JP2011039233A - Electrophotographic toner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide electrophotographic toner having sufficient low temperature fixability and storage property and excellent rising property of charging, and to provide a binder resin for toner and a crystalline resin for toner to be used for the toner. <P>SOLUTION: The binder resin for the electrophotographic toner contains an amorphous resin and a crystalline resin, wherein both of the amorphous resin and the crystalline resin are formed of a condensation-polymerization resin obtained by condensing and polymerizing an alcohol component and a carboxylic acid component. At least either the amorphous resin or the crystalline resin is a resin obtained by using an aromatic compound represented by formula (I) as a carboxylic acid component and/or an alcohol component. The electrophotographic toner contains the above binder resin. The binder resin is obtained by using an aromatic compound represented by formula (I) as a carboxylic acid component and/or an alcohol component. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electrophotographic toner used for developing a latent image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method, and the like, and a binder resin and a crystalline resin used for the toner.

  In recent years, with an increase in machine speed and energy saving, a toner having excellent low-temperature fixability has been demanded. Therefore, a toner binder resin containing a crystalline polyester and an amorphous polyester resin has been proposed as a toner binder resin.

  Patent Document 1 discloses a toner binder resin containing a crystalline polyester and an amorphous polyester resin as a toner binder resin having excellent low-temperature fixability, environmental stability, and blocking resistance. The crystalline polyester is obtained by polycondensing an alcohol component containing 70 mol% or more of an aliphatic diol having 2 to 8 carbon atoms and a carboxylic acid component containing 70 mol% or more of an aromatic dicarboxylic acid compound. A binder resin for toner is disclosed.

  Patent Document 2 discloses a crystalline polyester for toner and a non-binding resin as a binder resin for toner that has not only low-temperature fixability and chargeability but also excellent mechanical strength and excellent durability even in a non-magnetic one-component development system. A binder resin for toner comprising a crystalline resin, wherein the crystalline polyester for toner comprises 70 mol% of an alcohol component containing 70 mol% or more of 1,6-hexanediol and an aromatic carboxylic acid compound. A polyester obtained by condensation polymerization of the carboxylic acid component contained above is disclosed.

JP-A-2005-300867 JP 2005-321747 A

  However, a binder resin using a crystalline resin and an amorphous resin is excellent in toner low-temperature fixability and storability, but has insufficient charge rising properties.

  An object of the present invention is to provide an electrophotographic toner, a binder resin for toner and a crystalline resin for toner used in the toner, which satisfy both low temperature fixability and storage stability and are excellent in charge rising property. It is in.

The present invention
[1] A binder resin for an electrophotographic toner comprising an amorphous resin and a crystalline resin, wherein each of the amorphous resin and the crystalline resin comprises an alcohol component and a carboxylic acid component. A condensation polymerization resin obtained by condensation polymerization, wherein at least one of the amorphous resin and the crystalline resin is represented by the formula (I):

(Wherein R ¹ represents a hydrogen atom, a hydroxyl group or a methoxy group, and X represents a hydroxyl group or a carboxyl group which may have a hydrogen atom, an aldehyde group, an allyl group, a vinyl group, a methoxy group or a linking group. Show.)
A binder resin for an electrophotographic toner, which is a resin obtained by using an aromatic compound represented by the following as a carboxylic acid component and / or an alcohol component:
[2] An electrophotographic toner comprising the binder resin according to [1], and [3] Formula (I):

(Wherein R ¹ represents a hydrogen atom, a hydroxyl group or a methoxy group, and X represents a hydroxyl group or a carboxyl group which may have a hydrogen atom, an aldehyde group, an allyl group, a vinyl group, a methoxy group or a linking group. Show.)
The crystalline resin for electrophotographic toner obtained by using the aromatic compound represented by these as a carboxylic acid component and / or an alcohol component.

  The electrophotographic toner containing the binder resin of the present invention is excellent in charge rising property while satisfying low-temperature fixability and storage stability.

  The binder resin for an electrophotographic toner of the present invention contains an amorphous resin and a crystalline resin, both of which are condensation polymerization resins obtained by condensation polymerization of an alcohol component and a carboxylic acid component. And at least one of the amorphous resin and the crystalline resin has the formula (I):

(Wherein R ¹ represents a hydrogen atom, a hydroxyl group or a methoxy group, and X represents a hydroxyl group or a carboxyl group which may have a hydrogen atom, an aldehyde group, an allyl group, a vinyl group, a methoxy group or a linking group. Show.)
In that it is a resin obtained by using the aromatic compound as a carboxylic acid component and / or an alcohol component. Exhibits excellent charge rise without sacrificing storage. The binder resin of the present invention is excellent in charge rising property because, in the resin, excessive compatibility between the crystalline resin and the amorphous resin is controlled by the aromatic compound represented by the formula (I). Crystallization of the crystalline resin is easy to proceed, the storage stability is improved, and the aromatic compound represented by the formula (I) has a methoxy group having an electron donating property in the aromatic ring as compared with terephthalic acid or isophthalic acid. Since the hydroxyl groups are bonded to carbon atoms adjacent to each other, it becomes a monomer having a phenolic hydroxyl group with a high pKa (isoelectric point), and as a result of increasing the electron capacity in the aromatic ring, the rising property of charging is improved. Conceivable. If the number of methoxy groups bonded to the carbon atom adjacent to the carbon atom bonded to the hydroxyl group is at least one, the rising property of charging of the toner is improved, but two may be used.

  The aromatic compound represented by the formula (I) may be used as a carboxylic acid component and / or an alcohol component of an amorphous resin, and is used as a carboxylic acid component and / or an alcohol component of a crystalline resin. However, it is preferable that both resins are contained from the viewpoints of storage stability and charge build-up property. The carboxylic acid component is used when the aromatic compound represented by the formula (I) has a carboxyl group.

In X of the formula (I), the linking group that the hydroxyl group or carboxyl group may have is preferably a divalent hydrocarbon group having an unsaturated bond, and the number of carbon atoms is preferably 2 to 4, More preferably, a divalent hydrocarbon group of 2 or 3 is desirable, and when there is no linking group, X is a hydroxyl group or a carboxyl group. More specific examples of X include a group represented by —CH═CH—COOH or —CH═CH—CH ₂ OH.

As a preferred combination of R ¹ and X, when R ¹ is a hydrogen atom, X is an aldehyde group, an allyl group, a vinyl group, a methoxy group, or a hydroxyl group or a carboxyl group which may have a linking group. preferable. When R ¹ is a hydroxyl group, X is preferably a methoxy group or a hydroxyl group or a carboxyl group optionally having a linking group. Moreover, when R < ¹ > is a methoxy group, X is preferably a hydrogen atom, an aldehyde group, or a hydroxyl group or a carboxyl group which may have a linking group.

The molecular weight of the aromatic compound is preferably 1000 or less, more preferably 800 or less, from the viewpoint of condensation polymerization reactivity. The lower limit is 124 when both R ¹ and X are hydrogen atoms.

  The aromatic compound represented by the formula (I) acts as either a carboxylic acid component or an alcohol component during the condensation polymerization as a raw material monomer for polyester, depending on the type of functional group. Since hydroxycarboxylic acid is mainly polycondensed as a carboxylic acid component, in the present invention, for convenience, when X is a hydroxycarboxylic acid having a carboxyl group, X is a carboxylic acid component. When X is an alcohol having no carboxyl group, it is regarded as an alcohol component and used for calculation of the content and molar ratio. Generally, the reactivity of the hydroxyl group directly bonded to the aromatic ring is low, but the aromatic compound represented by the formula (I) has a methoxy group bonded to the carbon atom adjacent to the carbon atom to which the hydroxyl group is bonded. Since the reactivity is considered to be high, the alcohol component is used.

In the aromatic compound represented by the formula (I), as the aromatic compound used as the carboxylic acid component, ferulic acid (X: —CH═CH—COOH, R ¹ : hydrogen is used from the viewpoint of charge rising property of the toner. Atom), 5-hydroxyferulic acid (X: —CH═CH—COOH, R ¹ : hydroxyl group), sinapinic acid (X: —CH═CH—COOH, R ¹ : methoxy group), vanillic acid (X: —COOH) , R ¹ : H) and syringic acid (X: —COOH, R ¹ : methoxy group), preferably at least one hydroxycarboxylic acid selected from the group consisting of ferulic acid, 5-hydroxyferulic acid, sinapinic acid, And at least one hydroxycarboxylic acid selected from the group consisting of syringic acid.

Examples of the aromatic compound used as the alcohol component include vanillin (X: —CHO, R ¹ : hydrogen atom), eugenol (X: —CH ₂ —CH═CH ₂ , R ¹ : hydrogen atom), 2-methoxy. -4-vinylphenol (X: —CH═CH ₂ , R ¹ : hydrogen atom), 2,4-dimethoxyphenol (X: methoxy group, R ¹ : hydrogen atom), 2,6-dimethoxyphenol (X: hydrogen) Monoalcohol (phenolic hydroxyl group) such as atom, R ¹ : methoxy group; coniferyl alcohol (X: —CH═CH—CH ₂ OH, R ¹ : hydrogen atom), 5-hydroxyconiferyl alcohol (X: And diols (including phenolic hydroxyl groups) such as —CH═CH—CH ₂ OH, R ¹ : hydroxyl group, and sinapyal alcohol (X: —CH═CH—CH ₂ OH, R ¹ : methoxy group). Among these, toner charging In view of rising property, diols are preferred, coniferyl alcohol, at least one diol selected from the group consisting of 5-hydroxy coniferyl alcohol and sinapyl alcohol.

  In the present invention, both the amorphous resin and the crystalline resin are preferably polyester resins, but the amorphous resin is a composite containing a condensation polymerization resin and an addition polymerization resin, as will be described later. Resin may be used.

  The crystallinity of the resin is expressed as the ratio between the softening point and the maximum peak temperature of the endotherm measured by a differential scanning calorimeter, that is, the softening point / the maximum peak temperature of the endotherm. When the ratio is less than 0.6, the crystallinity is low and there are many amorphous portions. The crystallinity of the resin can be adjusted by the type and ratio of the raw material monomers, production conditions (for example, reaction temperature, reaction time, cooling rate) and the like. In the present invention, “crystalline resin” means a resin having a softening point / endothermic maximum peak temperature value of 0.6 to 1.4, preferably 0.8 to 1.2, more preferably 0.9 to 1.1. "Refers to a resin having a softening point / endothermic peak temperature value greater than 1.4 or less than 0.6, preferably greater than 1.4. The highest endothermic peak temperature refers to the temperature of the peak on the highest temperature side among the observed endothermic peaks. If the maximum peak temperature is within 20 ° C. from the softening point, the melting point is set, and the peak having a difference from the softening point exceeding 20 ° C. is a peak due to glass transition. In the present invention, the term “resin” means both a crystalline resin and an amorphous resin.

(Crystalline resin)
The aromatic monomer represented by the above formula (I) is contained in one of the carboxylic acid component and the alcohol component, which is a raw material monomer of the crystalline resin, to improve the storage stability and charge rising property of the toner. It is preferable from the viewpoint.

  The content of the aromatic compound represented by the formula (I) is the total amount of the carboxylic acid component and the alcohol component used for the production of the crystalline resin from the viewpoint of low-temperature fixability, storage stability, and charge rising property of the toner. , Preferably 0.5 to 40 mol%, more preferably 2.5 to 40 mol%, still more preferably 2.5 to 35 mol%, still more preferably 5 to 30 mol%, still more preferably 5 to 25 mol%, and more More preferably, it is 5-15 mol%.

  When the aromatic compound represented by the formula (I) is a hydroxycarboxylic acid, the content of the hydroxycarboxylic acid is used in the production of a crystalline resin from the viewpoint of low-temperature fixability, storage stability, and charge rising property of the toner. In the total amount of the carboxylic acid component to be provided, preferably 1 to 80 mol%, more preferably 5 to 80 mol%, still more preferably 10 to 70 mol%, still more preferably 10 to 50 mol%, still more preferably. 10 to 30 mol%.

  When the aromatic compound represented by the formula (I) is an alcohol having no carboxyl group, the content of the alcohol is a crystalline resin from the viewpoint of low-temperature fixability, storage stability, and charge rising property of the toner. In the total amount of the alcohol component used for the production of, preferably 1 to 80 mol%, more preferably 3 to 70 mol%, still more preferably 5 to 50 mol%, even more preferably 10 to 50 mol%, and more More preferably, it is 10-30 mol%.

  The carboxylic acid component and the alcohol component used for the crystalline resin may contain a carboxylic acid compound and / or alcohol other than the aromatic compound.

  The alcohol component used in the crystalline resin is preferably an aliphatic diol, preferably an α, ω-linear alkane diol, preferably an aliphatic diol having 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms. Is preferable from the viewpoint of low-temperature fixability and crystallinity of the toner.

  Aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 1,6-hexanediol, 1,4-butenediol, neopentyl glycol, 2,3-butanediol, 2,3-pentanediol, 2,4-pentanediol, 2,3-hexanediol, 3,4- Examples include hexanediol, 2,4-hexanediol, and 2,5-hexanediol.

  Among these, from the viewpoint of low-temperature fixability and crystallinity of the toner, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1, An α, ω-aliphatic diol having 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms such as 4-butenediol is preferable. From the viewpoint of storage stability of the toner, one kind of aliphatic alcohol (with the same carbon number and The content of (same structure) in the alcohol component is preferably 80 mol% or more, and more preferably 90 mol% or more.

  The content of the aliphatic diol is preferably 20 to 100 mol%, more preferably 30 to 100 mol%, still more preferably 50 to 100 mol% in the alcohol component of the crystalline resin from the viewpoint of low-temperature fixability of the toner. It is.

  When the aromatic compound is used as a carboxylic acid component (that is, when the aromatic compound represented by the formula (I) is a hydroxycarboxylic acid, the same applies hereinafter), the content of the aliphatic diol is From the viewpoint of low-temperature fixability, it is preferably 30 to 100 mol%, more preferably 50 to 100 mol%, and still more preferably 80 to 100 mol% in the alcohol component of the crystalline resin.

  When the aromatic compound is used as an alcohol component (that is, when the aromatic compound represented by the formula (I) is an alcohol having no carboxyl group, the same shall apply hereinafter), or the alcohol component and the carboxylic acid component When the aromatic compound is used for both (that is, when the aromatic compound represented by the formula (I) is used in combination with a hydroxycarboxylic acid and an alcohol having no carboxy group, the same shall apply hereinafter). The content of the diol is preferably 0 to 90 mol%, more preferably 20 to 90 mol% in the alcohol component of the crystalline resin from the viewpoint of low-temperature fixability of the toner.

  The alcohol component other than the aliphatic alcohol is represented by formula (II):

(Wherein R ² O and OR ² are oxyalkylene groups, R ² is an ethylene and / or propylene group, x and y indicate the number of moles of alkylene oxide added, each being a positive number, The average value of the sum of y and y is preferably 1 to 16, more preferably 1 to 8, and even more preferably 1.5 to 4)
An alkylene oxide adduct of bisphenol A represented by

  Specific examples of the alkylene oxide adduct of bisphenol A represented by the formula (II) include 2,2-bis (4-hydroxyphenyl) propane polyoxypropylene adduct and 2,2-bis (4-hydroxy). And an alkylene oxide adduct of bisphenol A such as a polyoxyethylene adduct of phenyl) propane.

  Other alcohols include trivalent or higher alcohols such as glycerin, pentaerythritol, and trimethylolpropane.

  The carboxylic acid component used for the crystalline resin is preferably an aromatic dicarboxylic acid compound or an aliphatic dicarboxylic acid compound. In the present invention, the term “carboxylic acid compound” is used generically, including derivatives such as carboxylic acids, acid anhydrides, and alkyl (C 1 -C 3) esters.

  As the aromatic dicarboxylic acid compound, phthalic acid, isophthalic acid, terephthalic acid and the like are preferable from the viewpoint of low-temperature fixability and storage stability of the toner.

  Aliphatic dicarboxylic acid compounds include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid. Examples thereof include aliphatic dicarboxylic acid compounds such as acids. Among these, aliphatic dicarboxylic acid compounds having 2 to 8 carbon atoms are preferred, and fumaric acid is more preferred from the viewpoint of low-temperature fixability and crystallinity of the toner. As described above, the aliphatic dicarboxylic compound refers to an aliphatic dicarboxylic acid, its anhydride, and its alkyl (C1-3) ester. Among these, an aliphatic dicarboxylic acid is preferable.

  In the carboxylic acid component, the content of the aromatic dicarboxylic acid compound and / or the aliphatic dicarboxylic acid compound is preferably 20 to 100 mol%, more preferably 30 to 90 mol, from the viewpoint of low-temperature fixability and storage stability of the toner. %, More preferably 40 to 80 mol%.

  When the aromatic compound represented by the formula (I) is used as the carboxylic acid component, or when the aromatic compound represented by the formula (I) is used for both the alcohol component and the carboxylic acid component, the aromatic dicarboxylic acid compound and The content of the aliphatic dicarboxylic acid compound is preferably 20 to 90 mol%, more preferably 30 to 90 mol% in the carboxylic acid component, from the viewpoint of low-temperature fixability and storage stability of the toner.

  When the aromatic compound represented by the formula (I) is used as an alcohol component, the content of the aromatic dicarboxylic acid compound and / or the aliphatic dicarboxylic acid compound is selected from the viewpoints of low-temperature fixability and storage stability of the toner. In a component, Preferably it is 20-100 mol%, More preferably, it is 30-90 mol%, More preferably, it is 40-90 mol%.

  Other carboxylic acid compounds such as cycloaliphatic dicarboxylic acid, cycloaliphatic dicarboxylic acids; trimellitic acid, pyromellitic acid and other polyvalent carboxylic acids; rosin; modified with fumaric acid, maleic acid, acrylic acid, etc. Rosin and the like.

  From the viewpoint of low-temperature fixability of the toner, the content of the trivalent or higher polyvalent carboxylic acid compound is preferably 15 mol% or less, more preferably 10 mol% or less, and even more preferably 3 mol% or less in the carboxylic acid component. .

(Amorphous resin)
From the viewpoint of the charge rising property of the toner, the aromatic monomer represented by the formula (I) is contained in either one of the carboxylic acid component and the alcohol component, which is a raw material monomer of the amorphous resin. preferable.

  The content of the aromatic compound represented by the formula (I) is preferably in the total amount of the carboxylic acid component and the alcohol component used for the production of the amorphous resin, from the viewpoint of storage stability and charge rising property of the toner. Is 0.5 to 80 mol%, more preferably 2.5 to 80 mol%, still more preferably 2.5 to 60 mol%, still more preferably 5 to 50 mol%, and still more preferably 5 to 25 mol%.

  When the aromatic compound represented by the formula (I) is a hydroxycarboxylic acid, the content of the hydroxycarboxylic acid is used for the production of an amorphous resin from the viewpoint of toner storage stability and charge build-up property. The total amount of the carboxylic acid component is preferably 10 to 100 mol%, more preferably 10 to 80 mol%, still more preferably 10 to 50 mol%.

  When the aromatic compound represented by the formula (I) is an alcohol that does not have a carboxyl group, the content of the alcohol is used in the production of an amorphous resin from the viewpoint of storage stability and charge rising property of the toner. It is preferably 10 to 100 mol%, more preferably 10 to 70 mol%, and still more preferably 10 to 50 mol%, in the total amount of the alcohol component to be provided.

  The carboxylic acid component and the alcohol component used for the amorphous resin may contain a carboxylic acid compound and / or an alcohol other than the aromatic compound.

  The alcohol component used in the amorphous resin is preferably an aliphatic diol, preferably an aliphatic diol having 2 to 8 carbon atoms, more preferably an aliphatic diol having 2 to 6 carbon atoms, from the viewpoint of low-temperature fixability of the toner. .

  Aliphatic diols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 1,6-hexanediol, 1,4-butenediol, neopentyl glycol, 2,3-butanediol, 2,3-pentanediol, 2,4-pentanediol, 2,3-hexanediol, 3,4- Examples include hexanediol, 2,4-hexanediol, and 2,5-hexanediol.

  Among these, an aliphatic diol having a hydroxyl group bonded to a secondary carbon atom is preferable from the viewpoint of excellent low-temperature fixability and storage stability of the toner. Such aliphatic diols preferably have 3 to 8 carbon atoms, more preferably 3 to 6 carbon atoms, from the viewpoint of low-temperature fixability and storage stability. Specific preferred examples include 1,2-propanediol, 1, Examples include 2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 2,3-pentanediol, and 2,4-pentanediol. .

  The content of the aliphatic diol is preferably 20 to 100 mol%, more preferably 30 to 100 mol%, still more preferably 50 to 100 mol in the alcohol component of the amorphous resin from the viewpoint of low-temperature fixability of the toner. %.

  When the aromatic compound represented by the formula (I) is used as the carboxylic acid component, the content of the aliphatic diol is preferably 30 to 30% in the alcohol component of the amorphous resin from the viewpoint of low-temperature fixability of the toner. It is 100 mol%, More preferably, it is 50-100 mol%, More preferably, it is 80-100 mol%.

  When the aromatic compound is used as an alcohol component, or when the aromatic compound is used as both an alcohol component and a carboxylic acid component, the content of the aliphatic diol is amorphous from the viewpoint of low-temperature fixability of the toner. In the alcohol component of the resin, it is preferably 0 to 90 mol%, more preferably 20 to 90 mol%, still more preferably 30 to 90 mol%.

  As the alcohol component other than the aliphatic alcohol, an alkylene oxide adduct of bisphenol A represented by the formula (II) is preferable from the viewpoint of storage stability of the toner.

  Specific examples of the alkylene oxide adduct of bisphenol A represented by the formula (II) include 2,2-bis (4-hydroxyphenyl) propane polyoxypropylene adduct and 2,2-bis (4-hydroxy). And an alkylene oxide adduct of bisphenol A such as a polyoxyethylene adduct of phenyl) propane.

  As the carboxylic acid component used in the amorphous resin, an aromatic dicarboxylic acid compound is preferable.

  Aromatic dicarboxylic acid compounds such as phthalic acid, isophthalic acid and terephthalic acid are preferred from the viewpoint of low-temperature fixability and storage stability of the toner.

  In the carboxylic acid component, the aromatic dicarboxylic acid compound is preferably 20 to 100 mol%, more preferably 30 to 90 mol%, and still more preferably 40 to 80 mol%, from the viewpoint of low-temperature fixability and storage stability of the toner. is there.

  When the aromatic compound represented by the formula (I) is used as the carboxylic acid component, or when the aromatic compound represented by the formula (I) is used for both the alcohol component and the carboxylic acid component, the aromatic dicarboxylic acid compound The content is preferably 20 to 90 mol%, more preferably 30 to 90 mol%, and still more preferably 30 to 80 mol% in the carboxylic acid component from the viewpoint of low-temperature fixability and storage stability of the toner.

  When the aromatic compound represented by the formula (I) is used as an alcohol component, the content of the aromatic dicarboxylic acid compound is preferably 20 to 100 in the carboxylic acid component from the viewpoint of low-temperature fixability and storage stability of the toner. It is mol%, More preferably, it is 30-90 mol%, More preferably, it is 40-80 mol%.

  Other carboxylic acids include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid Aliphatic dicarboxylic acids such as these, anhydrides of these acids, alkyl (1 to 3 carbon atoms) esters, and the like. Among these, dicarboxylic acid compounds having 2 to 8 carbon atoms are preferred, and fumaric acid compounds are more preferred. preferable. As described above, the aliphatic dicarboxylic compound refers to an aliphatic dicarboxylic acid, its anhydride, and its alkyl (C1-3) ester. Among these, an aliphatic dicarboxylic acid is preferable.

  Other carboxylic acid compounds such as cycloaliphatic dicarboxylic acid, cycloaliphatic dicarboxylic acids; trimellitic acid, pyromellitic acid and other polyvalent carboxylic acids; rosin; modified with fumaric acid, maleic acid, acrylic acid, etc. Rosin and the like.

  The content of the trivalent or higher polyvalent carboxylic acid compound is preferably 0 to 30 mol%, more preferably 3 to 20 mol% in the carboxylic acid component, from the viewpoint of low-temperature fixability of the toner.

  In both crystalline resins and amorphous resins, monohydric alcohol is used for the alcohol component, and monovalent carboxylic acid compound is used for the carboxylic acid component to improve the molecular weight of the resin and improve the offset resistance of the toner. From a viewpoint, you may contain suitably.

  In any of the amorphous resin and the crystalline resin, the molar ratio of the total number of moles of hydroxy groups and the total number of moles of carboxy groups contained in the alcohol component and the carboxylic acid component containing the aromatic compound (hydroxy The total number of moles of groups / the total number of moles of carboxy groups) is preferably 0.9 to 1.5, more preferably 1.0 to 1.5 from the viewpoint of improving the reactivity of the aromatic compound and improving the charge rising property of the toner. 1.4, more preferably 1.0 to 1.3.

  In both the amorphous resin and the crystalline resin, the condensation polymerization reaction between the alcohol component and the carboxylic acid component is carried out, for example, in the presence of an esterification catalyst such as a tin compound or a titanium compound, a polymerization inhibitor, or the like. It can be performed in an atmosphere, and the temperature condition is usually preferably about 150 to 250 ° C., but from the viewpoint of improving the reactivity of the aromatic compound, improving the charge rising property and improving the decomposition stability, After the aromatic compound is added, the reaction is preferably performed at 150 to 200 ° C, more preferably 160 to 200 ° C. Further preferred embodiments include an aromatic dicarboxylic acid compound and an aliphatic dicarboxylic acid compound other than the aromatic compound from the viewpoint of improving the reactivity of the aromatic compound, improving the charge rising property and improving the decomposition stability. After subjecting the carboxylic acid component such as aliphatic diol and aromatic diol to a polycondensation reaction preferably at 200 to 250 ° C., more preferably 210 to 240 ° C., the aromatic compound is added. , Preferably 150 to 200 ° C, more preferably 160 to 200 ° C. When the aromatic compound is added, the reaction rate between the carboxylic acid component and the alcohol component is preferably 50 to 100%, more preferably 60 to 90% in terms of a calculated value from the theoretical reaction water amount.

  As the tin compound, for example, dibutyltin oxide is known. However, in the present invention, tin (II) having no Sn—C bond is used from the viewpoint of good dispersibility in the condensation polymerization resin. Compounds are preferred.

  Examples of the tin (II) compound having no Sn—C bond include a tin (II) compound having a Sn—O bond, a tin (II) compound having a Sn—X (X represents a halogen atom) bond, and the like. Preferably, a tin (II) compound having a Sn—O bond is more preferable.

Examples of tin (II) compounds having Sn-O bonds include tin (II) oxalate, tin (II) acetate, tin (II) octoate, tin (II) 2-ethylhexanoate, and tin (II) laurate. , Tin (II) carboxylate having a carboxylic acid group having 2 to 28 carbon atoms such as tin (II) stearate, tin (II) oleate; octyloxy tin (II), lauroxy tin (II), stearoxy tin (II) ), Alkoxytin (II) having an alkoxy group having 2 to 28 carbon atoms such as oleyloxytin (II); tin (II) oxide; tin (II) sulfate, Sn—X (X represents a halogen atom) Examples of the tin (II) compound having a bond include tin (II) halides such as tin (II) chloride and tin (II) bromide. Among these, from the viewpoint of catalytic ability, (R ³ COO) ₂ Sn (wherein R ³ represents an alkyl or alkenyl group having 5 to 19 carbon atoms) fatty acid tin (II), (R ⁴ O) ₂ Sn (where R ⁴ is carbon 6 ~ 20 alkyl or alkenyl groups Alkoxy tin (II) and tin oxide represented by SnO (II) is preferably represented by the be), (R ³ COO) is more preferably a fatty acid tin represented by ₂ Sn (II) and tin oxide (II) Further preferred are tin (II) octoate, tin (II) 2-ethylhexanoate, tin (II) stearate and tin (II) oxide.

  As the titanium compound, a titanium compound having a Ti-O bond is preferable, and a compound having an alkoxy group having 1 to 28 carbon atoms, an alkenyloxy group having 2 to 28 carbon atoms, or an acyloxy group having 1 to 28 carbon atoms in total is preferable. More preferred.

Specific examples of titanium compounds include titanium diisopropylate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₃ H ₇ O) ₂ ], titanium diisopropylate bisdiethanolamate [Ti (C ₄ H ₁₀ O ₂ N) ₂ (C ₃ H ₇ O) ₂ ], titanium dipentylate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₅ H ₁₁ O) ₂ ], titanium diety rate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (C 2 H 5 O) 2 ], titanium dihydroxy octylate bis triethanolaminate _{[Ti (C 6 H 14 O 3} N) 2 (OHC 8 H ₁₆ O) ₂ ], titanium distearate bistriethanolamate [Ti (C ₆ H ₁₄ O ₃ N) ₂ (C ₁₈ H ₃₇ O) ₂ ], titanium triisopropylate triethanolamate [Ti (C ₆ H ₁₄ O ₃ N) (C ₃ H ₇ O) ₃ ], titanium monopropylate tris (triethanolaminate) [Ti (C ₆ H ₁₄ O ₃ N) ₃ (C ₃ H ₇ O)] and the like, among these, titanium diisopropylate bistri Ethanolaminate, titanium diisopropylate bisdiethanolamate and titanium dipentylate bistriethanolamate are preferred, and these are also available as commercial products of Matsumoto Trading Co., Ltd., for example.

Specific examples of other preferable titanium compounds include tetra-n-butyl titanate [Ti (C ₄ H ₉ O) ₄ ], tetrapropyl titanate [Ti (C ₃ H ₇ O) ₄ ], tetrastearyl titanate [Ti ( C ₁₈ H ₃₇ O) ₄ ], tetramyristyl titanate [Ti (C ₁₄ H ₂₉ O) ₄ ], tetraoctyl titanate [Ti (C ₈ H ₁₇ O) ₄ ], dioctyl dihydroxyoctyl titanate [Ti (C ₈ H ₁₇ O) ₂ (OHC ₈ H ₁₆ O) ₂ ], dimyristyl dioctyl titanate [Ti (C ₁₄ H ₂₉ O) ₂ (C ₈ H ₁₇ O) ₂ ] and the like. Among these, tetrastearyl titanate, tetra Myristyl titanate, tetraoctyl titanate and dioctyl dihydroxy octyl titanate are preferred. These can be obtained, for example, by reacting a titanium halide with a corresponding alcohol, or can be obtained as a commercial product such as Nisso.

  The said tin (II) compound and titanium compound can be used 1 type or in combination of 2 or more types.

  The amount of the esterification catalyst is preferably 0.01 to 2.0 parts by weight, more preferably 0.1 to 1.5 parts by weight, and still more preferably 0.2 to 1.0 parts by weight with respect to 100 parts by weight of the total amount of the alcohol component and the carboxylic acid component.

  In the present invention, it is possible to use a pyrogallol compound having a benzene ring in which hydrogen atoms bonded to three carbon atoms adjacent to each other are substituted with a hydroxyl group as an auxiliary catalyst together with an esterification catalyst. This is preferable from the viewpoint of increasing the reactivity and improving the storage stability of the toner.

  Examples of pyrogallol compounds include pyrogallol, gallic acid, gallic acid esters, 2,3,4-trihydroxybenzophenone, benzophenone derivatives such as 2,2 ', 3,4-tetrahydroxybenzophenone, epigallocatechin, epigallocatechin gallate, etc. Among these, from the viewpoint of the durability of the resulting resin, the formula (III):

Wherein R ^{5 to} R ⁷ are each independently a hydrogen atom or —COOR ⁸ (R ⁸ is a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, preferably an alkyl group or carbon having 1 to 12 carbon atoms. Represents an alkenyl group of 2 to 12)
The compound represented by these is preferable. In the formula, the hydrocarbon group of R ⁸ preferably has 1 to 8 carbon atoms, and more preferably 1 to 4 carbon atoms from the viewpoint of reaction activity. Among the compounds represented by the formula (III), a compound in which R ⁵ and R ⁷ are hydrogen atoms and R ⁶ is a hydrogen atom or —COOR ⁸ is more preferable. Specific examples include pyrogallol (R ^{5 to} R ⁷ : hydrogen atom), gallic acid (R ⁵ and R ⁷ : hydrogen atom, R ⁶ : —COOH), ethyl gallate (R ⁵ and R ⁷ : hydrogen atom, R ^6: -COOC ₂ H _5), propyl gallate (R ⁵ and R ^7: a hydrogen _{^{atom, R 6: -COOC 3 H 7}} ), butyl gallate (R ⁵ and R ^7: a hydrogen atom, R ^6: -COOC ₄ H _9), octyl gallate (R ⁵ and R ^7: a hydrogen _{^{atom, R 6: -COOC 8 H 17}} ), lauryl gallate (R ⁵ and R ^7: a hydrogen _{^{atom, R 6: -COOC 12 H 25}} ) And gallic acid esters. From the viewpoint of toner storage stability, gallic acid and gallic acid esters are preferred.

  The amount of the pyrogallol compound in the condensation polymerization reaction is 0.001 to 1.0 part by weight from the viewpoint of storage stability of the toner with respect to 100 parts by weight of the total of the reactant, alcohol component and carboxylic acid component subjected to the condensation polymerization reaction. Is preferable, 0.005-0.4 weight part is more preferable, 0.01-0.2 weight part is further more preferable. Here, the abundance of the pyrogallol compound means the total amount of the pyrogallol compound subjected to the condensation polymerization reaction.

  The pyrogallol compound is considered to function as a promoter for the esterification catalyst. The esterification catalyst used together with the pyrogallol compound is preferably at least one metal catalyst selected from the group consisting of tin compounds, titanium compounds, antimony trioxide, zinc acetate, and germanium dioxide.

  The weight ratio of the pyrogallol compound to the esterification catalyst (pyrogallol compound / esterification catalyst) is preferably from 0.01 to 0.5, more preferably from 0.03 to 0.3, and even more preferably from 0.05 to 0.2, from the viewpoint of storage stability of the toner.

  Examples of the condensation polymerization resin include polyester and polyester / polyamide from the viewpoint of low-temperature fixability of the toner. From the viewpoint of toner durability and charge stability, polyester is preferable.

  In addition, polyester modified | denatured to such an extent that the characteristic is not impaired substantially may be sufficient. Examples of the modified polyester include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, and the like. Polyester.

  The amorphous resin may be a composite resin containing a condensation polymerization resin and an addition polymerization resin such as a vinyl resin. The composite resin may be a mixture of a condensation polymerization resin and an addition polymerization resin. For example, a raw material monomer of a condensation polymerization resin and a raw material monomer of an addition polymerization resin are polymerized in the same reaction vessel. Can also be obtained.

  As the composite resin, by using a bireactive monomer capable of reacting with both the raw material monomer of the condensation polymerization resin and the raw material monomer of the addition polymerization resin, the addition polymerization resin component is finer in the condensation polymerization resin component. Furthermore, a hybrid resin that is uniformly dispersed is preferable. Both reactive monomers have at least one functional group selected from the group consisting of a hydroxyl group, a carboxyl group, an epoxy group, a primary amino group and a secondary amino group in the molecule, preferably a hydroxyl group and / or carboxyl. Group, more preferably a compound having a carboxyl group and an ethylenically unsaturated bond, and acrylic acid, methacrylic acid, fumaric acid and the like are preferable.

  In the present invention, the amount of the both reactive monomers is included in the total amount of the alcohol component and the carboxylic acid component as a raw material monomer for the condensation polymerization resin.

  The softening point of the amorphous resin is preferably 90 to 160 ° C., more preferably 95 to 155 ° C., and further preferably 115 to 150 ° C. from the viewpoint of low-temperature fixability and storage stability of the toner. The glass transition point is preferably 45 to 85 ° C., more preferably 50 to 80 ° C., and still more preferably 58 to 75 ° C. from the viewpoint of low-temperature fixability and storage stability of the toner. The glass transition point is a physical property peculiar to an amorphous resin, and is distinguished from the maximum peak temperature of endotherm.

  The acid value of the amorphous resin is preferably from 1 to 90 mgKOH / g, more preferably from 5 to 90 mgKOH / g, and even more preferably from 5 to 88 mgKOH / g, from the viewpoints of chargeability and environmental stability of the toner. The hydroxyl value is preferably 5 to 90 mgKOH / g, more preferably 5 to 70 mgKOH / g, from the viewpoints of chargeability and environmental stability.

  On the other hand, the melting point of the crystalline resin is preferably 70 to 140 ° C., more preferably 80 to 120 ° C., and still more preferably 90 to 115 ° C. from the viewpoint of low-temperature fixability of the toner. The melting point of the crystalline resin can be determined as the maximum peak temperature of the endothermic resin described later.

  The softening point of the crystalline resin is preferably 60 to 130 ° C, more preferably 70 to 125 ° C, and still more preferably 85 to 120 ° C, from the viewpoint of low-temperature fixability of the toner. The melting point and softening point of the crystalline resin can be easily adjusted by adjusting the raw material monomer composition, the polymerization initiator, the molecular weight, the catalyst amount, etc., or selecting the reaction conditions.

  In the binder resin of the present invention, the weight ratio of the crystalline resin to the amorphous resin (crystalline resin / amorphous resin) is preferably 10/90 to 50/50, preferably 10/90 to 40/60. More preferably, 10/90 to 30/70 is more preferable, and 20/80 to 30/70 is still more preferable.

  By using the binder resin of the present invention, it is possible to obtain the electrophotographic toner of the present invention which is excellent in charge rising property while satisfying low-temperature fixability and storability which are mutually contradictory performances.

  In the toner of the present invention, a known binder resin other than the binder resin of the present invention, for example, a vinyl resin such as polyester, styrene-acrylic resin, an epoxy resin, a polycarbonate, A resin such as polyurethane may be used in combination, but the content of the binder resin of the present invention is preferably 30% by weight or more, more preferably 50% by weight or more, and 70% by weight or more in the total binder resin. More preferably, 80% by weight or more is more preferable, 90% by weight or more is further preferable, and substantially 100% by weight is further preferable.

  The toner of the present invention further includes a colorant, a release agent, a charge control agent, a magnetic powder, a fluidity improver, a conductivity modifier, an extender pigment, a reinforcing filler such as a fibrous substance, an antioxidant, and an aging agent. Additives such as an inhibitor and a cleaning property improver may be appropriately contained.

  As the colorant, all of dyes and pigments used as toner colorants can be used. Carbon black, black pigment, phthalocyanine blue, permanent brown FG, brilliant first scarlet, pigment green B, rhodamine- B base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, Quinacridone, Carmine 6B, Isoindoline, Disazo yellow and the like can be used alone or in combination of two or more. The toner may be either black toner or color toner.

  The content of the colorant is preferably 1 to 40 parts by weight and more preferably 2 to 10 parts by weight with respect to 100 parts by weight of the binder resin.

  The charge control agent is not particularly limited, and may contain either a positively chargeable charge control agent or a negatively chargeable charge control agent.

  Examples of positively chargeable charge control agents include nigrosine dyes such as “Nigrosine Base EX”, “Oil Black BS”, “Oil Black SO”, “Bontron N-01”, “Bontron N-07”, “Bontron N-09” ”,“ Bontron N-11 ”(manufactured by Orient Chemical Co., Ltd.), etc .; triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salt compounds such as“ Bontron P-51 ”(Orient Chemical) Manufactured by Kogyo Co., Ltd.), cetyltrimethylammonium bromide, “COPY CHARGE PX VP435” (manufactured by Hoechst), etc .; polyamine resin such as “AFP-B” (manufactured by Orient Chemical Co., Ltd.), etc .; imidazole derivatives such as “PLZ-2001” , “PLZ-8001” (manufactured by Shikoku Kasei Co., Ltd.) and the like.

  In addition, as a negatively chargeable charge control agent, metal-containing azo dyes such as “Varifirst Black 3804”, “Bontron S-31” (above, manufactured by Orient Chemical Industries), “T-77” (Hodogaya Chemical) Manufactured by Kogyo Co., Ltd.), Bontron S-32, Bontron S-34, Bontron S-36 (above, Orient Chemical Co., Ltd.), Eisenspiron Black TRH (Hodogaya Chemical Co., Ltd.) A metal compound of a benzylic acid compound, such as “LR-147”, “LR-297” (manufactured by Nippon Carlit Co., Ltd.); a metal compound of a salicylic acid compound, such as “Bontron E-81”, “Bontron E- 84, “Bontron E-88”, “E-304” (manufactured by Orient Chemical Co., Ltd.), “TN-105” (manufactured by Hodogaya Chemical Co., Ltd.); copper phthalocyanine dye; quaternary ammonium salt such as “ COPY CHARGE NX VP434 "(Hoechst), nitroimidazole derivative; organometallic compound , For example, "TN105" (commercially available from Hodogaya Chemical Co., Ltd.), and the like.

  The content of the charge control agent is preferably 0.01 to 10 parts by weight, more preferably 0.01 to 5 parts by weight, and more preferably 0.3 to 3 parts by weight with respect to 100 parts by weight of the binder resin, from the viewpoint of the charge rising property of the toner. More preferably, 0.5 to 3 parts by weight is even more preferable, and 1 to 2 parts by weight is even more preferable.

  The present invention preferably contains a charge control resin in order to improve chargeability. As the charge control resin, a styrene resin is preferable, and from the viewpoint of developing positive chargeability of the toner, a quaternary ammonium base-containing styrene resin is preferable, and from the viewpoint of developing negative chargeability of the toner, a sulfonic acid group-containing styrene. Based resins are preferred.

  As the quaternary ammonium base-containing styrene resin, the formula (IVa):

(Wherein R ⁹ represents a hydrogen atom or a methyl group)
A monomer represented by the formula (IVb):

(Wherein R ¹⁰ represents a hydrogen atom or a methyl group, and R ¹¹ represents an alkyl group having 1 to 12 carbon atoms)
And a monomer represented by formula (IVc):

(Wherein R ¹² represents a hydrogen atom or a methyl group, and R ¹³ and R ¹⁴ each independently represents an alkyl group having 1 to 4 carbon atoms)
A quaternary ammonium base-containing styrene acrylic resin obtained by polymerizing a monomer mixture containing the monomer represented by the formula (1) or a quaternized product thereof is more preferable. The monomer may be quaternized in advance, or may be quaternized after polymerization. Examples of the quaternizing agent include alkyl halides such as methyl chloride and methyl iodide, diethyl sulfate, and di-n-propyl sulfate.

As the monomer represented by the formula (IVa), styrene in which R ⁹ is preferably a hydrogen atom is preferable, and as the monomer represented by the formula (IVb), R ¹⁰ is preferably a hydrogen atom, and R ¹¹ is preferably an alkyl group having 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms. Specific examples of the monomer represented by the formula (IVb) include butyl acrylate and 2-ethylhexyl acrylate. The monomer represented by the formula (IVc) is preferably a monomer in which R ¹² is a methyl group, and R ¹³ and R ¹⁴ are a methyl group or an ethyl group, and more preferably R ¹² , R ¹³ and R ^14. Each is preferably dimethylaminoethyl methacrylate where is a methyl group.

  In the quaternary ammonium base-containing styrene resin, the content of the monomer represented by the formula (IVa) in the monomer mixture is preferably 60 to 97% by weight, more preferably 70 to 90% by weight. The content of the monomer represented by the formula (IVb) is preferably 1 to 33% by weight, more preferably 5 to 20% by weight, and the monomer represented by the formula (IVc) or 4 thereof The content of the graded product is preferably 2 to 35% by weight, more preferably 5 to 20% by weight.

  Specific examples of the quaternary ammonium base-containing styrenic resin obtained using the monomers represented by the formulas (IVa) to (IVc) include butyl acrylate, N, N-diethyl-N-methyl-2- And (methacryloyloxy) ethylammonium / styrene copolymer.

  As the sulfonic acid group-containing styrene resin, the monomer represented by the above formula (IVa), the monomer represented by the formula (IVb), and the monomer containing the sulfonic acid group-containing monomer A sulfonic acid group-containing styrene resin obtained by polymerizing the mixture is preferred.

  Examples of the sulfonic acid group-containing monomer include (meth) allylsulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, and styrenesulfonic acid. Specific examples include 2-ethylhexyl acrylate, 2-acrylamido-2-methyl-1-propanesulfonic acid, styrene copolymer, and the like.

  In the sulfonic acid group-containing styrenic resin, the content of the monomer represented by the formula (IVa) in the monomer mixture is preferably 60 to 97 wt%, more preferably 70 to 90 wt%, The content of the monomer represented by the formula (IVb) is preferably 1 to 33% by weight, more preferably 5 to 20% by weight, and the content of the sulfonic acid group-containing monomer is preferably 2 to 35%. It is desirable that the amount be 5% by weight, more preferably 5 to 20% by weight.

  In both the quaternary ammonium group-containing styrene resin and the sulfonic acid group-containing styrene resin, the polymerization of the monomer mixture is performed, for example, in the presence of a polymerization initiator such as azobisdimethylvaleronitrile. It can carry out by heating to 50-100 degreeC in inert gas atmosphere. The polymerization method may be any of solution polymerization, suspension polymerization or bulk polymerization, but is preferably solution polymerization.

  The softening point of the styrenic resin is preferably from 100 to 140 ° C, more preferably from 110 to 130 ° C, from the viewpoint of low-temperature fixability of the toner.

  The amount of the styrenic resin contained as the charge control resin is preferably 3 to 40 parts by weight, more preferably 4 to 30 parts by weight with respect to 100 parts by weight of the binder resin, from the viewpoint of developing the chargeability of the toner. 5 to 20 parts by weight is more preferable.

  Release agents include polyolefin wax, paraffin wax, silicones; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, stearic acid amide; carnauba wax, rice wax, candelilla wax, wood wax, jojoba Plant waxes such as oils; animal waxes such as beeswax; waxes such as mineral and petroleum waxes such as montan wax, ozokerite, ceresin, microcrystalline wax, and Fischer-Tropsch wax, which are used alone or in combination of two or more Can be mixed and used.

  The melting point of the release agent is preferably 60 to 160 ° C., more preferably 60 to 150 ° C., from the viewpoints of low-temperature fixability and offset resistance of the toner.

  The content of the release agent is preferably 0.5 to 10 parts by weight, more preferably 1 to 8 parts by weight, and more preferably 1.5 to 7 parts by weight from the viewpoint of dispersibility in the binder resin with respect to 100 parts by weight of the binder resin. Part by weight is more preferred.

  The toner of the present invention may be a toner obtained by any conventionally known method such as a melt-kneading method, an emulsion phase inversion method, or a polymerization method, but from the viewpoint of productivity and dispersibility of the colorant, A pulverized toner obtained by a melt kneading method is preferred. In the case of pulverized toner by the melt-kneading method, for example, after a raw material such as a binder resin, a colorant, a charge control agent, and a release agent is uniformly mixed with a mixer such as a Henschel mixer, a sealed kneader, uniaxial or 2 It can be manufactured by melt-kneading with a shaft extruder, open roll type kneader or the like, cooling, pulverizing and classifying. On the other hand, from the viewpoint of reducing the particle size of the toner, a toner by a polymerization method is preferable.

The volume median particle size (D ₅₀ ) of the toner of the present invention is preferably 3 to 15 μm, more preferably 3 to 10 μm. In the present specification, the volume-median particle size (D ₅₀ ) means a particle size at which the cumulative volume frequency calculated by the volume fraction is 50% when calculated from the smaller particle size.

  In the toner of the present invention, it is preferable to use inorganic fine particles as an external additive in order to improve transferability. Specifically, at least one selected from the group consisting of silica, alumina, titania, zirconia, tin oxide, and zinc oxide is preferable. Among these, silica is preferable, and from the viewpoint of preventing embedding, the specific gravity is More preferably, small silica is contained.

  Silica is preferably hydrophobic silica that has been subjected to a hydrophobic treatment, from the viewpoint of toner transferability.

  As a method for hydrophobizing silica, silanol groups on the surface of silica particles are preferably modified with a hydrophobic group such as an alkylsilyl group having 1 to 12 carbon atoms (for example, methylsilyl group, hexylsilyl group, etc.), or It is preferable to coat the surface with a hydrophobic resin.

  Examples of the hydrophobizing agent for hydrophobizing the surface of silica particles include organochlorosilane, organoalkoxysilane, organodisilazane, cyclic organopolysilazane, linear organopolysiloxane, and the like. Examples include silazane, dimethyldichlorosilane (DMDS), silicone oil, octyltriethoxysilane, methyltriethoxysilane, and the like. Among these, dimethyldichlorosilane is preferable.

  The average particle diameter of the external additive is from 10 to 250 nm, preferably from 10 to 200 nm, more preferably from 15 to 90 nm, from the viewpoint of chargeability, fluidity, and transferability of the toner.

  The content of the external additive is preferably 0.05 to 5 parts by weight, more preferably 0.1 to 3 parts by weight, and still more preferably 0.3 to 100 parts by weight of toner particles before being processed with the external additive. ~ 3 parts by weight.

  The toner of the present invention can be used as a one-component developing toner or as a two-component developer mixed with a carrier.

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

[Glass transition point of resin]
Using a differential scanning calorimeter (Seiko Denshi Kogyo Co., Ltd., DSC210), weigh 0.01 to 0.02 g of the sample into an aluminum pan, raise the temperature to 200 ° C, and from that temperature to 0 ° C at a rate of 10 ° C / min. The temperature of the cooled sample is raised at a heating rate of 10 ° C / min, and the temperature at the intersection of the base line extension below the maximum peak temperature of endotherm and the tangent that indicates the maximum slope from the peak rise to the peak apex To do.

[Maximum peak temperature of resin endotherm]
Using a differential scanning calorimeter (DSC Q20, manufactured by TA Instruments Japan), the sample was heated to 200 ° C and cooled to 0 ° C at a temperature decrease rate of 10 ° C / min. Increase the temperature at 10 ° C / min to obtain the maximum endothermic peak temperature.

[Acid value of the resin]
Measured according to the method of JIS K0070. However, only the measurement solvent was changed from the mixed solvent of ethanol and ether specified in JIS K0070 to the mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Hydroxyl value of the resin]
Measured according to the method of JIS K0070.

[Melting point of release agent]
Using a differential scanning calorimeter (Seiko Denshi Kogyo Co., Ltd., DSC210), the temperature was raised to 200 ° C, and the sample was cooled to 0 ° C at a temperature drop rate of 10 ° C / min. The maximum peak temperature of heat of fusion is taken as the melting point.

[Average particle size of external additives]
The average particle diameter refers to the number average particle diameter, which is the average value of the particle diameters of 500 particles measured from a scanning electron microscope (SEM) photograph of the external additive. When there is a major axis and a minor axis, the major axis is indicated.

[Volume-median particle diameter of toner (D ₅₀ )]
Measuring machine: Coulter Multisizer II (Beckman Coulter, Inc.)
Aperture diameter: 50μm
Analysis software: Coulter Multisizer AccuComp version 1.19 (Beckman Coulter)
Electrolyte: Isoton II (Beckman Coulter, Inc.)
Dispersion: Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB: 13.6) 5% electrolyte dispersion condition: 10 mg of measurement sample is added to 5 ml of dispersion, and dispersed for 1 minute with an ultrasonic disperser. Then, 25 ml of the electrolytic solution is added, and further dispersed with an ultrasonic disperser for 1 minute.
Measurement conditions: Add 100 ml of electrolyte and dispersion in a beaker, measure 30,000 particles at a concentration that can measure the particle size of 30,000 particles in 20 seconds, and determine the volume-median particle size ( determine the D _50).

Amorphous polyester production example 1 [resins A1, A3, A6]
A dehydration tube equipped with a nitrogen introduction tube and a fractionation tube through which hot water of 100 ° C. is passed through the raw material monomer and esterification catalyst other than the trimellitic anhydride shown in Table 1 and the aromatic compound represented by the formula (I) Into a 5 liter four-necked flask equipped with a stirrer and a thermocouple, kept at 180 ° C. for 1 hour in a nitrogen atmosphere and then heated from 180 ° C. to 230 ° C. at 10 ° C./hr, then 230 ° C. For 10 hours (reaction rate 70 to 80% based on the theoretical water content). Furthermore, after adding the aromatic compound shown in Table 1 and reacting at 180 ° C. for 5 hours, adding trimellitic anhydride shown in Table 1 and reacting at 200 ° C., the desired softening point at 10 kPa The reaction was carried out until an amorphous polyester was obtained.

Production Example 2 of Amorphous Polyester [Resin A2]
Raw material monomers and esterification catalysts other than trimellitic anhydride shown in Table 1 are 5 liters equipped with a nitrogen introducing tube, a dehydrating tube equipped with a fractionating tube through hot water at 100 ° C, a stirrer and a thermocouple. Was kept at 180 ° C. for 1 hour in a nitrogen atmosphere, and then the temperature was raised from 180 ° C. to 230 ° C. at 10 ° C./hr, followed by a condensation polymerization reaction at 230 ° C. for 10 hours. Furthermore, trimellitic anhydride shown in Table 1 was added, reacted at 200 ° C., and reacted at 10 kPa until a desired softening point was reached, thereby obtaining an amorphous polyester.

Production Example 3 of Amorphous Polyester [Resin A4]
Raw material monomers and esterification catalysts other than trimellitic anhydride shown in Table 1 and the aromatic compound represented by formula (I) are mixed in a 5-liter capacity equipped with a dehydration tube equipped with a nitrogen introduction tube, a stirrer and a thermocouple. Were subjected to a condensation polymerization reaction at 230 ° C. for 10 hours under a nitrogen atmosphere, and further reacted at 230 ° C. and 8.0 kPa for 1 hour (reaction rate 70 to 80% based on the theoretical reaction water amount). Furthermore, after adding the aromatic compound shown in Table 1 and reacting at 180 ° C. for 5 hours, adding trimellitic anhydride shown in Table 1 and reacting at 200 ° C., the desired softening point at 10 kPa The reaction was carried out until an amorphous polyester was obtained.

Production Example 4 of Amorphous Polyester [Resin A5]
Raw material monomers other than trimellitic anhydride shown in Table 1 and the esterification catalyst were put into a 5-liter four-necked flask equipped with a dehydration tube equipped with a nitrogen introduction tube, a stirrer and a thermocouple, and in a nitrogen atmosphere, The polycondensation reaction was carried out at 230 ° C. for 10 hours, and the reaction was further carried out at 230 ° C. and 8.0 kPa for 1 hour. Furthermore, trimellitic anhydride shown in Table 1 was added, reacted at 200 ° C., and reacted at 10 kPa until a desired softening point was reached, thereby obtaining an amorphous polyester.

Production Example 1 of Hybrid Resin [Resin H1]
Polyester raw material monomers and esterification catalysts other than trimellitic anhydride shown in Table 2 were equipped with a nitrogen introduction tube, a dehydration tube equipped with a fractionating tube through which 100 ° C hot water was passed, a stirrer and a thermocouple. The flask was placed in a four-liter flask and heated to 160 ° C. in a nitrogen atmosphere. Thereafter, a mixture of the both reactive monomers shown in Table 2, the raw material monomer of the styrene resin, and the polymerization initiator was added dropwise over 1 hour with a dropping funnel. After the dropwise addition, the addition polymerization reaction was aged for 1 hour while maintaining the temperature at 160 ° C., followed by condensation polymerization reaction at 230 ° C. for 10 hours, and further reaction at 230 ° C. and 8.0 kPa for 1 hour. Furthermore, trimellitic anhydride shown in Table 2 was added, and a reaction was performed at 200 ° C. and 10 kPa until a desired softening point was reached, thereby obtaining a hybrid resin.

Production Example 2 of Hybrid Resin [Resin H2]
Put polyester raw material monomer and esterification catalyst other than trimellitic anhydride shown in Table 2 into a 5-liter four-necked flask equipped with a dehydration tube equipped with a nitrogen introduction tube, a stirrer and a thermocouple, and a nitrogen atmosphere. The temperature was raised to 160 ° C. Thereafter, a mixture of the both reactive monomers shown in Table 2, the raw material monomer of the styrene resin, and the polymerization initiator was added dropwise over 1 hour using a dropping funnel. After the dropwise addition, the addition polymerization reaction was aged for 1 hour while maintaining the temperature at 160 ° C., followed by condensation polymerization reaction at 230 ° C. for 10 hours, and further reaction at 230 ° C. and 8.0 kPa for 1 hour. Furthermore, trimellitic anhydride shown in Table 2 was added, reacted at 200 ° C., and reacted at 10 kPa until a desired softening point was reached, thereby obtaining a hybrid resin.

Production Example 1 of Crystalline Polyester [Resin C1, C3-C6, C8-C13]
The raw material monomers and the esterification catalyst shown in Tables 3 to 5 were placed in a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, and reacted at 160 ° C. for 5 hours. Thereafter, the temperature was raised to 200 ° C. and reacted to obtain a crystalline polyester.

Production Example 2 of Crystalline Polyester [Resin C2]
Raw material monomers and esterification catalyst other than trimellitic anhydride shown in Table 3 were placed in a 5-liter four-necked flask equipped with a nitrogen introduction tube, dehydration tube, stirrer, and thermocouple, and were heated at 160 ° C for 5 hours. Then, the temperature was raised to 200 ° C. Furthermore, trimellitic anhydride shown in Table 3 was added and reacted for 20 minutes to obtain a crystalline polyester.

Production Example 3 of Crystalline Polyester [Resin C7]
The raw material monomer and esterification catalyst shown in Table 4 were put into a 5-liter four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and reacted at 180 ° C. for 5 hours. The temperature was raised to 200 ° C. and reacted to obtain a crystalline polyester.

Examples 1-12, 16-21, 25 and Comparative Examples 1-4
100 parts by weight of binder resin shown in Table 6, 1 part by weight of negative charge control agent “Bontron S-34” (manufactured by Orient Chemical Co., Ltd., azo metal compound), colorant “Regal 330R” (manufactured by Cabot, carbon Black) 4.0 parts by weight and polypropylene wax “NP-105” (manufactured by Mitsui Chemicals, melting point: 140 ° C.) 2.0 parts by weight were mixed using a Henschel mixer. The obtained mixture was melt-kneaded by a twin screw extruder, cooled, and then roughly pulverized to about 1 mm using a hammer mill. The resulting coarsely pulverized product is finely pulverized by an air jet type pulverizer (IDS-2 type, manufactured by Nippon Pneumatic Co., Ltd.), classified, and toner particles having a volume median particle size (D ₅₀ ) of 7.5 μm. Got.

  To 100 parts by weight of the obtained toner particles, 1.0 part by weight of hydrophobic silica “Aerosil R-972” (manufactured by Nippon Aerosil Co., Ltd., average particle diameter of 16 nm, hydrophobizing agent: dimethyldichlorosilane) is added as an external additive. The toner was obtained by mixing with a Henschel mixer.

Examples 13-15
As a colorant, instead of carbon black “Regal 330R”, in Example 13, 6 parts by weight of yellow pigment “Paliotol Yellow D1155” (manufactured by BASF, PY185), in Example 14, the magenta pigment “Super Magenta R” ( Dainippon Ink & Chemicals, PR122) 6 parts by weight, Example 15 uses the same pigment as Example 1 except that 6 parts by weight of the cyan pigment “Toner Cyan BG” (Clariant, PB15: 3) is used. The toner was obtained.

Example 22
Except for using 7 parts by weight of charge control resin `` FCA-701PT '' (manufactured by Fujikura Kasei Co., Ltd., quaternary ammonium base-containing styrene acrylic resin, softening point: 123 ° C.) together with binder resin, colorant, etc. In the same manner as in Example 1, a toner was obtained.

Example 23
As an external additive, instead of “Aerosil R-972”, hydrophobic silica “TG-C243” (manufactured by Cabot, average particle size 100 nm, hydrophobizing agent: hexamethyldisilazane + octyltriethoxysilane) 1.0 weight A toner was obtained in the same manner as in Example 1 except that the parts were used.

Example 24
Except for using 1 part by weight of LR-147 (Nippon Carlit Co., Ltd., boron complex of benzylic acid compound) instead of Bontron S-34 (Orient Chemical Co., Ltd.) as a negatively chargeable charge control agent In the same manner as in Example 1, a toner was obtained.

Test Example 1 [low temperature fixability]
An apparatus in which the fixing machine of the copying machine “AR-505” (manufactured by Sharp Corporation) is improved so that fixing can be performed outside the apparatus (however, for evaluation of Example 22, a non-magnetic one-component developing system printer “ The toner was mounted on “HL-2040” (manufactured by Brother Kogyo Co., Ltd.) to obtain an unfixed image.

After that, with a fixing machine (fixing speed 390mm / sec) adjusted so that the total fixing pressure is 40kgf, the fixing test of unfixed images was performed at each temperature while increasing the temperature gradually from 100 ° C to 240 ° C by 10 ° C. It was. “UNICEF Cellophane” (Mitsubishi Pencil Co., Ltd., width: 18 mm, JISZ-1522) was pasted on the fixed image, passed through a fixing roller set at 30 ° C., and then the tape was peeled off. Measure the optical reflection density before and after applying the tape using a reflection densitometer “RD-915” (manufactured by Macbeth Co.), and the ratio of both (after peeling / before sticking) first exceeds 90%. The temperature of the roller was set to the minimum fixing temperature, and the low temperature fixing property was evaluated according to the following evaluation criteria. The paper used for the fixing test is CopyBond SF-70NA (75 g / m ² ) manufactured by Sharp Corporation. The results are shown in Table 6.

〔Evaluation criteria〕
A: The minimum fixing temperature is less than 140 ° C.
B: The minimum fixing temperature is 140 ° C. or higher and lower than 170 ° C.
C: The minimum fixing temperature is 170 ° C. or higher.

Test Example 2 [Preservation]
4 g of toner was left for 72 hours in an environment of a temperature of 50 ° C. and a humidity of 60%. After standing, the degree of occurrence of toner aggregation was visually observed, and storage stability was evaluated according to the following evaluation criteria. The results are shown in Table 6.

〔Evaluation criteria〕
A: No aggregation is observed even after 72 hours.
B: Aggregation is not observed after 48 hours, but aggregation is observed after 72 hours.
C: Aggregation is observed at 48 hours.

Test Example 3 [Charge rising property]
0.6 g of toner and 19.4 g of silicone ferrite carrier (manufactured by Kanto Denka Kogyo Co., Ltd., average particle size 90 μm) are placed in a 50 mL plastic bottle and mixed for 10 minutes at 250 r / min using a ball mill, at 1 minute and 10 minutes. The charge amount was measured using a q / m meter (manufactured by EPPING). After a predetermined mixing time, a specified amount of developer was put into a cell attached to the q / m meter, and only the toner was sucked through a sieve having a mesh size of 32 μm (stainless steel, twill, wire diameter: 0.0035 mm) for 90 seconds. The voltage change on the carrier generated at that time was monitored, and the charge rising property was evaluated according to the following evaluation criteria. The results are shown in Table 6.

〔Evaluation criteria〕
The value of (charge amount at 1 minute of mixing time) / (charge amount at 10 minutes of mixing time) is A: 0.95 or more B: 0.90 or more and less than 0.95 C: 0.85 or more and less than 0.90 D: Less than 0.85

  From the above results, the toners of Examples 1 to 25 containing, as a binder resin, a polyester obtained by using a specific aromatic compound in at least one of a crystalline resin and an amorphous resin are Comparative Example 1. It can be seen that, in comparison with the toners of 4 to 4, both the low-temperature fixability and the storage stability of the toner are good, and the toner has excellent charge rising properties.

  The binder resin for electrophotographic toner of the present invention is suitably used as a binder resin for toner used for developing a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method and the like.

Claims (7)

A binder resin for an electrophotographic toner comprising an amorphous resin and a crystalline resin, wherein both the amorphous resin and the crystalline resin are obtained by condensation polymerization of an alcohol component and a carboxylic acid component. And at least one of the amorphous resin and the crystalline resin is represented by the formula (I):

(Wherein R ¹ represents a hydrogen atom, a hydroxyl group or a methoxy group, and X represents a hydroxyl group or a carboxyl group which may have a hydrogen atom, an aldehyde group, an allyl group, a vinyl group, a methoxy group or a linking group. Show.)
A binder resin for an electrophotographic toner, which is a resin obtained by using an aromatic compound represented by formula (I) as a carboxylic acid component and / or an alcohol component.   The binder resin according to claim 1, wherein the linking group in X is a divalent hydrocarbon group having 2 to 4 carbon atoms.   The aromatic compound represented by the formula (I) contains at least one hydroxycarboxylic acid selected from the group consisting of ferulic acid, 5-hydroxyferulic acid, sinapinic acid, vanillic acid and syringic acid. Or the binder resin of 2.   The crystalline resin is a polycondensation resin containing an aromatic compound represented by the formula (I) as a carboxylic acid component and / or an alcohol component, and the content of the aromatic compound represented by the formula (I) is The binder resin according to claim 1, which is 0.5 to 40 mol% in the raw material monomer of the crystalline resin.   The amorphous resin is a polycondensation resin containing an aromatic compound represented by the formula (I) as a carboxylic acid component and / or an alcohol component, and the content of the aromatic compound represented by the formula (I) Is a binder resin according to any one of claims 1 to 4, which is 0.5 to 80 mol% in the raw material monomer of the amorphous resin.   An electrophotographic toner comprising the binder resin according to claim 1. Formula (I):

(Wherein R ¹ represents a hydrogen atom, a hydroxyl group or a methoxy group, and X represents a hydroxyl group or a carboxyl group which may have a hydrogen atom, an aldehyde group, an allyl group, a vinyl group, a methoxy group or a linking group. Show.)
A crystalline resin for an electrophotographic toner obtained by using the aromatic compound represented by formula (I) as a carboxylic acid component and / or an alcohol component.