Binder resin composition for toner

Abstract

To provide a toner binder resin composition used for electro-photographic toner and capable of improving the image quality of a printed matter, such as fine line reproducibility.SOLUTION: A toner binder resin composition includes a condensate (AT) of: a polyester resin segment being the condensation polymer of an alcohol component and a carboxylic acid component including an aromatic dicarboxylic acid of 80 mol% or more; a vinyl resin segment being the addition polymer of a raw material monomer including a styrene based compound; and a tertiary amine (T).SELECTED DRAWING: None

Description

Technical Field

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

Background Art

[0002] In the field of electrophotography, with the development of electrophotographic systems, the development of toners corresponding to high image quality and high speed has been demanded. In Patent Document 1, a resin composition obtained by condensing a colorant, an amorphous polyester resin having an acid group and an amine compound, an ester composition (CI) containing a carboxylic acid component containing 20 mol% or more of an aliphatic monocarboxylic acid compound, and a condensate of an alcohol component containing 90 mol% or more of a divalent or higher aliphatic alcohol, and an ester composition selected from one or more ester compositions (CII) containing a condensate of an alcohol component containing 20 mol% or more of an aliphatic monohydric alcohol and a carboxylic acid component containing 90 mol% or more of a divalent or higher aliphatic carboxylic acid compound are included. An electrostatic charge image developing toner is described. The toner is described as being excellent in image density and gloss. In Patent Document 2, a dry toner using a polyester in which at least a part of COOH is replaced by a functional group containing N such as amine, ammonium, betaine, pyridinium salt, or azine is described. The toner is described as showing stable developability against environmental changes and over time as a positive-charged toner for positive development of a negative electrostatic latent image.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, further improvement in image quality corresponding to higher image quality and higher speed is required. The present invention relates to a toner binder resin composition capable of improving the image quality of printed matter such as fine line reproducibility when used in an electrophotographic toner.

Means for Solving the Problems

[0005] The present inventors have found that the above problems can be solved by a toner binder resin composition containing a condensate of a polyester resin segment, a vinyl resin segment, and a tertiary amine.

[0006] That is, the present invention relates to the following [1] to [3]. [1] A toner binder resin composition containing a condensate (AT) of a polyester resin segment which is a polycondensate of a carboxylic acid component containing 80 mol% or more of an alcohol component and an aromatic dicarboxylic acid, a vinyl resin segment which is an addition polymer of a raw material monomer containing a styrene-based compound, and a tertiary amine (T). [2] An electrophotographic toner containing the toner binder resin composition according to [1]. [3] A method for producing the toner binder resin composition according to [1], including the following steps 1 and 2. Step 1: A step of condensing a polyester resin segment, a vinyl resin segment, and a tertiary amine (T) to obtain a reaction mixture containing a condensate (AT). Step 2: A step of steaming the reaction mixture obtained in Step 1.

Advantages of the Invention

[0007] According to the present invention, it is possible to provide a toner binder resin composition capable of improving the image quality of printed matter such as fine line reproducibility when used in an electrophotographic toner.

Modes for Carrying Out the Invention

[0008] [Binder resin composition for toner] The binder resin composition for toner of the present invention contains a condensate (AT) of a polyester resin segment which is a polycondensate of a carboxylic acid component containing 80 mol% or more of an alcohol component and an aromatic dicarboxylic acid, a vinyl resin segment which is an addition polymer of a raw material monomer containing a styrene-based compound, and a tertiary amine (T). By having the above configuration, a binder resin composition for toner that can improve the image quality of printed matter such as fine line reproducibility can be obtained when used in electrophotographic toner. The reason is not clear, but it is considered as follows.

[0009] The toner binder resin composition of the present invention contains a condensate (AT) of a polyester resin segment, a vinyl resin segment which is an addition polymer of a raw material monomer containing a styrene-based compound, and a tertiary amine (T). The condensate (AT) has a polyester resin segment with relatively easy molecular motion and a vinyl resin segment which is an addition polymer of a raw material monomer containing a styrene-based compound with a high aromatic ring concentration and relatively difficult molecular motion. Thus, the polyester resin segment is easily polarized, and the vinyl resin segment is less likely to be polarized. Further, since the condensate (AT) contains a tertiary amine (T), a positive charge property can be imparted to the nitrogen atom of the obtained condensate (AT). Therefore, in the condensate (AT) contained in the toner binder resin composition of the present invention, segments that are easily polarized and segments that are less likely to be polarized coexist in the same molecule, making it difficult for positive and negative pairs with respect to the electric field in the condensate (AT) to occur, and the polarization becoming larger, so that the improvement of the dielectric constant and the increase of the positive charge property due to the inclusion of the tertiary amine (T) are strongly exhibited. Also, since 80 mol% or more of the carboxylic acid component constituting the polyester resin segment contained in the condensate (AT) is an aromatic dicarboxylic acid and the aromatic ring concentration of the polyester resin segment is high, the toner containing the toner binder resin composition of the present invention can maintain charge for a long time. Furthermore, since the condensate (AT) contained in the toner binder resin composition of the present invention has a high aromatic ring concentration and a high charge transfer rate, the charging rise when the toner is charged by friction with a charging blade becomes faster, and the charging stability of the toner can be improved. As a result, it is considered that the toner containing the toner binder resin composition of the present invention has an improved dielectric constant and is easily maintained in a positively charged state, thereby improving the image quality of printed matter such as fine line reproducibility.

[0010] The definitions of various terms in this specification are shown below. Whether the resin is crystalline or amorphous is determined by the crystallinity index. The crystallinity index is defined as the ratio of the softening point of the resin to the maximum peak temperature of endotherm (softening point (°C) / maximum peak temperature of endotherm (°C)) in the measurement method described in the examples below. A crystalline resin is a resin with a crystallinity index of 0.6 or more and 1.4 or less. An amorphous resin is a resin in which no endothermic peak is observed, or if an endothermic peak is observed, the crystallinity index is more than 1.4 or less than 0.6. The crystallinity index can be appropriately adjusted according to the type and ratio of the raw material monomers, and manufacturing conditions such as reaction temperature, reaction time, and cooling rate. Note that the maximum peak temperature of endotherm refers to the temperature of the peak with the largest peak area among the endothermic peaks observed under the conditions of the measurement method described in the examples. In the specification, the carboxylic acid component of the polyester resin includes not only the exemplified compounds, but also anhydrides that decompose during the reaction to generate acids, and alkyl esters of each carboxylic acid (alkyl group having 1 to 3 carbon atoms). In the specification, the "binder resin composition" means the resin component contained in the toner containing the condensate (AT).

[0011] <Condensate (AT)> The condensate (AT) is a condensate of a polyester resin segment, a vinyl resin segment, and a tertiary amine (T). The condensate (AT) is preferably amorphous. The condensate (AT) is preferably a condensate (AT') formed by the condensation reaction of a composite resin (A) containing a polyester resin segment and a vinyl resin segment and a tertiary amine (T). The condensate (AT) may contain, for example, unreacted composite resin (A) to such an extent that its properties are not substantially impaired, but from the viewpoint of obtaining a printed matter with excellent image quality with improved thin line reproducibility by suppressing charge leakage due to the tertiary amine (T) when used as an electrophotographic toner and suppressing a decrease in the chargeability of the toner, it is preferably free of the tertiary amine (T). The condensate (AT) is preferably an amorphous resin.

[0012] 〔Polyester resin segment〕 Examples of the alcohol component of the polyester resin segment include, for example, an alkylene oxide adduct of an aromatic diol, a linear or branched aliphatic diol, an alicyclic diol, and a polyhydric alcohol having a valence of 3 or more. Among these, from the viewpoint of improving the molecular mobility of the polyester resin segment in the condensate (AT) and improving the fine line reproducibility, an alkylene oxide adduct of an aromatic diol is preferable.

[0013] The alkylene oxide adduct of an aromatic diol is preferably an alkylene oxide adduct of bisphenol A, and more preferably has the formula (I):

[0014]

Chemical formula

[0015] Examples of the alkylene oxide adduct of bisphenol A include, for example, a propylene oxide adduct of bisphenol A [2,2-bis(4-hydroxyphenyl)propane] and an ethylene oxide adduct of bisphenol A. These may be used alone or in combination of two or more. From the viewpoint of improving the molecular mobility of the polyester resin segment in the condensate (AT) and improving the fine line reproducibility, the content of the alkylene oxide adduct of bisphenol A is preferably 70 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol% or less, and still more preferably 100 mol% in the alcohol component.

[0016] Examples of the linear or branched aliphatic diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 2,2-dimethyl-1,3-propanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-dodecanediol. Examples of the alicyclic diol include hydrogenated bisphenol A [2,2-bis(4-hydroxycyclohexyl)propane] and an alkylene oxide adduct (average number of moles added: 2 or more and 12 or less) of hydrogenated bisphenol A having 2 or more and 4 or less carbon atoms. Examples of the polyhydric alcohol having a valency of 3 or more include glycerin, pentaerythritol, trimethylolpropane, and sorbitol. These alcohol components may be used alone or in combination of two or more.

[0017] From the viewpoint of improving the molecular mobility of the polyester resin segment in the condensate (AT) and improving the fine line reproducibility, the carboxylic acid component of the polyester resin segment contains 80 mol% or more of an aromatic dicarboxylic acid. The carboxylic acid component may contain a dicarboxylic acid other than the aromatic dicarboxylic acid and a polyvalent carboxylic acid having a valency of 3 or more. Hereinafter, the dicarboxylic acid and / or the polyvalent carboxylic acid having a valency of 3 or more is also simply referred to as "polyvalent carboxylic acid". Examples of the aromatic dicarboxylic acid include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid and terephthalic acid are preferable, and terephthalic acid is more preferable. From the viewpoint of improving the molecular mobility of the polyester resin segment in the condensate (AT) and improving the fine line reproducibility, the amount of the aromatic dicarboxylic acid is 80 mol% or more, preferably 82 mol% or more, more preferably 85 mol% or more, and preferably 95 mol% or less, more preferably 93 mol% or less, still more preferably 90 mol% or less in the carboxylic acid component.

[0018] Examples of dicarboxylic acids other than aromatic dicarboxylic acids include linear or branched aliphatic dicarboxylic acids and alicyclic dicarboxylic acids. The number of carbon atoms of the linear or branched aliphatic dicarboxylic acid is preferably 2 or more, more preferably 3 or more, and preferably 30 or less, more preferably 20 or less. Examples of the linear or branched aliphatic dicarboxylic acid include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, azelaic acid, and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms. Examples of the succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include dodecylsuccinic acid, dodecenylsuccinic acid, and octenylsuccinic acid. Examples of the alicyclic dicarboxylic acid include cyclohexanedicarboxylic acid. Among these, linear or branched aliphatic dicarboxylic acids are preferred, fumaric acid, sebacic acid, and succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms are more preferred, and fumaric acid is even more preferred. The amount of the linear or branched aliphatic dicarboxylic acid is preferably 5 mol% or more, more preferably 7 mol% or more, still more preferably 10 mol% or more in the carboxylic acid component, and preferably 20 mol% or less, more preferably 18 mol% or less, still more preferably 15 mol% or less.

[0019] The polyvalent carboxylic acid having a valence of 3 or more is preferably a trivalent carboxylic acid, and examples thereof include trimellitic acid. Preferably, it is trimellitic acid or its anhydride. When a polyvalent carboxylic acid having a valence of 3 or more is included, the amount of the polyvalent carboxylic acid having a valence of 3 or more is preferably 3 mol% or more, more preferably 5 mol% or more, still more preferably 8 mol% or more in the carboxylic acid component, and preferably 20 mol% or less, more preferably 17 mol% or less, still more preferably 15 mol% or less. These carboxylic acid components may be used alone or in combination of two or more.

[0020] The equivalent ratio of the carboxy group of the carboxylic acid component to the hydroxyl group of the alcohol component [COOH group / OH group] is preferably 0.7 or more, more preferably 0.8 or more, and preferably 1.3 or less, more preferably 1.2 or less.

[0021] [Vinyl resin segment] The vinyl resin segment is an addition polymer of a raw material monomer containing a styrene compound. Examples of the styrene compound include unsubstituted or substituted styrene. Examples of the substituent for styrene include an alkyl group having 1 to 5 carbon atoms, a halogen atom, an alkoxy group having 1 to 5 carbon atoms, a sulfonic acid group, or a salt thereof. Examples of the styrene compound include styrene, methylstyrene, α-methylstyrene, β-methylstyrene, tert-butylstyrene, chlorostyrene, chloromethylstyrene, methoxystyrene, styrenesulfonic acid, or a salt thereof. Among these, styrene is preferable. In the raw material monomer of the vinyl resin segment, the content of the styrene compound is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and 100% by mass or less, and still more preferably 100% by mass, from the viewpoint of suppressing the polarization of the vinyl resin segment in the condensate (AT) and improving the reproducibility of fine lines.

[0022] When the raw material monomers constituting the vinyl resin segment include raw material monomers other than styrene compounds, examples of the raw material monomers include (meth)acrylic acid esters such as alkyl (meth)acrylates, benzyl (meth)acrylate, and dimethylaminoethyl (meth)acrylate; olefins such as ethylene, propylene, and butadiene; halovinyls such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether; vinylidene chlorides such as vinylidene chloride; and N-vinyl compounds such as N-vinylpyrrolidone. Among these, (meth)acrylic acid esters are preferred, and alkyl (meth)acrylates are more preferred. The number of carbon atoms in the alkyl group of the alkyl (meth)acrylate is preferably 1 or more, more preferably 4 or more, still more preferably 6 or more, and preferably 24 or less, more preferably 22 or less, still more preferably 20 or less. Examples of the alkyl (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, (iso)propyl (meth)acrylate, (iso or tertiary)butyl (meth)acrylate, (iso)amyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (iso)octyl (meth)acrylate, (iso)decyl (meth)acrylate, (iso)dodecyl (meth)acrylate, (iso)palmitoyl (meth)acrylate, (iso)stearyl (meth)acrylate, (iso)behenyl (meth)acrylate, etc., preferably 2-ethylhexyl (meth)acrylate or stearyl (meth)acrylate, more preferably 2-ethylhexyl acrylate or stearyl methacrylate, and still more preferably 2-ethylhexyl acrylate. Note that “(iso or tertiary)” and “(iso)” mean both the cases where these prefixes are present and the cases where they are not present, and when these prefixes are not present, it indicates normal. Also, “(meth)acrylic acid” indicates acrylic acid or methacrylic acid.

[0023] When the raw material monomers constituting the vinyl resin segment contain (meth)acrylic acid ester, the content of (meth)acrylic acid ester in the raw material monomers of the vinyl resin segment is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and preferably 30% by mass or less, more preferably 25% by mass or less, still more preferably 20% by mass or less. The total amount of the styrenic compound and (meth)acrylic acid ester in the raw material monomers of the vinyl resin segment is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and still more preferably 100% by mass.

[0024] [Structural unit derived from the bifunctional monomer] The condensate (AT) preferably has a structural unit derived from a bifunctional monomer bonded via a covalent bond to the polyester resin segment and the vinyl resin segment. The "structural unit derived from the bifunctional monomer" means a unit in which a functional group or an addition-polymerizable group of the bifunctional monomer has reacted. Examples of the addition-polymerizable group include a carbon-carbon unsaturated bond (ethylenic unsaturated bond). Examples of the bifunctional monomer include an addition-polymerizable monomer having at least one functional group selected from a hydroxyl group, a carboxy group, an epoxy group, a primary amino group, and a secondary amino group in the molecule. Among these, from the viewpoint of reactivity, an addition-polymerizable monomer having at least one functional group selected from a hydroxyl group and a carboxy group is preferable, and an addition-polymerizable monomer having a carboxy group is more preferable. Examples of the addition-polymerizable monomer having a carboxy group include acrylic acid, methacrylic acid, fumaric acid, and maleic acid. Among these, from the viewpoint of the reactivity of both the polycondensation reaction and the addition-polymerization reaction, acrylic acid and methacrylic acid are preferable, and acrylic acid is more preferable. When the both-reactive monomer is an addition polymerizable monomer having a carboxy group, the amount of the structural unit derived from the both-reactive monomer is preferably 0.5 mol part or more, more preferably 1 mol part or more, still more preferably 2 mol part or more, and preferably 15 mol parts or less, more preferably 10 mol parts or less, still more preferably 7 mol parts or less, per 100 mol parts of the alcohol component of the polyester resin segment of the condensate (AT).

[0025] The content of the vinyl resin segment in the condensate (AT) is preferably 5% by mass or more, more preferably 7% by mass or more, still more preferably 8% by mass or more, still more preferably 13% by mass or more, still more preferably 17% by mass or more, and preferably 30% by mass or less, more preferably 25% by mass or less, still more preferably 23% by mass or less, based on the total amount of the polyester resin segment and the vinyl resin segment. The content of the polyester resin segment in the condensate (AT) is preferably 70% by mass or more, more preferably 75% by mass or more, still more preferably 77% by mass or more, and preferably 95% by mass or less, more preferably 93% by mass or less, still more preferably 92% by mass or less, still more preferably 87% by mass or less, still more preferably 83% by mass or less, based on the total amount of the polyester resin segment and the vinyl resin segment. The structural unit derived from the both-reactive monomer is calculated including in the polyester resin segment.

[0026] The content of the structural unit derived from the both-reactive monomer in the condensate (AT) is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, still more preferably 0.3% by mass or more, and preferably 10% by mass or less, more preferably 7% by mass or less, still more preferably 4% by mass or less, based on the total amount of the polyester resin segment and the vinyl resin segment.

[0027] The above amounts are calculated based on the ratios of the amounts of the polyester resin segment, the raw material monomers of the vinyl resin segment, the bifunctional monomer, and the radical polymerization initiator. The mass of the polyester resin segment and the like is based on the mass excluding the mass of water generated by polycondensation. When a radical polymerization initiator is used, the mass of the radical polymerization initiator is calculated including it in the vinyl resin segment.

[0028] (Tertiary amine (T)) Examples of the tertiary amine (T) include a tertiary amine (T1) having a hydroxyalkyl group, a tertiary amine (T2) having a carboxyalkyl group, and a tertiary amine (T3) having an addition-polymerizable functional group. Examples of the tertiary amine (T1) having a hydroxyalkyl group include triethanolamine, triisopropanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N,N-dipropylethanolamine, N,N-diisopropylethanolamine, N,N-dibutylethanolamine, 3-dimethylamino-1-propanol, 3-diethylamino-1-propanol, 3-dipropylamino-1-propanol, 3-diisopropylamino-1-propanol, 3-dibutylamino-1-propanol, 4-dimethylamino-1-butanol, 4-diethylamino-1-butanol, 4-dipropylamino-1-butanol, 4-diisopropylamino-1-butanol, 4-dibutylamino-1-butanol, 3-dimethylamino-1,2-propanediol, 3-diethylamino-1,2-propanediol, 3-dipropylamino-1,2-propanediol, 3-diisopropylamino-1,2-propanediol, and the like. Examples of the tertiary amine (T2) having a carboxyalkyl group include N,N-dimethylglycine, N,N-diethylglycine, N,N-dipropylglycine, N,N-diisopropylglycine, N,N-dibutylglycine, N-methyliminodiacetic acid, N-ethyliminodiacetic acid, N-propyliminodiacetic acid, N-isopropyliminodiacetic acid, N-butyliminodiacetic acid, 1-pyrrolidineacetic acid, 1-piperidineacetic acid, nitrilotriacetic acid, N-(2-carboxyethyl)iminodiacetic acid, 3-dimethylaminopropionic acid, 3-diethylaminopropionic acid, 3-dipropylaminopropionic acid, 3-diisopropylaminopropionic acid, 3-dibutylaminopropionic acid, N-methyl-3,3'-iminodipropionic acid, N-ethyl-3,3'-iminodipropionic acid, N-propyl-3,3'-iminodipropionic acid, N-isopropyl-3,3'-iminodipropionic acid, N-butyl-3,3'-iminodipropionic acid, 3-(1-pyrrolidine)propionic acid, 3-(1-piperidine)propionic acid, 3,3',3''-nitrilotripropionic acid and the like. Examples of the tertiary amine (T3) having an addition polymerizable functional group include N,N-dimethylallylamine, N,N-diethylallylamine, N,N-dipropylallylamine, N,N-diisopropylallylamine, N,N-dibutylallylamine, 1-allylpyrrolidine, 1-allylpiperidine, triallylamine and the like. Moreover, a monoester obtained by a condensation reaction of a tertiary amine (T1) having a hydroxyalkyl group and a dicarboxylic acid, or a (meth)acrylic acid ester obtained by a condensation reaction of a tertiary amine (T1) having a hydroxyalkyl group and (meth)acrylic acid may be used as the tertiary amine (T). As the dicarboxylic acid, the dicarboxylic acids mentioned as the carboxylic acid component of the polyester resin segment can be used, and an aliphatic dicarboxylic acid is preferable. Among these, the tertiary amine (T) is preferably a tertiary amine (T1) having a hydroxyalkyl group for introduction into the condensate (AT).

[0029] The boiling point of the tertiary amine (T) at 1 atm is preferably 130 °C or higher, more preferably 140 °C or higher, still more preferably 150 °C or higher, and preferably 300 °C or lower, more preferably 270 °C or lower, still more preferably 250 °C or lower, from the viewpoint of the productivity of the condensate (AT). When two or more tertiary amines (T) are used, the boiling point of the tertiary amine is calculated as a weighted average value. The molecular weight of the tertiary amine (T) is preferably 230 or lower, more preferably 210 or lower, still more preferably 200 or lower, and preferably 100 or higher, from the viewpoint of enhancing the positive chargeability of the condensate (AT).

[0030] The tertiary amine (T) is preferably a tertiary amine (T1) having a hydroxyalkyl group, more preferably a tertiary amine having a hydroxyalkyl group with 2 or 3 carbon atoms and a linear or branched alkyl group with 1 to 4 carbon atoms, and still more preferably 3-dimethylamino-1-propanol, N-methyldiethanolamine, and N,N-dibutylethanolamine. These tertiary amines can be used alone or in combination of two or more.

[0031] The content of the structural unit derived from the tertiary amine (T) in the condensate (AT) is preferably 0.5% by mass or more, more preferably 1% by mass or more, still more preferably 1.5% by mass or more, and preferably 5% by mass or less, more preferably 4% by mass or less, still more preferably 3% by mass or less, from the viewpoints of improving the dielectric constant of the condensate (AT), increasing the positive chargeability, and improving the fine line reproducibility.

[0032] (Composite resin (A)) The composite resin (A) includes a polyester resin segment that is a polycondensate of an alcohol component and a carboxylic acid component, and a vinyl resin segment that is an addition polymer of a raw material monomer containing a styrene-based compound. Also, the composite resin (A) is preferably amorphous. The composite resin (A) preferably has a polyester resin segment and a vinyl resin segment bonded via a covalent bond to a bifunctional monomer. Examples of the alcohol component and carboxylic acid component of the polyester resin segment, the raw material monomers of the vinyl resin segment, and the bifunctional monomer include the same as those shown in the condensate (AT), and the preferred ranges are also the same.

[0033] 〔Method for producing condensate (AT)〕 The method for producing the condensate (AT) includes a step 1 of condensing a polyester resin segment, a vinyl resin segment, and a tertiary amine (T) to obtain a reaction mixture containing the condensate (AT). The condensate (AT) may be produced by a method including a polycondensation step of polycondensing an alcohol component and a carboxylic acid component in the presence of a tertiary amine (T), and an addition polymerization step of addition polymerizing the raw material monomers of the vinyl resin segment and the bifunctional monomer. Further, the condensate (AT) may be produced by a method including a polycondensation step of polycondensing an alcohol component and a carboxylic acid component, and an addition polymerization step of addition polymerizing the raw material monomers of the vinyl resin segment and the bifunctional monomer in the presence of a tertiary amine (T). The addition polymerization step may be carried out after the polycondensation step, the polycondensation step may be carried out after the addition polymerization step, or the polycondensation step and the addition polymerization step may be carried out simultaneously. The method for producing the condensate (AT) preferably condenses a composite resin (A) containing a polyester resin segment and a vinyl resin segment with a tertiary amine (T) to produce a condensate (AT’).

[0034] The condensation of the composite resin (A) and the tertiary amine (T) may be carried out by directly condensing the acid group of the composite resin (A) with the hydroxyalkyl group of the tertiary amine (T1) having a hydroxyalkyl group, or by condensing the hydroxyl group of the composite resin (A) with the hydroxyalkyl group of the tertiary amine (T1) having a hydroxyalkyl group via a dicarboxylic acid and / or a polyvalent carboxylic acid having a valence of 3 or more, or by directly condensing the hydroxyl group of the composite resin (A) with the carboxyalkyl group of the tertiary amine (T2) having a carboxyalkyl group. As the polyvalent carboxylic acid, the carboxylic acids listed as the carboxylic acid components of the polyester resin segment can be used, preferably a linear or branched aliphatic dicarboxylic acid, more preferably one or more selected from succinic acid, fumaric acid, and sebacic acid, and still more preferably fumaric acid. As a method for producing the condensate (AT’), preferably, it is a method of directly condensing the acid group of the composite resin (A) with the hydroxyalkyl group of the tertiary amine (T) having a hydroxyalkyl group.

[0035] Method for producing the composite resin (A) The composite resin (A) may be produced, for example, by a method including a step A of polycondensing an alcohol component and a carboxylic acid component, and a step B of addition-polymerizing a raw material monomer of the vinyl resin segment and a bifunctional monomer. Step B may be carried out after step A, step A may be carried out after step B, or step A and step B may be carried out simultaneously. In step A, a part of the carboxylic acid component is subjected to a polycondensation reaction, then after step B is carried out, the remainder of the carboxylic acid component is added to the polymerization system, and a method of further proceeding with the polycondensation reaction of step A and the polycondensation reaction with the carboxy groups of the bifunctional monomer or the structural sites derived from the bifunctional monomer is preferred.

[0036] In Project A, if necessary, esterification catalysts such as tin(II) bis(2-ethylhexanoate), dibutyltin oxide, and titanium diisopropoxybis(triethanolaminato) may be used in an amount of 0.001 parts by mass or more and 5 parts by mass or less based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component; esterification cocatalysts such as gallic acid (the same as 3,4,5-trihydroxybenzoic acid) may be used in an amount of 0.0001 parts by mass or more and 0.5 parts by mass or less based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component, and polycondensation may be carried out. When using a monomer having an unsaturated bond such as fumaric acid in the polycondensation, a radical polymerization inhibitor may be used, if necessary, preferably in an amount of 0.0001 parts by mass or more and 0.5 parts by mass or less based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component. Examples of the radical polymerization inhibitor include 4-tert-butylcatechol. The temperature of the polycondensation reaction is preferably 120 °C or higher, more preferably 130 °C or higher, still more preferably 140 °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.

[0037] Examples of the radical polymerization initiator for the addition polymerization in Project B include peroxides such as dibutyl peroxide, persulfates such as sodium persulfate, and azo compounds such as 2,2'-azobis(2,4-dimethylvaleronitrile). The amount of the radical polymerization initiator used is preferably 1 part by mass or more and 20 parts by mass or less based on 100 parts by mass of the raw material monomer of the vinyl-based resin segment. The temperature of the addition polymerization is preferably 110 °C or higher, more preferably 130 °C or higher, and preferably 230 °C or lower, more preferably 220 °C or lower, still more preferably 210 °C or lower.

[0038] The condensation of the acid group of the composite resin (A) and the tertiary amine (T1) having a hydroxyalkyl group can be carried out by heating these and removing the water generated by the dehydration reaction out of the system by means of reduced pressure or the like. When using a monomer having an unsaturated bond such as fumaric acid, a radical polymerization inhibitor may be used preferably in an amount of 0.0001 parts by mass or more and 0.5 parts by mass or less, based on 100 parts by mass of the total amount of the alcohol component and the carboxylic acid component, if necessary. Examples of the radical polymerization inhibitor include 4-tert-butylcatechol. The temperature of the condensation reaction is preferably 120 °C or higher, more preferably 130 °C or higher, still more preferably 140 °C or higher, and is preferably 250 °C or lower, more preferably 230 °C or lower, still more preferably 210 °C or lower. The condensation may be carried out in an inert gas atmosphere.

[0039] After obtaining the condensate (AT), it is preferable to include step 2 of steaming the reaction mixture containing the condensate (AT). By steaming the reaction mixture, unreacted tertiary amine (T) contained in the condensate can be efficiently removed. Steaming may be carried out by introducing steam into the reaction system, or may be carried out by generating steam in the reaction system by dropping ion-exchanged water into the reaction system. From the viewpoint of operational simplicity, it is preferable to generate steam in the reaction system by dropping ion-exchanged water into the reaction system. In order to efficiently separate the tertiary amine (T) from the reaction mixture, the supply amount of steam or ion-exchanged water is preferably 1 part by mass or more, more preferably 2 parts by mass or more, still more preferably 3 parts by mass or more, based on 100 parts by mass of the total amount of the condensate (AT). Also, from the viewpoint of simplifying the removal of moisture after steaming, the supply amount of steam or ion-exchanged water is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, still more preferably 6 parts by mass or less, based on 100 parts by mass of the total amount of the condensate (AT).

[0040] 〔Physical properties of condensate (AT)〕 The dielectric constant of the condensate (AT) is preferably 2.50×10 -13 / cm or more, more preferably 2.70×10 -13 / cm or more, still more preferably 2.80×10 -13 / cm or more, more preferably 2.85×10 -13 / cm or more, and preferably 3.40×10 -13 / cm or less, more preferably 3.20×10 -13 / cm or less, more preferably 3.10×10 -13 / cm or less, more preferably 3.05×10 -13 / cm or less.

[0041] From the viewpoint of improving charge transfer speed and improving thin line reproducibility in the condensate (AT), the charge transfer speed is preferably 0.020 or more, more preferably 0.025 or more, still more preferably 0.027 or more, and preferably 0.110 or less, more preferably 0.080 or less, still more preferably 0.050 or less.

[0042] The glass transition temperature of the condensate (AT) is preferably 30 °C or more, more preferably 35 °C or more, still more preferably 40 °C or more, and from the viewpoint of further improving low-temperature fixing property, it is preferably 80 °C or less, more preferably 70 °C or less, still more preferably 60 °C or less. The softening point of the condensate (AT) is preferably 70 °C or more, more preferably 80 °C or more, still more preferably 90 °C or more, and from the viewpoint of further improving low-temperature fixing property, it is preferably 150 °C or less, more preferably 140 °C or less, still more preferably 125 °C or less.

[0043] The acid value of the condensate (AT) is preferably 2 mgKOH / g or more, more preferably 3 mgKOH / g or more, still more preferably 5 mgKOH / g or more, and preferably 20 mgKOH / g or less, more preferably 15 mgKOH / g or less, still more preferably 13 mgKOH / g or less. The hydroxyl value of the condensate (AT) is preferably 20 mgKOH / g or more, more preferably 30 mgKOH / g or more, still more preferably 35 mgKOH / g or more, and preferably 60 mgKOH / g or less, more preferably 55 mgKOH / g or less, still more preferably 50 mgKOH / g or less. The amine value of the condensate (AT) is preferably 2 mg KOH / g or more, more preferably 4 mg KOH / g or more, still more preferably 6 mg KOH / g or more, and is preferably 20 mg KOH / g or less, more preferably 15 mg KOH / g or less, still more preferably 10 mg KOH / g or less.

[0044] The dielectric constant, charge transfer rate, glass transition temperature, softening point, acid value, hydroxyl value, and amine value of the condensate (AT) can be appropriately adjusted according to the types and amounts of the raw material monomers used, as well as production conditions such as reaction temperature, reaction time, and cooling rate. Moreover, these values are determined by the methods described in the examples. When two or more condensates (AT) are used in combination, it is preferable that the values of the dielectric constant, charge transfer rate, glass transition temperature, softening point, acid value, hydroxyl value, and amine value obtained as their mixture are respectively within the aforementioned ranges.

[0045] The toner binder resin composition of the present invention may further contain other resins such as the aforementioned composite resin (A) and the amorphous polyester resin (B) described below, as long as the effects of the present invention are not impaired. From the viewpoint of increasing the positive chargeability and improving the thin line reproducibility, the content of the condensate (AT) in the binder resin composition is preferably 25% by mass or more, more preferably 30% by mass or more, still more preferably 35% by mass or more, and is preferably 55% by mass or less, more preferably 50% by mass or less, still more preferably 45% by mass or less.

[0046] (Amorphous polyester resin (B)) The toner binder resin composition of the present invention may further contain an amorphous polyester resin (B) (hereinafter, also simply referred to as "resin (B)") from the viewpoint of improving the low-temperature fixability and hot offset resistance.

[0047] The resin (B) is preferably an amorphous polyester resin containing, for example, a polycondensate of an alcohol component and a carboxylic acid component. Examples of the polyester resin include a polyester resin and a modified polyester resin. Examples of the modified polyester resin include a urethane-modified polyester resin and an epoxy-modified polyester resin. Among these, an amorphous polyester resin which is a polycondensate of an alcohol component and a carboxylic acid component is preferable.

[0048] Examples of the alcohol component include an alkylene oxide adduct of an aromatic diol, a linear or branched aliphatic diol, an alicyclic diol, and a polyhydric alcohol having a valence of 3 or more, which are the same as the alcohol component of the polyester resin segment of the composite resin (A) described above. Among these, from the viewpoint of obtaining a toner excellent in low-temperature fixability, an alkylene oxide adduct of an aromatic diol is preferable, more preferably an alkylene oxide adduct of bisphenol A, still more preferably a propylene oxide adduct of bisphenol A [2,2-bis(4-hydroxyphenyl)propane] or an ethylene oxide adduct of bisphenol A. These may be used alone or in combination of two or more.

[0049] Examples of the carboxylic acid component include a dicarboxylic acid and a polyhydric carboxylic acid having a valence of 3 or more. Examples of the dicarboxylic acid include the same dicarboxylic acids as the carboxylic acid component of the polyester resin segment described above, such as aromatic dicarboxylic acids, linear or branched aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids. Among these, at least one selected from aromatic dicarboxylic acids and linear or branched aliphatic dicarboxylic acids is preferable. The amount of the aromatic dicarboxylic acid is preferably 40 mol% or more, more preferably 50 mol% or more, still more preferably 60 mol% or more, and preferably 95 mol% or less, more preferably 85 mol% or less, still more preferably 75 mol% or less in the carboxylic acid component. Examples of the polyhydric carboxylic acid having a valence of 3 or more include the same polyhydric carboxylic acids having a valence of 3 or more as the carboxylic acid component of the polyester resin segment described above.

[0050] The amount of the linear or branched aliphatic dicarboxylic acid is preferably 1 mol% or more, more preferably 3 mol% or more, still more preferably 5 mol% or more in the carboxylic acid component, and is preferably 60 mol% or less, more preferably 30 mol% or less, still more preferably 20 mol% or less.

[0051] When a polyvalent carboxylic acid having a valence of 3 or more is included, the amount of the polyvalent carboxylic acid having a valence of 3 or more is preferably 3 mol% or more, more preferably 5 mol% or more, still more preferably 8 mol% or more in the carboxylic acid component, and is preferably 30 mol% or less, more preferably 25 mol% or less, still more preferably 20 mol% or less. These carboxylic acid components may be used alone or in combination of two or more.

[0052] The equivalent ratio of the carboxy group of the carboxylic acid component to the hydroxy group of the alcohol component [COOH group / OH group] is preferably 0.7 or more, more preferably 0.8 or more, and is preferably 1.3 or less, more preferably 1.2 or less.

[0053] The resin (B) may be produced, for example, by the step A of polycondensing an alcohol component and a carboxylic acid component. The step A is the same as the step A described in the production method of the composite resin (A), and the preferable range is also the same.

[0054] [[Physical properties of the amorphous polyester resin (B)]] The glass transition temperature of the resin (B) is preferably 30°C or more, more preferably 40°C or more, still more preferably 50°C or more, and from the viewpoint of further improving the low-temperature fixing property, it is preferably 90°C or less, more preferably 80°C or less, still more preferably 70°C or less. The softening point of the resin (B) is preferably 70°C or more, more preferably 90°C or more, still more preferably 100°C or more, and from the viewpoint of further improving the low-temperature fixing property, it is preferably 160°C or less, more preferably 150°C or less, still more preferably 145°C or less.

[0055] The acid value of resin (B) is preferably 1 mg KOH / g or more, more preferably 2 mg KOH / g or more, still more preferably 3 mg KOH / g or more, and is preferably 20 mg KOH / g or less, more preferably 15 mg KOH / g or less, still more preferably 10 mg KOH / g or less. The hydroxyl value of resin (B) is preferably 20 mg KOH / g or more, more preferably 25 mg KOH / g or more, still more preferably 30 mg KOH / g or more, and is preferably 50 mg KOH / g or less, more preferably 45 mg KOH / g or less, still more preferably 40 mg KOH / g or less. The glass transition temperature, softening point, acid value, and hydroxyl value of resin (B) can be appropriately adjusted according to the types and amounts of raw material monomers used, as well as production conditions such as reaction temperature, reaction time, and cooling rate. Moreover, those values are determined by the methods described in the examples. In addition, when two or more kinds of resin (B) are used in combination, it is preferable that the values of the glass transition temperature, softening point, acid value, and hydroxyl value obtained as their mixture are respectively within the aforementioned ranges.

[0056] The content of resin (B) in the binder resin composition is preferably 35% by mass or more, more preferably 40% by mass or more, still more preferably 45% by mass or more, and is preferably 65% by mass or less, more preferably 60% by mass or less, still more preferably 55% by mass or less.

[0057] (Crystalline polyester resin (C)) From the viewpoint of improving low-temperature fixability, the binder resin composition for toner of the present invention preferably contains a crystalline polyester resin (C) (hereinafter, also simply referred to as "resin (C)").

[0058] Resin (C) is, for example, a crystalline polyester resin that is a polycondensate of an alcohol component and a carboxylic acid component. As the alcohol component, α,ω-aliphatic diol is preferable. The number of carbon atoms of the α,ω-aliphatic diol is preferably 2 or more, more preferably 4 or more, still more preferably 6 or more, and preferably 16 or less, more preferably 14 or less, still more preferably 12 or less. Examples of the α,ω-aliphatic diol include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol. Among these, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol are preferred, and 1,6-hexanediol is more preferred.

[0059] The amount of the α,ω-aliphatic diol in the alcohol component is preferably 80 mol% or more, more preferably 85 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more, and 100 mol% or less, and still more preferably 100 mol%.

[0060] The alcohol component may contain other alcohol components different from the α,ω-aliphatic diol. Examples of the other alcohol components include aliphatic diols other than α,ω-aliphatic diols such as 1,2-propanediol and neopentyl glycol; aromatic diols such as alkylene oxide adducts of bisphenol A; and polyhydric alcohols having 3 or more valences such as glycerin, pentaerythritol, and trimethylolpropane. These alcohol components may be used alone or in combination of two or more.

[0061] As the carboxylic acid component, an aliphatic dicarboxylic acid is preferred, and a linear aliphatic dicarboxylic acid is more preferred. The number of carbon atoms of the aliphatic dicarboxylic acid is preferably 4 or more, and preferably 14 or less, more preferably 12 or less. Examples of the aliphatic dicarboxylic acid include fumaric acid, sebacic acid, dodecanedioic acid, and tetradecanedioic acid. Among these, fumaric acid, sebacic acid, and tetradecanedioic acid are preferred, and fumaric acid is more preferred. These carboxylic acid components may be used alone or in combination of two or more.

[0062] The amount of the aliphatic dicarboxylic acid is preferably 80 mol% or more, more preferably 85 mol% or more, still more preferably 90 mol% or more, and even more preferably 95 mol% or more, and is 100 mol% or less, and more preferably 100 mol% in the carboxylic acid component.

[0063] The carboxylic acid component may contain other carboxylic acid components different from the aliphatic dicarboxylic acid. Examples of the other carboxylic acid components include aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid; polyvalent carboxylic acids having a valence of 3 or more. These carboxylic acid components may be used alone or in combination of two or more.

[0064] The equivalent ratio of the carboxy group of the carboxylic acid component to the hydroxy group of the alcohol component [COOH group / OH group] is preferably 0.7 or more, more preferably 0.8 or more, and is preferably 1.3 or less, more preferably 1.2 or less.

[0065] The resin (C) may be produced, for example, by step A of polycondensing an alcohol component and a carboxylic acid component. Step A is the same as step A described in the production method of the composite resin (A), and the preferred range is the same except for the temperature of the polycondensation reaction. The temperature of the polycondensation reaction in the production method of the resin (C) is preferably 110°C or more, more preferably 120°C or more, still more preferably 130°C or more, and is preferably 250°C or less, more preferably 240°C or less, and still more preferably 230°C or less. The polycondensation may be carried out in an inert gas atmosphere.

[0066] [Physical properties of the crystalline polyester resin (C)] The softening point of resin (C) is preferably 60°C or higher, more preferably 70°C or higher, still more preferably 80°C or higher, from the viewpoint of the storage stability of the toner, and is preferably 150°C or lower, more preferably 140°C or lower, still more preferably 130°C or lower, from the viewpoint of further improving the low-temperature fixability. The melting point of resin (C) is preferably 60°C or higher, more preferably 70°C or higher, still more preferably 80°C or higher, from the viewpoint of the storage stability of the toner, and is preferably 150°C or lower, more preferably 140°C or lower, still more preferably 130°C or lower, from the viewpoint of further improving the low-temperature fixability.

[0067] The acid value of resin (C) is preferably 1 mgKOH / g or higher, more preferably 2 mgKOH / g or higher, still more preferably 3 mgKOH / g or higher, and is preferably 20 mgKOH / g or lower, more preferably 15 mgKOH / g or lower, still more preferably 10 mgKOH / g or lower.

[0068] The softening point, melting point, and acid value of resin (C) can be appropriately adjusted according to the type and amount of the raw material monomers used, and the manufacturing conditions such as the reaction temperature, reaction time, and cooling rate, and are determined by the method described in the examples below. When two or more kinds of resin (C) are used in combination, it is preferable that the values of the softening point, melting point, and acid value obtained as a mixture thereof are within the above ranges, respectively.

[0069] The content of resin (C) in the binder resin composition for toner is preferably 3% by mass or higher, more preferably 5% by mass or higher, still more preferably 8% by mass or higher, and is preferably 20% by mass or lower, more preferably 18% by mass or lower, still more preferably 15% by mass or lower.

[0070] [Electrophotographic toner] The electrophotographic toner of the present invention (hereinafter, also referred to as "the toner of the present invention") contains the binder resin composition for toner, and preferably contains a colorant and the binder resin composition for toner. The toner of the present invention contains, for example, toner mother particles and external additives. The toner mother particles contain the binder resin composition for toner, and preferably contain a colorant and the binder resin composition for toner. And the toner mother particles may contain, for example, a colorant derivative, a charge control agent, a release agent such as wax, and other additives. From the viewpoint of increasing the positive chargeability of the toner and improving the fine line reproducibility, the content of the binder resin composition for toner is preferably 60% by mass or more, more preferably 65% by mass or more, still more preferably 70% by mass or more in the toner mother particles, and preferably 90% by mass or less, more preferably 85% by mass or less, still more preferably 80% by mass or less.

[0071] 〔Colorant〕 In the present invention, the toner mother particles preferably contain a colorant. As the colorant, all dyes, pigments, etc. used as colorants for toner can be used. Examples of the colorant include carbon black, phthalocyanine blue (e.g., pigment blue 15:3), permanent brown FG, brilliant fast scarlet, pigment green B, rhodamine-B base, solvent red 49, solvent red 146, solvent blue 35, quinacridone, carmine 6B, and disazo yellow. The toner may be either a black toner or a color toner other than black. The content of the colorant is preferably 1% by mass or more, more preferably 3% by mass or more in the toner mother particles, and preferably 25% by mass or less, more preferably 20% by mass or less, still more preferably 15% by mass or less.

[0072] 〔Release agent〕 In the present invention, the toner mother particles preferably contain a release agent. Examples of the release agent include hydrocarbon waxes such as polypropylene wax, polyethylene wax, polypropylene-polyethylene copolymer wax, microcrystalline wax, paraffin wax, Fischer-Tropsch wax, and Sasol wax, or their oxides; ester waxes such as carnauba wax, montan wax, or their deacidified waxes, and fatty acid ester waxes; fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts. These may be used alone or in combination of two or more.

[0073] The melting point of the release agent is preferably 60°C or higher, more preferably 70°C or higher, and preferably 160°C or lower, more preferably 140°C or lower, still more preferably 120°C or lower, and even more preferably 100°C or lower. The content of the release agent in the toner mother particles is preferably 0.1% by mass or more, more preferably 1% by mass or more, still more preferably 2% by mass or more, and even more preferably 3% by mass or more, and preferably 20% by mass or less, more preferably 15% by mass or less, and still more preferably 10% by mass or less.

[0074] [Charge control agent] The toner of the present invention may contain a charge control agent. The charge control agent may contain either a positively chargeable charge control agent or a negatively chargeable charge control agent. Among these, a positively chargeable charge control agent is preferred. Examples of positive charge control agents include nigrosine dyes such as "Nigrosine Base EX", "Oil Black BS", "Oil Black SO", "Bontron® N-01", "Bontron® N-04", "Bontron® N-07", "Bontron® N-09", "Bontron® N-11" (manufactured by Orient Chemical Industries, Ltd.); triphenylmethane dyes containing a tertiary amine in the side chain, quaternary ammonium salt compounds such as "Bontron® P-51" (manufactured by Orient Chemical Industries, Ltd.), cetyltrimethylammonium bromide, "COPY CHARGE PX VP435" (manufactured by Clariant); polyamine resins such as "AFP-B" (manufactured by Orient Chemical Industries, Ltd.); imidazole derivatives such as "PLZ-2001", "PLZ-8001" (manufactured by Shikoku Kasei Kogyo Co., Ltd.); styrene-acrylic resins such as "FCA-701PT", "FCA-201-PS" (manufactured by Fujikura Kasei Co., Ltd.) and the like.

[0075] Examples of negative charge control agents include metal-containing azo dyes such as "Valifast® Black 3804", "Bontron® S-31", "Bontron® S-32", "Bontron® S-34", "Bontron® S-36" (manufactured by Orient Chemical Industries, Ltd.), "Eisenspirone Black TRH", "T-77" (manufactured by Hodogaya Chemical Co., Ltd.); metal compounds of benzoic acid compounds such as "LR-147", "LR-297" (manufactured by Nippon Carlit Co., Ltd.); metal compounds of salicylic acid compounds such as "Bontron® E-81", "Bontron® E-84", "Bontron® E-88", "Bontron E-304" (manufactured by Orient Chemical Industries, Ltd.), "TN-105" (manufactured by Hodogaya Chemical Co., Ltd.); copper phthalocyanine dyes; quaternary ammonium salts such as "COPY CHARGE PX VP434" (manufactured by Clariant), nitroimidazole derivatives; organometallic compounds and the like. These charge control agents may be used alone or in combination of two or more.

[0076] The content of the charge control agent is preferably 1 part by mass or more, more preferably 5 parts by mass or more, still more preferably 10 parts by mass or more, and preferably 25 parts by mass or less, more preferably 20 parts by mass or less, still more preferably 18 parts by mass or less, based on 100 parts by mass of the total amount of the binder resin component of the toner.

[0077] 〔Other Additives〕 The toner mother particles may further appropriately contain additives such as magnetic powder, fluidity improvers, conductivity adjusters, reinforcing fillers such as fibrous substances, antioxidants, anti-aging agents, and cleaning property improvers as other additives.

[0078] In the toner of the present invention, the content of the toner mother particles is preferably 80% by mass or more, more preferably 90% by mass or more, still more preferably 95% by mass or more, and 100% by mass or less, preferably 99% by mass or less.

[0079] The volume median particle diameter (D 50 ) is preferably 2 μm or more, more preferably 3 μm or more, still more preferably 4 μm or more, and preferably 20 μm or less, more preferably 15 μm or less, still more preferably 10 μm or less. In this specification, the volume median particle diameter (D 50 ) means the particle diameter at which the cumulative volume frequency calculated by volume fraction becomes 50% when calculated from the smaller particle diameter side.

[0080] 〔External Additives〕 The toner of the present invention may further contain an external additive in order to improve fluidity. Examples of the external additive include fine particles of inorganic materials such as silica, alumina, titania, zirconia, tin oxide, and zinc oxide, and organic fine particles such as melamine resin fine particles and polytetrafluoroethylene resin fine particles. These may be used alone or in combination of two or more. Among these external additives, silica is preferred, and hydrophobic silica treated with a hydrophobizing agent is more preferred.

[0081] Examples of the hydrophobing agent include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane (OTES), and methyltriethoxysilane. Among these, hexamethyldisilazane is preferred.

[0082] When the surface treatment of toner mother particles is carried out using an external additive, the content of the external additive in the toner of the present invention is preferably 0.5 parts by mass or more, more preferably 0.8 parts by mass or more, still more preferably 1 part by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts by mass or less, still more preferably 4 parts by mass or less, based on 100 parts by mass of the toner mother particles, from the viewpoints of the chargeability and fluidity of the toner.

[0083] The toner of the present invention may be a toner obtained by any known method such as a melt-kneading method, an emulsion phase inversion method, a suspension polymerization method, or an emulsion aggregation method. However, from the viewpoints of productivity and dispersibility of the colorant, a pulverized toner obtained by the melt-kneading method is preferred. In the melt-kneading method, after uniformly dispersing the binder resin composition for toner, a colorant, and, if necessary, a property improver such as a release agent, etc., melt-kneading, cooling, pulverizing, and classifying are carried out by a known method to obtain a toner having a volume median particle diameter (D 50 ) of 2 μm or more and 20 μm or less.

[0084] The toner of the present invention is used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, etc. The toner can be used as a one-component developer or mixed with a carrier to be used as a two-component developer.

Examples

[0085] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited by these examples. The physical properties of resins, etc. were measured by the following methods.

[0086] [Measurement] [Softening point, crystallinity index, melting point, glass transition temperature of resin] (1) Softening point Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), while heating 1 g of the sample at a heating rate of 6 °C / min, 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. With respect to the temperature, the plunger descent amount of the flow tester was plotted, and the temperature at which half of the sample flowed out was defined as the softening point.

[0087] (2) Crystallinity index Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan and cooled to 0 °C at a cooling rate of 10 °C / min. Then the sample was left stationary for 1 minute as it was, and thereafter, the temperature was raised to 180 °C at a heating rate of 10 °C / min and the heat quantity was measured. Among the observed endothermic peaks, the temperature of the peak with the largest peak area was defined as the maximum peak temperature (1) of the endotherm, and the crystallinity index was determined by (softening point (°C)) / (maximum peak temperature (1) of the endotherm (°C)).

[0088] (3) Melting point and glass transition temperature Using a differential scanning calorimeter "Q100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample was weighed into an aluminum pan, the temperature was raised to 200 °C, and then cooled to 0 °C at a cooling rate of 10 °C / min from that temperature. Then the sample was heated at a heating rate of 10 °C / min and the heat quantity was measured. Among the observed endothermic peaks, the temperature of the peak with the largest peak area was defined as the maximum peak temperature (2) of the endotherm. In the case of a crystalline resin, the peak temperature was defined as the melting point. Also, when a peak was observed in the case of an amorphous resin, the temperature of the peak was taken as the glass transition temperature, and when no peak was observed but a step was observed, the temperature of the intersection of the tangent line showing the maximum slope of the curve of the step portion and the extension line of the baseline on the low temperature side of the step was taken as the glass transition temperature.

[0089] [Acid value and hydroxyl value of the resin] Measured in accordance with JIS K0070:1992. However, chloroform was used as the measurement solvent.

[0090] [Amine value of the resin] Accurately weigh 1.0 to 1.5 g of the sample into a 150 mL beaker, add approximately 70 mL of ethyl alcohol to dissolve it to obtain a sample solution. Add 2 to 3 drops of phenolphthalein indicator solution to the sample solution, and add 10% by mass sodium hydroxide solution to make it weakly alkaline. Using a potentiometric titration apparatus, titrate with 0.2 mol / L alcoholic hydrochloric acid standard solution until after the first equivalence point and the second equivalence point. Then, calculate the amine value according to the following formula 1.

[0091]

Number

[0092] In formula 1, A, B, and f are as follows. A: The amount (mL) of 0.2 mol / L alcoholic hydrochloric acid standard solution used for titration up to the first equivalence point B: The amount (mL) of 0.2 mol / L alcoholic hydrochloric acid standard solution used for titration up to the second equivalence point f: The factor of 0.2 mol / L alcoholic hydrochloric acid standard solution

[0093] 〔Dielectric constant〕 Weigh 3 g of the resin sample and melt-press it at 75 °C and 20 MPa using a hot press machine to produce disk-shaped resin pellets. Then, measure the dielectric constant with a dielectric measurement electrode "Agilent 16451B" (manufactured by Agilent Technologies).

[0094] 〔Charge transfer rate〕 Weigh 0.1 g of the resin sample and dissolve it in 5 mL of chloroform. Drop 0.2 mL of the chloroform solution of the resin into an aluminum disk-shaped container with a diameter of 13 mm (manufactured by Nano Seeds Co., Ltd.: NS-D series sample pan for measuring electrostatic diffusion rate), and dry it at room temperature under a nitrogen stream to obtain a measurement sample. Measure the surface of the measurement sample with a surface potentiometer (manufactured by Nano Seeds Co., Ltd.: electrostatic diffusion rate measurement device NS-D100) to obtain the charge transfer rate.

[0095] 〔Volume median diameter D of toner mother particles 50 〕 Volume median diameter D of toner mother particles50 It was measured as follows. · Measuring instrument: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter, Inc.) · Aperture diameter: 50 μm · Analysis software: "Multisizer (registered trademark) III Version 3.51" (manufactured by Beckman Coulter, Inc.) · Electrolyte: "Isoton (registered trademark) II" (manufactured by Beckman Coulter, Inc.) · Dispersion liquid: Polyoxyethylene lauryl ether "Emulgen (registered trademark) 109P" (manufactured by Kao Corporation, HLB: 13.6) was dissolved in the electrolyte to obtain a dispersion liquid with a concentration of 5% by mass. · Dispersion conditions: 10 mg of toner measurement sample was added to 5 mL of the dispersion liquid, and dispersed with an ultrasonic disperser for 1 minute. Then, 25 mL of the electrolyte was added, and further dispersed with an ultrasonic disperser for 1 minute to prepare a sample dispersion liquid. · Measurement conditions: By adding the sample dispersion liquid to 100 mL of the electrolyte, the concentration was adjusted to a concentration at which the particle sizes of 30,000 particles could be measured in 20 seconds. Then, 30,000 particles were measured, and the volume median diameter D 50 was determined.

[0096] [Manufacture of resin] Production Example A1 (Condensate AT'-1) 3,535 g of a propylene oxide (2.2) adduct of bisphenol A and 1,407 g of an ethylene oxide (2.2) adduct of bisphenol A were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a dehydrating tube, a stirrer, and a thermocouple. After heating to 100°C, 1,880 g of terephthalic acid was added, and the temperature was raised to 160°C. While maintaining the temperature at 160°C, a mixture of 1,592 g of styrene, 42 g of acrylic acid, and 64 g of dibutyl peroxide was added dropwise over 1 hour, and after reacting for 60 minutes, the temperature was raised to 200°C. Further, the pressure inside the flask was reduced, and a pressure-reducing reaction was carried out at 8 kPa for 1 hour. Thereafter, 35 g of tin(II) bis(2-ethylhexanoate) and 3.5 g of gallic acid were added, the temperature was raised to 235°C, and the reaction was carried out at 235°C for 8 hours. Thereafter, the mixture was cooled to 150°C, 193 g of fumaric acid, 3.5 g of 4-tert-butylcatechol, and 169 g of 3-dimethylamino-1-propanol were added, the temperature was raised to 160°C, and the reaction was carried out for 1 hour. Thereafter, the temperature was raised to 200°C at 10°C / h, 350 g of ion-exchanged water was added dropwise over 1 hour, and steaming was carried out. Thereafter, the pressure inside the flask was reduced, and a pressure-reducing reaction was carried out at 8 kPa for 1 hour to obtain a condensate AT’-1.

[0097] Production Examples A2 and A3 (Condensates AT’-2 and AT’-3) In Production Example A1, condensates AT’-2 and AT’-3 were obtained in the same manner as in Production Example A1, except that 3-dimethylamino-1-propanol was changed to the tertiary amine shown in Table 1.

[0098] Production Example A4 (Condensate AT’-4) In Production Example A1, condensate AT’-4 was obtained in the same manner as in Production Example A1, except that steaming was not carried out.

[0099] Production Example A5 (Resin A-1) 3,607 g of a propylene oxide (2,2) adduct of bisphenol A and 1,436 g of an ethylene oxide (2,2) adduct of bisphenol A were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a dehydrating tube, a stirrer, and a thermocouple. After heating to 100°C, 1,919 g of terephthalic acid was added, and the temperature was raised to 160°C. While maintaining the temperature at 160°C, a mixture of 1,624 g of styrene, 42 g of acrylic acid, and 65 g of dibutyl peroxide was added dropwise over 1 hour. After reacting for 60 minutes, the temperature was raised to 200°C, and the pressure inside the flask was further reduced. A pressure-reducing reaction was carried out at 8 kPa for 1 hour. Then, 36 g of tin(II) bis(2-ethylhexanoate) and 3.6 g of gallic acid were added, and the temperature was raised to 235°C. The reaction was carried out at 235°C for 8 hours. Then, it was cooled to 150°C, 196 g of fumaric acid and 3.6 g of 4-tert-butylcatechol were added, and the temperature was raised to 160°C and reacted for 1 hour. Then, the temperature was raised to 200°C at a rate of 10°C / h. Then, the pressure inside the flask was reduced, and a pressure-reducing reaction was carried out at 8 kPa for 1 hour to obtain composite resin A-1.

[0100] Production Example A6 (Resin A-2) In Production Example A5, 350 g of ion-exchanged water was added dropwise over 1 hour and steaming was carried out. Otherwise, in the same manner as in Production Example A5, composite resin A-2 was obtained.

[0101] [Table 1] *1: BPA-PO means a polyoxypropylene (2,2) adduct of bisphenol A. BPA-EO means a polyoxyethylene (2,2) adduct of bisphenol A. *2: When the alcohol component of the raw material monomer of the polyester resin segment is 100 mol parts, it means the mol parts of the raw material monomer and each monomer constituting both reactive monomers. *3: It means the content (mass%) of each monomer constituting the raw material monomer in the total amount of the vinyl resin segment. *4: When the total amount of the vinyl resin segment is 100 mass parts, it means the addition amount (mass parts) of the polymerization initiator. *5: It means the content (mass %) of the tertiary amine (T) in the total amount of the condensate (AT’). *6: It means the addition amount (parts by mass) of ion-exchanged water when the total amount of the condensate (AT’) is 100 parts by mass. *7: It means the content (mass %) of the vinyl-based resin segment with respect to the total amount of the polyester resin segment and the vinyl-based resin segment.

[0102] Production Example B (Resin B-1) 4477 g of the propylene oxide (2.2) adduct of bisphenol A and 1782 g of the ethylene oxide (2.2) adduct of bisphenol A were placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a dehydrating tube, a stirrer, and a thermocouple. After heating to 160°C, 1699 g of terephthalic acid, 481 g of trimellitic acid, 561 g of 2-dodecene-1-yl succinic anhydride, and 45 g of tin(II) bis(2-ethylhexanoate) were added, and the temperature was raised to 235°C and reacted at 235°C for 7 hours. Then, the pressure in the flask was reduced, and a decompression reaction was carried out at 8 kPa for 1 hour to obtain Resin B-1 as an amorphous polyester resin.

[0103]

Table 2

[0104] Production Example C (Resin C-1) 4539 g of 1,6-hexanediol was placed in a 10-liter four-necked flask equipped with a nitrogen inlet tube, a dehydrating tube, a stirrer, and a thermocouple. After heating to 100°C, 4462 g of fumaric acid, 18 g of tin(II) bis(2-ethylhexanoate), and 4.5 g of 4-tert-butylcatechol were added, and the temperature was raised to 140°C. After reacting for 1 hour, the temperature was raised to 150°C and reacted for 1 hour. The temperature was raised to 200°C at 10°C / h and reacted at 8.0 kPa for 3 hours to obtain Resin C-1 as a crystalline polyester resin.

[0105]

Table 3

[0106] [Manufacture of Toner] Examples 1 to 4 and Comparative Examples 1 and 2 40 parts by mass of the condensates AT'-1 to 4, resin A-1, or resin A-2 shown in Table 4, 50 parts by mass of resin B-1 as an amorphous polyester resin, 10 parts by mass of resin C-1 as a crystalline polyester resin, 6 parts by mass of a colorant "ECB-301" (manufactured by Dainichi Seika Kogyo Co., Ltd.), 7 parts by mass of a release agent "HNP-9" (manufactured by Nippon Seiro Co., Ltd.), and 15 parts by mass of a positive charge control agent "FCA-201-PS" (manufactured by Fujikura Kasei Co., Ltd.) were stirred using a Henschel mixer at a rotational speed of 1500 r / min (peripheral speed 21.6 m / sec) for 3 minutes, and then melt-kneaded using a co-rotating twin-screw extruder (manufactured by Ikegai Corporation, product name: PCM-30, shaft diameter 2.9 cm, shaft cross-sectional area 7.06 cm 2 ). The rotational speed of the roll was 200 r / min (peripheral speed 0.30 m / sec), the barrel set temperature was 1000 °C, and the supply rate of the kneaded product was 10 kg / h (mixture supply amount per unit cross-sectional area of the shaft 1.42 kg / h·cm 2 ).

[0107] The obtained kneaded product was rolled and cooled with a cooling roll, and then roughly pulverized to about 1 mm using a hammer mill. The obtained roughly pulverized product was finely pulverized and classified by an air jet mill (manufactured by Nippon Pneumatic Co., Ltd., product name: IDS), and toner mother particles with a volume median diameter (D 50 ) of 7.0 μm were obtained. 100 parts by mass of the obtained toner mother particles, 0.5 parts by mass of hydrophobic silica "TG-820F" (manufactured by Cabot Specialty Chemicals Inc., number average particle diameter: 8 nm) as an external additive, 2.0 parts by mass of hydrophobic silica "NA-50Y" (manufactured by Nippon Aerosil Co., Ltd., number average particle diameter: 30 nm), and 0.4 parts by mass of polytetrafluoroethylene fine particles "KTL-500F" (manufactured by Kitamura Co., Ltd., number average particle diameter: 500 nm) were mixed using a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.) at 2100 r / min (peripheral speed 29 m / sec) for 3 minutes to obtain toner.

[0108] [Image quality evaluation] [Thin line reproducibility] The toner obtained above was mounted on a non-magnetic one-component developing device (manufactured by Brother Industries, Ltd., product name: HL-2040), and a 1dot / 3space / horizontal line pattern was printed in an environment of 25°C and 50% relative humidity. The reproducibility of a 1dot line was confirmed with a digital microscope (manufactured by Olympus Corporation, product name: DSX510, using a 50x lens, observation conditions: 693 times), and the thin line reproducibility was evaluated according to the following criteria A to D. If it is above criterion B, the image quality is excellent. The results are shown in Table 4. A: There are 5 or fewer breaks in a 1dot line (1 line / cm). B: There are 6 or more and 12 or fewer breaks in a 1dot line (1 line / cm). C: There are 13 or more and 20 or fewer breaks in a 1dot line (1 line / cm). D: There are 21 or more breaks in a 1dot line (1 line / cm).

[0109] [Table 4]

[0110] From the results of the examples and comparative examples, it was found that the toner using the binder resin composition for toner of the present invention is excellent in thin line reproducibility and improves the image quality of printed matter. This is considered to be due to the increase in the positive chargeability because the dielectric constant and the charge transfer rate of the condensate (AT) contained in the binder resin composition for toner of the present invention have been improved.

Claims

1. A toner binder resin composition containing a condensate (AT) of a polyester resin segment, which is a polycondensate of a carboxylic acid component containing 80 mol% or more of an alcohol component and an aromatic dicarboxylic acid, a vinyl resin segment, which is an addition polymer of a raw material monomer containing a styrene-based compound, and a tertiary amine (T1) having a hydroxyalkyl group, wherein the condensate (AT) is a condensate (AT') of a composite resin (A) containing the polyester resin segment and the vinyl resin segment and the tertiary amine (T1), and the condensate (AT') is a condensate of a polyester resin segment and the tertiary amine (T1).

2. The toner binder resin composition according to claim 1, wherein the content of the styrene-based compound in the raw material monomer of the vinyl resin segment is 70% by mass or more.

3. The toner binder resin composition according to claim 1 or 2, wherein the content of the vinyl resin segment in the condensate (AT) is 5% by mass or more and 30% by mass or less.

4. The toner binder resin composition according to any one of claims 1 to 3, wherein the condensate (AT) contains 0.5% by mass or more and 5% by mass or less of structural units derived from the tertiary amine (T1).

5. The toner binder resin composition according to any one of claims 1 to 4, wherein the amine value of the condensate (AT) is 2 mgKOH / g or more and 20 mgKOH / g or less.

6. An electrophotographic toner containing the toner binder resin composition according to any one of claims 1 to 5.

7. A method for producing the toner binder resin composition according to any one of claims 1 to 5, including the following steps 1 and 2. Step 1: A step of condensing a polyester resin segment, a vinyl resin segment, and a tertiary amine (T1) to obtain a reaction mixture containing a condensate (AT). Step 2: A step of steaming the reaction mixture obtained in Step 1.

Images