JPH06332225A - Production of capsule type toner - Google Patents

Abstract

PURPOSE:To ameliorate the narrowness of the degree of freedom in designing resin compsn. and control of electrostatic charge characteristics, etc., which are the only difficulties in the process for production of the conventional type of obtaining the capsule type toners by the self-emulsification effect of a self- dispersible resin and above all to improve the electrostatic charge characteristics, fixability, flow property, etc. CONSTITUTION:This process for production consists in dispersing a mixture composed of non-water-soluble resins which are non-water-soluble resins as represented by acrylic resins, styrene resins, polyester resins or urethane resins and have neutralized acidic groups or neutralized basic groups, coloring agents and org. solvents into an aq. medium in the presence of dispersion stabilizers, then separating these formed particles from the aq. medium and drying the particles.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel and useful method for producing a capsule type toner. More specifically,
The present invention uses a mixture of a specific water-insoluble resin and colorants for phase inversion emulsification in an aqueous medium in the presence of dispersion stabilizers for developing an electrostatic latent image. The present invention relates to a novel method of manufacturing a toner.

[0002]

As a powder toner for forming an electrostatic latent image into a visible image, a colorant and so-called additives such as a release agent and a charge control agent are melt-kneaded with a toner resin. It is a general method to disperse the product by caulking, and after cooling, mechanically grind it and classify it to obtain it.

However, the toner obtained by such a method is unavoidably caused by variations in electric characteristics caused by non-uniformity of mixing of colorants and additives.
Poor fluidity due to irregular particle shape,
When the colorants are conductive like carbon,
The electrical characteristics are not stable because it cannot be completely covered with resin, the yield is low when the particle size is reduced, and the limit of the amount of colorants added is low. There are various problems such as the problem.

In addition, in the production of such toner itself, it is also difficult to consume a large amount of electric energy for melt-kneading or pulverizing. For high resolution toners in the future, it is necessary to reduce the particle size to a level of 5 microns (μm) (currently, it is within the range of 10 to 15 μm) and to increase the concentration of colorants. However, it is the fact that the crushing method cannot meet these demands.

As a method other than the so-called pulverization method, various polymerization methods have been studied. For example, JP-A-57-53756 and JP-A-59-16.
A method based on a suspension polymerization method is proposed in Japanese Patent Laid-Open No. 1-58, JP-A-59-123851 and the like.

By the way, in the suspension polymerization method, colorants and additives are dispersed in a monomer, which is then dispersed in an aqueous medium in the presence of a suspension stabilizer. It is a method of polymerizing under shear,
These colorants and additives do not necessarily have an affinity with the monomers, and it is extremely difficult to stably mix and disperse them with a low viscosity such as a monomer. .

For this reason, it is sometimes the case during the polymerization that the polymer particles migrate into the aqueous phase and that the polymer particles no longer contain colorants or additives. Alternatively, conversely, during polymerization, the colorants may agglomerate to form blocks of the colorants, increasing non-uniformity.

In particular, colorants having a small so-called primary particle size, such as carbon, may become considerably strong secondary agglomerates, causing poor dispersion in the monomers, and charging the toner particles. Variation in characteristics, and by extension,
Increase the variation in image density.

By the way, JP-A-63-100466 and JP-A-61-249816 also propose a method by a so-called non-aqueous polymerization method. Such a non-aqueous polymerization method is applied to organic solvents having an SP value larger than the solubility parameter (SP value) of the resin to be produced,
This is a method in which colorants, dispersion stabilizers and monomers are added and polymerized, and then the organic solvents are removed. In essence, the method is the same as in the case of the suspension polymerization method. It is extremely difficult to uniformly incorporate colorants and additives therein.

In addition, the resin composition, the kind of the solvent, the kind of the colorants and the amount thereof used are subject to restrictions, and control of the polymerization becomes complicated. So-called, as an improvement of the pulverization method, although various means for improving it by various polymerization methods have been proposed, in each case, the monomers and the colorants and additives are mixed and dispersed. From the point of polymerization, it is extremely difficult to uniformly contain colorants and additives in the particles, and a sufficiently satisfactory toner cannot be obtained.

[0011]

However, as a means for solving the problems or difficulties of the pulverization method and the polymerization method, the present inventor has proposed a new method for producing a toner.
It is shown in Japanese Patent Application No. 3-224227.

It is obtained by dispersing the self-water-dispersible resin and the colorants by a wet method and then neutralizing a part of the acid groups in the self-water-dispersible resin with a base. After that, by performing phase inversion emulsification in an aqueous medium, a method of producing the target toner particles, the characteristic feature of this production method is the self-emulsifying action of the self-water-dispersible resin, The point is to generate capsule-type toner particles.

However, in the case of such a method, in order to generate toner particles, it is necessary to introduce a certain amount or more of hydrophilic groups into the self-water-dispersible resin, and as a result,
The degree of freedom in designing the resin composition is narrow, and it is difficult to control the charging characteristics.

That is, the problem to be solved by the present invention is, in part, to provide capsule type toner particles by the self-emulsifying action of the self-water-dispersible resin disclosed in Japanese Patent Application No. 3-224227. The only difficulty in the novel method of generation is that the degree of freedom in designing the resin composition is narrow, and problems such as control of charging characteristics are improved.

[0015]

Therefore, as a result of intensive studies, the present inventor has paid attention to a method for producing capsule particles by phase inversion emulsification, and has utilized such means to obtain toner particles. He came up with a new manufacturing method.

That is, according to the present invention, a mixture of a specific water-insoluble resin having a neutralized acidic group or a neutralized basic group, a colorant, and an organic solvent is dispersed and stabilized. An object of the present invention is to provide a method for producing a capsule type toner, which comprises dispersing in an aqueous medium in the presence of agents to produce particles, and then separating the particles thus produced from the aqueous medium and drying. To do.

Here, a step of mixing and dispersing a water-insoluble resin having a neutralized acidic group or a neutralized basic group, a colorant, and an organic solvent is the first step, and then, The step of dispersing the mixed dispersion obtained in the first step in the presence of dispersion stabilizers in an aqueous medium to produce particles is referred to as the second step, and then the second step. The particles obtained by the above, the step of separating and drying from the aqueous medium as the third step, such a series of steps,
Below, it abbreviates as a 1st, 2nd, or 3rd process, respectively.

The resin used in the first step is a so-called water-insoluble resin which is insoluble in water. Of course, some water-soluble resins are not suitable for the production method of the present invention because capsule particles having a constant particle size cannot be obtained.

The resin system used may be any of acrylic resin, styrene resin, polyester resin or urethane resin. The introduction of the acidic group or the basic group into the water-insoluble resin can be easily performed by any known and commonly used means.

The subsequent production of particles in the second step is carried out by phase inversion emulsification by the use of dispersion stabilizers. Usually, in order to form particles by phase inversion emulsification of a hydrophobic resin in an aqueous medium with a dispersion stabilizer,
The problem is that the amount of the dispersion stabilizers added is large, and the influence of the dispersion stabilizers on the charging characteristics cannot be ignored.

The use of the water-insoluble resin having the neutralized acidic group or the neutralized basic group used in the first step significantly increases the amount of the dispersion stabilizers in the second step. Can be reduced.

As a result, not only is it easy to wash the dispersion stabilizers used, but in some cases, even if the operation of removal is completely absent,
It has a great feature that the charging characteristics of the toner are never adversely affected.

That is, in the method for producing a capsule-type toner using the self-water-dispersible resin, a part or all of the self-emulsifying resin is used to generate particles by utilizing the self-emulsifying ability of the self-dispersible resin. A certain amount or more of the neutralized form of the acidic group or basic group was required.

For this reason, the degree of freedom in designing the resin composition is narrow, and it is sometimes difficult to control the charging characteristics.

However, according to the production method of the present invention, even when the resin cannot be self-emulsified, it is possible to produce capsule type toner particles by using it together with a dispersion stabilizer, which is a so-called tremendous merit. It is a translation.

Therefore, the introduction amount of the acidic group or the basic group can be greatly reduced as compared with the conventional method. In addition, it is possible to further reduce the amount of the dispersion stabilizers used, as compared with a resin having no neutralized acidic group or basic group.

This is because by introducing a neutralized acidic group or basic group into the water-insoluble resin, the resin alone has a self-emulsifying ability sufficient to form particles. This is because even if it is not carried out, phase inversion emulsification becomes possible and particles can be produced by the synergistic action of these water-insoluble resins and the emulsifying power of the dispersion stabilizers.

Next, in the case of the acrylic or styrene resin as the water-insoluble resin, the manufacturing method thereof will be described in more detail.

The acrylic or styrene-based water-insoluble resin is synthesized by ordinary radical polymerization. First, the introduction of the acidic group, as the radical polymerizable monomer containing an acidic group, for example, acrylic acid, methacrylic acid,
Crotonic acid, itaconic acid, maleic acid, fumaric acid, monobutyl itaconate or monobutyl maleate,

Alternatively, by using acid phosphooxyethyl methacrylate, acid phosphooxypropyl methacrylate, 3-chloro-2-acid phosphooxypropyl methacrylate, 2-acrylamido-2-methylpropanesulfonic acid or 2-sulfoethyl methacrylate. To be achieved.

On the other hand, the introduction of the basic group is carried out by introducing a nitrogen-containing (meth) acrylate as the basic group-containing radically polymerizable monomer, for example, dimethylaminoethyl (meth) acrylate or diethylaminoethyl (meth). ) It is achieved by using acrylate or the like.

Examples of other radically polymerizable monomers include various styrenic monomers such as styrene, vinyltoluene, 2-methylstyrene, t-butylstyrene or chlorostyrene; methyl acrylate, Ethyl acrylate, isopropyl acrylate,
N-Butyl acrylate, isobutyl acrylate, n-amyl acrylate, isoamyl acrylate, n acrylate
Various acrylates such as hexyl, 2-ethylhexyl acrylate, n-octyl acrylate, decyl acrylate or dodecyl acrylate;

Methyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, decyl methacrylate or methacrylic acid. Various methacrylic acid esters such as dodecyl acid;

Alternatively, various hydroxy group-containing monomers such as hydroxyethyl (meth) acrylate or hydroxypropyl (meth) acrylate; such as N-methylol (meth) acrylamide or N-butoxymethyl (meth) acrylamide, In addition to various N-substituted (meth) acrylic monomers, various halogen element-containing monomers or organosilicon-containing monomers can be used, and they are appropriately copolymerized according to various characteristics. Can be done.

In some cases, the copolymer may be a copolymer of polymerizable monomers and a polymerizable vinyl group-containing oligomer. Furthermore, in the oligomer having a polymerizable vinyl group, a form having an acid group or a basic group can also be used.

Specific examples of the oligomer having a polymerizable vinyl group include only vinyl-modified polyester. The vinyl-modified polyester is, for example, maleic anhydride, fumaric acid,
Tetrahydrophthalic anhydride, endomethylene tetraphthalic anhydride, α-terpinene maleic anhydride adduct, monoallyl ether of triol, pentaerythritol diallyl ether or allyl glycidyl ether, etc. are used for polycondensation or The addition serves to introduce vinyl groups into the backbone.

Further, as the one having an acid group introduced into the polyester, a dibasic acid such as phthalic acid is excessively used, and one having a carboxyl group at the terminal or trimellitic anhydride is used. Those having an acid group in the main chain, and the like.

Examples of vinyl-modified urethane include, for example,
Examples thereof include those obtainable by addition polymerization of polyols such as glycerin monoallyl ether, butadiene polyol containing a 1,2-bond and the like, and a diisocyanate compound.

Alternatively, polyurethanes having an isocyanate at the terminal (isocyanate prepolymers)
The vinyl group can be introduced also by an addition reaction with a hydroxyl group-containing polymerizable monomer.

In addition, dimethylolpropionic acid, etc.,
The acid component can also be introduced into the polyurethane by adding it as a polyol component.

Examples of polyethylene glycol monomethacrylates include those having an average molecular weight of polyoxyethylene chains of 1,000 to 4,000.

Examples of the vinyl-modified epoxy include those in which a vinyl group is introduced by reacting (meth) acrylic acid with a terminal epoxy group.

Further, oligomers of a polymerizable monomer having a polymerizable vinyl group in a form obtained by adding a glycidyl group-containing polymerizable monomer to a carboxyl group-containing vinyl copolymer can be mentioned.

It goes without saying that the polymerizable monomers used here may be selected from those listed above.

In addition, commercially available macromonomers such as Toa Gosei Chemical Industry Co., Ltd.
The terminal vinyl-modified oligomers of can also be used.

Needless to say, all that is necessary is an oligomer having a radically polymerizable vinyl group, and therefore, it is by no means limited to the types and methods described above.

The polymerization is usually carried out using polymerization initiators. As the polymerization initiators, those usually used are used. Of these, only typical ones are exemplified, and various peroxides such as benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide, t-butyl peroxide or 2-ethylhexanoate are used. Oxides; or various azo compounds such as azobisisobutyronitrile.

As the reaction solvents, only representative ones are exemplified. Various aromatic hydrocarbons such as toluene, xylene or benzene; various aromatic hydrocarbons such as methanol, ethanol, propanol or butanol. Alcohols; various ether alcohols such as cellosolve or carbitol;

So-called inert solvents such as various ketones such as acetone, methyl ethyl ketone or methyl isobutyl ketone; various esters such as ethyl acetate or butyl acetate; various ether esters such as butyl cellosolve acetate Is.

Preferably, in the third step described below,
The use of so-called low-boiling solvents, such as acetone, methyl ethyl ketone or ethyl acetate, which can be easily desolvated, is desirable.

The polymerization conditions are usually 50 to 150 ° C.
In general, it is carried out at a temperature within the following range and under a nitrogen atmosphere, but in the method of the present invention,
It is by no means limited to this.

The amount of the acidic group or the basic group to be introduced into the water-insoluble resin is preferably within the range of 3 to 100 mg equivalent per 100 g of the solid content of the resin.

The degree of affinity of the resin for water is controlled by the amount of neutralization of acidic or basic groups. When the amount of the above-mentioned functional group is small, or when the resin has high hydrophobicity, it is desirable to increase the neutralization amount in order to increase the hydrophilicity of the resin.

On the other hand, when the amount of the functional group is relatively large, the amount of neutralization or the degree of neutralization is sufficient to neutralize a part of the functional group. When the amount of the functional group is less than 3 milligram equivalent per 100 g of the resin solid content, the effect of reducing the amount of the dispersion stabilizer used in the second step is inevitably reduced.

On the other hand, when the amount of the functional group is more than 100 milligram equivalent per 100 g of the resin solid content, the amount of the functional group on the surface of the particle is increased and the so-called charging characteristics such as environmental stability are adversely affected. It is not preferable because it easily comes out.

Among them, the use of a carboxyl group as the acidic group and the use of a tertiary amino group as the basic group are desirable treatments from the viewpoint of improving hydrophilicity by neutralization and also from the viewpoint of charging characteristics. Is.

The first step in the production method of the present invention is a step of dispersing the colorants in the resin, and as the dispersing means, a known and commonly used means such as a bead mill can be adopted. However, it may be finely dispersed by such means.

Since this ground step is carried out by a wet method, the dispersibility of the colorants is very good. And
The content of the colorants to be used is appropriately in the range of 3 to 50% by weight based on the resin solid content.

As the colorants used here, dyes and pigments that have been used as toner materials so far have been used, but only typical ones are exemplified. If you keep it, zinc yellow, yellow iron oxide,
Starting with Hansa Yellow, Disazo Yellow, Quinoline Yellow or Permanent Yellow,

Alternatively, permanent red, rouge, resole red, pyrazolone red, lake red C, lake red D, brilliant carmine 6B, brilliant carmine 3B or navy blue phthalocyanine.
blue,

Alternatively, various pigments or oil-soluble dyes such as metal-free phthalocyanine, titanium oxide or carbon black are used. For black toner, only the magnetic powder is used and the coloring agent is used. It can be used instead of.

As the above magnetic powder, only representative examples are alloys or compounds of iron, zinc, cobalt, nickel or manganese such as various ferrites, magnetites or hematites.

These magnetic powders are preferably spherical, cubic, regular octahedral, or acicular, and have an average particle size within the range of 0.1 to 0.5 micron. It may be in a so-called surface-treated form so that it has a good dispersibility in a solution.

In the subsequent second step, the resin mixture obtained by mixing and dispersing the colorants is added in the presence of the dispersion stabilizers.
This is a process of phase inversion emulsification in an aqueous medium. The acidic group or basic group in the water-insoluble resin, before the phase inversion emulsification, in the case of an acidic group, for example, a primary amine,
A certain amount is neutralized with weak bases such as secondary or tertiary amines.

In the case of a basic group, a predetermined amount is neutralized with a weak acid such as acetic acid. Furthermore, when the acidic group is a carboxyl group, strong bases such as sodium hydroxide are used, and when the basic group is a tertiary amino group, strong acids such as hydrochloric acid or sulfuric acid are used. It can also be neutralized.

The dispersion stabilizers may be added at the time of dispersing the resin and the colorants, may be added to the resin mixture, or may be partly or wholly added to the aqueous medium. May be.

The dispersion stabilizers may be of any kind as long as they are water-soluble, but of these, only representative ones will be shown below. Is like.

Thus, for example, various fibrous materials such as hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose or cellulose propionate; polyvinyl acetate, ethylene-vinyl alcohol copolymer or vinyl alcohol-vinyl acetate copolymer. Such as various polyvinyl alcohols; or various polymerized polymers such as polyvinylpyrrolidone, polyacrylic acid polyvinyl methyl ether, acrylic resin or styrene-acrylic resin; or various polycondensation such as polyester resin or polyethyleneimine Such as polymers.

Ordinary surfactants include polyoxyethylene (-alkyl allyl ether type, -alkyl ether type, -alkyl ester type or alkyl amine type) surfactants; or sulfonate type, sulfate type, Various kinds of surfactants such as phosphate type or quaternary ammonium salt type surfactants can be used, and betaine type surfactants can also be used.

These dispersion stabilizers are usually used in an amount of 0.1 to 20% by weight based on the solid content of the resin, but preferably 0.1 to 20% by weight. 1
A range of 0% by weight is suitable.

The amount of the dispersion stabilizers used is 0.1% by weight.
If the amount is smaller than the above, the resin mixture cannot be uniformly phase-inversion emulsified because the emulsifying power is inevitably reduced, so that aggregates tend to occur or the particle size distribution tends to spread. , Not preferred, while 1
When it is used in an amount of more than 0% by weight, the charging characteristics of the toner may be affected depending on the kind of the dispersion stabilizer.

In addition to particle formation, the second step involves particle size control, another important factor.
The particle size can be controlled by adjusting the amount of dispersion stabilizers and, in some cases,
It is also possible depending on the neutralization amount of the acidic group or basic group in the water-insoluble resin.

Further, the particle size and its distribution change depending on the stirring speed during phase inversion emulsification, the temperature, the addition of a cosolvent, or the viscosity of the resin mixture in which the colorants are mixed and dispersed. It is necessary to appropriately determine the conditions depending on the case.

Of these, a viscosity of 600 centipoise or less is suitable.

The above-mentioned third step is to remove the organic solvent and the aqueous medium to obtain powdery dry capsule particles. Since the encapsulated toner particles obtained in the second step are dispersed in a medium such as water and an organic solvent, the organic solvent is first removed by vacuum distillation. As such an organic solvent, the use of a low boiling point one,
It is desirable because it is easily distilled off.

Then, a wet cake of toner particles is obtained by suction filtration, and then freeze-dried.
Alternatively, powdery capsule type toner particles can be obtained by drying with a spray dryer.

The water-insoluble resin having a neutralized acidic group or basic group has a neutralized functional group covering the surface, and in some cases, due to interaction between particles,
There is a tendency for aggregation or fusion during the drying process.

Such a problem can be solved by finishing the encapsulation in the second step and then treating with an acid or a base to restore the original acidic group or basic group.

That is, by returning to the original functional group, the hydrophilicity of this functional group is lowered, the stability in the aqueous medium is lost, and the separation from the aqueous medium becomes easy.

Further, since the interaction between particles is lost, there is a merit that fusion during drying is prevented. However, the acid or base used here can be more easily returned to the original acidic group or basic group by using an acid or base stronger than the acidic group or basic group introduced into the water-insoluble resin. Can be done.

Further, it is desirable to wash and remove the dispersion stabilizers used in the phase inversion emulsification. As a washing method, washing with deionized water and performing a filtration operation several times, or washing with a solvent such as methanol, which does not dissolve the resin, and then filtering may also be performed. preferable.

However, as described above, in the case of a water-insoluble resin having a neutralized acidic group or a neutralized basic group, the amount of the dispersion stabilizers is higher than that in the case where there is no functional group. As described above, the cleaning operation is simple and, in some cases, is not always necessary because it can be greatly reduced.

Further, the operation of returning the neutralized acidic group or the neutralized basic group to the original acidic group or basic group and the operation of washing the dispersion stabilizer are ionic. When the dispersion stabilizers are used, it is desirable to first wash the dispersion stabilizers and then restore the original functional groups.

However, this does not apply when nonionic dispersion stabilizers are used.

To offset the toner, if necessary, a polypropylene wax, a polyethylene wax, a silicon compound or carnauba wax,
It is improved by blending various waxes.

In the method of the present invention, the above waxes are added in the first step of mixing and dispersing the water-insoluble resin and the colorants, and the same procedure as for the colorants is carried out.
By mixing and dispersing in this resin, it is possible to uniformly disperse and contain in the particles.

In this case, the amount of the additives to be added is appropriately in the range of 0.1 to 5% by weight based on the resin solid content containing the colorants.

In the present invention, charge control agents may be blended in order to control charge. As a method of adding the same, as in the case of the waxes described above, it can be added in the step of mixing and dispersing the colorants and the resin in the first step and incorporated into the particles.

That is, the charge control agents are incorporated into the highly hydrophilic particle surface and give desired charge characteristics. The amount of the charge control agent to be blended is appropriately in the range of 0.1 to 5% by weight based on the resin solid content containing the colorants.

The capsule-type toner obtained by the production method of the present invention has characteristics particularly suitable as a developer for a dry electrostatic latent image, and easily has a small particle size of about 6 to 8 μm (μm). It can be used as a next-generation high-resolution developer because it can provide a large-diameter toner.

In addition, a color toner having desired characteristics can be easily manufactured.

[0092]

EXAMPLES Next, the method for producing a capsule type toner according to the present invention will be described more specifically with reference to examples, examples and comparative examples. In the following, all parts and% are based on weight unless otherwise specified.

Reference Example 1 (Preparation Example of Water-Insoluble Resin) 200 mL of methyl ethyl ketone was placed in a reaction vessel purged with nitrogen.
A part was charged and the temperature was raised to 80 ° C. Where it reached the same temperature,
A mixture of 13.8 parts of methacrylic acid, 202 parts of styrene, 33 parts of 2-ethylhexyl methacrylate, 51.2 parts of methyl methacrylate and 3 parts of t-butylperoxy-2-ethylhexanoate. It was added dropwise over 2 hours.

After completion of dropping, stirring was continued for 2 hours,
Further, 1.5 parts of t-butylperoxy-2-ethylhexanoate was added. After continuing stirring at the same temperature for 3 hours, 250 parts of methyl ethyl ketone was added to obtain a water-insoluble resin. Hereinafter, this is abbreviated as A-1.

The content of acidic groups in 100 g of the resin solid content was 53.5 mg and the resin solid content was 40.0%.

Reference Example 2 (same as above) 200 ml of methyl ethyl ketone was placed in a reaction vessel purged with nitrogen.
Parts were charged and the temperature was raised to 80 ° C. Where it reached the same temperature,
4.6 parts of methacrylic acid, 209.3 parts of styrene, 33 parts of 2-ethylhexyl methacrylate, 53.1 parts of methyl methacrylate and t-butylperoxy-2-
A mixture of 3 parts of ethyl hexanoate was added dropwise over 2 hours.

Even after the completion of dropping, stirring was continued for 2 hours,
Further, 1.5 parts of t-butylperoxy-2-ethylhexanoate was added. After continuing stirring at the same temperature for 3 hours, 250 parts of methyl ethyl ketone was added to obtain a water-insoluble resin. Hereinafter, this is abbreviated as A-2.

The content of acidic groups in 100 g of the resin solid content was 17.8 mg and the resin solid content was 38.6%.

Reference Example 3 (Same as above) 300 ml of methyl ethyl ketone was placed in a reaction vessel purged with nitrogen.
Parts were charged and the temperature was raised to 80 ° C. Where it reached the same temperature,
A mixture of 23.6 parts of dimethylaminoethyl methacrylate, 240.4 parts of styrene, 36 parts of 2-ethylhexyl methacrylate and 3 parts of t-butylperoxy-2-ethylhexanoate was added over 2 hours. Was dropped.

After completion of dropping, stirring was continued for 2 hours, and 1.5 parts of t-butylperoxy-2-ethylhexanoate was further added. After continuing stirring at the same temperature for 3 hours, 150 parts of methyl ethyl ketone was added to obtain a water-insoluble resin. Hereinafter, this is abbreviated as A-3.

The content of the basic group in 100 g of the resin solid content was 40.0 mg and the resin solid content was 39.5%.

Example 1 600 parts of A-1 obtained in Reference Example 1 and "MA-10
0 "[Carbon Black manufactured by Mitsubishi Kasei Co., Ltd.] and 26.7 parts of it are predispersed with a homomixer, and then" Eiger Motor Mill M-250 "(product of Eiger USA) Therefore, the mixture was dispersed for 1 hour.

Next, 3.6 parts of "Neugen EA-130T" [polyethylene glycol nonylphenyl ether manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.] as dispersion stabilizers and an acidic group were added to the mixed dispersion. And 9.7 parts of triethylamine for addition to the mixture were added, and the mixture was stirred until the mixture became uniform. Then, deionized water was gradually added into the system at a dropping rate such that water was uniformly mixed. In addition, phase inversion emulsification was performed.

After the particles were formed, the organic solvents were removed by vacuum distillation, and then a 0.1 N hydrochloric acid aqueous solution was added until the pH of the particle dispersion became 6. The particles were then separated from the dispersion medium by filtration to obtain a wet cake of particles, which was washed several times with deionized water.

Finally, freeze-drying was carried out to obtain powder particles of carbon toner. The average particle size of the powder particles by a Coulter counter was 7.8 μm. Further, the powder particles were subjected to a charge amount measurement by a blow-off charge amount measuring device manufactured by Toshiba Corp.
It was micro coulomb / g.

Example 2 600 parts of A-1 obtained in Reference Example 1 and "MA-1"
26.7 parts of "00" was pre-dispersed with a homomixer, and then "Eiger Motor Mill M-250"
Therefore, the mixture was dispersed for 1 hour.

To this mixed dispersion, 6.0 parts of "Neugen EA-130T" as a dispersion stabilizer and 9.1 parts of triethylamine for neutralizing an acidic group were added,
Stirring was carried out until the mixture became uniform, and then deionized water was gradually added into the system at a dropping rate such that water was uniformly mixed to carry out phase inversion emulsification.

After the particles were formed, the organic solvents were removed by vacuum distillation, and then a 0.1N aqueous hydrochloric acid solution was added until the pH of the particle dispersion became 6. The particles were then separated from the dispersion medium by filtration to obtain a wet cake of particles, which was washed several times with deionized water.

Finally, freeze-drying was performed to obtain carbon toner powder particles. The average particle size of the powder particles by a Coulter counter was 5.8 μm. The powder particles were measured for their charge quantity by a blow-off charge quantity measuring device and found to be -32 micro coulombs / g.

Example 3 600 parts of A-2 obtained in Reference Example 2 and “MA-10
0 "and 25.7 parts were predispersed with a homomixer, and then" Eiger Motor Mill M-25
"0" was mixed and dispersed for 1 hour.

Next, to this mixed dispersion, as a dispersion stabilizer, an acid value of 260, a solid content of 40%, a weight average molecular weight of 8,000 and 100% of dimethylaminoethanol were used. 46.0 parts of the neutralized water-soluble acrylic resin and 4.1 parts of triethylamine for neutralizing the acidic groups were added, and the mixture was stirred until uniform, followed by deionized water addition. Then, phase inversion emulsification was carried out by gradually adding to the system at a dropping rate such that water was uniformly mixed.

After the particles are formed, the organic solvents are removed by vacuum distillation, and the particles are separated from the dispersion medium by filtration to obtain a wet cake of particles, which is washed several times with deionized water. Was repeated.

After that, until the pH reaches 6, it is adjusted to 0.1.
The neutralized acidic group is returned to the original acidic group by adding a specified hydrochloric acid aqueous solution, and then the hydrochloric acid salt is washed with deionized water, followed by freeze-drying to obtain a carbon toner powder. The particles were obtained.

The average particle size of the powder particles by a Coulter counter was 12.6 μm. The charge amount of the powder particles was measured by a blow-off charge amount measuring device and found to be -15 micro coulomb / g.

Example 4 600 parts of A-3 obtained in Reference Example 3 and “MA-10
2 "and 26.3 parts of" 0 "are pre-dispersed with a homomixer, and then" Eiger Motor Mill M-25
"0" was mixed and dispersed for 1 hour.

Then, 3.6 parts of "Neugen EA-130T" as a dispersion stabilizer was added to the mixed dispersion.
Add 4.3 parts of acetic acid to neutralize the basic groups,
Stirring was carried out until the mixture became uniform, and then deionized water was gradually added to the system at a dropping rate such that water was uniformly mixed to carry out phase inversion emulsification.

After the particles were formed, organic solvents were removed by vacuum distillation, and then a dimethylethanolamine aqueous solution was added until the pH of the particle dispersion became 6. After that, the particles are separated from the dispersion medium by filtration to obtain a wet cake of particles, which is washed with deionized water several times, filtered, and finally dried by freeze-drying to remove carbon. -Toner powder particles were obtained.

The average particle size of the powder particles by a Coulter counter was 11.4 μm. The powder particles were measured for their charge amount with a blow-off charge amount measuring device and found to have 23 micro coulombs /
It was g.

Example 5 600 parts of A-1 obtained in Reference Example 1 and “MA-10
0 "and 26.7 parts of them are pre-dispersed with a homomixer, and then" Eiger Motor Mill M-25
"0" was mixed and dispersed for 1 hour.

Next, to this mixed dispersion, 5.7 parts of sodium laurate as a dispersion stabilizer and 9.7 parts of triethylamine for neutralizing an acidic group were added, and the mixture was homogenized. Stirring was carried out, and then deionized water was gradually added in the system at a dropping rate such that water was uniformly mixed to carry out phase inversion emulsification.

After the particles were formed, the organic solvents were removed by distillation under reduced pressure, followed by washing with water three times, and then a 0.1 N hydrochloric acid aqueous solution was added until the pH of the particle dispersion became 6. The particles were then separated from the dispersion medium by filtration to obtain a wet cake of particles, which was washed several times with deionized water.

Finally, the product was dried by freeze-drying to obtain carbon toner powder particles. The average particle size of the powder particles by a Coulter counter was 6.2 μm. The powder particles were measured for charge quantity by a blow-off charge quantity measuring device and found to be -28 micro coulombs / g.

Comparative Example 1 600 parts of A-1 obtained in Reference Example 1 and "MA-10
0 "and 26.7 parts of them are pre-dispersed with a homomixer, and then" Eiger Motor Mill M-25
"0" was mixed and dispersed for 1 hour.

Then, to this mixed dispersion, the dispersion stabilizers were not added at all, and 13.0 parts of triethylamine was added, and the procedure of Example 1 was repeated. Phase inversion emulsification was performed. As a result, although particles were obtained, the particle size was as large as 50 microns or more,
Some of them were aggregated.

Comparative Example 2 600 parts of A-3 obtained in Reference Example 3 and “MA-10
2 "and 26.3 parts of" 0 "are pre-dispersed with a homomixer, and then" Eiger Motor Mill M-25
"0" was mixed and dispersed for 1 hour.

Then, to this mixed dispersion, the dispersion stabilizers were not added at all, and 5.7 parts of acetic acid was added. Phase inversion emulsification was performed. As a result, only aggregates were obtained, and no particles were obtained.

[0127]

According to the manufacturing method of the present invention, the dispersibility of the colorants is extremely excellent because the resin and the colorants are mixed and dispersed by the wet process in the first step. While maintaining this state, particles are manufactured by the second step.

At this time, the water-insoluble resin having a neutralized acidic group or basic group is subjected to phase inversion emulsification in combination with dispersion stabilizers. Therefore, the water-insoluble resin itself is used. It is not necessary to have self-emulsifying ability, and as a result, it becomes possible to reduce the amount of functional groups in the resin, and at the same time, charging characteristics suitable as a toner can be obtained.

At the same time, the amount of the dispersion stabilizers can be reduced, and the washing process of the dispersion stabilizers can be greatly simplified.

The production method of the present invention remarkably expands the production method of toner particles by the phase inversion emulsification method using a self-water-dispersible resin. Therefore, desired toner characteristics, that is, charging characteristics and fixing It is characterized in that it is easy to obtain fluidity and fluidity.

Claims (9)

[Claims] 1. A mixture of a water-insoluble resin having a neutralized acidic group or a neutralized basic group, a colorant, and an organic solvent in the presence of dispersion stabilizers. A method for producing a capsule type toner, which comprises dispersing particles in an aqueous medium to produce particles, and then separating the particles thus produced from the aqueous medium and drying. 2. A mixture of a water-insoluble resin having a neutralized acidic group or a neutralized basic group, a colorant, and an organic solvent in the presence of dispersion stabilizers. The neutralized acidic groups or neutralized basic groups described above are formed by a series of steps of dispersing in an aqueous medium to form particles, and then separating the particles thus formed from the aqueous medium and drying. A method for producing a capsule type toner, which comprises returning a part or all of the groups to acidic groups or basic groups. 3. A mixture of a water-insoluble resin having a neutralized acidic group or a neutralized basic group, a colorant, and an organic solvent in the presence of dispersion stabilizers, Dispersing a part or all of the above dispersion stabilizers by a series of steps of dispersing in an aqueous medium to form particles, and then separating the particles thus formed from the aqueous medium and drying. A method for producing a capsule-type toner, comprising: 4. The water-insoluble resin has a neutralized acidic group or neutralized basic group of 3 to 100 milligram equivalents per 100 g of resin solids.
The manufacturing method according to claim 1, 2 or 3. 5. The production method according to claim 1, 2 or 3, wherein the acidic group or the basic group is a carboxyl group or an amino group. 6. The amount of the dispersion stabilizers in the aqueous medium is in the range of 0.1 to 10 parts by weight based on 100 parts by weight of the solid content of the water-insoluble resin.
The manufacturing method according to 2 or 3. 7. The dispersion stabilizer described above is an anionic surfactant, a cationic surfactant, a nonionic surfactant or an amphoteric surfactant, 1.
The manufacturing method described in. 8. The production method according to claim 1, 2 or 3, wherein the dispersion stabilizer is an anionic water-soluble resin, a cationic water-soluble resin or a nonionic water-soluble resin. 9. The manufacturing method according to claim 1, wherein the water-insoluble resin is an acrylic resin, a styrene resin, a polyester resin, or a urethane resin.