JP7406448B2 - Method for manufacturing toner for developing electrostatic images - Google Patents

Description

The present invention relates to a method for producing a toner for developing electrostatic images.

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, small particle size, and fixing properties that can support high speeds is to aggregate and fuse fine resin particles in an aqueous medium. 2. Description of the Related Art So-called chemical toner is produced by an aggregation-fusion method (emulsion aggregation method, aggregation-coalescence method) to obtain a toner.

Patent Document 1 discloses an amorphous polyester resin which is a polycondensate of a polyhydric carboxylic acid and a polyhydric alcohol containing a propylene oxide adduct of bisphenol A in an amount exceeding 50 mol% and 100 mol% or less based on the total polyhydric alcohol. and a core containing a crystalline polyester resin, and a coating layer containing an amorphous polyester resin covering the core, and the content of hydroxyiminodisuccinic acid or an alkali metal salt thereof is 5 ppm or more and 500 ppm or less. A method for producing a toner for developing an electrostatic image, which contains toner particles containing an aluminum element in an amount of 0.08 mass% or more and 0.25 mass% or less, is described.
Patent Document 2 describes a binder resin, 8 to 15% by mass of carbon black, a mold release agent, a naphthalene sulfonic acid formalin condensate, and one or more anionic surfactants having a sulfonic group or a sulfuric ester group. containing a specific ratio of the naphthalene sulfonic acid formalin condensate and the anionic surfactant to the carbon black, and the dielectric loss factor at 1kHz and 5V at 30°C and 90%RH. A method for producing a toner for developing an electrostatic image is described, characterized in that ε'' is 0.01 or more and 0.025 or less.

Patent Document 3 describes a method for producing an electrostatic image developing toner comprising a particle aggregate containing at least primary polymer particles, which is characterized in that a formalin polycondensate of naphthalene sulfonate is added. A method for producing a developing toner is described.
Patent Document 4 includes a step of fusing aggregated particles, which are aggregates of polyester resin particles, in an aqueous medium, and in the fusing step, at a temperature equal to or higher than the glass transition temperature of the polyester resin of the aggregated particles. , and adding an acidic substance to lower the pH in the aqueous medium by 0.1 or more and 3.0 or less than before adding the acidic substance, and reducing the pH after adding the acidic substance to 4.0 or more and 7.0 or less. A method for producing a toner for developing electrostatic images is described.

Japanese Patent Application Publication No. 2015-64449 Japanese Patent Application Publication No. 2012-208219 JP2008-209460A JP 2019-117239 Publication

However, when producing toner particles with a core-shell structure using a chemical method such as an aggregation-fusion method, the chargeability of the resulting toner decreases due to the influence of surfactants on the resin particles used to form the shell layer. It turned out that there was a problem with the image quality deteriorating.
The present invention relates to a method for producing a toner having a core-shell structure, which is produced by a chemical method such as an aggregation-fusion method, and is capable of obtaining a toner having excellent charging properties and good image quality.

The present inventors investigated factors that affect image quality in a chemical toner having a core-shell structure produced by an agglomeration-fusion method. As a result, in order to prevent further unnecessary agglomeration of the aggregated particles formed in the aggregation process and improve the dispersion stability of the aggregated particles in the fusion process, it is added after the aggregation process and before the fusion process. It has been found that by using a surfactant having a specific structure, a toner with excellent charging properties and good image quality can be obtained.

That is, the present invention relates to the following [1].
[1] A method for producing a toner for developing an electrostatic image, comprising the following steps 1 to 4 in this order, wherein the amorphous polyester resin B contains 50 mol % or more of an ethylene oxide adduct of bisphenol A as an alcohol component.
Step 1: Step of mixing and agglomerating polyester resin particles X containing crystalline polyester resin C and amorphous polyester resin A and colorant particles in an aqueous medium to obtain aggregated particles 1 Step 2: Step Step 3: Agglomerated particles 1 obtained in step 1 are aggregated with resin particles Y containing amorphous polyester resin B to obtain aggregated particles 2. Step 3: At a temperature below the melting point of crystalline polyester resin C. Step 4: Adding a naphthalene sulfonic acid formalin condensate to the aggregated particles 2. Step 4: Adding the aggregated particles to the aggregated particles 2 at a temperature higher than the glass transition temperature of the amorphous polyester resin B and higher than the melting point of the crystalline polyester resin C by -10°C. 2 to obtain toner particles

According to the present invention, there is provided a method for producing a toner that is capable of obtaining a toner having a core-shell structure that is produced by a chemical method such as an aggregation-fusion method and has excellent chargeability and good image quality.

[Method for manufacturing toner for developing electrostatic image]
The method for producing a toner for developing electrostatic images of the present invention includes the following steps 1 to 4 in this order, and the amorphous polyester resin B contains 50 mol % or more of an ethylene oxide adduct of bisphenol A as an alcohol component.
Step 1: Step of mixing and agglomerating polyester resin particles X containing crystalline polyester resin C and amorphous polyester resin A and colorant particles in an aqueous medium to obtain aggregated particles 1 Step 2: Step Step 3: Agglomerated particles 1 obtained in step 1 are aggregated with resin particles Y containing amorphous polyester resin B to obtain aggregated particles 2. Step 3: At a temperature below the melting point of crystalline polyester resin C. Step 4: Adding a naphthalene sulfonic acid formalin condensate to the aggregated particles 2 Step 4: Adding the aggregated particles to the aggregated particles at a temperature higher than the glass transition temperature of the amorphous polyester resin B and higher than the melting point of the crystalline polyester resin C by -10°C Step of fusing 2 to obtain toner particles

The reason why the electrostatic image developing toner (hereinafter also simply referred to as "toner") obtained by the production method of the present invention has excellent charging properties and good image quality is not clear, but it is thought to be as follows. .
In order to create a chemical toner that has both low-temperature fixability and heat-resistant storage stability, it is effective to create a toner with a core-shell structure in which the core contains a crystalline polyester resin and the shell contains an amorphous polyester resin. However, there was a problem that a toner with good image quality could not be obtained.
In the toner manufacturing process using the emulsion aggregation method, the agglomerated particles obtained in the aggregation process are held together at a temperature higher than the glass transition temperature (Tg) of the amorphous polyester resin that makes up the shell, resulting in fusion. At that time, a surfactant is added as a dispersion stabilizer before the fusing process in order to suppress unnecessary agglomeration of the formed aggregated particles and improve the dispersion stability of the aggregated particles. There is. We believe that the following causes may be responsible for the decline in image quality. In other words, in the fusion process, hydrophilic groups such as carboxy groups and hydroxyl groups of the amorphous polyester resin that forms the shell layer are exposed on the particle surface, and in addition, the surfactant is adsorbed, which facilitates particle dispersion in water. The resin particles of the core and shell are integrated by heat to obtain fused particles. For this reason, since there are many hydrophilic groups on the surface of the obtained fused particles, this adversely affects the charging property, such as a decrease in the amount of charge and an expansion of the distribution of the amount of charge between the toner particles. It was thought that the image quality would deteriorate and cause an image defect called fog.
To solve this problem, the present inventors have developed a condensate of naphthalene sulfonic acid and formalin, preferably a condensate of naphthalene sulfonic acid and formalin, as a surfactant added for the purpose of improving dispersion stability before the fusion process. We have found that the problem can be improved by using metal salts (hereinafter also simply referred to as "naphthalene sulfonic acid formalin condensates"). Surfactants with the structure of a condensate of naphthalene sulfonic acid and formalin or a metal salt thereof are known to have a small effect on lowering interfacial tension even though they are surfactants. It is thought that they exist, and that they exist partially associated due to the influence of their large hydrophobic groups. If the naphthalene sulfonic acid formalin condensate is present in water during the fusion process, its adsorption to the particle surface will be reduced by the adsorption of naphthalene sulfonic acid formalin condensate such as sodium dodecylbenzenesulfonate because the shell layer has an aromatic ring derived from bisphenol A ethylene oxide adduct. It is thought that the amount will be higher than that of surfactants. In addition, since the hydrophobic group is a naphthalene group and is structurally large and rigid, it is thought that adsorption to the particle surface has the effect of preventing surface exposure of hydrophilic groups such as hydroxyl and carboxyl groups derived from polyester. It is believed that the surface exposure of the hydrophilic groups in the resulting fused particles is suppressed, resulting in a toner with excellent chargeability and improved image quality.
Note that the above mechanism regarding the effects of the present invention is a conjecture, and is not limited thereto.

Definitions of various terms used in this specification are shown below.
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 and ratios of raw material monomers, and production conditions such as reaction temperature, reaction time, and cooling rate.
In the specification, the carboxylic acid component of the polyester resin includes not only the compound thereof, but also anhydrides that decompose during the reaction to produce acids, and alkyl esters of each carboxylic acid (alkyl group has 1 to 3 carbon atoms). Also included.
"Volume median particle size (D ₅₀ )" is a particle size at which the cumulative volume frequency calculated by volume fraction is 50% from the smallest particle size.
The coefficient of variation of particle size distribution (hereinafter also simply referred to as "CV value") is a value expressed by the following formula. The volume average particle size in the formula below is the particle size obtained by multiplying the particle size measured on a volume basis by the proportion of particles with that particle size value, and dividing the resulting value by the number of particles. be.
CV value (%) = [standard deviation of particle size distribution (μm) / volume average particle diameter (μm)] × 100

<Step 1>
Step 1 is to mix polyester resin particles X (hereinafter also simply referred to as "resin particles X") containing crystalline polyester resin C and amorphous polyester resin A with colorant particles in an aqueous medium. This is a step of obtaining aggregated particles 1 by aggregation. Here, in addition to the resin particles X and the colorant particles, it is preferable to aggregate the release agent particles, and the resin particle dispersion containing the resin particles It is more preferable to mix a release agent particle dispersion containing release agent particles depending on the conditions, and aggregate these particles.
[Resin particles X]
The resin particle dispersion used in step 1 contains resin particles X. In order to obtain low-temperature fixing properties, excellent charging properties, and high-quality images, the resin particles From the viewpoint of further improving the low-temperature fixability of the toner and further widening the non-offset temperature range, preferably the amorphous polyester resin A and the crystalline polyester resin C are contained in the same resin particle.

≪Amorphous polyester resin A≫
The amorphous polyester resin A contains, for example, a polycondensate of an alcohol component and a carboxylic acid component.
Examples of the amorphous polyester resin include polyester resin and modified polyester resin. 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, it is an amorphous composite resin containing a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component, and an addition polymer resin segment that is an addition polymer of raw material monomers containing a styrene compound. is 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 low-temperature fixability.
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 indicate the average number of added moles of alkylene oxide, and each The value of the sum of x and y is 1 or more, preferably 1.5 or more, more preferably 1.8 or more, and 16 or less, preferably 8 or less, more preferably 4 or less, and even more preferably is 3 or less, more preferably 2.5 or less).

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 content of the alkylene oxide adduct of bisphenol A is preferably 50 mol% or more, more preferably 70 mol% or more, even more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less in the alcohol component. and more preferably 100 mol%.
Further, the amorphous polyester resin A preferably contains 50 mol% or more of bisphenol A propylene oxide adduct as an alcohol component, more preferably 60 mol% or more, still more preferably 70 mol% or more, even more preferably 90 mol%. More preferably, it is 100 mol%. Since the amorphous polyester resin B constituting the shell layer contains 50 mol% or more of an ethylene oxide adduct of bisphenol A as an alcohol component, from the viewpoint of reducing the compatibility between the core and the shell, the amorphous polyester resin B constituting the core It is preferable that the polyester resin A contains a propylene oxide adduct of bisphenol A in the above range as an alcohol component.
Further, the amorphous polyester resin A includes a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component, and an addition polymer resin segment that is an addition polymer of a raw material monomer containing a styrene compound, and It is more preferable that the content of the propylene oxide adduct of bisphenol A in the alcohol component is within the above range.

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 oxide adducts of hydrogenated bisphenol A having 2 to 4 carbon atoms (average addition mol number 2 (12 or less) and cyclohexanedimethanol.
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, even more preferably 50 mol% or more, and preferably 90 mol% or less, More preferably it is 85 mol% or less, still more preferably 80 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 an aliphatic hydrocarbon group having 1 or more and 20 or less carbon atoms. Examples of the succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, and octenylsuccinic acid. Among these, fumaric acid, sebacic acid, and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms are preferred.
The amount of linear or branched aliphatic dicarboxylic acid in the carboxylic acid component is preferably 1 mol% or more, more preferably 3 mol% or more, even more preferably 10 mol% or more, even more preferably 20 mol% or more, and preferably is 80 mol% or less, more preferably 55 mol% or less, even more preferably 40 mol% or less.

The polyhydric carboxylic acid having a valence of 3 or more is preferably a trivalent carboxylic acid, such as trimellitic acid. Preferred is 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% or more in the carboxylic acid component. , and preferably 30 mol% or less, more preferably 25 mol% or less, and even more preferably 20 mol% or less.
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.

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 preferably 2-ethylhexyl (meth)acrylate or ( Stearyl meth)acrylate, more preferably stearyl (meth)acrylate, still more preferably stearyl methacrylate.
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. The content 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 amorphous polyester resin A 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 based on 100 mol parts of the alcohol component of the polyester resin segment of the amorphous polyester resin A. is at least 1 mol part, more preferably at least 5 mol parts, even more preferably at least 8 mol parts, and is preferably at most 30 mol parts, more preferably at most 25 mol parts, even more preferably at most 20 mol parts.

The content of the polyester resin segment in the amorphous polyester resin A 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 85% by mass or less, still more preferably 75% by mass or less.

The content of the addition polymerized resin segment in the amorphous polyester resin A 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. The content is more preferably 55% by mass or less, still more preferably 45% by mass or less.

The amount of structural units derived from the bireactive monomer in the amorphous polyester resin A is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 0.8% by mass or more. The content is preferably 10% by mass or less, more preferably 7% by mass or less, even 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 amorphous polyester resin A is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass. It is at least 100% by mass, and more preferably 100% by mass.

The above amounts are calculated based on the ratio of the amounts of raw material monomers, bireactive monomers, and radical polymerization initiators for the polyester resin segment, addition polymerization resin segment, and exclude the amount of dehydration due to polycondensation in the polyester resin segment, etc. Use as a standard. 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 amorphous polyester resin A is 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 polymerization resin segment and a bireactive monomer are addition-polymerized. You can.
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 remainder of the carboxylic acid component is added to the polymerization system to complete 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 radical polymerization initiators 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.

(Physical properties of amorphous polyester resin A)
The softening point of the amorphous polyester resin A is preferably 70°C or higher, more preferably 90°C or higher, even more preferably 100°C or higher, and from the viewpoint of further improving low-temperature fixability, preferably 150°C. The temperature is more preferably 140°C or lower, and even more preferably 125°C or lower.
The glass transition temperature of the amorphous polyester resin A is preferably 30°C or higher, more preferably 35°C or higher, even more preferably 40°C or higher, and from the viewpoint of further improving low-temperature fixability, preferably 80°C or higher. The temperature is preferably 70°C or lower, even more preferably 60°C or lower.

The acid value of the amorphous polyester resin A 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 35 mgKOH/g. /g or less, more preferably 30 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of the amorphous polyester resin A can be adjusted as appropriate depending on the type of raw material monomer and its usage amount, and manufacturing conditions such as reaction temperature, reaction time, and cooling rate. Moreover, those values are determined by the method described in the Examples.
In addition, when using a combination of two or more types of amorphous polyester resin A, 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.

The content of the amorphous polyester resin A is preferably 40% by mass or more, more preferably 50% by mass or more, still more preferably 60% by mass or more, and even more preferably is 65% by mass or more, and preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less.

≪Crystalline polyester resin C≫
The crystalline polyester resin C is, for example, a crystalline polyester resin that is a polycondensate of an alcohol component and a carboxylic acid component.
Crystalline polyester resin is a polycondensate of an alcohol component and a carboxylic acid component.
As the alcohol component, α,ω-aliphatic diol is preferred.
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, 1,6-hexanediol, 1,10-decanediol, and 1,12-dodecanediol are preferred, and 1,10-decanediol is more 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 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-propanediol and neopentyl glycol; aromatic diols such as alkylene oxide adducts of bisphenol A; glycerin, pentyl glycol, etc. Trihydric or higher alcohols such as erythritol and trimethylolpropane can be mentioned. These alcohol components may be used alone or in combination of two or more.

As the carboxylic acid component, aliphatic dicarboxylic acids are preferred, and linear aliphatic dicarboxylic acids are more preferred.
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 and dodecanedioic acid are 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, even more preferably 95 mol% or more, and 100 mol% or less, More preferably, it is 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.

Examples of the method for producing the crystalline polyester resin include the same example as in Step A of the amorphous polyester resin A described above.

(Physical properties of crystalline polyester resin C)
The softening point of the crystalline polyester resin C is preferably 60°C or higher, more preferably 70°C or higher, and even more preferably 80°C or higher from the viewpoint of toner storage stability, and from the viewpoint of further improving low-temperature fixability. , preferably 150°C or lower, more preferably 120°C or lower, and still more preferably 100°C or lower.
The melting point of the crystalline polyester resin C is preferably 50° C. or higher, more preferably 60° C. or higher, and even more preferably 70° C. or higher from the viewpoint of toner storage stability, and from the viewpoint of further improving low-temperature fixability. , preferably 100°C or lower, more preferably 90°C or lower, even more preferably 80°C or lower.

The acid value of the crystalline polyester resin C is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, and preferably 35 mgKOH/g or less, more preferably 25 mgKOH/g or less, even more preferably 20 mgKOH/g. It is as follows.
The softening point, melting point, and acid value of the crystalline polyester resin C can be adjusted as appropriate depending on the type and amount of raw material monomers used, and manufacturing conditions such as reaction temperature, reaction time, and cooling rate. It is determined by the method described in . In addition, when using a combination of two or more types of crystalline polyester resins, it is preferable that the values of the softening point, melting point, and acid value of the mixture are each within the above ranges.

The content of the crystalline polyester resin C is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, based on the total amount of resin components of the resin particles X, and Preferably it is 60% by mass or less, more preferably 50% by mass or less, still more preferably 40% by mass or less, still more preferably 35% by mass or less.
The mass ratio of the amorphous polyester resin A and the crystalline polyester resin C [amorphous polyester resin A/crystalline polyester resin C] is preferably 50/50 or more, more preferably 55/45 or more, and Preferably it is 60/40 or more, more preferably 65/35 or more, and preferably 95/5 or less, more preferably 90/10 or less, still more preferably 85/15 or less.

<<Preparation of resin particle dispersion>>
A resin particle dispersion containing resin particles X, preferably a resin particle dispersion containing amorphous polyester resin A and crystalline polyester resin C in the same or different resin particles, is prepared using a known method. However, it is preferable to disperse by 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 from the viewpoint of facilitating phase inversion, for example, alcoholic solvents such as ethanol, isopropanol, isobutanol; acetone, methyl ethyl ketone, methyl isobutyl ketone. , ketone solvents such as diethyl ketone; ether solvents such as dibutyl ether, tetrahydrofuran, and dioxane; and acetate ester solvents such as ethyl acetate and isopropyl acetate. Among these, ketone solvents and acetate ester solvents are preferred, and methyl ethyl ketone, ethyl acetate, and isopropyl acetate are more preferred, from the viewpoint of easy removal from the mixed solution after addition of the aqueous medium.
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 equivalent amount (mol%) of the neutralizing agent used with respect to the acid groups of the resin contained in the resin particles X is preferably 10 mol% or more, more preferably from the viewpoint of obtaining fine resin particles and improving dispersion stability. is 30 mol% or more, more preferably 40 mol% or more, and preferably 90 mol% or less, more preferably 70 mol% or less.
Note that the equivalent amount (mol%) of the neutralizing agent used can be determined by the following formula. The equivalent amount of the neutralizing agent used is synonymous with the degree of neutralization when it is 100 mol% or less.
Equivalent amount of neutralizing agent used (mol%) = [{Added mass of neutralizing agent (g)/Equivalent weight of neutralizing agent}/[{Weighted average acid value of resin constituting resin particle X (mgKOH/g)× Mass (g) of resin constituting resin particle X}/(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 at least the glass transition temperature of the resin constituting the resin particles X, more preferably at least 50°C, and even more preferably at least 50°C, from the viewpoint of improving the dispersion stability of the resin particles X. is 60°C or higher, and preferably 85°C or lower, more preferably 80°C or lower.
The contents of the amorphous polyester resin A and the crystalline polyester resin C are as described above.

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% by mass.

The volume median particle diameter (D ₅₀ ) of the resin particles X in the dispersion is preferably 0.05 μm or more, more preferably 0.08 μm or more, and even more preferably It is 0.12 μm or more, and preferably 0.8 μm or less, more preferably 0.4 μm or less, and still 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 35% or less, more preferably 30% or less.
The volume median particle diameter (D ₅₀ ) and CV value of the resin particles X are determined by the method described in Examples below.

Note that when using a mixture of resin particles Xa containing amorphous polyester resin A and resin particles Xc containing crystalline polyester resin C, resin particles Xa and Xc can be obtained by the same method as described above. can.
The amount of resin particles Xa and resin particles Xc added is preferably an amount that corresponds to the content of the amorphous polyester resin A and crystalline polyester resin C described above.

[Aqueous medium]
In the present invention, the aqueous medium is a medium whose main component is water, and the content of water in the aqueous medium is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass. or more, and 100% by mass or less. As water, deionized water, ion-exchanged water, or distilled water is preferred.
Components other than water that can constitute an aqueous medium together with water include alkyl alcohols with 1 to 5 carbon atoms; dialkyl ketones with 3 to 5 carbon atoms such as acetone and methyl ethyl ketone; and cyclic ethers such as tetrahydrofuran that dissolve in water. An organic solvent is used. Among these, alkyl alcohols having 1 or more and 5 or less carbon atoms are preferred, and methanol or ethanol is more preferred.

[Colorant particles]
The colorant particles are mixed with the resin particle dispersion described above as a colorant particle dispersion in which colorant particles containing the colorant are dispersed in an aqueous medium.

≪Coloring agent≫
In step 1, colorant particles containing a colorant are aggregated together with resin particles X. As the colorant, all dyes, pigments, etc. used as colorants for toners can be used.
Examples of colorants include carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, and disazo yellow. It will be done. The toner may be either a black toner or a color toner other than black.

(Colorant particle dispersion)
It is preferable that the colorant be contained in the aggregated particles by mixing the colorant particles with the resin particles as a dispersion and coagulating the mixture.
The colorant particle dispersion is preferably obtained by dispersing the colorant and an aqueous medium using a disperser such as a homogenizer or an ultrasonic disperser. The dispersion is carried out in the presence of an addition polymer (hereinafter, the addition polymer used for dispersing the colorant is also referred to as "addition polymer E") or a surfactant, from the viewpoint of improving the dispersion stability of the colorant. It is preferable to do so. Examples of the surfactant include nonionic surfactants, anionic surfactants, and cationic surfactants, and from the viewpoint of improving the dispersion stability of colorant particles, anionic surfactants are preferable. It is a drug. Examples of the anionic surfactant include dodecylbenzene sulfonate, dodecyl sulfate, lauryl ether sulfate, and alkenyl succinate. Among these, dodecylbenzenesulfonate is preferred.
From the viewpoint of improving the dispersion stability of the colorant, the content of the surfactant in the colorant particle dispersion is preferably 1 part by mass or more, more preferably 5 parts by mass or more, based on 100 parts by mass of the colorant. , more preferably 10 parts by mass or more, and preferably 40 parts by mass or less, more preferably 30 parts by mass or less.

The addition polymer E is preferably an addition polymer of raw material monomers containing an addition polymerizable monomer a (hereinafter also simply referred to as "monomer a") having an aromatic group. It is more preferable that the addition polymer E includes a structural unit derived from the addition polymerizable monomer a having an aromatic group in its main chain.
The raw material monomers for the addition polymer E contain, in addition to the addition polymerizable monomer a having an aromatic group, more preferably an addition polymerizable monomer b having an ionic group (hereinafter also simply referred to as "monomer b").
In addition to monomer b, the raw material monomers for addition polymer E are preferably addition polymerizable monomer c (hereinafter also simply referred to as "monomer c") or macromonomer d (hereinafter referred to as "monomer c") having a polyalkylene oxide group. It further contains at least one selected from the group consisting of monomers (also simply referred to as "monomers d").

The addition polymerizable monomer a having an aromatic group is preferably nonionic.
Examples of the addition polymerizable monomer a having an aromatic group include a styrene compound a-1 and an aromatic group-containing (meth)acrylate a-2.
Examples of the styrene compound a-1 include substituted or unsubstituted 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 sulfo group, or a salt thereof.
The molecular weight of the styrenic compound a-1 is preferably 1,000 or less, more preferably 800 or less, even more preferably 500 or less, even more preferably 300 or less, and preferably 80 or more, more preferably 90 or more, More preferably, it is 100 or more.
Examples of the styrenic compound a-1 include styrene, methylstyrene, α-methylstyrene, β-methylstyrene, tert-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid or a salt thereof. . Among these, styrene is preferred.
From the viewpoint of further improving hot offset resistance and image quality, the amount of styrene compound a-1 is preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, even more preferably 35% by mass or more, and preferably 98% by mass or less, more preferably 80% by mass or less, even more preferably is 65% by mass or less, more preferably 50% by mass or less.

Examples of the aromatic group-containing (meth)acrylate a-2 include benzyl (meth)acrylate and phenoxyethyl (meth)acrylate.
The molecular weight of the aromatic group-containing (meth)acrylate a-2 is preferably 1,000 or less, more preferably 800 or less, even more preferably 500 or less, even more preferably 300 or less, and preferably 160 or more. .
When using aromatic group-containing (meth)acrylate a-2, from the viewpoint of further improving hot offset resistance and image quality, the content of aromatic group-containing (meth)acrylate a-2 is adjusted to In the raw material monomer of E, preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably is 30% by mass or less.

From the viewpoint of further improving image density, the amount of the addition polymerizable monomer a having an aromatic group is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, even more preferably 35% by mass or more, and preferably 98% by mass or less, more preferably 95% by mass or less, even more preferably is 90% by mass or less, more preferably 80% by mass or less, even more preferably 65% by mass or less, even more preferably 50% by mass or less.

The ionic group in monomer b means a group that ionically dissociates in water.
Examples of the ionic group include a carboxy group, a sulfo group, a phosphoric acid group, an amino group, or a salt thereof.
The ionic group is preferably an anionic group from the viewpoint of improving the dispersion stability of the colorant particles. The anionic group is preferably an acidic group or a salt thereof, more preferably a carboxy group, a sulfo group, or a salt thereof, and even more preferably a carboxy group or a salt thereof.
Examples of the addition polymerizable monomer having a carboxyl group include (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, and 2-methacryloyloxymethylsuccinic acid.
Among these, addition polymerizable monomers having an anionic group are preferred, (meth)acrylic acid is more preferred, and methacrylic acid is even more preferred.
When containing monomer b, the amount of monomer b is preferably 2% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, and preferably is 40% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less.

The average number of moles of alkylene oxide added to the polyalkylene oxide group of monomer c is preferably 1 or more, more preferably 2 or more, even more preferably 3 or more, and preferably 30 or less, more preferably 20 or less, and Preferably it is 10 or less.
Monomer c is preferably nonionic.
Examples of the monomer c include polyalkylene glycol (meth)acrylates such as polyethylene glycol (meth)acrylate and polypropylene glycol (meth)acrylate; alkoxypolyalkylene glycol (meth)acrylates such as methoxypolyethylene glycol (meth)acrylate; phenoxy ( Examples include aryloxypolyalkylene glycol (meth)acrylates such as ethylene glycol-propylene glycol copolymerized (meth)acrylates.
When containing monomer c, the amount of monomer c is preferably 3% by mass or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, and preferably is 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less.

Examples of the monomer d include a styrene compound polymer having an addition-polymerizable functional group at one end (hereinafter also referred to as "styrene macromonomer"). Examples of the addition polymerizable functional group include a vinyl group, an allyl group, and a (meth)acryloyl group. Among these, a (meth)acryloyl group is preferred.
In monomer d, styrene is preferred as the styrene compound.
The number average molecular weight of the monomer d is preferably 1,000 or more and 10,000 or less. Note that the number average molecular weight is measured by gel permeation chromatography using chloroform containing 1 mmol/L of dodecyldimethylamine as a solvent and using polystyrene as a standard substance.
Commercially available styrenic macromonomers include, for example, "AS-6", "AS-6S", "AN-6", "AN-6S", "HS-6", "HS-6S" (the above, manufactured by Toagosei Co., Ltd.).
When containing monomer d, the amount of monomer d is preferably 3% by mass or more, more preferably 6% by mass or more, still more preferably 10% by mass or more, and preferably is 30% by mass or less, more preferably 25% by mass or less, even more preferably 20% by mass or less.

Furthermore, the raw material monomers for addition polymer E may contain addition polymerizable monomers (other monomers) other than monomers a to d.
Examples of other monomers include alkyl (meth)acrylates having an alkyl group having 1 to 22 carbon atoms (preferably 6 to 18 carbon atoms).
When containing other monomers, the amount of the other monomers is preferably 40% by mass or less, more preferably 30% by mass or less, still more preferably 20% by mass or less, even more preferably It is 10% by mass or less, more preferably 5% by mass or less.

The weight average molecular weight of the addition polymer E is preferably 3,000 or more, more preferably 5,000 or more, still more preferably 20,000 or more, still more preferably 40,000 or more, from the viewpoint of further improving image density. More preferably, it is 48,000 or more, and preferably 200,000 or less, more preferably 90,000 or less, still more preferably 60,000 or less, and still more preferably 53,000 or less. Note that the weight average molecular weight can be measured by the method described in Examples.

Addition polymer E can be produced, for example, by copolymerizing raw material monomers by a known polymerization method. The polymerization method is preferably a solution polymerization method in which raw monomers are heated and polymerized together with a polymerization initiator, a polymerization chain transfer agent, etc. in a solvent.
Examples of the polymerization initiator include peroxides such as dibutyl peroxide, persulfates such as sodium persulfate, and azo compounds such as 2,2'-azobis(2,4-dimethylvaleronitrile).
The amount of the polymerization initiator added is preferably 0.5 parts by mass or more and preferably 30 parts by mass or less based on 100 parts by mass of the raw material monomer.
Examples of the polymerization chain transfer agent (also simply referred to as "chain transfer agent") include mercaptans such as 2-mercaptoethanol and 3-mercaptopropionic acid.
The amount of the polymerization chain transfer agent added is preferably 0.01 parts by mass or more and preferably 10 parts by mass or less with respect to 100 parts by mass of the raw material monomer.
After completion of the polymerization reaction, the produced polymer may be isolated and purified from the reaction solution by known methods such as reprecipitation and solvent distillation.

In the colorant particles, the mass ratio of the colorant to the addition polymer E (colorant/addition polymer E) is preferably 50/50 or more, more preferably 50/50 or more, from the viewpoint of obtaining a toner with excellent hot offset resistance and image quality. is 60/40 or more, more preferably 70/30 or more, even more preferably 75/25 or more, and is preferably 95/5 or less, more preferably 90/10 or less, and still more preferably 85/15 or less. .

<<Method for producing colorant particles and colorant particle dispersion>>
Colorant particles are obtained, for example, by mixing a colorant and addition polymer E.
There is no particular restriction on the method for producing the colorant particle dispersion, and it may be possible to control the method to produce colorant particles with a desired volume median particle diameter _D50 using a known kneader, dispersion machine, etc., but preferably coloring It is obtained by mixing the agent and a dispersion of addition polymer E using a bead mill or a homogenizer.

The method for producing colorant particles preferably includes:
Step a: After mixing addition polymer E and an organic solvent, a neutralizing agent is mixed if necessary, and an aqueous medium is further mixed to obtain a dispersion of addition polymer E, and Step b: This method includes a step of dispersing the dispersion obtained in step a and a colorant to obtain a dispersion of colorant particles (colorant particle dispersion 2).
By including the organic solvent, the addition polymer E is dissolved in the organic solvent, and the addition polymer 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 bead mill or a homogenizer.

In step a, it is preferable to first mix addition polymer E and an organic solvent to dissolve addition polymer E.
Examples of the organic solvent used here include alkyl alcohols having 1 to 3 carbon atoms, dialkyl ketones having 3 to 5 total carbon atoms, 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 addition polymer 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.
The degree of neutralization of addition polymer E is preferably 15 mol% or more, more preferably 20 mol% or more, even more preferably 40 mol% or more, still more preferably 60 mol% or more, still more preferably 70 mol% or more, and preferably It is 100 mol% or less, more preferably 90 mol% or less, even more preferably 80 mol% or less.
Note that the degree of neutralization of addition polymer E can be determined by the following formula.
Degree of neutralization (mol%) = [{added mass of neutralizing agent (g)/equivalent weight of neutralizing agent}/{mass proportion of addition polymerizable monomer having acidic groups constituting addition polymer E x addition polymer Mass of E (g)/molecular weight of addition polymerizable monomer having acidic group}]×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, 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 30 hours, more preferably at most 10 hours, even more preferably at most 5 hours, even more preferably is 3 hours or less, more preferably 1 hour or less.

In step b, the mass ratio of the colorant and addition polymer E [colorant/addition polymer E] is as described above.
In step b, it is preferable that the dispersion obtained in step a and the colorant are mixed and then subjected to a dispersion treatment. As the device used for mixing in step b, the same device as the device used for mixing in step a is exemplified.
The temperature during mixing in step b 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 still more preferably 25°C or lower.
Further, the mixing time in step b is preferably 1 minute or more, more preferably 10 minutes or more, even more preferably 30 minutes or more, and preferably 30 hours or less, more preferably 10 hours or less, even more preferably 5 The time is preferably 3 hours or less, more preferably 3 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.
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 8 or more, even more preferably 12 or more, and preferably 30 or less, more preferably 20 or less.

It is preferable to remove the organic solvent from the obtained colorant particle dispersion.
Further, the colorant particle dispersion liquid is preferably filtered through a wire mesh or the like to remove coarse particles and the like. Further, from the viewpoint of improving the productivity and storage stability of the dispersion, the addition polymer E of the colorant particles may be subjected to a crosslinking treatment.
Furthermore, various additives such as organic solvents, preservatives, and antifungal agents may be added to the colorant particle dispersion.

In the colorant particle dispersion, the colorant is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass. % or less, more preferably 25% by mass or less.
The solid content concentration of the colorant particle dispersion 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 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 in the colorant particle dispersion is preferably 0.05 μm or more, more preferably 0.07 μm or more, and still more preferably 0.08 μm or more. and is preferably 0.4 μm or less, more preferably 0.3 μm or less, and even more preferably 0.2 μm or less.
The CV value of the colorant particles in the colorant particle dispersion is preferably 10% or more, more preferably 15% or more, and preferably 45% or less, more preferably 40% or more, from the viewpoint of improving image density. % or less, more preferably 35% or less.
The volume median particle diameter _D50 and CV value of the colorant particles are measured by the method described in the Examples.

The amount of the colorant particles is preferably 3 parts by mass or more, more preferably 6 parts by mass or more, still more preferably 10 parts by mass or more, and even more preferably is 15 parts by mass or more, and preferably 40 parts by mass or less, more preferably 30 parts by mass or less, still more preferably 25 parts by mass or less.

[Mixing conditions]
In step 1, it is preferable to mix the resin particles X and colorant particles in an aqueous medium and aggregate the resin particles X and colorant particles to obtain aggregated particles. The resin particles X and the colorant particles are preferably mixed by mixing a resin particle dispersion containing the resin particles X and a colorant particle dispersion containing the colorant particles. Further, the resin particle dispersion is preferably an aqueous dispersion of resin particles, and the colorant particle dispersion is preferably an aqueous dispersion of colorant particles.
In step 1, it is preferable to aggregate the release agent particles together with the resin particles X and the colorant particles.

≪Release agent≫
In step 1, it is preferable to aggregate mold release agent particles containing a mold release agent together with the resin particles X and colorant particles.
Examples of mold release agents include polypropylene wax, polyethylene wax, polypropylene polyethylene copolymer wax; hydrocarbon waxes such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and Sasol wax; or their oxides; carnauba wax; , montan wax or their deoxidized waxes, and ester waxes such as 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.

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 140°C or lower, still more preferably 120°C or lower, even more preferably 100°C or lower. It is.
The content 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 20% by mass or less, more preferably It is 15% by mass or less.

(Dispersion of release agent particles)
The release agent is preferably contained in aggregated particles by mixing the release agent particle dispersion with a resin particle dispersion and a colorant particle dispersion and coagulating the mixture.
Although the dispersion of mold release agent particles can be obtained using a surfactant, it is preferably obtained by mixing the mold release agent and resin particles Z described below. By preparing the mold release agent particles using a mold release agent and resin particles Z, the mold release agent particles are stabilized by the resin particles Z, 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 the release agent particles has a structure in which many resin particles Z are attached to the surface of the release agent particles.

The resin constituting the resin particles Z in which the release agent is dispersed is preferably a polyester resin, and it is more preferable to use a composite resin D having a polyester resin segment and an addition polymerized resin segment.

The softening point of the composite resin D is preferably 70°C or higher, more preferably 80°C or higher, even more preferably 90°C or higher, and preferably 140°C or lower, more preferably 125°C or lower, and still more preferably 110°C. It is as follows.
The acid value of the composite resin D is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, and even more preferably 15 mgKOH/g from the viewpoint of obtaining fine resin particles and fine release agent particle dispersion. Above, it is more preferably 20 mgKOH/g or more, and preferably 40 mgKOH/g or less, more preferably 35 mgKOH/g or less, still more preferably 30 mgKOH/g or less.

Preferred ranges of other resin properties of composite resin D, preferred examples of raw material monomers constituting the resin, etc. are the same as the examples shown for amorphous polyester resin A. The dispersion liquid of resin particles Z can be obtained, for example, by the above-mentioned phase inversion emulsification method.
The volume median particle diameter (D ₅₀ ) of the resin particles Z is preferably 0.01 μm or more, more preferably 0.03 μm or more, and preferably 0.01 μm or more, more preferably 0.03 μm or more, from the viewpoint of dispersion stability of the release agent particles. It is 3 μm or less, 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 Z is preferably 10% or more, more preferably 15% or more, and preferably 40% or less, more preferably 35% or less, More preferably, it is 30% or less.
The volume median particle diameter (D ₅₀ ) and CV value of the resin particles Z are measured by the method described in the Examples.

The release agent particle dispersion can be prepared by, for example, adding a dispersion of the release agent and resin particles Z, and optionally an aqueous medium, 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 disperser such as
The heating temperature during dispersion is preferably higher than the melting point of the mold release agent and higher than 80°C, more preferably higher than 85°C, even more preferably higher than 90°C, and preferably softens the resin contained in the resin particles Z. 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 Z is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 20 parts by mass or more, and preferably 100 parts by mass or less, based on 100 parts by mass of the mold release agent. , more preferably 70 parts by mass or less, still 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 0.4 μm or more, from the viewpoint of obtaining uniform agglomerated particles by aggregation. It is preferably 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 (D ₅₀ ) and CV value of the release agent particles are measured by the method described in the Examples.

The aggregated particles 1 also contain additives such as charge control agents, magnetic powders, fluidity improvers, conductivity modifiers, reinforcing fillers such as fibrous substances, antioxidants, anti-aging agents, and cleaning performance improvers. May contain.

≪Surfactant≫
In step 1, after preparing a mixed dispersion in which a resin particle dispersion, optionally a colorant particle dispersion, and a release agent particle dispersion are mixed, resin particles X, and optionally colorant particles, Agglomerate the release agent particles.
When preparing the mixed dispersion liquid, from the viewpoint of improving the dispersion stability of the resin particles X and optional components such as colorant particles and mold release agent particles added as necessary, it is carried out in the presence of a surfactant. You can. 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. Further, as a surfactant, a naphthalene sulfonic acid formalin condensate, which will be described later, may be used in an amount smaller than the amount used during fusion. In this case as well, a naphthalene sulfonic acid formalin condensate is separately added in step 3 described below. One type or two or more types of surfactants may be used.
When a surfactant is used, the amount used is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, based on 100 parts by mass of the resin particles X as the total amount of surfactant. The amount is preferably 5 parts by mass or less, more preferably 2 parts by mass or less.

The above-mentioned dispersion of resin particles X 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 flocculants include cationic surfactants such as quaternary salts, organic flocculants such as polyethyleneimine; inorganic metal salts such as sodium sulfate, sodium nitrate, sodium chloride, calcium chloride, and calcium nitrate; ammonium sulfate, chloride, etc. Examples include inorganic ammonium salts such as ammonium and ammonium nitrate; inorganic flocculants such as divalent or higher valent metal complexes. From the viewpoint of improving cohesiveness and obtaining uniform aggregated 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 ammonium sulfate is even more preferable. . Although the flocculant may be added as it is, it is preferable to dissolve it in an aqueous medium and add it as an aqueous solution. Further, when adding the flocculant as an aqueous solution, the pH of the aqueous flocculant solution may be adjusted.

Using a flocculant, for example, 5 parts by mass per 100 parts by mass of resin particles X is added to a mixed dispersion containing resin particles Agglomerated particles 1 are obtained by adding 50 parts by mass or less of an aggregating agent and aggregating the resin particles X and colorant particles in an aqueous medium. Furthermore, from the viewpoint of promoting aggregation, it is preferable to raise the temperature of the dispersion after adding the flocculant.

The volume median particle diameter D ₅₀ of the aggregated particles 1 obtained in step 1 is preferably 3 μm or more, more preferably 4 μm or more, even more preferably 5 μm or more, and preferably 10 μm or less, more preferably 8 μm or less. , more preferably 6 μm or less.
Preferably, the aggregation step is continued until the desired volume median particle size is achieved.

<Step 2>
Step 2 is a step in which resin particles Y containing amorphous polyester resin B are attached to the aggregated particles 1 obtained in Step 1 and aggregated to obtain aggregated particles 2. The act of adhering the resin particles Y to the aggregated particles 1 and causing them to aggregate is also simply referred to as "agglomerating".
[Resin particles Y]
The resin particle dispersion used in step 2 contains resin particles Y, and the resin particles Y contain amorphous polyester resin B.

≪Amorphous polyester resin B≫
It is preferable that the amorphous polyester resin B is, for example, an amorphous polyester resin containing a polycondensate of an alcohol component and a carboxylic acid component.
Examples of the 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 which are polycondensates of alcohol components and carboxylic acid components are preferred.

The alcohol component is selected from the viewpoints of low-temperature fixing properties, heat-resistant storage stability, charging properties, and high image quality. Contains 50 mol% or more of ethylene oxide adduct of bisphenol A. The content of the ethylene oxide adduct of bisphenol A is preferably 60 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, and still more preferably 100 mol%.
The average number of added moles of ethylene oxide is 1 or more, preferably 1.5 or more, more preferably 1.8 or more, preferably 16 or less, more preferably 8 or less, still more preferably 4 or less, still more preferably 3 or less. , more preferably 2.5 or less.

In addition to the ethylene oxide adduct of bisphenol mentioned above, alcohol components include a propylene oxide adduct of bisphenol A, the linear or branched aliphatic diols mentioned above in the amorphous polyester resin A, alicyclic diols, and trivalent or higher polyhydric diols. It may contain alcohol and the like.
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 10 mol% or more, more preferably 15 mol% or more, and preferably 90 mol% or less, more preferably 85 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 an aliphatic hydrocarbon group having 1 or more and 20 or less carbon atoms. Examples of the succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, and octenylsuccinic acid. Among these, adipic acid, fumaric acid, and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms are preferred.
The amount of linear or branched aliphatic dicarboxylic acid in the carboxylic acid component is preferably 90 mol% or less, more preferably 85 mol% or less, preferably 3 mol% or more, more preferably 5 mol% or more, and even more preferably 8 mol%. % or more.

The polyhydric carboxylic acid having a valence of 3 or more is preferably a trivalent carboxylic acid, such as trimellitic acid. Preferred is 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% or more in the carboxylic acid component. , and preferably 30 mol% or less, more preferably 20 mol% or less, and even more preferably 15 mol% or less.
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.

Polyester resin B may be produced, for example, by step A in which an alcohol component and a carboxylic acid component are polycondensed.
Step A is the same as Step A described in the method for producing amorphous polyester resin A, and the preferred range is also the same.
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.

(Physical properties of amorphous polyester resin B)
The glass transition temperature of the amorphous polyester resin B is preferably 55° C. or higher, more preferably 56° C. or higher, and even more preferably 57° C. or higher, from the viewpoint of charging stability and obtaining high-quality images. The temperature is preferably 75°C or lower, more preferably 72°C or lower, even more preferably 70°C or lower.

The softening point of the amorphous polyester resin B is preferably 85°C or higher, more preferably 95°C or higher, even more preferably 100°C or higher, and from the viewpoint of further improving low-temperature fixability, preferably 145°C. The temperature is more preferably 135°C or lower, and even more preferably 125°C or lower.

The acid value of the amorphous polyester resin B is preferably 5 mgKOH/g or more, more preferably 10 mgKOH/g or more, even more preferably 15 mgKOH/g or more, and preferably 45 mgKOH/g or less, more preferably 40 mgKOH/g. /g or less, more preferably 35 mgKOH/g or less, even more preferably 30 mgKOH/g or less.
The softening point, glass transition temperature, and acid value of polyester resin B can be adjusted as appropriate depending on the type and amount of raw material monomers used, and manufacturing conditions such as reaction temperature, reaction time, and cooling rate. The value of is determined by the method described in Examples.
In addition, when using a combination of two or more types of polyester resins B, 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.

The content of the polyester resin B is preferably 60% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and even more preferably 95% by mass, based on the total amount of resin components of the resin particles Y. % or more and 100% by mass or less, more preferably 100% by mass.

(Preparation of resin particle Y dispersion)
The resin particles Y are preferably produced by a method in which a resin component containing the polyester resin B and optional components such as a surfactant are dispersed in an aqueous medium to obtain a resin particle Y dispersion. .
The method for obtaining the resin particle Y dispersion is exemplified by the same method as in the case of the resin particle dispersion of resin particles It is preferable to obtain a resin particle Y dispersion.
As a phase inversion emulsification method, as in the case of resin particles preferable. Preferred embodiments of the aqueous medium and organic solvent that can be used are the same as the aqueous medium and organic solvent used for producing the resin particles X. In addition, in the phase inversion emulsification method, the preferred ranges of the mass ratio of the polyester resin B and the organic solvent, the degree of neutralization of the polyester resin B, the amount of the aqueous medium to be added, the mixing temperature, etc. are the same as in the production of the resin particles X. It is.

The solid content concentration of the resulting resin particle Y dispersion is preferably 7% by mass or more, more preferably 10% by mass or more, from the viewpoint of improving toner productivity and improving the dispersion stability of resin particles Y. It is more preferably 15% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less. Note that the solid content is the total amount of nonvolatile components such as resin and surfactant.

The volume median particle diameter (D ₅₀ ) of the resin particles Y in the resin particle Y dispersion is preferably 0.04 μm or more, more preferably 0.06 μm or more, from the viewpoint of obtaining a toner that can produce high-quality images. More preferably, it is 0.08 μm or more, and preferably 0.5 μm or less, more preferably 0.3 μm or less, even more preferably 0.2 μm or less, and still more preferably 0.15 μm or less.

In addition, the coefficient of variation (CV value) (%) of the particle size distribution of the resin particles Y is preferably 5% or more, more preferably 10% or more, and even more preferably is 15% or more, and is preferably 50% or less, more preferably 40% or less, still more preferably 30% or less, and even more preferably 25% or less, from the viewpoint of obtaining a toner that can produce high-quality images.
The volume median particle diameter (D ₅₀ ) and coefficient of variation (CV value) of the resin particles Y are measured by the method described in the Examples.

(Manufacture of aggregated particles 2)
In step 2, it is preferable to add a resin particle Y dispersion to the above-mentioned dispersion of aggregated particles 1 to further aggregate resin particles Y to the aggregated particles 1 to obtain a dispersion of aggregated particles 2.

Before adding the resin particle Y dispersion to the aggregated particle 1 dispersion, an aqueous medium may be added to the aggregated particle 1 dispersion to dilute it. Furthermore, when adding the resin particle Y dispersion to the aggregated particle 1 dispersion, the aggregating agent may be used in this step in order to efficiently adhere and aggregate the resin particles Y to the aggregated particles 1.
The temperature at which the resin particle Y dispersion is added is preferably 40° C. or higher, more preferably 45° C. or higher, and even more preferably 50° C. or higher, from the viewpoint of toner chargeability and high image quality. is 80°C or lower, more preferably 70°C or lower, even more preferably 60°C or lower.

The resin particle Y dispersion may be added continuously over a certain period of time, may be added all at once, or may be added in multiple portions, but it may be added continuously over a certain period of time. It is preferable to add the compound simultaneously or in multiple portions. Addition as described above makes it easier for the resin particles Y to selectively adhere to and aggregate on the aggregated particles 1. Among these, from the viewpoint of promoting selective adhesion and improving the productivity of toner, it is preferable to add it continuously over a certain period of time. The time for continuous addition is preferably 1 hour or more, more preferably 1.5 hours or more, from the viewpoint of obtaining uniform agglomerated particles 2 and improving toner productivity. The time is 10 hours or less, more preferably 7 hours or less, even more preferably 3 hours or less.

The amount of resin particles Y to be added is such that the mass ratio between resin particles Y and resin particles X (resin particles Y/resin particles X) is preferably 0.05 or more, and more Preferably 0.1 or more, more preferably 0.15 or more, and preferably 0.9 or less, more preferably 0.5 or less, still more preferably 0.3 or less, still more preferably 0.25 or less. This is the amount.

The volume median particle diameter (D ₅₀ ) of the obtained aggregated particles 2 is preferably 2 μm from the viewpoint of obtaining a toner that provides a high-quality image, and from the viewpoint of low-temperature fixability, charging property, and high image quality of the toner. Above, it is more preferably 3 μm or more, still more preferably 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less, still more preferably 7 μm or less.

<Step 3>
Step 3 is a step of adding a naphthalenesulfonic acid formalin condensate to the aggregated particles 2 at a temperature below the melting point of the crystalline polyester resin C.
In step 3, the temperature at which the naphthalene sulfonic acid formalin condensate is added is below the melting point of the crystalline polyester resin C, preferably below the melting point -5°C, more preferably below the melting point -10°C, even more preferably below the melting point -15°C. below ℃.
The naphthalene sulfonic acid formalin condensate is added for the purpose of improving the dispersion stability of aggregated particles during fusion. Although the naphthalene sulfonic acid formalin condensate may be present during aggregation in Step 1, it is newly added in Step 3 before fusion.
[Naphthalenesulfonic acid formalin condensate]
The naphthalene sulfonic acid formalin condensate is an amphiphilic molecule with a surfactant effect, and the naphthalene sulfonic acid is preferably an anionic surfactant, which is a naphthalene sulfonate.
The naphthalene sulfonic acid formalin condensate is a condensate of naphthalene sulfonic acid and formalin, and the naphthalene sulfonic acid is preferably a naphthalene sulfonate, and the naphthalene ring is substituted with a group other than a sulfonic acid group (sulfonic acid group). It may have a group.
The naphthalene sulfonic acid formalin condensate is preferably a compound represented by the following formula (1).

In formula (1), n preferably represents an integer of 2 or more and 200 or less, more preferably 6 or more and 100 or less, still more preferably 10 or more and 50 or less.
M each independently represents a cation, and examples include cations of elements selected from Group 1 elements and Group 2 elements of the periodic table of elements; quaternary ammonium; and ammonium (NH ₄ ⁺ ). Among these, cations of Group 1 elements of the periodic table of elements are preferred; cations of elements selected from lithium, sodium, and potassium are more preferred, and sodium cations are even more preferred. Moreover, it is preferable that a plurality of M's are the same cation.
R represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a hydroxyl group, and is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms from the viewpoint of improving heat-resistant storage stability.
The substitution position of -SO ₃ M is not particularly limited, and it may be substituted at the α position or β position of the naphthalene ring, but from the viewpoint of stabilizing the dispersion of aggregated particles, it is preferable to substitute it at the β position. It is preferable that there be.
In addition, some other structural units may be included within a range that does not impair the effect as a dispersion stabilizer. Other structural units include copolymerized alkylnaphthalenesulfonic acid, alkyl alcohol naphthalenesulfonic acid, etc. Examples of structural units formed from possible monomers are given below. The content of these structural units is preferably 30% by mass or less.
As the naphthalene sulfonic acid formalin condensate, β-naphthalene sulfonic acid formalin condensate sodium salt is preferred.

The weight average molecular weight of the naphthalene sulfonic acid formalin condensate is preferably 500 or more, more preferably 1,500 or more, still more preferably 2,500 or more, from the viewpoint of improving chargeability and heat-resistant storage stability. It is 40,000 or less, more preferably 20,000 or less, even more preferably 10,000 or less.
The weight average molecular weight of the naphthalene sulfonic acid formalin condensate is measured by GPC.

The naphthalene sulfonic acid formalin condensate can be produced by a known method, for example, by polycondensation using β-naphthalene sulfonic acid (salt), an equivalent amount of formalin, and other components as necessary. Examples of other components include sulfonic acids (salts) such as β-methylnaphthalene, α-methylnaphthalene, acenaphthene, dibenzofuran, fluorene, phenanthrene, anthracene, fluoranthene, and pyrene.
As the naphthalene sulfonic acid formalin condensate, commercially available products may be used, such as Demol N, Demol NL, Demol RN, Demol RN-L, Demol T, Demol T-45, and Demol manufactured by Kao Corporation. MS, Demol SN-B, Demol SS-L, Demol SC-30, Lavelin AN-40 manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Lavelin FN-P, Lavelin MN-P, Lavelin F-45, Lavelin FC-45, Examples include Lavelin FC-P, Lavelin FD-40, Lavelin FP, and Ionet D-2 manufactured by Sanyo Chemical Industries, Ltd.

The amount of the naphthalene sulfonic acid formalin condensate added in step 3 is preferably 0.5 parts by mass or more, more preferably 1 part by mass, based on 100 parts by mass of the resin component in the aggregated particles 2, from the viewpoint of obtaining high-quality images. parts or more, more preferably 3 parts by mass or more, and preferably 30 parts by mass or less, more preferably 20 parts by mass or less, still more preferably 10 parts by mass or less.

<Step 4>
Step 4 is a step of fusing the aggregated particles 2 at a temperature higher than the glass transition temperature of the amorphous polyester resin B and higher than the melting point of the crystalline polyester resin C by -10° C. to obtain toner particles.
The heating temperature in step 4 is at least the glass transition temperature of the amorphous polyester resin B, preferably at least 2°C higher, from the viewpoint of improving the fusion properties of the aggregated particles and the productivity of the toner. , more preferably at least 4°C higher, still more preferably at least 5°C higher, and preferably at most 30°C higher, more preferably 25°C higher than the glass transition temperature of the amorphous polyester resin B. The temperature is below the temperature, more preferably below the temperature which is 20°C higher.

The heating temperature in step 4 is a temperature equal to or higher than the melting point of the crystalline polyester resin C by -10°C, preferably -6°C from the viewpoint of improving the fusing properties of the aggregated particles and the productivity of the toner. As mentioned above, the melting point is more preferably −3° C. or higher, and preferably the melting point of the crystalline polyester resin C is +5° C. or lower, more preferably the melting point +3° C. or lower, and even more preferably the melting point or lower.

The time for holding at the above heating temperature is preferably 1 minute or more, more preferably 10 minutes or more, still more preferably 30 minutes or more, and preferably 240 minutes, from the viewpoint of toner chargeability and high image quality. The duration is more preferably 180 minutes or less, still more preferably 120 minutes or less, and even more preferably 90 minutes or less.
Note that it is preferable to maintain the above temperature until a desired degree of circularity is achieved.

The volume median particle diameter (D ₅₀ ) of the toner particles (core-shell particles) obtained in step 4 is preferably 2 μm or more, more preferably 3.5 μm or more, and even more preferably 5 μm or more, from the viewpoint of obtaining high-quality images. and is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 7 μm or less.
Note that the volume median particle size of the toner particles (core-shell particles) obtained in step 4 is preferably equal to or smaller than the volume median particle size of the aggregated particles 2. That is, in this step 4, it is preferable that the agglomerated particles 2 do not aggregate or fuse together.

<Post-processing process>
In the present invention, a post-treatment step may be performed after step 4, and toner particles are preferably obtained by isolation.
Since the core-shell particles obtained in step 4 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, it is preferable to also remove the added surfactant, so if the surfactant has a cloud point, it is preferable to wash with an aqueous medium at a temperature below the cloud point of the surfactant. It is preferable to perform washing multiple times.

Next, drying is preferably performed. The temperature during drying is preferably such that the temperature of the core-shell particles themselves is lower than the glass transition temperature of the amorphous polyester resin A, more preferably 10° C. or more lower. As the drying method, it is preferable to use a vacuum low temperature drying method, a vibration type fluidized drying method, a spray drying method, a freeze drying method, a flash jet method, or the like.

(toner particles)
Although the toner particles obtained by drying etc. can be used as they are as a toner for developing an electrostatic image, it is preferable to use the toner particles whose surface has been treated as described below as a toner for developing an electrostatic image. .
The volume median particle diameter (D ₅₀ ) of the toner particles is preferably 2 μm or more, more preferably 3 μm or more, and even more preferably It is 4 μm or more, and preferably 10 μm or less, more preferably 8 μm or less, and still more preferably 6.5 μm or less.
The circularity of the toner particles is preferably 0.955 or more, more preferably 0.960 or more, still more preferably 0.965 or more, and preferably 0.955 or more, from the viewpoint of toner chargeability and high image quality. It is 990 or less, more preferably 0.985 or less, even more preferably 0.980 or less.

(external additive)
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.
Examples of external additives include hydrophobic silica, titanium oxide particles, alumina particles, cerium oxide particles, inorganic particles such as carbon black, and polymer particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Polysilica is preferred.
The external additives may be used alone or in combination of two or more. Further, external additives of the same type having different particle sizes may be used together.
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 4.0 parts by weight or less.

[Toner for developing electrostatic images]
The electrostatic image developing toner obtained according to the present invention can be used as a one-component developer, or mixed with a carrier and used as a two-component developer.

The present invention further discloses the following [1] to [17].
[1] A method for producing a toner for developing an electrostatic image, comprising the following steps 1 to 4 in this order, wherein the amorphous polyester resin B contains 50 mol % or more of an ethylene oxide adduct of bisphenol A as an alcohol component.
Step 1: Step of mixing and agglomerating polyester resin particles X containing crystalline polyester resin C and amorphous polyester resin A and colorant particles in an aqueous medium to obtain aggregated particles 1 Step 2: Step Step 3: Agglomerated particles 1 obtained in step 1 are aggregated with resin particles Y containing amorphous polyester resin B to obtain aggregated particles 2. Step 3: At a temperature below the melting point of crystalline polyester resin C. Step 4: Adding a naphthalene sulfonic acid formalin condensate to the aggregated particles 2. Step 4: Adding the aggregated particles to the aggregated particles 2 at a temperature higher than the glass transition temperature of the amorphous polyester resin B and higher than the melting point of the crystalline polyester resin C by -10°C. [2] The amorphous polyester resin A contains a bisphenol A propylene oxide adduct as an alcohol component, preferably at least 50 mol%, more preferably at least 60 mol%, even more preferably The method for producing an electrostatic image developing toner according to [1], wherein the toner contains 70 mol% or more, more preferably 90 mol% or more, even more preferably 100 mol%.
[3] The amorphous polyester resin A contains a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component, and an addition polymer resin segment that is an addition polymer of a raw material monomer containing a styrene compound. The method for producing an electrostatic image developing toner according to [1] or [2].
[4] The toner for developing electrostatic images according to any one of [1] to [3], wherein the amorphous polyester resin B is a polyester resin that is a polycondensate of an alcohol component and a carboxylic acid component. Production method.
[5] The amorphous polyester resin B contains an ethylene oxide adduct of bisphenol as an alcohol component, preferably at least 60 mol%, more preferably at least 80 mol%, even more preferably at least 90 mol%, even more preferably 100 mol%. , the method for producing an electrostatic image developing toner according to any one of [1] to [4].
[6] In the ethylene oxide adduct of bisphenol that the amorphous polyester resin B contains as an alcohol component, the average number of added moles of ethylene oxide is 1 or more, preferably 1.5 or more, more preferably 1.8 or more. The electrostatic charge according to any one of [1] to [5], which is preferably 16 or less, more preferably 8 or less, still more preferably 4 or less, still more preferably 3 or less, even more preferably 2.5 or less. A method for producing toner for image development.

[7] The glass transition temperature of the amorphous polyester resin B is preferably 55°C or higher, more preferably 56°C or higher, even more preferably 57°C or higher, and preferably 75°C or lower, more preferably The method for producing a toner for developing an electrostatic image according to any one of [1] to [6], wherein the temperature is 72°C or lower, more preferably 70°C or lower.
[8] The softening point of the amorphous polyester resin B is preferably 85°C or higher, more preferably 95°C or higher, even more preferably 100°C or higher, and preferably 145°C or lower, more preferably 135°C or higher. The method for producing an electrostatic image developing toner according to any one of [1] to [7], wherein the temperature is 125° C. or lower, more preferably 125° C. or lower.
[9] The mass ratio of resin particles Y and resin particles X (resin particles Y/resin particles X) is preferably 0.05 or more, more preferably 0.1 or more, and still more preferably 0.15 or more, and the amount is preferably 0.9 or less, more preferably 0.5 or less, even more preferably 0.3 or less, even more preferably 0.25 or less, according to any one of [1] to [8]. A method for producing a toner for developing an electrostatic image.
[10] The method for producing a toner for developing an electrostatic image according to any one of [1] to [9], wherein the crystalline polyester resin C has a melting point of 50° C. or more and 100° C. or less.
[11] In step 3, the temperature at which the naphthalene sulfonic acid formalin condensate is added is preferably below the melting point of the crystalline polyester resin C -5°C, more preferably below the melting point -10°C, even more preferably below the melting point -15°C. The method for producing an electrostatic image developing toner according to any one of [1] to [10] below.
[12] The method for producing an electrostatic image developing toner according to any one of [1] to [11], wherein the naphthalene sulfonic acid formalin condensate is a compound represented by the following formula (1).

In formula (1), n preferably represents an integer of 2 or more and 200 or less, more preferably 6 or more and 100 or less, still more preferably 10 or more and 50 or less, and M each independently represents a cation, Examples include cations of elements selected from Group 1 elements and Group 2 elements; quaternary ammonium; and ammonium (NH ₄ ⁺ ), among which cations of Group 1 elements of the periodic table of elements are Preferably; a cation of an element selected from lithium, sodium, and potassium is more preferable, a cation of sodium is even more preferable, and it is preferable that the plurality of M's are the same cation, R is a hydrogen atom, and a carbon number of 1 or more It represents an alkyl group of 6 or less or a hydroxyl group, and from the viewpoint of improving heat-resistant storage stability, it is preferably a hydrogen atom or an alkyl group having 1 or more and 6 or less carbon atoms, and the substitution position of -SO ₃ M is not particularly limited, It may be substituted at the α-position of the naphthalene ring, or it may be substituted at the β-position, but from the viewpoint of stabilizing the dispersion of aggregated particles, it is preferably at the β-position, which impairs the effect as a dispersion stabilizer. It may partially contain other structural units to the extent that it is not, and other structural units include a structure formed from copolymerizable monomers such as alkylnaphthalene sulfonic acid and alkyl alcohol naphthalene sulfonic acid. The units are exemplified, and the content of these structural units is preferably 30% by mass or less.

[12] The method for producing a toner for developing an electrostatic image according to any one of [1] to [11], wherein the naphthalene sulfonic acid formalin condensate is a β-naphthalene sulfonic acid formalin condensate sodium salt.
[13] The weight average molecular weight of the naphthalene sulfonic acid formalin condensate is preferably 500 or more, more preferably 1,500 or more, even more preferably 2,500 or more, and preferably 40,000 or less, more preferably is 20,000 or less, more preferably 10,000 or less, the method for producing a toner for developing an electrostatic image according to any one of [1] to [12].
[14] The amount of the naphthalene sulfonic acid formalin condensate added in step 3 is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and even more preferably is 3 parts by mass or more, and preferably 30 parts by mass or less, more preferably 20 parts by mass or less, still more preferably 10 parts by mass or less, the electrostatic charge according to any one of [1] to [13]. A method for producing toner for image development.
[15] The heating temperature in step 4 is preferably at least 2°C higher than the glass transition temperature of the amorphous polyester resin B, more preferably at least 4°C higher, even more preferably at least 5°C higher. , and the glass transition temperature of the amorphous polyester resin B is preferably 30°C higher or lower, more preferably 25°C higher or lower, still more preferably 20°C higher or lower, [1] to [14] ] The method for producing a toner for developing an electrostatic image according to any one of the above.
[16] The heating temperature in step 4 is preferably at least -10°C, the melting point of the crystalline polyester resin C, preferably at least -6°C, more preferably at least -3°C, and preferably The method for producing an electrostatic image developing toner according to any one of [1] to [15], wherein the melting point of the crystalline polyester resin C is +5° C. or lower, more preferably the melting point +3° C. or lower, and even more preferably the melting point or lower.
[17] The volume median particle diameter (D ₅₀ ) of the toner particles obtained in step 4 is preferably 2 μm or more, more preferably 3.5 μm or more, even more preferably 5 μm or more, and preferably 10 μm or less. , more preferably 8 μm or less, still more preferably 7 μm or less, the method for producing a toner for developing an electrostatic image according to any one of [1] to [16].

The present invention will be explained in more detail below using Examples. In the Examples below, each physical property was measured and evaluated by the following method. In addition, in the following examples, room temperature is a temperature of 20°C or more and 25°C or less.

[Measuring method]
<Acid value of resin>
The acid value of the resin was measured according to JIS K0070:1992. However, the measurement solvent was a mixed solvent of acetone and toluene [acetone:toluene=1:1 (volume ratio)].

<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 "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 g of the sample was weighed into an aluminum pan, and the temperature was lowered to 0°C at a cooling rate of 10°C/min. Cooled to . 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 "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 g of the sample was weighed into an aluminum pan, and the temperature was raised to 200°C. It was cooled from that temperature to 0°C at a cooling rate of 10°C/min. Thereafter, the temperature was increased at a rate of 10° C./min, and the amount of heat was measured. Among the observed endothermic peaks, the peak temperature with the largest peak area was defined as the maximum endothermic peak temperature (2). In the case of crystalline polyester resin, this peak temperature was taken as the melting point. In the case of an amorphous resin, the glass transition temperature was defined as the temperature at the intersection of the extension line of the baseline below the maximum endothermic peak temperature and the tangent line showing the maximum slope from the rising part of the peak to the apex of the peak.

<Weight average molecular weight of addition polymer>
Using a solution prepared by dissolving phosphoric acid and lithium bromide in N,N-dimethylformamide to a concentration of 60 mmol/L and 50 mmol/L, respectively, as an eluent, a gel permeation chromatography method [GPC device "HLC-8320GPC"] was performed. (manufactured by Tosoh Corporation), column "TSKgel SuperAWM-H", "TSKgel SuperAW3000", "TSKgel guardcolumn Super AW-H" (manufactured by Tosoh Corporation), flow rate: 0.5 mL/min], the molecular weight is known as a standard substance. Monodisperse polystyrene kit [PStQuick B (F-550, F-80, F-10, F-1, A-1000), PStQuick C (F-288, F-40, F-4, A-5000, A -500), manufactured by Tosoh Corporation].

<Melting point of mold release agent>
Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 g of the sample was weighed into an aluminum pan, heated to 200°C, and then cooled at a cooling rate of 10°C from 200°C. /min 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 (D ₅₀ ) and CV value of resin particles, release agent particles, and colorant 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 were measured at a temperature that brought the absorbance to 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 size) x 100

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

<Volume median particle diameter (D ₅₀ ) of aggregated particles>
The volume median particle diameter (D ₅₀ ) 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 (D ₅₀ ) was determined from the distribution.

<Circularity of toner particles (fused particles)>
The circularity of toner particles (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 toner particles was prepared by diluting it with deionized water so that the solid content concentration was 0.001% by mass or more and 0.05% by mass or less.
・Measurement mode: HPF measurement mode

<Volume median particle diameter (D ₅₀ ) of toner particles>
The volume median particle diameter (D ₅₀ ) 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 (D ₅₀ ) 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 the measurement sample of toner particles after drying to 5 mL of the above dispersion liquid, disperse for 1 minute with an ultrasonic disperser, then add 25 mL of electrolyte, and further disperse with an ultrasonic disperser. A sample dispersion liquid was prepared by dispersing for 1 minute.
・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 ) was determined from the distribution.

[Toner evaluation method]
<Evaluation of image quality (fog)>
Toner was installed in a commercially available printer "Microline (registered trademark) 5400" (manufactured by Oki Data Co., Ltd.), and high-quality paper "J paper A4 size" (manufactured by Fuji Xerox Co., Ltd.) was printed in an environment of 25 degrees Celsius and 60% humidity. An image with a print density of 1% was printed on. After repeating this process and printing a total of 1000 sheets, blank paper printing was performed next, and at this time, the printer was stopped in the middle of blank paper printing. The developing unit was taken out from the printer, and "Scotch (registered trademark) mending tape 810" (manufactured by 3M Japan Ltd., width: 18 mm) was pasted on the photoreceptor, and the toner on the photoreceptor was peeled off with the tape.
Paste the tape peeled from the photoreceptor and the unused tape on high-quality paper "J Paper A4 size" (manufactured by Fuji Xerox Co., Ltd.), and measure the tape peeled from the photoreceptor and the unused tape with a colorimeter. SpectroEye" (manufactured by Gretag Macbeth, light irradiation conditions: standard light source D50, observation field of view 2°, density standard DINNB, absolute white standard). The color difference (ΔE) between the tape peeled off from the photoreceptor and the unused tape was defined as fog. The smaller the fog value is, the better the image is without fog.

<Toner chargeability evaluation>
Similar to the image quality fog evaluation, toner was installed in a commercially available printer "Microline (registered trademark) 5400" (manufactured by Oki Data Co., Ltd.), and high-quality paper "J paper A4 size" was installed in an environment of 25 degrees Celsius and 60% humidity. (manufactured by Fuji Xerox Co., Ltd.) with an image density of 1%. After repeating this process and printing a total of 1000 sheets, the next solid image is printed on Excellent White paper (Oki Data Co., Ltd. 80g/ ^m2 paper), and when half of the A4 paper has been transferred, the machine is stopped and developed. A 1 cm x 2 cm jig was attached to a portion 3 cm from both ends of the roller, and the amount of charge was measured using a Q/m meter "210HS" (manufactured by Trek). The chargeability is negatively chargeable, and the higher the absolute value of the charge amount, the higher the chargeability.

[Production of resin]
Production Example A1 (Production of amorphous polyester resin A-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 3395 g of propylene oxide (2.2) adduct of bisphenol A, 853 g of terephthalic acid, and Add 25 g of tin (II) (2-ethylhexanoic acid) and 3 g of gallic acid (3,4,5-trihydroxybenzoic acid), and raise the temperature to 235°C with stirring under a nitrogen atmosphere. After holding for 8 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 2326 g of styrene, 581 g of stearyl methacrylate, 112 g of acrylic acid, and 323 g of dibutyl peroxide was added dropwise over 3 hours. 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 temperature was maintained at 8 kPa for 1 hour. Then, after returning to atmospheric pressure, it was cooled to 190°C, 180g of fumaric acid, 294g of sebacic acid, 186g of trimellitic acid anhydride, and 1.8g of 4-tert-butylcatechol were added, and the temperature was increased to 210°C at 10°C/hr. After that, the reaction was carried out at 4 kPa to a desired softening point to obtain amorphous polyester resin A-1. Various physical properties of the resin were measured and shown in Table 1.

Production example B1 (production of amorphous polyester resin B-1)
The inside of a 10 L four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 5330 g of ethylene oxide (2.2) adduct of bisphenol A, 2178 g of terephthalic acid, and dodecenyl succinic acid were added. Add 220 g of anhydride, 120 g of adipic acid, 40 g of tin(II) di(2-ethylhexanoate), and 4 g of gallic acid, and raise the temperature to 235°C with stirring under a nitrogen atmosphere, and hold at 235°C for 10 hours. After that, the pressure inside the flask was lowered and maintained at 8 kPa for 1 hour. Thereafter, 315 g of trimellitic anhydride was added, and the mixture was further maintained at 230° C. for 3 hours. Thereafter, the pressure inside the flask was lowered and the reaction was carried out at 10 kPa to a desired softening point to obtain amorphous polyester resin B-1. Various physical properties of the resin were measured and shown in Table 1.

Production example B2 (production of amorphous polyester resin B-2)
The inside of a 10 L four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 5850 g of ethylene oxide (2.2) adduct of bisphenol A, 538 g of terephthalic acid, and di( Add 40 g of tin(II) (2-ethylhexanoate) and 4 g of gallic acid, raise the temperature to 235°C while stirring under a nitrogen atmosphere, hold it at 235°C for 5 hours, then lower the pressure inside the flask. It was maintained at 8 kPa for 1 hour. Then, after returning to atmospheric pressure, it was cooled to 180°C, 1712 g of fumaric acid and 17 g of 4-tert-butylcatechol were added, and the temperature was raised to 220°C at a rate of 10°C/hr, and then the pressure inside the flask was lowered. , 10 kPa to a desired softening point to obtain amorphous polyester resin B-2. Various physical properties of the resin were measured and shown in Table 1.

Production example B3 (production of amorphous polyester resin B-3)
The inside of a 10 L four-necked flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 1628 g of propylene oxide (2.2) adduct of bisphenol A and ethylene oxide of bisphenol A ( 2.2) Add 3,526 g of the adduct, 2,058 g of terephthalic acid, 415 g of dodecenylsuccinic anhydride, 40 g of tin(II) di(2-ethylhexanoate), and 4 g of gallic acid, and heat to 235°C while stirring under nitrogen atmosphere. After raising the temperature and keeping it at 235°C for 11 hours, the pressure inside the flask was lowered and kept at 8 kPa for 1 hour. Thereafter, 298 g of trimellitic anhydride was added, and the mixture was further maintained at 230° C. for 3 hours. Thereafter, the pressure inside the flask was lowered and the reaction was carried out at 10 kPa to a desired softening point to obtain amorphous polyester resin B-3. Various physical properties of the resin were measured and shown in Table 1.

Production Example D1 (Production of amorphous polyester resin D-1)
The inside of a 10 L four-neck flask equipped with a nitrogen inlet tube, dehydration tube, stirrer, and thermocouple was replaced with nitrogen, and 4830 g of propylene oxide (2.2) adduct of bisphenol A, 916 g of terephthalic acid, and Add 33 g of tin (II) (2-ethylhexanoic acid) and 3 g of gallic acid (3,4,5-trihydroxybenzoic acid), and raise the temperature to 235°C with stirring under a nitrogen atmosphere. After holding for 5 hours, the pressure inside the flask was lowered and held at 8 kPa for 1 hour. After that, the pressure was returned to atmospheric pressure, the temperature was cooled to 160°C, and while the temperature was maintained at 160°C, a mixture of 1174 g of styrene, 258 g of 2-ethylhexyl acrylate, 79 g of acrylic acid, and 159 g of dibutyl peroxide was added dropwise over 3 hours. did. 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 temperature was maintained at 8 kPa for 1 hour. Then, after returning to atmospheric pressure, it was cooled to 190°C, 784 g of fumaric acid and 7.8 g of 4-tert-butylcatechol were added, and the temperature was raised to 210°C at a rate of 10°C/hr. The reaction was carried out to the softening point to obtain amorphous polyester resin D-1. Various physical properties of the resin were measured and shown in Table 1.

Production Example C1 (Production of crystalline polyester resin C-1)
The inside of a four-neck flask with an internal volume of 10 L equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was purged with nitrogen, and 3416 g of 1,10-decanediol and 4084 g of sebacic acid were charged. While stirring, the temperature was raised to 135°C, held at 135°C for 3 hours, and then raised from 135°C to 200°C over 10 hours. Thereafter, 23 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 at 8.3 kPa for 1 hour. C-1 was obtained. Various physical properties of the resin were measured and shown in Table 2.

Production example E1 (addition polymer E-1)
As raw material monomers, 44 g of styrene, 16 g of methacrylic acid, 15 g of styrene macromer AS-6S (manufactured by Toagosei Co., Ltd.), and 25 g of methoxypolyethylene glycol methacrylate (Blenmar PME-200, manufactured by NOF Corporation) were mixed, and the total amount of monomers was 100 g. A mixed solution was prepared.
The inside of a four-necked flask equipped with a nitrogen introduction tube, a dropping funnel, a stirrer, and a thermocouple was replaced with nitrogen, and 18 g of methyl ethyl ketone, 0.03 g of 2-mercaptoethanol, and 10% by mass of the monomer mixture were added, The temperature was raised to 75°C while stirring. While maintaining the temperature at 75°C, the remaining 90% by mass of the monomer mixture, 0.27g of 2-mercaptoethanol, 42g of methyl ethyl ketone and 2,2'-azobis(2,4-dimethylvaleronitrile) "V-65" (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) 3 g of a mixed solution was added dropwise from a dropping funnel over a period of 3 hours. After the dropwise addition was completed, the mixture was held at 75°C for 2 hours, and then a solution of 3 g of V-65 dissolved in 5 g of methyl ethyl ketone was added, and the mixture was further held at 75°C for 2 hours and at 80°C for 2 hours. Thereafter, methyl ethyl ketone was distilled off under reduced pressure to obtain addition polymer E-1. The weight average molecular weight of addition polymer E-1 was 5.0×10 ⁴ .

[Manufacture of resin particle dispersion]
Production Example X1 (Production of resin particle dispersion X-1)
In a container with an internal volume of 3 L equipped with a stirrer "Three-One Motor BL300" (manufactured by Shinto Kagaku Co., Ltd.), a reflux condenser, a dropping funnel, and a thermometer, 320 g of amorphous polyester resin A-1 and crystalline polyester were placed. 80 g of resin C-1 and 400 g of methyl ethyl ketone were added, and the resin was dissolved at 73° C. over 2 hours. A 5% by mass aqueous sodium hydroxide solution was added to the obtained solution so that the degree of neutralization was 50 mol% based on the acid value of the resin, and the mixture was stirred for 60 minutes.
Next, while maintaining the temperature at 73° C. and stirring at 200 r/min (peripheral speed 63 m/min), 800 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, and the solid content concentration was adjusted to 30% by mass by adding deionized water. After that, it was filtered through a 150 mesh wire mesh, and the resin particle dispersion I got -1. Table 3 shows the volume median particle diameter (D ₅₀ ) and CV value of the obtained resin particles.

Production examples X2 and Z1 (manufacture of resin particle dispersions X-2 and Z-1)
Resin particle dispersions X-2 and Z-1 were obtained in the same manner as Production Example X1, except that the combinations of amorphous polyester resin and crystalline polyester resin used were as shown in Table 3. Table 3 shows the volume median particle diameter (D ₅₀ ) and CV value of the obtained resin particles.

Production Example Y1 (Production of resin particle dispersion Y-1)
Put 200 g of amorphous polyester resin B-1 and 200 g of methyl ethyl ketone into a 2 L container equipped with a stirrer "Three-One Motor BL300" (manufactured by Shinto Kagaku Co., Ltd.), a reflux condenser, a dropping funnel, and a thermometer. The resin was dissolved at 40° C. for 2 hours. A 5 mass % sodium hydroxide aqueous solution was added to the obtained solution so that the degree of neutralization was 65 mol % with respect to the acid value of the resin, and the mixture was stirred for 60 minutes. Next, while maintaining the temperature at 40° C. and stirring at 200 r/min (peripheral speed 63 m/min), 400 g of deionized water was added over 60 minutes to effect phase inversion emulsification. The temperature was then raised to 73°C, and methyl ethyl ketone was distilled off under reduced pressure at 73°C to obtain an aqueous dispersion. After that, the aqueous dispersion was cooled to 30°C while stirring, and the solid content concentration was adjusted to 30% by mass by adding deionized water. After that, it was filtered through a 150 mesh wire mesh, and the resin particle dispersion Y I got -1. Table 3 shows the volume median particle diameter (D ₅₀ ) and CV value of the obtained resin particles.

Production examples Y2 and Y3 (manufacture of resin particle dispersions Y-2 and Y-3)
Resin particle dispersions Y-2 and Y-3 were obtained in the same manner as in Production Example Y1, except that the amorphous polyester resin B-1 was changed to the amorphous polyester resin shown in Table 3. Table 3 shows the volume median particle diameter (D ₅₀ ) and CV value of the obtained resin particles.

[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, add 120 g of deionized water, 53 g of resin particle dispersion Z-1, and 40 g of paraffin wax "HNP-9" (manufactured by Nippon Seiro Co., Ltd., melting point 75 °C), and heat the mixture to 90 °C or higher and 95 °C. The mixture was melted and stirred while maintaining the temperature below to obtain a molten mixture. While maintaining the temperature at 90° C. or higher and 95° C. or lower, dispersion treatment was performed for 20 minutes using an ultrasonic homogenizer “US-600T” (manufactured by Nippon Seiki Seisakusho Co., Ltd.), and then cooled to room temperature. Deionized water was added to the obtained dispersion to adjust the solid content concentration to 20% by mass to obtain a release agent particle dispersion W-1. The volume median particle diameter (D ₅₀ ) was 0.46 μm, and the CV value was 25%.

[Manufacture of colorant particle dispersion]
Production example P1 (production of colorant particle dispersion P-1)
Addition polymer E-1 (50 g) and methyl ethyl ketone (180.5 g) were added to a 2 L container to dissolve addition polymer E-1. To the obtained solution, 55.8 g of a 5% aqueous sodium hydroxide solution (an amount that would give a neutralization degree of addition polymer E-1 of 75%) was added, and further 243 g of deionized water was added to prepare a disper blade. The mixture was stirred for 10 minutes at 2,000 rpm/min using a stirrer "Labolution" (manufactured by Primix Co., Ltd.). Next, 200 g of a copper phthalocyanine pigment "ECB-301" (phthalocyanine blue, manufactured by Dainichiseika Industries, Ltd.) was added, and stirring was performed at 20° C. for 1 hour at 6,400 rpm/min. 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 removed under reduced pressure at 70°C. 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 P-1. The volume median particle diameter (D ₅₀ ) of the colorant particles in the dispersion was 0.14 μm, and the CV value was 25%.

[Manufacture of toner]
Example 1 (Preparation of toner 1)
In a 4-neck flask with an internal volume of 3 L equipped with a dehydration tube, a stirring device, and a thermocouple, 300 g of resin particle dispersion X-1, 52.9 g of release agent particle dispersion W-1, and colorant particle dispersion were added. 75.6 g of P-1 and 126.2 g of deionized water were mixed at room temperature. Next, while stirring the mixture, 32.5 g of a 4.8% by mass potassium hydroxide aqueous solution was added to an aqueous solution of 37.5 g of ammonium sulfate dissolved in 549.3 g of deionized water to adjust the pH to 8.5. , was added dropwise at room temperature over 15 minutes. Thereafter, the temperature was raised to 62° C. over 2 hours and maintained at 62° C. until the volume median particle diameter (D ₅₀ ) of the aggregated particles became 5.9 μm, to obtain a dispersion of aggregated particles 1.
This aggregated particle dispersion was cooled to 54°C, and while being maintained at 54°C, a mixed solution of 60.0 g of resin particle dispersion Y-1 and 18.3 g of deionized water was added over 120 minutes, and the resin was added to the aggregated particles. An aggregated particle dispersion in which particles Y-1 were aggregated and had a volume median particle diameter (D ₅₀ ) of 6.2 μm was obtained.
18.6 g of a 30% aqueous solution of the anionic surfactant "Demol N" (manufactured by Kao Corporation, β-naphthalene sulfonic acid formalin condensate sodium salt) and 1280.4 g of deionized water were added to the 54° C. aggregated particle dispersion. A mixed aqueous solution was added. Thereafter, the temperature was raised to 75°C over 1 hour, and after reaching 75°C, 140.3 g of 0.1 mol/L sulfuric acid was added. The circularity was measured while maintaining the temperature at 75°C, and by holding the temperature at 75°C until the circularity reached a range of 0.965 or more and 0.975 or less, the volume median particle size of the aggregated particles was 6. A 0 μm fused particle dispersion was obtained.
The resulting dispersion of fused particles was cooled to 30°C, filtered under suction to separate the solid content, washed with deionized water at 25°C, and vacuum dried at 30°C for 48 hours to form toner particles. I got it. The volume median particle diameter (D ₅₀ ) and CV value of the obtained toner particles were measured. 100 parts by mass of the 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" (Cabot Japan) Co., Ltd., number average particle size: 0.012 μm) was placed in a Henschel mixer, stirred, and passed through a 150 mesh sieve to obtain Toner 1.

Example 2 (manufacture of toner 2)
In Example 1, after mixing resin particle dispersion X-1, release agent particle dispersion W-1, colorant particle dispersion P-1, and deionized water at room temperature, anionic surfactant "Demol" After adding and mixing 3.0 g of a 30% aqueous solution of "N" (manufactured by Kao Corporation, β-naphthalenesulfonic acid formalin condensate sodium salt), ammonium sulfate, deionized water, and potassium hydroxide aqueous solution were added dropwise with stirring. Toner 2 was obtained in the same manner except for that.

Example 3 (manufacture of toner 3)
In Example 1, the anionic surfactant "Demol N" (manufactured by Kao Corporation, β-naphthalene sulfonic acid formalin condensate sodium salt) was substituted with the anionic surfactant "Demol MS" (manufactured by Kao Corporation, methylnaphthalene condensate). Toner 3 was obtained in the same manner except that sulfonic acid formalin condensate sodium salt was used.

Example 4 (manufacture of toner 4)
In Example 1, after obtaining an aggregated particle dispersion in which resin particles Y-1 were aggregated into aggregated particles, the aggregated particle dispersion was cooled to 30°C, and then a 30% aqueous solution of the anionic surfactant "Demol N" was added. Toner 4 was obtained in the same manner except that an aqueous solution containing deionized water was added.

Examples 5, 6, and 7 (manufacture of toners 5, 6, and 7)
Toners 5, 6, and 7 were obtained in the same manner as in Example 1, except that the resin particle dispersion shown in Table 4 was used.

Comparative example 1 (manufacture of toner 91)
In Example 1, after mixing resin particle dispersion X-1, release agent particle dispersion W-1, colorant particle dispersion P-1, and deionized water at room temperature, anionic surfactant "Demol" After adding and mixing 3.0 g of a 30% aqueous solution of "N" (manufactured by Kao Corporation, β-naphthalenesulfonic acid formalin condensate sodium salt), ammonium sulfate, deionized water, and potassium hydroxide aqueous solution were added dropwise with stirring. The aggregation step was carried out in the same manner except for that. After obtaining an aggregated particle dispersion in which resin particles Y-1 aggregated with aggregated particles, only deionized water was added without adding the anionic surfactant "Demol N", and the temperature was raised to 75°C in 1 hour. As a result, coarse fused particles were obtained, and since it was difficult to measure the particle size using the method described above, the volume median particle size exceeded 20 μm, and no toner could be obtained.

Comparative example 2 (manufacture of toner 92)
In Example 1, after mixing resin particle dispersion X-1, release agent particle dispersion W-1, colorant particle dispersion P-1, and deionized water at room temperature, anionic surfactant "Demol" After adding and mixing 3.0 g of a 30% aqueous solution of "N" (manufactured by Kao Corporation, β-naphthalenesulfonic acid formalin condensate sodium salt), ammonium sulfate, deionized water, and potassium hydroxide aqueous solution were added dropwise with stirring. The aggregation step was carried out in the same manner except for that. After obtaining an agglomerated particle dispersion in which resin particles Y-1 agglomerated into agglomerated particles, the anionic surfactant "Emar (registered trademark) E-27C" (Kao Corporation) was used instead of the anionic surfactant "Demol N". Toner 92 was obtained in the same manner except that 20 g of sodium polyoxyethylene lauryl ether sulfate (effective concentration: 27% by mass) manufactured by the company was used.

Comparative example 3 (manufacture of toner 93)
The same procedure as in Example 1 was carried out except that resin particles Y-1 were added to the aggregated particles at 54° C. to obtain an aggregated particle dispersion in which the resin particles Y-1 were aggregated to the aggregated particles. After that, an aqueous solution mixed with 1280.4 g of deionized water was added, and the temperature was raised to 80° C. over 1 hour. After reaching 80° C., 18.6 g of a 30% aqueous solution of anionic surfactant “Demol N” was added. When the particle size was measured after addition, it was found to be coarse fused particles, and since it was difficult to measure the particle size using the method described above, the volume median particle size exceeded 20 μm and no toner could be obtained. .

From the results of the Examples and Comparative Examples above, it can be seen that according to the present invention, a toner with excellent chargeability and image quality can be obtained.

Claims (6)

Including the following steps 1 to 4 in this order,
Amorphous polyester resin B contains 50 mol% or more of an ethylene oxide adduct of bisphenol A as an alcohol component,
A method for producing a toner for developing electrostatic images.
Step 1: Step of mixing and agglomerating polyester resin particles X containing crystalline polyester resin C and amorphous polyester resin A and colorant particles in an aqueous medium to obtain aggregated particles 1 Step 2: Step Step 3: Agglomerated particles 1 obtained in step 1 are aggregated with resin particles Y containing amorphous polyester resin B to obtain aggregated particles 2. Step 3: At a temperature below the melting point of crystalline polyester resin C. Step 4: Adding a naphthalene sulfonic acid formalin condensate to the aggregated particles 2. Step 4: Adding the aggregated particles to the aggregated particles 2 at a temperature higher than the glass transition temperature of the amorphous polyester resin B and higher than the melting point of the crystalline polyester resin C by -10°C. 2 to obtain toner particles 2. The method for producing a toner for developing an electrostatic image according to claim 1, wherein the amorphous polyester resin A contains 50 mol% or more of a bisphenol A propylene oxide adduct as an alcohol component. A claim in which the amorphous polyester resin A contains a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component, and an addition polymer resin segment that is an addition polymer of a raw material monomer containing a styrene compound. Item 2. A method for producing an electrostatic image developing toner according to item 1 or 2. The method for producing a toner for developing an electrostatic image according to any one of claims 1 to 3, wherein the amorphous polyester resin B has a glass transition temperature of 55°C or more and 75°C or less. The method for producing a toner for developing an electrostatic image according to any one of claims 1 to 4, wherein the crystalline polyester resin C has a melting point of 50°C or more and 100°C or less. The method for producing a toner for developing an electrostatic image according to any one of claims 1 to 5, wherein the naphthalene sulfonic acid formalin condensate is a β-naphthalene sulfonic acid formalin condensate sodium salt.