alkyl group having 4 to 20 carbon atoms. 3. The method for producing an electrostatic image developing toner according to claim 1, wherein the toner is at least one selected from succinic acid and anhydrides thereof. Any of claims 1 to 3, wherein the total content of succinic acid and its anhydride substituted with a hydrocarbon group having 4 to 20 carbon atoms in the carboxylic acid component is 5 mol% or more and 50 mol% or less. A method for producing an electrostatic image developing toner according to claim 1. The colorant particles are
Step a: After mixing the amorphous polyester resin E and an organic solvent, further mixing an aqueous medium to obtain a dispersion of the amorphous polyester resin E, and Step b: The amorphous polyester resin E obtained in step a. The method for producing an electrostatic image developing toner according to any one of claims 1 to 4, which is obtained by a method comprising a step of dispersing the obtained dispersion liquid and a colorant to obtain a dispersion liquid of colorant particles. . 6. The method for producing an electrostatic image developing toner according to claim 5, further comprising step c: removing an organic solvent from the dispersion of colorant particles obtained in step b. The electrostatic image according to claim 5 or 6, wherein step b is a step of dispersing the dispersion obtained in step a and a colorant using a homogenizer or a bead mill to obtain a colorant particle dispersion. A method for manufacturing toner for development. The method for producing a toner for developing an electrostatic image according to any one of claims 1 to 7, wherein the colorant is a naphthol-based azo pigment.