Toner binder resin composition

Abstract

To provide a toner binder resin composition excellent in image density even with an amount of low adhesion, electrostatic charge image development toner containing the toner binder resin composition, and a manufacturing method of the electrostatic charge image development toner.SOLUTION: A toner binder resin composition contains: a crystalline polyester resin (A); and a non-crystalline polyester resin (B), in which the crystalline polyester resin (A) is a polycondensation product of a raw material monomer (a) including aliphatic diol, an aliphatic dicarboxylic acid, and at least one kind selected from a group formed of aliphatic monoalcohol having 10 to 22 carbon atoms and an aliphatic monocarboxylic acid having 10 to 22 carbon atoms, the non-crystalline polyester resin (B) includes: a linear polyester resin (B1); and a non-linear polyester resin (B2), and at least one of the linear polyester resin (B1) and the non-linear polyester resin (B2) is a silicone modified polyester resin.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a binder resin composition for a toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like, a toner for developing an electrostatic image containing the binder resin composition for a toner, and a method for producing the toner for developing an electrostatic image. [Background technology]

[0002] In the field of electrophotography, with the development of electrophotographic systems, there is a demand for the development of toners for developing electrostatic images (hereinafter, simply referred to as "toners") that can meet the demands of higher image quality and higher speeds. In addition, in recent years, there has been a demand for a reduction in the amount of toner attached in printing in order to reduce power consumption and conserve resources in toner printing. However, if you try to reduce the amount of toner adhesion, the toner cannot cover the paper surface sufficiently during fixing, resulting in a decrease in image density, so it is necessary to reduce the viscosity of the toner so that it can wet and spread sufficiently. Crystalline polyesters are used to reduce the viscosity of toner, but increasing the amount of crystalline polyester added leads to deterioration of the storage stability and durability of the toner, so low-viscosity crystalline polyesters are being developed.

[0003] For example, Patent Document 1 describes a toner resin containing a polyester resin (I) composed of a linear polyester (A) and a nonlinear polyester (B), which is a polycondensation polyester resin of a carboxylic acid component and an alcohol component, containing 40 mol % or more of one or more selected from aliphatic polycarboxylic acids having 9 to 30 carbon atoms and their ester-forming derivatives, and has an SP value of 9.0 to 10.5 (cal / cm 3 ) 1 / 2 The document describes a toner resin characterized in that (A) contains 5% by weight or more of the crystalline polyester (A1) represented by the formula: Furthermore, Patent Document 2 describes a toner having toner particles containing a binder resin and a crystalline polyester, characterized in that the binder resin contains a polyester having a silicone structure. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-63987 A [Patent Document 2] JP 2021-60582 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, it was found that in a toner using a toner resin containing the low-viscosity crystalline polyester described in Patent Document 1, the toner spreads better when fixed, but the crystalline polyester bleeds out and crystallizes on the surface of the printed image due to its low SP value, causing the image to turn white, resulting in insufficient image density. Also, in a toner using a toner binder resin described in Patent Document 2, the recrystallized crystalline polyester is present on the surface of the fixed image, causing the image to turn white, resulting in insufficient image density.

[0006] The present invention relates to a binder resin composition for toners which has excellent image density even in a low adhesion amount, a toner for developing electrostatic images which contains the binder resin composition for toners, and a method for producing the toner for developing electrostatic images. [Means for solving the problem]

[0007] The present invention relates to the following [1] to [3]. [1] A binder resin composition for toner, comprising a crystalline polyester resin (A) and an amorphous polyester resin (B), the crystalline polyester resin (A) is a polycondensate of raw material monomers (a) including an aliphatic diol, an aliphatic dicarboxylic acid, and at least one selected from the group consisting of an aliphatic monocarboxylic acid having from 10 to 22 carbon atoms and an aliphatic monoalcohol having from 10 to 22 carbon atoms; The amorphous polyester resin (B) comprises a linear polyester resin (B1) and a nonlinear polyester resin (B2), At least one of the linear polyester resin (B1) and the nonlinear polyester resin (B2) is a silicone-modified polyester resin which is a reaction product of a raw material monomer (b) containing an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid, and at least one selected from a modified silicone having a repeating unit represented by formula (1) and a repeating unit represented by formula (2) and a modified silicone having a repeating unit represented by formula (2) and a structure represented by formula (3). A binder resin composition for toner. [ka] [In formula (1), R is each independently a hydrocarbon group having 1 to 6 carbon atoms, R' is each independently an alkylene group having 1 to 10 carbon atoms, a is 1 or 0, X is each independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site.] [ka] [In formula (2), each R is independently a hydrocarbon group having 1 to 6 carbon atoms, and * is a bonding site.] *-SiR 3-b (R''-X) b (3) [In formula (3), R is each independently a hydrocarbon group having 1 to 6 carbon atoms, R″ is each independently an alkylene group having 1 to 10 carbon atoms, b is an integer of 1 to 3, X is each independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site.] [2] A toner for developing electrostatic images, comprising the binder resin composition for toners according to [1] above and a colorant. [3] A method for producing a toner for developing an electrostatic image, comprising the steps of melt-kneading the binder resin composition for a toner according to [1] to obtain a melt-kneaded product, and pulverizing and classifying the melt-kneaded product to obtain toner base particles. Effect of the Invention

[0008] According to the present invention, it is possible to provide a binder resin composition for a toner which has excellent image density even in a low adhesion amount, a toner for developing electrostatic images containing the binder resin composition for a toner, and a method for producing the toner for developing electrostatic images. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] [Binder resin composition for toner] A toner binder resin composition according to one embodiment of the present invention is a toner binder resin composition containing a crystalline polyester resin (A) and an amorphous polyester resin (B). The crystalline polyester resin (A) is a polycondensate of raw material monomers (a) containing an aliphatic diol, an aliphatic dicarboxylic acid, and at least one selected from the group consisting of an aliphatic monocarboxylic acid having 10 to 22 carbon atoms and an aliphatic monoalcohol having 10 to 22 carbon atoms. The amorphous polyester resin (B) contains a linear polyester resin (B1) and a nonlinear polyester resin (B2), and at least one of the linear polyester resin (B1) and the nonlinear polyester resin (B2) is a silicone-modified polyester resin that is a reaction product of raw material monomers (b) containing an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid, and a specific modified silicone. According to the above constitution, it is possible to provide a binder resin composition for toner which gives a toner exhibiting excellent image density even with a low adhesion amount.

[0010] The reason why the present invention has an effect is not clear, but is thought to be as follows. The toner binder resin composition of the present invention contains a crystalline polyester resin (A) (hereinafter also referred to as "resin (A)") which is a polycondensate of raw material monomer (a) containing an aliphatic diol, an aliphatic dicarboxylic acid, and at least one selected from the group consisting of an aliphatic monocarboxylic acid having 10 to 22 carbon atoms and an aliphatic monoalcohol having 10 to 22 carbon atoms. By containing a structure derived from the monocarboxylic acid and / or the monoalcohol, the resin (A) has high compatibility with the amorphous polyester resin (B) (hereinafter also referred to as "resin (B)") and is considered to be able to increase the coverage rate of the toner since the resin (A) is highly compatible with the amorphous polyester resin (B) and allows the toner to spread widely during fixing. In addition, the resin (A) is easily crystallized, and after melting during fixing, it crystallizes before moving to the image surface, and therefore it is considered that the localization of the resin (A) on the image surface during fixing of the toner can be suppressed. In addition, the resin (B) contained in the toner binder resin composition of the present invention softens at a low temperature by containing a linear polyester resin (B1) (hereinafter also referred to as "resin (B1)") and a nonlinear polyester resin (B2) (hereinafter also referred to as "resin (B2)"). Furthermore, at least one of the resins (B1) and (B2) contained in the resin (B) contains a hydrophobic modified silicone moiety, and therefore has a significantly low affinity with a paper surface having a hydrophilic surface. Therefore, when the toner is fixed to the paper surface by heating, the resin (B1) and / or the resin (B2) containing the modified silicone moiety are more likely to localize on the image surface than the resin (A). From the above, it is considered that the resin (B) further suppresses the localization of the resin (A) on the image surface when the toner is fixed. In this way, the toner using the binder resin composition for toner of the present invention containing resin (A) and resin (B) is considered to have excellent image density even at a low adhesion amount, since whitening of the image due to crystallization of resin (A) on the image surface is suppressed. The above-mentioned mechanism regarding the effect of the present invention is merely a presumption, and the present invention is not limited thereto.

[0011] The definitions of various terms used in this specification are given below. Whether a resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is defined as the ratio of the softening point of the resin to the maximum endothermic peak temperature (softening point (°C) / maximum endothermic peak temperature (°C)) in the measurement method described in the examples below. A crystalline resin is one with a crystallinity index of 0.6 or more and 1.4 or less. An amorphous resin is one in which no endothermic peak is observed, or, if observed, has a crystallinity index of less than 0.6 or more than 1.4. The crystallinity index can be appropriately adjusted by the types and ratios of raw material monomers, as well as production conditions such as reaction temperature, reaction time, and cooling rate. 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 an acid, and alkyl esters of each carboxylic acid (alkyl groups having 1 to 3 carbon atoms). Volume Median Particle Size (D 50 )" is the particle size at which the cumulative volume frequency calculated by volume fraction is 50% starting from the smallest particle size. "Bisphenol A" is 2,2-bis(4-hydroxyphenyl)propane.

[0012] [Crystalline polyester resin (A)] The crystalline polyester resin (A) contained in the binder resin composition for toner of the present invention is a polycondensate of raw material monomer (a) containing an aliphatic diol, an aliphatic dicarboxylic acid, and at least one selected from the group consisting of an aliphatic monocarboxylic acid having from 10 to 22 carbon atoms (hereinafter also referred to as an "aliphatic monocarboxylic acid") and an aliphatic monoalcohol having from 10 to 22 carbon atoms (hereinafter also referred to as an "aliphatic monoalcohol").

[0013] <Alcohol content> The raw material monomer (a) contains, as an alcohol component, an aliphatic diol and, as necessary, an aliphatic monoalcohol having 10 or more and 22 or less carbon atoms.

[0014] (Aliphatic diol) The aliphatic diol contained in the raw material monomer (a) is preferably an α,ω-aliphatic diol. The aliphatic diol has preferably 2 or more, more preferably 4 or more, and even more preferably 6 or more carbon atoms, and preferably 16 or less, more preferably 14 or less, and even more preferably 12 or less carbon atoms. Examples of the aliphatic diol include α,ω-aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, and 1,14-tetradecanediol; and aliphatic diols other than α,ω-aliphatic diols such as 1,2-propanediol and neopentyl glycol. Among these, α,ω-aliphatic diols are preferred, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, and 1,10-decanediol are more preferred, and ethylene glycol and 1,10-decanediol are even more preferred. By using ethylene glycol as the aliphatic diol, the crystallization of the resin (A) is accelerated, and localization of the resin (A) during fixing can be suppressed.

[0015] When the raw material monomer (a) does not contain an aliphatic monoalcohol, the amount of the aliphatic diol in the raw material monomer (a) 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 preferably 100 mol% or less, more preferably 100 mol% in the alcohol component from the viewpoint of improving the image density of the toner. Also, when the raw material monomer (a) contains an aliphatic monoalcohol, the amount of the aliphatic diol in the raw material monomer (a) is preferably 8 mol% or more, more preferably 10 mol% or more, even more preferably 12 mol% or more, and preferably 80 mol% or less, more preferably 77 mol% or less, even more preferably 75 mol% or less, in the alcohol component.

[0016] (Aliphatic monoalcohols with carbon numbers between 10 and 22) As the aliphatic monoalcohol having 10 to 22 carbon atoms contained in the raw material monomer (a), from the viewpoint of improving the image density of the toner, an aliphatic monoalcohol having 16 to 22 carbon atoms is preferable, and a straight-chain aliphatic monoalcohol having 16 to 22 carbon atoms is more preferable. Preferred examples of aliphatic monoalcohols include 1-decanol, 1-undecanol, 1-dodecanol (lauryl alcohol), 1-tridecanol, 1-tetradecanol (myristyl alcohol), 1-pentadecanol, 1-hexadecanol (cetanol), 1-heptadecanol, 1-octadecanol (stearyl alcohol), 1-nonadecanol, 1-eicosanol (arachidyl alcohol), 1-heneicosanol, and 1-docosanol (behenyl alcohol).

[0017] From the viewpoint of improving the image density of the toner, the amount of the aliphatic diol in the raw material monomer (a) is preferably 20 mol % or more, more preferably 23 mol % or more, even more preferably 25 mol % or more, and is preferably 92 mol % or less, more preferably 90 mol % or less, even more preferably 88 mol % or less, in the alcohol component.

[0018] The alcohol component may contain other alcohol components different from the aliphatic diol and the aliphatic monoalcohol. Examples of the other alcohol components include alkylene oxide adducts of aromatic diols such as alkylene oxide adducts of bisphenol A; trihydric or higher alcohols such as glycerin, pentaerythritol, and trimethylolpropane; and aliphatic monoalcohols having 9 or less carbon atoms or 23 or more carbon atoms such as 1-octanol (capryl alcohol) and 1-tetracosanol. One or more of these alcohol components may be used.

[0019] <Carboxylic acid component> The raw material monomer (a) contains, as a carboxylic acid component, an aliphatic dicarboxylic acid and, as necessary, an aliphatic monocarboxylic acid having from 10 to 22 carbon atoms.

[0020] (Aliphatic dicarboxylic acids) The aliphatic dicarboxylic acid contained in the raw material monomer (a) is preferably a straight-chain aliphatic dicarboxylic acid. The aliphatic dicarboxylic acid preferably has 8 or more carbon atoms and preferably has 16 or less carbon atoms. Preferred examples of the aliphatic dicarboxylic acid include sebacic acid, dodecanedioic acid, and tetradecanedioic acid. Among these, dodecanedioic acid and tetradecanedioic acid are more preferred.

[0021] When the raw material monomer (a) does not contain an aliphatic monocarboxylic acid, the amount of the aliphatic dicarboxylic acid in the raw material monomer (a) 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 preferably 100 mol% or less, more preferably 100 mol% in the carboxylic acid component from the viewpoint of improving the image density of the toner. Also, when the raw material monomer (a) contains an aliphatic monocarboxylic acid, the amount of the aliphatic dicarboxylic acid in the raw material monomer (a) is preferably 8 mol% or more, more preferably 10 mol% or more, even more preferably 12 mol% or more, and preferably 80 mol% or less, more preferably 75 mol% or less, even more preferably 70 mol% or less, in the carboxylic acid component.

[0022] (Aliphatic monocarboxylic acid having 10 to 22 carbon atoms) As the aliphatic monocarboxylic acid having 10 to 22 carbon atoms contained in the raw material monomer (a), from the viewpoint of improving the image density of the toner, an aliphatic monocarboxylic acid having 16 to 22 carbon atoms is preferable, and a straight-chain aliphatic monocarboxylic acid having 16 to 22 carbon atoms is more preferable. Examples of preferred aliphatic monocarboxylic acids include decanoic acid, undecanoic acid, dodecanoic acid (lauric acid), tridecanoic acid, tetradecanoic acid (myristic acid), pentadecanoic acid, hexadecanoic acid (palmitic acid), heptadecanoic acid (margaric acid), octadecanoic acid (stearic acid), nonadecanoic acid, eicosanoic acid (arachidic acid), heneicosanoic acid, and docosanoic acid (behenic acid). Among these, behenic acid and stearic acid are more preferred.

[0023] From the viewpoint of improving the image density of the toner, the amount of the aliphatic monocarboxylic acid in the raw material monomer (a) is preferably 20 mol % or more, more preferably 25 mol % or more, even more preferably 30 mol % or more, and is preferably 92 mol % or less, more preferably 90 mol % or less, even more preferably 88 mol % or less, in the carboxylic acid component.

[0024] The carboxylic acid component may contain other carboxylic acid components different from aliphatic dicarboxylic acids and aliphatic monocarboxylic acids. Examples of other carboxylic acid components include aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid; polyvalent carboxylic acids having three or more carboxylic acids, and aliphatic monocarboxylic acids having 9 or less carbon atoms or 23 or more carbon atoms, such as octanoic acid (caprylic acid) and tetracosanoic acid (lignoceric acid). These carboxylic acid components may be used alone or in combination.

[0025] 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 1.5 or less, more preferably 1.4 or less.

[0026] The raw material monomer (a) preferably contains an aliphatic diol, an aliphatic dicarboxylic acid, and an aliphatic monocarboxylic acid, and the content of the aliphatic monocarboxylic acid in the raw material monomer (a) is preferably 10 mol % or more, more preferably 12 mol % or more, even more preferably 15 mol % or more, and is preferably 65 mol % or less, more preferably 60 mol % or less, even more preferably 58 mol % or less, from the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion.

[0027] (Method for producing resin (A)) The resin (A) is produced, for example, by a method of polycondensing a raw material monomer (a). In the polycondensation reaction, if necessary, an esterification catalyst such as tin(II) di(2-ethylhexanoate), dibutyltin oxide, or titanium diisopropylate bistriethanolamine may be used in an amount of 0.01 to 5 parts by mass per 100 parts by mass of the total amount of aliphatic diol, aliphatic dicarboxylic acid, aliphatic monoalcohol, and aliphatic monocarboxylic acid; or an esterification promoter such as gallic acid (same as 3,4,5-trihydroxybenzoic acid) may be used in an amount of 0.001 to 0.5 parts by mass per 100 parts by mass of the total amount of aliphatic diol, aliphatic dicarboxylic acid, aliphatic monoalcohol, and aliphatic monocarboxylic acid. When a monomer having an unsaturated bond such as fumaric acid is used in polycondensation, a radical polymerization inhibitor may be used, if necessary, in an amount of preferably 0.001 to 0.5 parts by mass per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. An example of the radical polymerization inhibitor is 4-tert-butylcatechol. The reaction temperature is preferably 120° C. or higher, more preferably 160° C. or higher, even more preferably 180° C. or higher, and is preferably 250° C. or lower, more preferably 240° C. or lower. The reaction may be carried out in an inert gas atmosphere.

[0028] (Physical properties of resin (A)) The acid value of the resin (A) is preferably 5 mgKOH / g or less, more preferably 4.5 mgKOH / g or less, and even more preferably 4 mgKOH / g or less. The hydroxyl value of the resin (A) is preferably 9 mgKOH / g or less, more preferably 8.5 mgKOH / g or less, and even more preferably 8.3 mgKOH / g or less. The sum of the acid value and the hydroxyl value of the resin (A) is preferably 10 mgKOH / g or less, more preferably 9.8 mgKOH / g or less, and even more preferably 9.7 mgKOH / g or less.

[0029] The melting point of resin (A) is preferably 50°C or higher, more preferably 55°C or higher, and even more preferably 60°C or higher, and from the viewpoint of further improving low-temperature fixability, is preferably 100°C or lower, more preferably 95°C or lower, and even more preferably 90°C or lower. The softening point of the resin (A) is preferably 55° C. or higher, more preferably 60° C. or higher, even more preferably 65° C. or higher, and is preferably 105° C. or lower, more preferably 100° C. or lower, even more preferably 95° C. or lower.

[0030] From the viewpoint of further enhancing the compatibility between resin (A) and resin (B) during fixing, the weight average molecular weight of resin (A) is preferably 500 or more, more preferably 1,000 or more, even more preferably 1,500 or more, and is preferably 8,000 or less, more preferably 6,000 or less, even more preferably 5,000 or less.

[0031] The acid value, hydroxyl value, melting point, softening point, and weight average molecular weight of the resin (A) can be appropriately adjusted by the type and amount of the raw material monomer (a) and production conditions such as reaction temperature, reaction time, cooling rate, etc., and are determined by the method described in the Examples below. When two or more types of resin (A) are used in combination, it is preferable that the acid value, hydroxyl value, melting point, softening point, and weight average molecular weight of the resin (A) obtained as a mixture thereof are each within the above-mentioned ranges.

[0032] [Amorphous polyester resin (B)] Resin (B) comprises a linear polyester resin (B1) and a nonlinear polyester resin (B2), and at least one of resin (B1) and resin (B2) is a silicone-modified polyester resin which is a reaction product of raw material monomer (b) which comprises an alcohol component containing a dihydric or higher alcohol, a carboxylic acid component containing a dihydric or higher carboxylic acid, and a modified silicone as described below.

[0033] <Linear polyester resin (B1)> When the resin (B1) is not a silicone-modified polyester resin, the resin (B1) is a reaction product of raw material monomer (b1-1) containing an alcohol component containing a dihydric alcohol and a carboxylic acid component containing a divalent carboxylic acid. When the resin (B1) is a silicone-modified polyester resin, the resin (B1) is a silicone-modified polyester resin which is a reaction product of raw material monomer (b1-2) containing an alcohol component containing a dihydric alcohol, a carboxylic acid component containing a divalent carboxylic acid, and the modified silicone shown below. From the viewpoint of improving the image density of the toner, the resin (B1) is preferably a silicone-modified polyester resin.

[0034] (Alcohol content) Examples of the dihydric alcohol contained in the raw material monomer (b1-1) and the raw material monomer (b1-2) include an alkylene oxide adduct of an aromatic diol, a linear or branched aliphatic diol, and an alicyclic diol. Among these, an alkylene oxide adduct of an aromatic diol or a linear or branched aliphatic diol is preferred, and an alkylene oxide adduct of an aromatic diol is more preferred. The content of the dihydric alcohol in the alcohol component is preferably 80 mol % or more, more preferably 90 mol % or more, and even more preferably 95 mol % or more, and 100 mol % or less.

[0035] The alkylene oxide adduct of an aromatic diol is preferably an alkylene oxide adduct of bisphenol A, more preferably an alkylene oxide adduct of formula (I):

[0036] [ka] (In the formula, OR 1 and R 2 O is an oxyalkylene group, and R 1 and R 2 are each independently an ethylene group or a propylene group, x and y are each an 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 include a propylene oxide adduct of bisphenol A and an ethylene oxide adduct of bisphenol A. One or more of these may be used. Among these, a combination of a propylene oxide adduct of bisphenol A and an ethylene oxide adduct of bisphenol A is preferred. When an alkylene oxide adduct of bisphenol A is contained, the amount thereof in the alcohol component is preferably 70 mol % or more, more preferably 90 mol % or more, even more preferably 95 mol % or more, and is 100 mol % or less, even more preferably 100 mol %.

[0037] As the linear or branched aliphatic diol, an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferred. The aliphatic diol having a hydroxyl group bonded to a secondary carbon atom preferably has 3 or more and 4 or less carbon atoms. Examples of aliphatic diols having a hydroxyl group bonded to a secondary carbon atom include 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, and 2,3-butanediol. When an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is used as the alcohol component, the amount thereof in the alcohol component is preferably 70 mol % or more, more preferably 90 mol % or more, even more preferably 95 mol % or more, and is 100 mol % or less, even more preferably 100 mol %.

[0038] Other linear or branched aliphatic diols include, for example, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, and neopentyl glycol.

[0039] Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane] and adducts of hydrogenated bisphenol A with alkylene oxides having 2 to 4 carbon atoms (average number of moles added: 2 to 12). These alcohol components may be used alone or in combination of two or more.

[0040] (Carboxylic acid component) Examples of the divalent carboxylic acid contained in the raw material monomer (b1-1) and the raw material monomer (b1-2) include aromatic dicarboxylic acids, linear or branched aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Among these, aromatic dicarboxylic acids are preferred. The content of the divalent carboxylic acid in the carboxylic acid component is preferably 80 mol % or more, more preferably 90 mol % or more, and further preferably 95 mol % or more, and 100 mol % or less.

[0041] 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 the aromatic dicarboxylic acid in the carboxylic acid component is preferably 80 mol % or more, more preferably 90 mol % or more, and further preferably 95 mol % or more, and 100 mol % or less.

[0042] The linear or branched aliphatic dicarboxylic acid has preferably 2 or more, more preferably 4 or more, even more preferably 8 or more, even more preferably 10 or more carbon atoms, and preferably 22 or less, more preferably 16 or less. Examples of linear or branched aliphatic dicarboxylic acids include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, tetradecanedioic acid, succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms, or anhydrides or alkyl esters thereof having 1 to 3 carbon atoms. Examples of succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, and octenylsuccinic acid. Among these, fumaric acid is preferred. When a linear or branched aliphatic dicarboxylic acid is contained, the amount thereof in the carboxylic acid component is preferably 10 mol % or more, more preferably 20 mol % or more, even more preferably 30 mol % or more, and is preferably 90 mol % or less, more preferably 80 mol % or less.

[0043] The ratio of the carboxy groups of the carboxylic acid component to the hydroxy groups of the alcohol component (COOH groups / OH groups) is preferably 0.6 or more, more preferably 0.7 or more, and is preferably 1.1 or less, more preferably 1.0 or less.

[0044] From the viewpoint of adjusting the molecular weight and softening point of the polyester resin, the alcohol component may appropriately contain a monohydric alcohol, and the carboxylic acid component may appropriately contain a monovalent carboxylic acid compound.

[0045] (Modified silicone) The raw material monomer (b1-2) contains at least one selected from modified silicones having a repeating unit represented by formula (1) and a repeating unit represented by formula (2) and modified silicones having a repeating unit represented by formula (2) and a structure represented by formula (3). From the viewpoint of improving the image density of the toner, the modified silicone is preferably a modified silicone having a repeating unit represented by formula (1) and a repeating unit represented by formula (2).

[0046] [ka] [In formula (1), R is each independently a hydrocarbon group having 1 to 6 carbon atoms, R' is each independently an alkylene group having 1 to 10 carbon atoms, a is 1 or 0, X is each independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site.]

[0047] [ka] [In formula (2), each R is independently a hydrocarbon group having 1 to 6 carbon atoms, and * is a bonding site.]

[0048] *-SiR 3-b (R''-X) b (3) [In formula (3), R is each independently a hydrocarbon group having 1 to 6 carbon atoms, R″ is each independently an alkylene group having 1 to 10 carbon atoms, b is an integer of 1 to 3, X is each independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site with the repeating unit represented by formula (2)]

[0049] The repeating unit represented by formula (1) and the repeating unit represented by formula (2) may be random or block, and are not particularly limited.

[0050] In formulas (1) to (3), the hydrocarbon group for R has 6 or less carbon atoms, preferably 4 or less, more preferably 3 or less, even more preferably 2 or less, and even more preferably 1 carbon atom. Examples of the hydrocarbon group for R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, a pentyl group, and a phenyl group. Among these, a methyl group is preferable.

[0051] In formula (1) and formula (3), the number of carbon atoms in the alkylene group of R' and R'' is 10 or less, preferably 8 or less, more preferably 5 or less, even more preferably 4 or less, still more preferably 3 or less, and preferably 1 or more. Examples of the alkylene group of R' and R'' include a methanediyl group, an ethane-1,2-diyl group, an ethane-1,1-diyl group, an n-propane-1,3-diyl group, and an n-propane-1,2-diyl group. Among these, a methanediyl group, an ethane-1,2-diyl group, an n-propane-1,3-diyl group, and an n-propane-1,2-diyl group are preferred.

[0052] Each X is independently a group having an amino group, a carboxy group, an epoxy group, or a hydroxy group, and is preferably an amino group, a hydroxy group, a hydroxyalkyloxy group, a carboxy group, a carboxyalkyloxy group, an epoxy group, a glycidyl group, a glycidyloxy group, or an alicyclic epoxy group. The hydroxyalkyloxy group may have a plurality of hydroxy groups, and the carboxyalkyloxy group may have a plurality of carboxy groups. Among them, from the viewpoint of reactivity with the carboxy group of a divalent or higher carboxylic acid, it is preferable that X is a group having an amino group.

[0053] The modified silicone contains 40 or less repeating units represented by formula (1), preferably 20 or less, more preferably 10 or less, and more preferably 1 or more repeating units. The repeating units represented by formula (2) are contained in an amount of 500 or less, preferably 450 or less, more preferably 400 or less, and preferably 10 or more, preferably 30 or more, more preferably 50 or more.

[0054] The functional group equivalent of the modified silicone is preferably 300 g / mol or more, more preferably 500 g / mol or more, even more preferably 1,000 g / mol or more, even more preferably 2,000 g / mol or more, and preferably 10,000 g / mol or less, more preferably 8,000 g / mol or less, even more preferably 6,000 g / mol or less. The functional group equivalent weight means the mass of the modified silicone per mole of functional group.

[0055] The kinetic viscosity of the modified silicone is preferably 20 mm at 25° C. from the viewpoint of improving the image density of the toner. 2 / s or more, preferably 90 mm 2 / s or more, more preferably 1000 mm 2 / s or more, and preferably 10,000 mm 2 / s or less, preferably 5,000 mm 2 / s or less, and more preferably 2,000 mm 2 / s or less. The kinetic viscosity of the modified silicone may be a catalog value, or may be measured using, for example, a fully automatic microkinetic viscometer (manufactured by Viscotec Co., Ltd.).

[0056] The modified silicones mentioned above include, for example, modified silicones having an amino group on the side chain (commercially available products include, for example, "KF-864" and "KF-865" (manufactured by Shin-Etsu Chemical Co., Ltd.)), modified silicones having amino groups on both ends (commercially available products include, for example, "KF-8008" and "KF-8012" (manufactured by Shin-Etsu Chemical Co., Ltd.)), modified silicones having an amino group on one end; modified silicones having a carboxy group on the side chain (commercially available products include, for example, "X-22-3701E" (manufactured by Shin-Etsu Chemical Co., Ltd.) and "BY16-880" (manufactured by Dow Corning Toray Co., Ltd.)), modified silicones having carboxy groups on both ends (commercially available products include, for example, "X-22-162C" (manufactured by Shin-Etsu Chemical Co., Ltd.)), modified silicones having a carboxy group on one end (commercially available products include, for example, "X-22-3710" (manufactured by Shin-Etsu Chemical Co., Ltd.)); Modified silicones having epoxy groups at the side chains (commercially available products include "X-22-343" (Shin-Etsu Chemical Co., Ltd.)), modified silicones having epoxy groups at both ends (commercially available products include "X-22-163B" and "X-22-169B" (Shin-Etsu Chemical Co., Ltd.)), modified silicones having epoxy groups at one end (commercially available products include "X-22-173BX" (Shin-Etsu Chemical Co., Ltd.)); modified silicones having hydroxyl groups at the side chains (commercially available products include "X-22-4015" and "X-22-4039" (Shin-Etsu Chemical Co., Ltd.)), modified silicones having hydroxyl groups at both ends (commercially available products include "KF-6003" and "KF-6002" (Shin-Etsu Chemical Co., Ltd.)), and modified silicones having hydroxyl groups at one end (commercially available products include "X-22-170BX" and "X-22-170DX" (Shin-Etsu Chemical Co., Ltd.)).

[0057] When the modified silicone has a group containing an amino group, in the repeating unit represented by formula (1) and the structure represented by formula (3), *-(R') a Examples of the group represented by -X and the group represented by -(R''-X) include the following substituents 1a-1 to 1a-3.

[0058] [ka]

[0059] When the modified silicone is a modified silicone having a group containing a hydroxyl group, in the repeating unit represented by formula (1) and the structure represented by formula (3), *-(R') a Examples of the group represented by -X and the group represented by -(R''-X) include the following substituents 1b-1 to 1b-3. Among these, the substituent 1b-1 or the substituent 1b-2 is preferred, and the substituent 1b-1 is more preferred.

[0060] [ka]

[0061] When the modified silicone is a modified silicone having a group containing an epoxy group, in the repeating unit represented by formula (1) and the structure represented by formula (3), X and Y are preferably a glycidyl group, a glycidyloxy group, and an alicyclic epoxy group, and *-(R') a Examples of the group represented by -X and the group represented by -(R''-X) include the following substituents 1b-4 to 1b-6. Among these, the substituent 1b-4 is preferred.

[0062] [ka]

[0063] When the modified silicone is a modified silicone having a group containing a carboxy group, in the repeating unit represented by formula (1) and the structure represented by formula (3), X and Y are preferably a carboxy group or a carboxyalkyloxy group, and *-(R') a Examples of the group represented by -X and the group represented by -(R''-X) include the following substituent 1b-7.

[0064] [ka]

[0065] <Nonlinear polyester resin (B2)> When the resin (B2) is not a silicone-modified polyester resin, the resin (B2) is a reaction product of raw material monomer (b2-1) containing an alcohol component containing a dihydric or higher alcohol and a carboxylic acid component containing a dihydric or higher carboxylic acid. When the resin (B2) is a silicone-modified polyester resin, the resin (B2) is a reaction product of raw material monomer (b2-2) containing an alcohol component containing a dihydric or higher alcohol and a modified silicone. The raw material monomers (b2-1) and (b2-2) contain either or both of a trihydric or higher polyhydric alcohol and a trihydric or higher polycarboxylic acid, and preferably contain either one.

[0066] (Alcohol content) Examples of trihydric or higher polyhydric alcohols contained in the raw material monomer (b2-1) and the raw material monomer (b2-2) include glycerin, pentaerythritol, trimethylolpropane, and sorbitol. These alcohol components may be used alone or in combination of two or more. When the alcohol component contains a trihydric or higher polyhydric alcohol, the content of the trihydric or higher polyhydric alcohol in the alcohol component is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and preferably 30 mol% or less, more preferably 25 mol% or less, even more preferably 20 mol% or less.

[0067] As the dihydric alcohol contained in the raw material monomer (b2-1) and the raw material monomer (b2-2), the dihydric alcohols exemplified as the alcohol component of the resin (B1) can be used, and the preferred ranges are also the same. When the alcohol component contains a trihydric or higher polyhydric alcohol, the content of the dihydric alcohol in the alcohol component is preferably 70 mol% or more, more preferably 75 mol% or more, even more preferably 80 mol% or more, and preferably 95 mol% or less, more preferably 90 mol% or less, even more preferably 85 mol% or less. On the other hand, when the alcohol component does not contain a polyhydric alcohol having a hydricity of three or more, the content of the dihydric alcohol in the alcohol component is preferably 90 mol% or more, more preferably 95 mol% or more, and preferably 100 mol% or less, more preferably 100 mol%.

[0068] <Carboxylic acid component> The tri- or higher carboxylic acid contained in the raw material monomer (b2-1) and the raw material monomer (b2-2) is preferably a tricarboxylic acid, such as trimellitic acid. When the carboxylic acid component contains a polyvalent carboxylic acid having three or more carboxylic acids, the content of the trivalent or higher carboxylic acids 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 30 mol% or less, more preferably 25 mol% or less, even more preferably 20 mol% or less.

[0069] As the divalent carboxylic acid contained in the raw material monomer (b2-1) and the raw material monomer (b2-2), the divalent carboxylic acid exemplified as the carboxylic acid of the resin (B1) can be used. A combination of an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid is preferred, a combination of terephthalic acid and a succinic acid substituted with an aliphatic hydrocarbon group having from 1 to 20 carbon atoms is more preferred, and a combination of terephthalic acid and dodecenylsuccinic acid is even more preferred. When the carboxylic acid component contains a trivalent or higher polycarboxylic acid, the content of the divalent carboxylic acid 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 preferably 95 mol% or less, more preferably 90 mol% or less, even more preferably 85 mol% or less. On the other hand, when the carboxylic acid component does not contain a polycarboxylic acid having three or more carboxylic acids, the content of the dicarboxylic acid in the alcohol component is preferably 90 mol% or more, more preferably 95 mol% or more, and preferably 100 mol% or less, more preferably 100 mol%.

[0070] The ratio of the carboxy groups of the carboxylic acid component to the hydroxy groups of the alcohol component (COOH groups / OH groups) is preferably 0.8 or more, more preferably 0.9 or more, and is preferably 1.2 or less, more preferably 1.1 or less.

[0071] From the viewpoint of adjusting the molecular weight and softening point of the polyester resin, the alcohol component may appropriately contain a monohydric alcohol, and the carboxylic acid component may appropriately contain a monovalent carboxylic acid compound.

[0072] (Modified silicone) The raw material monomer (b2-2) contains a modified silicone in addition to the alcohol component and the carboxylic acid component. The modified silicone may be the same as that shown in the resin (B1), and the preferred range is also the same.

[0073] (Method for producing resin (B)) When the resin (B1) or the resin (B2) is not a silicone-modified polyester resin, the resin (B1) and the resin (B2) are produced by a method of polycondensing the raw material monomer (b1-1) and the raw material monomer (b2-1), respectively. The esterification catalyst, esterification promoter, and radical polymerization inhibitor used in the polycondensation may be the same as those described in the method for producing resin (A). In addition, the reaction conditions may be the same as those described in the method for producing resin (A).

[0074] When the resin (B1) and / or the resin (B2) are silicone-modified polyester resins, the resin (B1) and the resin (B2) are produced, for example, by reacting the raw material monomer (b1-2) and the raw material monomer (b2-2), respectively. The alcohol component, the carboxylic acid component, and the modified silicone may be reacted together, or the alcohol component and the carboxylic acid component may be reacted and then reacted with the modified silicone, and there is no particular limitation. The esterification catalyst, esterification promoter, and radical polymerization inhibitor used in the reaction may be the same as those described in the method for producing resin (A). The reaction conditions may also be the same as those described in the method for producing resin (A).

[0075] The amount of modified silicone added in resin (B1) and / or resin (B2) is, from the viewpoint of suppressing a decrease in image density, preferably 1 part by mass or more, more preferably 2 parts by mass or more, even more preferably 4 parts by mass or more, and is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and even more preferably 12 parts by mass or less, relative to 100 parts by mass of the total amount of alcohol components and carboxylic acid components in raw material monomer (b1-2) of resin (B1) and / or raw material monomer (b2-2) of resin (B2). The above amounts are calculated based on the alcohol component, the carboxylic acid component and the modified silicone, and do not take into account the amount of water removed by condensation.

[0076] In addition, when the modified silicone has a hydroxy group or a carboxy group, it can also be understood as an alcohol component or a carboxylic acid component, but when the compound having a hydroxy group or a carboxy group contains a silicone skeleton, it is considered to be a modified silicone. For example, when calculating the total amount of the alcohol component and the carboxylic acid component, the modified silicone having a hydroxy group or a carboxy group is not included in these total amounts.

[0077] (Physical properties of resin (B))

[0078] From the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion, the softening point of the resin (B1) is preferably 70°C or higher, more preferably 80°C or higher, even more preferably 85°C or higher, and is preferably 130°C or lower, more preferably 120°C or lower, even more preferably 110°C or lower. From the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion, the softening point of the resin (B2) is preferably 80°C or higher, more preferably 95°C or higher, even more preferably 110°C or higher, and is preferably 170°C or lower, more preferably 160°C or lower, even more preferably 150°C or lower. From the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion, the glass transition temperatures of resin (B1) and resin (B2) are preferably 40° C. or higher, more preferably 45° C. or higher, even more preferably 50° C. or higher, and are preferably 80° C. or lower, more preferably 70° C. or lower, even more preferably 60° C. or lower.

[0079] From the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion, the difference in softening point between resin (B1) and resin (B2) is preferably 10°C or more, more preferably 20°C or more, even more preferably 30°C or more, and is preferably 80°C or less, more preferably 60°C or less, even more preferably 50°C or less.

[0080] The softening points and glass transition temperatures of resin (B1) and resin (B2) can be appropriately adjusted by the type and amount of raw material monomer (b) used, as well as production conditions such as reaction temperature, reaction time, cooling rate, etc., and are determined by the method described in the Examples below. When two or more types of resin (B1) and / or resin (B2) are used in combination, it is preferable that the softening points and glass transition temperatures of resin (B1) and / or resin (B2) obtained as a mixture thereof are within the above-mentioned ranges.

[0081] From the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion, the mass ratio of resin (A) to resin (B) (resin (A) / resin (B)) is preferably 1 / 99 or more, more preferably 3 / 97 or more, even more preferably 4 / 96 or more, and is preferably 25 / 75 or less, more preferably 20 / 80 or less, even more preferably 15 / 85 or less.

[0082] The toner binder resin composition of the present invention may further contain other resins such as crystalline polyester resins and non-crystalline polyester resins in addition to the resin (A) and the resin (B) within a range that does not impair the effects of the present invention. The crystalline polyester resin may be a crystalline polyester resin other than the resin (A). The non-crystalline polyester resin may be a composite resin containing a polyester resin segment and an addition polymerization resin segment. In the binder resin composition for toner of the present invention, from the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion in the binder resin composition for toner, the total content of the resin (A) and the resin (B) is preferably 90% by mass or more, more preferably 95% by mass or more, and is preferably 100% by mass or less, more preferably 100% by mass, from the viewpoint of obtaining an excellent image density even with a small amount of toner adhesion in the binder resin composition for toner.

[0083] [Toner for developing electrostatic images] The toner for developing electrostatic images according to one embodiment of the present invention (hereinafter, also simply referred to as "toner") is a toner for developing electrostatic images containing a binder resin, and the binder resin contains the above-mentioned binder resin composition for toner of the present invention. According to the present invention, it is possible to provide a toner for developing electrostatic images which has excellent image density even when the amount of adhesion is low. The toner for developing electrostatic images contains at least the above-mentioned binder resin and colorant, and may further contain other components such as a release agent, a charge control agent, etc. The toner for developing electrostatic images preferably contains toner base particles (hereinafter also referred to as "toner particles") and an external additive externally added to the toner base particles.

[0084] <Coloring agent> As the colorant, any of the dyes, pigments, etc. used as colorants for toners can be used, such as carbon black, phthalocyanine blue, permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, disazo yellow, etc. can be used, and the toner of the present invention may be either a black toner or another color toner.

[0085] From the viewpoint of improving the image density of the toner, the content of the colorant is preferably 0.3 parts by mass or more, more preferably 1 part by mass or more, and is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, relative to 100 parts by mass of the total amount of the binder resin. In addition, from the viewpoint of improving the image density of the toner, the content of the colorant is preferably 0.3% by mass or more, more preferably 1% by mass or more, and is preferably 20% by mass or less, more preferably 10% by mass or less, based on the toner particles.

[0086] <Release agent> Examples of the release agent include hydrocarbon wax, ester wax, silicone wax, and fatty acid amide wax.

[0087] 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 150° C. or lower, and further preferably 140° C. or lower. When two or more types of release agents are used in combination, it is preferable that the melting points of the respective release agents are within the above-mentioned range.

[0088] The content of the release agent is preferably 0.5 parts by mass or more, more preferably 1.0 parts by mass or more, even more preferably 1.5 parts by mass or more, and is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, even more preferably 3 parts by mass or less, relative to 100 parts by mass of the total amount of the binder resin.

[0089] <Charge control agent> The charge control agent may contain either a positively chargeable charge control agent or a negatively chargeable charge control agent. Examples of the positively charged charge control agent include nigrosine dyes such as "Nigrosine Base EX", "Oil Black BS", "Oil Black SO", "Bontron N-01", "Bontron N-04", "Bontron N-07", "Bontron N-09", "Bontron N-11", and "Bontron N-79" (all manufactured by Orient Chemical Industry Co., Ltd.); triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salt compounds such as "Bontron P-51" (manufactured by Orient Chemical Industry Co., Ltd.), cetyltrimethylammonium bromide, "COPY CHARGE PX VP435" (manufactured by Clariant); polyamine resins such as "AFP-B" (manufactured by Orient Chemical Industry Co., Ltd.); imidazole derivatives such as "PLZ-2001" and "PLZ-8001" (manufactured by Shikoku Chemical Industry Co., Ltd.); and styrene-acrylic resins such as "FCA-701PT" (manufactured by Fujikura Chemical Industry Co., Ltd.).

[0090] Examples of negatively chargeable charge control agents include metal-containing azo dyes such as "Varifast Black 3804", "Bontron S-31", "Bontron S-32", "Bontron S-34", and "Bontron S-36" (all manufactured by Orient Chemical Industry Co., Ltd.), "Aizen Spiron Black TRH", and "T-77" (manufactured by Hodogaya Chemical Industry Co., Ltd.); metal compounds of benzilic acid compounds such as "LR-147" and "LR-297" (both manufactured by Nippon Carlit Co., Ltd.); metal compounds of salicylic acid compounds such as "Bontron E-81", "Bontron E-84", "Bontron E-88", and "Bontron E-304" (all manufactured by Orient Chemical Industry Co., Ltd.), and "TN-105" (manufactured by Hodogaya Chemical Industry Co., Ltd.); copper phthalocyanine dyes; quaternary ammonium salts such as "COPY CHARGE NX VP434" (manufactured by Clariant), nitroimidazole derivatives, and organometallic compounds. The charge control agent to be used may be appropriately selected depending on the characteristics of the printer in which the toner is used, the type of colorant, and the like.

[0091] The content of the charge control agent is preferably 0.01 parts by mass or more, more preferably 0.2 parts by mass or more, even more preferably 0.5 parts by mass or more, and is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, even more preferably 3 parts by mass or less, relative to 100 parts by mass of the total amount of the binder resin.

[0092] [Toner manufacturing method] The toner may be obtained by any known method such as a melt-kneading method, an emulsion phase inversion method, a polymerization method, or an emulsion aggregation method. From the viewpoint of productivity, however, a pulverized toner obtained by a melt-kneading method is preferred. In the case of a pulverized toner by a melt kneading method, for example, raw materials such as resin (A) and resin (B), a colorant, and, if necessary, a release agent and a charge control agent are uniformly mixed in a mixer such as a Henschel mixer, and then melt-kneaded in an internal kneader, a single-screw or twin-screw extruder, an open roll kneader, or the like, and then cooled, pulverized, and classified to produce the toner. The toner production method preferably includes a step of melt-kneading a mixture containing resin (A), resin (B), a colorant, etc. at a temperature in the range of 80° C. or more and 200° C. or less. The melt-kneading temperature is preferably 80° C. or more, more preferably 90° C. or more, and preferably 200° C. or less, more preferably 180° C. or less. The toner production method preferably includes a step of pulverizing and classifying the mixture obtained by melt kneading to obtain toner particles. The pulverization and classification can be performed by a known method.

[0093] The volume median particle size of toner particles (D 50 From the viewpoint of obtaining a toner for developing electrostatic images having excellent image density even with a low adhesion amount, the average particle diameter is preferably 2 μm or more, more preferably 3 μm or more, and even more preferably 4 μm or more, and from the viewpoint of hot offset resistance, the average particle diameter is 8 μm or less, preferably 7 μm or less, and more preferably 6.8 μm or less.

[0094] The toner is preferably treated by adding a fluidizing agent or the like as an external additive to the surface of the toner particles. Examples of the external additive include inorganic material particles such as hydrophobic silica, titanium oxide particles, alumina particles, cerium oxide particles, and carbon black, and polymer particles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic silica is preferred. When an external additive is used, the amount of the external additive added is preferably 0.5 parts by mass or more and preferably 5 parts by mass or less, more preferably 4 parts by mass or less, and even more preferably 3 parts by mass or less, based on 100 parts by mass of the toner particles.

[0095] Toners are used, for example, to develop latent images formed in electrophotography, electrostatic recording, electrostatic printing, etc. Toners can be used as one-component developers, or mixed with a carrier to form two-component developers. EXAMPLES

[0096] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Physical properties of resins and the like were measured by the following methods. In the notation "alkylene oxide (X)" and the like, the number X in parentheses means the average number of moles of alkylene oxide added.

[0097] [Measurement method] [Melting point of crystalline resin] Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample was weighed into an aluminum pan, cooled from room temperature to -10°C at a rate of 10°C / min, and held at that temperature for 1 minute. The sample was then heated to 200°C at a rate of 10°C / min, and cooled from that temperature to -30°C at a rate of 10°C / min. The sample was then heated at a rate of 10°C / min, and the highest endothermic peak temperature observed was taken as the melting point.

[0098] [Softening point of resin] Using a flow tester "CFT-500D" (Shimadzu Corporation), 1 g of sample was heated at a temperature increase rate of 6°C / min, while applying a load of 1.96 MPa with the plunger, and extruding the sample from a nozzle with a diameter of 1 mm and a length of 1 mm. The plunger descent amount of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was taken as the softening point.

[0099] [Glass transition temperature of amorphous resin] Using a differential scanning calorimeter "Q-20" (manufactured by TA Instruments Japan Co., Ltd.), 0.01 to 0.02 g of sample was weighed into an aluminum pan, heated to 200°C, and cooled to 0°C at a rate of 10°C / min. The sample was then heated at a rate of 10°C / min, and the glass transition temperature was determined as the temperature at the intersection of the extension of the baseline below the highest endothermic peak temperature and the tangent line showing the maximum slope from the rising part of the peak to the top of the peak.

[0100] [Acid value and hydroxyl value of resin] The acid value and hydroxyl value of the resin were measured according to the method of JIS K0070: 1992. However, the measurement solvent was changed from the mixed solvent of ethanol and ether specified in JIS K0070: 1992 to a mixed solvent of acetone and toluene [acetone:toluene = 1:1 (volume ratio)] for amorphous resins, and to chloroform for crystalline resins. [Weight average molecular weight of resin] The molecular weight distribution was measured by gel permeation chromatography (GPC) as follows, and the weight average molecular weight was determined. (1) Preparation of sample solution The sample was dissolved in tetrahydrofuran (in the case of amorphous resin) or chloroform (in the case of crystalline resin) at 25° C. so as to have a concentration of 0.5 g / 100 mL. Next, this solution was filtered using a fluororesin filter "DISMIC-25JP" (manufactured by ADVANTEC) with a pore size of 0.2 μm to remove insoluble matter, and a sample solution was obtained. (2) Molecular weight measurement The following measuring equipment and analytical column were used, and tetrahydrofuran (amorphous resin) or chloroform (crystalline resin) was passed as the eluent at a flow rate of 1 mL per minute. The column was stabilized in a thermostatic bath at 40°C. 100 μL of the sample solution was injected into the column for measurement. The molecular weight of the sample was calculated based on a calibration curve that had been prepared in advance. The calibration curve used here included several types of monodisperse polystyrene "A-500" (5.0 × 10 2 ), "A-1000" (1.01 x 10 3 ), "A-2500" (2.63×10 3 ), "A-5000" (5.97 x 10 3 ), "F-1" (1.02 x 10 3 ), "F-2" (1.81 x 10 4 ), "F-4" (3.97 x 10 4 ), "F-10" (9.64×10 4 ), "F-20" (1.90×10 5 ), "F-40" (4.27×10 5 ), "F-80" (7.06×10 5 ), "F-128" (1.09×10 6 ) (all manufactured by Tosoh Corporation) were used as standard samples. Measuring device: "HLC-8220CPC" (Tosoh Corporation) Analytical column: "GMHXL" + "G3000HXL" (manufactured by Tosoh Corporation)

[0101] [Kinematic Viscosity of Modified Silicone] The kinetic viscosity of the modified silicone was determined using the catalog value for each product.

[0102] [Volume median particle size of toner particles (D 50 )〕 The volume median particle size of toner particles (D 50 ) was measured as follows. Measurement device: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.) Aperture diameter: 50μm Analysis software: "Coulter Multisizer (registered trademark) III version 3.51" (Beckman Coulter, Inc.) Electrolyte: "Isoton (registered trademark) II" (manufactured by Beckman Coulter, Inc.) Dispersion: "EMULGEN (registered trademark) 109P" (polyoxyethylene lauryl ether, manufactured by Kao Corporation, HLB (hydrophile-lipophile balance, Griffin method) = 13.6) was dissolved in the electrolyte to obtain a dispersion with a concentration of 5% by mass. Dispersion conditions: 10 mg of the measurement sample was added to 5 mL of the dispersion liquid, and dispersed for 1 minute using an ultrasonic disperser. Then, 25 mL of the electrolyte was added, and the mixture was further dispersed for 1 minute using an ultrasonic disperser to prepare a sample dispersion liquid. Measurement conditions: In a beaker, the sample dispersion is added to 100 mL of the electrolyte to adjust the concentration so that the particle diameters of 30,000 particles can be measured in 20 seconds. Then, 30,000 particles are measured, and the volume median particle diameter (D 50 ) was sought.

[0103] [Toner Evaluation] [Image Density] Using a commercially available printer, Microline (registered trademark) 5400 (Oki Data Corporation), on high-quality paper, "J paper A4 size" (Fujifilm Business Innovation Co., Ltd.), the amount of toner attached to the paper was 0.25 to 0.30 mg / cm 2 A solid image was output, and a print was obtained. Next, the temperature of the fixing unit was set to 150° C., and the toner was fixed in the portrait direction on A4 sheets at a speed of 1.5 seconds per sheet to obtain a printed matter. The reflected image density of the fixed image portion of the output print was measured using a colorimeter "SpectroEye" (GretagMacbeth, light irradiation conditions: standard light source D50, observation field of view 2°, density standard DINNB, absolute white standard). The higher the reflected image density value, the better the image density.

[0104] [Resin manufacturing] [Production of crystalline polyester (A)] Production Example A1 (Crystalline Polyester Resin A1) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 1,623g of ethylene glycol, 4,817g of dodecanedioic acid, and 3,560g of behenic acid were added, and the mixture was heated to 140°C under a nitrogen atmosphere while stirring, and held for 1 hour. The mixture was then heated at a rate of 10°C / h, and after reaching 200°C, 30g of di(2-ethylhexanoate)tin(II) was added and held for 1 hour. After holding, the pressure in the flask was reduced, and the reaction was continued at 8kPa until the desired softening point, to obtain crystalline polyester resin A1. The physical properties are shown in Table 1.

[0105] Production Examples A2 to A4, Comparative Production Example A1 (Crystalline Polyester Resins A2 to A5) Crystalline Resins A2 to A5 were obtained in the same manner as in Production Example A1, except that the raw material monomer (a) was changed as shown in Table 1. The physical properties are shown in Table 1.

[0106] [Table 1]

[0107] [Production of amorphous polyester (B)] Production Example B1 (Amorphous Polyester Resin B1-1) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3,721g of propylene oxide (2.2) adduct of bisphenol A, 3,455g of ethylene oxide (2.2) adduct of bisphenol A, 2,824g of terephthalic acid, and 50g of tin (II) di(2-ethylhexanoate) were added, and the mixture was heated to 235°C under a nitrogen atmosphere while stirring. After maintaining the temperature at 235°C for 6 hours, the pressure in the flask was reduced, and the reaction was continued at 8kPa until the desired softening point, to obtain amorphous polyester resin B1-1. The physical properties are shown in Table 2.

[0108] Production Example B2 (Silicone Modified Amorphous Polyester Resin B1-2) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 3,535g of propylene oxide (2.2) adduct of bisphenol A, 3,283g of ethylene oxide (2.2) adduct of bisphenol A, 2,683g of terephthalic acid, 469g of modified silicone "KF-864" (manufactured by Shin-Etsu Chemical Co., Ltd.), and 48g of tin (II) di(2-ethylhexanoate) were added, and the mixture was heated to 235°C while stirring under a nitrogen atmosphere, and then kept at 235°C for 6 hours. The pressure in the flask was then reduced, and the reaction was continued at 8kPa until the desired softening point, to obtain silicone-modified amorphous polyester resin B1-2. The physical properties are shown in Table 2.

[0109] Manufacturing Examples B3 to B5 (Silicone Modified Amorphous Polyester Resins B1-3 to B1-5) Silicone-modified amorphous polyester resins B1-3 to B1-5 were obtained in the same manner as in Production Example B2, except that the raw material monomer (b) was changed as shown in Table 2. The physical properties are shown in Table 2.

[0110] Production Example B6 (Amorphous Polyester Resin B2-1) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 4,928g of propylene oxide (2.2) adduct of bisphenol A, 1,961g of ethylene oxide (2.2) adduct of bisphenol A, 1,502g of terephthalic acid, 1,030g of dodecenyl succinic anhydride (DDSA-C), and 50g of di(2-ethylhexanoate) tin (II) were added, and the mixture was heated to 235°C under a nitrogen atmosphere while stirring. After maintaining the mixture at 235°C for 6 hours, the pressure in the flask was reduced and the mixture was reacted at 8kPa for 1 hour. The mixture was then cooled to 220°C, 579g of trimellitic anhydride was added, and the mixture was reacted for 1 hour. The crosslinking reaction was then carried out at 8kPa until the specified softening point was reached, and amorphous polyester resin B2-1 was obtained. The physical properties are shown in Table 2.

[0111] Production Example B7 (Silicone Modified Amorphous Polyester Resin B2-2) The inside of a 10L four-neck flask equipped with a nitrogen inlet tube, a dehydration tube, a stirrer, and a thermocouple was replaced with nitrogen, and 4,435g of propylene oxide (2.2) adduct of bisphenol A, 1,765g of ethylene oxide (2.2) adduct of bisphenol A, 1,352g of terephthalic acid, 927g of DDSA-C, 949g of modified silicone "KF-864" (manufactured by Shin-Etsu Chemical Co., Ltd.), and 45g of di(2-ethylhexanoate) tin (II) were added, and the mixture was heated to 235°C while stirring under a nitrogen atmosphere, and then kept at 235°C for 6 hours. The pressure in the flask was then reduced, and the mixture was reacted at 8kPa for 1 hour. The mixture was then cooled to 220°C, 521g of trimellitic anhydride was added, and the mixture was reacted for 1 hour. The crosslinking reaction was then carried out at 8kPa until the specified softening point was reached, and silicone-modified amorphous polyester resin B2-2 was obtained. The physical properties are shown in Table 2.

[0112] [Table 2]

[0113] The modified silicones used in Production Examples B2 to B5 and B7 are as follows. KF-864: Modified silicone "KF-864" (silicone with monoamino group on the side chain, kinematic viscosity (25℃) = 1,700mm 2 / s, functional group equivalent weight = 3,800g / mol, Shin-Etsu Chemical Co., Ltd.) KF-865: Modified silicone "KF-865" (silicone with monoamino group on the side chain, kinematic viscosity (25℃) = 110mm 2 / s, functional group equivalent weight = 5,000g / mol, Shin-Etsu Chemical Co., Ltd.) X-22-4015: Modified silicone oil "X-22-4015" (silicone with carbinol group (hydroxyl group) on the side chain, kinematic viscosity (25℃) = 130mm 2 / s, functional group equivalent 30g / mol, Shin-Etsu Chemical Co., Ltd.) KF-8008: Modified silicone oil "KF-8008" (silicone with amino groups at both ends, kinematic viscosity (25℃) = 450mm 2 / s, functional group equivalent weight = 5,700g / mol, Shin-Etsu Chemical Co., Ltd.)

[0114] [Toner manufacturing] Example 1 100 parts by mass of binder resin consisting of resin (A), resin (B1), and resin (B2) in the amounts shown in Table 3, 2.0 parts by mass of positive charge control agent "Bontron N-79" (manufactured by Orient Chemical Industry Co., Ltd.), and 6.0 parts by mass of colorant "Regal 330R" (manufactured by Cabot Corporation, carbon black) were added, and the mixture was thoroughly premixed in a Henschel mixer, and then melt-kneaded using a co-rotating twin-screw extruder at a roll rotation speed of 200 r / min (circumferential speed of 0.3 m / min) and a heating temperature of 100° C. inside the roll. The resulting melt-kneaded product was cooled and coarsely pulverized, and then melt-kneaded using a co-rotating twin-screw extruder with a kneading section having a total length of 1,560 mm, a screw diameter of 42 mm, and a barrel inner diameter of 43 mm. The screw rotation speed was 200 r / min (circumferential speed 0.3 m / min), the heating temperature inside the roll was set to 100° C., the temperature of the kneaded material was 160° C., the supply rate of the kneaded material was 10 kg / h, and the average residence time was approximately 18 seconds.

[0115] After cooling the kneaded product, it was coarsely pulverized to about 1 mm using a hammer mill (manufactured by Hosokawa Micron Corporation). The obtained coarsely pulverized product was finely pulverized in a collision plate type jet mill pulverizer IDS-2 (manufactured by Japan Pneumatic Co., Ltd.) at a feed rate of 4.0 kg / h to obtain the desired volume median particle size (D 50 ) was set to 6.5 μm, and the grinding pressure was adjusted to obtain toner particles.

[0116] To 100 parts by mass of the obtained toner particles, 1.0 part by mass of hydrophobic silica "NAX-50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobic treatment agent: HMDS, average particle size: 30 nm) was added, and mixed in a Henschel mixer to obtain a toner. The image density was evaluated by the method described in [Toner Evaluation] above. The evaluation results are shown in Table 3.

[0117] Examples 2 to 8 and Comparative Examples 1 to 2 Toners of Examples 2 to 8 and Comparative Examples 1 and 2 were obtained in the same manner as in Example 1, except that the resin (A), resin (B1), and resin (B2) were changed to the resins and contents shown in Table 3. The evaluation results are shown in Table 3.

[0118] [Table 3]

[0119] As shown in Table 3, from the results of the Examples and Comparative Examples, the toner containing the binder resin composition for a toner exhibited high image density with a low adhesion amount. On the other hand, the toner of Comparative Example 1, in which Resin A5, a polycondensate of an aliphatic diol and an aliphatic dicarboxylic acid, was used instead of Resin (A), and the toner of Comparative Example 2, in which neither Resin (B1) nor Resin (B2) was a silicone-modified resin, showed low image density due to whitening of the image surface. In addition, the results of Examples 1, 8, and 4 show that the image density increases when the weight average molecular weight of the resin (A) is low. Furthermore, the results of Examples 1, 5, and 7, and 6 show that the image density increases when the modified silicone is an amino-modified silicone.

Claims

1. A toner binder resin composition containing a crystalline polyester resin (A) and an amorphous polyester resin (B), wherein the crystalline polyester resin (A) is a polycondensate of a raw material monomer (a) containing an aliphatic diol, an aliphatic dicarboxylic acid, and at least one selected from the group consisting of an aliphatic monoalcohol having 10 to 22 carbon atoms and an aliphatic monocarboxylic acid having 10 to 22 carbon atoms, the amorphous polyester resin (B) includes a linear polyester resin (B1) and a non-linear polyester resin (B2), and at least one of the linear polyester resin (B1) and the non-linear polyester resin (B2) is a silicone-modified polyester resin which is a reaction product of a raw material monomer (b) containing an alcohol component containing a dihydric or higher alcohol, a carboxylic acid component containing a dihydric or higher carboxylic acid, and at least one selected from the group consisting of a modified silicone having a repeating unit represented by formula (1) and a repeating unit represented by formula (2), and a modified silicone having a repeating unit represented by formula (2) and a structure represented by formula (3). A toner binder resin composition. 【Chemical 1】 [In formula (1), each R is independently a hydrocarbon group having 1 to 6 carbon atoms, each R' is independently an alkylene group having 1 to 10 carbon atoms, a is 1 or 0, X is independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site.] [Chemical Formula 2] [In formula (2), each R is independently a hydrocarbon group having 1 to 6 carbon atoms, and * is a bonding site.] *-SiR ３－ｂ (R''-X) ｂ (3) [In formula (3), each R is independently a hydrocarbon group having 1 to 6 carbon atoms, each R'' is independently an alkylene group having 1 to 10 carbon atoms, b is an integer of 1 to 3, X is independently a group containing an amino group, a carboxy group, an epoxy group, or a hydroxy group, and * is a bonding site.]

2. The toner binder resin composition according to claim 1, wherein the raw material monomer (a) contains the aliphatic monocarboxylic acid, and the content of the aliphatic monocarboxylic acid is 10 mol% or more in the raw material monomer.

3. The toner binder resin composition according to claim 1, wherein the weight average molecular weight of the crystalline polyester (A) is 500 or more and 5,000 or less.

4. The kinematic viscosity of the modified silicone is 90 mm ２ / s or more, and the toner binder resin composition according to claim 1.

5. The toner binder resin composition according to claim 1, wherein the modified silicone has a repeating unit represented by formula (1) and a repeating unit represented by formula (2).

6. The toner binder resin composition according to claim 1, wherein X is a group having an amino group.

7. The toner binder resin composition according to claim 1, wherein the aliphatic monocarboxylic acid and the aliphatic monoalcohol each have 16 or more carbon atoms.

8. The toner binder resin composition according to claim 1, wherein the acid value of the crystalline polyester resin (A) is 5 mgKOH / g or less, and the sum of the acid value and the hydroxyl value is 10 mgKOH / g or less.

9. The toner binder resin composition according to claim 1, wherein the charged amount of the modified silicone in the raw material monomer (b) is 1 part by mass or more and 20 parts by mass or less with respect to 100 parts by mass in total of the alcohol component and the carboxylic acid component.

10. The toner binder resin composition according to claim 1, wherein the mass ratio of the crystalline polyester resin (A) to the amorphous polyester resin (B) (crystalline polyester resin (A) / amorphous polyester resin (B)) is 1 / 99 or more and 25 / 75 or less.

11. An electrostatic charge image developing toner containing the toner binder resin composition according to any one of claims 1 to 10 and a colorant.

12. A method for producing an electrostatic charge image developing toner, comprising a step of melt-kneading the toner binder resin composition according to any one of claims 1 to 10 to obtain a melt-kneaded product, and a step of pulverizing and classifying the melt-kneaded product to obtain toner mother particles.

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