Method for manufacturing toner for electrostatic charge image development

Abstract

To provide a method for manufacturing a toner for electrostatic charge image development which is excellent in charging property and can suppress occurrence of fogging.SOLUTION: A method for manufacturing a toner for electrostatic charge image development includes a step of coagulating resin particles containing an amorphous resin and a crystalline resin in the same of different particles in an aqueous medium, and a step of fusing the resin particles. The amorphous resin contains an amorphous polyester-based resin A containing a polyester resin segment, and an addition polymerization resin segment containing a structural unit derived from a vinyl monomer having a hydrocarbon group having 9 or more and 24 or less carbon atoms, and the crystalline resin contains a crystalline polyester resin C containing a structural unit derived from monoalcohol having the hydrocarbon group having 9 or more and 24 or less carbon atoms and / or a structural unit derived from a monocarboxylic acid having the hydrocarbon group having 9 or more and 24 or less carbon atoms.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a toner for developing electrostatic images used in developing latent images formed in electrophotography, electrostatic recording, electrostatic printing and the like. [Background technology]

[0002] In the field of electrophotography, with the development of electrophotographic systems, there is a demand for the development of electrophotographic toners that can handle higher speeds and higher image quality. As the speed increases, the time it takes for the toner to be transferred to paper also becomes shorter, so toners with excellent charging properties are required. In addition, toners that can suppress the occurrence of fogging are required to handle higher image quality.

[0003] Patent Document 1 describes a method for producing a toner for developing electrostatic images, which includes the following steps 1 to 4 in this order, and in which amorphous polyester resin B contains 50 mol % or more of an ethylene oxide adduct of bisphenol A as an alcohol component, for the purpose of providing a method for producing a toner having a core-shell structure produced by a chemical method such as an aggregation fusion method, and in which the toner has excellent charging properties and good image quality. Step 1: A step of mixing and aggregating polyester resin particles X containing crystalline polyester resin C and amorphous polyester resin A with colorant particles in an aqueous medium to obtain aggregated particles 1, step 2: A step of aggregating resin particles Y containing amorphous polyester resin B with the aggregated particles 1 obtained in step 1 to obtain aggregated particles 2, step 3: A step of adding a naphthalenesulfonic acid-formalin condensate to aggregated particles 2 at a temperature equal to or lower than the melting point of crystalline polyester resin C, and step 4: A step of fusing aggregated particles 2 at a temperature equal to or higher than the glass transition temperature of amorphous polyester resin B and equal to or higher than the melting point of crystalline polyester resin C minus 10° C. to obtain toner particles. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2021-182046 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present inventors have found through their investigations that the toner obtained by the method for producing a toner for developing electrostatic images described in Patent Document 1 has room for improvement in terms of chargeability and suppression of fog generation. The present invention relates to a method for producing a toner for developing electrostatic images, which has excellent charging properties and is capable of suppressing the occurrence of fogging. [Means for solving the problem]

[0006] The present inventors have found that a toner for developing electrostatic images produced by a method including a step of aggregating and fusing, in an aqueous medium, resin particles which contain, in the same or different particles, an amorphous resin containing an amorphous polyester resin A including an addition polymerization resin segment which contains a structural unit derived from a vinyl monomer having a hydrocarbon group with a specific carbon number, and a crystalline resin containing a crystalline polyester resin C which contains a structural unit derived from a monoalcohol having a hydrocarbon group with a specific carbon number and / or a structural unit derived from a monocarboxylic acid having a hydrocarbon group with a specific carbon number, has excellent charging properties and is capable of suppressing the occurrence of fogging. The present invention relates to the following [1]. [1] A method for producing a toner for developing an electrostatic image, comprising a step of aggregating and fusing resin particles, the resin particles including an amorphous resin and a crystalline resin in the same or different particles, in an aqueous medium, the method comprising the steps of: the amorphous resin comprises an amorphous polyester-based resin A including a polyester resin segment and an addition polymerization resin segment including a structural unit derived from a vinyl monomer having a hydrocarbon group having 9 to 24 carbon atoms; The crystalline resin contains a crystalline polyester resin C containing a structural unit derived from a monoalcohol having a hydrocarbon group having 9 to 24 carbon atoms and / or a structural unit derived from a monocarboxylic acid having a hydrocarbon group having 9 to 24 carbon atoms. A method for producing a toner for developing electrostatic images. Effect of the Invention

[0007] According to the present invention, there is provided a method for producing a toner for developing electrostatic images, which has excellent charging properties and is capable of suppressing the occurrence of fogging. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] [Method of manufacturing toner for developing electrostatic images] The method for producing the toner for developing electrostatic images of the present invention includes a step of aggregating and a step of fusing resin particles containing the following amorphous resin and crystalline resin in the same or different particles in an aqueous medium. The amorphous resin contains an amorphous polyester resin A including a polyester resin segment and an addition polymerization resin segment including a structural unit derived from a vinyl monomer having a hydrocarbon group with a carbon number of 9 to 24. The crystalline resin contains a crystalline polyester resin C including a structural unit derived from a monoalcohol having a hydrocarbon group with a carbon number of 9 to 24 and / or a structural unit derived from a monocarboxylic acid having a hydrocarbon group with a carbon number of 9 to 24. According to the above-mentioned manufacturing method, a toner having excellent chargeability and capable of suppressing the occurrence of fog can be obtained. In the following, "toner for developing electrostatic images" may be simply referred to as "toner," "method for producing toner for developing electrostatic images" may be simply referred to as "production method," "amorphous polyester resin A containing a polyester resin segment, and an addition polymerization resin segment containing a structural unit derived from a vinyl monomer having a hydrocarbon group having from 9 to 24 carbon atoms" may be simply referred to as "resin A," and "crystalline polyester resin C containing a structural unit derived from a monoalcohol having a hydrocarbon group having from 9 to 24 carbon atoms and / or a structural unit derived from a monocarboxylic acid having a hydrocarbon group having from 9 to 24 carbon atoms" may be simply referred to as "resin C."

[0009] Although the detailed mechanism by which the production method of the present invention provides a toner having excellent chargeability and capable of suppressing the occurrence of fog is not clear, it is believed to be as follows. By including a crystalline polyester resin in a toner, the low-temperature fixing property of the toner can be improved. However, the crystalline polyester resin, which is relatively highly hydrophobic, is easily exposed on the toner surface and is difficult to disperse in a toner containing an amorphous resin. Therefore, the use of a crystalline polyester resin can cause a decrease in the chargeability of the toner and the occurrence of fogging. The manufacturing method of the present invention includes a step of aggregating and a step of fusing resin particles containing an amorphous resin and a crystalline resin in the same or different particles in an aqueous medium, and the amorphous polyester resin A contained in the amorphous resin and the crystalline polyester resin C contained in the crystalline resin each have a long-chain hydrocarbon group with a specific carbon number, and in the aqueous medium, these hydrocarbon groups face the inside of the resin particles and the toner particles as hydrophobic sites, and the hydrophobic interaction between the amorphous resin and the crystalline resin works strongly through the hydrocarbon groups. Therefore, the affinity between the amorphous polyester resin A and the crystalline polyester resin C is increased, and the highly hydrophobic crystalline resin can be uniformly dispersed in the toner particles, and the exposure of the crystalline polyester resin C to the toner surface is suppressed. As a result, it is considered that the chargeability of the toner is improved and a toner that can suppress the occurrence of fogging can be obtained. The above-mentioned mechanism regarding the effect of the present invention is merely a presumption, and the present invention is not limited thereto.

[0010] The definitions of various terms used in this specification are given below. In the specification, the carboxylic acid component of the polyester resin includes not only the compound itself, but also anhydrides that decompose during the reaction to produce a carboxylic acid, and alkyl esters of each carboxylic acid (alkyl groups having 1 to 3 carbon atoms). Whether a resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is defined as 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 with a crystallinity index of 0.6 or more and 1.4 or less. An amorphous resin is one in which no endothermic peak is observed, or, if observed, has a crystallinity index of less than 0.6 or more than 1.4. The crystallinity index can be appropriately adjusted by the types and ratios of raw material monomers, as well as production conditions such as reaction temperature, reaction time, and cooling rate. With respect to hydrocarbon groups, the use of "iso" in parentheses refers to both the presence and absence of the prefix, and indicates normal when the prefix is ​​absent. "(Meth)acrylic acid" means at least one selected from acrylic acid and methacrylic acid. By "styrenic compound" is meant unsubstituted or substituted styrene.

[0011] A method for producing a toner according to an embodiment of the present invention includes a step of aggregating and fusing, in an aqueous medium, resin particles that contain an amorphous resin containing resin A and a crystalline resin containing resin C in the same or different particles. The resin particles can be obtained, for example, by a phase inversion emulsification method using an amorphous resin and / or a crystalline resin, as described below. The present invention will be described below by taking this embodiment as an example.

[0012] <Step of aggregating resin particles> In the step of aggregating the resin particles, resin particles containing an amorphous resin containing resin A and a crystalline resin containing resin C in the same or different particles are aggregated in an aqueous medium to obtain aggregated particles 1. Here, in addition to the resin particles, it is preferable to further aggregate at least one of a colorant and a release agent, and it is more preferable to mix a resin particle dispersion containing resin particles with a colorant particle dispersion containing a colorant and / or a release agent particle dispersion containing a release agent to aggregate these particles.

[0013] In the present invention, the aqueous medium is a medium containing water as a main component, and the water content 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 the water, deionized water, ion-exchanged water, or distilled water is preferable. Examples of components other than water that can constitute an aqueous medium together with water include organic solvents that dissolve in water, such as alkyl alcohols having 1 to 5 carbon atoms; dialkyl ketones having 3 to 5 carbon atoms, such as acetone and methyl ethyl ketone; and cyclic ethers, such as tetrahydrofuran.

[0014] <Amorphous resin> The amorphous resin contains an amorphous polyester resin A including a polyester resin segment and an addition polymerization resin segment containing a structural unit derived from a vinyl monomer having a hydrocarbon group having 9 or more and 24 or less carbon atoms.

[0015] [Amorphous polyester resin A] The amorphous polyester resin A is preferably a composite resin in which a polyester resin segment and an addition polymerization resin segment containing a structural unit derived from a vinyl monomer having a hydrocarbon group having 9 to 24 carbon atoms are bonded together, and more preferably a resin in which the segments are chemically bonded together via a bireactive monomer that can react with both the raw material monomer of the polyester resin segment and the raw material monomer of the addition polymerization resin segment.

[0016] The polyester resin segment is obtained by polycondensation of an alcohol component and a carboxylic acid component.

[0017] Examples of the alcohol component include alkylene oxide adducts of aromatic diols, aliphatic diols, alicyclic diols, and trihydric or higher polyhydric alcohols. Among these, alkylene oxide adducts of aromatic diols are preferred from the viewpoint of obtaining a toner that is excellent in chargeability and can suppress the occurrence of fogging. The alkylene oxide adduct of an aromatic diol is preferably an alkylene oxide adduct of bisphenol A, more preferably an alkylene oxide adduct of formula (I):

[0018] [ka] (In the formula, OR 1 and R 2 O is an oxyalkylene group, and R 1 and R 2 each independently represents an ethylene group or a propylene group, x and y represent the average number of moles of alkylene oxide added and are each a positive number, and the sum of x and y is 1 or more, preferably 1.5 or more, and 16 or less, preferably 8 or less, and more preferably 4 or less.

[0019] Examples of the alkylene oxide adduct of bisphenol A represented by formula (I) include a propylene oxide adduct of bisphenol A and an ethylene oxide adduct of bisphenol A. Among these, it is preferable to contain a propylene oxide adduct of bisphenol A. The content of the alkylene oxide adduct of bisphenol A in the alcohol component is preferably 80 mol % or more, more preferably 90 mol % or more, and 100 mol % or less, and further preferably 100 mol %.

[0020] Examples of aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 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, and 3-methyl-1,5-pentanediol. Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane] and adducts of hydrogenated bisphenol A with alkylene oxides having 2 to 4 carbon atoms (average number of moles added: 2 to 12). Examples of trihydric or higher polyhydric alcohols include glycerin, pentaerythritol, trimethylolpropane, and sorbitol. These alcohol components may be used alone or in combination of two or more.

[0021] Examples of the carboxylic acid component include dicarboxylic acids and polycarboxylic acids having three or more carboxylic acids. Examples of dicarboxylic acids include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Among these, at least one selected from aromatic dicarboxylic acids and 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 45 mol% or more, more preferably 50 mol% or more, even more preferably 55 mol% or more, and is preferably 90 mol% or less, more preferably 80 mol% or less, even more preferably 65 mol% or less.

[0022] The aliphatic dicarboxylic acid preferably has 2 or more, more preferably 3 or more, and preferably has 30 or less, more preferably 20 or less. Examples of 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, azelaic acid, and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms. Examples of 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 and sebacic acid are preferred. The amount of the aliphatic dicarboxylic acid in the carboxylic acid component is preferably 10 mol % or more, more preferably 20 mol % or more, even more preferably 25 mol % or more, and is preferably 45 mol % or less, more preferably 40 mol % or less, even more preferably 35 mol % or less. An example of the alicyclic dicarboxylic acid is cyclohexanedicarboxylic acid.

[0023] The trivalent or higher polyvalent carboxylic acid is preferably a trivalent carboxylic acid, and examples thereof include trimellitic acid and its anhydride. When a trivalent or higher polycarboxylic acid is contained, the amount of the trivalent or higher polycarboxylic acid in the carboxylic acid component is preferably 3 mol % or more, more preferably 6 mol % or more, even more preferably 9 mol % or more, and is preferably 25 mol % or less, more preferably 20 mol % or less, even more preferably 15 mol % or less. These carboxylic acid components may be used alone or in combination of two or more.

[0024] The equivalent ratio of the carboxyl groups of the carboxylic acid component to the hydroxyl groups of the alcohol component [COOH groups / OH groups] is preferably 0.7 or more, more preferably 0.8 or more, and is preferably 1.3 or less, more preferably 1.2 or less.

[0025] From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the addition polymerization resin segment is an addition polymerization resin segment containing a constituent unit derived from a vinyl monomer having a hydrocarbon group having a carbon number of 9 to 24. The addition polymerization resin segment preferably further contains a constituent unit derived from a styrene-based compound.

[0026] From the viewpoint of obtaining a toner having excellent electrostatic properties and capable of suppressing the occurrence of fog, the number of carbon atoms in the hydrocarbon group of the vinyl monomer having a hydrocarbon group is preferably 10 or more, more preferably 13 or more, even more preferably 15 or more, and is preferably 23 or less, more preferably 21 or less.

[0027] Examples of the hydrocarbon group include aliphatic hydrocarbon groups such as alkyl groups, alkenyl groups, and alkynyl groups, of which alkyl and alkenyl groups are preferred, and alkyl groups are more preferred. The hydrocarbon group may be branched or linear. Examples of the raw material vinyl monomer for the addition polymerization resin segment having a hydrocarbon group include (meth)acrylic acid esters having a hydrocarbon group and olefins having a hydrocarbon group. Among these, from the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fogging, (meth)acrylic acid esters having a hydrocarbon group are preferred. In the case of (meth)acrylic acid esters, the hydrocarbon group is the alcohol side residue of the ester.

[0028] Examples of (meth)acrylic acid esters having a hydrocarbon group include (iso)decyl (meth)acrylate, (iso)dodecyl (meth)acrylate (hereinafter also referred to as (iso)lauryl (meth)acrylate), (iso)palmityl (meth)acrylate, (iso)stearyl (meth)acrylate, (iso)behenyl (meth)acrylate, and the like, of which (iso)lauryl (meth)acrylate, (iso)stearyl (meth)acrylate, and (iso)behenyl (meth)acrylate are preferred, and (iso)stearyl (meth)acrylate and (iso)behenyl (meth)acrylate are more preferred.

[0029] From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the content of structural units derived from vinyl monomers having a hydrocarbon group having 9 to 24 carbon atoms in Resin A is preferably 1 mass % or more, more preferably 2 mass % or more, even more preferably 3 mass % or more, and is preferably 10 mass % or less, more preferably 8 mass % or less, even more preferably 6 mass % or less. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the content of the constituent units derived from a vinyl monomer having a hydrocarbon group having 9 to 24 carbon atoms in the addition polymerization 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 is preferably 35% by mass or less, more preferably 30% by mass or less, even more preferably 25% by mass or less.

[0030] The styrene-based compound may be substituted or unsubstituted styrene. Examples of the substituent 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. Specific examples include styrenes such as styrene, methylstyrene, α-methylstyrene, β-methylstyrene, tert-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid, or a salt thereof, and preferably includes styrene, more preferably styrene. In the addition polymerization resin segment, the content of the structural unit derived from a styrene-based compound is preferably 50% by mass or more, more preferably 55% by mass or more, even more preferably 60% by mass or more, from the viewpoint of obtaining a toner that has excellent charging properties and can suppress the occurrence of fog, and is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 85% by mass or less. Other than the above, examples of raw vinyl monomers that can be used for the addition polymerization resin segment include ethylenically unsaturated monoolefins such as ethylene and propylene; conjugated dienes such as butadiene; halovinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; (meth)acrylic acid esters having a hydrocarbon group having 1 to 8 carbon atoms, such as methyl (meth)acrylate; (meth)acrylic acid aminoalkyl esters such as dimethylaminoethyl (meth)acrylate; vinyl ethers such as methyl vinyl ether; vinylidene halides such as vinylidene chloride; and N-vinyl compounds such as N-vinylpyrrolidone.

[0031] As the raw material vinyl monomer for the addition polymerization resin segment, from the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, a combination of a vinyl monomer having a hydrocarbon group having from 9 to 24 carbon atoms and a styrene-based compound is preferable, a combination of an alkyl ester of (meth)acrylic acid having an alkyl group having from 10 to 24 carbon atoms and styrene is more preferable, and among these, a combination of lauryl (meth)acrylate, stearyl (meth)acrylate, or behenyl (meth)acrylate and styrene is even more preferable, and a combination of stearyl (meth)acrylate or behenyl (meth)acrylate and styrene is even more preferable. When a vinyl monomer having a hydrocarbon group with 9 or more and 24 or less carbon atoms is used in combination with a styrene-based compound, the mass ratio of the constituent units derived from the vinyl monomer having a hydrocarbon group with 9 or more and 24 or less carbon atoms in the addition polymerization resin segment to the constituent units derived from the styrene-based compound [constituent units derived from the vinyl monomer having a hydrocarbon group with 9 or more and 24 or less carbon atoms / constituent units derived from the styrene-based compound] is, from the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fogging, preferably 5 / 95 or more, more preferably 10 / 90 or more, even more preferably 15 / 85 or more, and is preferably 50 / 50 or less, more preferably 45 / 55 or less, even more preferably 40 / 60 or less.

[0032] The total content of the constituent units derived from vinyl monomers having a hydrocarbon group having 9 to 24 carbon atoms and the constituent units derived from styrene-based compounds in the addition polymerization resin segment is preferably 90% by mass or more, more preferably 95% by mass or more, even more preferably 99% by mass or more, and even more preferably 100% by mass, from the viewpoint of obtaining a toner that has excellent charging properties and can suppress the occurrence of fog.

[0033] Resin A preferably has a constitutional unit derived from a bireactive monomer bonded to a polyester resin segment and an addition polymerization resin segment via a covalent bond. Examples of the bireactive monomer include addition polymerizable monomers having at least one functional group selected from a hydroxyl group, a carboxyl 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 carboxyl group are preferred, and addition polymerizable monomers having a carboxyl group are more preferred. Examples of the addition polymerizable monomer having a carboxy group include acrylic acid, methacrylic acid, fumaric acid, and maleic acid. Among these, from the viewpoint of reactivity in both the polycondensation reaction and the addition polymerization reaction, acrylic acid and methacrylic acid are preferred, and acrylic acid is more preferred. The amount of the structural units derived from the bireactive monomer is preferably 1 part by mol or more, more preferably 5 parts by mol or more, and even more preferably 8 parts by mol or more, relative to 100 parts by mol of the structural units derived from the alcohol component of the polyester resin segment of Resin A, and is preferably 30 parts by mol or less, more preferably 25 parts by mol or less, and even more preferably 20 parts by mol or less.

[0034] The content of the polyester resin segment in the resin A is preferably 60% by mass or more, more preferably 65% ​​by mass or more, and even more preferably 70% by mass or more, and is preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less, based on the total amount of the polyester resin segment and the addition polymerization resin segment. The constitutional unit derived from the bireactive monomer is defined as a polyester resin segment.

[0035] The content of the addition polymerization resin segment in Resin A is preferably 5 mass% or more, more preferably 10 mass% or more, even more preferably 15 mass% or more, and preferably 40 mass% or less, more preferably 35 mass% or less, even more preferably 30 mass% or less, based on the total amount of the polyester resin segment and the addition polymerization resin segment.

[0036] The amount of the constitutional units derived from the bireactive monomer in the resin A is preferably 0.1 mass% or more, more preferably 0.5 mass% or more, even more preferably 0.8 mass% or more, and is preferably 10 mass% or less, more preferably 7 mass% or less, even more preferably 4 mass% or less, based on the total amount of the polyester resin segment and the addition polymerization resin segment.

[0037] The total amount of polyester resin segments and addition polymerization resin segments in resin A is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and is 100% by mass or less, preferably 100% by mass.

[0038] The above amount is calculated based on the ratio of the amounts of the polyester resin segment, the raw material monomer for the addition polymerization resin segment, the bireactive monomer, and the radical polymerization initiator, and the mass of the polyester resin segment, etc. is based on the mass excluding the mass of water generated by polycondensation. 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.

[0039] (Production of amorphous polyester resin A) Resin A may be produced, for example, by a method including a step A of polycondensing an alcohol component and a carboxylic acid component, and a step B of addition polymerizing raw material monomers of the addition polymerization resin segment and a bireactive monomer. Step B may be carried out after step A, step B may be carried out after step A, or step A and step B may be carried out simultaneously. In step A, a part of the carboxylic acid component may be subjected to a polycondensation reaction, and then step B may be carried out, after which the remainder of the carboxylic acid component may be added to the polymerization system to further advance the polycondensation reaction.

[0040] In step A, polycondensation may be carried out using an esterification catalyst and an esterification promoter, if necessary. When a monomer having an unsaturated bond such as fumaric acid is used in the polycondensation, a polymerization inhibitor may be used as necessary. Examples of the esterification catalyst include tin compounds such as dibutyltin oxide and tin(II) di(2-ethylhexanoate), and titanium compounds such as titanium diisopropoxybis(triethanolaminate). Examples of the esterification promoter that can be used together with the esterification catalyst include gallic acid (3,4,5-trihydroxybenzoic acid). When an esterification catalyst is used, the amount of the esterification catalyst used is preferably 0.01 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component which are the raw material monomers of the resin A. When an esterification promoter is used, the amount of the esterification promoter used is preferably 0.001 part by mass or more and 1 part by mass or less per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Furthermore, examples of the polymerization inhibitor include radical polymerization inhibitors such as 4-tert-butylcatechol. When a polymerization inhibitor is used, the amount of the polymerization inhibitor used is preferably 0.001 part by mass or more and 1 part by mass or less based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. The temperature of the polycondensation reaction is preferably 120° C. or higher, more preferably 160° C. or higher, and even more preferably 180° C. or higher, and is preferably 250° C. or lower, more preferably 240° C. or lower. The polycondensation may be carried out in an inert gas atmosphere.

[0041] Examples of the radical polymerization initiator for the addition polymerization in step B 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 radical polymerization initiator used is preferably 1 part by mass or more and 20 parts by mass or less based on 100 parts by mass of the raw material monomer of the addition polymerization resin segment. The temperature of the 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, and further preferably 210° C. or lower.

[0042] (Physical properties of amorphous polyester resin A) From the viewpoint of obtaining a toner having excellent electrostatic properties and capable of suppressing the occurrence of fog, the softening point of resin A is preferably 70°C or higher, more preferably 80°C or higher, and even more preferably 90°C or higher, and is preferably 130°C or lower, and more preferably 120°C or lower. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the glass transition temperature of resin A is preferably 30° C. or higher, more preferably 40° C. or higher, even more preferably 45° C. or higher, and is preferably 80° C. or lower, more preferably 70° C. or lower, even more preferably 60° C. or lower.

[0043] The acid value of 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 is preferably 40 mgKOH / g or less, more preferably 30 mgKOH / g or less, even more preferably 25 mgKOH / g or less. The softening point, glass transition temperature, and acid value of Resin A can be appropriately adjusted by the types and amounts of raw material monomers used, as well as production conditions such as reaction temperature, reaction time, and cooling rate, and these values ​​can be determined by the methods described in the examples. When two or more resins A are used in combination, the softening point, glass transition temperature and acid value of the resulting mixture are preferably within the above-mentioned ranges.

[0044] The amorphous resin preferably contains 80% by mass or more of resin A. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the content of resin A in the amorphous resin is more preferably 82% by mass or more, even more preferably 84% by mass or more, and even more preferably 86% by mass or more, and may be 100% by mass or less, or 95% by mass or less.

[0045] [Amorphous polyester resin B] The amorphous resin may contain an amorphous resin other than resin A, as long as the effect of the present invention is not impaired. Examples of such amorphous resins include amorphous polyester resins that do not contain addition polymerization resin segments containing a structural unit derived from a vinyl monomer having a hydrocarbon group with a carbon number of 9 to 24, polyester resins, and modified polyester resins. Examples of modified polyester resins include urethane modified polyester resins and epoxy modified polyester resins. Among these, polyester resins are preferred.

[0046] <Crystalline resin> The crystalline resin is used as a binder resin for toner, and contains crystalline polyester resin C. Crystalline polyester resin C is a polycondensate of an alcohol component and a carboxylic acid component, and from the viewpoint of obtaining a toner that is excellent in chargeability and can suppress the occurrence of fog, contains a constitutional unit derived from a monoalcohol having a hydrocarbon group with 9 to 24 carbon atoms and / or a constitutional unit derived from a monocarboxylic acid having a hydrocarbon group with 9 to 24 carbon atoms at the end of the polyester molecular chain. That is, the raw material monomer of crystalline polyester resin C contains a monoalcohol having a hydrocarbon group with 9 to 24 carbon atoms and / or a monocarboxylic acid having a hydrocarbon group with 9 to 24 carbon atoms.

[0047] [Crystalline polyester resin C] The alcohol component preferably comprises an α,ω-aliphatic diol. The α,ω-aliphatic diol preferably has 2 or more carbon atoms, and preferably has 16 or less, more preferably 10 or less, and further preferably 6 or less. Examples of α,ω-aliphatic diols 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, and 1,14-tetradecanediol. Among these, ethylene glycol and 1,4-butanediol are preferred, and ethylene glycol is more preferred.

[0048] When the alcohol component does not contain a monoalcohol having a hydrocarbon group having 9 to 24 carbon atoms, 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 is 100 mol % or less, preferably 100 mol %.

[0049] When the alcohol component contains a monoalcohol having a hydrocarbon group having 9 to 24 carbon atoms, the amount of α,ω-aliphatic diol in the alcohol component is preferably 75 mol% or more, more preferably 80 mol% or more, even more preferably 84 mol% or more, even more preferably 86 mol% or more, and preferably 99.5 mol% or less, more preferably 98 mol% or less, even more preferably 96 mol% or less.

[0050] The alcohol component may contain other alcohol components different from the α,ω-aliphatic diol and the monoalcohol having a hydrocarbon group having from 9 to 24 carbon atoms. Examples of the other alcohol components include aliphatic diols other than α,ω-aliphatic diols such as 1,2-propylene glycol and neopentyl glycol; aromatic diols such as alkylene oxide adducts of bisphenol A; and trihydric or higher alcohols such as glycerin, pentaerythritol and trimethylolpropane. These alcohol components may be used alone or in combination.

[0051] The carboxylic acid component preferably comprises an α,ω-aliphatic dicarboxylic acid. The α,ω-aliphatic dicarboxylic acid has 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 α,ω-aliphatic dicarboxylic acids include fumaric acid, sebacic acid, 1,12-dodecanedioic acid, and tetradecanedioic acid. Among these, 1,12-dodecanedioic acid is preferred. These carboxylic acid components may be used alone or in combination.

[0052] When the carboxylic acid component does not contain a monocarboxylic acid having a hydrocarbon group having 9 to 24 carbon atoms, the amount of α,ω-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 is 100 mol % or less, preferably 100 mol %.

[0053] When the carboxylic acid component contains a monocarboxylic acid having a hydrocarbon group having 9 to 24 carbon atoms, the amount of α,ω-aliphatic dicarboxylic acid in the carboxylic acid component is preferably 75 mol % or more, more preferably 80 mol % or more, even more preferably 84 mol % or more, even more preferably 86 mol % or more, and preferably 99.5 mol % or less, more preferably 98 mol % or less, even more preferably 96 mol % or less.

[0054] The carboxylic acid component may contain other carboxylic acid components different from α,ω-aliphatic dicarboxylic acids and monocarboxylic acids having a hydrocarbon group with a carbon number of 9 to 24. Examples of other carboxylic acid components include aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid; and polyvalent carboxylic acids having three or more carboxylic acids. These carboxylic acid components may be used alone or in combination.

[0055] From the viewpoint of obtaining a toner having excellent electrostatic properties and capable of suppressing the occurrence of fog, the number of carbon atoms in the hydrocarbon group of the monoalcohol is 9 or more, preferably 10 or more, more preferably 13 or more, and even more preferably 15 or more, and is 24 or less, preferably 23 or less, and more preferably 21 or less. Examples of the hydrocarbon group include aliphatic hydrocarbon groups such as alkyl groups, alkenyl groups, and alkynyl groups, of which alkyl and alkenyl groups are preferred, and alkyl groups are more preferred. The hydrocarbon group may be branched or linear. Examples of monoalcohols having a hydrocarbon group having 9 to 24 carbon atoms include aliphatic alcohols such as decanol, lauryl alcohol, palmityl alcohol, stearyl alcohol, behenyl alcohol, and lignoceryl alcohol. Among these, stearyl alcohol and behenyl alcohol are preferred, and stearyl alcohol is more preferred. These monoalcohols may be used alone or in combination.

[0056] From the viewpoint of obtaining a toner having excellent electrostatic properties and capable of suppressing the occurrence of fog, the number of carbon atoms in the hydrocarbon group of the monocarboxylic acid is 9 or more, preferably 10 or more, more preferably 13 or more, and even more preferably 15 or more, and is 24 or less, preferably 23 or less, and more preferably 21 or less. Examples of the hydrocarbon group include aliphatic hydrocarbon groups such as alkyl groups, alkynyl groups, and alkenyl groups, of which alkyl and alkenyl groups are preferred, and alkyl groups are more preferred. The hydrocarbon group may be branched or linear. Examples of monocarboxylic acids having a hydrocarbon group having 9 to 24 carbon atoms include capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, etc. Among these, from the viewpoint of obtaining a toner having excellent chargeability and capable of suppressing the occurrence of fogging, preferred are lauric acid, stearic acid, and behenic acid, and more preferred are stearic acid and behenic acid. These monocarboxylic acids may be used alone or in combination.

[0057] When the alcohol component contains a monoalcohol having a hydrocarbon group having 9 to 24 carbon atoms, the content of the monoalcohol in the alcohol component is, from the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, preferably 0.5 mol % or more, more preferably 2 mol % or more, even more preferably 4 mol % or more, and is preferably 20 mol % or less, more preferably 16 mol % or less, even more preferably 14 mol % or less. When the carboxylic acid component contains a monocarboxylic acid having a hydrocarbon group having 9 to 24 carbon atoms, the content of the monocarboxylic acid in the carboxylic acid component is, from the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, preferably 0.5 mol % or more, more preferably 2 mol % or more, even more preferably 4 mol % or more, and is preferably 20 mol % or less, more preferably 16 mol % or less, even more preferably 14 mol % or less. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fogging, the total content of the monoalcohol having a hydrocarbon group with 9 to 24 carbon atoms and the monocarboxylic acid having a hydrocarbon group with 9 to 24 carbon atoms, based on the total amount of the alcohol component and the carboxylic acid component, is preferably 0.2 mol % or more, more preferably 0.5 mol % or more, even more preferably 1 mol % or more, even more preferably 3 mol % or more, and is preferably 20 mol % or less, more preferably 10 mol % or less, even more preferably 7 mol % or less.

[0058] The raw material monomer of the crystalline polyester resin C preferably contains a monoalcohol having a hydrocarbon group with 9 to 24 carbon atoms, or a monocarboxylic acid having a hydrocarbon group with 9 to 24 carbon atoms.

[0059] The equivalent ratio of the carboxyl groups of the carboxylic acid component to the hydroxyl groups of the alcohol component (COOH groups / OH groups) is preferably 0.7 or more, more preferably 0.8 or more, and is preferably 1.3 or less, more preferably 1.2 or less.

[0060] (Physical properties of crystalline polyester resin C) From the viewpoint of obtaining a toner having excellent electrostatic properties and capable of suppressing the occurrence of fog, the softening point of resin C is preferably 65°C or higher, more preferably 70°C or higher, even more preferably 75°C or higher, and is preferably 100°C or lower, more preferably 95°C or lower, even more preferably 90°C or lower. From the viewpoint of obtaining a toner having excellent electrostatic properties and capable of suppressing the occurrence of fog, the melting point of resin C is preferably 65°C or higher, more preferably 70°C or higher, even more preferably 75°C or higher, and is preferably 100°C or lower, more preferably 95°C or lower, even more preferably 90°C or lower.

[0061] The acid value of resin C is preferably 1 mgKOH / g or more, more preferably 3 mgKOH / g or more, and preferably 20 mgKOH / g or less, more preferably 15 mgKOH / g or less, and even more preferably 10 mgKOH / g or less.

[0062] The softening point, melting point, and acid value of the resin C can be appropriately adjusted by the types and ratios of the raw material monomers, as well as the production conditions such as the reaction temperature, reaction time, and cooling rate. These values ​​are determined by the method described in the Examples below. When two or more types of resin C are used in combination, it is preferable that the softening point, melting point, and acid value obtained as a mixture of them are each within the above-mentioned ranges.

[0063] Resin C can be obtained, for example, by polycondensation of an alcohol component and a carboxylic acid component. The polycondensation conditions can be the same as those described above for polycondensation of Resin A.

[0064] The crystalline resin preferably contains 90% by mass or more of crystalline polyester resin C. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the content of resin C in the crystalline resin is more preferably 95% by mass or more, even more preferably 97% by mass or more, and is preferably 100% by mass or less, more preferably 100% by mass.

[0065] From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the total content of the amorphous resin and the crystalline resin in the resin particles is preferably 80% by mass or more, more preferably 90% by mass or more, and is preferably 100% by mass or less, more preferably 100% by mass.

[0066] From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fogging, the mass ratio of resin C to resin A in the toner particles [resin C / resin A] is preferably 3 / 97 or more, more preferably 5 / 95 or more, even more preferably 7 / 93 or more, and is preferably 45 / 55 or less, more preferably 40 / 60 or less, even more preferably 35 / 65 or less.

[0067] From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the content of the amorphous resin in the toner particles is preferably 45% by mass or more, more preferably 50% by mass or more, even more preferably 55% by mass or more, and is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 85% by mass or less. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the content of the crystalline resin in the toner particles is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, and is preferably 30% by mass or less, more preferably 25% by mass or less. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the total content of the amorphous resin and the crystalline resin in the toner particles is preferably 60% by mass or more, more preferably 65% ​​by mass or more, even more preferably 70% by mass or more, and is preferably 99% by mass or less, more preferably 95% by mass or less.

[0068] [Method for producing resin particles] The resin particles of the amorphous resin and the resin particles of the crystalline resin may be produced as an aqueous dispersion of resin particles containing the amorphous resin and the crystalline resin in the same or different particles. An aqueous medium can be used for the aqueous dispersion.

[0069] Dispersion can be performed using a known method, but it is preferable to disperse by a phase inversion emulsification method. For example, the phase inversion emulsification method includes 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. A method in which an aqueous medium is added to an organic solvent solution of a resin to perform phase inversion emulsification is preferable. The organic solvent used for phase inversion emulsification is not particularly limited as long as it dissolves the resin and is water-soluble, and examples thereof include methyl ethyl ketone. A neutralizing agent may be added 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; and nitrogen-containing basic substances such as ammonia, trimethylamine, and diethanolamine. Among these, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide are preferred. The degree of neutralization of the resin contained in the resin particles is preferably 40 mol % or more, more preferably 45 mol % or more, even more preferably 50 mol % or more, and preferably 100 mol % or less, more preferably 80 mol % or less, even more preferably 70 mol % or less. The degree of neutralization of the resin contained in the resin particles can be calculated by the following formula. Degree of neutralization (mol%)=[{weight of neutralizing agent added (g) / equivalent weight of neutralizing agent} / [{weighted average acid value of resin constituting resin particle (mgKOH / g)×weight of resin constituting resin particle (g)} / (56×1000)]]×100

[0070] While stirring the organic solvent solution or the molten resin, the aqueous medium is gradually added to cause phase inversion. From the viewpoint of improving the dispersion stability of the resin particles, the temperature of the organic solvent solution when the aqueous medium is added is preferably not less than the glass transition temperature of resin A, more preferably not less than 60°C, even more preferably not less than 70°C, and is preferably not more than 100°C, more preferably not more than 90°C, even more preferably not more than 80°C.

[0071] After the phase inversion emulsification, the organic solvent may be removed from the obtained dispersion by distillation or the like, if necessary. Also, the resin particles may be isolated by filtration or the like. In this case, the remaining amount of the organic solvent in the dispersion is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably substantially 0% by mass.

[0072] Volume median diameter D of resin particles in dispersion 50 From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the particle size is preferably 0.05 μm or more, more preferably 0.08 μm or more, and is preferably 1 μm or less, more preferably 0.6 μm or less, and even more preferably 0.3 μm or less. From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, the CV value of the resin particles in the dispersion is preferably 10% or more, more preferably 15% or more, and is preferably 40% or less, more preferably 35% or less. Volume median diameter D of resin particles in dispersion 50 The CV value is measured by the method described in the Examples.

[0073] From the viewpoint of improving the productivity of the toner and the dispersion stability of the aqueous dispersion of the resin particles, the solids concentration of the aqueous dispersion of the resin particles is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and is preferably 40% by mass or less, more preferably 35% by mass or less. The solid content is the total amount of non-volatile components.

[0074] [Coloring Agent] The colorant is preferably mixed as colorant particles with resin particles and aggregated to be contained in aggregate particles 1. As the colorant, any of the dyes, pigments, etc. used as toner colorants can be used. Examples of colorants include carbon black, phthalocyanine blue, permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, disazo yellow, and pigment red 269. The toner may be either a black toner or a color toner other than black.

[0075] (Colorant particle dispersion) The colorant particles are preferably obtained as a dispersion of the colorant particles by dispersing the colorant and an aqueous medium using a dispersing machine such as a homogenizer, an ultrasonic dispersing machine, etc. From the viewpoint of improving the dispersion stability of the colorant, the dispersion is preferably carried out in the presence of a surfactant or an addition polymer (hereinafter, the addition polymer used to disperse the colorant is also referred to as "addition polymer E"). Examples of the surfactant include a nonionic surfactant, an anionic surfactant, and a cationic surfactant. The addition polymer E preferably has a constituent unit derived from an addition polymerizable monomer a having an aromatic group, and further preferably contains at least one selected from the group consisting of an addition polymerizable monomer b having an ionic group, an addition polymerizable monomer c having a polyalkylene oxide group, and a macromonomer d. For the colorant particle dispersion using the addition polymer E, see JP2021-026129A.

[0076] From the viewpoint of image density of the printed matter, the content of the colorant in the colorant particle dispersion is preferably 2% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, and is preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less. The solids 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 is preferably 40% by mass or less, more preferably 30% by mass or less.

[0077] Volume median particle size D of colorant particles 50 From the viewpoint of improving the dispersibility of the colorant in the toner particles, the average particle diameter is preferably 0.05 μm or more, more preferably 0.08 μm or more, and is preferably 0.4 μm or less, more preferably 0.3 μm or less, and further preferably 0.25 μm or less. From the viewpoint of improving the dispersibility of the colorant in the toner particles, the CV value of the colorant particles is preferably 10% or more, more preferably 15% or more, and is preferably 40% or less, more preferably 35% or less, and even more preferably 30% or less. Volume median particle size D of colorant particles 50 and CV values ​​are measured by the methods in the Examples.

[0078] From the viewpoint of image density of the printed matter, the content of the colorant in the toner particles is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 3% by mass, and is preferably 15% by mass or less, more preferably 10% by mass or less, even more preferably 8% by mass or less.

[0079] [Release Agent] The release agent is preferably contained in the aggregated particles 1 by mixing it as release agent particles with the resin particles and aggregating them. Examples of the release agent include polypropylene wax, polyethylene wax, polypropylene-polyethylene copolymer wax, hydrocarbon waxes such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and oxides thereof, ester waxes such as carnauba wax, montan wax, and deacidified waxes thereof, and 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.

[0080] The melting point of the release agent is preferably 60° C. or higher, more preferably 70° C. or higher, and is preferably 160° C. or lower, more preferably 140° C. or lower, and further preferably 120° C. or lower. The content of the release agent in the toner particles is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 5% by mass or more, and is preferably 15% by mass or less, more preferably 10% by mass or less.

[0081] (Release agent particle dispersion) The release agent particle dispersion can be obtained by using a surfactant, but is preferably obtained by mixing the release agent and resin particles. By preparing the release agent particles using the release agent and resin particles, the release agent particles are stabilized by the resin constituting the resin particles, and it becomes possible to disperse the release agent in an aqueous medium without using a surfactant. It is considered that the release agent particle dispersion has a structure in which a large number of resin particles are attached to the surface of the release agent particles. The resin constituting the resin particles 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 polymerization resin segment. For the release agent particle dispersion and the composite resin D, reference is made to JP 2021-182045 A. In addition, the aforementioned amorphous polyester resin A may be used.

[0082] Volume median particle size D of release agent particles 50 From the viewpoint of obtaining uniform aggregated particles 1 by aggregation, the average particle size is preferably 0.05 μm or more, more preferably 0.1 μm or more, even more preferably 0.2 μm or more, and 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 15% or more, and is preferably 40% or less, more preferably 35% or less, and further preferably 30% or less. Volume median particle size D of release agent particles 50 The CV value is measured by the method described in the Examples.

[0083] Aggregated particles 1 may also contain additives such as charge control agents, magnetic powders, flowability improvers, conductivity adjusters, reinforcing fillers such as fibrous substances, antioxidants, antiaging agents, and cleaning improvers.

[0084] [Surfactant] In the step of aggregating the resin particles, when the dispersions of the respective particles are mixed to prepare a mixed dispersion, the process may be carried out in the presence of a surfactant from the viewpoint of improving the dispersion stability of the resin particles, the release agent particles, the colorant particles, etc. Examples of the surfactant include anionic surfactants such as alkylbenzene sulfonates and alkyl ether sulfates; and nonionic surfactants such as polyoxyethylene alkyl ethers and polyoxyethylene alkenyl ethers. When a surfactant is used, the total amount used is preferably 0.1 part by mass or more, more preferably 0.3 part by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less, per 100 parts by mass of the combined total of the amorphous resin and the crystalline resin.

[0085] [Flocculant] In the step of aggregating the resin particles, it is preferable to add an aggregating agent from the viewpoint of efficient aggregation. Examples of the flocculant include cationic surfactants such as quaternary salts, organic flocculants such as polyethyleneimine, and inorganic flocculants. Examples of the inorganic flocculant include inorganic metal salts such as sodium sulfate, sodium nitrate, sodium chloride, calcium chloride, and calcium nitrate; inorganic ammonium salts such as ammonium sulfate, ammonium chloride, and ammonium nitrate; and divalent or higher metal complexes. From the viewpoint of improving the coagulation properties and obtaining uniformly coagulated particles 1, inorganic coagulants having a valence of 1 to 5 are preferred, inorganic metal salts having a valence of 1 to 2 and inorganic ammonium salts are more preferred, inorganic ammonium salts are even more preferred, and ammonium sulfate is even more preferred.

[0086] For example, 5 parts by mass or more and 50 parts by mass or less of the aggregating agent is added to a mixed dispersion liquid containing resin particles, release agent particles, and colorant particles at 0° C. or more and 40° C. or less, relative to a total of 100 parts by mass of the amorphous resin and crystalline resin, and the resin particles, release agent particles, and colorant particles are aggregated in an aqueous medium to obtain aggregated particles 1. Furthermore, from the viewpoint of promoting aggregation, it is preferable to increase the temperature of the dispersion liquid after adding the aggregating agent.

[0087] Examples of a method for stopping the aggregation include a method of cooling the dispersion, a method of adding an aggregation terminator, a method of diluting the dispersion, etc. From the viewpoint of reliably preventing unnecessary aggregation, a method of stopping the aggregation by adding an aggregation terminator is preferred.

[0088] [Aggregation Stopper] The aggregation terminator is preferably a surfactant, more preferably an anionic surfactant. Examples of the anionic surfactant include alkylbenzenesulfonate, alkyl sulfate, alkyl ether sulfate, polyoxyalkylene alkyl ether sulfate, arylsulfonate, and arylsulfonic acid formalin condensate, and are preferably an alkali metal salt of arylsulfonic acid formalin condensate, and more preferably a sodium salt of naphthalenesulfonic acid formalin condensate. These may be used alone or in combination. The aggregation terminator may be added in the form of an aqueous solution. The amount of the aggregation terminator added is preferably 1 part by mass or more, and more preferably 3 parts by mass or more, relative to 100 parts by mass of the total of the amorphous resin and the crystalline resin, from the viewpoint of reliably preventing unnecessary aggregation, and is preferably 15 parts by mass or less, more preferably 12 parts by mass or less, and even more preferably 10 parts by mass or less, from the viewpoint of reducing residue in the toner.

[0089] Volume median particle size D of aggregate 1 50 is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 7 μm or less.

[0090] In the present invention, after the step of aggregating the resin particles and before the step of fusing, a step of aggregating the shell resin particles may be included in which shell resin particles containing an amorphous resin (preferably an amorphous polyester resin) are attached to the obtained aggregated particles 1 to obtain aggregated particles 2. By including the step of aggregating the shell resin particles, toner particles having a core-shell structure can be obtained. Here, examples of the amorphous resin used for the shell resin particles include the above-mentioned polyester resin A and polyester resin B. The shell resin particles are obtained by the same method as that for the above-mentioned resin particles. Furthermore, when the toner manufacturing method includes a step of aggregating shell resin particles, it is preferable to stop the aggregation in the step when the aggregated particles 2 have grown to an appropriate particle size for toner particles, and a method of stopping the aggregation by adding the above-mentioned aggregation terminator is preferable.

[0091] <Fusing process> In the fusion step, for example, the aggregated particles are fused in an aqueous medium. By fusion, the particles contained in the aggregated particles are fused together to obtain fused particles. In the fusion step, from the viewpoint of improving the fusion properties of the aggregated particles, the aggregated particles are maintained at a temperature equal to or higher than the glass transition temperature of the resin having the highest glass transition temperature among the resins contained in the aggregated particles. From the viewpoint of improving the productivity of the toner, the holding (heating) temperature when fusing the aggregated particles is preferably equal to or higher than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous resins, more preferably equal to or higher than a temperature 2° C. higher than the glass transition temperature of the resin, even more preferably equal to or higher than a temperature 5° C. higher than the glass transition temperature of the resin, and is preferably equal to or lower than a temperature 30° C. higher than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous resins, more preferably equal to or lower than a temperature 25° C. higher than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous resins, even more preferably equal to or lower than a temperature 20° C. higher than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous resins. In this case, it is preferable to maintain the temperature at the above temperature until the desired circularity is achieved.

[0092] The volume median particle size D of the fused particles obtained by fusion 50is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 7 μm or less.

[0093] The circularity of the fused particles obtained by fusion is preferably 0.955 or more, more preferably 0.960 or more, and is preferably 0.990 or less, more preferably 0.985 or less, and further preferably 0.980 or less. The fusion is preferably terminated after the above-mentioned preferred circularity is reached. The circularity is measured by the method described in the Examples.

[0094] <Post-processing process> After the fusion step, a post-treatment step may be performed, and the fused particles are isolated to obtain toner particles. Since the fused particles obtained in the fusion step are present in an aqueous medium, it is preferable to first perform solid-liquid separation. For the solid-liquid separation, a suction filtration method or the like is preferably used. It is preferable to wash the solid-liquid separation product. In this case, it is preferable to remove the surfactant added, and therefore it is preferable to wash the product with an aqueous medium at a temperature below the cloud point of the surfactant. It is preferable to wash the product several times. Next, drying is preferably performed. Examples of the drying method include vacuum low-temperature drying, vibration-type fluidized bed drying, spray drying, freeze drying, and flash jet drying.

[0095] [Toner Particles] Volume median particle size of toner particles D 50 From the viewpoint of obtaining a toner having excellent charging properties and capable of suppressing the occurrence of fog, and from the viewpoint of further improving the cleaning properties of the toner, the particle size is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 7 μm or less.

[0096] The circularity of the toner particles is preferably 0.955 or more, more preferably 0.960 or more, from the viewpoint of obtaining high quality images, and is preferably 0.990 or less, more preferably 0.985 or less, and even more preferably 0.980 or less, from the viewpoint of cleaning properties.

[0097] The CV value of the toner particles is preferably 10% or more, more preferably 15% or more, and even more preferably 20% or more from the viewpoint of improving the productivity of the toner, and is preferably 40% or less, more preferably 35% or less, and even more preferably 30% or less from the viewpoint of obtaining high-quality images. Volume median particle size of toner particles D 50 The CV value can be measured by the method described in the Examples.

[0098] <Toner for developing electrostatic images> The toner for developing electrostatic images obtained by the method for producing a toner for developing electrostatic images of the present invention contains toner particles. The toner particles can be used as they are, but it is preferable to use the toner after adding a fluidizing agent or the like as an external additive to the surface of the toner particles.

[0099] [External additives] Examples of the external additive include inorganic fine particles such as hydrophobic silica, titanium oxide, alumina, cerium oxide, and carbon black, and polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic silica is preferred. The external additive may be used alone or in combination with two or more kinds. In addition, two or more kinds of hydrophobic silica having different particle sizes may be used. When the toner particles are surface-treated 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 preferably 5 parts by mass or less, more preferably 4.5 parts by mass or less, and even more preferably 4 parts by mass or less, relative to 100 parts by mass of the toner particles.

[0100] Toners are used for developing electrostatic images in electrophotographic printing. The toners can be used, for example, as one-component developers or mixed with a carrier to form two-component developers. EXAMPLES

[0101] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Each property value was measured and evaluated by the following methods. In the notation "alkylene oxide (X)" and the like, the number X in parentheses means the average number of moles of alkylene oxide added.

[0102] <Measurement method> [Softening point, crystallinity index, melting point and glass transition temperature of resin] (1) Softening point Using a flow tester "CFT-500D" (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 the plunger, and extruding the sample from a nozzle with a diameter of 1 mm and a length of 1 mm. The plunger descent amount of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was taken as the softening point. (2) Crystallinity index Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of sample was weighed into an aluminum pan and cooled to 0°C at a rate of 10°C / min. The sample was then left to stand for 1 minute, after which it was heated to 180°C at a rate of 10°C / min and the calorific value was measured. The temperature of the peak with the largest peak area among the observed endothermic peaks was taken as the endothermic maximum peak temperature (1), and the crystallinity index was calculated by (softening point (°C)) / (endothermic maximum peak temperature (1) (°C)). (3) Melting point and glass transition temperature Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and cooled to 0°C at a rate of 10°C / min. The sample was then heated at a rate of 10°C / min, and the amount of heat was measured. The temperature of the peak with the largest peak area among the endothermic peaks observed was taken as the maximum endothermic peak temperature (2). In the case of a crystalline resin, the peak temperature was taken as the melting point. In the case of an amorphous resin, when a peak was observed, the temperature of the peak was taken, and when a step was observed without a peak, the temperature of the intersection of the tangent showing the maximum slope of the curve of the step and the extension of the baseline on the low temperature side of the step was taken as the glass transition temperature.

[0103] [Acid value of resin] The acid value of the resin was measured according to the neutralization titration method described in JIS K 0070: 1992. The measurement solvent was a mixed solvent of acetone and toluene (acetone:toluene=1:1 (volume ratio)).

[0104] [Melting point of release agent] Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and then cooled from 200°C to 0°C at a rate of 10°C / min. The sample was then heated at a rate of 10°C / min, the calorific value was measured, and the maximum endothermic peak temperature was taken as the melting point.

[0105] [Volume median particle diameter D of resin particles, colorant particles, and release agent particles 50 and CV value] (1) Measuring device: Laser diffraction type particle size measuring device "LA-920" (manufactured by Horiba Ltd.) (2) Measurement conditions: Put the sample dispersion in a measurement cell, add distilled water, and measure the volume median particle size D at a concentration where the absorbance is in the appropriate range. 50 The volume average particle diameter Dv was measured, and the CV value was calculated according to the following formula. CV value (%) = (Standard deviation of particle size distribution / Volume average particle size Dv) x 100

[0106] [Solid Content Concentration of Resin Particle Dispersion, Colorant Particle Dispersion, and Release Agent Particle Dispersion] Using an infrared moisture meter "FD-230" (Kett Electric Laboratory Co., Ltd.), the moisture content (mass%) of 5 g of the measurement sample was measured at a drying temperature of 150°C and measurement mode 96 (monitoring time 2.5 minutes, moisture content fluctuation range 0.05%). The solid content concentration was calculated according to the following formula. Solid concentration (mass%) = 100-moisture (mass%)

[0107] [Volume median particle diameter of agglomerated particles D 50 〕 Volume median particle size of agglomerated particles D 50 was measured as follows: Measuring instrument: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.) Aperture diameter: 50μm Analysis software: "Multisizer (registered trademark) III version 3.51" (Beckman Coulter, Inc.) Electrolyte: "Isoton (registered trademark) II" (manufactured by Beckman Coulter, Inc.) Measurement conditions: The sample dispersion is added to 100 mL of the electrolyte to adjust the concentration so that the particle size of 30,000 particles can be measured in 20 seconds. Then, 30,000 particles are measured again, and the volume median particle size D is calculated from the particle size distribution. 50 asked for.

[0108] [Circularity of fused particles] The circularity of the fused particles was measured under the following conditions. Measurement equipment: Flow-type particle image analyzer "FPIA-3000" (Sysmex Corporation) Preparation of dispersion: A dispersion of fused particles was prepared by diluting with deionized water to a solids concentration of 0.001 to 0.05% by mass. Measurement mode: HPF measurement mode

[0109] [Volume median particle size of toner particles D 50 and CV value] Volume median particle size of toner particles D 50 was measured as follows: The measurement device, aperture diameter, analysis software, and electrolyte were determined based on the volume median particle diameter D 50 The same one used in the measurement was used. Dispersion: Polyoxyethylene lauryl ether "EMULGEN (registered trademark) 109P" (manufactured by Kao Corporation, HLB (hydrophile-lipophile balance) = 13.6) was dissolved in the electrolyte to obtain a dispersion with a concentration of 5 mass %. Dispersion conditions: 10 mg of a measurement sample of dried toner particles was added to 5 mL of the dispersion liquid, and dispersed for 1 minute using an ultrasonic disperser. Thereafter, 25 mL of the electrolyte was added, and the mixture was further dispersed for 1 minute using an ultrasonic disperser to prepare a sample dispersion liquid. Measurement conditions: The sample dispersion is added to 100 mL of the electrolyte to adjust the concentration so that the particle size of 30,000 particles can be measured in 20 seconds. Then, 30,000 particles are measured and the volume median particle size D is calculated from the particle size distribution. 50 and volume average particle size D V asked for. The CV value (%) was calculated according to the following formula. CV value (%) = (Standard deviation of particle size distribution / Volume average particle size D V ) x 100

[0110] [Production of amorphous polyester resin] Production Example A1 (Production of Resin A-1) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 4367g of propylene oxide (2.2) adduct of bisphenol A, 1098g of terephthalic acid, 32g of tin (II) di(2-ethylhexanoate), and 3.2g of gallic acid (3,4,5-trihydroxybenzoic acid) were added. The reaction system was heated to 235°C under a nitrogen atmosphere while stirring, and then maintained at 235°C for 5 hours. The pressure in the flask was then reduced and maintained at 8kPa for 1 hour. After that, the pressure was returned to atmospheric pressure, and the mixture was cooled to 160°C. While maintaining the temperature at 160°C, a mixture of 1070g of styrene, 267g of stearyl methacrylate, 144g of acrylic acid, and 160g of dibutyl peroxide was added dropwise to the reaction system over 3 hours. The reaction system was then held at 160°C for 30 minutes, then heated to 200°C, and the pressure in the flask was further reduced and held at 8kPa for 1 hour. After that, the pressure was returned to atmospheric pressure, and the mixture was cooled to 190°C, and 174g of fumaric acid, 378g of sebacic acid, 240g of trimellitic anhydride, and 3.2g of 4-tert-butylcatechol were added, and the temperature was raised to 210°C at 10°C / hr, and the reaction was continued at 4kPa until the desired softening point was obtained, to obtain Resin A-1. The physical properties are shown in Table 1.

[0111] Production Examples A2 and A3 (Production of Resins A-2 and A-3) Resins A-2 and A-3 were obtained in the same manner as in Production Example A1, except that the amount of raw material monomer for the polyester resin segment and the type and amount of raw material monomer for the addition polymerization segment were changed as shown in Table 1. The physical properties are shown in Table 1.

[0112] Production Example A'4 (Production of Resin A'-4) Resin A'-4 was obtained in the same manner as in Production Example A1, except that the amount of raw material monomer for the polyester resin segment and the type and amount of raw material monomer for the addition polymerization segment were changed as shown in Table 1. The physical properties are shown in Table 1.

[0113] Production Example A'5 (Production of Resin A'-5) The raw monomers of polyester resin except trimellitic anhydride shown in Table 1 were placed in a 10 L stainless steel kettle equipped with a nitrogen inlet tube, a dehydration tube, a stirrer and a thermocouple. The mixture was reacted at 230°C for 8 hours under a nitrogen atmosphere, and then reacted under a reduced pressure of 1.3 kPa to 2.0 kPa for 4 hours. After adding trimellitic anhydride, the mixture was reacted at 180°C until the desired softening point was reached, to obtain Resin A'-5. The physical properties are shown in Table 1.

[0114] Manufacturing Example B1 (Manufacturing of Resin B-1) In a 10 L stainless steel kettle equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple, the raw material monomers of the polyester resin, except for trimellitic anhydride, shown in Table 1, were placed. The mixture was reacted at 230°C for 8 hours under a nitrogen atmosphere, and then reacted under a reduced pressure of 1.3 kPa to 2.0 kPa for 4 hours. After adding trimellitic anhydride, the mixture was reacted at 180°C until the desired softening point was reached, yielding Resin B-1. The physical properties are shown in Table 1.

[0115] Manufacturing Example D1 (Manufacturing of Resin D-1) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3450g of a propylene oxide (2.2) adduct of bisphenol A, 655g of terephthalic acid, 24g of tin (II) di(2-ethylhexanoate), and 2.4g of gallic acid (3,4,5-trihydroxybenzoic acid) were added, and the reaction system was heated to 235°C while stirring under a nitrogen atmosphere, and then maintained at 235°C for 5 hours, after which the pressure in the flask was reduced and maintained at 8kPa for 1 hour. After that, the pressure was returned to atmospheric pressure, and then cooled to 160°C, and a mixture of 2133g of styrene, 533g of stearyl methacrylate, 114g of acrylic acid, and 320g of dibutyl peroxide was added dropwise over 3 hours while maintaining the temperature at 160°C. The reaction system was then held at 160°C for 30 minutes, then heated to 200°C, and the pressure in the flask was further reduced and held at 8kPa for 1 hour. After that, the pressure was returned to atmospheric pressure, and the mixture was cooled to 190°C, 582g of succinic acid was added, and the mixture was heated to 210°C at 10°C / hr, and then reacted at 4kPa until the desired softening point was reached, yielding Resin D-1. The physical properties are shown in Table 1.

[0116] [Table 1]

[0117] [Production of crystalline polyester resin] Manufacturing Example C1 (Manufacturing of Resin C-1) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer and a thermocouple was replaced with nitrogen, and the raw material monomers of the polyester resin shown in Table 2 were added. The reaction system was heated to 135°C while stirring, and then held at 135°C for 3 hours, and then heated from 135°C to 200°C over 10 hours. Then, 10g of tin(II) di(2-ethylhexanoate) was added to the reaction system, and the system was further held at 200°C for 1 hour, after which the pressure in the flask was reduced and the system was held under a reduced pressure of 8kPa for 1 hour to obtain Resin C-1, a crystalline polyester resin. The physical properties are shown in Table 2.

[0118] Production Examples C2 to C5 (Production of Resins C-2 to C-5) Resins C-2 to C-5 were obtained in the same manner as in Production Example C1, except that in Production Example C1, the types and amounts of raw material monomers for the polyester resin were changed as shown in Table 2. Table 2 shows the physical property values.

[0119] Production Example C'6 (Production of Resin C'-6) Resin C'-6 was obtained in the same manner as in Production Example C1, except that in Production Example C1, the types and amounts of raw material monomers for the polyester resin were changed as shown in Table 2. The physical property values ​​are shown in Table 2.

[0120] [Table 2]

[0121] Production Example X1 (Production of Resin Particle Dispersion X-1) In a 3 L vessel equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen inlet tube, 350 g of amorphous polyester resin A-1, 150 g of crystalline polyester resin C-1, and 500 g of methyl ethyl ketone were placed and dissolved for 2 hours at 73° C. A 5% by mass aqueous solution of sodium hydroxide was added to the resulting solution so that the degree of neutralization with respect to the acid value of the resin was 60 mol%, and the mixture was stirred for 30 minutes. Next, while maintaining the temperature at 73°C, 1000g of deionized water was added over 60 minutes while stirring at 200 r / min to cause phase inversion emulsification. While maintaining the temperature at 73°C, the methyl ethyl ketone was distilled off under reduced pressure to obtain a dispersion. Thereafter, while continuing to stir, the dispersion was cooled to 30°C, and deionized water was added so that the solid concentration became 25% by mass, thereby obtaining resin particle dispersion X-1. The physical properties are shown in Table 3.

[0122] Production Examples X2 to X8 (Production of Resin Particle Dispersions X-2 to X-8) Resin particle dispersions X-2 to X-8 were obtained in the same manner as in Production Example X1, except that the amorphous polyester resin and the crystalline polyester resin were changed as shown in Table 3. Table 3 shows the physical property values.

[0123] Production Example X9 (Production of Resin Particle Dispersion X-9) Resin particle dispersion X-9 was obtained in the same manner as in Production Example X1, except that the amount of amorphous polyester resin A-1 was changed to 400 g and the amount of crystalline polyester resin C-1 was changed to 100 g. The physical properties are shown in Table 3.

[0124] Manufacturing Example X10 (Manufacturing of Resin Particle Dispersion X-10) Resin X-10 was obtained in the same manner as in Production Example X1, except that the amount of amorphous polyester resin A-1 was changed to 450 g and the amount of crystalline polyester resin C-1 was changed to 50 g. The physical properties are shown in Table 3.

[0125] Production Examples X'11 to X'13 (Production of Resin Particle Dispersions X'-11 to X'-13) Resin particle dispersions X'-11 to X'-13 were obtained in the same manner as in Production Example X1, except that the amorphous polyester resin and the crystalline polyester resin were changed as shown in Table 3. Table 3 shows the physical property values.

[0126] Production Example Y1 (Production of Resin Particle Dispersion Y-1) 500 g of Resin B-1 and 500 g of methyl ethyl ketone were placed in a 3 L vessel equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen inlet tube, and dissolved for 2 hours at 73° C. A 5% by mass aqueous solution of sodium hydroxide was added to the resulting solution so that the degree of neutralization with respect to the acid value of Resin B-1 was 60 mol%, and the mixture was stirred for 30 minutes. Next, while maintaining the temperature at 73°C, 1000g of deionized water was added over 60 minutes while stirring at 200r / min (circumferential speed 63m / min) to cause phase inversion emulsification. While maintaining the temperature at 73°C, the methyl ethyl ketone was distilled off under reduced pressure to obtain a dispersion. Thereafter, while continuing to stir, the dispersion was cooled to 30°C, and deionized water was added so that the solid concentration became 25% by mass, thereby obtaining resin particle dispersion Y-1. The physical properties are shown in Table 3.

[0127] Production Example P1 (Production of Resin Particle Dispersion P-1) Resin particle dispersion P-1 was obtained in the same manner as in Production Example Y1, except that Resin B-1 was changed to Resin D-1. Physical property values ​​are shown in Table 3.

[0128] [Table 3]

[0129] Production Example W1 (Production of Release Agent Particle Dispersion W-1) Into a 1 L beaker, 120 g of deionized water, 86 g of resin particle dispersion P-1, and 40 g of paraffin wax "HNP-9" (manufactured by Nippon Seiro Co., Ltd., melting point 75°C) were added, and the mixture was melted by maintaining the temperature at 90 to 95°C and stirred to obtain a molten mixture. The obtained molten mixture was dispersed for 20 minutes using an ultrasonic homogenizer "US-600T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.) while maintaining the temperature at 90 to 95°C, and then cooled to room temperature (20°C). Deionized water was added to the obtained dispersion to adjust the solid content to 20 mass%, thereby obtaining release agent particle dispersion W-1. The volume median particle diameter D of the release agent particles in release agent particle dispersion W-1 was 50 The diameter was 0.47 μm and the CV value was 27%.

[0130] Production Example W2 (Production of Release Agent Particle Dispersion W-2) Release agent particle dispersion W-2 was obtained in the same manner as in Production Example W1, except that the type of release agent was changed to Fischer-Tropsch wax "FNP-00 90" (manufactured by Nippon Seiro Co., Ltd., melting point 90°C). 50 The diameter was 0.45 μm and the CV value was 28%.

[0131] Production Example E1 (Production of Colorant Particle Dispersion E-1) In a 1 L beaker, 100 g of copper phthalocyanine pigment "ECB-301" (manufactured by Dainichiseika Chemicals Co., Ltd.), 35 g of polyoxyethylene (13) distyrenated phenyl ether "Emulgen A-60" (manufactured by Kao Corporation, nonionic surfactant), and 300 g of deionized water were mixed and dispersed for 1 hour at room temperature (20°C) with a stirring blade rotation speed of 8000 rpm using a homomixer "TKAGI HOMOMIXER 2M-03" (manufactured by Tokushu Kika Kogyo Co., Ltd.), and then the mixture was treated for 15 passes at a pressure of 150 MPa using a "Microfluidizer M-110EH" (manufactured by Microfluidics Co., Ltd.), and then passed through a 200 mesh filter. Deionized water was added so that the solid concentration was 20 mass%, to obtain a colorant particle dispersion E-1. The volume median particle diameter D of the obtained colorant particles was 50 The thickness was 0.12 μm and the CV value was 21%.

[0132] [Toner manufacturing] Example 1 (Production of Toner 1) Into a 3 L four-neck flask equipped with a dehydration tube, a stirrer, and a thermocouple, 500 g of resin particle dispersion X-1, 49 g of release agent particle dispersion W-1, 49 g of release agent particle dispersion W-2, and 63 g of colorant particle dispersion E-1 were added and mixed at a temperature of 25° C. Next, while stirring the mixture, a solution obtained by dissolving 40 g of ammonium sulfate in 570 g of deionized water and adding a 4.8 mass % potassium hydroxide aqueous solution to adjust the pH to 8.2 was added dropwise over 10 minutes at 25° C., and the temperature was then raised to 58° C. over 2 hours to measure the volume median particle diameter D of the aggregated particles. 50 The temperature was maintained at 58° C. until the particle size reached 6.5 μm, thereby obtaining a dispersion of aggregated particles 1. The obtained dispersion of aggregated particles 1 was cooled to 55° C., and while maintaining the temperature at 55° C., 48 g of resin particle dispersion Y-1 was added over 90 minutes, thereby obtaining a dispersion of aggregated particles 2 in which resin particles were aggregated to aggregated particles 1. To the obtained dispersion liquid of aggregated particles 2, 50 g of sodium salt of naphthalenesulfonic acid formalin condensate "DEMOL MS" (manufactured by Kao Corporation, effective concentration 20% by mass) and 1500 g of deionized water were added. Thereafter, the temperature was raised to 75°C over 1 hour, and the temperature was maintained at 75°C until the circularity reached 0.970, thereby obtaining a dispersion liquid of fused particles in which aggregated particles 2 were fused. The obtained dispersion of fused particles was cooled to 30°C, and the solid content was separated by suction filtration, washed with deionized water at 25°C, and then suction filtered at 25°C for 2 hours. The solid content was then vacuum dried at 33°C for 24 hours using a vacuum constant temperature dryer "DRV622DA" (manufactured by ADVANTEC Corporation), to obtain toner particles having a core-shell structure. The physical properties of the toner particles are shown in Table 4. 100 parts by mass of toner particles, 2.5 parts by mass of hydrophobic silica "RY50" (manufactured by Nippon Aerosil Co., Ltd., number average particle size: 0.04 μm), and 1.0 part by mass of hydrophobic silica "Cabosil (registered trademark) TS720" (manufactured by Cabot Japan Co., Ltd., number average particle size: 0.012 μm) were placed in a Henschel mixer and stirred, and the mixture was passed through a 150 mesh sieve to obtain toner 1.

[0133] <Toner Evaluation> The obtained toner 1 was evaluated as follows.

[0134] [Evaluation of electrostatic charge] At a temperature of 25°C and a relative humidity of 50%, 2.1 g of toner and 27.9 g of silicone ferrite carrier (manufactured by Kanto Denka Kogyo Co., Ltd., average particle size: 40 μm) were placed in a 50 mL cylindrical polypropylene bottle (manufactured by Nikko Hansen Co., Ltd.) and mixed at 250 r / min using a ball mill. Immediately after mixing, the charge amount was measured under the following conditions using a "q / m-meter" (manufactured by Epping Co., Ltd.). The evaluation results are shown in Table 4. Mesh size: 635 mesh (opening: 24 μm, stainless steel) Soft blow: Blow pressure (1000V) ·Suction time: 90 seconds The charge amount is calculated by the following formula, and a larger absolute value indicates better chargeability. Charge amount (μC / g) = Total charge after 90 seconds (μC) / Amount of toner absorbed (g)

[0135] [Evaluation of Fog] The toner was mounted on a commercially available printer "Microline (registered trademark) 5400" (manufactured by Oki Electric Industry Co., Ltd.), and an image with a print density of 1% was printed on high-quality paper "J paper A4 size" (manufactured by Fuji Xerox Co., Ltd.) in an environment of a temperature of 25°C and a relative humidity of 50%. This was repeated to print a total of 1000 sheets, and then a blank sheet was printed, during which the printer was stopped in the middle of printing the blank sheet. The developing unit was removed from the printer, and "Scotch (registered trademark) Mending Tape 810" (manufactured by 3M Japan Ltd., width: 18 mm) was attached to the photoconductor, and the toner on the photoconductor was peeled off with the tape. The tape peeled off from the photoreceptor and unused tape were attached to high-quality paper "J paper A4 size" (manufactured by Fuji Xerox Co., Ltd.), and the tape peeled off from the photoreceptor and unused tape were each measured using a colorimeter "SpectroEye" (manufactured by GretagMacbeth, 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 unused tape was taken as fog. The smaller the fog value, the better the image without fog. The evaluation results are shown in Table 4.

[0136] Examples 2 to 10, Comparative Examples 1 to 3 (Preparation of toners 2 to 13) Toners 2 to 13 were obtained in the same manner as in Example 1, except that the resin particle dispersion was changed as shown in Table 4. The physical property values ​​of the obtained toner particles and the evaluation results of Toners 2 to 13 are shown in Table 4.

[0137] [Table 4]

[0138] The toner obtained by the manufacturing method of the present invention using an amorphous polyester resin A including a polyester resin segment and an addition polymerization resin segment containing a structural unit derived from a vinyl monomer having a hydrocarbon group having from 9 to 24 carbon atoms, and a crystalline polyester resin C including a structural unit derived from a monoalcohol having a hydrocarbon group having from 9 to 24 carbon atoms and / or a structural unit derived from a monocarboxylic acid having a hydrocarbon group having from 9 to 24 carbon atoms, has excellent charging properties and sufficiently suppresses the occurrence of fogging (Examples 1 to 10). In contrast, when resin A defined in the present invention was used together with resin C containing neither a monoalcohol-derived structural unit nor a monocarboxylic acid-derived structural unit (Comparative Example 1), when an amorphous polyester resin containing a structural unit derived from a vinyl monomer having a hydrocarbon group having 8 carbon atoms was used together with resin C defined in the present invention (Comparative Example 2), and when an amorphous polyester resin not containing an addition polymerization segment was used together with resin C defined in the present invention (Comparative Example 3), all of the following results showed poor electrostatic properties and the occurrence of fogging was not sufficiently suppressed.

Claims

1. A method for producing a toner for developing electrostatic images, comprising a step of aggregating and a step of fusing resin particles, the resin particles containing an amorphous resin and a crystalline resin in the same or different particles, in an aqueous medium, the method comprising: the amorphous resin contains an amorphous polyester-based resin A including a polyester resin segment and an addition polymerization resin segment containing a structural unit derived from a vinyl monomer having a hydrocarbon group having from 9 to 24 carbon atoms; The crystalline resin contains a crystalline polyester resin C containing a structural unit derived from a monoalcohol having a hydrocarbon group having from 9 to 24 carbon atoms and / or a structural unit derived from a monocarboxylic acid having a hydrocarbon group having from 9 to 24 carbon atoms. A method for producing a toner for developing electrostatic images.

2. 2. The method for producing a toner for developing electrostatic images according to claim 1, wherein the amorphous polyester resin A comprises a polyester resin segment and an addition polymerization resin segment containing a structural unit derived from a vinyl monomer having a hydrocarbon group having from 15 to 24 carbon atoms.

3. The method for producing a toner for developing electrostatic images according to claim 1 , wherein the crystalline polyester resin C contains a structural unit derived from ethylene glycol.

4. 2. The method for producing a toner for developing electrostatic images according to claim 1, wherein the content of structural units derived from vinyl monomers having a hydrocarbon group having from 9 to 24 carbon atoms in the amorphous polyester resin A is from 1% by mass to 10% by mass.

5. 5. The method for producing a toner for developing electrostatic images according to claim 1, wherein the crystalline polyester resin C contains, in total, 0.2 mol % or more and 20 mol % or less of the structural units derived from an alcohol having a hydrocarbon group having from 9 to 24 carbon atoms and the structural units derived from a monocarboxylic acid having a hydrocarbon group having from 9 to 24 carbon atoms.