JPH10293419A - Electrostatic charge image developing toner and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain toners which are uniformly fixed with charge control agents on the surface and have excellent electrostatic charge characteristics by composing specific thermoplastic resin regions uniformly dissolved or dispersed with the charge control agents to a submicron or below of approximately spherical particles fixed and molded on toner particle surfaces. SOLUTION: The thermoplastic resin regions which are uniformly dissolved or dispersed with the charge control agents to the submicron or below and have functional groups increased in hydrophilicity by neutralization consist of the approximately spherical particles fixed to the surfaces of the original toner particles. Namely, the charge control agents are completely coated with the resins in the thermoplastic resin regions and are fixed to the state of not exposing to the surfaces. The thermoplastic resins in the regions have the functional groups increased in the hydrophilicity by neutralization but are not neutralized and are, therefore, poor in the hydrophilicity and are excellent in moisture resistance. The respective thermoplastic resin region constituting the regions and the toner particles are so properly selected as to be melted by the energy given from outside and to be fixed on recording medium, such as paper.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a new and useful toner and a method for producing the same. More specifically,
The present invention contains a self-water dispersible resin and a colorant,
More particularly, the present invention relates to a toner used for developing an electrostatic latent image and a method of manufacturing the same.

[0002]

2. Description of the Related Art As a method for producing a toner for developing an electrostatic charge image,
A pulverization method as a dry method, and a polymerization method as a wet method,
There is a so-called phase inversion emulsification method described in JP-A-5-66600 and the like.

In general, a charge controlling agent is used in a toner for developing an electrostatic image to control charging characteristics such as charge amount, charging speed, stability over time, and environmental stability. In the conventional method, the toner is added to the toner binder resin by incorporating it into the particles in advance by dispersing the toner binder resin together with a colorant at the time of kneading. However, since the charge control agent of only the surface layer of the particles can contribute to its effect, such an addition method is very wasteful. Therefore, it is considered that a large charge characteristic improving effect can be obtained with a very small amount of addition of the charge control agent only on the surface of the toner particles.

[0004] At present, surface treatment with a charge control agent by mechanical dry addition or wet treatment is being studied. However, adverse effects such as desorption of the charge control agent and contamination by the charge control agent such as a carrier are considered. However, charging stability is practically insufficient, and an effective means has not yet been found as a surface treatment method of a toner with a charge control agent.

[0005]

That is, an object of the present invention is to provide a toner having excellent charge characteristics in which a charge control agent is uniformly fixed on the surface of toner particles, a pulverization method, a polymerization method, and a phase inversion emulsification method. In the toner obtained by, for example,
An object of the present invention is to provide a method for producing a toner having excellent charge characteristics by uniformly fixing a charge control agent on the surface of toner particles.

Further, the amount of the charge control agent used can be greatly reduced as compared with the related art, and therefore, the cost advantage over the current toner can be obtained. The toner according to the present invention exerts a very good effect in both one-component development and two-component development, and obtains a good image.

[0007]

Means for Solving the Problems Accordingly, the present inventors have:
Focusing on the problem to be solved by the invention as described above, as a result of intensive studies, as a toner particle structure,
A thermoplastic resin region (ii) having a functional group that increases hydrophilicity by neutralization, in which the charge control agent (F) is uniformly dissolved or dispersed in the submicron order, is fixedly formed on the surface of the toner particles (C). It has been found that a toner for developing an electrostatic image composed of substantially spherical particles solves the above-mentioned problems.

As one example of a method for obtaining a toner for developing an electrostatic image having such a particle structure, a self-water-dispersible resin or a water-soluble resin and an organic solvent of a charge controlling agent are added to a dispersion of toner particles (C). This problem can be solved by separately adding an aqueous dispersion having a particle size smaller than that of the toner particles obtained by phase inversion emulsification of the mixture so as to fix the dispersed particles on the surface of the toner particles. And completed the present invention.

That is, the present invention provides the following invention. The thermoplastic resin region (ii) having a functional group that increases hydrophilicity by neutralization, in which the charge control agent (F) is uniformly dissolved or dispersed to submicron or less, is composed of the resin (A) and the colorant (B). The toner for developing an electrostatic image (hereinafter, referred to as a first invention), which is fixed to the surface of the toner particles (C) and contains substantially spherical particles.

[0010] An aqueous dispersion (I) of particles (C) comprising a resin (A) and a colorant (B) as essential components, and a resin (D1) which can become a self-water-dispersible resin by neutralization. Self-water dispersible resin (D) obtained by neutralizing with neutralizing agent (E)
2) a mixture containing, as essential components, a charge control agent (F) and an organic solvent (G) that dissolves (D2), and / or
A water-soluble resin (H2) obtained by neutralizing a resin (H1) which can be a water-soluble resin by neutralization with a neutralizing agent (E), a charge controlling agent (F), and an organic solvent dissolving (H2) J) and a mixture obtained by subjecting the mixture to phase inversion emulsification in an aqueous medium, wherein the charge control agent (F) is dissolved or dispersed and contained in submicron or less particles (C). The aqueous dispersion (II) of particles having a small average particle diameter (D2) or (H2) is uniformly mixed, and a polar neutralizer (K) opposite to the neutralizer (E) is mixed. In addition, a method for producing a toner having a charge control agent fixed to the surface of toner particles, from which the liquid medium is removed and dried (hereinafter, referred to as a second invention).

[0011] The toner of the first invention is characterized by its particle structure. That is, a thermoplastic resin region (ii) having a functional group that increases hydrophilicity by neutralization, in which a charge control agent (F) is uniformly, dissolved or dispersed to a submicron or less, is fixed to the surface of toner original particles. I have. That is, the area (ii)
In the above, the charge control agent is completely covered with the resin and fixed without being exposed to the surface.

The charge controlling agent (F) is completely compatible with the thermoplastic resin forming the region (ii) and is uniformly dissolved, or is less than 1 μm (1000 nm) even if it is not dissolved (submicron or less). It is necessary that the particles are uniformly finely dispersed so as to be fine particles of

The thermoplastic resin in the above-mentioned region (ii) has a functional group that increases hydrophilicity by neutralization, but is not neutralized and thus has poor hydrophilicity and excellent moisture resistance. Each thermoplastic resin constituting the region (ii) and the particles (C) is appropriately selected such that it can be melted by externally applied energy and fixed on a recording medium such as paper.

The region (ii) is adhered (fixed) to such an extent that the corresponding toner particles (C) do not separate from the original toner particles due to the high affinity with the thermoplastic resin. The cross-sectional thickness of this region (ii) is preferably as thin as possible, and is usually 3 μm or less. This area (ii)
It may be formed on at least a part of the surface of the toner particles, and of course, the entire surface of the toner particles may be covered with this region (ii).

[0015] The toner particles of the present invention are substantially spherical. The substantially spherical shape includes, for example, a case of a perfect circular sphere, a case of an elliptical sphere, and a case of a circular sphere having an uneven surface. The degree of sphere can be defined by, for example, Wardel sphericity. As the toner particles of the present invention, it is preferable that the toner base particles (C) excluding the region (ii) have a Wader sphericity of ≧ 0.7.

In order to obtain the toner of the first invention, various production methods are conceivable. For example, as an example,
The manufacturing method of the second invention is mentioned.

In the second invention, the aqueous dispersion (I) of the toner particles (C) for fixing the particles containing the charge control agent is
Any material obtained by any method can be used,
It is preferable to use an aqueous dispersion of particles, such as obtained by a wet method such as a polymerization method or a phase inversion emulsification method.

That is, in this case, the self-water-dispersible resin (L2) obtained by neutralizing the resin (L1) which can become self-water-dispersible by neutralization with the neutralizing agent (N) in the particles (C).
And a colorant (B) as essential components, and if necessary, a phase inversion emulsification with an aqueous medium containing an organic solvent (M) dissolving (L2) or neutralization. Resin (L1) that can be self-water dispersible, and colorant (B)
Is obtained by subjecting a mixture containing an organic solvent (M) that dissolves (L1) as necessary as an essential component to phase inversion emulsification with an aqueous medium containing a neutralizing agent (N). The resin particles contain the agent (B).

The production method of the present invention is characterized by comprising an aqueous dispersion of resin particles containing a colorant, and a self-water-dispersible resin and / or a water-soluble resin containing a charge control agent, which is separately prepared. By mixing an aqueous dispersion of particles smaller than the resin particles and precipitating resin fine particles containing the charge control agent on the surface of the resin particles, (D1)
(H1) functions as a fixing resin, and the charge control agent is firmly fixed to the surface of the toner particles. By such means, the effect of the charge control agent is effectively exhibited, and the charging characteristics are improved.

Further, the charge control agent is selected from resins (D1) and (H
Since the toner particles are firmly fixed to the toner particles according to 1), peeling of the charge control agent from the toner at the time of friction with the carrier or the like is eliminated, and carrier contamination due to these components does not occur.

More specifically, the charge control agent (F) is fixed to the surface of the colored particles of the main body while being completely covered and included in the resin (D1) and / or the resin (H1). Therefore, there is no surface exposure of the charge control agent. Moreover, the resin (D1) and the resin (H1) have high fixing strength to the colored particles.

In the toner of the present invention, stable chargeability can be obtained without causing charge inhibition due to carrier contamination by the charge control agent or peeling of the charge control agent due to friction during operation of the developing machine.

Before describing the steps of the present invention, each component used in the present invention will be described. The resin (A) that can be used in the present invention may be any resin that can be used as a toner binder resin. Among them, particularly the self-water dispersible resin will be described below. The resins (D1) and (L1) and the self-water-dispersible resins (D2) and (L2) that can be converted into a self-water-dispersible resin used in the present invention will be described.

In the present invention, the resin capable of becoming self-water dispersible by neutralization is defined as a functional group contained in a molecule capable of increasing hydrophilicity due to neutralization, which is used as an emulsifier or dispersant under the action of an aqueous medium. A resin having the ability to form a stable aqueous dispersion or aqueous solution without substantially using a stabilizer. The self-water-dispersible resin is a resin that can become self-water-dispersible by neutralization (a resin having a functional group in its molecular chain whose hydrophilicity can be increased by anionic or cationic neutralization). This is a resin in which the functionality is neutralized with a base if it is cationic and the acid is used if it is cationic, so that the functional group has a salt structure to increase the hydrophilicity.

The degree of hydrophilicity can be appropriately adjusted by the degree of neutralization (neutralization rate). The degree of hydrophilicity at this time must be such that the resin itself can be dispersed in water. When such a self-water-dispersible resin is mixed with an aqueous medium, phase inversion emulsification occurs to generate particles.

The hydrophilicity of a resin containing an acid group or a basic group, which can become self-water dispersible by neutralization, is determined by the amount of the functional group or the amount of neutralization (neutralization rate) which can increase the hydrophilicity by neutralization. Can be controlled by A self-water-dispersible resin can be obtained by adjusting the degree of neutralization using a resin that can become water-soluble when completely neutralized.

Further, the particle size at the time of dispersion in phase inversion emulsification is determined by the hydrophilicity. That is, an arbitrary particle size can be easily obtained by controlling the neutralization ratio.

The functional groups of the resins (D1) and (L1) which can increase hydrophilicity by neutralization in the resins include, for example, carboxyl group, phosphoric acid group, sulfone group, and sulfuric acid group in the case of anionic type. A tertiary amino group.

For example, when the self-water-dispersible resin (D2) is an anionic type, the resin contains a neutralized acid group as described above. That is, the self-water dispersible resin (D
2) If the water-soluble resin (L2) is a hydrophilic group of an anionic type (sex), the resin contains a neutralized acid group as described above.

The amount of the neutralized functional group such as an acid group or a basic group (neutralization amount, neutralization ratio) required for the resin to exhibit a self-water dispersing function depends on the composition, molecular weight, structure, etc. The degree of neutralization differs for each resin because the hydrophilicity of the resin itself varies depending on the resin.
It is within the range of 0 to 400 mg equivalent.

The salt structure of the neutralized functional group is such that the functional group in the resin (D1) or (L1), which can become self-water dispersible by neutralization, is neutralized with the neutralizing agent (E) or (N). The effect is the same regardless of whether the resin is obtained by neutralization or is already present in the resin as a salt structure.

In carrying out the present invention, when it is necessary to convert a part or all of the resins (D1) and (L1) into self-water dispersible resins (D2) and (L2), By neutralizing a part or all of the functional groups contained in the resins (D1) and (L1), whose hydrophilicity can be increased by neutralization, with neutralizing agents (E, N) having opposite polarities thereto. It can be adjusted appropriately.

However, in the present invention, the resin (D
In (1) and (L1), both polarities may be the same or opposite. Therefore, the neutralizing agents (E) and (N) are not necessarily of the same polarity.

Examples of the resin capable of becoming self-water-dispersible by neutralization and the self-water-dispersible resin include, for example, acrylic resins,
There are polyester resin, polyurethane resin, epoxy resin, alkyd resin and the like. Acrylic resins, in particular, styrene / acrylate copolymer resins, in which the balance between powder fluidity and fixability as a toner can be relatively easily obtained, are preferred.

Next, an acrylic resin will be described as an example. As the anionic acrylic resin that can become self-water dispersible or water-soluble by the neutralization, the above-described acid group, or an acrylic polymerizable vinyl monomer containing a basic group, Those obtained by radically polymerizing a polymerizable vinyl monomer other than the acid-containing polymerizable vinyl monomer in the presence of a radical initiator can be used. The polymerization reaction for obtaining it can be suitably used in solution polymerization, suspension and emulsion polymerization.

Examples of such acid group-containing acrylic polymerizable monomers include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, monobutyl itaconate, and monobutyl maleate.
Examples of the basic group-containing acrylic polymerizable monomers include acrylate derivatives such as dimethylaminoethyl, diethylaminoethyl, dibutylaminoethyl, and N-ethyl-N-phenylaminoethyl, and methacrylate derivatives.

Examples of the polymerizable monomers other than the acid group or basic group-containing polymerizable monomers include styrene-based monomers (aromatic vinyl monomers) such as styrene,
Examples include vinyltoluene, 2-methylstyrene, t-butylstyrene or chlorostyrene.

The acrylates include, for example, methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, isoamyl acrylate, n-hexyl acrylate, acryl 2-ethylhexyl acrylate, n-octyl acrylate, decyl acrylate or dodecyl acrylate, 2-chloroethyl acrylate,
Examples include phenyl acrylate and methyl alpha-chloroacrylate.

Examples of the methacrylate include methyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, and n-methacrylic acid. Octyl, decyl methacrylate, dodecyl methacrylate, 2-chloroethyl methacrylate, phenyl methacrylate, and alpha-methyl methacrylate.

Further, acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone. Examples thereof include vinyl ketones, N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, N-vinyl compounds such as N-vinylpyrrolidone, and the like.

For obtaining a resin which can become self-water dispersible by neutralization or a self-water dispersible resin, in the case of solution polymerization, a general-purpose organic solvent can be used. Specifically, various aromatic hydrocarbons such as toluene, xylene or benzene; various alcohols such as methanol, ethanol, propanol or butanol;
Various ether alcohols such as cellosolve or carbitol; various ketones such as acetone, methyl ethyl ketone or methyl isobutyl ketone; various esters such as ethyl acetate or butyl acetate; or various ethers such as butyl cellosolve acetate So-called inert solvents such as esters.

As the polymerization initiator to be used, various commonly used organic peroxide-based initiators and azo-based initiators can be used. Specifically, for example, peroxides such as benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, sodium persulfate and ammonium persulfate, and azo-based compounds such as azobisisobutyronitrile and azobisisovaleronitrile Compounds.

As the self-water dispersible acrylic resin, for example, those having a weight average molecular weight of 1,000 to 300,000 are preferably used. Further, the glass transition temperature is 30 to 12
It is preferable to use one at 0 ° C.

Next, the resin (H1) which can be converted into a water-soluble resin by neutralization and the water-soluble resin (H2) will be described. In the present invention, a resin (H
1) is a resin having the ability to become water-soluble by the action of a functional group in the molecule that can increase hydrophilicity by neutralization. Further, the water-soluble resin (H
2) is to neutralize a resin which can become a water-soluble resin by neutralization, thereby neutralizing a functional group capable of increasing hydrophilicity due to anionic or cationic neutralization contained in the resin, thereby forming a salt. It is a structure that has increased hydrophilicity and becomes water-soluble.

The water-soluble resin (H2) in the present invention has a higher hydrophilicity than the self-water-dispersible resin (D2). Although it is difficult to clearly distinguish between water solubility and self-water dispersibility, those that become transparent when dispersed in water are judged to be water-soluble and those that become cloudy are judged to be self-water dispersible.

The functional group which can increase hydrophilicity by neutralization is
It contains the same ones as those contained in the resin that can become a self-water dispersible resin by neutralization.

The weight average molecular weight is 1,000 to 30,000
A resin having 0, preferably 2000 to 150,000 is preferred. Further, a resin having an acid value of 20 to 200, preferably 30 to 120 is preferable.

[0048] Resins that can become water-soluble resins by neutralization are also:
The same kind of resin as the resin that can become a self-water dispersible resin by neutralization can be used, and can be obtained by the same synthesis method.

(H1) used in the present invention is not necessarily (L
It is not necessary to have the same polarity as in 1). (H2) may be a single resin, a mixture of two or more resins, or a mixture with (D2). However, in these cases, the same polarity is used.

The neutralizing agents (E), (N), and
(K) will be described. The neutralizing agent (E) neutralizes an acid group or a basic group in the resin (D1) that can become self-water dispersible by neutralization and the resin (H1) that can become a water-soluble resin by neutralization, and The water-dispersible resin (D2) and the water-soluble resin (H2) are used, and the neutralizing agent (K) is (D2)
The salt structure of (H2) is returned to the original functional group, and (D1)
Used to return to (H1). Therefore, (E)
It is necessary to use one having the polarity opposite to that of (K). For example, if (D1) contains a carboxyl group, a base is used for (E) to form an anionic self-water dispersible resin, and an acid is used for (K).

The neutralizing agent (N) neutralizes an acid group or a basic group in the resin (L1), which can become self-water dispersible by neutralization, to form a self-water-dispersible resin (L2). is there.

Since (D1), (H1) and (L1) are not necessarily of the same polarity, (E) and (N) are not necessarily neutralizers of the same polarity.

The neutralizing agents (E), (N) and (K) are not particularly limited, but examples of basic ones include sodium hydroxide, potassium hydroxide, lithium hydroxide and ammonia. Inorganic alkali, alkanolamines such as monoethanolamine and diethanolamine, secondary amines such as dimethylamine and diethylamine, tertiary amines such as triethylamine, hydrazine and the like. And organic acids such as oxalic acid, formic acid, acetic acid, succinic acid, p-toluenesulfonic acid and the like.

In the present invention, the following combinations are exemplified.

[0055]

[Table 1]

In Table 1, N means that the resin has negative chargeability, and P means that the resin has positive chargeability. The resin (A) in the particles (C) and / or the resin for fixing the charge control agent (F) to the particles (C) are paired. (N) means that the neutralizing agent is an acid. Similarly, (P) means that the neutralizing agent is a base. O is
It means nonpolar, and typically includes those obtained by a polymerization method.

When finally obtaining a negatively charged toner, the combination of the above 1 is more effective than the above 4 in reducing the various characteristics and / or the process itself of the finally obtained toner for developing an electrostatic charge image and the process conditions. Is more preferable in that it can be more relaxed.

That is, when a negatively charged toner is obtained by carrying out the second invention, if the other steps are common, the particles (C) containing the resin (A) and the colorant (B) as essential components The aqueous dispersion (I) of the particles (C) comprising the non-polar resin obtained by a polymerization method and the colorant (B) as essential components as the aqueous dispersion (I) of (a). If
Necessary components comprising a self-water-dispersible resin obtained by neutralizing a resin capable of becoming self-water-dispersible by neutralization having an anionic functional group (acid group) with a base and a colorant (B) as essential components It is preferable to use an aqueous dispersion of resin particles containing a colorant (B), which is obtained by subjecting a mixture containing an organic solvent that dissolves the self-water dispersible resin to phase inversion emulsification with an aqueous medium in accordance with the above. ,preferable.

In obtaining a positively charged toner, in terms of odor and the like, it is possible to use a positively charged resin as the resin (A) in the particles (C) and perform the same combination as described above. Not preferred.

The neutralization of the resins (D1) and (L1), which can become self-water dispersible by neutralization, and the resin (H1), which can become a water-soluble resin by neutralization, is performed by mixing with an aqueous medium during phase inversion emulsification. Or immediately before mixing with the aqueous medium during the phase inversion step.

As the colorant (B) in the present invention, a general-purpose colorant can be used. Specifically, for example, carbon black, magnetic powder, aniline blue, calcoil blue, chrome yellow, ultramarine blue, Dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengalara, C. I. Pigment Red 122, C.I. I. Pigment Yellow 97,
C. I. Pigment Blue 15, iron trioxide, iron sesquioxide, iron powder, zinc oxide, selenium and the like.
Species or a combination of two or more can be used.

The amount of the colorant (B) used in the present invention is usually selected from the range of 3 to 15 parts by weight per 100 parts by weight of the resin solids. The solids content of the mixture is usually 2
It is adjusted within the range of 0 to 80% by weight.

In the present invention, general negative and positive charge control agents (F) include metal-containing azo compounds, metal compounds of salicylic acid derivatives, nigrosine, quaternary ammonium salt compounds, and metal-free resin-based charge control agents. Charge control agents can be used. In addition, a conductive coloring agent or the like can be used as the charge control agent. However, resin (D
When obtaining a mixture of (1), (D2), or (H1) or (H2) in an organic solvent, particles of (F) are as finely dispersed as possible by means such as mechanical pulverization. Is preferred.

In the thermoplastic resin, particles (D2) or particles (H2) constituting the region (ii), the particles are dissolved so as to be at the molecular level, or fine dispersion when they cannot be dissolved is less than 1 μm. , More preferably 500 nm
Less than.

(F) can be dissolved in an organic solvent and the resin (D
It is more preferable that (1), (D2), or (H1), (H2) and the organic solvent (G), (J) can be dissolved uniformly. However, when this mixture is subjected to phase inversion emulsification in water, it is not suitable for the case where only the charge control agent crystallizes or separates from the resin. Also, the active ingredient is water-soluble,
Those which become water-soluble when neutralized with an acid or a base undesirably elute into an aqueous medium.

For 100 parts by weight of the solid content of the particles (C),
0.001 to 5 parts by weight of the charge control agent (F) is used. Conversely, the amount of the charge control agent added to the toner is 0.1.
The range of 001% by weight to 5% by weight, preferably 0.005 to 4% by weight is preferred.

In the present invention, in the particles containing the charge control agent, the resin layer covering the charge control agent is extremely thin. Therefore, after the particles are fixed to the surface of the particle (C), in the region (ii), the charge control agent is not exposed to the surface but exists very close to the surface. For example, even with a very small amount of less than 0.1% by weight based on the particle (C), sufficient charging characteristics can be obtained.

In the present invention, the organic solvents (G), (J),
(M) is a colorant or charge control agent and resin (D, H,
When the mixture of L) is obtained, it can be used as needed. The organic solvent (G) comprises (D1) and (D2)
(J) is (H1) and (H2), (M) is (L1)
A general-purpose organic solvent that dissolves (L2) is used.
For example, toluene, xylene, aromatic hydrocarbon solvents such as benzene, methyl ethyl ketone, ketone solvents such as methyl isobutyl ketone, carbon tetrachloride, trichloromethane,
An organic solvent having relatively high hydrophobicity, such as a halogen-based solvent such as dichloromethane, is used. In this case, for example, the combined use of a water-soluble or partially water-soluble organic solvent such as acetone, butanol, or isopropyl alcohol facilitates the generation of particles in phase inversion emulsification.

Preferably, the use of so-called low boiling solvents, such as acetone, methyl ethyl ketone or ethyl acetate, which can be easily removed, is suitable.

As other constituent components (additive components) that can be used in the present invention, various auxiliaries such as a release agent may be mentioned, and may be appropriately selected according to the purpose and conditions of use. Can be used.

Examples of the auxiliary agent include waxes such as polyethylene wax, polypropylene wax and paraffin wax, metal soaps and lubricants such as zinc stearate.

Next, the steps of the manufacturing method of the present invention will be described. The present invention can be roughly divided into four steps. That is, a step (1) of obtaining an aqueous dispersion (I) of resin particles containing a resin and a colorant as essential components, and a self-water-dispersible resin and / or a water-soluble resin smaller than the resin particles containing a charge controlling agent. Aqueous Dispersion of Particles of Resin Resin (I
(2) a step of separately preparing I), and (3) a step of uniformly mixing (I) and (II) to precipitate resin fine particles containing a charge control agent on the surface of the resin particles. Thereafter, the liquid medium is removed and dried to obtain a toner powder (4).
It is.

Here, the aqueous dispersion (II) in the step (2) is typically smaller than the resin particles comprising a self-water dispersible resin and / or a water-soluble resin containing a charge control agent. An aqueous dispersion of small particles.

Of course, the steps (1) and (2) may be performed first or simultaneously. The description will be given for each process.

Step (1) is a step for obtaining an aqueous dispersion of particles containing a resin and a colorant as essential components.

The particles may be obtained by any method as described above. In some cases, a dispersion stabilizer or the like can be used to disperse the particles in an aqueous medium. In particular, when a particle obtained as an aqueous dispersion by a wet method such as a polymerization method or a phase inversion emulsification method is used, it is preferable in that the step of dispersing the particles in an aqueous medium can be omitted.

When the particles (C) obtained by the phase inversion emulsification method are used, this step is carried out by neutralizing the resin (L1) which can become self-water dispersible by neutralization with the neutralizing agent (N). A phase inversion of a mixture containing an organic solvent (M) that dissolves (L2) as necessary, which contains the dispersible resin (L2) and the colorant (B) as essential components, is performed by using an aqueous medium. Or resin capable of becoming self-water dispersible by neutralization (L1)
And a colorant (B) as essential components and, if necessary, a mixture containing an organic solvent (M) that dissolves (L1) is subjected to phase inversion emulsification with an aqueous medium containing a neutralizing agent (N). Thus, a dispersion (I) of the particles (C) is obtained.

In this case, first, for example, the resin (L2) and the colorant (B) are mixed and dispersed with an organic solvent (M), if necessary, by a known and conventional means to prepare a mixture. . For example, known and commonly used means such as a ball mill, a sand mill, and a motor mill can be employed.

In order to obtain the resin (L2), the resin (L1), which can become self-water dispersible by neutralization, and a neutralizing agent (N) may be mixed and neutralized.

A mixture containing the resin (L1), which can become self-water dispersible by neutralization, and the coloring agent (B) as essential components and, if necessary, an organic solvent (M) can also be prepared.

In this case, as the aqueous medium used for the phase inversion emulsification, an aqueous medium containing an amount of the neutralizing agent (N) necessary to make the resin (L1) self-dispersible in water is used.

In the phase inversion emulsification, the phase inversion emulsification may be performed by adding the corresponding aqueous medium to the mixture, or the phase inversion emulsification may be performed by adding the mixture to the corresponding aqueous medium. Good.

In any case, the mixture is phase-inverted and emulsified in the corresponding aqueous medium to obtain particles (C).
The aqueous dispersion (I) is obtained. The particles (C) in the dispersion (I) are composed of a self-water dispersible resin (L
2) Resin (L1) that can become a self-water-dispersible resin by neutralization using a neutralizing agent having a polarity opposite to that of (N) even if it is left
It may be converted to.

The above (I) may be obtained by removing the organic solvent (M) from the aqueous dispersion after the phase inversion emulsification. Also,
(I) may be one obtained by removing the organic solvent (M) from the aqueous dispersion after phase inversion emulsification, filtering (C), washing, etc., and then redispersing in an aqueous medium.

In the step (1), the average particle diameter is usually 1 to 1
An aqueous dispersion (I) containing 5 μm particles (C) is obtained.

In the step (2), the self-water-dispersible resin (D2) obtained by neutralizing the resin (D1) which can be a self-water-dispersible resin by neutralization with the neutralizing agent (E), and the charge control agent ( A mixture containing an organic solvent (G) that dissolves (D2) if necessary, and / or a resin (H1) that can be converted into a water-soluble resin by neutralization with a neutralizing agent (E) A mixture containing, as essential components, a water-soluble resin (H2) obtained by neutralization with water and a charge control agent (F) and, if necessary, an organic solvent (J) that dissolves (H2), is mixed with an aqueous medium. An aqueous dispersion (I) containing particles having a smaller average particle diameter than the particles (C), containing the charge control agent (F) and obtained by phase inversion emulsification
This is the step of obtaining I).

The mixture of (D2) and / or (H2) and the charge controlling agent (F) can be obtained by known and common means, similarly to the mixture in step (1). Further, if (F) is soluble in an organic solvent, for example, the organic solvent solution of (F) and (D)
2) may be mixed.

The charge control agent (F) and the resin (D2), (H
The ratio of 2) to the resin solid content is preferably 1 to 80% by weight, and more preferably 3 to 60% by weight.

(D1) used in step (2) is (L1)
May be the same resin or different resins. Further, a mixture of a plurality of resins may be used. (H1) may be the same resin as (D1), and may be the same resin or a different resin, or a mixture of a plurality of different resins.
Further, a mixture of (D2) and (H2) may be used.

The aqueous dispersion (II) is obtained by the same operation as in the step (1) (I). The average particle size of the dispersed particles (II) needs to be smaller than that of the particles (C), and is preferably 0.01 to 5 μm, and more preferably 0.03 to 3 μm.

(II) may be obtained by removing the organic solvents (G), (J) and the like from the aqueous dispersion after phase inversion emulsification.

In the step (3), (I) and (II) obtained in the steps (1) and (2) are uniformly mixed.
A neutralizing agent (K) having a polarity opposite to that of the neutralizing agent (E) used in the step (2) is added so that at least a part of the salt-forming portion of each resin component contained in the mixture is neutralized. This is a step of returning to a functional group in a non-neutralized state (unneutralized state), and by performing such treatment, the contained charge control agent (F) together with the resin (D2) and / or the resin (H2) It is deposited on the surface of the particles (C) containing the colorant (B). At this time, these are firmly fixed to the surface of the particles (C).

When a typical aqueous dispersion as described above in step (2) is used as (II), what is fixed on the surface of the particles (C) is the charge control agent (F). The resulting resin (D2) and / or resin (H2).

This is because the hydrophilic structure of the resin itself is reduced by returning the salt structure of the hydrophilic portion of the resin (D2) or the resin (H2) to the original hydrophilic group having lower hydrophilicity. This is the principle of acid precipitation and salt precipitation that precipitate on the particle surface.

The amount of the solid in the dispersion (II) obtained in the step (2) added to the aqueous dispersion of the particles (C) is 0.05 to 20% by weight based on the solid content of the particles (C). %, Usually 0.
05 to 10% by weight, preferably 0.1 to 10% by weight, more preferably 0.1 to 6% by weight, most preferably 0.1 to 6% by weight.
~ 2 weights.

The precipitation of the dispersion by neutralization with a neutralizing agent (K) is generally carried out with stirring.

The amount of the neutralizing agent (K) used is such that the resin (D2) or resin (H
Any amount may be used as long as it is necessary to precipitate 2). Resin (D
2) is a resin which does not disperse in water as it is, becomes an original resin which can become self-water dispersible by neutralization, or
The amount to be used is selected so that the resin (H2) becomes a poorly water-soluble resin as it is, and becomes the original resin which can be made water-soluble by neutralization.

In the step (4), a liquid medium is removed from the mixture containing the particles (C) having the charge control agent adhered to the surface obtained in the step (3) and dried to obtain a powder toner. is there.

The toner particles in the liquid mixture are separated from the liquid medium by an operation such as filtration. At this time, a trace amount of salt generated in the neutralization treatment in the step (3) is easily removed. A washing step is not particularly necessary.

The toner particles removed and separated from the liquid medium are as follows:
Dry to obtain a toner powder. This drying can be performed by any known and commonly used method. For example, hot air drying may be performed at a temperature at which the toner particles do not fuse or aggregate, or a freeze drying method. There is also a method of simultaneously separating and drying toner particles from an aqueous medium using a spray dryer or the like.

In the production method of the second invention, the charge control agent (F) dispersed in the particles (D2) or the particles (H2) needs to be on the order of submicrons. Use of a large charge control agent (F) does not mean that the above-mentioned method for producing a toner cannot be immediately performed.

As the particle size of the toner powder comprising the toner particles used in the present invention, any size can be selected within a practical level as a toner. From the matching property with the current machine, the volume average particle diameter is 3 ~ 15μ
m, preferably in the range of 4 to 12 μm.

The toner obtained by the production method of the present invention can be used as a non-magnetic one-component toner or a magnetic one-component toner.
Also, by combining with a carrier, it can be used as a two-component developer, and a high quality image can be obtained by developing good charging characteristics.

As the carrier, any known and commonly used carriers can be used. For example, iron, nickel, copper, zinc,
Metals such as cobalt, manganese, chromium, and rare earths, and alloys or oxides thereof, and powders of surface-treated glass and silica can be used. Of course, resin-coated carriers such as acrylic resin-coated carriers, fluororesin-coated carriers, and silicone resin-coated carriers can also be used. As the carrier, for example, a carrier of about 20 to 200 microns is used.

[0105]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention includes the following embodiments. 1. The thermoplastic resin region (ii) having a functional group that increases hydrophilicity by neutralization, in which the charge control agent (F) is uniformly dissolved or dispersed to submicron or less, forms the resin (A) and the colorant (B). A toner for developing an electrostatic charge image, wherein the toner is fixed to at least a part of the surface of the toner particles (C) as an essential component and is substantially spherical particles.

2. Aqueous dispersion liquid (I) of particles (C) comprising resin (A) and colorant (B) as essential components
And a resin (D
A self-dispersible resin (D2) obtained by neutralizing 1) with a neutralizing agent (E) and a charge controlling agent (F) as essential components.
If necessary, a mixture containing an organic solvent (G) that dissolves (D2) and / or a water solution obtained by neutralizing a resin (H1) that can be a water-soluble resin by neutralization with a neutralizing agent (E). Organic solvent (J) containing, as essential components, a hydrophilic resin (H2) and a charge control agent (F), and dissolving (H2) as required
Having a smaller average particle diameter than the particles (C) in which the charge control agent (F) is dissolved or dispersed and encapsulated, which is obtained by phase-inversion emulsification of a mixture containing
2) and / or an aqueous dispersion (II) of particles consisting of (H2) are homogeneously mixed, and the neutralizing agent (E) and the neutralizing agent (K) having the opposite polarity are added. A method for producing a toner in which a charge control agent is fixed to the surface of toner particles, wherein the liquid medium is removed and dried.

3. A self-water-dispersible resin (L2) obtained by neutralizing a resin (L1) whose particles (C) can be self-water-dispersible by neutralization with a neutralizing agent (N), and a colorant (B) A resin (L1) which can be made self-water dispersible by subjecting a mixture containing an organic solvent (M) that dissolves (L2) as an essential component, if necessary, to phase inversion emulsification in an aqueous medium or neutralization. ) And a coloring material (B) as essential components and, if necessary, a mixture containing an organic solvent (M) that dissolves (L1) is subjected to phase inversion emulsification in an aqueous medium containing a neutralizing agent (N). 3. The toner and the production method according to the above item 1 or 2, wherein the particles are particles containing the colorant (B) obtained by the method.

4. 4. The toner according to the above 1, 2 or 3, wherein the self-water-dispersible resin (D2) and the water-soluble resin (H2) have an anionic hydrophilic group.

5. 5. The toner and the production method according to the above item 4, wherein the anionic hydrophilic group is a carboxyl group.

6. 6. The toner and method according to the above 1, 2, 3, 4 or 5, wherein the charge control agent (F) is used in an amount of 0.001 to 5 parts by weight per 100 parts by weight of the solid content of the particles (C).

7. (D1), (H1), (L1)
Is selected from the group consisting of a polyester resin, a polyurethane resin, an epoxy resin, and an acrylic / styrene-based resin, and the toner according to the above item 1, 2, 3, 4, 5, 6, or 7.

[0112]

Next, the present invention will be described more specifically with reference examples, examples and comparative examples. In the following, all parts and percentages are by weight unless otherwise specified.

Reference Example 1 [Preparation example of resin capable of becoming anionic self-water dispersible by neutralization] 650 parts of methyl ethyl ketone was charged into a reactor and heated to 80 ° C. The mixture in the proportions indicated below was then added dropwise over a period of about 2 hours. Meanwhile, the reaction was performed under a nitrogen stream.

Acrylic acid 77 parts Styrene 600 parts 2-Ethylhexyl acrylate 143 parts Methyl methacrylate 180 parts "Perbutyl O" (manufactured by NOF Corporation) 8 parts Methyl ethyl ketone 20 parts

Four hours after the completion of the dropwise addition of the above mixture,
2 parts of “perbutyl O” were added to the reaction solution,
Then, every 4 hours, 2 parts of "Perbutyl O" were added and the reaction was maintained at 80 ° C. for 24 hours. After completion of the reaction, the mixture was diluted with methyl ethyl ketone so that the resin solid content was 50%, and the weight average molecular weight was 52,000.
0 was obtained. The acid value of the resin was 60 and the glass transition temperature was 70 ° C.

Example 1 To 700 parts of the resin obtained in Reference Example 1 and having a nonvolatile content adjusted to 50%, 38 parts of carbon black [basic carbon black manufactured by Cabot Corporation, USA] was used. .8 parts were added and mixed for 1 hour by "Eiger Motor Mill M-250" (Eiger Japan K.K.). Hereinafter, this is abbreviated as mixture (M-1).

Then, 1.5 parts of triethylamine and 13 parts of isopropyl alcohol were added to 100 parts of the mixture (M-1) [where the resin (A) became a self-water dispersible resin. ], While stirring at 350 rpm using a three-one motor,
0 parts was added dropwise at a rate of 20 ml / min to perform phase inversion emulsification.

Subsequently, the organic solvent was removed from the resulting aqueous medium dispersion by distillation under reduced pressure to obtain an aqueous dispersion (I-1). The average particle size of the self-water-dispersible resin particles containing carbon black particles in the aqueous dispersion obtained here was 8.3 μm as measured by a Coulter Multisizer 2.

To 200 parts of the resin (A) having a non-volatile content adjusted to 50% obtained in Reference Example 1, 11 parts of Bontron S-34 (a negative charge control agent manufactured by Orient Chemical Co.) was added. .1 part was added and mixed for 1 hour with an Eiger motor mill M-250. Hereinafter, this is referred to as a mixture (M-2).

Next, 20 parts of a 1N aqueous solution of sodium hydroxide was added to 100 parts of the mixture (M-2) [where the resin (A) became a self-water dispersible resin. ], Using a three-one motor, 350 rpm
While stirring, 200 parts of water was added to this at 20 ml / m.
The mixture was added dropwise at a rate of in to perform phase inversion emulsification.

Subsequently, the organic solvent was removed from the resulting aqueous medium dispersion by distillation under reduced pressure to obtain an aqueous dispersion (II-1). The average particle size of the self-water-dispersible resin particles containing the charge control agent in the obtained aqueous dispersion was measured by a CHDF particle size distribution measuring system (manufactured by CHDF, USA), and as a result, was 50 nm. .

The solid content of the aqueous dispersion (II-1) was 0.5% by weight based on the solid content (toner) of the aqueous dispersion (I-1) (toner). The aqueous dispersion (II-1) in an amount of 0.05% by weight was uniformly mixed and adjusted with distilled water so that the total solid content was 20%. In this mixture, under stirring,
A 0.1N hydrochloric acid aqueous solution was dropped at a rate of 4 ml / min until the pH of the solution became 2, and a resin containing a charge controlling agent and capable of becoming self-water dispersible by neutralization was fixed to the toner surface.

Next, the liquid medium was filtered from the mixture, the wet cake was washed with water, and the wet cake was freeze-dried, so that the surface of a resin-treated surface having a volume average particle diameter of 8.4 μm was charged with a charge controlling agent. A powder of fixed toner particles was obtained. 0.5% silica R972 (manufactured by Nippon Aerosil Co., Ltd.) was added to the toner particles using a Henschel mixer.
An externally added toner (A) was prepared.

Example 2 240 g of styrene 60 g of butyl acrylate 60 g of ethylene glycol methacrylate 3 g 6 g of azobisisobutyronitrile 3 g of dodecyl mercaptan 3 g of carbon black 15 g [basic carbon black manufactured by Cabot Corporation, USA] 3 g of biscol 550P [Polyprene wax manufactured by Sanyo Chemical Industries, Ltd.]

The above mixture was dispersed by TK Robomix (Homomixer manufactured by Tokushu Kika Kogyo Co., Ltd.), and 1500 g of ion-exchanged water in which 18 parts of sodium polyacrylate was dissolved.
Was added and dispersed and suspended. This mixed solution was placed in a flask equipped with a Faudler blade, and subjected to suspension polymerization at 80 ° C. for 10 hours under a nitrogen stream to prepare an aqueous dispersion of resin particles containing a colorant. The average particle size of the obtained resin particles was measured by Coulter Multisizer 2 and found to be 8.0.
μm.

The washing operation of filtering the aqueous dispersion of resin particles and dispersing it again in water was repeated several times to obtain an aqueous dispersion (I-2). Aqueous dispersion (I-2) and (I-
The amount by which the solid content of the aqueous dispersion (II-1) obtained in Example 1 is 0.5% by weight (the amount of the charge control agent added to the resin particles is 0.05% by weight) based on the solid content of 2). The aqueous dispersion (II-1) was uniformly mixed, and adjusted with distilled water so that the total solid content was 20%.

Under stirring, a 0.1N aqueous hydrochloric acid solution was added dropwise at a rate of 4 ml / min until the pH of the solution became 2, and the mixture was self-aqueous dispersed by neutralization containing a charge controlling agent. Resin which could become hydrophilic was fixed on the toner surface.

Next, the liquid medium was filtered from the mixture, the wet cake was washed with water, and the wet cake was freeze-dried, so that the surface of the resin-treated surface having a volume average particle diameter of 8.2 μm was charged with a charge controlling agent. A powder of fixed toner particles was obtained. 0.5% silica R972 (manufactured by Nippon Aerosil Co., Ltd.) was added to the toner particles using a Henschel mixer.
An externally added toner (B) was prepared.

Example 3 To 200 parts of the resin (A) having a nonvolatile content adjusted to 50% obtained in Reference Example 1, Bontron N
-07 (plus charge control agent manufactured by Orient Chemical Co., Ltd.)
Add 2.9 parts and add Eiger Motor Mill M-25
0 allowed to mix for 1 hour. Hereinafter, this is referred to as a mixture (M-3).

Next, 20 parts of a 1N aqueous solution of sodium hydroxide was added to 100 parts of the mixture (M-3) [where the resin (A) became a self-water dispersible resin. ], Using a three-one motor, 350 rpm
While stirring, 200 parts of water was added to this at 20 ml / m.
The mixture was added dropwise at a rate of in to perform phase inversion emulsification.

Subsequently, the organic solvent was removed from the resulting aqueous medium dispersion by distillation under reduced pressure to obtain an aqueous dispersion (II-3). The average particle diameter of the self-water-dispersible resin particles containing the positive charge control agent in the aqueous dispersion obtained here was 55 nm as a result of measurement using a CHDF particle size distribution measurement system.

Aqueous dispersion (I-1) used in Example 1
And the amount by which the solid content of the aqueous dispersion (II-3) is 0.6% by weight (the amount of the charge control agent added to the toner is 0.2% by weight) based on the solid content (toner) of (I-1). Was uniformly mixed with aqueous dispersion (II-3), and adjusted with distilled water so that the total solid content was 20%. Under stirring, a 0.1N aqueous hydrochloric acid solution was dropped at a rate of 4 ml / min until the pH of the solution became 2, and the mixture became self-water dispersible by neutralization containing a positive charge control agent. The resulting resin was fixed on the toner surface.

Next, the liquid medium was filtered from the mixture, the wet cake was washed with water, and the wet cake was freeze-dried, so that the surface of the resin-treated surface having a volume average particle diameter of 8.4 μm was added with a positive charge control agent. Was obtained. The toner particles are converted to silica HDK H3050 (manufactured by Wacker Inc.) using a Henschel mixer.
Was externally added to prepare a toner (C).

Comparative Example 1 Carbon black [basic carbon black manufactured by Cabot Corporation of the United States of America] was used for 38 parts of the resin obtained in Reference Example 1 and having a nonvolatile content adjusted to 50%. .8 parts, 11.7 parts of Bontron S-34, "Eiger motor mill M-250"
[Eiger Japan Co., Ltd.] mixed for 1 hour. Hereinafter, this is referred to as a mixture (M-3).

Then, 1.8 parts of triethylamine and 12 parts of isopropyl alcohol were added to 100 parts of the mixture (M-3), and the mixture was stirred with water at 350 rpm using a three-one motor. Of 20
0 parts was added dropwise at a rate of 20 ml / min to perform phase inversion emulsification.

Subsequently, the organic solvent was removed from the resulting aqueous medium dispersion by distillation under reduced pressure to obtain an aqueous dispersion (III).

The aqueous dispersion (III) was adjusted with distilled water so that the total solid content was 20%. Under stirring, a 0.1N aqueous hydrochloric acid solution was added dropwise at a rate of 4 ml / min until the pH of the solution became 2.

Next, the liquid medium was filtered from the mixture, the wet cake was washed with water, and the wet cake was freeze-dried to obtain powder particles. The volume average particle diameter of the particles measured by Coulter Multisizer 2 was 8.3 μm. Toner (a-1) was prepared by externally adding 0.5% of silica R972 (manufactured by Nippon Aerosil Co., Ltd.) to the powder particles using a Henschel mixer.

Comparative Example 2 The aqueous dispersion (I-1) of the self-water-dispersible resin particles obtained in Example 1 was adjusted with distilled water so that the total solid content was 20%. Under stirring, a 0.1N aqueous hydrochloric acid solution was added dropwise at a rate of 4 ml / min until the pH of the solution became 2.

Next, the liquid medium was filtered from the dispersion, the wet cake was washed with water, and the wet cake was freeze-dried to obtain a powder having a volume average particle diameter of 8.3 μm.

Bontron S-34 was pulverized with a paint conditioner and pulverized to a weight average particle size of 200 nm. Bontron S-34 fine powder in an amount of 0.05% based on the weight of the obtained powder was externally added to the particle surface of the obtained powder using a Henschel mixer, and the volume average particle diameter was 8.6.
A powder of μm toner particles was obtained. Toner (a-2) was prepared by externally adding 0.5% of silica R972 (manufactured by Nippon Aerosil Co., Ltd.) to the toner particles using a Henschel mixer.

Comparative Example 3 A liquid medium was filtered from the aqueous dispersion liquid (I-2) obtained in Example 2, the wet cake was washed with water, and the wet cake was freeze-dried, whereby powder of resin particles was obtained. Obtained.

Bontron S-34 was pulverized with a paint conditioner and pulverized to a weight average particle size of 200 nm. 7. Bontron S-34 fine powder in an amount of 0.05% based on the weight of the obtained powder was externally added to the particle surface of the obtained powder using a Henschel mixer, and the volume average particle diameter was 8.
A powder of toner particles of 3 μm was obtained. Toner (b-1) was prepared by externally adding 0.5% of silica R972 (manufactured by Nippon Aerosil Co., Ltd.) to the toner particles using a Henschel mixer.

The obtained toner was observed with a scanning electron microscope, and it was confirmed that each of the toners was spherical. Evaluation tests were performed on the toner powders of Examples 1 to 3 and Comparative Examples 1 to 3 obtained as described above as follows.

<Measurement of Charge Amount> Toners (A), (B),
(C), (a-1), (a-2), and (b-1) were stirred by a ball mill in an environment of normal temperature and normal humidity (20 ° C., 50% RH), and the charge amount during the elapsed time Was measured respectively.

The negatively charged toners (A), (B), (a)
-1), (a-2), and (b-1) use a silicon resin-coated ferrite carrier (product of Powder Tech), and a positively charged toner (C) uses a fluoroacrylic resin-coated magnetite carrier, and has a toner concentration of 3 %, A two-component developer was prepared in addition to the toner of each example, and the charge amount was measured by a blow-off method. Table 2 shows the measurement results.

When the toners (A) and (B) of the example and the toners (a-2) and (b-1) of the comparative example were compared, the charge amounts at the initial stage of mixing were almost the same in both the example and the comparative example. However, in the comparative example toner, the charge amount was significantly reduced with the passage of time. Further, a toner (a-
1) showed only a low charge amount despite the addition amount of the charge control agent being higher than that of the toner (A). The toner (C) exhibited stable positive chargeability.

<Image Forming Test Using Non-Magnetic One-Component Printer> The toner (A) and the toner (a-2) were subjected to an image forming test on an IBM laser printer 4019 continuously for 1,000 sheets.

The toner (A) has a substantially constant image density.
The high image density of 1.5 to 1.6 is maintained, whereas the image density of the toner (a-2) is low at 1.1 to 1.3, and gradually decreases as the number of prints increases. A trend was seen. Further, the background fog did not occur at all with the toner (A), but was slightly observed from the beginning with the toner (a-2), and increased with the number of prints.

[0150]

[Table 2]

[0151]

According to the present invention, an aqueous dispersion of resin particles containing a colorant and an aqueous dispersion of particles of a self-water-dispersible resin and / or a water-soluble resin containing a charge controlling agent, which are separately prepared, are mixed. By depositing resin fine particles containing a charge control agent on the surface of the resin particles, and drying the obtained particles to obtain a toner having the charge control agent fixed on the surface, good charge characteristics can be obtained with a small amount of charge control agent. Can be expressed. This is particularly noticeable when an aqueous dispersion of particles comprising a self-water-dispersible resin and / or a water-soluble resin containing a charge control agent is used. Further, according to the present method, a positively charged toner or a negatively charged toner can be produced regardless of the polarity of the resin particles containing the colorant.

Claims (7)

[Claims] 1. A thermoplastic resin region (ii) in which a charge control agent (F) is uniformly dissolved or dispersed to submicron or less and has a functional group which increases hydrophilicity by neutralization, comprises a resin (A) and a colorant. And (B) are fixed to the surface of the particles (C), which are essential components, and are substantially spherical particles. 2. An aqueous dispersion (I) of particles (C) comprising a resin (A) and a colorant (B) as essential components and a self-water-dispersible resin and / or a water-soluble resin by neutralization. The self-dispersible resin (D2) and / or the water-soluble resin (H2) obtained by neutralizing the resulting resin (D1, H1) with the neutralizing agent (E) and the charge control agent (F) are essential components. Obtained by subjecting the mixture to phase inversion emulsification in an aqueous medium, wherein the charge control agent (F) is dissolved or dispersed and contained in a submicron or less, and has an average particle size smaller than that of the particles (C). , (D2) or (H2) particle aqueous dispersion (I)
I) and the neutralizing agent (E) and the neutralizing agent (K) having the opposite polarity to the neutralizing agent (E) are added, and then the liquid medium is removed and dried. A method for producing a fixed toner. 3. A self-water-dispersible resin (L2) obtained by neutralizing a resin (L1) whose particles (C) can become self-water-dispersible by neutralization with a neutralizing agent (N), and a colorant A colorant (B) obtained by subjecting a mixture containing (B) as an essential component and, if necessary, an organic solvent (M) dissolving (L2) to phase inversion in an aqueous medium is included. 3. The production method according to claim 2, wherein the particles are formed particles. 4. The method according to claim 2, wherein the self-water dispersible resin (D2) and the water-soluble resin (H2) have an anionic hydrophilic group. 5. The method according to claim 4, wherein the anionic hydrophilic group is a carboxyl group. 6. The method according to claim 2, wherein the charge controlling agent (F) is used in an amount of 0.001 to 5 parts by weight per 100 parts by weight of the solid content of the particles (C). 7. The method according to claim 2, wherein (D1), (H1) and (L1) are selected from the group consisting of polyester resins, polyurethane resins, epoxy resins and acrylic / styrene resins. The production method according to 5 or 6.