JPH0363662A - Resin composition for toner and toner - Google Patents

Abstract

PURPOSE:To improve the anti-offsetting property, fixability and blocking resistance of a toner over a wide fixing temp. range by incorporating specified two kinds of resins. CONSTITUTION:This compsn. contains resins (A), (b) and has >=40 deg.C glass transition point. The resin A has residual carboxyl groups and is obtd. by allowing a copolymer of a styrene monomer with a (meth) acrylic ester monomer and 1-20 wt.% vinyl monomer (a) having a carboxyl group to react with a compd. of a multivalent metal such a MgO in 0.1-1 molar ratio of the compd. to the monomer (a). The resin B is a copolymer of a vinyl monomer (b) having a (beta-methyl)-glycidyl group with other vinyl monomer and satisfies 0.1-10 molar ratio of the monomer (b) to the monomer (a).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a resin composition for a toner used for developing electrostatic images in electrophotography and the like, and a toner using this resin composition.

(Prior art) As a method for developing electrostatic images in electrophotography,
Dry development method is often used. This dry development method uses a triboelectrically charged fine powder developer called toner, which is a resin containing a colorant such as carbon black dispersed therein.

Normally, toner charged by friction adheres to an electrostatic latent image on a photoreceptor due to electrical attraction, forming a toner image.
This toner image is then transferred onto a sheet of paper and fixed using a heated roller that has releasability to the toner.

Such toners have a wide fusing temperature range, offset resistance (toner does not adhere to heating rollers and other cleaning rollers), fixing properties (toner firmly adheres to paper), and blocking resistance. Various performances such as (no agglomeration of toner particles) are required.

Conventionally, as this type of toner resin composition and toner,
It has been proposed to use a metal ion crosslinked resin obtained by reacting a polymer having a carboxyl group with a polyvalent metal compound (see JP-A-57-178250 and JP-A-61-110155).

(Problems to be Solved by the Invention) Although the conventional toner resin compositions and toners have relatively good performance as described above, they still have insufficient anti-offset properties particularly over a wide fixing temperature range.

The present invention is intended to solve the above problems, and its purpose is to provide a resin composition for toner that has excellent offset resistance over a wide fixing temperature range, as well as good fixing and blocking resistance. The goal is to provide toner.

(Means for Solving the Problems) The resin composition for toner of the present invention comprises a styrene monomer component (a) and a (meth)acrylate monomer component (b).
) and a vinyl monomer component (c) having a carboxyl group
The content of the monomer component (c) is 1 to 20% by weight.
A resin (A) having residual carboxyl groups obtained by reacting the copolymer with a polyvalent metal compound having a molar ratio of 0.1-1 to the monomer component (c), and a glycidyl group or β- Consisting of a vinyl monomer component (d) having a methylglycidyl group and another vinyl monomer component (e), the molar ratio of the monomer component (d) to the monomer component (c) is 0. .A resin (B) consisting of a copolymer of 1 to 10,
A composition containing as a main resin component, characterized in that the composition has a glass transition point of 40'C or higher.

Further, the toner of the present invention is characterized in that it contains the above resin composition for toner.

In the present invention, the styrenic monomer component (
Monomers for a) include styrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene, α-
Methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p-n-butylstyrene, p-tert-
Butylstyrene, pn-hexylstyrene, Pn-
Octylstyrene, pn-nonylstyrene, pn-
Examples include decylstyrene, p-n-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, and the like. Among these, styrene is preferred.

In addition, (meth)acrylic acid ester monomer component (b)
Examples of monomers include methyl (meth)acrylate, (
Ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-octyl (meth)acrylate, dodecyl (meth)acrylate, (meth)acrylic acid 2-ethylhexyl, lauryl (meth)acrylate, stearyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, α
-Methyl chloroacrylate and the like. Among these, methyl methacrylate, n-butyl (meth)acrylate, and 2-ethylhexyl acrylate are preferred.

In addition, a vinyl monomer component having a carboxyl group (c
) Monomers include (meth)acrylic acid, α-ethyl acrylic acid, crotonic acid, isocrotonic acid, β-methylcrotonic acid, fumaric acid, maleic acid, itaconic acid,
and half-ester compounds represented by the following general formula.

(However, in formula (1), L represents a divalent bonding group having 3 or more carbon atoms and having an ester bond in the molecular chain, and R1 represents a hydrogen atom or a methyl group.) The above half-ester compound is It is obtained by an esterification reaction between a (meth)acrylic acid derivative having a hydroxyl group and an aliphatic dicarboxylic acid such as succinic acid, malonic acid, or glutaric acid or an aromatic dicarboxylic acid such as phthalic acid. The dicarboxylic acid may have a hydrogen atom substituted with a halogen atom, a lower alkyl group, an alkoxy group, or the like, or may be an acid anhydride.

Such half-ester compounds include succinic acid mono(meth)acryloyloxyethyl ester and succinic acid mono(meth)acryloyloxyethyl ester.
Examples include meth)acryloyloxypropyl ester, glutaric acid mono(meth)acryloyloxyethyl ester, phthalic acid mono(meth)acryloyloxyethyl ester, phthalic acid mono(meth)acryloyloxypropyl ester, and the like.

Further, as the metal of the polyvalent metal compound, Cu, Ag
s Be s M g, , Ca, , Sr −, Ba %
Zn, Cd S/l, Tt SGe, Sn, VS
Examples include Cr sMo, Mn5Fe, Co5Ni, and the like.

Among these metals, alkaline earth metals and zinc group metals are preferred, with Mg and Zn being particularly preferred.

These polyvalent metal compounds include fluorides, chlorides, chlorates, bromides, iodides, oxides, hydroxides, sulfides,
sulfites, sulfates, selenides, tellurides, nitrides,
Examples include lower alkyl metal compounds such as nitrates, phosphides, phosphinates, phosphates, carbonates, orthosilicates, acetates, oxalates, and methylated and ethylated compounds.

Among these, acetates and oxides are preferred.

In the resin (A), the styrenic monomer components (a) and (
The copolymer consisting of the meth)acrylic acid ester monomer component (b) and the vinyl monomer component (c) having a carboxyl group can be produced by conventionally known methods such as solution polymerization, suspension polymerization, emulsion polymerization, and bulk polymerization. It can be obtained by a one-stage polymerization method or a two-stage polymerization method. In this case, the content of the styrene monomer component (a) is 40 to 95% by weight, preferably 60 to 90% by weight, and the content of the (meth)acrylic acid ester monomer component (c) is 4 to 95% by weight. 40% by weight, preferably 1
0 to 40% by weight, and the content of the vinyl monomer component (c) having a carboxyl group is 1 to 20% by weight, preferably 2
It is preferable to copolymerize so that the amount is 10% by weight.

If the content of the styrene monomer component (a) is less than 40% by weight, the pulverizability of the toner may deteriorate. In addition, (meth)acrylic acid ester monomer component (b
) If the content is less than 4% by weight, the fixing properties of the toner may deteriorate. Furthermore, if the content of the vinyl monomer component (c) having a carboxyl group is less than 1% by weight, the reaction with the polyvalent metal compound and resin (B) will be insufficient, and the offset resistance of the toner will deteriorate. Improvement effects may not appear. On the other hand, if the content of the monomer component (c) exceeds 20% by weight, the environmental dependence of the toner may deteriorate (for example, the charging stability and blocking resistance may deteriorate under high temperature and high humidity conditions, etc.). ).

In order to react the polyvalent metal compound with the copolymer, preferably, the copolymer is solution-polymerized, and then the polyvalent metal compound dispersed in an organic solvent is added to the system as necessary. The reaction is carried out at a certain temperature, and then the solvent is distilled off to produce the resin (A). In some cases, the polyvalent metal compound may be dispersed in the system together with an organic solvent before starting the polymerization reaction of the copolymer, or the solvent may be distilled off after solution polymerization of the copolymer. The resin (A) may be produced by mixing a polyvalent metal compound with the copolymer obtained by mixing the mixture and melt-kneading the mixture at an appropriate temperature using a roll mill, a kneader-1 extruder, or the like.

It is preferable to react the polyvalent metal compound in an amount such that the molar ratio to the vinyl monomer component (c) having a carboxyl group is 0.1 to 1.

The molar ratio of the polyvalent metal compound to the monomer component (c) is 0
．． If it is less than 1, the reaction with the (c) tc component may be insufficient and the effect of improving the offset resistance of the toner may not be realized. In addition, the reaction temperature is generally 100 to 2
00°C is preferred.

In the present invention, the monomer serving as the vinyl monomer component (d) having a glycidyl group or β-methylglycidyl group of resin CB) includes glycidyl (meth)acrylate,
Examples include β-methylglycidyl (meth)acrylate, allylglycidyl ether, and the like.

In addition, as the monomer to be the other vinyl monomer component (e) which is a copolymerization component of the vinyl monomer component (d) having the glycidyl group or β-methylglycidyl group, the resin ( Styrenic monomer used in A), (meth)
Other examples include acrylic acid ester monomers, vinyl acetate, vinyl propionate, vinyl chloride, ethylene, propylene, and the like. Among these, it is preferable to use a styrene monomer or both a styrene monomer and a (meth)acrylic acid ester monomer.

In the resin (B), a copolymer consisting of a vinyl monomer component (d) having a glycidyl group or a β-methylglycidyl group and another vinyl monomer component (e) can be prepared by solution polymerization or suspension. It can be produced by conventionally known one-step polymerization methods or two-step polymerization methods such as polymerization, emulsion polymerization, and bulk polymerization. In this case, it is preferable to copolymerize so that the molar ratio of the monomer component (d) to the monomer component (c) is 0.1 to 1O. If the molar ratio of monomer component (d) to monomer component (c) is less than 0.1, the reaction with resin (A) will be insufficient and the effect of improving the offset resistance of the toner will not be expressed. Sometimes.

On the other hand, if the molar ratio of the monomer component (d) to the monomer component (c) is more than 10, the reaction with the resin (A) may proceed too much, resulting in poor toner fixing properties.

The weight average molecular weight of the resin (A) is 50. OOO
The weight average molecular weight of the resin (B) is preferably in the range of 10,000 to 500,000. Further, the glass transition points of both resin (A) and resin (B) are preferably 40°C or higher.

In the present invention, a resin composition for toner is prepared by mixing or kneading the resin (A) and resin (B). The blending ratio of resin (A) and resin (B) varies depending on the amount of residual carboxyl groups and the amount of glycidyl groups or β-methylglycidyl groups, but generally resin (B) is added to 100 parts by weight of resin (A). The range of 1 to 50 parts by weight is preferred.
If the resin (B) is less than 1 part by weight, the reaction with the resin (A) may be insufficient and the effect of improving the offset resistance of the toner may not be exhibited. On the other hand, if the amount of resin (B) exceeds 50 parts by weight, toner fixability deteriorates, and resin (A
) characteristics may be lost.

Further, it is preferable that the glass transition point of the toner composition is 40°C or higher. If the glass transition point of the composition is lower than 40°C, the storage stability and fluidity of the toner may deteriorate.

To mix or knead resin (8) and resin (B), resin (A) and resin (B) are finely pulverized and mixed using a ribbon blender, Hensel mixer, etc., or resin (8) is mixed or kneaded with resin (8).
A) and resin (B) are melt-kneaded using a roll mill, kneader-5 extruder, etc. at a temperature of, for example, 100 to 200°C, cooled and pulverized, or resin (A) and resin (
B) may be dissolved in an organic solvent and mixed, and then the solvent may be distilled off to form a fine powder. In this way, the resin composition for toner of the present invention is produced.

The toner resin composition of the present invention may contain polystyrene, polyvinyl acetate, polyvinyl chloride, boria chloride resin, polyethylene, polypropylene, polyester resin, styrene-butadiene, within a range that can achieve the object of the present invention. Resins such as copolymer resins, acrylic resins, epoxy resins, and other additives may be mixed.

To produce a toner using the resin composition for toner of the present invention, add a coloring agent such as carbon black and other conventionally known colorants to the finely pulverized product of the resin (A) and resin (B) as required. Mix the toner additives with a ribbon blender, Hensel mixer, etc., or mix the resin (^) and resin (B) with a colorant such as carbon black and other conventional toner additives as necessary. Then, use a roll mill, kneader-2 extruder, etc. to heat the mixture to, for example, 100 to 200"C.
The mixture is melt-kneaded at a temperature of , cooled and pulverized. Thus,
A toner of the present invention is produced.

(Function) The toner resin composition and toner of the present invention have a styrene monomer (a), a (meth)acrylic acid ester monomer component (b), and a vinyl-based monomer having a carboxyl group as the structure t2 component. Monomer component (c)
Residual carboxyl obtained by reacting (metal ion crosslinking) a copolymer having a content of 1 to 20% by weight with a polyvalent metal compound having a molar ratio of 0.1 to 1 to the monomer component (c). Since it contains the resin (A) having a group, it has good anti-offset properties, fixing properties, and anti-blocking properties like the conventional toners.

Furthermore, the monomer component (d) has a glycidyl group or β-methylglycidyl group and another vinyl monomer component (e), and the monomer component (d) has a monomer component (c). The molar ratio of the mass component (d) is from 0.1 to
Contains a resin (B) consisting of a copolymer of 10, and
l1rIi, the glass transition point of the product is said to be 40°C or higher, and the glycidyl group or β-methylglycidyl group of this resin (B) reacts well with the residual carboxyl group of the resin (A) during heating (crosslinking). Therefore, it is presumed that the (crosslinking) reaction between the resin (^) and the resin (B) progresses during the toner manufacturing process and the toner usage process, increasing the molecular weight of the resin composition. , offset resistance is improved compared to the conventional toner.

(Example) Examples and comparative examples of the present invention are shown below.

1. Styrene component 70 parts by weight and butyl methacrylate 2.
100 parts by weight of a copolymer consisting of 5% by weight and 5% by weight of succinic acid monomethacryloyloxyethyl ester component and 0.8 parts by weight of calcium acetate were reacted with stirring under toluene reflux for 2 hours, and then the toluene was distilled off. Resin (A)-1 having a weight average molecular weight of 210,000 and a glass transition point of 68°C and having residual carboxyl groups was produced. The molar ratio of calcium acetate to the monomethacryloyloxyethyl succinate component is 0.24.

The weight average molecular weight was determined by gel permeation chromatography (
GPC). In addition, the glass transition point was measured using a differential scanning calorimeter (DSC).
i Styrene component 70% by weight and methyl methacrylate component 15%
Copolymer consisting of 10% by weight of butyl acrylate and 5% by weight of monomethacryloyloxyethyl succinate component 100! Okabe and calcium acetate 0.7
parts by weight were reacted in the same manner as in Production Example 1 to produce Resin (A)-2 having a residual carboxyl group with a weight average molecular weight of 156,000 and a glass transition point of 65°C.

100 parts by weight of a copolymer consisting of 80% by weight of a styrene component, 5% by weight of a methyl methacrylate component, 10% by weight of a butyl acrylate component, and 5% by weight of a methacrylate component, and 0% by weight of a methacrylic acid component. .5 parts by weight were reacted in the same manner as in Production Example 1 to obtain a resin (A) having a residual carboxyl group with a weight average molecular weight of 150,000 and a glass transition point of 65°C.
3 was manufactured.

100 parts by weight of a copolymer consisting of 75.5% by weight of a styrene component, 8% by weight of a methyl methacrylate component, 16% by weight of a butyl acrylate component, and 0.5% by weight of an acrylic acid component and 0.7 parts by weight of zinc oxide were reacted in the same manner as in Production Example 1 to produce a resin (A') having a residual carboxyl group and a weight average molecular weight of 150.000 and a glass transition point of 64°C.

After polymerizing glycidyl methacrylate, styrene, and butyl acrylate in the presence of a polymerization initiator benzoyl peroxide under refluxing toluene for 2.5 hours, the toluene was distilled off. , a copolymer consisting of 55% by weight of glycidyl methacrylate, 35% by weight of styrene component, and 10% by weight of butyl acrylate, with a weight average molecular weight of 49,00.
0, a resin having a glycidyl group with a glass transition point of 48°C (
B)-1 was produced.

Town 1゛2 Glycidyl acrylate, styrene, and butyl methacrylate were polymerized in the same manner as in Production Example 1, and 20% by weight of the glycidyl acrylate component, 70% by weight of the styrene component, and 10% by weight of the butyl methacrylate component. A copolymer with a weight average molecular weight of 25,000 and a glass transition point of 61°.
Resin (B)-2 having a glycidyl group of C was produced.

B-3 Glycidyl methacrylate, styrene, and butyl acrylate were polymerized in the same manner as in Production Example 1 to obtain 45% by weight of the glycidyl methacrylate component and 45% by weight of the styrene component.
A copolymer consisting of 10% by weight of butyl acrylate and a weight average molecular weight of 40,000 and a glass transition point of 51".
Resin (B)-3 having a glycidyl group of C was produced.

B° 4 Glycidyl methacrylate and styrene were polymerized in the same manner as in Production Example 1 to form glycidyl methacrylate component 7.
A copolymer consisting of 0% by weight and 45% by weight of a styrene component, with a weight average molecular weight of 80°000 and a glass transition point of 51"
Resin (B)-4 having a glycidyl group of C was produced.

Contains 1,100 parts by weight of resin (A) and 1,20 parts by weight of resin (B).
parts by weight and 5 parts by weight of carbon blank (Diablack sH, manufactured by Mitsubishi Kakaisha) were roll-kneaded at 170''C for 10 minutes, coarsely ground after cooling, and further finely ground with a jet mill to obtain an average particle size of 11, A toner of 1/11 was produced.The glass transition point of this toner was 58°C.In addition, in this toner, the molar ratio of the glycidyl methacrylate component to the monomethacryloyloxyethyl succinate component was 3.6. be.

10 g of this toner was placed in a 100-degree beaker and left in a constant temperature bath at 60° C. for 24 hours, and blocking resistance was evaluated based on whether or not the particles coalesced. As a result, the blocking resistance was good.

A fine powder developer using this toner is transferred to an electrophotographic copying machine (
11-Bix 2500 (manufactured by Konica) was installed on a modified machine to measure the fixing temperature range. This fixing temperature range is
The set temperature of the heating roller for fixing was changed to show the set temperature that allows good fixing without causing offset. As a result, the fixing temperature range was 160 to 240°C, and good fixing was possible over a wide temperature range.

Further, the fixing properties of images obtained by setting the temperature of the heating roller for fixing at 170° C. were measured. The fixability was determined by rubbing the image with a fastness tester and using a Macbeth densitometer to show the image retention rate. As a result, the fixability was 94%, which was good. Furthermore, the charged state of the toner particles was stable, and the resulting images were clear and free of fog.

The above results are summarized in Table 1. In the resin composition shown in the table, the polyvalent metal ion (polyvalent metal compound) is the polyvalent metal compound relative to 100 parts by weight of the copolymer constituting the resin (A). It is indicated by the number of parts.

亥枞绻1 Resin (A) - 2,100 parts by weight and resin (B) - 2,40 parts by weight
The same procedure as in Example 1 was conducted except that parts by weight were used. The results are summarized in Table 1.

1 100 liters of resin (A)-3,100 liters of resin (B)-3,
The same procedure as in Example 1 was conducted except that 20 parts by weight was used. The results are summarized in Table 1.

Example 1 was carried out in the same manner as in Example 1, except that 100 M parts of resin (A'') and 2.35 parts by weight of resin (B) were used as comparative amounts.

The results are summarized in Table 1.

Comparison of resin (A) - 1,100 parts by weight and resin (B) - 3,70 parts by weight
The same procedure as in Example 1 was conducted except that parts by weight were used. The results are summarized in Table 1.

The same procedure as in Example 1 was carried out except that only 1,100 parts by weight of resin (A) was used. The results are summarized in Table 1.

(The following is a blank space) (Effects of the Invention) As described above, the toner resin composition and toner of the present invention contain a specific resin (A) having a residual carboxyl group and a specific resin having a glycidyl group or a β-methylglycidyl group. resin (B), and thereby has excellent anti-offset properties over a wide fixing temperature range, as well as good fixing properties and anti-blocking properties. Furthermore, the charged state of the toner particles is stable, and the resulting images are clear and free of fog.

Therefore, the toner resin composition and toner of the present invention can be suitably used in an electrophotographic copying machine using a heating roller fixing method ranging from low speed to high speed.

Claims (1)

[Claims] 1. A monomer consisting of a styrene monomer component (a), a (meth)acrylic acid ester monomer component (b), and a vinyl monomer component having a carboxyl group (c). Mass component (c)
A resin having residual carboxyl groups obtained by reacting a copolymer having a content of 1 to 20% by weight with a polyvalent metal compound having a molar ratio of 0.1 to 1 to the monomer component (c) ( A), vinyl monomer component (d) having a glycidyl group or β-methylglycidyl group and other vinyl monomer components (
e) and a resin (B) consisting of a copolymer in which the molar ratio of the monomer component (d) to the monomer component (c) is 0.1 to 10, the resin (A) and the resin (B); ) as a main resin component, the composition has a glass transition point of 4.
A resin composition for a toner, characterized in that the temperature is 0°C or higher. 2. A toner comprising the toner resin composition according to claim 1.