JP2021107895A - Binder resin for toners - Google Patents

Abstract

To provide a binder resin for toners having excellent storage properties and durability.SOLUTION: A binder resin for toners contains a composite resin in which a vinyl resin unit and a polyester resin unit are bonded to each other via a covalent bond. The composite resin is a resin obtained by polycondensing, in the presence of a vinyl resin (A) constituting the vinyl resin unit, a raw material monomer (b) constituting the polyester resin unit. The vinyl resin (A) is a resin obtained by solution-polymerizing a raw material monomer (a) comprising a bireactive monomer in a solvent with a boiling point of 60°C or higher and 180°C or lower at monomer concentration of 27 mass% or greater.SELECTED DRAWING: None

Description

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

In the field of electrophotographic, with the development of electrophotographic systems, the development of toner for static charge image development corresponding to high image quality and high-speed printing is required.
In response to such demands, styrene acrylic resin and polyester resin having excellent low-temperature fixability are used as the binder resin for toner, and in order to satisfy multiple performances at the same time, consideration is given to compounding multiple resins. Has been done.

In Patent Document 1, the binder resin of the toner particles is used as a low softening point resin by addition-polymerizing a vinyl-based monomer in the presence of a shrink-polymerized monomer, and after the addition polymerization reaction is completed, the shrink-polymerized monomer is shrunk. In the presence of a resin obtained by polymerization or a vinyl resin obtained by addition-polymerizing a vinyl-based monomer, a resin obtained by shrink-polymerizing a shrink-polymerized monomer and a highly softened point resin are shrink-polymerized. The shrink-polymerized resin obtained by shrink-polymerizing the system monomer contains a resin obtained by adding, mixing and addition-polymerizing the vinyl-based monomer, and the softening point of the low softening point resin is the high softening point. A toner having a mass ratio of 5 ° C. or more lower than the softening point of the resin and a mass ratio of the low softening point resin to the high softening point resin is described, and is excellent in low temperature fixability, high temperature offset resistance and developability. It is stated that toner can be obtained.
Patent Document 2 describes a polyester resin having a hydroxyl value of 30 to 60 and an acid value of 5 or less, and a styrene having an acid value of 1 to 10 and a molecular weight of 5,000 to 500,000. A binder for an electrophotographic toner containing a block polymer obtained by esterifying a based resin is described, and it is described that a toner having good fixing performance and excellent image stability can be obtained.

Japanese Unexamined Patent Publication No. 2008-102396 Japanese Unexamined Patent Publication No. 2-881

If the softening point and the glass transition temperature of the toner are designed to be low in order to improve the low temperature fixability of the toner, there is an adverse effect that the durability is lowered. Therefore, in order to improve the durability, an attempt has been made to impart releasability by dispersing wax in the toner. However, if the dispersibility of the wax in the toner is low, there is a problem that the storage stability and durability are lowered.
In the technique of Patent Document 1, since the monomer concentration at the time of solution polymerization of the vinyl resin is low, it is difficult to control the molecular weight distribution of the vinyl resin and the copolymerizability of the monomer, and the dispersion stability of the wax in the toner is improved. It turned out not enough.
Further, in the technique of Patent Document 2, the polyester resin is added to the polymerization reaction solution of the styrene resin in the absence of the bireactive monomer, and then the solvent is removed to esterify the styrene resin. The unit and the polyester-based unit are not uniformly dispersed, and the dispersion stability of the wax is insufficient.
Therefore, it is required to improve the dispersion stability of the wax in the toner and improve the storage stability and durability.
The present invention relates to a toner binder resin having excellent storage stability and durability, a static charge developing toner, and a method for producing a toner binder resin.

As the composite resin contained in the binder resin for toner, the present inventors use a resin obtained by polycondensing the raw material monomers constituting the polyester resin unit in the presence of the vinyl resin constituting the vinyl resin unit. By using the vinyl-based resin as a resin obtained by solution-polymerizing a raw material monomer containing both reactive monomers at a predetermined monomer concentration in a solvent having a boiling point in a predetermined range, storage stability and durability can be achieved. We found that the problem could be solved.

That is, the present invention relates to the following embodiments [1] to [3].
[1] A binder resin for toner containing a composite resin in which a vinyl-based resin unit and a polyester-based resin unit are bonded via a covalent bond.
The composite resin is a resin obtained by polycondensing the raw material monomer (b) constituting the polyester resin unit in the presence of the vinyl resin (A) constituting the vinyl resin unit.
The vinyl resin (A) is a resin obtained by solution-polymerizing a raw material monomer (a) containing both reactive monomers in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more. There is a binder resin for toner.
[2] A toner for developing an electrostatic charge image, which contains the binder resin for toner according to the above [1].
[3] A method for producing a binder resin for toner, which contains a composite resin in which a vinyl resin unit and a polyester resin unit are bonded via a covalent bond.
Step I: A vinyl-based resin unit is formed by solution-polymerizing a raw material monomer (a) containing both reactive monomers in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more. Steps of obtaining the resin (A) and Step II: In the presence of the vinyl-based resin (A) obtained in Step I, the raw material monomers (b) constituting the polyester-based resin unit are polycondensed to form the composite resin. The process of forming and obtaining a binder resin for toner,
A method for producing a binder resin for toner, including.

According to the present invention, it is possible to provide a binder resin for toner, a toner for developing an electrostatic charge image, and a method for producing a binder resin for toner, which are excellent in storage stability and durability.

[Bundling resin for toner]
The binder resin for toner of the present invention (hereinafter, also simply referred to as “the binding resin of the present invention”) is a composite resin in which a vinyl resin unit and a polyester resin unit are bonded via a covalent bond. It is a binder resin for toner contained.
The composite resin is a resin obtained by polycondensing the raw material monomer (b) constituting the polyester resin unit in the presence of the vinyl resin (A) constituting the vinyl resin unit.
Further, the vinyl resin (A) is obtained by solution-polymerizing the raw material monomer (a) containing both reactive monomers in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more. It is a resin.
According to the toner of the present invention, excellent storage stability and durability are exhibited.
In the present invention, "solution polymerization" means polymerization in which a raw material monomer is dissolved in a solvent and polymerized in a solution system, and the resulting polymer may be dissolved in the solvent or not dissolved in the solvent. May be precipitated in.

The reason why the effect of the present invention can be obtained is not clear, but it is considered as follows.
The vinyl-based resin unit of the composite resin contained in the binder resin of the present invention is a solvent having a boiling point within a predetermined range in the absence of the polyester-based resin constituting the polyester-based resin unit and the raw material monomer constituting the resin. Among them, it is composed of a vinyl-based resin obtained by solution-polymerizing a raw material monomer containing both reactive monomers at a predetermined monomer concentration. Therefore, the polymerization field of the raw material monomer of the vinyl resin is not a polyester resin or a polycondensation monomer as in the conventional case, but a solvent having a boiling point in a predetermined range, and the monomer concentration is in a predetermined range, so that it remains. It is possible to form a more uniform vinyl-based resin unit in which the amount of monomers is small and the molecular weight distribution and the copolymerizability of the monomers are controlled, and the compatibility between the vinyl-based resin unit and the wax can be easily controlled. As a result, it is considered that the dispersion stability of the wax in the toner is improved, the wax is less likely to be unevenly distributed in the toner or unevenly distributed on the toner surface, and the storage stability and durability are improved.

Definitions of various terms in the present specification are shown below.
The "polyester resin" may include a polyester resin modified to such an extent that its characteristics are not substantially impaired. Examples of the modified polyester resin include a urethane-modified polyester resin in which the polyester resin is modified by a urethane bond, and an epoxy-modified polyester resin in which the polyester resin is modified by an epoxy bond.
"Bisphenol A" means 2,2-bis (4-hydroxyphenyl) propane.
Examples of the "carboxylic acid compound" include carboxylic acids, their anhydrides, and alkyl esters having 1 or more and 3 or less carbon atoms. The carbon number of the alkyl group of the alkyl ester is not included in the carbon number of the carboxylic acid compound.
The "binding resin" means a resin component containing a composite resin in the toner.

The toner of the present invention contains a colorant and a binder resin.
The toner of the present invention contains, for example, toner particles and an external additive.
The toner particles preferably contain a colorant and a binder resin.
The toner particles may contain, for example, a mold release agent, a colorant derivative, a charge control agent, and other additives.

<Composite resin>
The composite resin is a resin in which a vinyl-based resin unit and a polyester-based resin unit are bonded via a covalent bond.
The composite resin is a vinyl-based resin obtained by solution-polymerizing a raw material monomer (a) containing both reactive monomers in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more. In the presence of A), the resin is obtained by polycondensing the raw material monomer (b) constituting the polyester resin unit.
The mass ratio of the vinyl-based resin unit to the polyester-based resin unit in the composite resin [vinyl-based resin unit / polyester-based resin unit] uniformly disperses the vinyl-based resin unit and improves the dispersion stability of the wax in the toner. From the viewpoint, it is preferably 3/97 to 70/30, more preferably 6/94 to 60/40, still more preferably 9/91 to 50/50, still more preferably 12/88 to 40/60, still more preferably 15/ It is 85 to 30/70.

[Vinyl resin unit]
(Raw material monomer (a))
The vinyl-based resin unit is an addition polymer of the raw material monomer (a), which is composed of the vinyl-based resin (A) and contains both reactive monomers, from the viewpoint of improving the storage stability and durability.
The raw material monomer (a) further preferably further contains a (meth) acrylic acid ester, and more preferably further contains a (meth) acrylic acid ester and a styrene compound.

Examples of the (meth) acrylic acid ester include methyl (meth) acrylic acid, ethyl (meth) acrylic acid, n-propyl (meth) acrylic acid, isopropyl (meth) acrylic acid, n-butyl (meth) acrylic acid, and (meth). ) Isobutyl acrylate, tert-butyl (meth) acrylate, amyl (meth) acrylate, cyclohexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, decyl (meth) acrylate , (Meta) lauryl acrylate, (meth) 2-ethylhexyl acrylate, stearyl (meth) acrylate, methoxyethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate, ( Examples thereof include 2-chloroethyl (meth) acrylate, phenyl (meth) acrylate, 2- (dimethylamino) ethyl (meth) acrylate, 2- (diethylamino) ethyl (meth) acrylate, and methyl α-chloroacrylate. ..
In addition, "(meth) acrylic acid ester" indicates that the case of both acrylic acid ester and methacrylic acid ester is included.

The (meth) acrylic acid ester is preferably a (meth) acrylic acid ester having a hydrocarbon group from the viewpoint of improving storage stability and durability.
The hydrocarbon group of the (meth) acrylic acid ester preferably has 4 or more carbon atoms, more preferably 6 or more carbon atoms, still more preferably 8 or more carbon atoms, and preferably 22 or less, more preferably 20 or less, still more preferably 18. It is as follows. The carbon number of the hydrocarbon group of the (meth) acrylic acid ester means the number of carbon atoms derived from the alcohol component constituting the ester.

The (meth) acrylic acid ester is preferably a (meth) acrylic acid ester having an alkyl group having 4 or more carbon atoms from the viewpoint of improving storage stability and durability, and is preferably butyl acrylate, 2-ethylhexyl acrylate, and lauryl methacrylate. , And at least one selected from stearyl methacrylate is more preferred, and at least one selected from 2-ethylhexyl acrylate, lauryl methacrylate, and stearyl methacrylate is even more preferred.

Examples of the styrene compound include styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-chlorostyrene, vinylnaphthalene and the like. Examples thereof include styrene and styrene derivatives, preferably styrene and α-methylstyrene.

The raw material monomer (a) may further contain a vinyl-based monomer other than the styrene compound and the (meth) acrylic acid ester.
Examples of other vinyl-based monomers include ethylenically unsaturated monoolefins such as ethylene, propylene, butylene and isobutylene; diolefins such as butadiene; halovinyls such as vinyl chloride, vinyl bromide and vinyl fluoride; acetic acid. Vinyl esters such as vinyl, vinyl propionate, vinyl formate, vinyl caproate; ethylenic monocarboxylic acids such as acrylic acid and methacrylic acid; vinyl ethers such as vinyl methyl ether, vinylidene halides such as vinylidene chloride; N-vinyl Examples thereof include N-vinyl compounds such as pyrrole and N-vinylpyrrolidone.

The content of the (meth) acrylic acid ester in the total amount of the monomers other than the bireactive monomer contained in the raw material monomer (a) is preferably 5% by mass or more, more preferably 5% by mass or more from the viewpoint of improving storage stability and durability. It is 10% by mass or more, more preferably 15% by mass or more, still more preferably 20% by mass or more, and preferably 50% by mass or less, more preferably 45% by mass or less, still more preferably 40% by mass or less, still more preferably. Is 35% by mass or less.
The content of the styrene compound in the total amount of the monomers other than the bireactive monomer contained in the raw material monomer (a) is preferably 50% by mass or more, more preferably 55% by mass or more from the viewpoint of improving storage stability and durability. , More preferably 60% by mass or more, still more preferably 65% by mass or more, and preferably 95% by mass or less, more preferably 90% by mass or less, still more preferably 85% by mass or less, still more preferably 80% by mass. It is as follows.

The total content of the (meth) acrylic acid ester and the styrene compound in the total amount of the monomers other than the bireactive monomer contained in the raw material monomer (a) is preferably 90% by mass from the viewpoint of improving storage stability and durability. As mentioned above, it is more preferably 95% by mass or more, further preferably 99% by mass or more, still more preferably 100% by mass.

(Bi-reactive monomer)
The bireactive monomer copolymerizes with a monomer other than the bireactive monomer contained in the raw material monomer (a) at the time of polymerization of the raw material monomer (a), and forms a polyester resin unit (b). Can react with.
As a result, the composite resin has a structure in which a vinyl-based resin resin unit containing a structural unit derived from both reactive monomers and a polyester-based resin unit are bonded via a structural unit derived from the bireactive monomer, and vinyl is formed. The binder resin in which the based resin unit and the polyester based resin unit are uniformly dispersed can be obtained, the dispersibility of the wax is improved, and the storage stability and durability are improved.
The bireactive monomer preferably has an ethylenically unsaturated bond and one or more functional groups selected from a carboxy group, a hydroxyl group, an epoxy group, a primary amino group and a secondary amino group in the molecule. A compound having an ethylenically unsaturated bond and one or more functional groups selected from a carboxy group and a hydroxyl group, more preferably an ethylenically unsaturated bond and a carboxy, from the viewpoint of reactivity. It is a compound having a group.

Specific examples of the bireactive monomer include acrylic acid, methacrylic acid, fumaric acid, maleic acid, and maleic anhydride. Among them, acrylic acid, from the viewpoint of reactivity with a monomer other than the bireactive monomer contained in the raw material monomer (a) and reactivity with the raw material monomer (b) after being introduced into the vinyl resin (A). Methacrylic acid and fumaric acid are preferable, acrylic acid and methacrylic acid are more preferable, and acrylic acid is further preferable.
The amount of the bireactive monomer is preferably 0.5 part by mass with respect to 100 parts by mass of the total amount of the monomers other than the bireactive monomer contained in the raw material monomer (a) from the viewpoint of improving the storage stability and durability. The above is more preferably 1 part by mass or more, further preferably 2 parts by mass or more, further preferably 3 parts by mass or more, still more preferably 4 parts by mass or more, and preferably 10 parts by mass or less, more preferably 8 parts by mass. Parts or less, more preferably 6 parts by mass or less.

(Manufacturing of resin (A))
The vinyl resin (A) is obtained by a solution polymerization method including the following step I from the viewpoint of controlling the molecular weight distribution and the copolymerizability of the monomer.
Step I: A step of solution-polymerizing a raw material monomer (a) containing a bireactive monomer in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more to obtain a vinyl resin (A).

In step I, the solution polymerization of the raw material monomer (a) is independent of the polymerization system of the monomer (b) constituting the polyester resin unit from the viewpoint of facilitating the control of the molecular weight distribution and the copolymerizability of the monomer. It is carried out by the reaction system. That is, the solution polymerization of the step I is performed in the absence of the raw material monomer (b) constituting the polyester resin unit and the polycondensate of the raw material monomer (b).

In the present invention, the solution polymerization of the raw material monomer (a) is carried out in a state where the raw material monomer (a) is dissolved in a solvent. From this point of view, the solvent dissolves the raw material monomer (a), and preferably dissolves both the raw material monomer (a) and the obtained vinyl resin (A).
In the present invention, "the raw material monomer (a) dissolves in a solvent" means that when the raw material monomer (a) and the solvent are mixed and allowed to stand, they do not separate into multiple phases.
That is, in step I of the present invention, the type of solvent and the monomer concentration that can be polymerized in a state where the raw material monomer (a) is dissolved are selected under the condition that the monomer concentration is 27% by mass or more.

The solvent used for the solution polymerization in step I has a boiling point of 60 ° C. or higher and 180 ° C. or lower from the viewpoint of controlling the molecular weight distribution and the copolymerizability of the monomer, and the Fedors method using the following formula (1) is preferable. The solubility parameter value (hereinafter, also referred to as “SP value”) according to the above is 8 (cal / cm ³ ) ^1/2 or more and 12 (cal / cm ³ ) ^1/2 or less.
δ = [ΣE _coh / ΣV] ^1/2 (1)
Here, ΣE _coh indicates the aggregation energy, and ΣV indicates the molar molecular content.

Examples of the solvent include ketones such as 2-butanone (methyl ethyl ketone; SP value 8.98); aromatic hydrocarbons such as xylene (SP value 9.10) and toluene (SP value 9.14); 1-butanol (1-butanol). SP value 11.30), 2-butanol (SP value 11.10), tert-butanol (SP value 10.90), 1-pentanol (SP value 10.90), 3-pentanol (SP value 10. 80), monohydric alcohols such as 1-hexanol (SP value 10.70); cyclic ethers such as 1,4-dioxane (SP value 9.37), tetrahydrofuran (SP value 9.00); n-di Examples thereof include linear ethers such as butyl ether (SP value 8.79).
The SP value of the solvent is preferably 12 or less, more preferably 10.5 or less, still more preferably 9.5 or less, from the viewpoint of solubility in the raw material monomer (a).
The unit of the SP value is "(cal / cm ³ ) ^1/2 ".

The monomer concentration during polymerization in step I is 27% by mass or more, preferably 30% by mass or more, more preferably 33% by mass or more, still more preferably 35, from the viewpoint of controlling the molecular weight distribution and the copolymerizability of the monomers. By mass or more, more preferably 37% by mass or more, and preferably 45% by mass or less.
In the present invention, the monomer concentration is the mass ratio of the amount of the raw material monomer (a) charged to the total amount of the raw material monomer (a) and the solvent charged.
The mass ratio is not only when the solution polymerization in step I is a batch method in which the raw material monomer (a) is charged all at once, but also when the polymerization reaction is carried out while supplying the raw material monomer (a). , Calculated based on the amount of the raw material monomer (a) and the solvent supplied to the reaction field.

It is preferable to use a polymerization initiator for the solution polymerization of the raw material monomer (a) in step I.
As the polymerization initiator, for example, a known polymerization initiator such as a peroxide such as di-tert-butyl peroxide and an azo compound such as 2,2'-azobis (2,4-dimethylvaleronitrile) is used. be able to.
The amount of the polymerization initiator is preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, and preferably 20 parts by mass with respect to 100 parts by mass of the raw material monomer (a). Parts or less, more preferably 15 parts by mass or less, still more preferably 10 parts by mass or less.

The polymerization atmosphere in step I is preferably a nitrogen gas atmosphere or an inert gas atmosphere such as argon.
The polymerization temperature in step I can be appropriately selected depending on the solvent used, the type of polymerization initiator, and the like, but from the viewpoint of controlling the molecular weight distribution and the copolymerizability of the monomer, a temperature lower than the boiling point of the solvent is preferable.
The vinyl-based resin (A) may be used as it is as a solution of the vinyl-based resin (A) for compounding with the polycondensate of the polymer (b) described later without removing the solvent used for the polymerization. From the viewpoint of improving the dispersion stability of the wax and improving the storage stability and durability, the polycondensate of the raw material monomer (b) described later is isolated from the reaction solution by a known method such as reprecipitation and solvent distillation. It is preferable to combine with. Unreacted monomers can also be removed during this isolation operation. Further, in the obtained vinyl resin (A), unreacted monomers and the like can be removed by a membrane separation, a chromatographic method, an extraction method and the like.

The weight average molecular weight of the vinyl resin (A) is preferably 3,000 or more, more preferably 5,000 or more, from the viewpoint of improving the dispersion stability of the wax in the toner and improving the storage stability and durability. More preferably 8,000 or more, still more preferably 10,000 or more, and preferably 200,000 or less, more preferably 100,000 or less, still more preferably 70,000 or less, still more preferably 50,000 or less. Is.
The weight average molecular weight can be measured by the method described in Examples.

[Polyester resin unit]
The polyester-based resin unit is preferably composed of a polyester resin which is a polycondensate of a raw material monomer (b) containing an alcohol component (b-al) and a carboxylic acid component (b-ac). Hereinafter, the alcohol component (bal) and the carboxylic acid component (b-ac) contained in the polyester resin will be described.

〔式中、ＯＲ¹¹及びＲ¹²Ｏは、アルキレンオキシ基であり、Ｒ¹¹及びＲ¹²はそれぞれ独立に、炭素数１以上４以下のアルキレン基（好ましくはエチレン基又はプロピレン基）であり、ｘ及びｙは、アルキレンオキシドの平均付加モル数であって、それぞれ独立に正の数であり、ｘ及びｙの和の平均値は、好ましくは１以上、より好ましくは１．５以上、更に好ましくは２以上であり、そして、好ましくは１６以下、より好ましくは８以下、更に好ましくは４以下、更に好ましくは３以下である。〕で表されるＢＰＡ−ＡＯが挙げられる。 (Alcohol component (b-al))
Examples of the alcohol component (b-al) include aromatic diols, aliphatic diols, alicyclic diols, and trihydric or higher polyhydric alcohols. Among these, it is preferable to contain an aromatic diol.
Examples of the aromatic diol include an alkylene oxide adduct of bisphenol A (hereinafter, also referred to as “BPA-AO”).
Among them, the alcohol component (bal) more preferably contains BPA-AO. As BPA-AO, the formula (I): is preferable.

[In the formula, OR ¹¹ and R ¹² O are alkyleneoxy groups, and R ¹¹ and R ¹² are independently alkylene groups having 1 or more and 4 or less carbon atoms (preferably ethylene or propylene groups), and x. And y are the average number of moles of alkylene oxide added, each of which is a positive number independently, and the average value of the sum of x and y is preferably 1 or more, more preferably 1.5 or more, still more preferably. It is 2 or more, and preferably 16 or less, more preferably 8 or less, still more preferably 4 or less, still more preferably 3 or less. ], BPA-AO represented by.

The BPA-AO is preferably a propylene oxide adduct of bisphenol A (hereinafter, also referred to as “BPA-PO”) and an ethylene oxide adduct of bisphenol A (hereinafter, also referred to as “BPA-EO”). These BPA-AOs may be used alone or in combination of two or more.
The amount of BPA-AO is preferably 80 mol% or more, more preferably 90 mol% or more, still more preferably 95 mol% or more, still more preferably 98 mol% or more, and more preferably 98 mol% or more in the alcohol component (bal). , 100 mol% or less, more preferably 100 mol%.

The alcohol component (b-al) may contain other alcohol components different from BPA-AO. Examples of other alcohol components include aliphatic diols, alicyclic diols, and trihydric or higher polyhydric alcohols.

The aliphatic diol preferably has 2 or more carbon atoms, and preferably 18 or less, more preferably 14 or less, still more preferably 10 or less, still more preferably 6 or less.
Examples of the aliphatic diol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 2,3-. Butanediol, neopentyl glycol, 1,4-butenediol, 1,2-pentanediol, 1,4-pentanediol, 2,4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1 , 5-Hexanediol, 2,5-hexanediol, 1,6-hexanediol, 3,3-dimethyl-1,2-butanediol, 1,7-heptanediol, 1,8-octanediol, 1,9 Examples thereof include −nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, and 1,14-tetradecanediol.
Examples of the alicyclic diol include hydrogenated bisphenol A and alkylene oxide adducts of hydrogenated bisphenol A having 2 or more and 4 or less carbon atoms (average number of moles added 2 or more and 12 or less).
Examples of the trihydric or higher polyhydric alcohol include glycerin, pentaerythritol, trimethylolpropane, sorbitol, and sorbitol.
From the viewpoint of adjusting the molecular weight and softening point of the resin, the alcohol component (bal) may contain a monohydric alcohol.
These alcohol components may be used alone or in combination of two or more.

(Carboxylic acid component (b-ac))
Examples of the carboxylic acid component (b-ac) include a dicarboxylic acid compound and a trivalent or higher valent carboxylic acid compound.

Examples of the dicarboxylic acid compound include an aromatic dicarboxylic acid compound, an aliphatic dicarboxylic acid compound, and an alicyclic dicarboxylic acid compound.
The number of carbon atoms of the dicarboxylic acid compound is preferably 2 or more, more preferably 3 or more, and preferably 30 or less, more preferably 20 or less.
Examples of the aromatic dicarboxylic acid compound include phthalic acid, isophthalic acid, and terephthalic acid. Among these, isophthalic acid and terephthalic acid are preferable, and terephthalic acid is more preferable.
Examples of the aliphatic dicarboxylic acid compound include oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, pentanic acid, adipic acid, sebacic acid, dodecanedioic acid, and azelaic acid. , Succinic acid substituted with an aliphatic hydrocarbon group having 1 or more and 20 or less carbon atoms can be mentioned. The aliphatic hydrocarbon group preferably has 8 or more carbon atoms, more preferably 9 or more carbon atoms, and preferably 16 or less, more preferably 14 or less carbon atoms. The aliphatic hydrocarbon group may be either a straight chain or a branched chain, and may be either a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. Examples of the succinic acid substituted with an aliphatic hydrocarbon group having 1 to 20 carbon atoms include octenyl succinic acid, nonenyl succinic acid, decenyl succinic acid, undecenyl succinic acid, dodecyl succinic acid, dodecenyl succinic acid, and tridecenyl succinic acid. , Tetradecenyl succinic acid, tetrapropenyl succinic acid and the like.

Among these dicarboxylic acid compounds, the carboxylic acid component (b-ac) preferably contains an aromatic dicarboxylic acid compound, and more preferably contains terephthalic acid.
The amount of the aromatic dicarboxylic acid compound is preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 65 mol% or more, still more preferably 70 mol% or more in the carboxylic acid component (b-ac). Yes, and it is 100 mol% or less, more preferably 90 mol% or less, still more preferably 85 mol% or less, still more preferably 80 mol% or less.

Examples of the trivalent or higher valent carboxylic acid compound include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, and pyromellitic acid. Among these, it is preferable to contain trimellitic acid or an anhydride thereof.
The amount of the trivalent or higher polyvalent carboxylic acid compound is preferably 10 mol% or more, more preferably 15 mol% or more, still more preferably 20 mol% or more, and more preferably 20 mol% or more in the carboxylic acid component (b-ac). It is preferably 40 mol% or less, more preferably 35 mol% or less, still more preferably 30 mol% or less.
From the viewpoint of adjusting the molecular weight and softening point of the resin, the carboxylic acid component (b-ac) may appropriately contain a monovalent carboxylic acid.
As these carboxylic acid components, one kind or two or more kinds may be used.

The equivalent ratio [COOH group / OH group] of the carboxy group (COOH group) of the carboxylic acid component (b-ac) to the hydroxy group (OH group) of the alcohol component (b-al) is preferably 0.7 or more. It is preferably 0.8 or more, preferably 1.3 or less, and more preferably 1.2 or less.

〔Release agent〕
The composite resin according to the present invention preferably further contains a mold release agent.
Examples of the release agent include waxes, fatty acid amides, fatty acids, higher alcohols, and fatty acid metal salts, but waxes are preferable from the viewpoint of improving storage stability and durability.
The composite resin according to the present invention contains a vinyl-based resin unit, and the vinyl-based resin unit improves compatibility with wax. Therefore, a required amount of wax can be easily blended in the composite resin and stored. It can be made to have excellent properties and durability.
Examples of the wax include polypropylene wax, polyethylene wax, polypropylene-polyethylene copolymer wax; hydrocarbon waxes such as microcrystallin wax, paraffin wax, Fishertropch wax, and sazole wax, or oxides thereof; carnauba wax, and the like. Examples thereof include montan wax, deoxidizing wax thereof, and fatty acid ester wax. These may be used alone or in combination of two or more.
Among these, the wax is preferably a hydrocarbon wax from the viewpoint of storage stability and durability.
When the composite resin according to the present invention contains a wax, the wax may have one or both of a hydroxyl group and a carboxy group, and may not have these hydroxyl groups and a carboxy group. There may be.
When the wax has a hydroxyl group or a carboxy group, in the composite resin, at least a part of the wax having a hydroxyl group or a carboxy group is chemically bonded to a part of the polyester resin unit via an ester bond. Can be a form.
When the wax does not have a hydroxyl group and a carboxy group, the composite resin is in a form in which the wax is physically mixed.

The melting point of the release agent is preferably 60 ° C. or higher, more preferably 70 ° C. or higher, still more preferably 75 ° C. or higher, still more preferably 80 ° C. or higher, still more preferably 85 ° C. or higher, still more preferably 90 ° C. or higher. The temperature is preferably 150 ° C. or lower, more preferably 130 ° C. or lower, and even more preferably 110 ° C. or lower.
When the composite resin contains a mold release agent, the content of the mold release agent in the composite resin is preferably 1% by mass or more, more preferably 3% by mass or more, still more preferably 5% by mass or more, and It is preferably 20% by mass or less, more preferably 15% by mass or less, and further preferably 10% by mass or less.

[Manufacturing method of binder resin for toner]
From the viewpoint of obtaining excellent storage stability and durability, the binder resin of the present invention can be made into the vinyl resin (A) by polycondensing the raw material monomer (b) in the presence of the vinyl resin (A). It contains a composite resin in which a vinyl-based resin unit and a polyester-based resin unit are composited by a covalent bond via a structural unit derived from the introduced bireactive monomer.
That is, the method for producing the binder resin of the present invention is:
Step I: A vinyl-based resin unit is formed by solution-polymerizing a raw material monomer (a) containing both reactive monomers in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more. Steps of obtaining the resin (A) and Step II: In the presence of the vinyl-based resin (A) obtained in Step I, the raw material monomers (b) constituting the polyester-based resin unit are polycondensed to form the composite resin. The process of forming and obtaining a binder resin for toner,
including.

In step II, the polycondensation reaction uses an esterification catalyst such as di (2-ethylhexanoic acid) tin (II), dibutyltin oxide, and titanium diisopropirate bistriethanolamine as a raw material monomer (b), if necessary. 0.01 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the total amount of the esterification auxiliary catalyst such as gallic acid (same as 3,4,5-trihydroxybenzoic acid) as the raw material monomer (b) Polycondensation may be carried out using 0.001 part by mass or more and 0.5 part by mass or less with respect to parts by mass.
When a monomer having an unsaturated bond such as fumaric acid is used in the polycondensation reaction, it is preferably 0.001 part by mass or more and 0 by mass with respect to 100 parts by mass of the total amount of the raw material monomer (b), if necessary. A radical polymerization inhibitor of .5 parts by mass or less may be used. Examples of the radical polymerization inhibitor include 4-tert-butylcatechol.
The temperature of the polycondensation reaction is preferably 120 ° C. or higher, more preferably 160 ° C. or higher, further preferably 180 ° C. or higher, and preferably 260 ° C. or lower, more preferably 240 ° C. or lower. The polycondensation reaction may be carried out in an inert gas atmosphere.

When the composite resin according to the present invention further contains wax as a mold release agent, as a method of blending the wax into the composite resin, from the viewpoint of improving the dispersion stability of the wax, in step II, the raw material monomer (b) Before the polycondensation of the above, the wax is mixed with either the vinyl resin (A) or the raw material monomer (b), and then the raw material monomer (b) is polycondensed in the presence of the vinyl resin (A) to form a composite. A method of forming a resin is preferable, and a method of mixing the raw material monomer (b) and wax and then performing polycondensation of the raw material monomer (b) in the presence of the vinyl resin (A) to form a composite resin is preferable. ..
That is, from the viewpoint of further improving the storage stability and durability, the step II is preferably the following step II-1.
Step II-1: After mixing the raw material monomer (b) and wax, the raw material monomer (b) constituting the polyester resin unit is polycondensed in the presence of the vinyl resin (A) obtained in step I. To form a composite resin and obtain a binder resin for toner

When a trivalent or higher valent carboxylic acid compound is used as the carboxylic acid component (b-ac) constituting the polyester resin unit of the composite resin, the polyvalent carboxylic acid is present in the presence of the vinyl resin (A). It is preferable to carry out polycondensation of the raw material monomer (b) other than the acid compound, add the polyvalent carboxylic acid compound, and further carry out a condensation reaction to form a polyester resin unit.
Further, when a polyvalent carboxylic acid compound having a valence of 3 or more is used as the carboxylic acid component (b-ac) constituting the polyester resin unit of the composite resin, and the composite resin further contains wax, 3 After mixing the raw material monomer (b) other than the polyvalent carboxylic acid compound having a valence or higher and the wax, the vinyl resin (A) is added, and in the presence of the vinyl resin (A), other than the polyvalent carboxylic acid compound. After polycondensing the raw material monomer (b) of No. 1, it is preferable to add the polyvalent carboxylic acid compound and further carry out a condensation reaction to form a polyester resin unit.

The content of the composite resin in the binder resin of the present invention is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, from the viewpoint of further improving storage stability and durability. Yes, and preferably 100% by mass or less, more preferably 100% by mass.

The softening point of the binder resin of the present invention is preferably 110 ° C. or higher, more preferably 115 ° C. or higher, still more preferably 120 ° C. or higher, and preferably 135 ° C. or lower, more preferably 132 ° C. or lower, further preferably. Is 130 ° C. or lower.
The glass transition temperature of the binder resin is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, further preferably 60 ° C. or higher, and preferably 68 ° C. or lower, more preferably 67 ° C. or lower, still more preferably 65 ° C. It is below ° C.
The acid value of the binder resin of the present invention is preferably 20 mgKOH / g or more, more preferably 23 mgKOH / g or more, still more preferably 25 mgKOH / g or more, and preferably 36 mgKOH / g or less, more preferably 34 mgKOH / g. It is g or less, more preferably 32 mgKOH / g or less.
In order to keep the softening point, glass transition temperature and acid value of the binder resin within these ranges, the type and amount of the raw material monomer (a) and the raw material monomer (b) of the vinyl resin (A), the polymerization initiator, and the catalyst This can be easily performed by adjusting the amount or the like or selecting the reaction conditions.

[Toner for static charge image development]
The toner of the present invention contains the binder resin.
The content of the binder resin is preferably 80% by mass or more, more preferably 85% by mass or more, still more preferably 90% by mass or more, and 100% by mass or less in the toner.
The toner contains, for example, toner particles and an external additive.
The toner particles preferably contain the binder resin.
The toner particles may contain, for example, a colorant, a colorant derivative, a mold release agent, a charge control agent, a magnetic material, and other additives. Among these, the toner particles preferably contain a colorant.

<Colorant>
The colorant may be either a pigment or a dye.
As the colorant, various carbon blacks produced by the thermal black method, acetylene black method, channel black method, lamp black method, etc .; grafted carbon black in which the surface of carbon black is coated with resin; niglosin dye; permanent Examples thereof include Brown FG, Brilliant First Scarlet, Pigment Green B, Pigment Blue 15: 3, Rhodamine-B Base, Solvent Red 49, Solvent Red 146, Solvent Blue 35, and the like, and mixtures thereof.

The content of the colorant is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and preferably 20 parts by mass with respect to 100 parts by mass of the binder resin from the viewpoint of improving the image density of the toner. Parts or less, more preferably 15 parts by mass or less, still more preferably 10 parts by mass or less.

<Charge control agent>
The toner of the present invention may contain a charge control agent. The charge control agent may contain either a positive charge control agent or a negative charge control agent.
These charge control agents may be used alone or in combination of two or more.

Examples of the positive charge control agent include a niglosin dye, a triphenylmethane dye containing a tertiary amine as a side chain, a quaternary ammonium salt compound, a polyamine resin, an imidazole derivative, and a styrene-acrylic resin.
Examples of the nigrosin dye include "niglosin base EX", "oil black BS", "oil black SO", "bontron N-01", "bontron N-04", "bontron N-07", and "bontron N-09". , "Bontron N-11" (all manufactured by Orient Chemical Industries Co., Ltd.). Examples of the quaternary ammonium salt compound include "Bontron P-51" (manufactured by Orient Chemical Industries Co., Ltd.), cetyltrimethylammonium bromide, and "COPY CHARGE PX VP435" (manufactured by Clariant AG). Examples of the polyamine resin include "AFP-B" (manufactured by Orient Chemical Industries Co., Ltd.). Examples of the imidazole derivative include "PLZ-2001" and "PLZ-8001" (all manufactured by Shikoku Chemicals Corporation). Examples of the styrene-acrylic resin include "FCA-701PT" (manufactured by Fujikura Kasei Co., Ltd.).

Examples of the negative charge control agent include a metal-containing azo dye, a metal compound of a benzylic acid compound, a metal compound of a salicylic acid compound, a copper phthalocyanine dye, a quaternary ammonium salt, a nitroimidazole derivative, and an organic metal compound.
Examples of metal-containing azo dyes include "Varifast Black 3804", "Bontron S-31", "Bontron S-32", "Bontron S-34", and "Bontron S-36" (above, Orient Chemical Industries Co., Ltd.) ), "Eisenspiron Black TRH", "T-77" (manufactured by Hodogaya Chemical Co., Ltd.). Examples of the metal compound of the benzylic acid compound include "LR-147" and "LR-297" (all manufactured by Japan Carlit Co., Ltd.). Examples of the metal compound of the salicylic acid compound include "Bontron E-81", "Bontron E-84", "Bontron E-88", "Bontron E-304" (all manufactured by Orient Chemical Industries Co., Ltd.), and "TN". -105 "(manufactured by Hodogaya Chemical Co., Ltd.). Examples of the quaternary ammonium salt include "COPY CHARGE NX VP434" (manufactured by Clariant AG). Examples of the organometallic compound include "TN105" (manufactured by Hodogaya Chemical Co., Ltd.).

The content of the charge control agent is preferably 0.1 part by mass or more, more preferably 0.2 part by mass or more, still more preferably 0.5 part by mass or more, and more preferably 0.5 part by mass or more, based on 100 parts by mass of the binder resin. It is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, still more preferably 5 parts by mass or less, still more preferably 2 parts by mass or less.

<Other additives>
Toner particles include other additives such as magnetic powder, fluidity improver, conductivity modifier, reinforcing filler such as fibrous substance, antioxidant, antiaging agent, and cleaning property improver. It may be contained as appropriate.

In the toner of the present invention, the content of the toner particles is preferably 80% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more, and 100% by mass or less, preferably 99% by mass. It is as follows.

The volume median particle diameter (D ₅₀ ) of the toner particles is preferably 2 μm or more, more preferably 3 μm or more, still more preferably 5 μm or more, and preferably 20 μm or less, more preferably 15 μm or less, still more preferably 10 μm. It is as follows. In the present specification, the volume median particle size (D ₅₀ ) means a particle size in which the cumulative volume frequency calculated by the volume fraction is 50% calculated from the smaller particle size.

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

Examples of the hydrophobizing agent include hexamethyldisilazane (HMDS), dimethyldichlorosilane (DMDS), silicone oil, octylliethoxysilane (OTES), and methyltriethoxysilane. Of these, hexamethyldisilazane is preferable.

When the surface treatment of the toner particles is performed using an external additive, the content of the external additive is preferably 0.05 with respect to 100 parts by mass of the toner particles from the viewpoint of the chargeability and fluidity of the toner. More than parts by mass, more preferably 0.08 parts by mass or more, still more preferably 0.1 parts by mass or more, and preferably 5 parts by mass or less, more preferably 3 parts by mass or less, still more preferably 2 parts by mass or less. Is.

[Toner manufacturing method]
The toner of the present invention may be a toner obtained by any known method such as a melt-kneading method, an emulsification phase inversion method, a suspension polymerization method, an emulsification / aggregation method, etc., but the productivity and dispersibility of the colorant From the viewpoint of the above, the pulverized toner by the melt-kneading method is preferable.

In the case of crushed toner, the method for producing the toner is, for example, step 1: a step of melt-kneading a toner raw material containing a binder resin and a colorant, and step 2: crushing and classifying the melt-kneaded product obtained in step 1. Includes a step of obtaining toner particles.

In step 1, other additives such as a charge control agent and a colorant may be contained in the toner raw material. It is preferable that these toner raw materials are mixed in advance with a mixer such as a Henschel mixer or a ball mill and then supplied to the kneader.
The temperature of melt-kneading is preferably 80 ° C. or higher, more preferably 90 ° C. or higher, further preferably 95 ° C. or higher, and preferably 160 ° C. or lower, more preferably 130 ° C. or lower.
The melt kneading in step 1 can be carried out using a known kneader such as a closed kneader, a single-screw extruder, a twin-screw extruder, or an open roll type kneader. From the viewpoint of melting and mixing the crystals, a twin-screw extruder that can be set to high temperature conditions is preferable.
The melt-kneaded product obtained in step 1 is cooled to a extent that it can be pulverized, and then subjected to the subsequent step 2.

The pulverization in step 2 may be performed in multiple stages. For example, the resin kneaded product obtained by curing the melt-kneaded product may be roughly pulverized to 1 mm or more and 5 mm or less, and then finely pulverized to a desired particle size.
As the crusher used for coarse pulverization and fine pulverization and the classifier used for classification in step 2, known devices can be appropriately selected and used.

The method for producing a toner of the present invention may further include a step of mixing the obtained toner particles with an external additive.

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

Each property of the raw material, etc. was measured and evaluated by the following method.

[measurement]
[Acid value of resin]
The acid value of the resin was measured based on the method of JIS K0070: 1992. However, in this method, only the measurement solvent was changed from a mixed solvent of ethanol and ether to a mixed solvent of acetone and toluene [acetone: toluene = 1: 1 (volume ratio)].

[Weight average molecular weight of resin]
The molecular weight distribution was measured by the gel permeation chromatography (GPC) method obtained by the following method, and the weight average molecular weight was determined.
(1) Preparation of sample solution The sample was dissolved in tetrahydrofuran at 25 ° C. so that the concentration was 0.5 g / 100 mL. Next, this solution was filtered using a fluororesin filter "DISMIC-25JP" (manufactured by ADVANTEC) having a pore size of 0.2 μm to remove insoluble matter, and used as a sample solution.
(2) Molecular Weight Measurement Using the following measuring device and analytical column, tetrahydrofuran was flowed as an eluent at a flow rate of 1 mL per minute to stabilize the column in a constant temperature bath at 40 ° C. 100 μL of the sample solution was injected therein and the measurement was carried out. The molecular weight of the sample was calculated based on a calibration curve prepared in advance. The calibration curve of the several kinds of monodisperse polystyrene "A-500" (5.0 × 10 ^2), "A-1000" (1.01 × 10 ^3), "A-2500" (2.63 × 10 ^3), "A-5000" (5.97 × 10 ^3), "F-1" (1.02 × 10 ^4), "F-2" (1.81 × 10 ^4), "F- 4 "(3.97 × 10 ^4)," F-10 "(9.64 × 10 ^4)," F-20 "(1.90 × 10 ^5)," F-40 "(4.27 × 10 ^5), "F-80" (7.06 × 10 ^5), "F-128" (1.09 × 10 ⁶⁾ (above, was used to create the Tosoh Corporation) as a standard sample.
Measuring device: "HLC-8220CPC" (manufactured by Tosoh Corporation)
Analytical column: "GMHXL" + "G3000HXL" (manufactured by Tosoh Corporation)

[Resin softening point]
Using a flow tester "CFT-500D" (manufactured by Shimadzu Corporation), while heating a 1 g sample at a heating rate of 6 ° C./min, 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 of. 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 used as the softening point.

[Resin glass transition temperature]
Using a differential scanning calorimeter "Q-20" (manufactured by TA Instruments Japan Co., Ltd.), weigh 0.01 to 0.02 g of the sample into an aluminum pan, raise the temperature to 200 ° C, and then use the sample. The temperature was cooled to 0 ° C. at a temperature lowering rate of 10 ° C./min. Next, the temperature of the sample is raised at a temperature rise rate of 10 ° C./min, and the temperature at the intersection of the extension line of the baseline below the maximum peak temperature of heat absorption and the tangent line indicating the maximum slope from the rising portion of the peak to the peak is set. The glass transition temperature was used.

[Melting point of mold release agent]
Using a differential scanning calorimeter "Q-100" (manufactured by TA Instruments Japan Co., Ltd.), 0.02 g of the sample is weighed in an aluminum pan, the temperature is raised to 200 ° C, and then the temperature is lowered from 200 ° C. It was cooled to 0 ° C. at a speed of 10 ° C./min. Next, the temperature of the sample was raised at a heating rate of 10 ° C./min, and the amount of heat was measured. The maximum peak temperature of the obtained endothermic was taken as the melting point.

[Volume medium particle size of toner particles (D ₅₀ )]
The volume median particle diameter (D ₅₀ ) of the toner particles was measured as follows.
-Measuring device: "Coulter Multisizer (registered trademark) III" (manufactured by Beckman Coulter Co., Ltd.)
・ Aperture diameter: 50 μm
-Analysis software: "Coulter Multisizer (registered trademark) III version 3.51" (manufactured by Beckman Coulter Co., Ltd.)
-Electrolytic solution: "Isoton (registered trademark) II" (manufactured by Beckman Coulter Co., Ltd.)
Dispersion: "Emulgen (registered trademark) 109P" [polyoxyethylene lauryl ether, manufactured by Kao Co., Ltd., HLB (Hydrophile-Lipophile Balance, Griffin method) = 13.6] was dissolved in the electrolytic solution to a concentration of 5 mass. % Dispersion was obtained.
Dispersion conditions: 10 mg of the measurement sample was added to 5 mL of the dispersion, dispersed for 1 minute with an ultrasonic disperser, then 25 mL of an electrolytic solution was added, and further dispersed for 1 minute with an ultrasonic disperser. A sample dispersion was prepared.
-Measurement conditions: In a beaker, the sample dispersion is added to 100 mL of the electrolytic solution to adjust the particle size of 30,000 particles to a concentration that can be measured in 20 seconds, and then 30,000 particles are measured. Then, the volume median particle size (D ₅₀ ) was determined from the obtained particle size distribution.

[Manufacturing of resin (A)]
Production Examples A1 and A4 (Production of resins A-1 and A-4)
Raw material monomer (a) containing both reactive monomers of the vinyl resin (A) shown in Table 1, and 2,2'-azobis (2,4-dimethylvaleronitrile) having an initial charge of 68 g as a radical polymerization initiator. The mixed solution is equipped with a thermometer, a stainless steel stirring rod, a flow-down condenser equipped with a dehydration tube, and a nitrogen introduction tube, and has an initial charge of 2550 g of 2-butanone (boiling point: 79 ° C., SP value: 8.98 (cal)). It was dissolved in a 5 liter four-necked flask containing / cm ³ ) ^1/2 ) and polymerized in a mantle heater at 75 ° C. for 4 hours in a nitrogen atmosphere. Then, a polymerization initiator solution containing 11 g of 2,2'-azobis (2,4-dimethylvaleronitrile) and 74 g of 2-butanone was added and the temperature was raised to 80 ° C., and then 2,2'-azobis was every hour. The step of adding the polymerization initiator solution containing 11 g of (2,4-dimethylvaleronitrile) and 74 g of 2-butanone was further carried out four times. Then, the pressure was reduced to 80 Torr, the solvent was removed for 3 hours, the temperature was further raised to 120 ° C., and the solvent was removed for 3 hours to obtain vinyl resins A-1 and A-4. Table 1 shows the monomer concentration.

Production Example A2 (Production of Resin A-2)
A mixed solution of the raw material monomer (a) containing the bireactive monomer of the vinyl resin (A) shown in Table 1 and the di-tert-butyl peroxide having an initial charge of 34 g as a radical polymerization initiator was mixed with a thermometer and stainless steel. Equipped with a flow-down condenser equipped with a stirring rod and a dehydration tube and a nitrogen introduction tube, and an initial charge of 2550 g of xylene (boiling point: about 140 ° C., SP value: 9.10 (cal / cm ³ ) ^1/2 ). The mixture was placed in a 5-liter four-necked flask and dissolved, and polymerized in a mantle heater in a nitrogen atmosphere for 4 hours under reflux conditions. Then, a polymerization initiator solution containing 6 g of di-tert-butyl peroxide and 79 g of xylene was added, the temperature was raised to 80 ° C., and then the polymerization initiator containing 6 g of di-tert-butyl peroxide and 79 g of xylene was added every hour. The step of adding the solution was performed four more times. Then, the pressure was reduced to 80 Torr, the solvent was removed for 3 hours, the temperature was further raised to 140 ° C., and the solvent was removed for 3 hours to obtain a vinyl resin A-2. Table 1 shows the monomer concentration.

Production Example A3 (Production of Resin A-3)
A mixed solution of the raw material monomer (a) containing the bireactive monomer of the vinyl resin (A) shown in Table 1 and the di-tert-butyl peroxide having an initial charge of 30 g as a radical polymerization initiator was mixed with a thermometer and stainless steel. Equipped with a flow-down condenser equipped with a stirring rod and a dehydration tube and a nitrogen introduction tube, put it in a 5-liter four-necked flask containing an initial charge of 3500 g of xylene to dissolve it, and in a mantle heater in a nitrogen atmosphere, It was polymerized for 4 hours under reflux conditions. Then, a polymerization initiator solution containing 5 g of di-tert-butyl peroxide and 70 g of xylene was added, the temperature was raised to 80 ° C., and then the polymerization initiator containing 5 g of di-tert-butyl peroxide and 70 g of xylene was added every hour. The step of adding the solution was performed four more times. Then, the pressure was reduced to 80 Torr, the solvent was removed for 3 hours, the temperature was further raised to 140 ° C., and the solvent was removed for 3 hours to obtain a vinyl resin A-3. Table 1 shows the monomer concentration.

Comparative manufacturing example A51 (manufacturing of resin A-51)
A mixed solution of the raw material monomer (a) containing the bireactive monomer of the vinyl resin (A) shown in Table 1 and the di-tert-butyl peroxide having an initial charge of 24 g as a radical polymerization initiator was mixed with a thermometer and stainless steel. Equipped with a flow-down condenser equipped with a stirring rod and a dehydration tube and a nitrogen introduction tube, put it in a 5-liter four-necked flask containing an initial charge of 3600 g of xylene to dissolve it, and in a mantle heater in a nitrogen atmosphere, It was polymerized for 4 hours under reflux conditions. Then, a polymerization initiator solution containing 4 g of di-tert-butyl peroxide and 56 g of xylene was added and the temperature was raised to 80 ° C., and then the polymerization initiator containing 4 g of di-tert-butyl peroxide and 56 g of xylene was added every hour. The step of adding the solution was performed four more times. Then, the pressure was reduced to 80 Torr, the solvent was removed for 3 hours, the temperature was further raised to 140 ° C., and the solvent was removed for 3 hours to obtain a vinyl resin A-51. Table 1 shows the monomer concentration.

Comparative manufacturing example A52 (manufacturing of resin A-52)
A thermometer was used to prepare a mixed solution of the raw material monomer (a) of the vinyl resin (A) shown in Table 1 and 2,2'-azobis (2,4-dimethylvaleronitrile) having an initial charge of 68 g as a radical polymerization initiator. Equipped with a stainless steel stirring rod, a flow-down condenser equipped with a dehydration tube, and a nitrogen introduction tube, put it in a 5 liter four-necked flask containing 2-butanone with an initial charge of 2550 g to dissolve it, and in a nitrogen atmosphere. Polymerization was carried out at 75 ° C. for 4 hours in a mantle heater. Then, a polymerization initiator solution containing 11 g of 2,2'-azobis (2,4-dimethylvaleronitrile) and 74 g of 2-butanone was added and the temperature was raised to 80 ° C., and then 2,2'-azobis was every hour. The step of adding the polymerization initiator solution containing 11 g of (2,4-dimethylvaleronitrile) and 74 g of 2-butanone was further carried out four times. Then, the pressure was reduced to 80 Torr, the solvent was removed for 3 hours, the temperature was further raised to 120 ° C., and the solvent was removed for 3 hours to obtain a vinyl resin A-52. Table 1 shows the monomer concentration.

Each notation in Table 1 is as follows.
* 1: It means the content (mass%) of each monomer in the total amount of monomers other than the bireactive monomer contained in the raw material monomer (a).
* 2: It means the amount (parts by mass) of the bireactive monomer with respect to 100 parts by mass of the total amount of the monomers other than the bireactive monomer contained in the raw material monomer (a).
* 3: Total amount charged by adding the polymerization initiator solution (g)
* 4: The monomer concentration is the mass ratio (mass%) of the charged amount of the raw material monomer (a) to the total charged amount of the raw material monomer (a) and the solvent.

[Manufacturing of binder resin]
Examples 1-1 to 1-4 and Comparative Examples 1-1, 1-2 (Manufacturing of binder resins C-1 to C-4, C-51, C-52)
Four 10-liter raw material monomers (b) of the polyester resin unit other than trimellitic anhydride shown in Table 2 equipped with a thermometer, a stainless steel rod, a flow-down condenser equipped with a stirring and dehydration tube, and a nitrogen introduction tube. It was placed in a mouth flask and stirred at 160 ° C. Then, wax W-1 (Fischer-Tropsch wax "H-105", manufactured by Sazole Wax Co., Ltd., melting point 105 ° C.) is mixed, the vinyl resin (A) shown in Table 2 is added, and the mixture is stirred at 160 ° C. for 1 hour. After that, the temperature was raised to 200 ° C. and stirring was performed at 8.0 kPa for 1 hour. Then, the esterification catalyst and the co-catalyst shown in Table 2 were added, and polycondensation was carried out in a mantle heater at 235 ° C. in a nitrogen atmosphere, and then the pressure was reduced to 60 torr and dehydration condensation was carried out for 1 hour. Then, trimellitic anhydride is added to raise the temperature to 210 ° C., and the reaction is carried out at 8.0 kPa for about 1 to 2 hours so as to reach a desired softening point to form a composite resin, and the binder resin C is formed. -1 to C-4, C-51 and C-52 were obtained.

Comparative Example 1-3 (Manufacturing of Bundling Resin C-53)
Table 3 shows a raw material monomer for a polyester resin unit other than trimellitic anhydride, acrylic acid as a bireactive monomer, an esterification catalyst, a co-catalyst as a thermometer, a stainless steel stirring rod, and a flow-down condenser equipped with a dehydration tube. The mixture was placed in a 10-liter four-necked flask equipped with a nitrogen introduction tube, polycondensed at 235 ° C. in a mantle heater in a nitrogen atmosphere, and then reduced to 60 torr and dehydrated and condensed for 1 hour. After that, the mixture was cooled to an atmospheric pressure of 160 ° C., wax W-1 (Fischer-Tropsch wax "H-105") was added, and then a mixed solution of the raw material monomer of the vinyl resin unit and the radical polymerization initiator shown in Table 3 was added for 1 hour. Dropped over. Then, after holding (aging) at 160 ° C. for 30 minutes, the temperature was raised to 200 ° C., and the reaction was further carried out under a reduced pressure of 8.0 kPa for 1 hour. After that, trimellitic anhydride was added, the temperature was raised to 210 ° C., and the reaction was carried out at 8.0 kPa so as to reach the softening point shown in Table 3 to form a composite resin to obtain the binder resin C-53. Obtained.

[Manufacturing of toner]
Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-3
100 parts by mass of the binder resin shown in Table 4 is 1 part by mass of the negative charge control agent "Bontron E-81" (manufactured by Orient Chemical Industries Co., Ltd.) and the colorant "Pigment blue 15: 3" (Dainichiseika). (Manufactured by Kogyo Co., Ltd.) After sufficiently mixing 5 parts by mass with a Henshell mixer, a roll rotation speed of 200 r / min, in the roll, using a uniaxial rotating twin-screw extruder with a total length of 1560 mm, a screw diameter of 42 mm, and a barrel inner diameter of 43 mm. The mixture was melt-kneaded at a heating temperature of 100 ° C. The supply rate of the mixture was 20 kg / h and the average residence time was about 18 seconds. The obtained melt-kneaded product was cooled and roughly pulverized, then pulverized by a jet mill and classified to obtain toner particles having _{a volume medium particle size (D 50) of 8 μm.}
To 100 parts by mass of the obtained toner particles, 2.0 parts by mass of the external additive "Aerosil R-972" (hydrophobic silica, manufactured by Nippon Aerosil Co., Ltd., number average particle diameter: 16 nm) was added, and the mixture was used with a Henschel mixer. By mixing at 3600 r / min for 5 minutes, an external additive treatment was performed to obtain toners 1-4, 51-53.

[Toner evaluation]
[Preservation]
5 g of the toners of Examples and Comparative Examples were placed in a 50 mL poly bottle and left for 48 hours in an environment of a temperature of 50 ° C. and a relative humidity of 60%. Then, the toner was sieved with a mesh having an opening of 100 μm, the residual toner on the mesh was weighed, and the storage stability was evaluated according to the following evaluation criteria. The smaller the amount of residual toner, the better the storage stability. The results are shown in Table 4.
(Evaluation criteria)
A: Residual toner is less than 0.5 g B: Residual toner is 0.5 g or more and less than 1 g C: Residual toner is 1 g or more

[durability]
The toners of Examples and Comparative Examples were mounted on a non-magnetic one-component developing printer "OKI MicroLine 18" (manufactured by Oki Data Corporation), and the blackening rate was 5.5 under the conditions of a temperature of 30 ° C. and a humidity of 80%. Percentage diagonal stripe pattern was printed. On the way, a solid black image was printed every 500 sheets, and streaks on the image were confirmed. The number of printed sheets up to the time when streaks were visually observed on the image was defined as the number of printed sheets. The larger the number of printed sheets, the better the durability. The results are shown in Table 4.

As shown in Table 4, it can be seen that the toner of the example using the binder resin containing a specific composite resin is excellent in storage stability and durability as compared with the toner of the comparative example.

Claims (10)

A binder resin for toner containing a composite resin in which a vinyl-based resin unit and a polyester-based resin unit are bonded via a covalent bond.
The composite resin is a resin obtained by polycondensing the raw material monomer (b) constituting the polyester resin unit in the presence of the vinyl resin (A) constituting the vinyl resin unit.
The vinyl resin (A) is a resin obtained by solution-polymerizing a raw material monomer (a) containing both reactive monomers in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more. There is a binder resin for toner. The binder resin for toner according to claim 1, wherein the solubility parameter value of the solvent according to the Fedors method is 8 (cal / cm ³ ) ^1/2 or more and 12 (cal / cm ³ ) ^{1/2 or less.} The binder resin for toner according to claim 1 or 2, wherein the vinyl-based resin (A) has a weight average molecular weight of 10,000 or more and 200,000 or less. The binder resin for toner according to any one of claims 1 to 3, wherein the bireactive monomer is a compound having an ethylenically unsaturated bond and one or more functional groups selected from a carboxy group and a hydroxyl group. .. The binder resin for toner according to any one of claims 1 to 4, wherein the raw material monomer (a) further contains a (meth) acrylic acid ester having a hydrocarbon group having 8 or more carbon atoms. Any of claims 1 to 5, wherein the amount of the bireactive monomer is 4 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the total amount of the monomers other than the bireactive monomer contained in the raw material monomer (a). Binder resin for toner described in Crab. The binder resin for toner according to any one of claims 1 to 6, wherein the composite resin further contains a wax. A toner for developing an electrostatic charge image, which contains the binder resin for toner according to any one of claims 1 to 7. A method for producing a binder resin for toner, which contains a composite resin in which a vinyl-based resin unit and a polyester-based resin unit are bonded via a covalent bond.
Step I: A vinyl-based resin unit is formed by solution-polymerizing a raw material monomer (a) containing both reactive monomers in a solvent having a boiling point of 60 ° C. or higher and 180 ° C. or lower at a monomer concentration of 27% by mass or more. Steps of obtaining the resin (A) and Step II: In the presence of the vinyl-based resin (A) obtained in Step I, the raw material monomers (b) constituting the polyester-based resin unit are polycondensed to form the composite resin. The process of forming and obtaining a binder resin for toner,
A method for producing a binder resin for toner, including. The method for producing a binder resin for toner according to claim 9, wherein step II is the following step II-1.
Step II-1: After mixing the raw material monomer (b) and the wax, the raw material monomer (b) constituting the polyester resin unit is polycondensed in the presence of the vinyl resin (A) obtained in the step I. To form the composite resin and obtain a binder resin for toner.