JP7833335B2 - Toner binder resin composition - Google Patents

Description

This invention relates to a toner binder resin composition used for developing latent images formed in electrophotography, electrostatic recording, electrostatic printing, etc., and toner for developing electrostatic images containing the toner binder resin composition.

In the field of electrophotography, the development of electrophotographic systems has necessitated the development of electrostatic image developing toners (hereinafter simply referred to as "toners") that can handle higher image quality and higher speeds. For example, to accommodate the increased speed of machines, toners are required to have excellent low-temperature fixing properties.
However, toners with good low-temperature fixing properties tend to be exposed to high temperatures when large quantities of printed materials are stacked, as they are not cooled properly. This can cause the fixed image to soften, leading to sticking of printed surfaces due to their own weight, and resulting in reduced heat resistance, such as image degradation when peeled off, and unevenness in image density and gloss. Therefore, there is a need for toners that can achieve both low-temperature fixing and heat resistance.

For example, Patent Document 1 describes a toner having toner particles containing a binder resin and a crystalline polyester, for the purpose of providing a toner with excellent low-temperature fixability and image preservation properties, characterized in that the binder resin contains a polyester having a silicone structure.
Furthermore, Patent Document 2 describes a toner binder resin that is a reaction product of an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid compound, and a silicone having at least one selected from an amino group, a carboxyl group, an epoxy group, and a carbinol group in its side chain, with the aim of providing a toner with excellent low-temperature fixability, document offset resistance, and filming resistance.

Japanese Patent Publication No. 2021-060582 Japanese Patent Publication No. 2020-063412

The technology described in Patent Document 1 suffered from insufficient compatibility between the obtained silicone-containing polyester and crystalline polyester during heating, leaving room for improvement in low-temperature fixability. Furthermore, while the technology described in Patent Document 2 provided a toner with excellent low-temperature fixability, document offset resistance, and filming resistance, it still lacked room for improvement in image heat resistance. Therefore, there is a need for the development of a toner with excellent low-temperature fixability and image heat resistance.

This invention relates to a toner binder resin composition that provides a toner with excellent low-temperature fixability and image heat resistance, and to a toner for electrostatic image development containing the toner binder resin composition.

The present invention relates to either [1] or [2] below.
[1] A binder resin composition for toner containing an amorphous resin (A) which is a polycondensate of an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid compound, and a modified silicone having polar groups, and a crystalline resin (C),
A binder resin composition for toner, wherein the solubility parameter (SP value) (SP _A ) of Fedors calculated from the alcohol and carboxylic acid components of the amorphous resin (A) is 11.0 (cal/ ^cm³ ) ^1/2 or less, the polarity value of the modified silicone is 10.0 mg KOH/g or more, and the SP value (SP _C ) of the crystalline resin (C) is 9.6 (cal/ ^cm³ ) ^1/2 or less.
[2] A toner for developing electrostatic images, wherein the binder resin contains the binder resin composition for toner described in [1].

According to the present invention, a toner binder resin composition that provides a toner with excellent low-temperature fixability and image heat resistance, and a toner for electrostatic image development containing the toner binder resin composition are provided.

[Toner binder resin composition]
A toner binder resin composition according to one embodiment of the present invention contains an amorphous resin (A) which is a polycondensate of an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid compound, and a modified silicone having polar groups, and a crystalline resin (C), wherein the Fedors solubility parameter (SP value) (SP _A ) calculated from the alcohol component and carboxylic acid component of the amorphous resin (A) is 11.0 (cal/ ^cm³ ) ^1/2 or less, the polarity value of the modified silicone is 10.0 mgKOH/g or more, and the SP value (SP _C ) of the crystalline resin (C) is 9.6 (cal/ ^cm³ ) ^1/2 or less.
According to the above configuration, it is possible to provide a toner binder resin composition that gives a toner with excellent low-temperature fixability and image heat resistance, and a toner for electrostatic image development containing the toner binder resin composition.

The reason for these effects is not entirely clear, but it can be thought to be as follows.
To improve the low-temperature fixing performance of toner, it is effective to use a crystalline resin with high affinity to amorphous resin to lower the toner fixing temperature. However, if the affinity between amorphous and crystalline resins is too high, the crystalline resin will dissolve too much in the amorphous resin, leading to adverse effects such as a deterioration in heat resistance, including image heat resistance.
In amorphous resin (A), if the Fedors solubility parameter (SP value) calculated from the alcohol and carboxylic acid components of amorphous resin (A) is 11.0 (cal/ ^cm³ ) ^1/2 or less, the reaction between the modified silicone and the carboxylic acid component proceeds preferentially, and then the reaction product of the modified silicone and the carboxylic acid component reacts with the alcohol component, resulting in a high rate of introduction of modified silicone into amorphous resin (A). Furthermore, if the polarity value of the modified silicone is 10.0 mgKOH/g or higher, the modified silicone portion introduced into amorphous resin (A) can interact with crystalline resin (C) via intermolecular forces such as hydrogen bonding through unreacted polar groups, resulting in high compatibility between amorphous resin (A) and crystalline resin (C) even if the SP value of crystalline resin (C) is 9.6 (cal/ ^cm³ ) ^1/2 or less. If the polar group of the modified silicone is an amino group, and the crystalline resin (C) has an acidic group, it is thought that the amorphous resin (A) and the crystalline resin (C) will become even more compatible through acid-base interactions. Therefore, even if the melting point of the crystalline resin (C) is relatively high, the toner can soften at low temperatures, and the low-temperature fixability of the toner is expected to improve. On the other hand, in processes where heat resistance of the image is required, the crystalline resin (C), which has a relatively high melting point, is more likely to crystallize, and hardens the binder resin composition for the toner, thus improving the heat resistance of the fixed image.

The definitions of various terms used in this specification are shown below.
Whether a resin is crystalline or amorphous is determined by its crystallinity index. The crystallinity index is defined as the ratio of the resin's softening point to its 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 in which the crystallinity index is 0.6 or higher and 1.4 or lower. An amorphous resin is one in which no endothermic peak is observed, or if observed, the crystallinity index is less than 0.6 or greater than 1.4. The crystallinity index can be appropriately adjusted depending on the type and ratio of raw material monomers, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate.
In this 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 acid, and alkyl esters of each carboxylic acid (alkyl group having 1 to 3 carbon atoms).
"Volume median particle size (D ₅₀ )" refers to a particle size where the cumulative volume frequency calculated using volume fractions accounts for 50% of the total volume frequency, starting from the smallest particle size.
"Bisphenol A" is 2,2-bis(4-hydroxyphenyl)propane.
Regarding hydrocarbon groups, the notation "(iso or tertiary)" and "(iso)" in parentheses means both the presence and absence of these prefixes, and if these prefixes are absent, it indicates the normal group.
"(Meth)acrylic acid" means at least one selected from acrylic acid and methacrylic acid.

The toner binder resin composition of the present invention contains an amorphous resin (A) which is a polycondensate of an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid compound, and a modified silicone having polar groups, and a crystalline resin (C).

[Amorphous resin (A)]
The amorphous resin (A) (hereinafter also simply referred to as "resin (A)") is a polycondensate of an alcohol component, a carboxylic acid component, and a modified silicone, and includes an amorphous silicone-modified polyester resin having amorphous polyester resin segments and silicone segments.

Furthermore, resin (A) may include not only an amorphous silicone-modified polyester resin, but also an amorphous polyester resin which is a polycondensate of an unreacted alcohol component and a carboxylic acid component with the modified silicone.

<Alcohol content>
The alcohol component includes dihydric or higher alcohols.
The content of dihydric or higher alcohols is preferably 80% by mass or more, more preferably 90% by mass or more, even more preferably 95% by mass or more, and 100% by mass or less, in the alcohol component.
Examples of alcohols with a valency of 2 or higher include alkylene oxide adducts of aromatic diols, linear or branched aliphatic diols, alicyclic diols, and polyhydric alcohols with a valency of 3 or higher. Among these, alkylene oxide adducts of aromatic diols or linear or branched aliphatic diols are preferred, and 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, and more preferably of formula (I):

This is an alkylene oxide adduct of bisphenol A represented by the formula (wherein ^OR1 and ^R2O are oxyalkylene groups, ^R1 and ^R2 are independently ethylene groups or propylene groups, x and y represent the average number of moles of alkylene oxide added, each being 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).
Examples of alkylene oxide adducts of bisphenol A include propylene oxide adducts of bisphenol A and ethylene oxide adducts of bisphenol A. One or more of these may be used. Among these, propylene oxide adducts of bisphenol A and combinations of propylene oxide adducts of bisphenol A and ethylene oxide adducts of bisphenol A are preferred, with propylene oxide adducts of bisphenol A being more preferred.
If the alcohol component contains an alkylene oxide adduct of bisphenol A, the amount thereof is preferably 70 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, and even more preferably 100 mol%.

As for the linear or branched aliphatic diol, aliphatic diols having a hydroxyl group bonded to a secondary carbon atom are preferred.
The aliphatic diol having a hydroxyl group bonded to a secondary carbon atom preferably has 3 to 4 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 using an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom as the alcohol component, the amount is preferably 70 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, and even more preferably 100 mol% of the alcohol component.

Other examples of linear or branched aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-dodecanediol, 1,2-propanediol, and neopentyl glycol.

Examples of alicyclic diols include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane] and alkylene oxide adducts of hydrogenated bisphenol A with 2 to 4 carbon atoms (average number of added moles: 2 to 12).
Examples of polyhydric alcohols with a valency of 3 or higher include glycerin, pentaerythritol, trimethylolpropane, and sorbitol.
These alcohol components may be used individually or in combination of two or more types.

<Carboxylic acid components>
The carboxylic acid component includes divalent or higher carboxylic acid compounds, such as dicarboxylic acids and trivalent or higher polycarboxylic acids.
The content of divalent or greater carboxylic acid compounds is preferably 80 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, in the carboxylic acid component.
Examples of divalent or higher carboxylic acid compounds include aromatic dicarboxylic acid compounds, linear or branched aliphatic dicarboxylic acid compounds, alicyclic dicarboxylic acid compounds, and trivalent or higher polycarboxylic acid compounds. Among these, aromatic dicarboxylic acid compounds are preferred.

Examples of aromatic dicarboxylic acid compounds include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid or terephthalic acid are preferred, and terephthalic acid is more preferred.
The amount of aromatic dicarboxylic acid compound is preferably 80 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, in the carboxylic acid component.

The number of carbon atoms in the linear or branched aliphatic dicarboxylic acid compound is preferably 2 or more, more preferably 4 or more, even more preferably 8 or more, even more preferably 10 or more, and preferably 22 or less, more preferably 16 or less.
Examples of linear or branched aliphatic dicarboxylic acid compounds include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, dodecanediic acid, tetradecanediic acid, succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms, or their anhydrides or alkyl esters having 1 to 3 carbon atoms. Examples of succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include dodecyl succinic acid, dodecenyl succinic acid, and octenyl succinic acid. Among these, fumaric acid is preferred.
If a linear or branched aliphatic dicarboxylic acid compound is included, its amount is preferably 10 mol% or more, more preferably 20 mol% or more, even more preferably 30 mol% or more, and preferably 90 mol% or less, more preferably 80 mol% or less, of the carboxylic acid component.

The polycarboxylic acid compounds with a valency of 3 or higher are preferably trivalent carboxylic acids, such as trimellitic acid or its anhydride. Among these, trimellitic acid or its anhydride is preferred.
When a polycarboxylic acid compound with a valency of three or more is included, the amount of the polycarboxylic acid compound with a valency of three or more is preferably 1 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, and preferably 35 mol% or less, more preferably 25 mol% or less, and even more preferably 20 mol% or less, in the carboxylic acid component.
These carboxylic acid compounds may be used individually or in combination of two or more.

The ratio of carboxyl groups of the carboxylic acid component to hydroxyl groups of the alcohol component (COOH group/OH group) is preferably 0.6 or higher, more preferably 0.7 or higher, and preferably 1.1 or lower, more preferably 1.0 or lower.

<Modified Silicone>
The modified silicone used in resin (A) is, from the viewpoint of obtaining a toner binder resin composition that provides a toner with excellent low-temperature fixability and image heat resistance, a modified silicone having a polar group reactive with a hydroxyl group or a carboxyl group in its side chain, preferably a modified silicone having a polar group reactive with a hydroxyl group or a carboxyl group in its side chain, and more preferably a modified silicone having at least one polar group selected from an amino group, a carboxyl group, an epoxy group, and a hydroxyl group in its side chain.

From the viewpoint of obtaining a toner binder resin composition that provides a toner with excellent low-temperature fixability and image heat resistance, the polarity value of the modified silicone is 10.0 mg KOH/g or more, preferably 10.5 mg KOH/g or more, more preferably 11.0 mg KOH/g or more, and preferably 50.0 mg KOH/g or less, more preferably 40.0 mg KOH/g or less, and even more preferably 30.0 mg KOH/g or less.
The polarity value of modified silicone is the value obtained by converting the polar groups present in 1 g of modified silicone into the number of mg of potassium hydroxide. For example, if the polar group is an amino group, the polarity value can be measured by the method of JIS K2501:2003, and if the polar group is a carboxyl group or a hydroxyl group, it can be measured by the method of JIS K0070:1992. If the polar group is an epoxy group, the polarity value can be determined by adding hydrochloric acid to a solution of modified silicone containing epoxy groups and converting the amount consumed by chlorohydrination into the number of mg of potassium hydroxide.

The modified silicone preferably has repeating units represented by formula (1) and/or a structure represented by formula (3), and repeating units represented by formula (2). More preferably, it is a modified silicone having repeating units represented by formula (1) and repeating units represented by formula (2), and a modified silicone having repeating units represented by formula (2) and structures represented by formula (3) at both ends, and even more preferably, a modified silicone having repeating units represented by formula (1) and repeating units represented by formula (2).

[In formula (1), R is independently a hydrocarbon group having 1 to 6 carbon atoms, 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 carboxyl group, an epoxy group, or a hydroxyl group, and * is a bonding site.]

[In formula (2), 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 independently a hydrocarbon group having 1 to 6 carbon atoms, R'' is independently an alkylene group having 1 to 10 carbon atoms, b is an integer from 1 to 3, X is independently a group containing an amino group, a carboxyl group, an epoxy group, or a hydroxyl group, and * is a bonding site with the repeating unit represented by formula (2).]

Furthermore, the repeating units represented by equation (1) and equation (2) may be random or block-based, and are not particularly limited.

In formulas (1) to (3), the number of carbon atoms in the hydrocarbon group R is 6 or less, preferably 4 or less, more preferably 3 or less, even more preferably 2 or less, and even more preferably 1.
Examples of hydrocarbon groups for R include methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, pentyl, and phenyl groups. Among these, the methyl group is preferred.

In formulas (1) and (3), the number of carbon atoms in the alkylene groups R' and R'' is 10 or less, preferably 8 or less, more preferably 5 or less, even more preferably 4 or less, even more preferably 3 or less, and preferably 1 or more.
Examples of alkylene groups for R' and R'' include methanediyl group, ethane-1,2-diyl group, ethane-1,1-diyl group, n-propane-1,3-diyl group, n-propane-1,2-diyl group, 2-methylethane-1,2-diyl group, 1,4-n-butyl group, 1,2-tert-butyl group, and 1,5-pentyl group. Among these, methanediyl group, ethane-1,2-diyl group, n-propane-1,3-diyl group, and n-propane-1,2-diyl group are preferred.

X is, independently, a group containing an amino group, a carboxyl group, an epoxy group, or a hydroxyl group, and is preferably an amino group, a hydroxyl group, a hydroxyalkyloxy group, a carboxyl group, a carboxyalkyloxy group, an epoxy group, a glycidyl group, a glycidyloxy group, or an alicyclic epoxy group. A hydroxyalkyloxy group may have multiple hydroxyl groups, and a carboxyalkyloxy group may have multiple carboxyl groups. Among these, X is preferably an amino group from the viewpoint of reactivity with the carboxyl group of a divalent or higher carboxylic acid compound, and from the viewpoint of improving the low-temperature fixability of the toner.

The modified silicone contains 40 or fewer repeating units represented by formula (1), preferably 20 or fewer, more preferably 10 or fewer, and 1 or more.
Furthermore, the repeating unit represented by formula (2) contains 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.

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, and even more preferably 6,000 g/mol or less.
Note that functional group equivalent refers to the mass of modified silicone per mole of functional group.

The kinematic viscosity of the modified silicone is preferably 10 ^mm² /s or more, more preferably 30 ^mm² /s or more, even more preferably 50 ^mm² /s or more, and preferably 4,000 ^mm² /s or less, more preferably 3,000 ^mm² /s or less, and even more preferably 2,000 ^mm² /s or less at 25°C.
The kinematic viscosity of modified silicone can be measured, for example, using a fully automated micro-kinematic viscometer (manufactured by Viscotec Co., Ltd.).

Examples of the modified silicones mentioned above include: modified silicones having amino groups in the side chain (commercial products such as "KF-864" and "KF-865" manufactured by Shin-Etsu Chemical Co., Ltd.), modified silicones having amino groups at both ends (commercial products such as "KF-8012" manufactured by Shin-Etsu Chemical Co., Ltd.), modified silicones having an amino group at one end; modified silicones having carboxyl groups in the side chain (commercial products such as "X-22-3701E" manufactured by Shin-Etsu Chemical Co., Ltd. and "BY16-880" manufactured by Toray Dow Corning Co., Ltd.), modified silicones having carboxyl groups at both ends (commercial products such as "X-22-162C" manufactured by Shin-Etsu Chemical Co., Ltd.), modified silicones having a carboxyl group at one end (commercial products such as "X-22-3710" manufactured by Shin-Etsu Chemical Co., Ltd.); epoxy groups Examples include modified silicones having a side chain (e.g., "X-22-343" (manufactured by Shin-Etsu Chemical Co., Ltd.)), modified silicones having epoxy groups at both ends (e.g., "X-22-163B" and "X-22-169B" (manufactured by Shin-Etsu Chemical Co., Ltd.)), modified silicones having an epoxy group at one end (e.g., "X-22-173BX" (manufactured by Shin-Etsu Chemical Co., Ltd.)); modified silicones having a hydroxyl group in the side chain (e.g., "X-22-4039" (manufactured by Shin-Etsu Chemical Co., Ltd.)), modified silicones having hydroxyl groups at both ends (e.g., "KF-6003" and "KF-6002" (manufactured by Shin-Etsu Chemical Co., Ltd.)), and modified silicones having a hydroxyl group at one end (e.g., "X-22-170BX" and "X-22-170DX" (manufactured by Shin-Etsu Chemical Co., Ltd.)).

When the modified silicone is a modified silicone having a group containing an amino group, examples of the groups represented by *-(R') _a -X and -(R''-X) in the repeating unit represented by formula (1) and the structure represented by formula (3) include the following substituents 1a-1 to 1a-3.

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

When the modified silicone is a modified silicone having a group containing an epoxy group, it is preferable that X and Y in the repeating unit represented by formula (1) and the structure represented by formula (3) are a glycidyl group, a glycidyloxy group, and an alicyclic epoxy group, and examples of the groups represented by *-(R') _a -X and -(R''-X) include the substituents 1b-4 to 1b-6 listed below. Among these, substituent 1b-4 is preferred.

When the modified silicone is a modified silicone having a group containing a carboxyl group, it is preferable that X and Y in the repeating unit represented by formula (1) and the structure represented by formula (3) are a carboxyl group or a carboxyalkyloxy group, and examples of the groups represented by *-(R') _a -X and -(R''-X) include the following substituents 1b-7.

(Method for manufacturing resin (A))
Resin (A) is produced, for example, by polycondensation of an alcohol component, a carboxylic acid component, and a modified silicone. The alcohol component, carboxylic acid component, and modified silicone may be reacted together, or the alcohol component and carboxylic acid component may be reacted first, followed by the modified silicone; the method is not particularly limited.
In this reaction, if necessary, an esterification catalyst such as di(2-ethylhexanoate)tin(II), dibutyltin oxide, or titanium diisopropylate bistriethanolamine may be used in an amount of 0.01 parts by mass to 5 parts by mass per 100 parts by mass of the total amount of the alcohol component and carboxylic acid component; and an esterification co-catalyst such as gallic acid (same as 3,4,5-trihydroxybenzoic acid) may be used in an amount of 0.001 parts by mass to 0.5 parts by mass per 100 parts by mass of the total amount of the alcohol component and carboxylic acid component.
Furthermore, when using monomers having unsaturated bonds, such as fumaric acid, in polycondensation, a radical polymerization inhibitor may be used, preferably in an amount of 0.001 parts by mass or more and 0.5 parts by mass or less, per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. An example of a 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 preferably 250°C or lower, more preferably 240°C or lower.
The reaction may also be carried out in an inert gas atmosphere.

The amount of modified silicone added to resin (A) is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 1 part by mass or more, and preferably 9 parts by mass or less, more preferably 7 parts by mass or less, even more preferably 6 parts by mass or less, even more preferably 5 parts by mass or less, and even more preferably 4 parts by mass or less, relative to 100 parts by mass of the theoretical yield of polyester obtained from the alcohol and carboxylic acid components in the raw materials of resin (A).
If resin (A) contains an amorphous silicone-modified polyester resin which is a polycondensate of an alcohol component, a carboxylic acid component, and a modified silicone, then the amorphous polyester resin consisting of the same alcohol component and carboxylic acid component as the amorphous silicone-modified polyester resin shall be considered as resin (A).

Furthermore, if a modified silicone contains a hydroxyl group or carboxyl group, it may be understood as an alcohol component or a carboxylic acid component. However, if the compound containing the hydroxyl group or carboxyl group includes a silicone skeleton, it is considered a modified silicone. For example, when calculating the total amount of alcohol and carboxylic acid components, the modified silicone containing the hydroxyl group or carboxyl group is not included in the total amount.

(Physical properties of resin (A))
The solubility parameter (SP value) (SP _A ) calculated by the Fedors method from the alcohol and carboxylic acid components of resin (A) is 11.0 (cal/ ^cm³ ) ^1/2 or less, from the viewpoint of obtaining a toner binder resin composition that provides a toner with excellent low-temperature fixability and image heat resistance. Preferably, it is 9.8 (cal/ ^cm³ ) ^1/2 or more, more preferably 10.0 (cal/ ^cm³ ) ^1/2 or more, and even more preferably 10.2 (cal/ ^cm³ ) ^1/2 or more.

The acid value of resin (A) is preferably 0.1 mg KOH/g or more, more preferably 0.5 mg KOH/g or more, even more preferably 1 mg KOH/g or more, and preferably 40 mg KOH/g or less, more preferably 30 mg KOH/g or less, even more preferably 20 mg KOH/g or less, and even more preferably 17 mg KOH/g or less.
The hydroxyl value of resin (A) is preferably 0.1 mg KOH/g or more, more preferably 10 mg KOH/g or more, even more preferably 20 mg KOH/g or more, and preferably 90 mg KOH/g or less, more preferably 80 mg KOH/g or less, and even more preferably 70 mg KOH/g or less.

The softening point of resin (A) is preferably 70°C or higher, more preferably 80°C or higher, and even more preferably 85°C or higher. Furthermore, from the viewpoint of further improving low-temperature fixability, it is preferably 130°C or lower, more preferably 120°C or lower, and even more preferably 110°C or lower.
The glass transition temperature of resin (A) is preferably 40°C or higher, more preferably 45°C or higher, and even more preferably 48°C or higher. Furthermore, from the viewpoint of further improving low-temperature fixability, it is preferably 80°C or lower, more preferably 70°C or lower, and even more preferably 65°C or lower.

The number-average molecular weight (Mn) of resin (A) is preferably 500 or more, more preferably 1,000 or more, even more preferably 1,200 or more, and preferably 20,000 or less, more preferably 10,000 or less, even more preferably 7,000 or less, even more preferably 5,000 or less, and even more preferably 3,000 or less.
The weight-average molecular weight (Mw) of resin (A) is preferably 500 or more, more preferably 1,000 or more, even more preferably 1,500 or more, even more preferably 3,000 or more, and preferably 50,000 or less, more preferably 20,000 or less, even more preferably 15,000 or less, and even more preferably 10,000 or less.

The solubility parameters (SP _A ), acid value, hydroxyl value, softening point, glass transition temperature, number average molecular weight, and weight average molecular weight of resin (A) can be appropriately adjusted depending on the type and amount of raw material monomer used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate, and can be 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 solubility parameters (SP _A ), acid value, hydroxyl value, softening point, glass transition temperature, number average molecular weight, and weight average molecular weight of the resin (A) obtained as a mixture thereof are each within the above ranges.

[Amorphous resin (B)]
The toner binder resin composition of the present invention may contain an amorphous resin (B) (hereinafter also referred to as "resin (B)") from the viewpoint of obtaining a toner for electrostatic image development that has excellent low-temperature fixing properties and image heat resistance.

The resin (B) is not particularly limited, but is an amorphous resin having a softening point 5°C or more higher than the softening point of amorphous resin (A), and is preferably an amorphous polyester resin (B1) (hereinafter also referred to as "resin (B1)").
The difference in softening points between resin (A) and resin (B) is preferably 10°C or higher, more preferably 20°C or higher, even more preferably 25°C or higher, and preferably 80°C or lower, more preferably 60°C or lower, and even more preferably 50°C or lower, from the viewpoint of obtaining a toner for electrostatic image development that has excellent low-temperature fixability and image heat resistance.

Resin (B1) is, for example, an amorphous polyester resin containing a polycondensate of an alcohol component and a carboxylic acid component.
Examples of the resin (B1) include polyester resin and modified polyester resin. Examples of modified polyester resins include urethane-modified polyester resin, epoxy-modified polyester resin, and composite resins containing a polyester resin segment and an addition polymerization resin segment. Among these, amorphous polyester resin which is a polycondensate of an alcohol component and a carboxylic acid component is preferred.

<Alcohol content>
The alcohol components include those similar to those listed as the alcohol components of resin (A).

Examples of alkylene oxide adducts of bisphenol A include propylene oxide adducts of bisphenol A and ethylene oxide adducts of bisphenol A. One or more of these may be used. Among these, propylene oxide adducts of bisphenol A and combinations of propylene oxide adducts of bisphenol A and ethylene oxide adducts of bisphenol A are preferred.
If the alcohol component contains an alkylene oxide adduct of bisphenol A, the amount thereof is preferably 70 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less, and even more preferably 100 mol%.

<Carboxylic acid components>
Examples of carboxylic acid components include those listed as the carboxylic acid component of resin (A).
The carboxylic acid component includes a carboxylic acid compound with two or more valent values, and its content is preferably 80 mol% or more, more preferably 90 mol% or more, even more preferably 95 mol% or more, and 100 mol% or less of the carboxylic acid component.

Examples of aromatic dicarboxylic acid compounds include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid or terephthalic acid are preferred, and terephthalic acid is more preferred.
The amount of aromatic dicarboxylic acid compound is preferably 30 mol% or more, more preferably 40 mol% or more, even more preferably 50 mol% or more, and 100 mol% or less, in the carboxylic acid component.

As linear or branched aliphatic dicarboxylic acid compounds, succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms, or their anhydrides, are preferred.
If a linear or branched aliphatic dicarboxylic acid compound is included, its amount is preferably 2 mol% or more, more preferably 3 mol% or more, even more preferably 5 mol% or more, and preferably 20 mol% or less, more preferably 15 mol% or less, and even more preferably 10 mol% or less, of the carboxylic acid component.

As the polycarboxylic acid compound with a valency of 3 or higher, trimellitic acid or its anhydride is preferred.
When a trivalent or higher polycarboxylic acid compound is included, the amount of the trivalent or higher polycarboxylic acid compound is preferably 5 mol% or more, more preferably 10 mol% or more, even more preferably 15 mol% or more, and preferably 40 mol% or less, more preferably 35 mol% or less, and even more preferably 30 mol% or less, in the carboxylic acid component.

The ratio of carboxyl groups of the carboxylic acid component to hydroxyl groups of the alcohol component (COOH group/OH group) is preferably 0.7 or higher, more preferably 0.8 or higher, and preferably 1.3 or lower, more preferably 1.2 or lower.

When resin (B1) is a composite resin having a polyester resin segment and an addition polymerization resin segment, the addition polymerization segment is, for example, an addition polymerization product of raw material monomers containing a styrene-based compound. For details on composite resins, see Japanese Patent Publication No. 2021-026129.

If the amorphous resin (B) is an amorphous polyester resin, it may be manufactured, for example, by a process involving the polycondensation of an alcohol component and a carboxylic acid component.

In the polycondensation step, if necessary, an esterification catalyst such as di(2-ethylhexanoate)tin(II), dibutyltin oxide, or titanium diisopropoxybis(triethanolamine) may be used in an amount of 0.01 parts by mass to 5 parts by mass per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component; and an esterification co-catalyst such as gallic acid (same as 3,4,5-trihydroxybenzoic acid) may be used in an amount of 0.001 parts by mass to 0.5 parts by mass per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component for polycondensation.
Furthermore, when using monomers having unsaturated bonds, such as fumaric acid, in polycondensation, a radical polymerization inhibitor may be used, preferably in an amount of 0.001 parts by mass or more and 0.5 parts by mass or less, per 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. An example of a radical polymerization inhibitor is 4-tert-butylcatechol.
The temperature of the polycondensation reaction is preferably 120°C or higher, more preferably 160°C or higher, even more preferably 180°C or higher, and preferably 250°C or lower, more preferably 240°C or lower. The polycondensation may be carried out in an inert gas atmosphere.

(Physical properties of resin (B))
The solubility parameter (SP value) (SP _B ) calculated by the Fedors method from the alcohol and carboxylic acid components of resin (B) is preferably 11.0 (cal/ ^cm³ ) ^1/2 or less, more preferably 9.8 (cal/ ^cm³ ) ^1/2 or more, more preferably 10.0 (cal/cm³) ^1/2 or more, and even more preferably ^{10.2 (cal/cm³) 1/2 or more} .

The acid value of resin (B) is preferably 0.1 mg KOH/g or more, more preferably 0.5 mg KOH/g or more, even more preferably 1 mg KOH/g or more, and preferably 40 mg KOH/g or less, more preferably 30 mg KOH/g or less, and even more preferably 20 mg KOH/g or less.
The hydroxyl value of resin (B) is preferably 0.1 mg KOH/g or more, more preferably 10 mg KOH/g or more, even more preferably 20 mg KOH/g or more, and preferably 70 mg KOH/g or less, more preferably 60 mg KOH/g or less, and even more preferably 50 mg KOH/g or less.

The softening point of resin (B) is preferably 70°C or higher, more preferably 90°C or higher, and even more preferably 100°C or higher. Furthermore, from the viewpoint of further improving low-temperature fixability, it is preferably 160°C or lower, more preferably 150°C or lower, and even more preferably 145°C or lower.
The glass transition temperature of resin (B) is preferably 40°C or higher, more preferably 50°C or higher, and even more preferably 55°C or higher. From the viewpoint of further improving low-temperature fixation, it is preferably 80°C or lower, more preferably 75°C or lower, and even more preferably 70°C or lower.

The solubility parameters, acid value, hydroxyl value, softening point, and glass transition temperature of resin (B) can be appropriately adjusted depending on the type and amount of raw material monomer used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate. These values can be determined by the method described in the examples.
Furthermore, when using two or more types of resin (B) in combination, it is preferable that the solubility parameter, acid value, hydroxyl value, softening point, and glass transition temperature obtained from the mixture thereof are all within the aforementioned ranges.

In the toner binder resin composition of the present invention, when resin (B) is included, the mass ratio of resin (B) to resin (A) (resin (B) / resin (A)) is preferably 10/90 or more, more preferably 15/85 or more, even more preferably 30/70 or more, and preferably 90/10 or less, more preferably 70/30 or less, even more preferably 60/40 or less, and even more preferably 50/50 or less.

[Crystalline resin (C)]
The crystalline resin (C) contained in the toner binder resin composition of the present invention (hereinafter also simply referred to as "resin (C)") is preferably a crystalline polyester resin (C1) (hereinafter also referred to as "resin (C1)") which is a polycondensate of an alcohol component and a carboxylic acid component. From the viewpoint of improving the low-temperature fixability of the toner, the crystalline resin (C) preferably has acidic groups.

<Alcohol content>
The alcohol component includes an aliphatic diol, and an α,ω-aliphatic diol is preferred.
The number of carbon atoms in the aliphatic diol is preferably 2 or more, more preferably 4 or more, even more preferably 6 or more, and preferably 16 or less, more preferably 14 or less, and even more preferably 12 or less.
Examples of aliphatic diols 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, as well as 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, 1,10-decanediol, and 1,12-dodecanediol are more preferred, and 1,12-dodecanediol is even more preferred.

The amount of aliphatic diol is preferably 40 mol% or more, more preferably 45 mol% or more, even more preferably 50 mol% or more, and 100 mol% or less, in the alcohol component.

The alcohol component may contain alcohol components other than aliphatic diols. Examples of other alcohol components include alkylene oxide adducts of aromatic diols such as alkylene oxide adducts of bisphenol A; trivalent or higher alcohols such as glycerin, pentaerythritol, and trimethylolpropane; and long-chain monovalent alcohols such as stearyl alcohol. One or more of these alcohol components may be used.

<Carboxylic acid components>
The carboxylic acid component contains an aliphatic dicarboxylic acid compound. A linear aliphatic dicarboxylic acid compound is preferred as the aliphatic dicarboxylic acid compound.
The number of carbon atoms in the aliphatic dicarboxylic acid compound is preferably 4 or more, preferably 14 or less, and more preferably 12 or less.
Examples of preferred aliphatic dicarboxylic acid compounds include fumaric acid, sebacic acid, dodecanediic acid, and tetradecanediic acid. Among these, dodecanediic acid and sebacic acid are more preferred. One or more of these carboxylic acid components may be used.

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

The carboxylic acid component may contain other carboxylic acid components different from aliphatic dicarboxylic acid compounds. Examples of other carboxylic acid components include aromatic dicarboxylic acid compounds such as terephthalic acid and isophthalic acid; polycarboxylic acid compounds with a valency of three or more; and long-chain monovalent carboxylic acids such as stearic acid. One or more of these carboxylic acid components may be used.

The equivalent ratio [COOH group/OH group] of the carboxyl group of the carboxylic acid component to the hydroxyl group of the alcohol component is preferably 0.7 or higher, more preferably 0.8 or higher, and preferably 1.5 or lower, more preferably 1.4 or lower.
(Physical properties of resin (C))

The solubility parameter (SP value) (SP _C ) of resin (C) obtained by the Fedors method is 9.6 (cal/ ^cm³ ) ^1/2 or less, from the viewpoint of obtaining a toner binder resin composition that provides a toner with excellent low-temperature fixability and image heat resistance. Preferably it is 8.9 (cal/ ^cm³ ) ^1/2 or more, more preferably 9.1 (cal/ ^cm³ ) ^1/2 or more, and even more preferably 9.3 (cal/ ^cm³ ) ^1/2 or more.

The acid value of resin (C) is preferably 1 mg KOH/g or more, more preferably 3 mg KOH/g or more, even more preferably 5 mg KOH/g or more, and preferably 40 mg KOH/g or less, more preferably 30 mg KOH/g or less, and even more preferably 20 mg KOH/g or less, from the viewpoint of improving the low-temperature fixability of the toner.

The softening point of resin (C) is preferably 55°C or higher, more preferably 60°C or higher, even more preferably 65°C or higher, and preferably 110°C or lower, more preferably 100°C or lower, and even more preferably 95°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 65°C or higher. Furthermore, 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 solubility parameters (SP _C ), acid value, softening point, and melting point of resin (C) can be appropriately adjusted depending on the type and amount of raw material monomer used, as well as manufacturing conditions such as reaction temperature, reaction time, and cooling rate, and can be 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 solubility parameters (SP _C ), acid value, softening point, and melting point of the resin (C) obtained as a mixture thereof are within the aforementioned ranges.

The mass ratio of resin (C) to resin (A) (resin (C) / resin (A)) is preferably 1/99 or more, more preferably 5/95 or more, even more preferably 10/90 or more, and preferably 50/50 or less, more preferably 30/70 or less, and even more preferably 20/80 or less.
Furthermore, the mass ratio of resin (C) to the total mass of resin (A) and resin (B) (resin (C) / resin (A) + resin (B)) is preferably 1/99 or more, more preferably 3/97 or more, even more preferably 5/95 or more, and preferably 50/50 or less, more preferably 40/60 or less, and even more preferably 30/70 or less.

[Toner for developing electrostatic images]
An electrostatic image developing toner according to one embodiment of the present invention (hereinafter also simply referred to as "toner") is an electrostatic image developing toner containing a binder resin, wherein the binder resin contains the toner binder resin composition of the present invention described above.
According to the present invention, it is possible to provide a toner for electrostatic image development that provides excellent low-temperature fixing properties and image heat resistance.
The toner for developing electrostatic images contains at least the above-mentioned binder resin, and may also contain other components such as colorants, release agents, and charge control agents. Preferably, the toner for developing electrostatic images contains toner matrix particles (hereinafter also referred to as "toner particles") and external additives added to the toner matrix particles.

<Coloring agents>
As a coloring agent, all dyes, pigments, etc. used as coloring agents for toners can be used, including carbon black, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, disazo yellow, etc., and the toner of the present invention may be either a black toner or any other color toner.

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

<Release agent>
Examples of release agents include hydrocarbon waxes, ester waxes, silicone waxes, and fatty acid amide waxes.

The melting point of the release agent is preferably 60°C or higher, more preferably 70°C or higher, and more preferably 160°C or lower, more preferably 150°C or lower, and even more preferably 140°C or lower.
Furthermore, when using two or more release agents in combination, it is preferable that the melting points of each release agent are within the aforementioned range.

The release agent content is preferably 0.5 parts by mass or more, more preferably 1.0 part by mass or more, even more preferably 1.5 parts by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less, based on 100 parts by mass of the total amount of binder resin.

<Charge Control Agent>
The charge control agent may contain either a positively charged charge control agent or a negatively charged charge control agent.
Positively charged charge control agents include nigrosine dyes, such as "Nigrosine Base EX,""Oil Black BS,""Oil Black SO,""BontronN-01,""BontronN-04,""BontronN-07,""BontronN-09,""BontronN-11," and "Bontron N-79" (all manufactured by Orient Chemical Industry Co., Ltd.); triphenylmethane-based 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, and "COPY CHARGE PX." Examples include VP435 (manufactured by Clariant), polyamine resins such as AFP-B (manufactured by Orient Chemical Industries, Ltd.), imidazole derivatives such as PLZ-2001 and PLZ-8001 (both manufactured by Shikoku Chemicals, Ltd.), and styrene-acrylic resins such as FCA-701PT (manufactured by Fujikura Chemicals, Ltd.).

Examples of negatively charged charge control agents include metal-containing azo dyes, such as "Barifast Black 3804,""BontronS-31,""BontronS-32,""BontronS-34," and "Bontron S-36" (all manufactured by Orient Chemical Industries, Ltd.), "Eisenspiron Black TRH," and "T-77" (manufactured by Hodogaya Chemical Co., Ltd.); metal compounds of benzyl 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,""BontronE-84,""BontronE-88," and "Bontron E-304" (all manufactured by Orient Chemical Industries, Ltd.), and "TN-105" (manufactured by Hodogaya Chemical Co., Ltd.); copper phthalocyanine dyes; quaternary ammonium salts, such as "COPY CHARGE NX VP434" (manufactured by Clariant), nitroimidazole derivatives, etc.; and organometallic compounds.
The charge control agent to be used should be selected appropriately according to the characteristics of the printing press using toner and the type of colorant used.

The charge control agent content 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 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, based on 100 parts by mass of the total amount of binder resin.

[Toner manufacturing method]
The toner may be obtained by any known method such as the melt-kneading method, the emulsification-phase inversion method, the polymerization method, or the emulsification-coagulation method, but from the viewpoint of productivity, pulverized toner obtained by the melt-kneading method is preferred.
In the case of pulverized toner produced by the melt-kneading method, for example, raw materials such as resin (A) and resin (C), and optionally resin (B), colorants, release agents, and charge control agents, can be uniformly mixed in a mixer such as a Henschel mixer, then melt-kneaded in a closed-type kneader, a single-screw or twin-screw extruder, an open-roll type kneader, etc., followed by cooling, pulverization, and classification.
The method for producing toner preferably includes a step of melting and kneading a mixture containing resin (A) and resin (C), and optionally resin (B), etc., at a temperature in the range of 80°C to 200°C. The melting and kneading temperature is preferably 80°C or higher, more preferably 90°C or higher, and preferably 200°C or lower, more preferably 180°C or lower.
A method for producing toner preferably includes the step of grinding and classifying a mixture obtained by melt kneading to obtain toner particles. This grinding and classification can be carried out by known methods.

The volume median particle size (D ₅₀ ) of the toner particles is preferably 2 μm or larger, more preferably 3 μm or larger, and even more preferably 4 μm or larger, from the viewpoint of obtaining a toner for electrostatic image development that has excellent low-temperature fixing properties and image heat resistance, and is 8 μm or smaller, preferably 7 μm or smaller, and more preferably 6.8 μm or smaller, from the viewpoint of hot offset resistance.

It is preferable that the toner is treated by adding fluidizing agents or the like as external additives to the surface of the toner particles.
Examples of external additives include inorganic material nanoparticles such as hydrophobic silica, titanium dioxide nanoparticles, alumina nanoparticles, cerium oxide nanoparticles, and carbon black, as well as polymer nanoparticles such as polycarbonate, polymethyl methacrylate, and silicone resin. Among these, hydrophobic silica is preferred.
When using external additives, the amount of external additive added is preferably 0.5 parts by mass or more, 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, per 100 parts by mass of toner particles.

Toner is used, for example, in developing latent images formed in electrophotography, electrostatic recording, and electrostatic printing. Toner can be used as a one-component developer or, when mixed with a carrier, as a two-component developer.

The present invention will be specifically described below with reference to examples, but the present invention is not limited in any way by these examples. The physical properties of the resin and the like were measured by the following methods.
In notations such as "alkylene oxide (X)," the number X in parentheses represents the average number of moles of alkylene oxide added.

[Measurement method]
[Acid value and hydroxyl value of resins]
The acid value and hydroxyl value of the resins were measured according to the method of JIS K0070:1992. However, the measurement solvent was changed from the ethanol and ether mixture specified in JIS K0070:1992 to an acetone and toluene mixture [acetone:toluene = 1:1 (volume ratio)] for amorphous resins, and to chloroform for crystalline resins.

[Amine value of modified silicone]
The total amine value of the modified silicone was measured according to the ASTM D2073 method. However, the measurement solvent was changed from ethanol to toluene as specified in ASTM D2073.

[Number-average molecular weight and weight-average molecular weight of resins]
The molecular weight distribution was measured by gel permeation chromatography (GPC), obtained using the following method, and the number-average molecular weight and weight-average molecular weight were 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 to a concentration of 0.5 g/100 mL. Then, this solution was filtered using a fluoropolymer filter "DISMIC-25JP" (manufactured by ADVANTEC) with a pore size of 0.2 μm to remove undissolved material and obtain the sample solution.
(2) Molecular weight measurement Using the following measuring apparatus and analytical column, tetrahydrofuran (amorphous resin) or chloroform (crystalline resin) was flowed as the eluent at a flow rate of 1 mL per minute, and the column was stabilized in a constant temperature bath at 40°C. 100 μL of the sample solution was injected into the column and the measurement was performed. The molecular weight of the sample was calculated based on a calibration curve prepared in advance. The calibration curve used in this study was prepared using several types of monodisperse polystyrene as standard samples: "A-500" (5.0 × ^10² ), "A-1000" (1.01 × ^10³ ), "A-2500" (2.63 × ^10³ ), "A-5000" (5.97 × ^10³ ), "F-1" (1.02 × ^10³ ), "F-2" (1.81 × ^10⁴ ), "F-4" (3.97 × ^10⁴ ), "F-10" (9.64 × ^10⁴ ), "F-20" (1.90 × ^10⁵ ), "F-40" (4.27 × ^10⁵ ), "F-80" (7.06 × ^10⁵ ), and "F-128" (1.09 × ^10⁶ ) (all manufactured by Tosoh Corporation).
Measuring device: "HLC-8220CPC" (manufactured by Tosoh Corporation)
Analysis columns: "GMHXL" + "G3000HXL" (manufactured by Tosoh Corporation)

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

[Glass transition temperature of amorphous resins]
Using a differential scanning calorimeter "Q-20" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.01 to 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and then cooled to 0°C at a rate of 10°C/min. Next, the sample was heated at a rate of 10°C/min, and 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 rise of the peak to the peak apex was defined as the glass transition temperature.

[Melting point of crystalline resins]
Using a differential scanning calorimeter "Q-100" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.01 to 0.02 g of the sample was weighed into an aluminum pan and cooled from room temperature to -10°C at a rate of 10°C/min, holding the temperature for 1 minute. Next, the sample was heated to 200°C at a rate of 10°C/min, and then cooled from that temperature to -30°C at a rate of 10°C/min. Next, the sample was heated again at a rate of 10°C/min, and the peak temperature on the highest endothermic side of the observed endothermic peaks was defined as the melting point.

[Melting point of release agent]
Using a differential scanning calorimeter "Q-100" (manufactured by T.A. Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, heated to 200°C, and then cooled from 200°C to 0°C at a rate of 10°C/min. Next, the sample was heated again at a rate of 10°C/min, and the amount of heat was measured. The maximum peak temperature of the obtained endothermic reaction was defined as the melting point.

[Medium volume particle size of toner particles (D ₅₀ )]
The median volume particle size (D ₅₀ ) of the toner particles was measured as follows:
• Measuring device: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.)
Aperture diameter: 50 μm
• Analysis software: "Coulter Multisizer (registered trademark) III version 3.51" (manufactured by 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 sample was added to 5 mL of the dispersion, dispersed for 1 minute using an ultrasonic disperser, then 25 mL of electrolyte was added, and dispersed again for 1 minute using an ultrasonic disperser to prepare the sample dispersion.
Measurement conditions: The sample dispersion was added to 100 mL of the electrolyte in a beaker to adjust the concentration to one that could measure the particle size of 30,000 particles in 20 seconds. The 30,000 particles were then measured, and the median volume particle size (D ₅₀ ) was determined from the resulting particle size distribution.

[Toner Evaluation]
[Minimum fixing temperature]
Toner was loaded into a modified fuser unit of a Sharp AR-505 copier, allowing for external fixing, and an unfixed printout was obtained (print area: 2 cm x 12 cm, adhesion amount: 0.5 mg/ ^cm² ). Subsequently, using a fuser unit adjusted to a total fixing pressure of 30 kgf (fixing speed 300 mm/sec), the fixing test of the unfixed printout was performed at each temperature while sequentially increasing the temperature of the fuser roll from 100°C to 240°C in 5°C increments. Cellophane adhesive tape "UNICEF Cellophane" (Mitsubishi Pencil Co., Ltd., width: 18 mm, JIS Z 1522) was attached to the image portion of the obtained printout, and after passing it through a fuser roller set to 30°C, the tape was removed. The paper used for printing was "CopyBond SF-70NA" (Sharp Corporation, 75 g/ ^m² ).
The optical reflectance density before and after applying the tape was measured using a reflectance densitometer "RD-915" (manufactured by Gretag Macbeth). The minimum fixing temperature was defined as the temperature of the fixing roller at which the ratio of the two (after removal / before application × 100) first exceeded 90%. A lower minimum fixing temperature indicates better low-temperature fixing performance.

[Image heat resistance]
Toner was loaded into a modified fuser unit of a Sharp AR-505 copier, allowing for external fixing, and a printout was obtained in an unfixed state (print area: 2 cm x 12 cm, toner adhesion: 0.5 mg/ ^cm² ). Subsequently, the unfixed printout was fixed using a fuser unit adjusted to a total fixing pressure of 30 kgf (fixing speed 300 mm/sec) with the fuser roll temperature set to 140°C. The paper used for printing was "CopyBond SF-70NA" (Sharp Corporation, 75 g/ ^m² ).
The fixed images were superimposed and left for one day under conditions of a load of 100 g/ ^cm² , a temperature of 60°C, and a humidity of 50%. After one day, the presence or absence of document offset was visually checked when the images were peeled apart. The results obtained were evaluated according to the following criteria.
A: The document offset cannot be confirmed.
B: No peeling of the fixed image was observed, but slight sticking occurred when peeling it off.
C: When peeling, sticking occurs, and slight peeling (such as white spots) may occur in the fixed image.
D: When peeling it off, it sticks, and white areas are clearly visible in the fixed image.
E: The papers are stuck together and will be damaged if you try to separate them.

[Resin manufacturing]
Manufacturing Example A1 (Manufacturing of Resin A-1)
The alcohol component, carboxylic acid component, amino-modified silicone, esterification catalyst, and esterification co-catalyst shown in Table 1-1 were placed in a 10-liter four-necked flask equipped with a thermometer, stainless steel stirring rod, fractionation column, dehydration tube, condenser, and nitrogen inlet tube. The mixture was heated to 235°C in a mantle heater under a nitrogen atmosphere and reacted at atmospheric pressure for 4 hours. Subsequently, the reaction was carried out under reduced pressure at 235°C and 8 kPa until the desired acid value and softening point were reached, yielding silicone-modified amorphous polyester resin A-1. Various physical properties are shown in Table 1-1.

Manufacturing Examples A2 to A4 and A6, and Comparative Manufacturing Examples A'2 and A'3 (Manufacturing of resins A-2 to A-4 and A-6, and resins A'-2 and A'-3)
Except for changing the types and amounts of alcohol component, carboxylic acid component, amino-modified silicone, esterification catalyst, and esterification co-catalyst as shown in Tables 1-1 and 1-2, the reaction was carried out under the same conditions as in Production Example A1 until the desired acid value and softening point were obtained, yielding silicone-modified amorphous polyester resins A-2 to A-4, A-6, and resins A'-2 and A'-3. Various physical properties are shown in Tables 1-1 and 1-2.

Manufacturing Example A5 (Manufacturing of Resin A-5)
The alcohol components, terephthalic acid, amino-modified silicone, esterification catalyst, and esterification co-catalyst shown in Table 1-1 were placed in a 10-liter four-necked flask equipped with a thermometer, stainless steel stirring rod, fractionation column, dehydration tube, condenser, and nitrogen inlet tube. The mixture was heated to 235°C in a mantle heater under a nitrogen atmosphere and the reaction was carried out under reduced pressure of 8 kPa for 1 hour. After that, the mixture was cooled to 180°C at atmospheric pressure, and the fumaric acid and radical polymerization inhibitor shown in Table 1-1 were added. The mixture was then gradually heated to 210°C at a rate of 10°C/h. Subsequently, the reaction was carried out under reduced pressure at 210°C and 16 kPa until the desired softening point was reached, yielding silicone-modified amorphous polyester resin A-5. Various physical properties are shown in Table 1-1.

Comparative manufacturing example A'1 (Manufacturing of resin A'-1)
The alcohol component, carboxylic acid component, esterification catalyst, and esterification co-catalyst shown in Table 1-2 were placed in a 10-liter four-necked flask equipped with a thermometer, stainless steel stirring rod, fractionation column, dehydration tube, condenser, and nitrogen inlet tube. The reaction was carried out under the same conditions as in Production Example A1 until the desired acid value and softening point were reached, yielding amorphous polyester resin A'-1. Various physical properties are shown in Table 1-2.

In Tables 1-1 and 1-2, the amino-modified silicones used have the following composition.
• KF-864: Modified silicone "KF-864" (modified silicone having monoamino groups in its side chains, kinematic viscosity (25°C) = 1,700 ^mm² /s, molecular weight = 30,000, functional group equivalent = 3,800 g/mol, total amine value 14.7 mg KOH/g, manufactured by Shin-Etsu Chemical Co., Ltd.)
• KF-865: Modified silicone oil "KF-865" (modified silicone with monoamino groups in its side chains, kinematic viscosity (25°C) = 110 ^mm² /s, molecular weight = 5,000, functional group equivalent = 5,000 g/mol, total amine value 11.2 mg KOH/g, manufactured by Shin-Etsu Chemical Co., Ltd.)
• KF-8012: Modified silicone oil "KF-8012" (silicone with amino groups at both ends, kinematic viscosity (25°C) = 90 ^mm² /s, molecular weight = 4,400, functional group equivalent = 2,200 g/mol, total amine value 25.5 mg KOH/g, manufactured by Shin-Etsu Chemical Co., Ltd.)
• KF-8008: Modified silicone oil "KF-8008" (silicone with amino groups at both ends, kinematic viscosity (25°C) = 450 ^mm² /s, molecular weight = 11,400, functional group equivalent = 5,700 g/mol, total amine value 9.8 mg KOH/g, manufactured by Shin-Etsu Chemical Co., Ltd.)

Manufacturing Example B1 (Manufacturing of Resin B-1)
2450 g of bisphenol A propylene oxide (2.2) adduct and 2275 g of bisphenol A ethylene oxide (2.2) adduct as alcohol components, 1322 g of terephthalic acid and 188 g of dodecenyl succinic anhydride as carboxylic acid components, 20.4 g of tin(II) di(2-ethylhexanoate) as an esterification catalyst, and 2.04 g of gallic acid monohydrate as an esterification co-catalyst were placed in a 10-liter four-necked flask equipped with a thermometer, stainless steel stirring rod, fractionation column, dehydration tube, condenser, and nitrogen inlet tube. The mixture was heated to 235°C in a mantle heater while stirring under a nitrogen atmosphere, and the reaction was carried out at atmospheric pressure for 2.5 hours, followed by a reaction under reduced pressure of 8 kPa for 1 hour. After that, the mixture was cooled to 190°C at atmospheric pressure, 554 g of trimellitic anhydride was added, and the temperature was gradually increased to 210°C at a rate of 10°C/h. Subsequently, the reaction was carried out at 8 kPa until the desired softening point was reached, yielding amorphous polyester resin B-1. Various physical properties are shown in Table 2.

Manufacturing Example C1 (Manufacturing of Resin C1-1)
The alcohol component, carboxylic acid component, esterification catalyst, and polymerization inhibitor shown in Table 3 were placed in a 10-liter four-necked flask equipped with a thermometer, stainless steel stirring rod, fractionation column, dehydration tube, condenser, and nitrogen inlet tube. The mixture was heated to 140°C in a mantle heater under a nitrogen atmosphere and reacted for 5 hours. After that, the temperature was gradually increased to 200°C at a rate of 10°C/h. The reaction was then carried out at 8 kPa until the desired softening point was reached, yielding crystalline polyester resin C1-1. Various physical properties are shown in Table 3.

Manufacturing Example C2 and Comparative Manufacturing Example C'1 (Manufacturing of Resins C1-2 and C1'-1)
Except for changing the types and amounts of alcohol, carboxylic acid, esterification catalyst, and polymerization inhibitor as shown in Table 3, the reaction was carried out under the same conditions as in Production Example C1 until the desired softening point was obtained, yielding crystalline polyester resins C1-2 and C1'-1. The various physical properties are shown in Table 3.

[Toner Manufacturing]
Example 1
Sixty parts by mass of amorphous resin A-1, thirty parts by mass of amorphous resin B-1, ten parts by mass of crystalline polyester resin C1-1, five parts by mass of the coloring agent "ECB-301" (manufactured by Dainichi Seika Kogyo Co., Ltd.), one part by mass of the charge control agent "LR-147" (manufactured by Nippon Carlit Co., Ltd.), and two parts by mass of the release agent "HNP-9" (manufactured by Nippon Seiro Co., Ltd., paraffin wax, melting point: 75°C) were thoroughly mixed in a Henschel mixer, and then melt-kneaded using a co-rotating twin-screw extruder with a total length of 1560 mm in the kneading section, a screw diameter of 42 mm, and a barrel inner diameter of 43 mm. The screw rotation speed was 200 r/min, the heating setting temperature inside the screw was 90°C, the temperature of the kneaded material was 140°C, the supply rate of the kneaded material was 10 kg/h, and the average residence time was approximately 18 seconds. The resulting mixture was cooled from 140°C to 50°C in 1.5 hours, then rolled and cooled at 50°C using cooling rollers. After standing at 45°C for 4 hours, it was crushed and classified using a jet mill to obtain toner particles with a medium volume particle size (D ₅₀ ) of 5.5 μm.
To 100 parts by mass of the obtained toner particles, 1.0 part by mass of the external additive "AEROSIL NAX 50" (manufactured by Nippon Aerosil Co., Ltd., hydrophobic silica, hydrophobic treatment agent: HMDS, number average particle size: approximately 30 nm) was added, and the mixture was mixed in a Henschel mixer at 3600 r/min for 5 minutes to obtain the toner. The minimum fixing temperature and image heat resistance were evaluated using the method described in [Toner Evaluation] above. The evaluation results are shown in Table 4.

Examples 2-8 and Comparative Examples 1-5
Except for changing the binder resin as shown in Table 4, toners for Examples 2-8 and Comparative Examples 1-5 were obtained in the same manner as in Example 1. The evaluation results are shown in Table 4.

The results from the examples and comparative examples show that the electrostatic image developing toner containing the toner binder resin composition of the present invention exhibits excellent low-temperature fixing properties and image heat resistance.
On the other hand, the toners of Comparative Examples 1 and 2, which used a toner binder resin composition containing resin C1'-1 as the crystalline resin (C) with an SP value greater than 9.6 (cal/ ^cm³ ) ^1/2 , exhibited poor image heat resistance.
Furthermore, the toner of Comparative Example 3, which used a toner binder resin composition containing resin A'-1 that does not contain modified silicone-derived parts instead of amorphous resin (A), the toner of Comparative Example 4, which used a toner binder resin composition containing resin A'-2 that contains modified silicone-derived parts with a total amine value of less than 10.0 mgKOH/g as amorphous resin (A), and the toner of Comparative Example 5, which used a toner binder resin composition containing resin A'-3 with an SP value greater than 11.0 (cal/ ^cm³ ) ^1/2 as amorphous resin (A), all had high minimum fixing temperatures and poor low-temperature fixing properties. This is thought to be due to insufficient compatibility between the amorphous resin and the crystalline resin.
Furthermore, the results from Examples 4 and 5 and the Comparative Example show that, regardless of the magnitude of the difference between SP _A and SP _C (ΔSP), if the SP values of the amorphous resin (A) and the crystalline resin (C) contained in the toner binder resin composition are within a specific range, a toner for electrostatic image development with excellent low-temperature fixing properties and image heat resistance can be obtained.

Claims (7)

A method for producing a binder resin composition for toner, comprising an amorphous resin (A) which is a polycondensate of an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid compound, and a modified silicone having a polar group, and a crystalline resin (C),
The aforementioned polar group is one of an amino group, a carboxyl group, a hydroxyl group, or an epoxy group.
The solubility parameter (SP value) (SP _A ) of Fedors calculated from the alcohol and carboxylic acid components of the amorphous resin (A) is 11.0 (cal/ ^cm³ ) ^1/2 or less, the polarity value of the modified silicone is 10.0 mg KOH/g or more, and the SP value (SP _C ) of the crystalline resin (C) is 9.6 (cal/ ^cm³ ) ^1/2 or less.
A method for producing a binder resin composition for toner, wherein the polarity value of the modified silicone is the value obtained by converting the polar groups of 1 g of the modified silicone into the number of mg of potassium hydroxide. The method for producing a toner binder resin composition according to claim 1, wherein the modified silicone has repeating units represented by formula (1) and repeating units represented by formula (2).
[In formula (1), R is independently a hydrocarbon group having 1 to 6 carbon atoms, 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 carboxyl group, an epoxy group, or a hydroxyl group, and * is a bonding site.]
[In formula (2), R is independently a hydrocarbon group having 1 to 6 carbon atoms, and * is a bonding site.] A method for producing a toner binder resin composition according to claim 2, wherein X is an amino group. A method for producing a toner binder resin composition according to any one of claims 1 to 3, wherein the amount of modified silicone added to the amorphous resin (A) is 0.1 parts by mass or more and 9 parts by mass or less per 100 parts by mass of the theoretical yield of polyester obtained from the alcohol component and carboxylic acid component in the raw materials of the amorphous resin (A). A method for producing a toner binder resin composition according to any one of claims 1 to 3, wherein the crystalline resin (C) is a crystalline polyester resin (C1). A method for producing a toner binder resin composition according to any one of claims 1 to 3, wherein the mass ratio of the crystalline resin (C) to the amorphous resin (A) (crystalline resin (C) / amorphous resin (A)) is 1/99 or more and 50/50 or less. A method for producing toner for electrostatic image developing, comprising: step I for producing a toner binder resin composition containing an alcohol component containing a divalent or higher alcohol, a carboxylic acid component containing a divalent or higher carboxylic acid compound, an amorphous resin (A) which is a polycondensate of a modified silicone having a polar group, and a crystalline resin (C); and step II for mixing raw materials containing the toner binder resin composition, melt-kneading, cooling, grinding, and classifying,
The aforementioned polar group is one of an amino group, a carboxyl group, a hydroxyl group, or an epoxy group.
In step I, the solubility parameter (SP value) (SP _A ) of Fedors calculated from the alcohol and carboxylic acid components of the amorphous resin (A) is 11.0 (cal/ ^cm³ ) ^1/2 or less, the polarity value of the modified silicone is 10.0 mg KOH/g or more, and the SP value (SP _C ) of the crystalline resin (C) is 9.6 (cal/ ^cm³ ) ^1/2 or less.
A method for producing toner for electrostatic image developing, wherein the polarity value of the modified silicone is the value obtained by converting the polar groups present in 1 g of the modified silicone into the number of mg of potassium hydroxide.