WO2024128226A1

WO2024128226A1 - Toner for static charge image development and method for manufacturing same

Info

Publication number: WO2024128226A1
Application number: PCT/JP2023/044449
Authority: WO
Inventors: 泰輝山本; 寛人林; 丈士平井; 裕司丸野; 将一村田
Original assignee: 花王株式会社
Priority date: 2022-12-12
Filing date: 2023-12-12
Publication date: 2024-06-20
Also published as: JP2024084148A

Abstract

The present invention relates to toner for static charge image development, the toner containing a crystalline polyester resin C, an amorphous polyester-based resin A, and a coloring agent. The crystalline polyester resin C includes a constitutional unit that is derived from an aliphatic diol component containing ethylene glycol, and a constitutional unit that is derived from an aliphatic dicarboxylic acid component having a carbon number of 10 to 14. The crystalline polyester resin C has an ester group concentration of 6.5 mmol/g to 9.0 mmol/g. The coloring agent is a pigment having an NH group amount of 6.0 mmol/g or greater, the NH group amount being a value that is the total number of -NH- and -NH₂ per molecule divided by the molecular weight.

Description

Toner for developing electrostatic images and method for producing the same

The present invention relates to a toner for developing electrostatic images used to develop latent images formed in electrophotography, electrostatic recording, electrostatic printing, etc., and a method for producing the same.

With the diversification of print media, there is an increasing demand for electrophotographic printing on print media other than paper. Major media include plastic films such as polyethylene terephthalate film, polypropylene film, and polyethylene film, which are used for PET bottle labels and various packages. Since these plastic films have a smooth surface, the anchor effect between the surface and the coating film (printed coating film) formed by printing electrophotographic toner on the surface is difficult to work, and the printed coating film is easily peeled off from the plastic film. In addition, since these plastic films are sensitive to heat, the print media curls and shrinks when electrophotographic toner is thermally fixed.
Patent Document 1 (JP 2022-54448 A) discloses an image forming method for a polypropylene film or a polyethylene film, which is excellent in image density of the obtained image and further has excellent abrasion resistance of the image. The method is a method of forming an image on a polypropylene film or a polyethylene film by a toner containing a crystalline polyester resin C in a binder resin, and the SP value of the crystalline polyester resin C is 9.0 or more and 10.1 or less, the content of the crystalline polyester resin C in the binder resin is 10% by mass or more and 60% by mass or less, the surface tension of the printed surface of the polypropylene film or polyethylene film is 35 mN / m or more and 49 mN / m or less, and the fixing temperature is 5 ° C. higher than the melting point of the polypropylene film or polyethylene film. An image forming method is disclosed.
Patent Document 2 (JP 2020-60687 A) contains an amorphous polyester resin and a crystalline polyester resin, and the amorphous polyester resin is a polycondensate of an alcohol component (A-al) and a carboxylic acid component (A-ac) containing succinic acid or its anhydride substituted with a linear aliphatic hydrocarbon group having 16 to 18 carbon atoms, and the crystalline polyester resin is a polycondensate of an alcohol component (C-al) and a carboxylic acid component (C-ac), and the alcohol component (C-al) is a monoalcohol having 6 to 24 carbon atoms, and the carboxylic acid component (C-ac) is at least one selected from the group consisting of a monocarboxylic acid having 6 to 24 carbon atoms. It is disclosed that a toner for developing an electrostatic image has excellent low-temperature fixability and heat-resistant storage stability of the toner, and excellent storage stability of printed matter.

The present invention relates to the following [1] and [2].
[1] A toner for developing electrostatic images, comprising a crystalline polyester resin C, an amorphous polyester resin A, and a colorant,
the crystalline polyester resin C contains a structural unit derived from an aliphatic diol component containing ethylene glycol and a structural unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, and has an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g,
The colorant is a pigment having an NH group amount of 6.0 mmol/g or more when the total number of -NH- and _-NH2 groups in one molecule is divided by the molecular weight to define the NH group amount.
Toner for developing electrostatic images.
[2] A method for producing a toner for developing an electrostatic image, comprising a step of aggregating and fusing resin particles, the resin particles including a crystalline polyester resin C and an amorphous polyester resin A in the same or different particles, and a colorant in an aqueous medium, the method comprising the steps of:
the crystalline polyester resin C contains a structural unit derived from an aliphatic diol component containing ethylene glycol and a structural unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, and has an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g,
The colorant is a pigment having an NH group amount of 6.0 mmol/g or more when the total number of -NH- and _-NH2 groups in one molecule is divided by the molecular weight to define the NH group amount.
A method for producing a toner for developing electrostatic images.

Detailed Description of the Invention

Printed packaging materials such as PET bottle labels and packaging films are required to have high robustness in terms of protecting the quality of the contents and displaying information. In the printed coating film formed using the printing ink for printed packaging materials, the coating film hardness is evaluated by a pencil hardness test, and a pencil hardness of B or higher is required. The inventors have studied and found that the printed packaging materials obtained by forming a printed coating film on a printing medium such as a plastic film using the image forming method described in Patent Document 1 and the toner for developing an electrostatic image described in Patent Document 2 have robustness to a tape peeling test and a fingernail rubbing test, but robustness to a pencil hardness test needs to be improved. In addition, in order to suppress the thermal shrinkage of a printing medium such as a plastic film, the toner is required to have low-temperature fixability.
The present invention relates to a toner for developing electrostatic images, which has excellent low-temperature fixing properties and is capable of forming a printing coating film with high fastness on a printing medium (substrate) such as a plastic film, and a method for producing the same.

The present inventors have found that a toner for developing electrostatic images, which contains a crystalline polyester resin C, an amorphous polyester resin A, and a colorant, in which the crystalline polyester resin C contains a constituent unit derived from an aliphatic diol component containing ethylene glycol and a constituent unit derived from an aliphatic dicarboxylic acid component having 10 to 14 carbon atoms and has an ester group concentration in a specific range, and the colorant is a pigment in which the amount of NH groups is controlled to a specific value or more, has excellent low-temperature fixing properties, and can form a printed coating film with high robustness using the toner.

The present invention provides a toner for developing electrostatic images that has excellent low-temperature fixing properties and can form a highly durable printing coating film on a printing medium (substrate) such as a plastic film, and a method for producing the same.

[Toner for developing electrostatic images]
The toner for developing electrostatic images (hereinafter also simply referred to as "toner") of the present invention contains at least a crystalline polyester resin C (hereinafter also simply referred to as "resin C"), an amorphous polyester resin A (hereinafter also simply referred to as "resin A"), and a colorant.
The crystalline polyester resin C contains a constituent unit derived from an aliphatic diol component containing ethylene glycol and a constituent unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, and has an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g. The colorant is a pigment having an NH group amount of 6.0 mmol/g or more, when the NH group amount is the value obtained by dividing the total number of -NH- and _-NH2 in one molecule by the molecular weight.
Due to the above-mentioned characteristics, the toner of the present invention has excellent low-temperature fixing properties, and the toner can provide a printed coating film having high fastness.
In addition, toner particles containing at least resin C, resin A, and a colorant (hereinafter, also simply referred to as "toner particles") can be used as they are as the toner of the present invention, but it is preferable to use the toner particles after adding a fluidizing agent or the like as an external additive to the surface of the toner particles.

The reason why the toner of the present invention has excellent low-temperature fixability and can provide a printed coating film with excellent fastness is not clear, but is thought to be as follows.
The toner of the present invention contains a structural unit derived from an aliphatic diol component containing ethylene glycol in the crystalline polyester resin C, and thus allows two adjacent ester groups to be arranged, which has high cohesive force and allows crystal nuclei to be generated quickly, so that the crystal size does not increase during toner particle formation and the crystal domains are finely dispersed.Then, during fixing, the polarity is increased by the adjacent ester groups, which improves compatibility with the amorphous polyester resin A and allows the toner to melt quickly, which is thought to result in excellent low-temperature fixing properties.
In addition, as a result of the study by the present inventors, it was found that the hardness of the printed coating film itself is important in order to improve the fastness of the printed coating film formed on a substrate such as a plastic film in a pencil hardness test. This is believed to be because a strong force is applied locally when the coating film is scraped with a pencil having a sharp tip. In the toner of the present invention, the crystalline polyester resin C contained in the toner contains a constitutional unit derived from an aliphatic diol component containing ethylene glycol and a constitutional unit derived from an aliphatic dicarboxylic acid component having 10 to 14 carbon atoms, and the ester group concentration is 6.5 mmol/g to 9.0 mmol/g, thereby ensuring the cohesive force of the crystalline polyester resin C after the coating film is formed, while improving the compatibility with the amorphous polyester resin A, and forming a state in which the crystal domains of the crystalline polyester resin C are finely dispersed in the printed coating film. Furthermore, since the NH group amount of the pigment as a colorant is 6.0 mmol/g or more, the ester group in the crystalline polyester resin C and the NH group contained in the pigment effectively interact with each other, and the recrystallization of the crystalline polyester resin C after the coating film is formed is promoted. As a result, it is believed that the cohesive force of the crystalline polyester resin C in the printed coating film is significantly improved, leading to an increase in the hardness of the printed coating film and an improvement in fastness.

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. A non-crystalline resin is one in which no endothermic peak is observed, or if an endothermic peak is observed, the crystallinity index is less than 0.6 or more than 1.4. The crystallinity index can be appropriately adjusted by the type and ratio of raw material monomers, as well as production conditions such as reaction temperature, reaction time, and cooling rate.
With respect to hydrocarbon groups, the references "(iso or tertiary)" and "(iso)" in parentheses refer to both the cases with and without the presence of these prefixes; the absence of these prefixes indicates normal.
The term "(meth)acrylic acid" refers to at least one selected from acrylic acid and methacrylic acid.
By "styrenic compound" is meant unsubstituted or substituted styrene.

[Toner Particles]
In the present invention, the toner particles contain at least a crystalline polyester resin C (hereinafter also simply referred to as "resin C"), an amorphous polyester resin A (hereinafter also simply referred to as "resin A"), and a colorant.

<Crystalline Polyester Resin C>
Resin C is used as a binder resin for toner, and from the viewpoint of low-temperature fixability of the toner and robustness of the printed coating film, is a polycondensate containing, as a constituent unit derived from an aliphatic diol component containing ethylene glycol, a constituent unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, as a constituent unit derived from a carboxylic acid component, and having an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g. The following alcohol components and carboxylic acid components may be used alone or in combination of two or more.

The aliphatic diol component contains ethylene glycol, and may contain an aliphatic diol other than ethylene glycol.
Examples of aliphatic diols other than ethylene glycol include 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 2-butene-1,4-diol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, neopentyl glycol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, and 1,12-dodecanediol.

The amount of the aliphatic diol component 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, even more preferably 100 mol%.
The amount of the aliphatic diol component in the alcohol component is the same as the content of the structural units derived from the aliphatic diol component in the structural units derived from the alcohol component. The same applies to the following explanation of the amount of each component of the resin.

The amount of ethylene glycol in the aliphatic diol 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%.
The amount of ethylene glycol in the alcohol component is preferably 65 mol% or more, more preferably 85 mol% or more, even more preferably 90 mol% or more, still more preferably 95 mol% or more, and is 100 mol% or less, preferably 100 mol%.

The alcohol component may contain other alcohol components different from the aliphatic diol component. Examples of other alcohol components include alkylene oxide adducts of aromatic diols, such as alkylene oxide adducts of bisphenol A; and trihydric or higher alcohols, such as glycerin, pentaerythritol, and trimethylolpropane.

The number of carbon atoms of the aliphatic dicarboxylic acid is 14 or less from the viewpoint of low-temperature fixing property of the toner and fastness of the printed coating film, and from the same viewpoint, is 10 or more, preferably 12 or more. The aliphatic dicarboxylic acid is preferably an α,ω-straight-chain aliphatic dicarboxylic acid.
Specific examples of aliphatic dicarboxylic acids having 10 to 14 carbon atoms include one or more selected from sebacic acid, 1,11-undecanedioic acid, 1,12-dodecanedioic acid, 1,13-tridecanedioic acid, and 1,14-tetradecanedioic acid. Among these, from the viewpoints of the low-temperature fixing property of the toner and the fastness of the printed coating film, one or more selected from sebacic acid, 1,12-dodecanedioic acid, and 1,14-tetradecanedioic acid are more preferred, and one or more selected from 1,12-dodecanedioic acid and 1,14-tetradecanedioic acid are even more preferred.
The amount of the aliphatic dicarboxylic acid having 10 or more and 14 or less carbon atoms in the carboxylic acid component is preferably 70 mol % or more, more preferably 75 mol % or more, even more preferably 80 mol % or more, and even more preferably 85 mol % or more, and is 100 mol % or less, preferably 95 mol % or less.

From the viewpoints of low-temperature fixability of the toner and fastness of the printed coating film, the carboxylic acid component preferably contains a monocarboxylic acid component having a carbon number of 6 to 24. From the same viewpoints, the carbon number of the monocarboxylic acid component is 6 or more, preferably 8 or more, more preferably 12 or more, even more preferably 14 or more, still more preferably 16 or more, and is 24 or less, preferably 22 or less, more preferably 20 or less.
Examples of monocarboxylic acids having 6 to 24 carbon atoms include caprylic acid, pelargonic acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, etc. Among these, preferred are caprylic acid, lauric acid, stearic acid, and behenic acid, and from the viewpoint of obtaining a printing coating film having high low-temperature fixability and fastness, more preferred are stearic acid and behenic acid, and even more preferred is stearic acid.
The amount of monocarboxylic acid having 6 to 24 carbon atoms in the carboxylic acid component is preferably 1 mol % or more, more preferably 5 mol % or more, even more preferably 7 mol % or more, and is preferably 35 mol % or less, more preferably 30 mol % or less, even more preferably 20 mol % or less, even more preferably 15 mol % or less.
The carboxylic acid component may contain another carboxylic acid component other than the aliphatic dicarboxylic acid having from 10 to 14 carbon atoms and the monocarboxylic acid having from 6 to 24 carbon atoms. Examples of the other carboxylic acid component include aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid; and trivalent or higher polyvalent carboxylic acids such as trimellitic acid.

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.

From the viewpoint of the low-temperature fixing property of the toner and the robustness of the printed coating film, the ester group concentration of resin C is 6.5 mmol/g or more and 9.0 mmol/g or less, preferably 6.7 mmol/g or more, and preferably 8.8 mmol/g or less, more preferably 8.6 mmol/g or less. The ester group concentration of resin C is calculated by the following formula.

(In the formula, A is the total amount (mol) of ester bonds produced when all the raw material monomers of the crystalline polyester resin C are reacted, and B is the total mass (g) of the raw material monomers constituting the crystalline polyester resin C. The numbers in parentheses in the formula indicate the units of each value.)
When two or more resins are mixed and used as the crystalline polyester resin C, the weighted average of the ester group concentrations of the crystalline polyester resin C is defined as the ester group concentration of the crystalline polyester resin C. When the crystalline polyester resin C is a composite resin, B is defined as the total mass (g) of the raw material monomers of the constituent portion derived from the polyester resin (polyester resin segment).

(Method for producing crystalline polyester resin C)
Resin C can be produced, for example, by polycondensing raw material monomers containing an alcohol component and a carboxylic acid component.

The polycondensation of the alcohol component and the carboxylic acid component can be carried out, for example, in an inert gas atmosphere, in the presence of an esterification catalyst, an esterification promoter, a polymerization inhibitor, etc., as necessary, at a temperature of about 120° C. or higher and 250° C. or lower.
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).
The amount of the esterification catalyst used is preferably 0.01 parts by mass or more and 10 parts by mass or less relative to 100 parts by mass in total of the alcohol component and the carboxylic acid component which are raw material monomers for the resin C.
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 0.01 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.

(Physical Properties of Crystalline Polyester Resin C)
The softening point of Resin C is preferably 60° C. or higher, more preferably 65° C. or higher, and even more preferably 70° C. or higher, and from the viewpoint of further improving low-temperature fixability, it is preferably 150° C. or lower, more preferably 120° C. or lower, and even more preferably 100° C. or lower.
The melting point of resin C is preferably 50° C. or higher, more preferably 60° C. or higher, and even more preferably 70° C. or higher, and from the viewpoint of further improving low-temperature fixability, it is preferably 100° C. or lower, more preferably 95° C. or lower, and even more preferably 90° C. or lower.

The acid value of resin C is preferably 2 mgKOH/g or more, more preferably 4 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.

The solubility parameter (SP _C ) of resin C is preferably 8.70 (cal/cm ³ ) ^1/2 or more, more preferably 9.00 (cal/cm ³ ) ^1/2 or more, even more preferably 9.50 (cal/cm ³ ) ^1/2 or more, and preferably 11.00 (cal/cm ³ ) ^1/2 or less, more preferably 10.50 (cal/cm ³ ) ^1/2 or less, even more preferably 10.20 (cal/cm ³ ) ^1/2 or less. SP _C is a value calculated by the Fedors method.

The ester group concentration, softening point, melting point, acid value and solubility parameter of resin C can be adjusted as appropriate by the type and amount of raw material monomer used, as well as production conditions such as reaction temperature, reaction time and cooling rate, and the softening point, melting point and acid value 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 ester group concentration, softening point, melting point, acid value and solubility parameter values obtained as a mixture of these are each within the above-mentioned ranges.

In the toner particles, the mass ratio of the content of an amorphous polyester resin (resin A) described below to the content of resin C [resin A/resin C] is, from the viewpoint of the low-temperature fixability of the toner and the robustness of the printed coating film, preferably 55/45 or more, more preferably 60/40 or more, even more preferably 65/35 or more, and is preferably 90/10 or less, more preferably 85/15 or less, even more preferably 78/22 or less.
The content of crystalline polyester resin C in the toner 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, even more preferably 30% by mass or less.

<Amorphous polyester resin A>
The toner of the present invention contains an amorphous polyester resin A. Resin A is used as a binder resin for the toner, and is, for example, an amorphous polyester resin containing a polycondensate of an alcohol component and a carboxylic acid component.
Examples of the resin A include polyester resins and modified polyester resins. Examples of the modified polyester resins include urethane modified polyester resins, epoxy modified polyester resins, and composite resins containing polyester resin segments and addition polymerization resin segments. Among these, the resin A is preferably a polyester resin or a composite resin, and more preferably a composite resin.

Examples of the alcohol component of the resin A include alkylene oxide adducts of aromatic diols, linear or branched aliphatic diols, alicyclic diols, and trivalent or higher polyhydric alcohols. Among these, from the viewpoint of obtaining a toner having excellent low-temperature fixing properties, alkylene oxide adducts of aromatic diols and linear or branched aliphatic diols are preferred, and from the viewpoint of fastness of the printed coating film, alkylene oxide adducts of aromatic diols are more preferred.
The alkylene oxide adduct of an aromatic diol is preferably an alkylene oxide adduct of bisphenol A, more preferably represented by formula (I):

(wherein OR ¹ and R ² O are oxyalkylene groups, R ¹ and R ² each independently represent an ethylene group or a propylene group, x and y each 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).

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 at least a propylene oxide adduct of bisphenol A.
When an alkylene oxide adduct of bisphenol A is contained, the amount thereof in the alcohol component is preferably 80 mol % or more, more preferably 90 mol % or more, and 100 mol % or less, and even more preferably 100 mol %.

Examples of linear or branched aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, neopentyl glycol (2,2-dimethyl-1,3-propanediol), 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol.
When a linear or branched aliphatic diol is used as the alcohol component, the amount thereof in the alcohol component is preferably 80 mol % or more, more preferably 90 mol % or more, and 100 mol % or less, and even more preferably 100 mol %.
In the linear or branched aliphatic diol, the amount of neopentyl glycol is preferably 65 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%.

Examples of the alicyclic diol 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.

Examples of the carboxylic acid component of the resin A include dicarboxylic acids and polycarboxylic acids having three or more carboxylic acids.
Examples of the dicarboxylic acid include aromatic dicarboxylic acids, linear or branched aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Among these, at least one selected from aromatic dicarboxylic acids and linear or branched aliphatic dicarboxylic acids is preferred.
Examples of aromatic dicarboxylic acids include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid and terephthalic acid are preferred, and terephthalic acid is more preferred.
The amount of aromatic dicarboxylic acid in the carboxylic acid component is preferably 20 mol% or more, more preferably 30 mol% or more, even more preferably 40 mol% or more, and is 100 mol% or less, preferably 85 mol% or less, more preferably 80 mol% or less, even more preferably 75 mol% or less.

The linear or branched aliphatic dicarboxylic acid preferably has 2 or more carbon atoms, more preferably 3 or more carbon atoms, and preferably has 30 or less, more preferably 20 or less carbon atoms.
Examples of linear or branched aliphatic dicarboxylic acids include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, 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 or its anhydride, and octenylsuccinic acid. Among these, fumaric acid, sebacic acid, adipic acid, and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms are preferred.
When a linear or branched aliphatic dicarboxylic acid is contained, the amount thereof in the carboxylic acid component is preferably 5 mol % or more, more preferably 10 mol % or more, even more preferably 15 mol % or more, and is preferably 50 mol % or less, more preferably 45 mol % or less, even more preferably 40 mol % or less.
An example of the alicyclic dicarboxylic acid is cyclohexanedicarboxylic acid.

The trivalent or higher polyvalent carboxylic acid is preferably a trivalent carboxylic acid, such as trimellitic acid or 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.

When the resin A is a composite resin, an example of the addition polymerized resin segment is an addition polymer of raw material monomers containing a styrene-based compound.
Examples of the styrene-based compound include unsubstituted or substituted styrene. Examples of the substituent substituted on the styrene include an alkyl group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group having 1 to 5 carbon atoms, a sulfonic acid group, or a salt thereof.
Examples of styrene-based compounds include styrene, methylstyrene, α-methylstyrene, β-methylstyrene, tert-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid, and salts thereof. Among these, styrene is preferred.
In the raw material monomers for the addition polymerization resin segment, the content of the styrene-based compound is preferably 50% by mass or more, more preferably 65% by mass or more, even more preferably 75% by mass or more, and is 100% by mass or less, preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 85% by mass or less.

Examples of raw material monomers other than styrene-based compounds include (meth)acrylic acid esters such as alkyl (meth)acrylate, benzyl (meth)acrylate, and dimethylaminoethyl (meth)acrylate; olefins such as ethylene, propylene, and butadiene; halovinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether; vinylidene halides such as vinylidene chloride; and N-vinyl compounds such as N-vinylpyrrolidone. Among these, (meth)acrylic acid esters are preferred, and alkyl (meth)acrylates are more preferred.
The number of carbon atoms in the alkyl group in the alkyl (meth)acrylate is preferably 1 or more, more preferably 4 or more, even more preferably 6 or more, and is preferably 24 or less, more preferably 22 or less, even more preferably 20 or less.
Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, (iso)propyl (meth)acrylate, (iso or tertiary)butyl (meth)acrylate, (iso)amyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (iso)octyl (meth)acrylate, (iso)decyl (meth)acrylate, (iso)dodecyl (meth)acrylate, (iso)palmityl (meth)acrylate, (iso)stearyl (meth)acrylate, and (iso)behenyl (meth)acrylate. Of these, 2-ethylhexyl (meth)acrylate or stearyl (meth)acrylate is preferred, stearyl (meth)acrylate is more preferred, and stearyl methacrylate is even more preferred.

When the addition polymerization resin segment contains a constituent unit derived from a (meth)acrylic acid ester, the content of the (meth)acrylic acid ester in the raw material monomer of the addition polymerization resin segment is preferably 5 mass% or more, more preferably 10 mass% or more, even more preferably 15 mass% or more, and preferably 50 mass% or less, more preferably 35 mass% or less, even more preferably 25 mass% or less.

The total amount of styrene-based compounds and (meth)acrylic acid esters in the raw material monomers of the addition polymerization resin segment is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and even more preferably 100% by mass.

The composite resin preferably has a constitutional unit derived from a bireactive monomer bonded via a covalent bond to a polyester resin segment and an addition polymerization resin segment.
The term "structural unit derived from a bireactive monomer" refers to a unit formed by reaction of a functional group and an addition polymerizable group of a bireactive monomer.
An example of the addition polymerizable group is a carbon-carbon unsaturated bond (ethylenically unsaturated 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.
When the dual-reactive monomer is an addition-polymerizable monomer having a carboxy group, the amount of the constitutional unit derived from the dual-reactive monomer is preferably 1 part by mol or more, more preferably 5 parts by mol or more, even more preferably 8 parts by mol or more, and preferably 30 parts by mol or less, more preferably 25 parts by mol or less, even more preferably 20 parts by mol or less, relative to 100 parts by mol of the alcohol component of the polyester resin segment of the composite resin.

The content of the polyester resin segment in the composite resin is preferably 40% by mass or more, more preferably 45% by mass or more, even more preferably 55% by mass or more, and preferably 95% by mass or less, more preferably 90% by mass or less, 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 constituent unit derived from the bireactive monomer is a polyester resin segment.

The content of the addition polymerization resin segment in the composite resin is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, based on the total amount of the polyester resin segment and the addition polymerization resin segment, and is preferably 60% by mass or less, more preferably 55% by mass or less, even more preferably 45% by mass or less.

The amount of bireactive monomer-derived structural units in the composite resin is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 0.8% by mass or more, based on the total amount of the polyester resin segment and the addition polymerization resin segment, and is preferably 10% by mass or less, more preferably 7% by mass or less, even more preferably 4% by mass or less.

The total amount of polyester resin segments and addition polymerization resin segments in the composite resin 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.

The above amounts are calculated based on the ratio of the amounts of the polyester resin segment, raw material monomer for the addition polymerization resin segment, bireactive monomer, and 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 included in the addition polymerization resin segment in the calculation.

(Method for producing amorphous polyester resin A)
<Method for producing amorphous polyester resin>
When the resin A is an amorphous polyester resin, the resin A may be produced, for example, in the same manner as the resin C described above, by polycondensing raw material monomers containing an alcohol component and a carboxylic acid component.

<Method for producing composite resin>
When resin A is a composite resin containing a polyester resin segment and an addition polymerization resin segment, it 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 A may be carried out after step B, or step A and step B may be carried out simultaneously.
In step A, a part of the carboxylic acid component is subjected to a polycondensation reaction, and then step B is carried out, and thereafter the remainder of the carboxylic acid component is added to the polymerization system to further proceed with the polycondensation reaction of step A and the polycondensation reaction with, for example, a carboxy group possessed by the bireactive monomer or the constituent unit derived from the bireactive monomer.

In the step A, if necessary, the esterification catalyst and the esterification promoter described in the above-mentioned method for producing the crystalline polyester resin C may be used in the same amounts to carry out polycondensation.
When a monomer having an unsaturated bond such as fumaric acid is used in the polycondensation, the polymerization inhibitor described in the above-mentioned method for producing crystalline polyester resin C may be used in the same amount as above, if necessary.
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, and more preferably 240° C. or lower. The polycondensation may be carried out in an inert gas atmosphere.

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.

(Physical Properties of Amorphous Polyester Resin A)
The softening point of resin A is preferably 70° C. or higher, more preferably 90° C. or higher, and even more preferably 100° C. or higher, and is preferably 140° C. or lower, more preferably 130° C. or lower, and even more preferably 125° C. or lower.
The glass transition temperature of resin A is preferably 30° C. or higher, more preferably 35° C. or higher, and even more preferably 40° C. or higher, and is preferably 80° C. or lower, more preferably 75° C. or lower, and even more preferably 70° C. or lower.

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 35 mgKOH/g or less, even more preferably 30 mgKOH/g or less.

From the viewpoint of compatibility between resin C and resin A and recrystallization of resin C, the difference between SP _A and SP _C (SP _A - SP _C ) is preferably 0.50 (cal/cm ³ ) ^1/2 or more, more preferably 0.55 (cal/cm ³ ) ^1/2 or more, even more preferably 0.60 (cal/cm ³ ) ^1/2 or more, even more preferably 0.63 (cal/cm ³ ) ^1/2 or more, and is preferably 1.50 (cal/cm ³ ) ^1/2 or less, more preferably 1.30 (cal/cm ³ ) ^1/2 or less, even more preferably 1.00 (cal/cm ³ ) ^1/2 or less, even more preferably 0.95 (cal/cm ³ ) ^1/2 or less, and even more preferably 0.90 (cal/cm ³ ) ^1/2 or less.

From the viewpoint of controlling "SP _A - SP _C " within the above range, the solubility parameter (SP _A ) of resin A is preferably 9.20 (cal/cm ³ ) ^1/2 or more, more preferably 9.50 (cal/cm ³ ) ^1/2 or more, even more preferably 10.00 (cal/cm ³ ) ^1/2 or more, and preferably 12.00 (cal/cm ³ ) ^1/2 or less, more preferably 11.80 (cal/cm ³ ) ^1/2 or less, even more preferably 11.50 (cal/cm ³ ) ^1/2 or less. SP _A is a value calculated by the Fedors method.

The softening point, glass transition temperature, acid value and solubility parameter 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, it is preferable that the softening point, glass transition temperature, acid value and solubility parameter of the resulting mixture are each within the above-mentioned ranges.
The content of the amorphous polyester resin A in the toner particles is preferably 50% by mass or more, more preferably 55% by mass or more, even more preferably 60% by mass or more, and is preferably 87% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less.

<Coloring Agent>
In the present invention, the toner particles contain a pigment as a colorant.
When the total number of -NH- and _-NH2 groups in one molecule of the pigment is divided by the molecular weight of the pigment to define the NH group amount, the NH group amount of the pigment is 6.0 mmol/g or more. There is no particular upper limit, but it is preferably 20.0 mmol/g or less, and more preferably 15.0 mmol/g or less.
The colorant used in the present invention is preferably a yellow organic pigment, and from the viewpoint of achieving a desired NH group amount, is preferably at least one of an isoindoline pigment and a benzimidazolone pigment.
Examples of isoindoline pigments include C.I. Pigment Yellow 139 (total number of -NH- and _-NH2 in one molecule = 5, molecular weight = 367, NH group amount = 13.6 mmol / g), and C.I. Pigment Yellow 185 (total number of -NH- and _-NH2 in one molecule = 4, molecular weight = 337, NH group amount = 11.9 mmol / g).
An example of the benzimidazolone pigment is C.I. Pigment Yellow 180 (total number of -NH- and _-NH2 in one molecule = 6, molecular weight = 733, NH group amount = 8.2 mmol/g).
The pigment used in the present invention is preferably at least one selected from C. I. Pigment Yellow 185 and C. I. Pigment Yellow 180 from the viewpoint of obtaining a printed coating film having high fastness.

From the viewpoint of improving dispersibility in the toner particles, the amount of colorant is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, and even more preferably 7 parts by mass or more, relative to 100 parts by mass of the total of Resin C and Resin A, and is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 15 parts by mass or less.
The content of the colorant in the toner particles is preferably 3% by mass or more, more preferably 5% by mass or more, and preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less.

<Release Agent>
The toner particles of the present invention preferably contain a release agent.
Examples of the release agent include polypropylene wax, polyethylene wax, ethylene propylene copolymer wax, hydrocarbon wax such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax, or oxides thereof, ester wax such as carnauba wax, montan wax, or deacidified wax thereof, or fatty acid ester wax, fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts. These may be used alone or in combination of two or more.

The melting point of the release agent is preferably 60° C. or higher, more preferably 70° C. or higher, and preferably 160° C. or lower, more preferably 140° C. or lower, even more preferably 120° C. or lower, and even more preferably 100° C. or lower.
The content of the release agent in the toner particles is preferably 0.1% by mass or more, more preferably 1% by mass or more, even more preferably 3% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less.
In addition, the toner particles may contain additives such as a charge control agent, a magnetic powder, a flowability improver, a conductivity adjuster, a reinforcing filler such as a fibrous substance, an antioxidant, an antiaging agent, and a cleaning property improver.

(Physical Properties of Toner Particles)
The volume median particle diameter _D50 of the toner particles is, from the viewpoint of obtaining a printed coating film with good image quality and from the viewpoint of further improving the cleaning property of the toner, 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.

From the viewpoint of obtaining a printed coating (image) of good quality, the circularity of the toner particles is preferably 0.950 or more, more preferably 0.955 or more, and even more preferably 0.960 or more, and from the viewpoint of cleaning properties, it is preferably 0.990 or less, more preferably 0.985 or less, and even more preferably 0.980 or less.

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 a printed coating film with high robustness.
The volume median particle diameter D ₅₀ , circularity and CV value of the toner particles can be measured by the method described in the examples.

[Toner manufacturing method]
The toner according to an embodiment of the present invention may be produced by any of the known methods such as a melt kneading method, an emulsion phase inversion method, a suspension polymerization method, and an emulsion aggregation method, but the emulsion aggregation method is preferred.

<Emulsion aggregation method>
The emulsion aggregation method includes a step of aggregating and fusing resin particles, which contain resin C and resin A in the same or different particles, and a colorant in an aqueous medium.

(Step of aggregating resin particles)
In the step of aggregating the resin particles, the resin particles containing the resin C and the resin A in the same or different particles and the colorant are aggregated in an aqueous medium to obtain aggregated particles 1. It is preferable to mix a resin particle dispersion containing the resin particles with a colorant particle dispersion containing a colorant to aggregate these particles and obtain aggregated particles 1. Here, it is preferable to further aggregate the release agent in addition to the resin particles and the colorant, and it is more preferable to mix a resin particle dispersion containing the resin particles, a colorant particle dispersion containing a colorant, and a release agent particle dispersion containing a release agent to aggregate these particles to obtain aggregated particles 1. It is more preferable that the resin particle dispersion, the colorant particle dispersion, and the release agent particle dispersion are respectively an aqueous dispersion of resin particles, an aqueous dispersion of colorant particles, and an aqueous dispersion of release agent particles.

In the present invention, the aqueous medium used in the aqueous dispersion is a medium containing water as a main component, and the content of water in the aqueous medium is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, and 100% by mass or less. As the water, deionized water or distilled water is preferable.
Examples of components other than water that can constitute the 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. Among these, alkyl alcohols having 1 to 5 carbon atoms are preferred, and ethanol is more preferred.

<Method for producing resin particle dispersion>
The resin particles of resin C and the resin particles of resin A may be prepared as an aqueous dispersion of resin particles containing resin C and resin A in the same or different particles.

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 of adding an aqueous medium to an organic solvent solution of resin C and/or resin A or molten resin C and/or resin A to perform phase inversion emulsification. A method of adding an aqueous medium to an organic solvent solution of resin C and/or resin A 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 C and the resin A 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 resin C and/or resin A contained in the resin particles is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 30 mol% or more, even more preferably 40 mol% or more, and is 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 C and/or the resin A contained in the resin particles can be calculated by the following formula.
Degree of neutralization (mol %)=[{weight of neutralizing agent added (g)/equivalent of neutralizing agent}/[{weighted average acid value of resin constituting resin particle (mg KOH/g)×weight of resin constituting resin particle (g)}/(56×1000)]]×100

While stirring the organic solvent solution or the molten resin C and/or resin A, the aqueous medium is gradually added to cause phase inversion.
From the viewpoint of improving the dispersion stability of the resin particles containing resin C and/or resin A, 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.

After phase inversion emulsification, the organic solvent may be removed from the obtained dispersion by distillation or the like, if necessary. The resin particles may also be isolated by filtration or the like. It is preferable to use an aqueous dispersion of resin particles from which the organic solvent has been removed from the dispersion obtained after phase inversion emulsification. In this case, the remaining amount of organic solvent in the dispersion is preferably 1 mass % or less, more preferably 0.5 mass % or less, and even more preferably substantially 0 mass %.

The volume median particle size _D50 of the resin particles in the dispersion is preferably 0.05 μm or more, more preferably 0.08 μm or more, and preferably 1 μm or less, more preferably 0.5 μm or less, and further preferably 0.3 μm or less.
The CV value of the resin particles in the dispersion is preferably 10% or more, more preferably 20% or more, and is preferably 40% or less, more preferably 35% or less.
The volume median particle diameter _D50 and CV value of the resin particles in the dispersion are measured by the method described in the examples.

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 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less.
The solid content is the total amount of non-volatile components.
In the process of aggregating the resin particles, the aggregated particles 1 may contain a release agent, and may also contain other additives such as a charge control agent, a magnetic powder, a flowability improver, a conductivity adjuster, a reinforcing filler such as a fibrous substance, an antioxidant, an anti-aging agent, and a cleaning property improver.

<<Method for producing colorant particle dispersion>>
The colorant particle dispersion is preferably obtained by dispersing the pigment and an aqueous medium using a dispersing machine such as a homomixer, a homogenizer, an ultrasonic dispersing machine, etc. The dispersion is preferably carried out in the presence of a surfactant from the viewpoint of improving the dispersion stability of the pigment.
In addition, from the viewpoint of improving the dispersion stability of the pigment, the pigment may be dispersed in the presence of the addition polymer E. The addition polymer E preferably has a structural 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, the addition polymer E described in JP-A-2021-026129 is referred to.

Surfactants that improve the dispersion stability of the pigment include, for example, nonionic surfactants, anionic surfactants, and cationic surfactants, and from the viewpoint of improving the dispersion stability of the pigment, nonionic surfactants are preferred. Examples of nonionic surfactants include polyoxyalkylene alkyl ethers, polyoxyalkylene alkenyl ethers, and polyoxyalkylene aryl ethers. Among these, polyoxyethylene aryl ethers are preferred, and polyoxyethylene distyrenated phenyl ether is more preferred.

The content of the surfactant in the colorant particle dispersion is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more, per 100 parts by mass of pigment, from the viewpoint of improving the dispersion stability of the pigment, and is preferably 50 parts by mass or less, more preferably 45 parts by mass or less, and even more preferably 40 parts by mass or less.

In the colorant particle dispersion, the pigment is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 30% by mass or less.
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 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less.

From the viewpoint of improving dispersibility in toner particles, the colorant particles have a volume median particle size _D50 of preferably 0.05 μm or more, more preferably 0.08 μm or more, even more preferably 0.1 μm or more, and preferably 0.4 μm or less, more preferably 0.3 μm or less, even more preferably 0.2 μm or less.
From the viewpoint of improving dispersibility in the toner particles, the CV value of the colorant particles is preferably 10% or more, more preferably 20% or more, and is preferably 45% or less, more preferably 40% or less, and even more preferably 35% or less.
The volume median particle diameter _D50 and CV value of the colorant particles are measured by the methods described in the Examples.

(Method for producing release agent particle dispersion)
The release agent particle dispersion liquid can be obtained, for example, by dispersing a release agent, a dispersion liquid of resin particles S described below, and, if necessary, an aqueous medium at a temperature equal to or higher than the melting point of the release agent, using a dispersing machine such as a homogenizer, a high-pressure dispersing machine, or an ultrasonic dispersing machine.
The heating temperature during dispersion is preferably equal to or higher than the melting point of the release agent and equal to or higher than 80°C, more preferably equal to or higher than 85°C, even more preferably equal to or higher than 90°C, and is preferably equal to or lower than 100°C, more preferably equal to or lower than 98°C, even more preferably equal to or lower than 96°C.

The release agent particle dispersion can be obtained by using a surfactant, but is preferably obtained by mixing the release agent with resin particles S, which will be described later. By preparing the release agent particles using the release agent and resin particles S, the release agent particles are stabilized by the resin particles S, 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 S are attached to the surfaces of the release agent particles.

The resin constituting the resin particles S 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 details of the composite resin D, see, for example, JP 2021-026129 A.

From the viewpoint of affinity with resin A, the solubility parameter (SP _D ) of composite resin D may be approximately the same as that of SP _A.

The volume median particle diameter _D50 of the release agent particles in the release agent particle dispersion is, from the viewpoint of obtaining uniform aggregated particles by aggregation, preferably 0.05 μm or more, more preferably 0.2 μm or more, even more preferably 0.4 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 in the release agent particle dispersion is preferably 10% or more, more preferably 20% or more, and is preferably 40% or less, more preferably 35% or less, and further preferably 30% or less.
The volume median particle diameter _D50 and CV value of the release agent particles in the release agent particle dispersion liquid are measured by the method described in the Examples.

-Surfactants-
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 performed 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 parts by mass or more, more preferably 0.3 parts by mass or more, and even more preferably 0.5 parts by mass or more, per 100 parts by mass of the combined amount of Resin C and Resin A, and is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less.

- 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 aggregated 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.

For example, 5 to 50 parts by mass of the aggregating agent is added to a mixed dispersion liquid containing resin particles, release agent particles, and colorant particles at 0°C to 40°C, per 100 parts by mass of resin in the resin particles, 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.

Methods for stopping aggregation include cooling the dispersion, adding an aggregation stopper, diluting the dispersion, etc. From the viewpoint of reliably preventing unnecessary aggregation, the method of stopping aggregation by adding an aggregation stopper is preferred.

- Aggregation stopper -
The aggregation terminator is preferably a surfactant, more preferably an anionic surfactant.The anionic surfactant may be, for example, an alkylbenzenesulfonate, an alkyl sulfate, an alkyl ether sulfate, a polyoxyalkylene alkyl ether sulfate, an arylsulfonate, an arylsulfonic acid formalin condensate, etc., and is preferably an alkali metal salt of an arylsulfonic acid formalin condensate, more preferably a sodium salt of a 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 5 parts by mass or more, per 100 parts by mass of the total of Resin C and Resin A, from the viewpoint of reliably preventing unnecessary aggregation, and is preferably 60 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less, from the viewpoint of reducing residue in the toner.

The volume median particle diameter D ₅₀ of the aggregated particles 1 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.

In the present invention, after the step of aggregating the resin particles and before the step of fusing, a step of adhering shell resin particles containing an amorphous resin (preferably amorphous polyester-based resin B) to the obtained aggregated particles 1 and aggregating them to obtain aggregated particles 2 may be included. 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 polyester resin B used in the shell resin particles include the above-mentioned resin A. The shell resin particles can be obtained by the same method as the method for producing the resin particles containing the above-mentioned resin C and/or resin A.
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 as toner particles, and a method of stopping the aggregation by adding the above-mentioned aggregation terminator is preferable.
From the viewpoint of low-temperature fixing property of the toner, the mass ratio of the shell resin particles to the mass of the aggregated particles 1 [shell resin particles/aggregated particles 1] is preferably 1/99 or more, more preferably 3/97 or more, even more preferably 5/95 or more, and is preferably 25/75 or less, more preferably 20/80 or less, even more preferably 15/85 or less.

(Fusing process)
In the fusion step, for example, the aggregated particles 1 or the aggregated particles 2 are fused in an aqueous medium.
By fusion, the particles contained in aggregated particles 1 or aggregated particles 2 are fused together to obtain fused particles.
In the fusion step, from the viewpoint of improving the fusion properties of the aggregated particles 1 or 2 and from the viewpoint of improving the low-temperature fixing properties of the toner, 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 amorphous polyester-based resins contained in the aggregated particles.
The holding temperature when fusing the aggregated particles, from the viewpoint of improving the fusing property of the aggregated particles and improving the productivity of the toner, is preferably at least 2° C. higher, more preferably at least 3° C. higher, and even more preferably at least 5° C. higher than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous polyester resins, and is preferably not higher than 30° C. higher, more preferably not higher than 25° C. higher, and even more preferably not higher than 20° C. higher than the glass transition temperature of the resin having the highest glass transition temperature among the amorphous polyester resins.
In this case, the time for which the toner is maintained at a temperature equal to or higher than the glass transition temperature of the amorphous polyester resin is, from the viewpoint of improving the low-temperature fixing property of the toner, preferably 1 minute or more, more preferably 10 minutes or more, even more preferably 30 minutes or more, and is preferably 240 minutes or less, more preferably 180 minutes or less, even more preferably 120 minutes or less, even more preferably 90 minutes or less.
It is preferable to maintain the temperature at the above temperature until the desired circularity is achieved.

The volume median particle size _D50 of the fused particles obtained by fusion is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and is preferably 10 μm or less, more preferably 8 μm or less, even more preferably 7 μm or less.

The circularity of the fused particles obtained by fusion is preferably 0.955 or more, more preferably 0.960 or more, and 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.

(Post-processing process)
A post-treatment process may be performed after the fusion process, and the fused particles are isolated to obtain toner particles. Since the fused particles obtained in the fusion process are present in an aqueous medium, it is preferable to first perform solid-liquid separation. For 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.

<Melt kneading method>
In the present invention, the melt-kneading method involves, for example, uniformly mixing a binder resin, a colorant, and, if necessary, additives such as a release agent in a mixer such as a Henschel mixer, and then melt-kneading the mixture in an internal kneader, a single-screw or twin-screw extruder, an open roll type kneader, etc. The mixture is then cooled, pulverized, and classified to produce toner particles.

The toner contains toner particles. The obtained toner particles can be used as is as the toner of the present invention. It is also preferable to use toner particles that have been treated by adding an external additive to the surface thereof as the toner of the present invention.

<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 surface treatment of the toner particles is performed 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, even more preferably 3 parts by mass or more, and is 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.

Toner is used to develop electrostatic images in electrophotographic printing. Toner can be used, for example, as a one-component developer or mixed with a carrier to form a two-component developer.

In combination with the above embodiment, the present invention discloses the following embodiments.
<1>
A toner for developing electrostatic images, comprising a crystalline polyester resin C, an amorphous polyester resin A, and a colorant,
the crystalline polyester resin C contains a structural unit derived from an aliphatic diol component containing ethylene glycol and a structural unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, and has an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g,
The colorant is a pigment having an NH group amount of 6.0 mmol/g or more when the total number of -NH- and _-NH2 groups in one molecule is divided by the molecular weight to define the NH group amount.
Toner for developing electrostatic images.
＜2＞
The toner for developing an electrostatic image according to <1>, wherein the crystalline polyester resin C further contains a structural unit derived from a monocarboxylic acid component having 6 to 24 carbon atoms.
＜3＞
The toner for developing electrostatic images according to <2>, wherein the number of carbon atoms in the constitutional unit derived from the monocarboxylic acid component having from 6 to 24 carbon atoms is preferably 8 or more, more preferably 12 or more, even more preferably 14 or more, still more preferably 16 or more, and is preferably 22 or less, more preferably 20 or less.
＜4＞
The toner for developing electrostatic images according to <2> or <3>, wherein the content of the structural units derived from a monocarboxylic acid component having from 6 to 24 carbon atoms is 1 mol % or more, preferably 5 mol % or more, more preferably 7 mol % or more, and 35 mol % or less, preferably 30 mol % or less, more preferably 20 mol % or less, and even more preferably 15 mol % or less, in the structural units derived from a carboxylic acid component of the crystalline polyester resin C.
＜5＞
The toner for developing electrostatic images according to any one of <1> to <4>, wherein the constitutional unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms includes a constitutional unit derived from an α,ω-linear aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms.
＜6＞
The toner for developing electrostatic images according to any one of <1> to <5>, wherein the structural unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms includes at least one selected from a structural unit derived from sebacic acid, a structural unit derived from 1,11-undecanedioic acid, a structural unit derived from 1,12-dodecanedioic acid, a structural unit derived from 1,13-tridecanedioic acid, and a structural unit derived from 1,14-tetradecanedioic acid, preferably at least one selected from a structural unit derived from sebacic acid, a structural unit derived from 1,12-dodecanedioic acid, and a structural unit derived from 1,14-tetradecanedioic acid, more preferably a structural unit derived from 1,12-dodecanedioic acid and/or a structural unit derived from 1,14-tetradecanedioic acid.
＜７＞
The toner for developing electrostatic images according to any one of <1> to <6>, wherein the content of the constitutional units derived from the aliphatic diol component in the constitutional units derived from the alcohol component of the crystalline polyester resin C is 80 mol % or more, preferably 85 mol % or more, more preferably 90 mol % or more, and even more preferably 95 mol % or more, and 100 mol % or less.
＜8＞
The toner for developing electrostatic images according to any one of <1> to <7>, wherein the content of the constitutional units derived from ethylene glycol in the constitutional units derived from an alcohol component of the crystalline polyester resin C is 65 mol % or more, preferably 85 mol % or more, more preferably 90 mol % or more, and still more preferably 95 mol % or more and 100 mol % or less.
＜9＞
The toner for developing electrostatic images according to any one of <1> to <8>, wherein the content of the constitutional units derived from an aliphatic dicarboxylic acid having from 10 to 14 carbon atoms is 70 mol % or more, preferably 75 mol % or more, more preferably 80 mol % or more, and even more preferably 85 mol % or more, and 100 mol % or less, in the constitutional units derived from a carboxylic acid component of the crystalline polyester resin C.
＜10＞
The toner for developing electrostatic images according to any one of <1> to <9>, wherein the ester group concentration of the crystalline polyester resin C is 6.7 mmol/g or more and 8.8 mmol/g or less, and preferably 8.6 mmol/g or less.
<11>
The toner for developing electrostatic images according to any one of <1> to <10>, wherein the softening point of the crystalline polyester resin C is 60° C. or higher, preferably 65° C. or higher, more preferably 70° C. or higher, and 150° C. or lower, preferably 120° C. or lower, more preferably 100° C. or lower.
＜12＞
The toner for developing electrostatic images according to any one of <1> to <11>, wherein the melting point of the crystalline polyester resin C is 50° C. or higher, preferably 60° C. or higher, more preferably 70° C. or higher, and 100° C. or lower, preferably 95° C. or lower, more preferably 90° C. or lower.
＜13＞
The toner for developing electrostatic images according to any ^one of <1> to <12>, wherein the solubility parameter of the crystalline polyester resin C is 8.70 (cal/cm ³ ) ^1/2 or more, preferably 9.00 (cal/cm ³ ) ^1/2 or more, more preferably 9.50 (cal/cm ³ ) ^1/2 or more, and 11.00 (cal/cm ³ ) ^1/2 ^or less, preferably 10.50 (cal/cm ³ ) 1/2 or less, more preferably 10.20 (cal/cm 3 ) ^1/2 or less.
＜14＞
The toner for developing electrostatic images according to any one of <1> to <13>, wherein the structural unit derived from an alcohol component of the amorphous polyester resin A is at least one selected from the group consisting of a structural unit derived from an alkylene oxide adduct of an aromatic diol, a structural unit derived from a linear or branched aliphatic diol, a structural unit derived from an alicyclic diol, and a structural unit derived from a trivalent or higher polyhydric alcohol, and preferably includes a structural unit derived from an alkylene oxide adduct of an aromatic diol and/or a structural unit derived from a linear or branched aliphatic diol.
＜15＞
The toner for developing electrostatic images according to any one of <1> to <14>, wherein the structural unit derived from an alcohol component of the amorphous polyester resin A includes a structural unit derived from an alkylene oxide adduct of an aromatic diol, preferably a structural unit derived from an alkylene oxide adduct of bisphenol A, more preferably a structural unit derived from an alkylene oxide adduct of 2,2-bis(4-hydroxyphenyl)propane represented by the following formula (I), even more preferably a structural unit derived from a propylene oxide adduct of bisphenol A and/or a structural unit derived from an ethylene oxide adduct of bisphenol A, still more preferably a structural unit derived from a propylene oxide adduct of bisphenol A.

(In the formula, ^OR1 and ^R2O are oxyalkylene groups, ^R1 and ^R2 each independently represent an ethylene group or a propylene group, x and y each 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, more preferably 4 or less.)
＜16＞
The toner for developing electrostatic images according to <15>, wherein the content of the structural units derived from an alkylene oxide adduct of bisphenol A is 80 mol % or more, preferably 90 mol % or more and 100 mol % or less, in the structural units derived from an alcohol component of the amorphous polyester resin A.
＜１７＞
The toner for developing electrostatic images according to any one of <1> to <14>, wherein the structural unit derived from an alcohol component of the amorphous polyester resin A includes a structural unit derived from the linear or branched aliphatic diol.
＜18＞
The toner for developing electrostatic images according to <17>, wherein the structural units derived from the linear or branched aliphatic diol contain structural units derived from neopentyl glycol, and the content of the structural units derived from neopentyl glycol in the structural units derived from the linear or branched aliphatic diol is 65 mol % or more, preferably 85 mol % or more, more preferably 90 mol % or more, and even more preferably 95 mol % or more and 100 mol % or less.
＜19＞
The toner for developing electrostatic images according to any one of <1> to <18>, wherein the structural unit derived from a carboxylic acid component of the amorphous polyester resin A includes at least one selected from the group consisting of a structural unit derived from an aromatic dicarboxylic acid, a structural unit derived from a linear or branched aliphatic dicarboxylic acid, and a structural unit derived from an alicyclic dicarboxylic acid, and is preferably at least one selected from the group consisting of a structural unit derived from an aromatic dicarboxylic acid and a structural unit derived from a linear or branched aliphatic dicarboxylic acid.
＜20＞
The toner for developing electrostatic images according to any one of <1> to <19>, wherein the structural unit derived from an aromatic dicarboxylic acid includes at least one selected from the group consisting of a structural unit derived from phthalic acid, a structural unit derived from isophthalic acid, and a structural unit derived from terephthalic acid, preferably a structural unit derived from isophthalic acid and/or a structural unit derived from terephthalic acid, and more preferably a structural unit derived from terephthalic acid.
＜21＞
The toner for developing electrostatic images according to any one of <1> to <20>, wherein the softening point of the amorphous polyester resin A is 70° C. or higher, preferably 90° C. or higher, more preferably 100° C. or higher, and is 140° C. or lower, preferably 130° C. or lower, more preferably 125° C. or lower.
＜22＞
The toner for developing electrostatic images according to any one of <1> to <21>, wherein the glass transition temperature of the amorphous polyester resin A is 30° C. or higher, preferably 35° C. or higher, more preferably 40° C. or higher, and 80° C. or lower, preferably 75° C. or lower, more preferably 70° C. or lower.
＜23＞
The toner for developing electrostatic images according to any ^one of <1> to <22>, wherein the solubility parameter of the amorphous polyester resin A is 9.20 (cal/cm ³ ) ^1/2 or more, preferably 9.50 (cal/cm ³ ) ^1/2 or more, more preferably 10.00 (cal/cm ³ ) ^1/2 or more, and is 12.00 (cal/cm 3 ) ^1/2 or less, preferably 11.80 (cal/cm ³ ) ^1/2 or less, more preferably 11.50 (cal/cm ³ ) ^1/2 or less.
＜24＞
The toner for developing electrostatic images according to any one of <1> to <23>, wherein a difference in solubility parameter between the amorphous polyester resin A and the crystalline polyester resin C is 0.50 (cal/cm ³ ) ^1/2 or more, preferably 0.55 (cal/cm ³ ) ^1/2 or more, more preferably 0.60 (cal/cm ³ ) ^1/2 or more, even more ^{preferably 0.63 (cal/cm 3 ) 1/2 or more, and is 1.50 (cal/cm 3 ) 1/2 or less, preferably 1.30 (cal/cm 3} ⁾ ^1/2 ^or ^less ^, ^more ^preferably 1.00 (cal/cm 3 ) 1/2 or less, even more preferably 0.95 (cal/cm ³ ) ^1/2 or less, and even more preferably 0.90 (cal/cm ³ ) ^1/2 or less.
＜25＞
The toner for developing electrostatic images according to any one of <1> to <24>, wherein a mass ratio of a content of the amorphous polyester resin A to a content of the crystalline polyester resin C is 55/45 or more, preferably 60/40 or more, more preferably 65/35 or more, and is 90/10 or less, preferably 85/15 or less, more preferably 78/22 or less.
＜26＞
The toner for developing electrostatic images according to any one of <1> to _<25> , wherein the colorant is a pigment having an NH group amount of 6.0 mmol/g or more, and the NH group amount is 20.0 mmol/g or less, and preferably 15.0 mmol/g or less, when the NH group amount is the value obtained by dividing the total number of -NH- and -NH2 groups in one molecule by the molecular weight.
＜27＞
The toner for developing electrostatic images according to any one of <1> to <26>, wherein the colorant is a yellow organic pigment.
＜28＞
The toner for developing electrostatic images according to any one of <1> to <27>, wherein the colorant contains at least one pigment selected from the group consisting of isoindoline pigments and benzimidazolone pigments.
＜29＞
The toner for developing an electrostatic image according to any one of <1> to <28>, wherein the colorant is at least one selected from the group consisting of C. I. Pigment Yellow 185 and C. I. Pigment Yellow 180.
＜30＞
The toner for developing electrostatic images according to any one of <1> to <29>, wherein the content of the colorant is 3 parts by mass or more, preferably 5 parts by mass or more, and more preferably 7 parts by mass or more, and is 25 parts by mass or less, preferably 20 parts by mass or less, and more preferably 15 parts by mass or less, relative to 100 parts by mass in total of the crystalline polyester resin C and the amorphous polyester resin A.
＜31＞
The toner for developing electrostatic images according to any one of <1> to <30>, wherein the toner for developing electrostatic images contains toner particles, and a content of the colorant in the toner particles is 3% by mass or more, preferably 5% by mass or more, and 25% by mass or less, preferably 20% by mass or less, and more preferably 15% by mass or less.
＜32＞
The toner for developing electrostatic images according to any one of <1> to <31>, which has a core-shell structure.
＜33＞
A method for producing a toner for developing an electrostatic image, comprising a step of aggregating and fusing resin particles, the resin particles including a crystalline polyester resin C and an amorphous polyester resin A in the same or different particles, and a colorant in an aqueous medium, the method comprising the steps of:
the crystalline polyester resin C contains a structural unit derived from an aliphatic diol component containing ethylene glycol and a structural unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, and has an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g,
The colorant is a pigment having an NH group amount of 6.0 mmol/g or more when the total number of -NH- and _-NH2 groups in one molecule is divided by the molecular weight to define the NH group amount.
A method for producing a toner for developing electrostatic images.
＜34＞
The method for producing a toner for developing an electrostatic image according to <33>, further comprising a step of adhering shell resin particles containing an amorphous resin to aggregate particles 1 obtained in the aggregating step and aggregating the aggregated particles 2, after the aggregating step and before the fusion step.
＜35＞
The method for producing a toner for developing an electrostatic image according to <34>, wherein a mass ratio of the shell resin particles to the mass of the aggregated particles 1 [shell resin particles/aggregated particles 1] is 1/99 or more, preferably 3/97 or more, more preferably 5/95 or more, and is 25/75 or less, preferably 20/80 or less, more preferably 15/85 or less.

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples in any way.
In the notation "alkylene oxide (X)", the number X in parentheses means the average number of moles of alkylene oxide added.

[Measuring method]
The properties of the polyester resin, the resin particles, the toner, etc. were measured and evaluated by the following methods.
[Softening point, crystallinity index, melting point and glass transition temperature of resin]
(1) Softening point Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), 1 g of a sample was extruded from a nozzle having a diameter of 1 mm and a length of 1 mm under a load of 1.96 MPa applied by a plunger while heating the sample at a temperature increase rate of 6°C/min. 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 a sample was weighed into an aluminum pan and cooled to 0°C at a temperature drop rate of 10°C/min. The sample was then left to stand for 1 minute, and then heated to 180°C at a temperature increase rate of 10°C/min to measure the amount of heat. The temperature of the peak with the largest peak area among the observed endothermic peaks was defined 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 a sample was weighed into an aluminum pan, heated to 200°C, and cooled from that temperature 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. Among the endothermic peaks observed, the temperature of the peak with the largest peak area was taken as the maximum endothermic peak temperature (2). In the case of a crystalline resin, this 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 as the glass transition temperature. When no peak was observed but a step was observed, the temperature at the intersection of the tangent showing the maximum slope of the curve at the step and an extension of the baseline on the low temperature side of the step was taken as the glass transition temperature.

[Acid value of resin]
The acid value of the resin was measured in accordance with JIS K0070:1992, except that the measurement solvent was a mixed solvent of acetone and toluene (acetone:toluene=1:1 (volume ratio)).

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

[Volume Median Particle Size _D50 and CV Value of Resin Particles, Colorant Particles, and Release Agent Particles]
(1) Measuring device: Laser diffraction type particle size measuring instrument "LA-920" (manufactured by Horiba, Ltd.)
(2) Measurement conditions: A sample dispersion was placed in a measurement cell, distilled water was added, and the volume median particle size _D50 and the volume average particle size Dv were measured at a concentration where the absorbance was in the appropriate range. 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

[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 content (mass%)=100-moisture (mass%)

[Volume Median Particle Diameter _D50 of Agglomerated Particles]
・Measuring instrument: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.)
Aperture diameter: 50 μm
Analysis software: "Multisizer (registered trademark) III version 3.51" (Beckman Coulter, Inc.)
・Electrolyte: "Isoton (registered trademark) II" (Beckman Coulter, Inc.)
Measurement conditions: The sample dispersion was added to 100 mL of the electrolyte to adjust the concentration to a level where the particle sizes of 30,000 particles could be measured in 20 seconds, and then the 30,000 particles were measured again, and the volume median particle size _D50 was calculated from the particle size distribution.

[Circularity of fused particles]
・Measuring device: Flow type particle image analyzer "FPIA-3000" (manufactured by 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

[Volume Median Particle Size _D50 and CV Value of Toner Particles]
The measuring device, aperture diameter, analysis software, and electrolyte used were the same as those used in the measurement of the volume median particle diameter D ₅₀ of the agglomerated particles described above.
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 the mixture was dispersed for 1 minute using an ultrasonic disperser. Thereafter, 25 mL of the electrolyte solution 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 was added to 100 mL of the electrolyte to adjust the concentration to a level that would allow the particle sizes of 30,000 particles to be measured in 20 seconds. The 30,000 particles were then measured, and the volume median particle size _D50 and volume average particle size _DV were determined from the particle size distribution.
The CV value (%) was calculated according to the following formula:
CV value (%) = (standard deviation of particle size distribution / volume average particle size D _V ) × 100

[Circularity of Toner Particles]
・Measuring device: Flow type particle image analyzer "FPIA-3000" (manufactured by Sysmex Corporation)
Preparation of dispersion: A dispersion of toner particles was prepared by diluting with deionized water so that the solid content concentration was 0.001 to 0.05% by mass.
Measurement mode: HPF measurement mode

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

Production Example A2 (Production of Resin A-2)
Resin A-2 was obtained in the same manner as in Production Example A1, except that the amounts of raw material monomers for the polyester resin segment, etc. were changed as shown in Table 1. The physical properties are shown in Table 1.

Production Example A3 (Production of Resin A-3)
The raw material monomers of polyester resin other than isophthalic acid shown in Table 1, esterification catalyst, and esterification promoter were placed in a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube equipped with a fractionating tube through which hot water of 98 ° C. was passed, a stirrer, and a thermocouple. Under a nitrogen atmosphere, the reaction system was held at 180 ° C. for 1 hour, and then heated from 180 ° C. to 230 ° C. at 10 ° C. / h, and then held at 230 ° C. for 5 hours to perform polycondensation. After that, after cooling to 180 ° C., isophthalic acid was added to the reaction system, the temperature was raised from 180 ° C. to 230 ° C. at 10 ° C. / h, and the reaction was carried out at 230 ° C. for 1 hour, and the reaction was carried out at 230 ° C. and 10 kPa until the softening point shown in Table 1 was obtained. The physical properties are shown in Table 1.

[Production of amorphous polyester resin B]
Production Example B1 (Production of Resin B-1)
In a 20 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. Trimellitic anhydride was further added, and the mixture was reacted at 180°C until the softening point shown in Table 1 was reached, yielding Resin B-1. The physical properties are shown in Table 1.

Production Example B2 (Production of Resin B-2)
The raw material monomers of polyester resin other than fumaric acid shown in Table 1, esterification catalyst, and esterification promoter were placed in a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube equipped with a fractionating tube through which hot water of 98 ° C. was passed, a stirrer, and a thermocouple. Under a nitrogen atmosphere, the reaction system was held at 180 ° C. for 1 hour, and then heated from 180 ° C. to 230 ° C. at 10 ° C. / h, and then held at 230 ° C. for 5 hours to perform polycondensation. After that, after cooling to 180 ° C., 5 g of fumaric acid and radical polymerization inhibitor were added to the reaction system, the temperature was raised from 180 ° C. to 210 ° C. at 10 ° C. / h, and the reaction was carried out at 210 ° C. for 1 hour, and the reaction was carried out at 210 ° C. and 10 kPa until the softening point shown in Table 1 was obtained. The physical properties are shown in Table 1.

[Production of Composite Resin D]
Production Example D1 (Production of Resin D-1)
The inside of a 10 L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3450 g of a propylene oxide (2.2) adduct of bisphenol A, 655 g of terephthalic acid, 24 g of tin (II) di(2-ethylhexanoate), and 2.4 g of gallic acid (3,4,5-trihydroxybenzoic acid) were placed in the flask. 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 8 kPa for 1 hour. After that, the pressure was returned to atmospheric pressure, and the flask was cooled to 160° C., and a mixture of 2133 g of styrene, 533 g of stearyl methacrylate, 114 g of acrylic acid, and 320 g 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 8 kPa for 1 hour. After that, the pressure was returned to atmospheric pressure, and the mixture was cooled to 190°C, 582 g of succinic acid was added, and the mixture was heated to 210°C at 10°C/hr, and then reacted at 4 kPa until the softening point shown in Table 1 was reached, to obtain Resin D-1. The physical properties are shown in Table 1.

<Notes for Table 1>
*1: BPA-PO means a polyoxypropylene (2.2) adduct of bisphenol A. BPA-EO means a polyoxyethylene (2.2) adduct of bisphenol A.
*2: This refers to the molar parts of each monomer constituting the raw material monomer (P) and the bireactive monomer when the alcohol component of the raw material monomer (P) is taken as 100 molar parts.
*3: This refers to the content (mass%) of each monomer constituting the raw material monomer (V) in the total amount of the raw material monomer (V).
*4: Amount (% by mass) relative to 100 parts by mass of the total amount of the polyester resin segment, the addition polymerization resin segment, and the structural units derived from the bireactive monomer
The amount of polyester resin segment was calculated as a theoretical yield excluding the amount of reaction water, and the amount of both reactive monomers was calculated as a theoretical yield excluding the amount of reaction water. The amount of addition polymerization resin segment was calculated assuming that the amount of radical polymerization initiator was included.

[Production of Crystalline Polyester Resin C]
Production Example C1 (Production of Resin C-1)
The inside of a 10 L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer and a thermocouple was replaced with nitrogen, the raw material monomers of the polyester resin shown in Table 2 were added, and 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. Thereafter, 10 g 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 8 kPa for 1 hour, to obtain Resin C-1, a crystalline polyester resin. The physical properties are shown in Table 2.

Production Examples C2, C3, C'4, C5, C'6, and C'7 (Production of Resins C-2, C-3, C'-4, C-5, C'-6, and C'-7)
Resins C-2, C-3, C'-4, C-5, C'-6 and C'-7 were obtained in the same manner as in Production Example C1, except that the raw material monomers for the polyester resin were changed as shown in Table 2. The physical properties are shown in Table 2.

[Production of amorphous resin particle dispersion]
Production Example X1 (Production of Amorphous Resin Particle Dispersion X-1)
In a 2 L vessel equipped with a stirrer, a reflux condenser, a dropping funnel, a thermometer, and a nitrogen inlet tube, 100 g of Resin A-1 shown in Table 3 and 100 g of methyl ethyl ketone were placed and dissolved at 73° C. for 2 hours. 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., 100 g of deionized water was added over 50 minutes while stirring at 200 rpm to cause phase inversion emulsification. While maintaining the temperature of the obtained solution at 73° C., 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 solids concentration became 20% by mass, thereby obtaining resin particle dispersion X-1. The physical properties are shown in Table 3.

Production Examples X2 and X3 (Production of Amorphous Resin Particle Dispersions X-2 and X-3)
Resin particle dispersions X-2 and X-3 were obtained in the same manner as in Production Example X1, except that the resin was changed as shown in Table 3. The physical property values are shown in Table 3.

Production Examples Y1 to Y3, Y'4, Y5, Y'6, and Y'7 (Production of Crystalline Resin Particle Dispersions Y-1 to Y-3, Y'-4, Y-5, Y'-6, and Y'-7)
Resin particle dispersions Y-1 to Y-3, Y'-4, Y-5, Y'-6, and Y'-7 were obtained in the same manner as in Production Example X1, except that the resin was changed as shown in Table 3. The physical property values are shown in Table 3.

Production Example Z1 (Production of Resin Particle Dispersion Z-1)
100 g of Resin B-1 and 100 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 over 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., 200 g of deionized water was added over 50 minutes while stirring at 200 r/min (circumferential speed 63 m/min) to cause phase inversion emulsification. The resulting solution was maintained at 73° C., and 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 content concentration was 20 mass %, thereby obtaining resin particle dispersion Z-1. The physical properties are shown in Table 3.

Production Example Z2 (Production of Resin Particle Dispersion Z-2)
A resin particle dispersion Z-2 was obtained in the same manner as in Production Example Z1, except that Resin B-2 was used instead of Resin B-1.

Production Example S1 (Production of Resin Particle Dispersion S-1)
Resin particle dispersion S-1 was obtained in the same manner as in Production Example Z1, except that Resin B-1 was changed to Resin D-1. The physical properties are shown in Table 3.

[Preparation of release agent particle dispersion]
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 S-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 further dispersed for 20 minutes using an ultrasonic homogenizer "US-600T" (manufactured by Nippon Seiki Seisakusho Co., Ltd.) while maintaining the temperature at 90 to 95°C, and then 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 _D50 of the release agent particles in release agent particle dispersion W-1 was 0.47 μm, and the CV value was 27%.

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-0090" (manufactured by Nippon Seiro Co., Ltd., melting point 90°C). The volume median particle diameter _D50 of the release agent particles in the release agent particle dispersion W-2 was 0.45 μm and the CV value was 28%.

[Preparation of Colorant Particle Dispersion]
Production Example E1 (Production of Colorant Particle Dispersion E-1)
In a 1 L beaker, 75 g of yellow pigment "Paliotol Yellow D1155" (manufactured by BASF Color & Effects Japan, Ltd., C.I. Pigment Yellow 185), 25 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 at room temperature (20°C) for 1 hour at a stirring blade rotation speed of 8000 rpm using a homomixer "T.K.AGI 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 deionized water was added so that the solid content concentration was 20 mass%, to obtain colorant particle dispersion E-1. The physical properties are shown in Table 4.

Production Examples E2, E'3, and E'4 (Production of Colorant Particle Dispersions E-2, E'-3, and E'-4)
Colorant particle dispersions E-2, E'-3 and E'-4 were obtained in the same manner as in Production Example E1, except that the yellow pigment was changed as shown in Table 4. The physical properties are shown in Table 4.

[Toner Production]
Example 1 (Production of Toner 1)
Into a 3 L four-neck flask equipped with a dehydration tube, a stirrer, and a thermocouple, 350 g of amorphous resin particle dispersion X-1, 150 g of crystalline resin particle dispersion Y-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 dropped over 10 minutes at 25° C., and then the temperature was raised to 58° C. over 2 hours and maintained at 58° C. until the volume median particle diameter D ₅₀ of the aggregated particles became 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 Z-1 was added over 90 minutes to obtain a dispersion of aggregated particles 2 in which resin particles were aggregated into aggregated particles 1.
To the obtained dispersion liquid of aggregated particles 2, 50 g of a 20% by mass aqueous solution of sodium salt of naphthalenesulfonic acid-formalin condensate "Demol MS" (manufactured by Kao Corporation) and 1,500 g of deionized water were added. Thereafter, the temperature was raised to 75°C over one 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 for 2 hours at 25° C. Thereafter, the solid content was 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 toner particle 1 are shown in Table 5.
100 parts by mass of toner particles 1, 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, stirred, and passed through a 150 mesh sieve to obtain toner 1.

[Toner Evaluation]
The obtained toner 1 was evaluated as follows.
[Evaluation of Low Temperature Fixability]
A solid image with a toner adhesion amount of 0.43 to 0.45 mg/cm2 on a polypropylene film label "Forest PP Clear FTC50" ⁽ manufactured by UPM Kummene Japan Co., Ltd.) cut to A4 size was printed using a commercially available printer "Microline (registered trademark) 5400" (manufactured by Oki Electric Industry Co., Ltd.) with a length of 50 mm, leaving a margin of 5 mm from the top end of the A4 size film label, without fixing. Next, the same printer with a temperature-variable fixing device was prepared, and a fixing test of the printed matter was performed at each temperature while increasing the temperature of the fixing device from 70°C to 120°C in 5°C increments. A cellophane adhesive tape "UNICEF Cellophane" (manufactured by Mitsubishi Pencil Co., Ltd., width: 18 mm, JIS Z1522:2009) was attached to the image portion of the obtained label print, and the tape was peeled off. The optical reflection density before and after the tape was applied was measured using a reflection densitometer "RD-915" (manufactured by GretagMacbeth), and the temperature of the fixing roll at which the ratio of the two (100 x optical reflection density after peeling/optical reflection density before application) first exceeded 90% was defined as the minimum fixing temperature. The lower the minimum fixing temperature, the better the low-temperature fixing property.

[Evaluation of hardness of printed coating film (fastness of printed coating film)]
A solid image was printed on a polypropylene film label "Forest PP Clear FTC50" (manufactured by UPM Kummene Japan Co., Ltd.) cut to A4 size, with a toner adhesion amount of 0.43 to 0.45 mg/ ^cm2 on the film label, with a length of 50 mm, leaving a margin of 5 mm from the top end of the A4 size film label, without fixing. Next, the same printer was prepared with a temperature-variable fixing device, the fixing device temperature was set to 100°C, and toner 1 was fixed at a speed of 3 seconds per sheet in the A4 portrait direction to form a printed coating film, and a label print was obtained (equivalent to 20 sheets/min in A4 portrait).
The pencil hardness of the printed coating film of the obtained label print was measured in accordance with JIS K5600-5-4 using a pencil scratch coating film hardness tester ("D-NP (model number)" manufactured by Toyo Seiki Seisakusho Co., Ltd.) and pencils for pencil scratch value test (6B, 5B, 4B, 3B, 2B, B, HB, F, H) (manufactured by Mitsubishi Pencil Co., Ltd.). The printed coating film was scratched five times with pencils of each hardness in the order of 6B, 5B, 4B, 3B, 2B, B, HB, F, and H, and the hardest pencil that did not produce scratches three or more times was taken as the pencil hardness of the printed coating film of the label print. "H" is the most excellent in pencil hardness of the printed coating film (fastness of the printed coating film). The pencil hardness of the printed coating film obtained from the toner of the present invention is preferably B or higher. The evaluation results are shown in Table 5.

Examples 2 to 7 and Comparative Examples 1 to 5 (Production of Toners 2 to 7 and 1c to 5c)
Toner particles 2 to 7, toner particles 1c to 5c, and toners 2 to 7 and 1c to 5c were obtained in the same manner as in Example 1, except that the amorphous resin particle dispersion, crystalline resin particle dispersion, and colorant particle dispersion were changed as shown in Table 5. The physical property values of toner particles 2 to 7 and toner particles 1c to 5c are shown in Table 5. The evaluation results of toners 2 to 7 and toners 1c to 5c are also shown in Table 5.

Example 8 (Preparation of Toner 8)
Toner particles 8 and toner 8 were obtained in the same manner as in Example 1, except that the amount of amorphous resin particle dispersion X-1 was changed to 400 g and the amount of crystalline resin particle dispersion Y-1 was changed to 100 g. The physical property values of toner particles 8 and the evaluation results of toner 8 are shown in Table 5.

Example 9 (Preparation of Toner 9)
Toner particles 9 and toner 9 were obtained in the same manner as in Example 1, except that the amount of amorphous resin particle dispersion X-1 was changed to 425 g and the amount of crystalline resin particle dispersion Y-1 was changed to 75 g. The physical property values of toner particles 9 and the evaluation results of toner 9 are shown in Table 5.

Example 10 (Production of Toner 10)
Toner particles 10 and toner 10 were obtained in the same manner as in Example 1, except that the amorphous resin particle dispersion, crystalline resin particle dispersion, and colorant particle dispersion were changed as shown in Table 5, and resin particle dispersion Z-1 was changed to resin particle dispersion Z-2. The physical property values of toner particles 10 are shown in Table 5. The evaluation results of toner 10 are also shown in Table 5.

Example 11 (Production of Toner 11)
80 parts by mass of amorphous polyester resin A-1, 20 parts by mass of crystalline polyester resin C-1, 5 parts by mass of colorant PY185 ("Paliotol Yellow D1155", manufactured by BASF Color & Effect Japan Co., Ltd., C.I. Pigment Yellow 185), 1 part by mass of charge control agent "LR-147" (manufactured by Nippon Carlit Co., Ltd.), and 2 parts by mass of paraffin wax "HNP-9" (manufactured by Nippon Seiro Co., Ltd., melting point 75 ° C.) and 2 parts by mass of paraffin wax "FNP-0090" (manufactured by Nippon Seiro Co., Ltd., melting point 90 ° C.) as release agents were thoroughly stirred with a Henschel mixer, and then melt-kneaded using a co-rotating twin-screw extruder with a kneading section having a total length of 1560 mm, a screw diameter of 42 mm, and a barrel inner diameter of 43 mm. The screw rotation speed was 200 r/min, the heating temperature inside the screw was set to 90° C., the temperature of the kneaded material was 140° C., the feed rate of the kneaded material was 10 kg/h, and the average residence time was about 18 seconds. The kneaded material obtained was cooled from 140° C. to 50° C. in 1.5 hours, rolled and cooled at 50° C. with a cooling roller, and then allowed to stand at 45° C. for 4 hours, and then pulverized and classified with a jet mill to obtain toner particles 11. The physical properties of toner particles 11 are shown in Table 6.
100 parts by mass of toner particles 11, 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, stirred, and passed through a 150 mesh sieve to obtain toner 11. The evaluation results of toner 11 are shown in Table 6.

The toners (Examples 1 to 11) produced using the resin C, the resin A and the pigment specified in the present invention are excellent in low-temperature fixing property, and the printed coating film obtained from the toner has a pencil hardness of "B" or higher, and the printed coating film is excellent in fastness.
In contrast, the toners of Comparative Examples 1 and 2 were produced using the resin C and resin A specified in the present invention, but because a pigment having an NH group amount of less than 6.0 mmol/g was used, the pencil hardness of the printed coating film obtained from the toner was "3B", and sufficient fastness of the printed coating film was not obtained. The toner of Comparative Example 3 was produced using the resin A and pigment specified in the present invention, but because a crystalline polyester resin having an ester group concentration of more than 9.0 mmol/g was used, the pencil hardness of the printed coating film was "6B", and the fastness of the printed coating film was poor. The toner of Comparative Example 4 was produced using the resin A and pigment specified in the present invention, but because a crystalline polyester resin having an ester group concentration of less than 6.5 mmol/g was used, the pencil hardness of the printed coating film was "6B", and the fastness of the printed coating film was poor. The toners of Comparative Examples 4 and 5 were produced using the resin A and pigment specified in the present invention, but because a crystalline polyester resin not containing a structural unit derived from an aliphatic diol component containing ethylene glycol was used, the low-temperature fixability of the toner was poor.

Claims

A toner for developing electrostatic images, comprising a crystalline polyester resin C, an amorphous polyester resin A, and a colorant,
the crystalline polyester resin C contains a structural unit derived from an aliphatic diol component containing ethylene glycol and a structural unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, and has an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g,
The colorant is a pigment having an NH group amount of 6.0 mmol/g or more when the total number of -NH- and -NH2 groups in one molecule is divided by the molecular weight to define the NH group amount.
Toner for developing electrostatic images.
The toner for developing electrostatic images according to claim 1, wherein the crystalline polyester resin C further contains a structural unit derived from a monocarboxylic acid component having 6 to 24 carbon atoms.
The toner for developing electrostatic images according to claim 1 or 2, wherein the colorant is a yellow organic pigment.
The toner for developing electrostatic images according to any one of claims 1 to 3, wherein the colorant contains at least one selected from the group consisting of isoindoline pigments and benzimidazolone pigments.
The toner for developing electrostatic images according to any one of claims 1 to 4, wherein the colorant is at least one selected from C.I. Pigment Yellow 185 and C.I. Pigment Yellow 180.
6. The toner for developing electrostatic images according to claim 1, wherein a difference in solubility parameter between the amorphous polyester resin A and the crystalline polyester resin C is 0.50 (cal/cm 3 ) 1/2 or more and 1.00 (cal/cm 3 ) 1/2 or less.
The toner for developing electrostatic images according to any one of claims 1 to 6, wherein the mass ratio of the content of the amorphous polyester resin A to the content of the crystalline polyester resin C is 60/40 or more and 85/15 or less.
The toner for developing electrostatic images according to any one of claims 1 to 7, wherein the content of the constituent units derived from the aliphatic diol component is 80 mol% or more and 100 mol% or less in the constituent units derived from the alcohol component of the crystalline polyester resin C.
The toner for developing electrostatic images according to any one of claims 1 to 8, wherein the content of the constituent units derived from ethylene glycol is 65 mol % or more and 100 mol % or less in the constituent units derived from the alcohol component of the crystalline polyester resin C.
The toner for developing electrostatic images according to any one of claims 1 to 9, wherein the content of the structural units derived from the aliphatic dicarboxylic acid having 10 to 14 carbon atoms is 70 mol % or more and 100 mol % or less in the structural units derived from the carboxylic acid component of the crystalline polyester resin C.
The toner for developing electrostatic images according to any one of claims 1 to 10, wherein the content of the colorant is 3 parts by mass or more and 25 parts by mass or less per 100 parts by mass of the total of the crystalline polyester resin C and the amorphous polyester resin A.
The toner for developing electrostatic images according to any one of claims 1 to 11, wherein the toner for developing electrostatic images contains toner particles, and the content of the colorant in the toner particles is 3% by mass or more and 25% by mass or less.
The toner for developing electrostatic images according to any one of claims 1 to 12, which has a core-shell structure.
A method for producing a toner for developing an electrostatic image, comprising a step of aggregating and fusing resin particles, the resin particles including a crystalline polyester resin C and an amorphous polyester resin A in the same or different particles, and a colorant in an aqueous medium, the method comprising the steps of:
the crystalline polyester resin C contains a structural unit derived from an aliphatic diol component containing ethylene glycol and a structural unit derived from an aliphatic dicarboxylic acid component having from 10 to 14 carbon atoms, and has an ester group concentration of from 6.5 mmol/g to 9.0 mmol/g,
The colorant is a pigment having an NH group amount of 6.0 mmol/g or more when the total number of -NH- and -NH2 groups in one molecule is divided by the molecular weight to define the NH group amount.
A method for producing a toner for developing electrostatic images.