JP2010072215A - Toner for electrophotography - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crystalline polyester for a toner which obtains a toner excellent in transparency, and also to provide a toner for electrophotography. <P>SOLUTION: The crystalline polyester for a toner is obtained by the condensation polymerization of an alcohol component containing a 2-8C aliphatic diol with a carboxylic acid component containing at least one selected from an aromatic dicarboxylic acid, an alkylsuccinic acid and an alkenylsuccinic acid. The toner for electrophotography contains the crystalline polyester concerned. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a crystalline polyester for toner used in an electrophotographic method, an electrostatic recording method, an electrostatic printing method and the like, and an electrophotographic toner containing the crystalline polyester.

  In recent years, in pursuit of higher image quality, toners having excellent low-temperature fixability have been developed. For example, 70 mol% of an alcohol component containing 70 mol% of 1,6-hexanediol and an aromatic carboxylic acid compound are used. % Crystalline polyester for toner obtained by polycondensation with a carboxylic acid component contained at least% (Patent Document 1), and a binder resin for toner comprising crystalline polyester and amorphous polyester resin The crystalline polyester is obtained by condensation polymerization of 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. The softening point is a resin having a temperature of 80 to 130 ° C., and the amorphous polyester resin contains 70 mol% or less of an alkylene oxide adduct of bisphenol A. A resin having a polyester component obtained alcohol component containing the carboxylic acid component by polycondensing, a binder resin for toner (Patent Document 2) are disclosed.

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

However, when crystalline polyester is used as the binder resin, a portion with poor dispersion may occur. When this dispersion failure occurs, the crystalline polyester domain portion does not transmit light, and toner color development and transparency deteriorate. In addition, when the toner is prepared by the emulsion aggregation / unification method, the particle size of the emulsion dispersion is 0.5 μm or less, but it re-aggregates during crystallization and easily forms a large crystalline domain. And transparency deteriorates. Therefore, a crystalline polyester for toner that can obtain a toner having excellent transparency is desired.
An object of the present invention is to provide a crystalline polyester for toner and an electrophotographic toner capable of obtaining a toner having excellent transparency.

  The present invention is obtained by polycondensing an alcohol component containing an aliphatic diol having 2 to 8 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid and at least one selected from alkyl succinic acid and alkenyl succinic acid. An electrophotographic toner containing, as a binder resin, a crystalline polyester for toner and a polyester containing the crystalline polyester and an amorphous polyester.

  By using the crystalline polyester for toner of the present invention, an electrophotographic toner excellent in transparency can be provided.

The crystalline polyester of the present invention is preferably used as a binder resin for an electrophotographic toner, and the electrophotographic toner of the present invention (hereinafter also simply referred to as toner) includes the crystalline polyester and the amorphous polyester. It is preferable to contain the contained polyester as a binder resin.
Here, the crystalline polyester has a ratio of softening point to endothermic maximum peak temperature (softening point (° C.) / Peak temperature (° C.)) of 0.6 to 1.3, preferably 0.9 to 1.2. More preferably, it refers to a resin that is greater than 0.9 and less than or equal to 1.1.
Amorphous polyester is a resin having a ratio of softening point to endothermic maximum peak temperature (softening point (° C.) / Peak temperature (° C.)) of more than 1.3 and 4 or less, preferably 1.5 to 3. Say.
In the present invention, the term “polyester” means both crystalline polyester and amorphous polyester.

[Crystalline polyester]
The crystalline polyester in the present invention is a polycondensation of an alcohol component containing an aliphatic diol having 2 to 8 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid and at least one selected from alkyl succinic acid and alkenyl succinic acid. It is a resin obtained.
(Alcohol component)
In the crystalline polyester for toner of the present invention, the alcohol component contains an aliphatic diol having 2 to 8 carbon atoms from the viewpoint of enhancing crystallinity.
Examples of the aliphatic diol having 2 to 8 carbon atoms include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, neopentyl glycol, 1,4-butenediol, and the like are preferable, α, ω-linear alkanediol is particularly preferable, and 1,6-hexanediol is further included. preferable.

  The content of the aliphatic diol having 2 to 8 carbon atoms is preferably 70 mol% or more, more preferably 80 to 100 mol%, still more preferably 90 to 90 mol% in the alcohol component from the viewpoint of enhancing the crystallinity of the crystalline polyester. 100 mol%. In particular, it is desirable that one of the aliphatic diols in the alcohol component accounts for preferably 70 mol% or more, and more preferably 80 to 95 mol%. Among these, 1,6-hexanediol is preferably contained in the alcohol component in an amount of preferably 70 mol% or more, more preferably 80 to 100 mol%, and still more preferably 90 to 100 mol%.

  Examples of the polyhydric alcohol component other than the aliphatic diol having 2 to 8 carbon atoms that can be contained in the alcohol component include, for example, 2,2-bis (4-hydroxyphenyl) propane polyoxypropylene adduct, 2,2-bis Aromatic diols such as alkylene oxide adducts of bisphenol A represented by the following formula (I) such as polyoxyethylene adducts of (4-hydroxyphenyl) propane; trivalent or more such as glycerin, pentaerythritol, trimethylolpropane Of alcohol.

(In the formula, R is an alkylene group having 2 or 3 carbon atoms, x and y are positive numbers, and the sum of x and y is 1 to 16, preferably 1.5 to 5.)

(Carboxylic acid component)
In the crystalline polyester for toner of the present invention, the carboxylic acid component contains at least one selected from aromatic dicarboxylic acids, alkyl succinic acids and alkenyl succinic acids from the viewpoint of improving good low-temperature fixability and transparency. .

In the crystalline polyester for toner of the present invention, a carboxylic acid component containing an aromatic dicarboxylic acid is used from the viewpoint of low-temperature fixability of the toner.
The aromatic dicarboxylic acid used in the present invention includes an aromatic dicarboxylic acid derivative that can be converted into the same structural unit as the structural unit derived from the aromatic dicarboxylic acid by a condensation reaction. For example, aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, anhydrides of these acids, and alkyl (1 to 3 carbon atoms) esters thereof are preferably mentioned.
Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and an isopropyl group. Among these, terephthalic acid or its alkyl (C1-C3) ester is preferable from the viewpoint of charge stability and low-temperature fixability.
The content of the aromatic dicarboxylic acid is preferably 50 to 99 mol%, more preferably 70 to 99 mol%, and still more preferably 90 to 99 mol%, in the carboxylic acid component, from the viewpoint of low-temperature fixability of the toner. is there.

The crystalline polyester for toner of the present invention can provide low-temperature fixability to the toner by using a carboxylic acid component containing at least one selected from alkyl succinic acid and alkenyl succinic acid. Transparency is obtained.
Although the cause is not clear, this is because the crystalline polyester has a side chain by containing at least one selected from alkyl succinic acid and alkenyl succinic acid. In the binder resin containing the crystalline polyester, This is thought to be because this side chain is entangled with the amorphous contained in the binder resin to prevent aggregation of the crystalline polyester during crystallization, or because of the presence of the side chain, the crystallization rate becomes slow. In addition, it is considered that the side chain portion is melted quickly and the dispersibility is promoted even during the kneading of the toner.

From the viewpoint of improving the transparency of the toner based on the above inference, the alkyl group and the alkenyl group preferably have 9 to 14 carbon atoms, and more preferably have a branched chain.
Therefore, it is preferably selected from the group consisting of an alkyl succinic acid having a C 9-14 alkyl group having a branched chain, and an alkenyl succinic acid having a C 9-14 alkenyl group preferably having a branched chain. 1 or more types are preferable and 2 or more types are more preferable.

  Here, the “kind” is derived from an alkyl group or alkenyl group, and includes those having different chain lengths of carbon number of the alkyl group or alkenyl group and structural isomers. In the present invention, the structural isomers of alkyl succinic acid and alkenyl succinic acid derived from the alkyl group or alkenyl group are treated as separate alkyl succinic acid or alkenyl succinic acid.

  Specific examples of the alkyl group or alkenyl group having 9 to 14 carbon atoms having a branched chain include isododecenyl group and isododecyl group. By using a carboxylic acid component containing such an alkyl succinic acid and / or alkenyl succinic acid having an alkyl group and / or an alkenyl group having different carbon numbers having a branched chain, the transparency of the resulting crystalline polyester is improved. Further improve. In addition, the toner containing the crystalline polyester has an effect of having a very wide fixing region because, for example, the endothermic peak near the glass transition point in the differential scanning calorimetry (DSC) becomes broad.

From the viewpoint of improving the transparency of the toner, at least one selected from alkyl succinic acid and alkenyl succinic acid is alkyl succinic acid and / or carbon number 9-14 derived from an alkyl group having a branched chain having 9-14 carbon atoms. The alkenyl succinic acid derived from an alkenyl group having a branched chain is preferably 20 or more, more preferably 25 or more, and still more preferably 30 or more.
That is, the carboxylic acid component is also selected from the group consisting of the above alkyl succinic acid having a C9-14 alkyl group having a branched chain and the alkenyl succinic acid having a C9-14 alkenyl group having a branched chain. It is preferable to contain at least 20 or more, more preferably 25 or more, and still more preferably 30 or more. The types here have the same meaning as described above.

Furthermore, from the viewpoint of improving the transparency and low-temperature fixability of the toner, the alkyl succinic acid and / or alkenyl succinic acid includes an alkylene group-containing compound (alkylene compound), maleic acid, fumaric acid, and acid anhydrides thereof. Is preferably obtained from at least one selected from the group consisting of an alkylene compound and maleic acid. As the alkylene compound, those having 9 to 14 carbon atoms are preferable, and specifically, those obtained from ethylene, propylene, isobutylene, normal butylene and the like, for example, trimers and tetramers thereof are preferably used.
Alkyl succinic acid and / or alkenyl succinic acid can utilize the ene reaction by mixing and heating the known alkylene compound and at least one selected from maleic acid, fumaric acid and acid anhydrides thereof. However, from the viewpoint of ease of production, a method obtained by utilizing the ene reaction by mixing the known alkylene compound and maleic acid and heating is preferable.

  In order to obtain an alkyl succinic acid having a branched chain alkyl group having 9 to 14 carbon atoms or an branched chain alkenyl succinic acid group having 9 to 14 carbon atoms, any known method can be used. . For example, selection of the raw material or catalyst type of the alkylene compound used in the synthesis of the alkylene compound, a method of adjusting the reaction rate, reaction time, reaction pressure, solvent, etc., and production of alkyl succinic acid and / or alkenyl succinic acid Any of the methods for adjusting the distillation conditions can be used (see JP-A-48-23405, JP-A-48-23404, US Pat. No. 3,374,285, etc.).

Suitable raw materials used for the synthesis of the alkylene compound include propylene and isobutylene. From the viewpoint of increasing the number of structural isomers, propylene having a small molecular weight is more preferable.
Suitable catalysts used for the synthesis of the alkylene compound include liquid phosphoric acid, solid phosphoric acid, tungsten, boron trifluoride complex and the like. From the viewpoint of ease of control of the number of structural isomers, a method of adjusting by distillation after random polymerization is preferred.
The total content of alkyl succinic acid and alkenyl succinic acid in the carboxylic acid component is preferably 1 to 30 mol%, more preferably 5 to 25 mol%, and still more preferably 10 from the viewpoint of toner transparency. ~ 20 mol%.

  In the present invention, other divalent or trivalent or higher carboxylic acid components can be used as the carboxylic acid component together with the aromatic dicarboxylic acid, alkyl succinic acid and alkenyl succinic acid. Examples of the divalent carboxylic acid include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, adipic acid, an alkyl group having 1 to 8 carbon atoms or 15 or more carbon atoms. Examples thereof include aliphatic dicarboxylic acids such as succinic acid substituted with 2 to 8 or 15 or more alkenyl groups, anhydrides of these acids, and alkyl (carbon number 1 to 3) esters of these acids.

Examples of the trivalent or higher polyvalent carboxylic acid compounds include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and aromatic carboxylic acids such as pyromellitic acid, and these Derivatives such as acid anhydrides and alkyl (1 to 3 carbon atoms) esters may be mentioned. Among the trivalent or higher polyvalent carboxylic acid compounds, trimellitic acid and its acid anhydride are preferable from the viewpoint of being inexpensive and easy to control the reaction.
Furthermore, from the viewpoint of molecular weight adjustment and the like, a monovalent alcohol or a monovalent carboxylic acid compound may be appropriately contained in the alcohol component and / or carboxylic acid component as long as the effects of the present invention are not impaired.

At least one selected from aromatic dicarboxylic acid, alkyl succinic acid and alkenyl succinic acid, and aliphatic diol having 2 to 8 carbon atoms in the total number of moles of the carboxylic acid component and alcohol component which constitute the crystalline polyester Is preferably 75 to 100 mol%, more preferably 85 to 100 mol%, from the viewpoint of excellent low-temperature fixability and transparency of the toner.
The molar ratio of the carboxylic acid component to the alcohol component (carboxylic acid component / alcohol component) in the crystalline polyester is preferably higher in the alcohol component than in the carboxylic acid component when increasing the molecular weight of the crystalline polyester. Furthermore, from the viewpoint that the molecular weight of the polyester can be easily adjusted by distilling off the alcohol component during the vacuum reaction, 0.9 or more and less than 1 is preferable, and 0.95 or more and less than 1 is more preferable.

In the present invention, the number average molecular weight of the crystalline polyester is preferably 2,000 or more, and more preferably 4,000 or more, from the viewpoint of the transparency of the toner. However, considering the productivity of the crystalline polyester, the number average molecular weight is preferably 10,000 or less, more preferably 9,000 or less, and further preferably 8,000 or less.
Further, from the same viewpoint as the number average molecular weight, the weight average molecular weight is preferably 9,000 or more, more preferably 20,000 or more, still more preferably 60,000 or more, and preferably 10,000,000 or less. Preferably it is 6,000,000 or less, more preferably 4,000,000 or less, particularly preferably 1,000,000 or less.
In the present invention, the number average molecular weight and the weight average molecular weight of the crystalline polyester are both values obtained by measuring the chloroform-soluble content.

In order to obtain such a high molecular weight crystalline polyester, as described above, the molar ratio of the carboxylic acid component and the alcohol component is adjusted, the reaction temperature is increased, the amount of the catalyst is increased, and dehydration is performed for a long time under reduced pressure. What is necessary is just to select reaction conditions, such as performing reaction. A high-power motor can be used to produce a high molecular weight crystalline polyester. However, when producing without particularly selecting production equipment, the raw material monomer is used as a non-reactive low-viscosity resin or solvent. The method of reacting together is also an effective means.
The softening point of the crystalline polyester is preferably from 80 to 160 ° C, more preferably from 80 to 140 ° C, further preferably from 90 to 130 ° C, and further preferably from 100 to 120 ° C, from the viewpoint of low-temperature fixability and transparency of the toner. .
The melting point of the crystalline polyester is preferably from 70 to 130 ° C, more preferably from 80 to 110 ° C, and further preferably from 90 to 100 ° C, from the viewpoint of low-temperature fixability and transparency of the toner.
The softening point and melting point can be easily adjusted by adjusting the raw material monomer composition, the polymerization initiator, the molecular weight, the catalyst amount, etc., or by selecting the reaction conditions.

[Amorphous polyester]
The crystalline polyester for toner of the present invention is preferably used as a binder resin together with the amorphous polyester from the viewpoint of maintaining the melt viscosity at the time of melt kneading in toner production, for example.
The amorphous polyester preferably contains a polyester component obtained by condensation polymerization of an alcohol component and a carboxylic acid component.

(Alcohol component)
In the present invention, the amorphous polyester contains a polyester component obtained by polycondensing an alcohol component containing 70 mol% or more of an alkylene oxide adduct of bisphenol A represented by the formula (I) and a carboxylic acid component. It is preferable to be a resin.
The content of the alkylene oxide adduct of bisphenol A is preferably 70 mol% or more, more preferably 80 to 100 mol%, still more preferably 90 to 100 mol% in the alcohol component. In the present invention, environmental stability is improved by the alkylene oxide adduct of bisphenol A.
Examples of the alcohol other than the alkylene oxide adduct of bisphenol A that can be contained in the alcohol component include the same polyhydric alcohols as those used for the crystalline polyester.

(Carboxylic acid component)
Like the crystalline polyester, the carboxylic acid component contains at least one selected from alkyl succinic acid and alkenyl succinic acid to increase the dispersion of the crystalline polyester in the amorphous polyester, It is preferable from the viewpoint of improving transparency. As the alkyl succinic acid and alkenyl succinic acid, as described above, an alkyl succinic acid having a branched chain, preferably an alkyl group having 9 to 14 carbon atoms, and preferably having a branched chain, having 9 to 14 carbon atoms. One or more selected from the group consisting of alkenyl succinic acids having an alkenyl group is preferable, and two or more are more preferable.

The total content of alkyl succinic acid and alkenyl succinic acid is preferably 5 to 40 mol%, more preferably 10 to 35 mol%, and still more preferably 15 to 30 mol% in the carboxylic acid component.
Furthermore, it is preferable to contain the above-mentioned aromatic dicarboxylic acid compound, especially terephthalic acid, and the content of the aromatic dicarboxylic acid compound is preferably 30 to 95 mol%, more preferably 40 to 90 in the carboxylic acid component. It is mol%, More preferably, it is 50-85 mol%.
Examples of the polyvalent carboxylic acid compound that can be contained in addition to the aromatic dicarboxylic acid compound include the same polyvalent carboxylic acid compounds as those used for the crystalline polyester.

(Polyester modified resin)
In the present invention, the amorphous polyester containing the polyester component obtained by condensation polymerization of the alcohol component and the carboxylic acid component includes not only the polyester component but also a polyester-modified resin.
Examples of the polyester-modified resin include a urethane-modified polyester obtained by modifying a polyester with a urethane bond, an epoxy-modified polyester obtained by modifying a polyester with an epoxy bond, and a hybrid resin having two or more resin components including a polyester component. It is done.
As the amorphous polyester, either the polyester component or its modified resin may be used, or both may be used together. Specifically, the polyester component and / or a hybrid having a polyester component and a vinyl resin component Resin may be used.

  A hybrid resin having a polyester component and a vinyl resin component is prepared by a method of melt-kneading each resin in the presence of an initiator or the like, a method of dissolving and mixing each resin in a solvent, It may be produced by any method such as a method of polymerizing the raw material monomer mixture. Preferably, it is a resin obtained by the method of performing a polycondensation reaction and an addition polymerization reaction using the raw material monomer of the said polyester component, and the raw material monomer of a vinyl resin component (Unexamined-Japanese-Patent No. 7-98518).

Raw material monomers for vinyl resin components include styrene compounds such as styrene and α-methylstyrene; ethylenically unsaturated monoolefins such as ethylene and propylene; diolefins such as butadiene; halovinyls such as vinyl chloride; vinyl acetate Vinyl esters such as vinyl propionate; alkyl (carbon number 1 to 18) esters of (meth) acrylic acid; esters of ethylenic monocarboxylic acids such as dimethylaminoethyl (meth) acrylate; vinyl ethers such as vinyl methyl ether And vinylidene halides such as vinylidene chloride; N-vinyl compounds such as N-vinylpyrrolidone and the like. Styrene, butyl acrylate, 2-ethylhexyl acrylate, and methyl methacrylate are preferred from the viewpoints of reactivity, grindability, and charge stability, and alkyl ester of styrene and / or (meth) acrylic acid is a vinyl resin component. The content is preferably 50% by weight or more, more preferably 80 to 100% by weight.
In addition, when polymerizing the raw material monomer of a vinyl-type resin component, you may use a polymerization initiator, a crosslinking agent, etc. as needed.

  The weight ratio of the raw material monomer of the polyester component to the raw material monomer of the vinyl resin component (the raw material monomer of the polyester component / the raw material monomer of the vinyl resin component) is preferably 55/45 from the viewpoint of forming a continuous phase with the polyester component. 95/5, more preferably 60/40 to 95/5, and 70/30 to 90/10 are even more preferable.

The softening point of the amorphous polyester is preferably 70 to 180 ° C., more preferably 100 to 160 ° C. from the viewpoint of low-temperature fixability of the toner, and the glass transition temperature is preferably 45 from the viewpoint of low-temperature fixability of the toner. It is -80 degreeC, More preferably, it is 55-75 degreeC. The glass transition temperature is a physical property unique to amorphous polyester, and is distinguished from the maximum peak temperature of heat of fusion.
The number average molecular weight of the amorphous polyester is preferably 1,000 to 6,000, and more preferably 2,000 to 5,000. The weight average molecular weight is preferably 10,000 or more, more preferably 30,000 or more, and preferably 1,000,000 or less. The number average molecular weight and the weight average molecular weight of the amorphous polyester are both values obtained by measuring the tetrahydrofuran soluble content.

(Condensation conditions)
In any of the crystalline polyester and the amorphous polyester, the condensation polymerization of the alcohol component and the carboxylic acid component is preferably performed in the presence of an esterification catalyst. Examples of the esterification catalyst suitably used for the condensation polymerization include a titanium compound and a tin (II) compound having no Sn-C bond, and these can be used alone or in combination.
As a titanium compound, the titanium compound which has a Ti-O bond is preferable, and the compound which has a C1-28 total carbon number alkoxy group, an alkenyloxy group, or an acyloxy group is more preferable.

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) 1 (} C 3 ₇ O) _3], and titanium monopropylate tris (triethanolaminate) _{[Ti (C 6 H 14 O 3} N) 3 (C 3 H 7 O) 1 ], and the like. Among these, titanium diisopropylate bistriethanolamate, titanium diisopropylate bisdiethanolamate, and titanium dipentylate bistriethanolamate are preferable, and are also available as, for example, commercial products of Matsumoto Trading Co., Ltd.

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, tetramyristyl titanate, tetraoctyl titanate, and dioctyl dihydroxy octyl titanate are preferable, and these can be obtained by reacting, for example, titanium halide with a corresponding alcohol. It is also available as a commercial product.

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. Preferred examples include tin (II) compounds having a Sn-O bond.
Examples of tin (II) compounds having a Sn-O bond include tin (II) oxalate, tin (II) diacetate, tin (II) dioctanoate, tin (II) dilaurate, tin (II) distearate, and Tin (II) carboxylate having a carboxylic acid group having 2 to 28 carbon atoms such as tin (II) dioleate; dioctyloxytin (II), dilauroxytin (II), distearoxytin (II), and dioleoxytin (II) Dialkoxytin (II) having an alkoxy group having 2 to 28 carbon atoms, such as tin oxide (II) and tin sulfate (II). Examples of the compound having a Sn-X (X represents a halogen atom) bond include tin (II) halides such as tin (II) chloride and tin (II) bromide. Among these, fatty acid tin (II) represented by (R ¹ COO) ₂ Sn (wherein R ¹ represents an alkyl group or alkenyl group having 5 to 19 carbon atoms) from the viewpoint of the charge rising effect and catalytic ability. ), (R ² O) ₂ Sn (wherein R ² represents an alkyl group or alkenyl group having 6 to 20 carbon atoms), and tin oxide (II) represented by SnO Fatty acid tin (II) and tin (II) oxide represented by (R ¹ COO) ₂ Sn are more preferred, tin (II) dioctanoate, tin (II) distearate, and tin (II) oxide Is more preferably used.
The titanium compound and the tin (II) compound can be used alone or in combination of two or more.

The amount of the esterification catalyst present is preferably 0.01 to 1.0 part by weight, more preferably 0.1 to 0.6 part by weight based on 100 parts by weight of the total amount of the alcohol component and the carboxylic acid component.
The polycondensation of the alcohol component and the carboxylic acid component can be performed, for example, at a temperature of 120 to 250 ° C. in an inert gas atmosphere in the presence of the esterification catalyst.
Specifically, for example, all monomers are charged at once to increase the strength of the resin, or divalent monomers are first reacted to reduce low molecular weight components, and then trivalent or higher monomers are added to react. You may use the method of making it. Further, the reaction may be accelerated by reducing the pressure of the reaction system in the latter half of the polymerization.

The acid value of the crystalline polyester and the amorphous polyester is preferably 1 to 40 mgKOH / g, more preferably 2 to 35 mgKOH / g, from the viewpoint of good chargeability and hydrolysis resistance of the toner. More preferred is 30 mg KOH / g.
Furthermore, it is preferable that the crystalline polyester and the amorphous polyester have excellent solubility in an organic solvent.
The weight ratio of the crystalline polyester to the amorphous polyester (crystalline polyester / amorphous polyester) of the present invention is preferably 5/95 to 50/50 from the viewpoint of low-temperature fixability and transparency. -40/60 is more preferable, and 15 / 85-35 / 65 is more preferable.

[Binder resin contained in toner]
In the toner of the present invention, it is preferable to use a polyester containing the crystalline polyester and the amorphous polyester as a binder resin.
The binder resin may contain other resins other than the crystalline polyester of the present invention and the amorphous polyester as long as the present invention is not impaired.
The toner of the present invention includes, for example, a step of forming particles of the above-described binder resin and a raw material component containing an additive as necessary in the process of aggregation and coalescence, as will be described later. Is preferably obtained.

(Additive)
Examples of additives that can be contained as necessary include colorants, charge control agents, mold release agents, conductivity modifiers, extender pigments, reinforcing fillers such as fibrous substances, antioxidants, and anti-aging agents. Agents and the like. These can also be used as an aqueous dispersion.
There is no restriction | limiting in particular as a coloring agent, A well-known coloring agent is mentioned, According to the objective, it can select suitably. Specifically, carbon black, inorganic composite oxide, chrome yellow, hansa yellow, benzidine yellow, sren yellow, quinoline yellow, permanent orange GTR, pyrazolone orange, vulcan orange, watch young red, permanent red, brilliantamine 3B, Brilliantamine 6B, DuPont Oil Red, Pyrazolone Red, Resol Red, Rhodamine B Lake, Lake Red C, Bengal, Aniline Blue, Ultramarine Blue, Calco Oil Blue, Methylene Blue Chloride, Phthalocyanine Blue, Phthalocyanine Green, Malachite Green Oxalate, etc. Various pigments: acridine, xanthene, azo, benzoquinone, azine, anthraquinone, indico, Indigo dyes, phthalocyanine, aniline black, can be polymethine dyes, triphenylmethane dyes, diphenylmethane dyes, thiazine dyes, and using various dyes thiazole, etc. in combination alone or in combination. The content of the colorant is preferably 0.1 to 20 parts by weight and more preferably 1 to 10 parts by weight with respect to 100 parts by weight of the binder resin.

  Examples of charge control agents include chromium azo dyes, iron azo dyes, aluminum azo dyes, and salicylic acid metal complexes. Various charge control agents may be used alone or in combination of two or more. The content of the charge control agent is preferably 0.1 to 8 parts by weight and more preferably 0.5 to 7 parts by weight with respect to 100 parts by weight of the binder resin.

Release agents include fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide; plant waxes such as carnauba wax, rice wax, candelilla wax, wood wax, and jojoba oil; Animal waxes such as beeswax; Waxes of mineral and petroleum waxes such as montan wax, ozokerite, ceresin, microcrystalline wax, and Fischer-Tropsch wax; polyolefin wax, paraffin wax, silicones, etc. Good. The melting point of the release agent is preferably 60 to 140 ° C., more preferably 60 to 100 ° C. from the viewpoints of fixability and offset resistance. Each mold release agent may be used alone or in combination of two or more.
The content of the release agent is preferably 0.5 to 10 parts by weight, more preferably 1 to 8 parts by weight with respect to 100 parts by weight of the binder resin, from the viewpoint of dispersibility in the binder resin. More preferably, it is 5 to 7 parts by weight.

[Toner Production Method]
The toner of the present invention is not particularly limited as long as it can be obtained using the crystalline polyester.
For example, a radical polymerizable monomer solution in which a binder resin is dissolved is emulsion-polymerized to obtain resin fine particles, and the resin fine particles are fused in an aqueous medium (see Japanese Patent Application Laid-Open No. 2001-42568); A method in which a resin heated melt composed of a resin-containing raw material is dispersed in an aqueous medium not containing an organic solvent while maintaining the molten state of the binder resin, and then dried (see JP 2001-235904 A). The additives such as the binder resin and the colorant are uniformly mixed with a mixer such as a Henschel mixer, and then melt-kneaded with a closed kneader or a single or twin screw extruder, and then cooled, pulverized, and classified. Methods and the like. The production method described below is preferred.

(Manufacture of resin particles)
The toner of the present invention can be obtained, for example, by (A) a method obtained by mixing, aggregating and coalescing an aqueous dispersion containing crystalline polyester particles and an aqueous dispersion containing amorphous polyester particles, or (B) It is preferably obtained by a method obtained by agglomerating and coalescing an aqueous dispersion of mixed polyester particles containing a crystalline polyester and an amorphous polyester. Specifically, it is a production method including the following steps.

<Method (A)>
Step a-1: polycondensing an alcohol component containing an aliphatic diol having 2 to 8 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid and at least one selected from alkyl succinic acid and alkenyl succinic acid A step of obtaining an aqueous dispersion of the obtained crystalline polyester particles and an aqueous dispersion of amorphous polyester particles;
Step a-2: A step of mixing the aqueous dispersion of crystalline polyester obtained in Step a-1 and the aqueous dispersion of amorphous polyester and aggregating them to obtain an aqueous dispersion of resin particles,
Step a-3: Step of uniting the resin particles obtained in step a-2

<Method (B)>
Step b-1: polycondensation of an alcohol component containing an aliphatic diol having 2 to 8 carbon atoms and a carboxylic acid component containing an aromatic dicarboxylic acid and at least one selected from alkyl succinic acid and alkenyl succinic acid A step of obtaining an aqueous dispersion of mixed polyester particles containing the obtained crystalline polyester and amorphous polyester;
Step b-2: A step of aggregating the aqueous dispersion of mixed polyester particles obtained in Step b-1 to obtain an aqueous dispersion of resin particles,
Step b-3: Step of uniting the resin particles obtained in step b-2

Each process in the said method (A) and (B) is demonstrated in detail.
In the present specification, the aqueous system may contain a solvent such as an organic solvent, but water is preferably 50% by weight or more, preferably 70% by weight or more, more preferably 90% by weight or more. Preferably it contains 99% by weight or more.

<Step a-1>
Step a-1 is a step of separately producing an aqueous dispersion of crystalline polyester particles and an aqueous dispersion of amorphous polyester particles.
An aqueous dispersion of crystalline polyester particles or an aqueous dispersion of amorphous polyester particles is obtained after mixing and stirring a crystalline or amorphous polyester, an organic solvent and water, if necessary, and a neutralizing agent. The organic solvent can be removed from the obtained dispersion.
Preferably, crystalline polyester or amorphous polyester is dissolved in an organic solvent, and then water and, if necessary, a neutralizing agent are mixed.
The weight ratio of the crystalline polyester or amorphous polyester to the organic solvent is preferably 100 to 1000 parts by weight of the organic solvent with respect to 100 parts by weight of the crystalline polyester or amorphous polyester, and the weight of the organic solvent and water. The ratio is preferably 100 to 1000 parts by weight of water with respect to 100 parts by weight of the organic solvent.

Examples of the organic solvent include alcohol solvents such as ethanol, isopropanol, and isobutanol; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and diethyl ketone; ether solvents such as dibutyl ether, tetrahydrofuran, and dioxane. . In particular, methyl ethyl ketone and methyl isobutyl ketone are preferable.
When stirring the mixture, a commonly used mixing and stirring device such as an anchor blade can be used. Examples of the neutralizing agent include alkali metals such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; organic bases such as ammonia, trimethylamine, ethylamine, diethylamine, triethylamine, triethanolamine, and tributylamine.
The solid content concentration of the aqueous dispersion of the obtained polyester particles is preferably 3 to 50%, more preferably 5 to 30%, and still more preferably 7 to 15%.

The aqueous dispersion of polyester particles can also be made into a dispersion without using an organic solvent. This is because when the polyester is mixed with a nonionic surfactant, the viscosity of the resulting mixture is reduced, and the decrease in the viscosity of the mixture is compatible with the polyester, This is because the softening point of the polyester apparently decreases. By utilizing this phenomenon, the apparent softening point of the polyester compatible with the nonionic surfactant can be lowered below the boiling point of water. Even if the resin alone has a melting point or softening point of 100 ° C. or higher, By dropping water at normal pressure, a dispersion in which the polyester is dispersed in water can be obtained.
This method requires at least water and a nonionic surfactant, so it can be applied to resins that are insoluble in organic solvents, and does not require the burden of equipment for recovering organic solvents and maintaining the work environment. Since a special device required when using mechanical means is not required, there is an advantage that a resin particle dispersion can be produced economically.

  Nonionic surfactants include, for example, polyoxyethylene alkyl allyl ethers such as polyoxyethylene nonylphenyl ether, polyoxyethylene oleyl ether, and polyoxyethylene lauryl ether; polyoxyethylene alkyl ethers; polyoxyethylene sorbitan Polyoxyethylene sorbitan esters such as monolaurate and polyoxyethylene sorbitan monostearate; Polyoxyethylene fatty acid esters such as polyethylene glycol monolaurate, polyethylene glycol monostearate, and polyethylene glycol monooleate An oxyethylene / oxypropylene block copolymer and the like. In addition, an anionic surfactant or a cationic surfactant may be used in combination with the nonionic surfactant.

  As the nonionic surfactant, it is preferable to select a nonionic surfactant having good compatibility with the polyester. In order to obtain a stable polyester dispersion, the HLB of the nonionic surfactant is preferably 12 to 18, and depending on the type of polyester, two or more different HLB nonionic surfactants are used. It is more preferable. For example, in the case of a highly hydrophilic resin, at least one nonionic surfactant having an HLB of 12 to 18 may be used. In the case of a highly hydrophobic resin, a low HLB, for example, 7 to 10 is used. It is preferable to adjust the weighted average of both HLBs to 12 to 18 by using those having the same level and those having a high HLB, for example, 14 to 20 in combination. In this case, it is presumed that those having an HLB of about 7 to 10 can compatibilize the resin, and those having a high HLB can stabilize the dispersion of the resin in water.

The clouding point of the nonionic surfactant is preferably 70 to 105 ° C, more preferably 80 to 105 ° C when the polyester is atomized under normal pressure and water.
The amount of the nonionic surfactant used is preferably 5 parts by weight or more with respect to 100 parts by weight of the total amount of the crystalline polyester and the amorphous polyester, from the viewpoint of lowering the melting point of the polyester. From the viewpoint of controlling the ionic surfactant, 80 parts by weight or less is preferable. Therefore, from the viewpoint of making these compatible, the amount of the nonionic surfactant used is preferably 5 to 80 parts by weight, more preferably 10 to 70 parts by weight, with respect to 100 parts by weight of the polyester, and 20 to 60 parts by weight. Is more preferable.

<Step b-1>
Step b-1 is a step of obtaining an aqueous dispersion of mixed polyester particles containing a crystalline polyester and an amorphous polyester. A preferable mixing weight ratio of the crystalline polyester and the amorphous polyester is as described above.
In step b-1, as a method for obtaining a mixed polyester, (i) a method using a mixed polyester in which a crystalline polyester and an amorphous polyester are heated and mixed in advance, (ii) a crystalline polyester and an amorphous polyester are used. The method of using the mixed polyester which melt-mixed polyester in the organic solvent previously is mentioned. When using the organic solvent when manufacturing the aqueous dispersion liquid of the process 2, the method using (ii) is easy. When no organic solvent is used, the organic solvent may be removed.

By producing the mixed polyester in this way, it is possible to obtain resin particles having very high dispersibility in which crystalline polyester and amorphous polyester are mixed in the particles.
The aqueous dispersion of mixed polyester particles is prepared by mixing the mixed polyester obtained in (i) above, an organic solvent and water, and further mixing with a neutralizing agent as necessary, and then removing the organic solvent from the obtained dispersion. Can be obtained.
Preferably, after the mixed polyester is dissolved in an organic solvent, water and, if necessary, a neutralizing agent are mixed.
Alternatively, the crystalline polyester and the amorphous polyester are dissolved and mixed in an organic solvent, and after performing the above (ii) to obtain a mixed polyester, after mixing with water and, if necessary, a neutralizing agent and stirring, It can be obtained by removing the organic solvent from the obtained dispersion.

The weight ratio of the mixed polyester to the organic solvent is preferably 100 to 1000 parts by weight of the organic solvent with respect to 100 parts by weight of the mixed polyester, and the weight ratio of the organic solvent to water is 100 parts by weight of the organic solvent. The amount of water is preferably 100 to 1000 parts by weight.
About the organic solvent to be used, a neutralizing agent, and other various conditions, it carries out similarly to <process a-1>, and can obtain the aqueous dispersion of mixed polyester particle | grains.
<Step a-1> In the aqueous dispersion obtained in <Step b-1>, the average particle size of the polyester particles or mixed polyester particles is from the viewpoint of uniformly agglomerating in <Step a-2 and Step b-2>. The volume median particle size is preferably 0.05 to 2 μm, more preferably 0.05 to 1 μm, and still more preferably 0.05 to 0.8 μm.

<Step a-2 and step b-2>
Step a-2 mixes the aqueous dispersion of crystalline polyester particles and the aqueous dispersion of amorphous polyester particles obtained in Step a-1, and agglomerates the crystalline polyester particles and the amorphous polyester particles. This is an aggregating step for obtaining an aqueous dispersion of resin particles, that is, agglomerated particles. In step a-2, the preferred mixing weight ratio of the aqueous dispersion of crystalline polyester particles obtained in step a-1 and the aqueous dispersion of amorphous polyester particles is as described above.
Step b-2 is an agglomeration step in which the mixed polyester particles in the aqueous dispersion of mixed polyester particles obtained in step b-1 are aggregated to obtain resin particles, that is, an aqueous dispersion of aggregated particles.
Furthermore, in step a-2 and step b-2 (hereinafter referred to as step 2), additives such as the colorant, the charge control agent, and the release agent may be added.

In the aggregation step, the solid content concentration in the system is preferably 5 to 50% by weight, more preferably 5 to 30% by weight, and further preferably 5 to 20% by weight in order to cause uniform aggregation.
The pH in the system in the aggregation step is preferably 2 to 10, more preferably 2 to 9, and even more preferably 3 to 8, from the viewpoint of achieving both the dispersion stability of the mixed solution and the aggregation property of the resin particles.
From the same viewpoint, the temperature in the system in the aggregation step is preferably not less than the softening point of the binder resin −60 ° C. (temperature lower by 60 ° C. than the softening point, hereinafter the same) and not more than the softening point.

In addition, additives such as a colorant and a charge control agent may be mixed in advance with a crystalline polyester, an amorphous polyester or a mixed polyester when preparing resin particles, and each additive is separately added to a dispersion medium such as water. A dispersion liquid dispersed therein may be prepared, mixed with resin particles, and subjected to an aggregation step. When the additive is added to the crystalline polyester, amorphous polyester or mixed polyester in advance when preparing the resin particles, the crystalline polyester, amorphous polyester or mixed polyester and additive are melt-kneaded in advance. It is preferable.
For melt kneading, it is preferable to use an open roll type biaxial kneader. The open roll type twin-screw kneader is a kneader in which two rolls are arranged close to each other in parallel, and a heating function or a cooling function can be imparted by passing a heat medium through each roll. Therefore, the open roll type twin screw kneader is an open type part to be melt kneaded, and is provided with a heating roll and a cooling roll. The heat of kneading generated can be easily dissipated.

In the aggregation process, an aggregating agent can be added in order to effectively perform aggregation. As the aggregating agent, a quaternary salt cationic surfactant and polyethyleneimine are used in the organic system, and an inorganic metal salt and a divalent or higher metal complex are used in the inorganic system. Examples of the inorganic metal salt include metal salts such as sodium sulfate, sodium chloride, calcium chloride, calcium nitrate, barium chloride, magnesium chloride, zinc chloride, aluminum chloride, and aluminum sulfate; polyaluminum chloride, polyaluminum hydroxide, and Examples thereof include inorganic metal salt polymers such as calcium polysulfide.
The amount of the flocculant used is preferably 30 parts by weight or less, more preferably 20 parts by weight or less, and even more preferably 10 parts by weight or less with respect to 100 parts by weight of the binder resin from the viewpoint of environmental resistance characteristics of the toner.
The flocculant is preferably added after being dissolved in an aqueous medium, and is preferably sufficiently stirred at the time of addition of the flocculant and after completion of the addition.

In Step 2, a mixture of an aqueous dispersion of crystalline polyester particles and an aqueous dispersion of amorphous polyester particles or an aqueous dispersion of mixed polyester particles and various additives used as necessary is uniformly dispersed. From the viewpoint, the dispersion treatment is performed at a temperature lower than the softening point of the binder resin. A uniform resin dispersion is prepared by a dispersion treatment at a temperature below the softening point of the binder resin, preferably 50 ° C lower than the softening point (hereinafter referred to as "softening point-50 ° C"). Can do. Further, the lower limit temperature of the dispersion treatment is preferably higher than 0 ° C., more preferably 10 ° C. or higher, from the viewpoint of fluidity of the medium and production energy of the resin emulsion. In the present invention, since crystalline polyester and amorphous polyester are used as the binder resin, the softening point of the mixed resin mixed and melted at the mixing ratio is defined as the softening point of the binder resin (hereinafter the same). ). Moreover, when using a masterbatch, it is set as the softening point of mixed resin including the resin used for it.
Specifically, in a basic aqueous medium containing a surfactant, for example, resin particles having an acid group such as polyester, together with additives such as a colorant, are below the softening point of the resin particles, for example, about 10 to 50 ° C. A uniform resin dispersion can be prepared by an ordinary method such as stirring at a temperature of 5 ° C. for dispersion treatment.

As a dispersion method, ultra disperser (Asada Tekko Co., Ltd., trade name), Ebara Milder (Ebara Manufacturing Co., Ltd., trade name), TK homomixer (Primics Co., Ltd., trade name), etc. (Izumi Food Machinery Co., Ltd., trade name), homovalve type high-pressure homogenizer represented by Minilab 8.3H type (Rannie, trade name), microfluidizer (Microfluidics, trade name), and Nanomizer (Nanomizer Co., Ltd.) , Trade name) and other chamber type high-pressure homogenizers.
The amount of the aqueous medium used is preferably 100 to 3000 parts by weight, preferably 400 to 3000 parts by weight with respect to 100 parts by weight of the total amount of the crystalline polyester and the amorphous polyester, from the viewpoint of obtaining uniform aggregated particles in the subsequent steps. Is more preferable, and 800 to 3000 parts by weight is even more preferable.

The average particle size of the resin particles is uniformly united in the subsequent steps, and from the viewpoint of producing toner particles, the volume median particle size is preferably 1 to 10 μm, more preferably 2 to 8 μm, and even more preferably 3 to 7 μm. .
In the present invention, the volume median particle size of the resin particles can be measured by a laser diffraction type particle size measuring machine or the like.

<Step a-3 and step b-3>
Step a-3 is a step of uniting the resin particles obtained in step a-2.
Step b-3 is a step of uniting the resin particles obtained in step b-2.
In step a-3 and step b-3 (hereinafter referred to as step 3), the coalescing step is as follows.

In the coalescing step, the aggregated particles obtained in the aggregation step are heated and united.
The temperature in the system in the coalescence process is from the viewpoint of the target toner particle size, particle size distribution, shape control, and particle fusing property, the softening point of the binder resin is −30 ° C. or higher, and the softening point + 10 ° C. or lower. The softening point is more preferably −25 ° C. or higher and the softening point + 10 ° C. or lower, and the softening point −20 ° C. or higher and the softening point + 10 ° C. or lower is still more preferable. The stirring speed is preferably a speed at which the aggregated particles do not settle.

(Manufacture of core-shell particles)
In the present invention, a toner containing core-shell particles in which the core part is obtained by the method (A) or the method (B) and the shell part is amorphous polyester is also preferable.
That is, the core part is obtained by aggregating an aqueous dispersion containing an aqueous dispersion containing crystalline polyester particles and an aqueous dispersion containing amorphous polyester particles, and the shell part is amorphous. The toner for electrophotography containing a core-shell particle as a binder resin, or the core part, which is polyester, is obtained by aggregating an aqueous dispersion of mixed polyester particles containing a crystalline polyester and an amorphous polyester. An electrophotographic toner containing core-shell particles as a binder resin, in which the shell portion is amorphous polyester, is also preferable.

Before the step 3, the core-shell particles are mixed with the aqueous dispersion of resin particles obtained in the step 2 and the aqueous dispersion of amorphous polyester particles obtained in the same manner as in the step a-1. And agglomerating to obtain an aqueous dispersion of the resin particles A, and combining the resin particles A in the same manner as in Step 3 above.
Thereby, the core-shell particle whose core part is polyester containing amorphous polyester and crystalline polyester and whose shell part is amorphous polyester can be manufactured. By using amorphous polyester for the shell portion, the low-temperature fixability is further improved and the storage stability is also excellent.

When mixing the aqueous dispersion of resin particles obtained in Step 2 and the aqueous dispersion of amorphous polyester particles, the amorphous polyester used is the same as the amorphous polyester used for the core portion. But it can be different.
The amount of the amorphous polyester is preferably 10 to 300 parts by weight, more preferably 20 to 100 parts by weight, based on 100 parts by weight of the crystalline polyester of the resin particles. Moreover, 5-100 weight part is preferable with respect to 100 weight part of amorphous polyester of a resin particle, and 10-80 weight part is preferable.
The average particle size of the resin particles A obtained by mixing the resin particles and the aqueous dispersion of amorphous polyester particles is preferably 1 to 10 μm in terms of volume median particle size from the viewpoint of uniform aggregation. -8 μm is more preferable, and 3-7 μm is more preferable.
The aggregation conditions for the resin particles are the same as in Step 2, and the coalescence conditions are the same as in Step 3.
The preferred weight ratio between the crystalline polyester and the amorphous polyester in the core-shell particles is also as described above.

(Manufacture of toner)
The toner of the present invention can be obtained by subjecting the coalesced resin particles obtained in the above step to a solid-liquid separation step such as filtration, a washing step, and a drying step as appropriate.
In the washing step, it is preferable to use an acid in order to remove metal ions on the toner surface in order to ensure sufficient charging characteristics and reliability as the toner. Further, it is preferable to completely remove the added nonionic surfactant by washing, and washing with an aqueous solution below the cloud point of the nonionic surfactant is preferred. The washing is preferably performed a plurality of times.
In the drying step, any method such as a vibration type fluidized drying method, a spray drying method, a freeze drying method, a flash jet method, or the like can be employed. The water content after drying of the toner is preferably adjusted to 1.5% by weight or less, more preferably 1.0% by weight or less, from the viewpoint of chargeability.

From the viewpoint of high image quality and productivity, the volume median particle size of the toner is preferably 1 to 10 μm, more preferably 2 to 8 μm, and even more preferably 3 to 7 μm.
Further, the softening point of the toner is preferably 80 to 160 ° C., more preferably 80 to 150 ° C., and further preferably 90 to 140 ° C. from the viewpoint of low-temperature fixability. Moreover, 45-80 degreeC is preferable from the same viewpoint, and, as for glass transition temperature, 50-70 degreeC is more preferable.

An auxiliary agent such as a fluidizing agent may be added to the toner particle surface as an external additive to the toner obtained by the present invention. Examples of the external additive include silica fine particles whose surface is hydrophobized, titanium oxide fine particles, alumina fine particles, cerium oxide fine particles, and inorganic fine particles such as carbon black; polymer fine particles such as polycarbonate, polymethyl methacrylate, and silicone resin, and the like. Fine particles can be used.
The number average particle diameter of the external additive is preferably 4 to 200 nm, more preferably 8 to 30 nm. The number average particle diameter of the external additive is determined using a scanning electron microscope or a transmission electron microscope.

The amount of the external additive is preferably 0.8 to 5.0 parts by weight, more preferably 1.0 to 5.0 parts by weight, with respect to 100 parts by weight of the toner before processing with the external additive. 5 to 3.5 parts by weight are more preferable. However, when hydrophobic silica is used as an external additive, 0.8 to 3.5 parts by weight, preferably 1.0 to 3 parts by weight of hydrophobic silica is used with respect to 100 parts by weight of toner before processing with the external additive. By using 0.0 part by weight, the desired effect can be obtained.
The toner of the present invention can be used as a one-component developer or as a two-component developer mixed with a carrier.

[Measurement of particles in polyester and dispersion]
The measurement of the softening point, glass transition temperature, melting point, acid value, weight average molecular weight, and volume median particle size (D ₅₀ ) of the polyester obtained in each example was performed as follows.
(Softening point)
Using a flow tester (manufactured by Shimadzu Corporation, CFT-500D), a 1 g sample was heated at a heating rate of 6 ° C./min while a load of 1.96 MPa was applied by a plunger, and the diameter was 1 mm and the length was 1 mm. Extruded from the nozzle. The amount of plunger drop of the flow tester was plotted against the temperature, and the temperature at which half of the sample flowed out was taken as the softening point.
(Glass-transition temperature)
Using a differential scanning calorimeter (manufactured by TA Instruments Japan Co., Ltd., Q-100), 0.01 to 0.02 g of the sample was weighed into an aluminum pan, heated to 200 ° C., and the temperature The sample cooled to 0 ° C at a temperature drop rate of 10 ° C / min is heated at a rate of temperature rise of 10 ° C / min, extending from the baseline extension line below the endothermic peak temperature and from the peak rise to the peak apex. The temperature at the intersection with the tangent showing the maximum inclination was defined as the glass transition temperature.

(Maximum endothermic peak temperature, melting point)
Using a differential scanning calorimeter (manufactured by TA Instruments Japan Co., Ltd., Q-100), the sample cooled from room temperature to 0 ° C. at a temperature lowering rate of 10 ° C./min is left still for 1 minute, and then the temperature is raised. Measure up to 150 ° C at a rate of 10 ° C / min. Among the observed endothermic peaks, the temperature of the peak at the highest temperature side was defined as the maximum endothermic peak temperature, and the melting point if the maximum peak temperature was within 20 ° C. from the softening point.
(Acid value)
Measured according to the method of JIS K 0070. However, only the measurement solvent is changed from the mixed solvent of ethanol and ether specified in JIS K 0070 to a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

(Weight average molecular weight)
(1) Preparation of sample solution Polyester is dissolved in THF so that the concentration is 0.04 g / 10 ml. Subsequently, this solution was filtered using a fluororesin filter having a mesh of 0.45 μm [manufactured by Advantech Co., Ltd., “DISMIC-25JP”] to remove insoluble components to obtain a sample solution.
(2) Molecular weight measurement Using the following apparatus, THF was flowed at a flow rate of 1 ml / min, and the column was stabilized in a constant temperature bath at 40 ° C. Measurement was performed by injecting 100 μl of the sample solution. The molecular weight of the sample was calculated based on a calibration curve prepared in advance. For the calibration curve at this time, several types of monodisperse polystyrene prepared as standard samples were used.
Measuring device: HLC-8220 GPC (manufactured by Tosoh Corporation)
Analytical column: GMH _XL + G3000H _XL (manufactured by Tosoh Corporation)
(Volume median particle size (D ₅₀ ))
Using a laser diffraction type particle size analyzer (SALD-2000J, manufactured by Shimadzu Corporation), add distilled water to the measurement cell and measure the volume median particle size (D ₅₀ ) at a concentration where the absorbance is in the proper range. To do.

[Production of crystalline polyester (resins A to C)]
1,6-Hexanediol and terephthalic acid shown in Table 1 and 40 g of tin octylate were charged into a 10 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple at 180 ° C. After reacting for 4 hours, the temperature was raised to 210 ° C. at 10 ° C./1 hour and held at 210 ° C. for 8 hours. Thereafter, the temperature was lowered to 200 ° C., the remaining acid was added, and the mixture was further reacted for 4 hours, and further reacted at 8.3 kPa for 1 hour.
Table 1 shows the physical properties of the obtained resin. In Table 1, the values in () are molar ratios (mol%) when the number of moles of the alcohol component is 100.

[Production Example of Amorphous Polyester (Resin AA, AB)]
Raw materials other than trimellitic anhydride shown in Table 2 and 40 g of tin octylate were charged into a 10 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, and at 230 ° C. for 8 hours. After the reaction, the reaction was carried out at 8.3 kPa for 1 hour. Further, trimellitic anhydride was added at 210 ° C. until the softening point was reached.
Table 2 shows the physical properties of the obtained resin. In Table 2, the values in () are molar ratios (mol%) when the number of moles of the alcohol component is 100.

[Production example of melt-mixed polyester (resins BA to BD)]
In a 10 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, as shown in Table 3, the amorphous polyester resin AA, Add 3.5 kg of AB, melt and stir at 180 ° C., add 1.5 kg of crystalline polyester resins A to C obtained in the above examples and comparative examples, stir for 30 minutes and cool to obtain a melt-mixed resin It was.

[Production example of dispersion]
(Polyester dispersions A to C, AA, AB)
600 g of methyl ethyl ketone is put into a 5 L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer and nitrogen introduction tube, and 200 g of each of the polyester resins A to C, AA and AB obtained above is heated to 60 ° C. Added and dissolved. 10 g of triethylamine was added to the resulting solution for neutralization, and then 2000 g of ion-exchanged water was added, and then methyl ethyl ketone was distilled off at a temperature of 50 ° C. or lower under reduced pressure at a stirring speed of 250 r / min. A self-dispersing aqueous resin particle dispersion (resin content: 9.6% by weight (in terms of solid content)) was obtained. The volume-average particle size of the polyester particles dispersed in the obtained resin dispersion was 0.3 μm.

(Mixed polyester dispersions BA to BD (melt mixing))
Instead of the polyester resins A to C, AA and AB, the same procedure as for the aqueous dispersion containing the polyester resin was performed except that the melt mixed resins BA to BD obtained in the production examples of the melt mixed resin were used. A self-dispersing aqueous resin particle dispersion containing a mixed resin (resin content: 9.6% by weight (in terms of solid content)) was obtained. The volume-average particle size of the polyester particles dispersed in the obtained resin dispersion was 0.3 μm.

(Mixed polyester dispersion CA (resin B + resin AB))
Into a 5 L container equipped with a stirrer, reflux condenser, dropping funnel, thermometer and nitrogen introduction tube, 600 g of methyl ethyl ketone is charged, and 60 g of crystalline polyester resin B and 140 g of amorphous polyester resin AB are added and dissolved at 60 ° C. It was. 10 g of triethylamine was added to the resulting solution for neutralization, and then 2000 g of ion-exchanged water was added, and then methyl ethyl ketone was distilled off at a temperature of 50 ° C. or lower under reduced pressure at a stirring speed of 250 r / min. A self-dispersing aqueous resin particle dispersion (resin content: 9.6% by weight (in terms of solid content)) was obtained. The volume-average particle size of the polyester particles dispersed in the obtained resin dispersion was 0.3 μm.

(Other dispersions)
<Colorant dispersion>
Copper phthalocyanine (Daiichi Seika Kogyo Co., Ltd., Model: ECB-301) 50 g Nonionic surfactant (Kao Co., Ltd., Emulgen 150) 5 g and ion-exchanged water 200 g are mixed to dissolve copper phthalocyanine, and homogenizer Was used for 10 minutes to obtain a dispersed colorant dispersion. The volume median particle size was 120 nm.
<Wax dispersion>
Paraffin wax (Nippon Seiwa Co., Ltd., HNP0190, melting point: 85 ° C.) 50 g, cationic surfactant (Kao Corporation, Sanizol B50) 5 g and ion-exchanged water 200 g are heated to 95 ° C. and a homogenizer is used. Then, after the paraffin wax was dispersed, it was dispersed with a pressure discharge type homogenizer to obtain a wax dispersion. The volume median particle size of the paraffin wax was 550 nm.

[Measurement and evaluation of toner]
Measurement of the volume median particle size (D ₅₀ ) and evaluation of transparency of the toners obtained in Examples and Comparative Examples were performed as follows. The measurement of the melting point and glass transition temperature of the toner is the same as the measurement of the polyester resin.
(Volume-median particle diameter of toner (D ₅₀ ))
(1) Preparation of dispersion: 10 mg of a measurement sample was added to 5 ml of dispersion [“Emulgen 109P” (manufactured by Kao Corporation, polyoxyethylene lauryl ether, HLB: 13.6) 5 wt% aqueous solution], and ultrasonic dispersion was performed. Then, 25 ml of electrolyte [“ISOTON II” (manufactured by Beckman Coulter, Inc.)] is added and further dispersed for 1 minute with an ultrasonic disperser to obtain a dispersion.
(2) Measuring device: “Coulter Multisizer II” (Beckman Coulter, Inc.)
Aperture diameter: 50 μm
Analysis software: “Coulter Multisizer AccuComp version 1.19” (Beckman Coulter, Inc.)
(3) Measurement conditions: 100 ml of electrolyte solution and dispersion were added to a beaker, and the volume median particle size (D ₅₀ ) of 30,000 particles at a concentration at which the particle size of 30,000 particles could be measured in 20 seconds. Ask for.

(transparency)
(1) Mount the toner on the printer (manufactured by Oki Data Corporation, ML5400), adjust the developing bias so that the unfixed toner adhesion amount on the paper surface is 0.60 ± 0.05 mg / cm ² , An unfixed solid image was output.
The fixing machine of the above printer is fixed to paper at 60 mm / sec while increasing the fixing temperature from 90 ° C. to 200 ° C. in increments of 5 ° C., and “UNICEF Cellophane” (Mitsubishi Pencil Co., Ltd. : 18 mm, JIS Z 1522) was pasted and 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 (Macbeth RD-915), and the ratio between the two (after peeling / before sticking) first exceeds 90%. Was set as the minimum fixing temperature. The solid image printed at the minimum fixing temperature was subjected to the following processing, and the transparency was measured.
(2) A4-sized OHP sheet (manufactured by Nakabayashi Co., Ltd., OHP film, for double-sided dry copy LBP) was used as the paper. The obtained solid image was cut into 4 cm × 5 cm, and the transparency was measured using a spectral color difference meter (manufactured by Nippon Denshoku Industries Co., Ltd., SE2000).
The transparency was measured by cutting an unprinted OHP sheet in advance to 4 cm × 5 cm, fixing it to a jig with a measurement area of 30 mmΦ, and measuring the background, and then measuring the transparency of the OHP sheet on which a solid image was printed by the same method. At this time, the measurement was performed by installing the solid image so that the irradiated light was applied from the back side of the printing surface. The measurement conditions were 380 to 780 nm, and the wavelength output interval was measured every 10 nm. Transparency (%) at 480 nm was defined as cyan transparency, and the transparency was evaluated according to the following evaluation criteria.

A: 95% or more B: 80 to less than 95 C: less than 70 to 80 D: less than 60 to 70 E: less than 50 to 60 F: less than 50%

[Examples 1 to 5, Comparative Example 1]
(1) Polyester dispersions shown in Table 4 obtained by the above-described production examples of dispersions (Example 5 uses crystalline polyester dispersion and amorphous polyester dispersion as shown in Table 4). 500 g, 20 g of a colorant dispersion, 15 g of a wax dispersion, and 1.5 g of a cationic surfactant (manufactured by Kao Corporation, Sanisol B50) are mixed and dispersed in a round stainless steel flask using a homogenizer. Then, it heated to 48 degreeC, stirring the inside of a flask in the oil bath for heating. Furthermore, after maintaining at 48 ° C. for 1 hour, it was confirmed that aggregated particles having a weight average particle diameter of 5.1 μm were formed.
(2) After adding 3 g of an anionic surfactant (PEX SS-L, manufactured by Kao Corporation) to the aggregated particle dispersion in which the aggregated particles are formed, a reflux tube is attached to the stainless steel flask, and stirring is performed. While continuing, it was heated to 80 ° C. at a rate of 0.1 ° C./min and held for 5 hours to coalesce and fuse the aggregated particles. Thereafter, the mixture was cooled to room temperature, the fused particles were filtered, sufficiently washed with ion exchange water, and then dried to obtain colored resin fine particle powder. The obtained colored resin fine particle powder had a volume median particle size (D ₅₀ ) of 5.0 μm.
(3) Next, 0.2 parts by weight of hydrophobic silica (TS530, manufactured by Wacker Chemie, number average particle size: 8 nm) is added to 100 parts by weight of the obtained colored resin fine particle powder, and a Henschel mixer is used. The toner was mixed and externally added to obtain a cyan toner. The resulting cyan toner had a volume-median particle size (D ₅₀ ) of 5.0 μm.
The melting point and glass transition temperature of the obtained cyan toner were measured, and the evaluation of transparency is shown in Table 4.

[Example 6, Comparative Example 2]
100 parts by weight of polyester resin shown in Table 5 (total weight 5 kg), 4 parts by weight of cyan pigment (manufactured by Dainichi Seika Kogyo Co., Ltd., ECB-301) obtained by the production of the above crystalline and amorphous polyesters, polyethylene After fully mixing 1 part by weight of wax (manufactured by Nippon Seiki Co., Ltd., HNP-9, melting point 80 ° C.) with a Henschel mixer, the kneading part has a total length of 1560 mm, a screw diameter of 42 mm and a barrel inner diameter of 43 mm. Was used for melt kneading at a roll rotation speed of 200 r / min and a heating temperature in the roll of 90 ° C. The feed rate of the mixture was 20 kg / hr, and the average residence time was about 18 seconds. The obtained melt-kneaded product was cooled and coarsely pulverized, then pulverized by a jet mill and classified to obtain a powder having a volume median particle size (D ₅₀ ) of 5.0 μm.
Cyan toner is obtained by adding 1.0 part by weight of hydrophobic silica (Aerosil R-972, manufactured by Nippon Aerosil Co., Ltd.) as an external additive to 100 parts by weight of the obtained powder and mixing with a Henschel mixer. It was. The resulting cyan toner had a volume-median particle size (D ₅₀ ) of 5.0 μm.
The melting point and glass transition temperature of the obtained cyan toner were measured, and the evaluation of transparency is shown in Table 5.

[Example 7] (Toner containing core-shell particles)
The melt-mixed polyester dispersion BB = 500 g, the colorant dispersion 20 g, the wax dispersion 15 g, the charge control agent dispersion 7 g, and the cationic surfactant (manufactured by Kao Corporation, Sanisol B50) obtained by the production of the above dispersion. ) 1.5 g was mixed and dispersed in a round stainless steel flask using a homogenizer, and then heated to 48 ° C. while stirring the inside of the flask in an oil bath for heating. Furthermore, after maintaining at 48 ° C. for 1 hour, it was confirmed that aggregated particles having a weight average particle diameter of 5.1 μm were formed. Thereafter, 50 g of polyester dispersion AB was added to obtain aggregated particles which were encapsulated core-shell particles.
After adding 3 g of an anionic surfactant (PEX SS-L, manufactured by Kao Corporation) to the aggregated particle dispersion in which core-shell aggregated particles are formed, a reflux tube is attached to the stainless steel flask, and stirring is continued. While heating to 80 ° C. at a rate of 0.1 ° C./min and holding for 5 hours, the aggregated particles were coalesced and fused. Thereafter, the mixture was cooled, the fused particles were filtered, washed thoroughly with ion exchange water, and then dried to obtain colored resin fine particle powder. The obtained colored resin fine particle powder had a volume median particle size (D ₅₀ ) of 5.0 μm.
Next, the obtained colored resin fine particle powder was used in the same manner as in Example 3 to obtain a cyan toner. The resulting cyan toner had a volume-median particle size (D ₅₀ ) of 5.0 μm.
The melting point and glass transition temperature of the obtained cyan toner were measured, and the evaluation of transparency is shown in Table 6.

[Production example of polyester dispersion]
(Polyester dispersion A ')
5 g of polyester resin A 200 g obtained in Example 1 and 100 g of nonionic surfactant [polyoxyethylene lauryl ether (EO = 9 mol addition), cloud point: 98 ° C., HLB: 15.3] Was melted at 140 ° C. with stirring at 200 r / min with a chi-type stirrer. The content was stabilized at 95 ° C., which is 3 ° C. lower than the cloud point of the nonionic surfactant, and a sodium hydroxide aqueous solution (concentration: 5% by weight) 75 as a neutralizing agent under stirring at 200 r / min with a chi-type stirrer. 0.5 g was added dropwise. Subsequently, deionized water was added dropwise at 6 g / min with stirring at 300 r / min with a Kai-type stirrer, and a total of 1624.5 g was added. During this time, the system temperature was maintained at 95 ° C., and a polyester dispersion A ′ was obtained through a 200 mesh (mesh opening: 105 μm) wire mesh.
The polyester particles (primary particles) in the obtained polyester dispersion had a volume median particle size (D ₅₀ ) of 0.35 μm and a solid concentration of 12.0% by weight. No resin component remained on the wire mesh.

(Polyester dispersion AA ')
A polyester dispersion AA ′ was obtained in the same manner as the polyester dispersion A ′ using the amorphous polyester AA obtained in the polyester production example.
The polyester particles (primary particles) in the obtained polyester dispersion had a volume median particle size (D ₅₀ ) of 0.35 μm and a solid concentration of 12.0% by weight. No resin component remained on the wire mesh.

[Example 8]
The polyester dispersion A ′ / AA ′ = 60/140 g, which was obtained by the production of the above dispersion, was prepared at a ratio of 8 g of colorant dispersion, 6 g of wax dispersion, 2 g of charge control agent dispersion, and deionized. Then, 52 g of water was put in a 2 L container, and then 146 g of a 6.2 wt% aqueous ammonium sulfate solution was added dropwise at room temperature with stirring at 100 r / min with a chi-type stirrer over 30 minutes. Then, it heated up, stirring, when it became 50 degreeC, it fixed to 50 degreeC and hold | maintained for 3 hours. After forming aggregated particles by this, a dilute solution obtained by diluting 4.2 g of polyoxyethylene dodecyl ether sodium sulfate aqueous solution (solid content 28 wt%) with 37 g of deionized water was added. The temperature was raised to 80 ° C. at 0.16 ° C./min. After the temperature reached 80 ° C. and maintained at 80 ° C. for 1 hour, heating was terminated. The mixture was gradually cooled to room temperature, and toner mother particles were obtained through a suction filtration step, a washing step, and a drying step.
To 100 parts by weight of the toner base particles, 2.0 parts by weight of hydrophobic silica (manufactured by Nippon Aerosil Co., Ltd., R972, number average particle diameter 16 nm) was externally added using a Henschel mixer to obtain a cyan toner. The obtained toner had a volume-median particle size (D ₅₀ ) of 4.7 μm.
The melting point and glass transition temperature of the obtained cyan toner were measured, and the evaluation of transparency is shown in Table 7.

  Since the electrophotographic toner of the present invention is excellent in transparency, it can be suitably used for developing a latent image formed in electrophotography, electrostatic recording method, electrostatic printing method and the like.

Claims (7)

  For toner obtained by condensation polymerization of an alcohol component containing an aliphatic diol having 2 to 8 carbon atoms and a carboxylic acid component containing at least one selected from aromatic dicarboxylic acid and alkyl succinic acid and alkenyl succinic acid Crystalline polyester.   The crystalline polyester for toner according to claim 1, wherein the total content of alkyl succinic acid and alkenyl succinic acid in the carboxylic acid component is 1 to 30 mol%.   The crystalline polyester for toner according to claim 1, wherein the alcohol component contains α, ω-linear alkanediol.   An electrophotographic toner comprising, as a binder resin, a polyester containing the crystalline polyester according to any one of claims 1 to 3 and an amorphous polyester.   The electrophotographic toner according to claim 4, which is obtained by aggregating and coalescing the aqueous dispersion containing the crystalline polyester according to claim 1 and the aqueous dispersion containing the amorphous polyester.   The electrophotographic toner according to claim 4, which is obtained by aggregating and coalescing an aqueous dispersion of a mixed polyester containing the crystalline polyester according to claim 1 and an amorphous polyester.   The electrophotography according to any one of claims 4 to 6, wherein the amorphous polyester comprises a polyester component obtained by polycondensation of a carboxylic acid component containing at least one selected from alkyl succinic acid and alkenyl succinic acid and an alcohol component. Toner.