JP2024085398A - Toner Binder - Google Patents

Abstract

[Problem] The object is to provide a toner binder and toner that satisfy all of low-temperature fixing properties, hot offset resistance, storage stability under high-temperature and high-humidity conditions, and hydrolysis resistance. [Solution] A toner binder containing a crystalline vinyl resin (A), the crystalline vinyl resin (A) being a polymer of a monomer composition (A0) containing a monomer (a) and a monomer (b), the monomer (a) being a (meth)acrylate having 21 to 40 carbon atoms and a chain-like hydrocarbon group, the monomer (b) being a monomer having an amide bond and a cyclic structure, and the weight ratio of the monomer (a) based on the weight of the monomer composition (A0) being 40 to 90% by weight. [Selected Drawing] None

Description

The present invention relates to a toner binder.

Toner binders for the thermal fixing method generally adopted as an image fixing method in copiers, printers, etc. are required to achieve a balance between low-temperature fixing property, hot offset resistance, storage stability, etc. For this reason, the toner binder is required to change its storage modulus to an appropriate value around the fixing temperature, such that the storage modulus is high at temperatures lower than the fixing temperature, the storage modulus decreases in a short time at the temperature at which fixing begins, and a constant storage modulus is maintained up to a high temperature.
As a method for satisfying the above-mentioned thermal properties of a toner binder, a technique of using a crystalline resin has been proposed. However, the crystalline resin has a problem in that the molecular weight decreases due to hydrolysis during long-term storage or under high temperature and humidity conditions, and the decrease in molecular weight is particularly remarkable when used in combination with an amorphous resin having an acid value.
In recent years, a technique has been proposed in which a polymer of a monomer having an ethylenically unsaturated bond, which has excellent resistance to hydrolysis, is given crystallinity and used as a toner binder (Patent Documents 1 and 2). However, even in this case, there is a problem that hydrolysis occurs under specific high-temperature and high-humidity conditions, causing changes in the physical properties of the resin.

JP 2019-200415 A JP 2019-219652 A

The present invention aims to provide a toner binder and toner that satisfy all of the following requirements: low-temperature fixability, hot offset resistance, storage stability under high-temperature and high-humidity conditions, and hydrolysis resistance.

The inventors have conducted extensive research and have arrived at the present invention. That is, the present invention is a toner binder containing a crystalline vinyl resin (A), the crystalline vinyl resin (A) being a polymer of a monomer composition (A0) containing a monomer (a) and a monomer (b), the monomer (a) being a (meth)acrylate having 21 to 40 carbon atoms and a chain-like hydrocarbon group, the monomer (b) being a monomer having an amide bond and a cyclic structure, and the weight ratio of the monomer (a) being 40 to 90% by weight based on the weight of the monomer composition (A0).

The present invention makes it possible to provide a toner binder and toner that satisfy all of the following requirements: low-temperature fixability, hot offset resistance, storage stability under high temperature and high humidity conditions, and hydrolysis resistance.

The toner binder of the present invention is a toner binder containing a crystalline vinyl resin (A). The crystalline vinyl resin (A) is a crystalline vinyl resin, and is a polymer of a monomer composition (A0) containing a monomer (a) which is a (meth)acrylate having 21 to 40 carbon atoms and a chain hydrocarbon group, and a monomer (b) which has an amide bond and a cyclic structure.
In the present invention, "crystalline" means that there is a maximum in the differential scanning calorimetry (DSC) curve during the temperature rise process obtained by the differential scanning calorimetry (DSC) described below, and that there is a peak top temperature of the endothermic peak.

The method for measuring the peak top temperature of the endothermic peak of the crystalline vinyl resin (A) is described below.
The measurement is performed using a differential scanning calorimeter {e.g., "DSCQ20" [manufactured by TA Instruments Co., Ltd.]}. The crystalline vinyl resin (A) is heated for the first time from 20°C to 150°C at 10°C/min, then cooled from 150°C to 0°C at 10°C/min, and then heated for the second time from 0°C to 150°C at 10°C/min. The temperature showing the top of the endothermic peak during the second heating process is taken as the peak top temperature of the endothermic peak of the crystalline vinyl resin (A).

The monomer (a) is a (meth)acrylate having a chain hydrocarbon group and a carbon number of 21 to 40. The carbon number of the monomer (a) is preferably 21 to 36, and more preferably 21 to 34. If the carbon number of the monomer (a) is less than 21, the crystallinity and storage stability under high temperature and high humidity conditions deteriorate, and if the carbon number exceeds 40, the low temperature fixability deteriorates.
The monomer (a) may be used alone or in combination of two or more kinds.
In the present invention, "(meth)acrylate" means "acrylate" and/or "methacrylate".

Examples of the monomer (a) include (meth)acrylates having a linear alkyl group (the alkyl group has 18 to 36 carbon atoms) [octadecyl (meth)acrylate (stearyl (meth)acrylate), nonadecyl (meth)acrylate, eicosyl (meth)acrylate, heneicosanyl (meth)acrylate, behenyl (meth)acrylate, lignoceryl (meth)acrylate, ceryl (meth)acrylate, montanyl (meth)acrylate, triacontyl (meth)acrylate, dotriacontyl (meth)acrylate, and the like] and (meth)acrylates having a branched alkyl group (the alkyl group has 18 to 36 carbon atoms) [2-decyltetradecyl (meth)acrylate, and the like].
Among these, from the viewpoints of crystallinity, storage stability under high temperature and high humidity conditions, and low temperature fixability, preferred are (meth)acrylates having a linear alkyl group (alkyl group having 18 to 36 carbon atoms), more preferred are (meth)acrylates having a linear alkyl group (alkyl group having 18 to 30 carbon atoms), still more preferred are octadecyl (meth)acrylate (stearyl (meth)acrylate), eicosyl (meth)acrylate, behenyl (meth)acrylate, lignoceryl (meth)acrylate, ceryl (meth)acrylate, and triacontyl (meth)acrylate, particularly preferred are octadecyl acrylate (stearyl acrylate), eicosyl acrylate, behenyl acrylate, and lignoceryl acrylate, and most preferred is behenyl acrylate.

The monomer (b) is a monomer having an amide bond and a cyclic structure. The monomer (b) may be used alone or in combination of two or more kinds.
If the monomer (b) has an amide bond, the storage stability, hydrolysis resistance, and hot offset resistance under high temperature and high humidity conditions are improved, and if it has a cyclic structure, the low temperature fixability, storage stability, hydrolysis resistance, and offset resistance under high temperature and high humidity conditions are improved. It is assumed that by using a monomer having an amide bond and a cyclic structure, the storage stability and hydrolysis resistance under high temperature and high humidity conditions are improved because the bulkiness of the cyclic group makes it easier for steric repulsion to occur when water molecules approach the amide group compared to a monomer having a non-cyclic structure, and in addition, the effect of the polar group derived from the amide group causes a chemical interaction between the toner binder and the fixing paper, improving the low temperature fixability and hot offset resistance.

The monomer (b) is not particularly limited as long as it is a monomer having an amide bond and a cyclic structure, but from the viewpoint of low-temperature fixing property and hot offset resistance, compounds represented by the following general formula (1) and/or (2) are preferred.

In general formula (1), R ¹ is a hydrogen atom or a methyl group, and R ² is an alkylene group having 2 to 5 carbon atoms.

Examples of the alkylene group having 2 to 5 carbon atoms for ^R2 include an ethylene group, a propylene group (1,2-propylene group), a trimethylene group (1,3-propylene group), a tetramethylene group, a pentamethylene group, etc. Among ^R2 , from the viewpoints of low-temperature fixing ability and hot offset resistance, ^R2 is preferably an alkylene group having 3 to 4 carbon atoms, more preferably an alkylene group having 3 carbon atoms.

Specific examples of the compound represented by general formula (1) include N-vinylpyrrolidone, N-vinylpiperidone, and N-vinylcaprolactam. Of these, N-vinylpyrrolidone is preferred from the viewpoints of low-temperature fixing ability and hot offset resistance.

In formula (2), R ³ represents a hydrogen atom or a methyl group, R ⁴ each independently represents an alkylene group having 1 to 5 carbon atoms, and X represents an oxygen atom, a nitrogen atom or a direct bond.

Examples of the alkylene group having 1 to 5 carbon atoms for R ⁴ include a methylene group, an ethylene group, a propylene group (1,2-propylene group), a trimethylene group (1,3-propylene group), a tetramethylene group, and a pentamethylene group.
From the viewpoint of low temperature fixing property and hot offset resistance, R ^{4 is} preferably an alkylene group having 2 to 3 carbon atoms, and more preferably an alkylene group having 2 carbon atoms.
Furthermore, among X, from the viewpoints of hot offset resistance and charging stability, an oxygen atom is preferred.

Specific examples of the compound represented by formula (2) include (meth)acryloylmorpholine, 1-(meth)acryloylpyrrolidine, N-(meth)acryloylaziridine, N-(meth)acryloylazetidine, N-(meth)acryloylpiperidine, N-(meth)acryloylazepane, N-(meth)acryloylazocane, etc. Among these, from the viewpoints of low-temperature fixing ability and hot offset resistance, (meth)acryloylmorpholine is preferred.
In the present invention, "(meth)acryloyl" means "acryloyl" and/or "methacryloyl".

Examples of monomers (b) other than the compounds represented by general formula (1) and/or (2) include cinnamic acid amide and N,N-dibenzyl acrylamide.

The monomer composition (A0) containing the monomer (a) and the monomer (b) may be used in combination with other monomers as necessary, for example, a monomer (c) other than the monomers (a) and (b). The monomer (c) may be used alone or in combination of two or more kinds.
Examples of the monomer (c) include vinyl hydrocarbons (c1), carboxyl group-containing vinyl monomers (c2), hydroxyl group-containing vinyl monomers (c3), nitrogen-containing vinyl monomers (c4), epoxy group-containing vinyl monomers (c5), halogen element-containing vinyl monomers (c6), and other ester monomers (c7).

Examples of the vinyl hydrocarbon (c1) include aliphatic vinyl hydrocarbons, alicyclic vinyl hydrocarbons, and aromatic vinyl hydrocarbons.
Aliphatic vinyl hydrocarbons include alkenes and alkadienes.
Specific examples of alkenes include ethylene, propylene, butene, isobutylene, pentene, heptene, diisobutylene, octene, dodecene, octadecene, and α-olefins other than those mentioned above.
Specific examples of alkadienes include butadiene, isoprene, 1,4-pentadiene, 1,5-hexadiene, and 1,7-octadiene.
Alicyclic vinyl hydrocarbons include mono- or di-cycloalkenes and alkadienes, and specific examples thereof include cyclohexene, (di)cyclopentadiene, vinylcyclohexene, ethylidenebicycloheptene, and terpenes (pinene, limonene, indene, etc.).
Examples of aromatic vinyl hydrocarbons include styrene and its hydrocarbyl (alkyl, cycloalkyl, aralkyl and/or alkenyl) substituted products, and specific examples thereof include α-methylstyrene, vinyltoluene, 2,4-dimethylstyrene, ethylstyrene, isopropylstyrene, butylstyrene, phenylstyrene, cyclohexylstyrene, benzylstyrene, crotylbenzene, divinylbenzene, divinyltoluene, divinylxylene, trivinylbenzene, and vinylnaphthalene.

Examples of the carboxyl group-containing vinyl monomer (c2) include unsaturated monocarboxylic acids and unsaturated dicarboxylic acids having 3 to 20 carbon atoms, and anhydrides thereof.
Specific examples of the vinyl monomer include carboxyl group-containing vinyl monomers such as (meth)acrylic acid, (anhydride) maleic acid, maleic acid monoalkyl esters, fumaric acid, fumaric acid monoalkyl esters, crotonic acid, itaconic acid, itaconic acid monoalkyl esters, itaconic acid glycol monoether, citraconic acid, citraconic acid monoalkyl esters, and cinnamic acid.

Examples of hydroxyl group-containing vinyl monomers (c3) include hydroxystyrene, N-methylol (meth)acrylamide, hydroxyethyl (meth)acrylate (e.g., 2-hydroxyethyl acrylate, etc.), hydroxypropyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, (meth)allyl alcohol, crotyl alcohol, isocrotyl alcohol, 1-buten-3-ol, 2-buten-1-ol, 2-butene-1,4-diol, propargyl alcohol, 2-hydroxyethyl propenyl ether, and sucrose allyl ether.

Examples of the nitrogen-containing vinyl monomer (c4) include amino group-containing vinyl monomers, amide group-containing vinyl monomers, nitrile group-containing vinyl monomers, quaternary ammonium cation group-containing vinyl monomers, and nitro group-containing vinyl monomers.
Examples of the amino group-containing vinyl monomer include aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, t-butylaminoethyl methacrylate, N-aminoethyl (meth)acrylamide, (meth)allylamine, morpholinoethyl (meth)acrylate, 4-vinylpyridine, 2-vinylpyridine, crotylamine, N,N-dimethylaminostyrene, methyl α-acetaminoacrylate, vinylimidazole, N-vinylpyrrole, N-vinylthiopyrrolidone, N-arylphenylenediamine, aminocarbazole, aminothiazole, aminoindole, aminopyrrole, aminoimidazole, aminomercaptothiazole, and salts thereof.
The amide group-containing vinyl monomer includes those other than the monomer (b), such as (meth)acrylamide, N-methyl(meth)acrylamide, N-butylacrylamide, diacetone acrylamide, N-methylol(meth)acrylamide, N,N'-methylene-bis(meth)acrylamide, N,N-dimethylacrylamide, methacrylformamide, and N-methyl-N-vinylacetamide.
Examples of the nitrile group-containing vinyl monomer include acrylonitrile, methacrylonitrile, cyanostyrene, and cyanoacrylate.
Examples of the quaternary ammonium cation group-containing vinyl monomer include quaternized products of tertiary amine group-containing vinyl monomers such as dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylamide, diethylaminoethyl (meth)acrylamide, and diallylamine (which are quaternized using a quaternizing agent such as methyl chloride, dimethyl sulfate, benzyl chloride, and dimethyl carbonate).
Nitro group-containing vinyl monomers include nitrostyrene.

Examples of the epoxy group-containing vinyl monomer (c5) include glycidyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and p-vinylphenyl phenyl oxide.

Examples of halogen-containing vinyl monomers (c6) include vinyl chloride, vinyl bromide, vinylidene chloride, allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluorostyrene, and chloroprene.

Other ester monomers (c7) include, for example, alkyl (meth)acrylates having a chain hydrocarbon group and a carbon number of 20 or less, such as alkyl (meth)acrylates having an alkyl group with a carbon number of 1 to 17 [methyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, etc.], alkylene ether (meth)acrylates having a carbon number of 5 to 30 [methoxy-triethylene glycol (meth)acrylate, ethoxy-diethylene glycol (meth)acrylate, methoxy-polyethylene glycol (meth)acrylate, methoxydipropylene glycol (meth)acrylate, etc.], meth)acrylates, poly(meth)acrylates [poly(meth)acrylates of polyhydric alcohols such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and polyethylene glycol di(meth)acrylate, etc.], aliphatic vinyl esters having 4 to 15 carbon atoms and aromatic vinyl esters having 9 to 15 carbon atoms [vinyl acetate, vinyl butyrate, vinyl propionate, vinyl butyrate, and methyl-4-vinyl benzoate, etc.].

Among these monomers (c), vinyl hydrocarbons (c1), nitrogen-containing vinyl monomers (c4) and other ester monomers (c7) are preferred from the viewpoint of storage stability under high temperature and high humidity conditions, and aromatic vinyl hydrocarbons, nitrile group-containing vinyl monomers and alkyl (meth)acrylates having an alkyl group with 1 to 17 carbon atoms are more preferred.

The weight proportion of monomer (a) in monomer composition (A0) in crystalline vinyl resin (A) is 40 to 90% by weight, preferably 50 to 90% by weight, more preferably 50 to 70% by weight, and even more preferably 50 to 60% by weight, based on the weight of monomer composition (A0). If the weight proportion of monomer (a) is less than 40% by weight, low-temperature fixing properties deteriorate. On the other hand, if the weight proportion of monomer (a) exceeds 90% by weight, hot offset resistance deteriorates.

From the viewpoints of storage stability and hydrolysis resistance under high temperature and high humidity conditions, the weight ratio of monomer (b) in monomer composition (A0) in crystalline vinyl resin (A) is preferably 1 to 35% by weight, more preferably 5 to 30% by weight, and even more preferably 5 to 15% by weight, based on the weight of monomer composition (A0).

When monomer composition (A0) contains monomer (c), from the viewpoint of hot offset resistance, the weight ratio of monomer (c) in monomer composition (A0) is preferably 4 to 55% by weight, more preferably 10 to 55% by weight, and even more preferably 10 to 45% by weight.

The crystalline vinyl resin (A) in the present invention can be produced by polymerizing a monomer composition by a known method (e.g., radical polymerization, anionic polymerization, cationic polymerization, living radical polymerization, living anionic polymerization, living cationic polymerization, etc.). In the case of radical polymerization, for example, the resin can be synthesized by a solution polymerization method (JP Patent Publication (A) No. 5-117330, etc.) in which the monomer is reacted with a radical reaction initiator (d) in a solvent (e.g., toluene).
The radical reaction initiator may be a known radical reaction initiator (d). The radical reaction initiator (d) is not particularly limited, and examples thereof include inorganic peroxides (d1), organic peroxides (d2), and azo compounds (d3). These radical reaction initiators may also be used in combination.

The inorganic peroxide (d1) is not particularly limited, but examples thereof include hydrogen peroxide, ammonium persulfate, potassium persulfate, and sodium persulfate.

The organic peroxide (d2) is not particularly limited, but examples thereof include benzoyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, α,α-bis(t-butylperoxy)diisopropylbenzene, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, di-t-hexyl peroxide, 2,5-dimethyl-2,5-di-t-butylperoxyhexyne-3, acetyl peroxide, isobutyryl peroxide, octanyl peroxide, decanolyl peroxide, Examples include lauroyl peroxide, 3,3,5-trimethylhexanoyl peroxide, m-toluyl peroxide, t-butyl peroxy isobutyrate, t-butyl peroxy neodecanoate, cumyl peroxy neodecanoate, t-butyl peroxy 2-ethylhexanoate, t-butyl peroxy 3,5,5-trimethylhexanoate, t-butyl peroxy laurate, t-butyl peroxy benzoate, t-butyl peroxy isopropyl monocarbonate, and t-butyl peroxy acetate.

The azo compound (d3) is not particularly limited, but examples thereof include 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, 2,2'-azobis(2-methylbutyronitrile), and azobisisobutyronitrile.

The endothermic peak top temperature (Tm _A ) of the crystalline vinyl resin (A) is preferably 40 to 100° C., more preferably 45 to 90° C., and even more preferably 50 to 60° C., from the viewpoint of low-temperature fixability and storage stability under high-temperature and high-humidity conditions. When the endothermic peak top temperature is 40° C. or higher, the storage stability under high-temperature and high-humidity conditions is good, and when it is 100° C. or lower, the low-temperature fixability is good. The endothermic peak top temperature (Tm _A ) can be adjusted mainly by the number of parts by weight of the monomer (a) and the number of carbon atoms of the chain hydrocarbon group of the monomer (a). When the number of parts by weight of the monomer (a) is large, the peak top temperature (Tm _A ) can be increased, and when the number of carbon atoms of the chain hydrocarbon group of the monomer (a) is large, the peak top temperature (Tm _A ) can be increased.
Here, the endothermic peak top temperature (Tm _A ) of the crystalline vinyl resin (A) refers to the peak top temperature of the endothermic peak of the crystalline vinyl resin (A) in a second heating process in which the crystalline vinyl resin (A) is heated for the first time from 20° C. to 150° C. at 10° C./min using a differential scanning calorimeter (DSC), then cooled from 150° C. to 0° C. at 10° C./min, and subsequently heated from 0° C. to 150° C. at 10° C./min.

The xylene insoluble content of the crystalline vinyl resin (A) is preferably 6% by weight or less, more preferably 1 to 3% by weight, from the viewpoints of low-temperature fixability, storage stability under high-temperature and high-humidity conditions, and hydrolysis resistance. The xylene insoluble content can be adjusted by the number of parts by weight of the monomer (b). The higher the number of parts by weight of the monomer (b), the higher the xylene insoluble content.
The xylene-insoluble content of the crystalline vinyl resin (A) is measured by the following method.
To prepare a sample, 1.00 g of crystalline vinyl resin (A) was dissolved or dispersed in 100 g of xylene at a temperature equal to or higher than the peak top temperature of the endothermic peak, cooled to 25°C, centrifuged in a centrifuge, the supernatant was removed, and then dried under reduced pressure (170°C, 2 hours) to obtain a xylene-insoluble matter. The weight of the xylene-insoluble matter was measured to four decimal places, and the xylene-insoluble matter of (A) was calculated using the following formula.
Xylene insoluble content (wt%) of crystalline vinyl resin (A)=(weight of xylene insoluble content (g)/1.00)×100
The conditions for centrifugation are as follows:
<Centrifugation conditions>
Centrifuge: H-19F (manufactured by Kokusan Co., Ltd.)
Rotation speed: 4000 rpm
Rotation time: 20 minutes

The weight average molecular weight of the crystalline vinyl resin (A) in the present invention, as measured by gel permeation chromatography (GPC), is preferably 2,000 to 200,000, more preferably 5,000 to 100,000, even more preferably 10,000 to 70,000, and particularly preferably 20,000 to 40,000, from the viewpoints of low-temperature fixability and hot offset resistance.

In the present invention, the number average molecular weight (hereinafter sometimes abbreviated as Mn) and weight average molecular weight (hereinafter sometimes abbreviated as Mw) of the crystalline vinyl resin (A) and the resin for toner binder other than (A) described below can be measured using GPC under the following conditions.
Equipment (example): HLC-8120 [manufactured by Tosoh Corporation]
Column (example): 2 TSK GEL GMH6 columns [manufactured by Tosoh Corporation]
Measurement temperature: 40°C
Sample solution: 0.25% by weight THF solution Mobile phase: Tetrahydrofuran (containing no polymerization inhibitor)
Solution injection volume: 100 μL
Detector: Refractive index detector Reference material: 12 standard polystyrenes (TSKstandard POLYSTYRENE) (molecular weights: 500, 1,050, 2,800, 5,970, 9,100, 18,100, 37,900, 96,400, 190,000, 355,000, 1,090,000, 2,890,000) [manufactured by Tosoh Corporation]
For measuring the molecular weight, a sample is dissolved in tetrahydrofuran (hereinafter abbreviated as THF) to a concentration of 0.25% by weight, and the insoluble matter is filtered off using a glass filter to obtain a sample solution.
Incidentally, for the amorphous vinyl resin (B) and the toner binder described below, Mn and Mw can be determined in the same manner as above.

The toner binder of the present invention may contain other resins known as toner binder resins other than the crystalline vinyl resin (A). Examples of other resins include vinyl resins, polyurethane resins, epoxy resins, polyester resins, polyamide resins, polyimide resins, ionomer resins, polycarbonate resins, etc., and two or more of the above resins may be used in combination. These resins may be either linear or nonlinear resins, and nonlinear resins may be crosslinked. Among these, from the viewpoint of low-temperature fixing property and hydrolysis resistance, vinyl resins and polyester resins are preferred, and amorphous vinyl resins (B) and nonlinear polyester resins (C) are particularly preferred.

The composition of the amorphous vinyl resin (B) is not particularly limited as long as it is an amorphous vinyl resin. From the viewpoints of storage stability and hydrolysis resistance under high temperature and high humidity conditions, however, it is preferable that the resin be a polymer of a monomer composition (B0) containing styrene.
In the present invention, "amorphous" means that when the transition temperature of a sample is measured using a differential scanning calorimeter (DSC) under the same measurement conditions as in the measurement method for the peak top temperature of the endothermic peak of the above-mentioned crystalline vinyl resin (A), no peak top temperature of the endothermic peak exists.

The styrene-containing monomer composition (B0) may be used in combination with other monomers as necessary, and examples thereof include the same monomers as those exemplified as the monomer (c) in the crystalline vinyl resin (A). These monomers may be used alone or in combination of two or more, and examples thereof include styrene-alkyl (meth)acrylate copolymers, styrene-(meth)acrylic acid copolymers, styrene-alkyl (meth)acrylate-(meth)acrylic acid copolymers, styrene-acrylonitrile copolymers, styrene-maleic anhydride copolymers, and styrene-alkyl (meth)acrylate-acrylonitrile copolymers.
Of the above, preferred are styrene-alkyl (meth)acrylate copolymers, styrene-(meth)acrylic acid copolymers, styrene-alkyl (meth)acrylate-(meth)acrylic acid copolymers, styrene-acrylonitrile copolymers, and styrene-alkyl (meth)acrylate-acrylonitrile copolymers, and more preferred are styrene-alkyl (meth)acrylate-(meth)acrylic acid copolymers, and styrene-alkyl (meth)acrylate-acrylonitrile copolymers.

The acid value of the amorphous vinyl resin (B) is preferably 0 to 50 mgKOH/g, more preferably 0.1 to 30 mgKOH/g, from the viewpoints of low-temperature fixability, storage stability under high-temperature and high-humidity conditions, and hydrolysis resistance.
The acid value can be measured by the method specified in JIS K0070.

The glass transition temperature of the amorphous vinyl resin (B) is preferably 50 to 75°C, more preferably 55 to 70°C, from the viewpoints of storage stability under high temperature and high humidity conditions and low temperature fixability.
The glass transition temperature (Tg) of the amorphous vinyl resin (B) can be determined by the method (DSC method) specified in ASTM D3418-82. For example, a DSC Q20 manufactured by TA Instruments Co., Ltd. can be used to measure the glass transition temperature (Tg). The glass transition temperature (Tg) can be measured under the following conditions.
<Measurement conditions>
(1) Heat from 30°C to 150°C at 20°C/min. (2) Hold at 150°C for 10 minutes. (3) Cool to -35°C at 20°C/min. (4) Hold at -35°C for 10 minutes. (5) Heat to 150°C at 20°C/min. (6) The differential scanning calorimetry curve measured during (5) is analyzed, and the position of the inflection point is determined as the glass transition temperature.

The amorphous vinyl resin (B) in the present invention can be produced in the same manner as the crystalline vinyl resin (A). The radical reaction initiator (d) in the case of radical polymerization can also be the same.

The composition of the nonlinear polyester resin (C) is not particularly limited as long as it is a nonlinear polyester resin. The nonlinear polyester resin (C) is a polyester resin obtained by polycondensation of an alcohol component including a polyol component (x) and a carboxylic acid component including a polycarboxylic acid component (y), and may be crosslinked.

The polyol component (x) may be a diol (x1) or a trihydric or higher polyol (x2). These may be used alone or in combination of two or more.

Diols (x1) include alkylene glycols having 2 to 36 carbon atoms (ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, etc.), alkylene ether glycols having 4 to 36 carbon atoms (diethylene glycol, triethylene glycol, etc.), , dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.), alicyclic diols having 6 to 36 carbon atoms (1,4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.), (poly)alkylene oxide adducts of the above alicyclic diols (preferably 1 to 30 average molar additions), aromatic diols [monocyclic dihydric phenols (e.g., hydroquinone, etc.) and bisphenols, etc.] and alkylene oxide adducts of the above aromatic diols (preferably 2 to 30 average molar additions), etc.

The alkylene oxide adducts of the above bisphenols are obtained by adding alkylene oxide (hereinafter, "alkylene oxide" may be abbreviated as AO) to bisphenols.

The bisphenols include those represented by the following general formula (1).
HO-Ar-P-Ar-OH (1)
[In the formula, P represents an alkylene group having 1 to 3 carbon atoms, -SO ₂ -, -O-, -S- or a direct bond, and Ar represents a phenylene group in which a hydrogen atom may be substituted with a halogen atom or an alkyl group having 1 to 30 carbon atoms.]

Specific examples of bisphenols include bisphenol A, bisphenol F, bisphenol B, bisphenol AD, bisphenol S, trichlorobisphenol A, tetrachlorobisphenol A, dibromobisphenol F, 2-methylbisphenol A, 2,6-dimethylbisphenol A, and 2,2'-diethylbisphenol F, and two or more of these can be used in combination.

Examples of alkylene oxides added to bisphenols include alkylene oxides having 2 to 30 carbon atoms, such as ethylene oxide (hereinafter, "ethylene oxide" may be abbreviated as EO), propylene oxide (hereinafter, "propylene oxide" may be abbreviated as PO), butylene oxide, tetrahydrofuran, and combinations of two or more of these.

Among these diols (x1), from the viewpoint of low-temperature fixability and storage stability under high-temperature and high-humidity conditions, alkylene glycols having 2 to 36 carbon atoms and alkylene oxide adducts of aromatic diols are preferred, alkylene glycols having 2 to 10 carbon atoms and alkylene oxide adducts of bisphenols (average number of moles added is preferably 2 to 5), and alkylene glycols having 2 to 6 carbon atoms and alkylene oxide adducts of bisphenol A (average number of moles added is preferably 2 to 5) are even more preferred.

Examples of trivalent or higher polyols (x2) include aliphatic polyhydric alcohols having 3 to 36 carbon atoms and a valence of trivalent or higher, sugars and derivatives thereof, alkylene oxide adducts of aliphatic polyhydric alcohols (average number of moles added is preferably 1 to 30), alkylene oxide adducts of trisphenols (trisphenol PA, etc.) (average number of moles added is preferably 2 to 30), and alkylene oxide adducts of novolac resins (including phenol novolac and cresol novolac, etc., with an average degree of polymerization of preferably 3 to 60) (average number of moles added is preferably 2 to 30).

Examples of the aliphatic polyhydric alcohol having 3 to 36 carbon atoms and a valence of three or more include alkane polyols and their intramolecular or intermolecular dehydration products, such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, sorbitan, polyglycerin, and dipentaerythritol.
Furthermore, examples of sugars and their derivatives include sucrose and methyl glucoside.

Of these trivalent or higher polyols (x2), from the viewpoint of achieving both low-temperature fixing properties and hot offset resistance, preferred are trivalent or higher aliphatic polyhydric alcohols having 3 to 36 carbon atoms, and alkylene oxide adducts (average number of moles added is preferably 2 to 30) of novolak resins (including phenol novolak and cresol novolak, etc., with an average degree of polymerization preferably being 3 to 60), more preferred are trivalent aliphatic polyhydric alcohols having 3 to 8 carbon atoms, and particularly preferred is trimethylolpropane.

The diol (x1) in the polyol component (x) of the nonlinear polyester resin (C) is preferably 80 to 100 mol %. When the diol (x1) is used in combination with a trihydric or higher polyol (x2), the molar ratio of the diol (x1) to the trihydric or higher polyol (x2) [(x1)/(x2)] is preferably 80/20 to 99/1, more preferably 85/15 to 98/2, from the viewpoint of hot offset resistance.

In addition to the polyol component (x), the alcohol component of the nonlinear polyester resin (C) may contain a mono-ol component, if necessary. Examples of mono-ols include linear or branched alkyl alcohols having 1 to 30 carbon atoms (methanol, ethanol, isopropanol, 1-decanol, dodecyl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, arachidyl alcohol, behenyl alcohol, and lignoceryl alcohol).

Of these monools, from the viewpoint of storage stability under high temperature and high humidity conditions, linear or branched alkyl alcohols having 8 to 24 carbon atoms are preferred, linear alkyl alcohols having 8 to 24 carbon atoms are more preferred, and dodecyl alcohol, stearyl alcohol, arachidyl alcohol, behenyl alcohol and lignoceryl alcohol are even more preferred.

The polycarboxylic acid component (y) may be a dicarboxylic acid (y1) or a trivalent or higher polycarboxylic acid (y2). These may be used alone or in combination of two or more.

Examples of dicarboxylic acids (y1) include aromatic dicarboxylic acids having 8 to 36 carbon atoms (such as terephthalic acid, phthalic acid, isophthalic acid, and naphthalenedicarboxylic acid), aliphatic dicarboxylic acids having 2 to 50 carbon atoms (such as oxalic acid, malonic acid, succinic acid, adipic acid, leuparic acid, and sebacic acid), alicyclic dicarboxylic acids having 6 to 40 carbon atoms (such as dimer acid (dimerized linoleic acid)), alkene dicarboxylic acids having 4 to 36 carbon atoms (such as alkenyl succinic acids such as dodecenyl succinic acid, maleic acid, fumaric acid, citraconic acid, and mesaconic acid), and ester-forming derivatives thereof. Here, the ester-forming derivatives refer to carboxylic acid anhydrides, alkyl (methyl, ethyl, butyl, stearyl, and the like having 1 to 24 carbon atoms, preferably alkyl having 1 to 4 carbon atoms) esters, and partial alkyl esters.

Among these dicarboxylic acids (y1), from the viewpoint of achieving both low-temperature fixability, hot offset resistance, and storage stability under high temperature and high humidity, aromatic dicarboxylic acids having 8 to 36 carbon atoms, aliphatic dicarboxylic acids having 2 to 50 carbon atoms, and alkene dicarboxylic acids having 4 to 36 carbon atoms are preferred, with terephthalic acid, phthalic acid, isophthalic acid, adipic acid, succinic acid, maleic acid, and fumaric acid being more preferred, with terephthalic acid, phthalic acid, isophthalic acid, adipic acid, and fumaric acid being even more preferred, and terephthalic acid, isophthalic acid, adipic acid, and fumaric acid being particularly preferred. In addition, anhydrides or lower alkyl esters of these acids may also be used.

Examples of trivalent or higher polycarboxylic acids (y2) include trivalent or higher aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid), aliphatic (including alicyclic) tricarboxylic acids having 6 to 36 carbon atoms (such as hexanetricarboxylic acid and decanetricarboxylic acid), and ester-forming derivatives thereof.

Among these trivalent or higher polycarboxylic acids (y2), from the viewpoint of achieving both low-temperature fixability and hot offset resistance, aromatic polycarboxylic acids having 9 to 20 carbon atoms are preferred, and trimellitic acid and pyromellitic acid are more preferred. In addition, anhydrides or lower alkyl esters of these acids may also be used.

The total proportion of terephthalic acid and isophthalic acid in the polycarboxylic acid component of the nonlinear polyester resin (C) may be 80 to 100 mol %, or may be 100 mol %. In other words, the nonlinear polyester resin (C) may not contain any carboxylic acid components other than terephthalic acid and isophthalic acid as polycarboxylic acid components.

In addition, the nonlinear polyester resin (C) may contain a monocarboxylic acid component as a carboxylic acid component, if necessary. Examples of monocarboxylic acids include aromatic monocarboxylic acids having 7 to 37 carbon atoms (benzoic acid, toluic acid, 4-ethylbenzoic acid, 4-propylbenzoic acid, etc.), and aliphatic (including alicyclic) monocarboxylic acids having 2 to 50 carbon atoms (acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, behenic acid, etc.).

Of these monocarboxylic acids, from the viewpoint of storage stability under high temperature and high humidity conditions, aliphatic (including alicyclic) monocarboxylic acids having 2 to 50 carbon atoms are preferred, and behenic acid is more preferred.

From the viewpoints of low-temperature fixability and storage stability under high-temperature and high-humidity conditions, the weight-average molecular weight of the nonlinear polyester resin (C) is preferably 3,000 to 10,000, and more preferably 5,000 to 9,000.

The acid value of the nonlinear polyester resin (C) is preferably 0 to 50 mgKOH/g, more preferably 0.1 to 30 mgKOH/g, from the viewpoints of low-temperature fixability, storage stability under high-temperature and high-humidity conditions, and hydrolysis resistance.
The acid value can be measured by the method specified in JIS K0070.

The glass transition temperature of the nonlinear polyester resin (C) is preferably 43 to 60° C., more preferably 48 to 55° C., from the viewpoints of storage stability under high temperature and high humidity conditions and low temperature fixability.
The glass transition temperature of the nonlinear polyester resin (C) can be measured by the same method as the above-mentioned method for measuring the glass transition temperature of the amorphous vinyl resin (B).

Specifically, the nonlinear polyester resin (C) can be produced, for example, as follows: For example, an alcohol component and a carboxylic acid component are subjected to a polycondensation reaction in an inert gas (such as nitrogen gas) atmosphere at a reaction temperature of preferably 150 to 280°C, more preferably 160 to 250°C, and even more preferably 170 to 235°C.
From the viewpoint of ensuring the polycondensation reaction, the reaction time is preferably 30 minutes or more, more preferably 2 to 40 hours. It is also effective to reduce the pressure in order to improve the reaction rate at the end of the reaction.

In this case, an esterification catalyst can be used as necessary.
Examples of the esterification catalyst include tin-containing catalysts (e.g., dibutyltin oxide, etc.), antimony trioxide, titanium-containing catalysts [e.g., titanium alkoxides (tetrabutoxytitanate, etc.), potassium oxalate titanate, titanium terephthalate, titanium alkoxide terephthalate, catalysts described in JP-A-2006-243715 {titanium diisopropoxybis(triethanolaminate), titanium dihydroxybis(triethanolaminate), titanium monohydroxytris(triethanolaminate), titanyl bis(triethanolaminate) and intramolecular polycondensates thereof, etc.} and catalysts described in JP-A-2007-11307 (titanium tributoxyterephthalate, titanium triisopropoxyterephthalate, titanium diisopropoxyditerephthalate, etc.)], zirconium-containing catalysts (e.g., zirconyl acetate, etc.), and zinc acetate. Among these, titanium-containing catalysts are preferred.

A stabilizer may be added to facilitate stable polymerization of the polyester. Examples of stabilizers include hydroquinone, methylhydroquinone, and hindered phenol compounds.

When the nonlinear polyester resin (C) is crosslinked, the following method is preferable as a method for producing the nonlinear polyester resin (C).
First, at least one of an unsaturated carboxylic acid component and an unsaturated alcohol component is condensed with a saturated carboxylic acid component and/or a saturated alcohol component as necessary to obtain a polyester resin (C0) having a carbon-carbon double bond in the molecule. Next, a radical reaction initiator is allowed to act on (C0), and the carbon-carbon double bonds resulting from the unsaturated carboxylic acid component and/or the unsaturated alcohol component are bonded to each other by a crosslinking reaction using radicals generated from the radical reaction initiator. This makes it possible to produce a nonlinear polyester resin (C). This method is preferred because it allows the crosslinking reaction to occur uniformly in a short time.
Among the unsaturated carboxylic acid components, from the viewpoint of achieving both low-temperature fixability and heat-resistant storage stability, preferred are unsaturated monocarboxylic acids having 2 to 10 carbon atoms and alkene dicarboxylic acids having 4 to 18 carbon atoms, more preferred are acrylic acid, methacrylic acid, alkenylsuccinic acids such as dodecenylsuccinic acid, maleic acid and fumaric acid, and even more preferred are acrylic acid, methacrylic acid, maleic acid, fumaric acid and combinations of these. Similarly, anhydrides and lower alkyl esters of these acids are also preferred.
The unsaturated alcohol component may include unsaturated monools and unsaturated diols. Examples of the unsaturated monools include 2-propen-1-ol and 2-hydroxyethyl methacrylate. Examples of the unsaturated diols include ricinoleyl alcohol. These may be used alone or in combination of two or more.

The radical reaction initiator (c) used for the crosslinking reaction of the polyester resin (C0) having a carbon-carbon double bond is not particularly limited, and examples thereof include the inorganic peroxides, organic peroxides, and azo compounds described above. These radical reaction initiators (c) may be used alone or in combination of two or more.

The amount of the radical reaction initiator (c) used is not particularly limited, but is preferably 0.1 to 50 parts by weight per 100 parts by weight based on the total weight of the unsaturated carboxylic acid component and the unsaturated alcohol component used in the polymerization reaction for obtaining the polyester resin (C0) having a carbon-carbon double bond.
When the amount of the radical reaction initiator used is 0.1 parts by weight or more, the crosslinking reaction tends to proceed easily, and when it is 50 parts by weight or less, the odor tends to be good. The amount used is more preferably 30 parts by weight or less, even more preferably 20 parts by weight or less, and particularly preferably 10 parts by weight or less.
When polyester (A1) is polyester (A11) having a carbon-carbon double bond, the content of the carbon-carbon double bond in polyester (A11) is not particularly limited, but is preferably 0.1 to 1.2 mmol/g, more preferably 0.1 to 0.9 mmol/g, based on the weight of polyester (A11). When the content of the carbon-carbon double bond is 0.1 to 1.2 mmol/g based on the weight of polyester (A11), a crosslinking reaction occurs favorably, and the toner has good storage stability under high temperature and high humidity conditions.

When the nonlinear polyester resin (C) is produced by radical polymerization using the above-mentioned type of radical reaction initiator (c) in the above-mentioned amount, a crosslinking reaction occurs between the carbon-carbon double bonds in the polyester resin (C0), which is preferable because it improves the toner's low-temperature fixability, hot offset resistance, and storage stability under high temperature and high humidity conditions.

In the present invention, the weight ratio of the crystalline vinyl resin (A) is preferably 10 to 60% by weight based on the weight of the toner binder, from the viewpoints of low-temperature fixing property, hot offset resistance, and storage stability under high temperature and high humidity conditions.

In the present invention, when other resins such as amorphous vinyl resin (B) and nonlinear polyester resin (C) are contained, the content of the other resins is preferably 40 to 90% by weight based on the weight of the toner binder, from the viewpoints of low-temperature fixing property, hot offset resistance, and storage stability under high temperature and high humidity conditions.

A method for producing the toner binder will now be described.
The toner binder is not particularly limited as long as it contains the crystalline vinyl resin (A), and for example, the mixing method for mixing the crystalline vinyl resin (A), other resins and additives used as necessary may be a known method, and examples of the mixing method include powder mixing, melt mixing, solvent mixing, etc. In addition, the crystalline vinyl resin (A), other resins and additives used as necessary may be mixed simultaneously when the toner is produced.

Examples of a mixer for powder mixing include a Henschel mixer, a Nauta mixer, and a Banbury mixer, with a Henschel mixer being preferred.
Examples of mixing devices for melt mixing include batch mixing devices such as reaction tanks and continuous mixing devices. Continuous mixing devices are preferred for uniform mixing in a short time at an appropriate temperature. Examples of continuous mixing devices include static mixers, extruders, continuous kneaders, and three-roll machines.
Examples of the solvent mixing method include a method in which the crystalline vinyl resin (A) and other resins are dissolved in a solvent (ethyl acetate, THF, acetone, etc.), homogenized, then desolvated and pulverized, and a method in which the crystalline vinyl resin (A) and other resins are dissolved in a solvent (ethyl acetate, THF, acetone, etc.), dispersed in water, then granulated and desolvated.

The toner binder of the present invention is useful when applied to a toner. The toner contains the toner binder of the present invention.

In addition to the toner binder of the present invention, the toner may contain, as necessary, one or more known additives selected from colorants, release agents, charge control agents, and flow agents.

As the colorant, all of the dyes and pigments used as toner colorants can be used. For example, carbon black, iron black, Sudan Black SM, Fast Yellow G, Benzidine Yellow, Pigment Yellow, India Fast Orange, Irgasin Red, Paranitroaniline Red, Toluidine Red, Carmine FB, Pigment Orange R, Lake Red 2G, Rhodamine FB, Rhodamine B Lake, Methyl Violet B Lake, Phthalocyanine Blue, Pigment Blue, Brilliant Green, Phthalocyanine Green, Oil Yellow GG, Kayaset YG, Orazol Brown B, and Oil Pink OP can be mentioned. The colorant may be any one of these alone or a mixture of two or more. In addition, if necessary, magnetic powder (powder of ferromagnetic metals such as iron, cobalt, and nickel, or compounds such as magnetite, hematite, and ferrite) can be contained to function as a colorant.
The content of the colorant is preferably 1 to 40 parts by weight, more preferably 3 to 10 parts by weight, based on 100 parts by weight of the toner binder. When a magnetic powder is used, the content is preferably 20 to 150 parts by weight, more preferably 40 to 120 parts by weight, based on 100 parts by weight of the toner binder.

The release agent preferably has a flow softening point (T1 _/2 ) of 50 to 170°C as measured by a constant test force extrusion type capillary rheometer flow tester. Examples of the release agent include aliphatic hydrocarbon waxes such as polyolefin wax, microcrystalline wax, paraffin wax, and Fischer-Tropsch wax, as well as oxides thereof, carnauba wax, montan wax and deacidified waxes thereof, ester wax, fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts.

The flow softening point (T _1/2 ) of the release agent is a value measured under the following conditions.
<Method of measuring flow softening point (T _1/2 )>
Test force: Using an extrusion-type capillary rheometer flow tester [e.g., CFT-500D, manufactured by Shimadzu Corporation], 1 g of the measurement sample is heated at a temperature increase rate of 6°C/min while applying a load of 1.96 MPa with the plunger and extruding it from a nozzle with a diameter of 1 mm and a length of 1 mm. A graph of "plunger depression amount (flow value)" vs. "temperature" is drawn, and the temperature corresponding to 1/2 of the maximum plunger depression amount is read from the graph. This value (the temperature at which half of the measurement sample has flowed out) is taken as the flow softening point (T _1/2 ).

Examples of polyolefin waxes include (co)polymers of olefins (e.g., ethylene, propylene, 1-butene, isobutylene, 1-hexene, 1-dodecene, 1-octadecene, and mixtures thereof) (including those obtained by (co)polymerization and those obtained by further thermal degradation) (e.g., low molecular weight polypropylene, low molecular weight polyethylene, low molecular weight polypropylene-polyethylene copolymers), oxides of olefin (co)polymers with oxygen and/or ozone, maleic acid modified products of olefin (co)polymers (e.g., maleic acid and its derivatives (maleic anhydride, monomethyl maleate, monobutyl maleate, dimethyl maleate, etc.) modified products), copolymers of olefins and unsaturated carboxylic acids ((meth)acrylic acid, itaconic acid, maleic anhydride, etc.) and/or unsaturated carboxylic acid alkyl esters ((meth)acrylic acid alkyl esters (alkyl having 1 to 18 carbon atoms) and maleic acid alkyl esters (alkyl having 1 to 18 carbon atoms), etc.).

Examples of microcrystalline waxes include Hi-Mic-2095, Hi-Mic-1090, Hi-Mic-1080, Hi-Mic-1070, Hi-Mic-2065, Hi-Mic-1045, and Hi-Mic-2045 manufactured by Nippon Seiro Co., Ltd.

Examples of paraffin waxes include Paraffin WAX-155, Paraffin WAX-150, Paraffin WAX-145, Paraffin WAX-140, Paraffin WAX-135, HNP-3, HNP-5, HNP-9, HNP-10, HNP-11, HNP-12, and HNP-51 manufactured by Nippon Seiro Co., Ltd.

Examples of Fischer-Tropsch wax include Sasolwax C80 manufactured by Sasol.

Examples of carnauba wax include Refined Carnauba Wax Special No. 1 manufactured by Kato Yoko Co., Ltd.

Examples of ester waxes include fatty acid ester waxes (e.g., Nissan Electol WEP-2, WEP-3, WEP-4, WEP-5, and WEP-8 manufactured by NOF Corp.).

Examples of higher alcohols include aliphatic alcohols having 30 to 50 carbon atoms, such as triacontanol. Examples of fatty acids include fatty acids having 30 to 50 carbon atoms, such as triacontanol.

Examples of fatty acid amides include Diamid Y and Diamid 200 manufactured by Mitsubishi Chemical Corporation.

The charge control agent may be either a positively charged charge control agent or a negatively charged charge control agent, and examples of the charge control agent include nigrosine dyes, triphenylmethane dyes containing a tertiary amine as a side chain, quaternary ammonium salts, polyamine resins, imidazole derivatives, polymers containing quaternary ammonium bases, metal-containing azo dyes, copper phthalocyanine dyes, metal salts of salicylic acid, boron complexes of benzilic acid, polymers containing sulfonic acid groups, fluorine-containing polymers, and polymers containing halogen-substituted aromatic rings.

Examples of fluidizing agents include silica, titania, alumina, calcium carbonate, fatty acid metal salts, silicone resin particles, and fluororesin particles, and two or more of them may be used in combination. From the viewpoint of the chargeability of the toner, silica is preferred. From the viewpoint of the transferability of the toner, it is also preferred that the silica is hydrophobic.

The content of the toner binder in the toner is preferably from 30 to 97% by weight, more preferably from 40 to 95% by weight, and even more preferably from 45 to 92% by weight, based on the weight of the toner.
The content of the colorant is preferably 0.05 to 60% by weight, more preferably 0.1 to 55% by weight, and even more preferably 0.5 to 50% by weight, based on the weight of the toner.
The content of the releasing agent is preferably 0 to 30% by weight, more preferably 0.5 to 20% by weight, and further preferably 1 to 10% by weight, based on the weight of the toner.
The content of the charge control agent is preferably 0 to 20% by weight, more preferably 0.1 to 10% by weight, and even more preferably 0.5 to 7.5% by weight, based on the weight of the toner.
The content of the fluidizing agent is preferably 0 to 10% by weight, more preferably 0 to 5% by weight, and further preferably 0.1 to 4% by weight, based on the weight of the toner.
The total content of the additives is preferably 3 to 70% by weight, more preferably 5 to 60% by weight, and even more preferably 8 to 55% by weight, based on the weight of the toner.
By setting the composition ratio of the toner in the above range, it is possible to easily obtain a toner having good charge stability while simultaneously achieving both low-temperature fixability and high separability from the fixing roller.

The toner may be obtained by any of the known methods such as a kneading and pulverizing method, an emulsion phase inversion method, and a polymerization method.
For example, when a toner is obtained by a kneading and pulverizing method, the components constituting the toner except for the fluidizing agent are dry-blended, melt-kneaded, coarsely pulverized, and finally, pulverized into fine particles using a jet mill pulverizer or the like, and further classified to obtain fine particles having a volume average particle size (D50) of preferably 5 to 20 μm, and then the fluidizing agent is mixed therein to produce the toner.
The volume average particle size (D50) is measured using a Coulter counter (for example, trade name: Multisizer III [manufactured by Beckman Coulter, Inc.]).

When obtaining toner by the emulsion phase inversion method, the components constituting the toner, excluding the fluidizing agent, are dissolved or dispersed in an organic solvent, and then emulsified by adding water, etc., and then separated and classified to produce the toner. The volume average particle size of the toner is preferably 3 to 15 μm.

The toner is mixed with carrier particles such as iron powder, glass beads, nickel powder, ferrite, magnetite, and ferrite coated with resin (acrylic resin, silicone resin, etc.) as necessary, and used as a developer for an electric latent image. When carrier particles are used, the weight ratio of the toner to the carrier particles is preferably 1/99 to 99/1. Alternatively, the toner can be rubbed against a member such as a charging blade instead of the carrier particles to form an electric latent image.
The toner does not necessarily need to contain carrier particles.

The toner is fixed to a support (paper, polyester film, etc.) by a copier, printer, etc. to form a recording material. The method of fixing to the support can be a known hot roll fixing method or flash fixing method, etc.

The toner produced using the toner binder of the present invention is used for developing electrostatic images or magnetic latent images in electrophotography, electrostatic recording, electrostatic printing, etc. More specifically, it is used for developing electrostatic images or magnetic latent images that are particularly suitable for full color.

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these. In the following, "parts" refers to parts by weight unless otherwise specified.

<Production Example 1> [Production of Crystalline Vinyl Resin (A1)]
110 parts of xylene was charged into an autoclave, and after replacing with nitrogen, the temperature was raised to 167°C in a sealed state with stirring. A mixed solution of 435 parts of behenyl acrylate [abbreviated as C22 acrylate hereinafter, manufactured by NOF Corp., the same applies below], 109 parts of N-vinylpyrrolidone [manufactured by Nippon Shokubai Co., Ltd., the same applies below], 36 parts of styrene [manufactured by Idemitsu Kosan Co., Ltd., the same applies below], 73 parts of methyl acrylate [manufactured by Toagosei Co., Ltd., the same applies below], 113 parts of methacrylonitrile [manufactured by Nacalai Tesque Inc., the same applies below], 0.7 parts of di-t-butyl peroxide [Perbutyl D, manufactured by NOF Corp., the same applies below], and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 167°C, to carry out polymerization. After dropping, the dropping line was washed with 8 parts of xylene. After further maintaining the temperature for 0.7 hours, the reaction rate of the monomer (a) was confirmed after cooling to 70°C. Since the reaction rate of the monomer (a) was less than 95%, the temperature was raised again to 170°C, and 1.1 parts of di-t-butyl peroxide was further added to react until the reaction rate reached 95% or more. Thereafter, the solvent was removed at 170°C under reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain a crystalline vinyl resin (A1).
The weight average molecular weight of the crystalline vinyl resin (A1) measured by the above-mentioned method was 30,000, the endothermic peak top temperature was 58° C., and the xylene insoluble content was 1% by weight.

<Production Example 2> [Production of Crystalline Vinyl Resin (A2)]
120 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 170 ° C. in a sealed state under stirring. A mixed solution of 420 parts of C22 acrylate, 105 parts of acryloyl morpholine [manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., the same applies below], 35 parts of styrene, 56 parts of methyl acrylate, 84 parts of methacrylonitrile, 0.7 parts of di-t-butyl peroxide, and 156 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 170 ° C. to polymerize. After dropping, the dropping line was washed with 9 parts of xylene. After further holding at the same temperature for 0.5 hours, the reaction rate of monomer (a) was confirmed after cooling to 70 ° C. Since the reaction rate of monomer (a) was less than 95%, the temperature was raised again to 170 ° C., and 1.1 parts of di-t-butyl peroxide was further added, and the reaction was allowed to proceed until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170° C. under reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain a crystalline vinyl resin (A2).
The weight average molecular weight of the crystalline vinyl resin (A2) measured by the above-mentioned method was 20,000, the endothermic peak top temperature was 58° C., and the xylene insoluble content was 1% by weight.

<Production Example 3> [Production of Crystalline Vinyl Resin (A3)]
110 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 170 ° C. in a sealed state under stirring. A mixed solution of 290 parts of C22 acrylate, 36 parts of N-vinylpyrrolidone, 145 parts of styrene, 181 parts of methyl acrylate, 73 parts of methacrylonitrile, 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 170 ° C. to polymerize. After dropping, the dropping line was washed with 8 parts of xylene. After further holding at the same temperature for 0.5 hours, it was cooled to 70 ° C. and the reaction rate of monomer (a) was confirmed. Since the reaction rate of monomer (a) was less than 95%, the temperature was raised again to 170 ° C., and 1.1 parts of di-t-butyl peroxide was further added, and the reaction was continued until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170° C. under reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain a crystalline vinyl resin (A3).
The weight average molecular weight of the crystalline vinyl resin (A3) measured by the above method was 39,000, the endothermic peak top temperature was 55° C., and the xylene insoluble content was 1% by weight.

<Production Example 4> [Production of Crystalline Vinyl Resin (A4)]
110 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 170 ° C. in a sealed state under stirring. A mixed solution of 363 parts of C22 acrylate, 7 parts of N-vinylpyrrolidone, 109 parts of styrene, 73 parts of methyl acrylate, 174 parts of methacrylonitrile, 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 170 ° C. to polymerize. After dropping, the dropping line was washed with 8 parts of xylene. After further holding at the same temperature for 0.5 hours, it was cooled to 70 ° C. and the reaction rate of monomer (a) was confirmed. Since the reaction rate of monomer (a) was less than 95%, the temperature was raised again to 170 ° C., and 1.1 parts of di-t-butyl peroxide was further added, and the reaction was allowed to proceed until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170° C. under reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain a crystalline vinyl resin (A4).
The weight average molecular weight of the crystalline vinyl resin (A4) measured by the above method was 35,000, the endothermic peak top temperature was 56° C., and the xylene insoluble content was 1% by weight.

<Production Example 5> [Production of Crystalline Vinyl Resin (A5)]
An autoclave was charged with 435 parts of stearyl acrylate [manufactured by Kyoeisha Chemical Co., Ltd., the same applies below] and 110 parts of xylene, and after replacing with nitrogen, the temperature was raised to 170 ° C. in a sealed state with stirring, and the temperature was controlled at 170 ° C. for 2 hours. A mixed solution of 261 parts of N-vinylpyrrolidone, 29 parts of styrene, 2.2 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 1.5 hours while controlling the temperature inside the autoclave to 170 ° C., and polymerization was performed. After dropping, the dropping line was washed with 8 parts of xylene. After further holding at the same temperature for 0.5 hours, it was cooled to 70 ° C., and the reaction rate of monomer (a) was confirmed. Since the reaction rate of monomer (a) was 95% or more, the temperature was raised again to 170 ° C., and the solvent was removed under a reduced pressure of 0.5 to 2.5 kPa for 5 hours, to obtain a crystalline vinyl resin (A5).
The weight average molecular weight of the crystalline vinyl resin (A5) measured by the above method was 28,000, the endothermic peak top temperature was 52° C., and the xylene insoluble content was 3% by weight.

<Production Example 6> [Production of Crystalline Vinyl Resin (A6)]
110 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 160°C in a sealed state under stirring. A mixed solution of 508 parts of C22 acrylate, 218 parts of N-vinylpyrrolidone, 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 160°C, and polymerization was carried out. After dropping, the dropping line was washed with 8 parts of xylene. After further holding at the same temperature for 1.3 hours, the reaction rate of the monomer (a) was confirmed after cooling to 70°C. Since the reaction rate of the monomer (a) was less than 95%, the temperature was raised again to 170°C, and 1.1 parts of di-t-butyl peroxide were further added, and the reaction was carried out until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170°C under a reduced pressure of 0.5 to 2.5 kPa for 5 hours, and a crystalline vinyl resin (A6) was obtained.
The weight average molecular weight of the crystalline vinyl resin (A6) measured by the above method was 33,000, the endothermic peak top temperature was 60° C., and the xylene insoluble content was 2% by weight.

<Production Example 7> [Synthesis of triacontyl acrylate]
In a reaction vessel equipped with a stirring device, a heating/cooling device, a thermometer, an air inlet tube, a pressure reducing device, and a water reducing device, 50 parts of 1-triacontanol [manufactured by Tokyo Chemical Industry Co., Ltd.], 50 parts of toluene, 12 parts of acrylic acid [manufactured by Mitsubishi Chemical Co., Ltd., the same below], and 0.05 parts of hydroquinone were added and stirred to make a homogenous mixture. Then, 2 parts of paratoluenesulfonic acid were added, and after stirring for 30 minutes, the mixture was reacted for 5 hours while removing the water generated at 100 ° C. while blowing in air at a flow rate of 30 mL / min. Thereafter, the pressure in the reaction vessel was adjusted to 300 mmHg, and the reaction was continued for another 3 hours while removing the water generated. After cooling the reaction solution to room temperature, 30 parts of a 10 wt% aqueous sodium hydroxide solution was added, and the mixture was stirred for 1 hour, and then allowed to stand to separate the organic phase and the aqueous phase. The organic phase was collected by liquid separation and centrifugation, 0.01 parts of hydroquinone was added, and the solvent was removed under reduced pressure while blowing in air to obtain triacontyl acrylate.

<Production Example 8> [Production of Crystalline Vinyl Resin (A7)]
110 parts of xylene was charged into an autoclave, and after replacing with nitrogen, the temperature was raised to 160°C in a sealed state under stirring. A mixed solution of 653 parts of triacontyl acrylate, 73 parts of N-vinylpyrrolidone, 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 170°C, and polymerization was carried out. After dropping, the dropping line was washed with 8 parts of xylene. After further maintaining at the same temperature for 0.5 hours, the reaction rate of monomer (a) was confirmed after cooling to 70°C. Since the reaction rate of monomer (a) was less than 95%, the temperature was raised again to 170°C, and 1.1 parts of di-t-butyl peroxide were further added, and the reaction was carried out until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170°C under a reduced pressure of 0.5 to 2.5 kPa for 5 hours, and a crystalline vinyl resin (A7) was obtained.
The weight average molecular weight of the crystalline vinyl resin (A7) measured by the above method was 30,000, the endothermic peak top temperature was 89° C., and the xylene insoluble content was 1% by weight.

Comparative Production Example 1 Production of Crystalline Vinyl Resin (A'1)
110 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 167 ° C. in a sealed state under stirring. A mixed solution of 435 parts of C22 acrylate, 36 parts of styrene, 73 parts of methyl acrylate, 181 parts of methacrylonitrile, 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 167 ° C. to polymerize. After dropping, the dropping line was washed with 8 parts of xylene. After further holding at the same temperature for 0.7 hours, it was cooled to 70 ° C. and the reaction rate of monomer (a) was confirmed. Since the reaction rate of monomer (a) was less than 95%, the temperature was raised again to 170 ° C., and 1.1 parts of di-t-butyl peroxide was further added, and the reaction was continued until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170° C. under a reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain a crystalline vinyl resin (A′1).
The weight average molecular weight of the crystalline vinyl resin (A'1) measured by the above-mentioned method was 30,000, the endothermic peak top temperature was 58°C, and the xylene insoluble content was 1% by weight.

Comparative Production Example 2 Production of Crystalline Vinyl Resin (A'2)
110 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 170 ° C. in a sealed state under stirring. A mixed solution of 283 parts of C22 acrylate, 36 parts of N-vinylpyrrolidone, 152 parts of styrene, 181 parts of methyl acrylate, 73 parts of methacrylonitrile, 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 170 ° C. to polymerize. After dropping, the dropping line was washed with 8 parts of xylene. After further holding at the same temperature for 0.5 hours, it was cooled to 70 ° C. and the reaction rate of monomer (a) was confirmed. Since the reaction rate of monomer (a) was less than 95%, the temperature was raised again to 170 ° C., and 1.1 parts of di-t-butyl peroxide was further added, and the reaction was continued until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170° C. under reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain a crystalline vinyl resin (A′2).
The weight average molecular weight of the crystalline vinyl resin (A'2) measured by the above method was 40,500, the endothermic peak top temperature was 55°C, and the xylene insoluble content was 1% by weight.

Comparative Production Example 3 Production of Crystalline Vinyl Resin (A'3)
110 parts of xylene was charged into an autoclave, and after replacing with nitrogen, the temperature was raised to 160°C in a sealed state under stirring. A mixed solution of 660 parts of triacontyl acrylate, 65 parts of N-vinylpyrrolidone, 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 170°C, and polymerization was carried out. After dropping, the dropping line was washed with 8 parts of xylene. After further maintaining at the same temperature for 0.5 hours, the reaction rate of the monomer (a) was confirmed after cooling to 70°C. Since the reaction rate of the monomer (a) was less than 95%, the temperature was raised again to 170°C, and 1.1 parts of di-t-butyl peroxide was further added, and the reaction was carried out until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170°C under a reduced pressure of 0.5 to 2.5 kPa for 5 hours, and a crystalline vinyl resin (A'3) was obtained.
The weight average molecular weight of the crystalline vinyl resin (A'3) measured by the above-mentioned method was 29,000, the endothermic peak top temperature was 89°C, and the xylene insoluble content was 1% by weight.

Comparative Production Example 4 Production of Crystalline Vinyl Resin (A'4)
110 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 160 ° C. in a sealed state under stirring. A mixed solution of 508 parts of C22 acrylate, 218 parts of dimethylacrylamide [manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., the same applies below], 0.7 parts of di-t-butyl peroxide, and 157 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 160 ° C. to polymerize. After dropping, the dropping line was washed with 8 parts of xylene. After further holding at the same temperature for 1.3 hours, the reaction rate of monomer (a) was confirmed after cooling to 70 ° C. Since the reaction rate of monomer (a) was less than 95%, the temperature was raised again to 170 ° C., and 1.1 parts of di-t-butyl peroxide was further added and reacted until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170° C. under reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain a crystalline vinyl resin (A′4).
The weight average molecular weight of the crystalline vinyl resin (A'4) measured by the above-mentioned method was 34,000, the endothermic peak top temperature was 60°C, and the xylene insoluble content was 2% by weight.

The compositions and physical properties of crystalline vinyl resins (A1) to (A7) and (A'1) to (A'4) are shown in Table 1.

<Production Example 9> [Production of amorphous vinyl resin (B1)]
100 parts of xylene was charged into the autoclave, and after replacing with nitrogen, the temperature was raised to 150°C in a sealed state under stirring. A mixed solution of 443 parts of styrene, 167 parts of butyl acrylate [manufactured by Idemitsu Kosan Co., Ltd., the same applies below], 9.3 parts of acrylic acid, 0.5 parts of di-t-butyl peroxide, and 143 parts of xylene was dropped over 3 hours while controlling the temperature inside the autoclave to 150°C, and polymerization was carried out. After dropping, the dropping line was washed with 11 parts of xylene. After further holding at the same temperature for 1 hour, the temperature was raised to 170°C over 1 hour, and the same temperature was held for 0.5 hours. Thereafter, it was cooled to 100°C, and the reaction rate of butyl acrylate was confirmed. Since the reaction rate of butyl acrylate was less than 95%, the temperature was raised again to 170°C, and 1.5 parts of di-t-butyl peroxide were further added, and the reaction was carried out until the reaction rate was 95% or more. Thereafter, the solvent was removed at 170° C. under a reduced pressure of 0.5 to 2.5 kPa for 5 hours to obtain an amorphous vinyl resin (B1).
The amorphous vinyl resin (B1) had a weight average molecular weight of 56,500, a glass transition temperature of 58° C., and an acid value of 11 mgKOH/g, as measured by the above-mentioned methods.

Example 1: Production of toner binder (D1) and toner (Ts1)
30 parts of crystalline vinyl resin (A1) and 70 parts of amorphous vinyl resin (B1) were premixed to obtain a toner binder (D1). Next, the obtained toner binder (D1), 6 parts of a pigment carbon black [manufactured by Mitsubishi Chemical Corporation, MA-100], 4 parts of a release agent carnauba wax [manufactured by Nippon Wax Co., Ltd., carnauba wax], and 4 parts of a charge control agent Eisenspiron Black [manufactured by Hodogaya Chemical Co., Ltd., T-77] were made into a toner by the following method. First, each raw material was premixed using a Henschel mixer [manufactured by Nippon Coke & Engineering Co., Ltd., FM10B], and then kneaded with a twin-screw kneader [manufactured by Ikegai Corporation, PCM-30]. The resulting mixture was then finely pulverized using a supersonic jet mill, Labojet [LJ type, manufactured by Nippon Pneumatic Mfg. Co., Ltd.], and classified using an air classifier [MDS-1, manufactured by Nippon Pneumatic Mfg. Co., Ltd.] to obtain colored resin particles. Finally, 100 parts of the colored resin particles were mixed with 1 part of hydrophobic silica [Aerosil R972, manufactured by Nippon Aerosil Mfg. Co., Ltd.] as a fluidizing agent using a sample mill to obtain a toner (Ts1).

<Examples 2 to 9> [Production of toner binders (D2) to (D9) and toners (Ts2) to (Ts7)]
Toner binders (D2) to (D9) and toners (Ts1) to (Ts9) were obtained in the same manner as in Example 1, except that the compositions shown in Table 2 were used.

<Production Example 10> [Production of polyester resin (C0)]
In a pressurized reaction vessel equipped with a stirrer, a heating/cooling device, a thermometer, an air inlet tube, a pressure reducing device, and a water reducing device, 251 parts of neopentyl glycol, 334 parts of 1,2-propanediol, 633 parts of terephthalic acid, and 31 parts of behenic acid were added and stirred to homogenize. Then, 2 parts of titanium diisopropoxy bistriethanol aminate were added and homogenized for 30 minutes, and pressure esterification was performed at 227°C and 0.45 MPa for 5 hours, and it was confirmed that the acid value was 10 mgKOH/g. Then, pressure esterification was performed at 4 kPa or less, 161 parts of 1,2-propanediol was recovered, and it was confirmed that the acid value was 1 mgKOH/g and Mw was 2500, and the mixture was cooled to 180°C, and 2 parts of 2,6-di-tert-butyl-4-methylphenol were added and homogenized for 30 minutes. Then, 68 parts of fumaric acid was added, and esterification at normal pressure at 180° C. for 2 hours was performed, followed by esterification at reduced pressure at 4 kPa or less for 15 hours, and the mixture was taken out of the reaction vessel to obtain polyester resin (C0). The weight average molecular weight of polyester resin (C0) measured by the above method was 7600, the glass transition temperature was 50° C., and the acid value was 3 mgKOH/g.

Example 10: [Preparation of toner binder (D10) and toner (Ts10)]
In a reaction vessel equipped with a stirrer, a heating/cooling device, a thermometer, a nitrogen inlet tube, a pressure reducing device, and a water reducing device, 60 parts of polyester resin (C0) and 40 parts of crystalline vinyl resin (A1) were charged, and the temperature was raised to 115°C while nitrogen was flowing. After holding at 115°C for 1 hour, the nitrogen flow was stopped, and 0.6 parts of t-butylperoxy-2-ethylhexanoate as a radical reaction initiator (c-1) was dropped under normal pressure over 15 minutes while controlling the temperature in the reaction vessel to 115°C, and the same temperature was held for another 40 minutes. Thereafter, the solvent was removed at 110°C for 1 hour under a reduced pressure of 0.5 to 2.5 kPa, and a toner binder (D10) containing a nonlinear polyester resin (C1) in which polyester resin (C0) was crosslinked by a carbon-carbon bond and a crystalline vinyl resin (A1) was obtained.
In addition, when only the polyester resin (C0) was subjected to a crosslinking reaction using t-butylperoxy-2-ethylhexanoate to obtain a nonlinear polyester resin (C1), the glass transition temperature of the nonlinear polyester resin (C1) measured by the above method was 50°C and the acid value was 3 mgKOH/g.
Next, the obtained toner binder (D10), 6 parts of a pigment carbon black [manufactured by Mitsubishi Chemical Corporation, MA-100], 4 parts of a release agent carnauba wax [manufactured by Nippon Wax Co., Ltd., Carnauba wax], and 4 parts of a charge control agent Aizenspiron Black [manufactured by Hodogaya Chemical Co., Ltd., T-77] were made into a toner by the following method. First, each raw material was premixed using a Henschel mixer [manufactured by Nippon Coke & Engineering Co., Ltd., FM10B], and then kneaded with a twin-screw kneader [manufactured by Ikegai Corporation, PCM-30]. Next, the mixture was finely pulverized using a supersonic jet pulverizer Lab Jet [manufactured by Nippon Pneumatic Mfg. Co., Ltd., LJ type], and then classified with an air classifier [manufactured by Nippon Pneumatic Mfg. Co., Ltd., MDS-1] to obtain colored resin particles. Finally, 100 parts of the colored resin particles were mixed with 1 part of hydrophobic silica (Aerosil R972, manufactured by Nippon Aerosil Co., Ltd.) as a fluidizing agent in a sample mill to obtain a toner (Ts10).

Comparative Examples 1 to 4 [Production of Toner Binders (D'1) to (D'4) and Toners (Ts'1) to (Ts'4)]
Toner binders (D'1) to (D'4) and toners (Ts'1) to (Ts'4) were obtained in the same manner as in Example 1, except that the compositions shown in Table 2 were used.

The toners (Ts1) to (Ts10) obtained in Examples 1 to 10 and the comparative toners (Ts'1) to (Ts'4) obtained in Comparative Examples 1 to 4 were evaluated for low-temperature fixability (MFT), hot offset resistance (hot offset temperature), storage stability under high temperature and high humidity conditions, and hydrolysis resistance using the following methods. The results are shown in Table 2.

<Low temperature fixability>
The toner was uniformly placed on the paper surface to a concentration of 1.00 mg/ ^cm2 . The powder was placed on the paper surface using a printer without a thermal fixing device. The paper was passed through a soft roller at a fixing speed (heating roller peripheral speed) of 213 mm/sec and at a heating roller temperature range of 90 to 230°C in 5°C increments. The fixed image was then visually inspected for the presence or absence of cold offset, and the cold offset occurrence temperature (MFT) was measured.
The lower the temperature at which cold offset occurs, the better the low-temperature fixing ability. Under these evaluation conditions, it is generally preferable that the MFT is 125° C. or less.

<Hot offset resistance (hot offset temperature)>
In the same manner as described above for low-temperature fixability, the toner was placed on the paper surface, and the paper was passed through a soft roller at a fixing speed (heating roller peripheral speed) of 213 mm/sec, and at a heating roller temperature range of 90 to 230° C. in increments of 5° C. Next, the presence or absence of hot offset on the fixed image was visually observed, and the temperature at which hot offset occurred was measured.
A higher hot offset occurrence temperature means better hot offset resistance. In this evaluation condition, a temperature of 150° C. or higher is preferable.

<Storage stability under high temperature and humidity conditions>
1 g of toner and 0.01 g of hydrophobic silica (Aerosil R8200, manufactured by Evonik Japan Co., Ltd.) were mixed for 1 hour using a shaker. The mixture was placed in an open glass container and left to stand for 48 hours in an atmosphere at a temperature of 40° C. and a humidity of 80%. The degree of blocking was visually judged, and the storage stability was evaluated according to the following criteria.
◎: No blocking has occurred and there is no visible change in fluidity. 〇: Blocking has occurred in some areas, but the agglomerates break down and the material flows when the container is shaken. △: Blocking has occurred throughout the material, but the agglomerates break down and the material flows when the container is shaken. ×: Blocking has occurred, and the agglomerates do not break down (do not flow) even when the container is shaken.
In this evaluation condition, a rating of 0 or higher is preferable.

<Hydrolysis resistance>
1 g of the toner was placed in an open glass container and left to stand for 10 days in an atmosphere at a temperature of 95° C. and a humidity of 95%. The weight average molecular weight and the storage modulus (Pa) at 100° C. were measured by GPC before and after the test to confirm the changes in the weight average molecular weight and the storage modulus, and the hydrolysis resistance was evaluated according to the following criteria.
◎: Changes in both weight-average molecular weight and storage modulus are less than ±3% ◯: Changes in both weight-average molecular weight and storage modulus are between ±3% and less than 5% △: Changes in weight-average molecular weight are between ±5% and ±5%, but changes in storage modulus are less than ±5% ×: Changes in both weight-average molecular weight and storage modulus are between ±5% and ±5% Note that the storage modulus (Pa) at 100°C is the storage modulus (Pa) at 100°C measured using a viscoelasticity measuring device (ARES-24A, manufactured by Rheometrics) by mounting a pressure-molded sample on a disk having a diameter of 8 mm and a thickness of 2.0±0.3 mm on a parallel plate, heating the sample from room temperature (25°C) to 100°C, adjusting the shape of the sample, cooling it to 40°C, and measuring from 40 to 180°C. The measurement was performed under the following conditions.
Jig: 8 mm parallel plate Frequency: 1 Hz
Distortion rate: 1%
Heating rate: 5° C./min
In this evaluation condition, a rating of 0 or higher is preferable.

As is clear from the evaluation results in Table 2, the toners (Ts1) to (Ts10) containing the toner binder of the present invention have good low-temperature fixing property, hot offset resistance, storage stability under high temperature and high humidity conditions, and hydrolysis resistance.
On the other hand, the toners (Ts'1) to (Ts'4) containing the comparative toner binders were inferior in at least one of the evaluation results of low temperature fixing property, hot offset resistance, storage stability under high temperature and high humidity conditions, and hydrolysis resistance.

Claims (5)

A toner binder containing a crystalline vinyl resin (A),
A toner binder, wherein the crystalline vinyl resin (A) is a polymer of a monomer composition (A0) containing a monomer (a) and a monomer (b), the monomer (a) is a (meth)acrylate having a chain-like hydrocarbon group and having 21 to 40 carbon atoms, the monomer (b) is a monomer having an amide bond and a cyclic structure, and the weight ratio of the monomer (a) is 40 to 90% by weight based on the weight of the monomer composition (A0). 2. The toner binder according to claim 1, wherein the monomer (b) is a compound represented by the following formula (1) and/or formula (2):

[In general formula (1), R ¹ is a hydrogen atom or a methyl group, R ² is an alkylene group having 2 to 5 carbon atoms, and in general formula (2), R ³ is a hydrogen atom or a methyl group, R ⁴ is each independently an alkylene group having 1 to 5 carbon atoms, and X represents an oxygen atom, a nitrogen atom, or a direct bond.] The toner binder according to claim 1 or 2, wherein the weight ratio of the monomer (b) is 1 to 35% by weight based on the weight of the monomer composition (A0). The toner binder according to claim 1 or 2, wherein the xylene-insoluble content of the crystalline vinyl resin (A) is 6% by weight or less. 3. The toner binder according to claim 1, wherein the weight ratio of said crystalline vinyl resin (A) is 10 to 60% by weight based on the weight of the toner binder.