JPH0588408A - Manufacture of toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To provide a toner having an excellent offset resistant effect in heat roll fixing, excellent charge quantity stability against time elapse, and a long service life, and forming a high quality image by uniformly bonding mold releasing agent fine particles only to surfaces of coloring resin particles, and also fixing them securely. CONSTITUTION:In a process wherein a coloring resin particle is mixed with a mold releasing agent fine particle so as to coat the coloring resin particle with the mold releasing agent fine particle, the coloring resin dispersed in water, hydrophilic organic liquid or mixture thereof is mixed with the mold releasing agent fine particle dispersed in this liquid or liquid compatible with this liquid. At least a cationic surface active agent is included in the resultant mixed dispersion substance so as to uniformly bond the mold releasing agent fine particle to the coloring resin particle and thereafter the coloring resin particle is coated with the mold releasing agent fine particle by means of mechanical impact force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic recording,
The present invention relates to a method for producing a dry toner for developing an electrostatic charge image in electrostatic printing or the like.

[0002]

2. Description of the Related Art Generally, in an electrophotographic method or an electrostatic recording method, a developing sleeve is used for developing an electrostatic latent image formed on a latent image carrier made of a photoconductive photoconductor or a dielectric. For example, the toner image is thinned by a blade on a toner supply roller, developed with toner that is appropriately charged and made into a fine powder, and the toner image is transferred to a material to be copied such as paper, and then heated. It is fixed by pressure, solvent vapor or the like to obtain a copy.

As a method of fixing the toner image transferred from the latent image carrier onto the material to be copied, a pressure heating method using a heating roller is generally used. In this method, fixing is carried out by passing the toner image surface of the material to be fixed in pressure contact with the surface of a heating roller whose surface is formed of a material having releasability for toner, and is generally heated. Although it is called a roller fixing method, since the surface of the heating roller and the toner image surface of the material to be fixed are in pressure contact with each other in this method, the thermal efficiency when fusing the toner image on the material to be fixed is extremely good. Yes, it can be fixed quickly. However, in this method, a part of the toner image adheres to the surface of the fixing roller, and the toner on the roller surface adheres to the material to be fixed again to contaminate the copy image, which is a so-called offset phenomenon. .. Therefore, it is essential to prevent the transfer of toner to the rollers.

Therefore, in order to prevent offset, a method of supplying a releasable liquid such as silicon oil to the surface of the fixing roller to coat the roller surface with a thin film of the liquid, and a toner containing a releasable resin. Method (Japanese Patent Publication Sho 52-33)
No. 04) or a combination thereof. However, the method of applying release oil to the surface of the fixing roller has drawbacks such that the fixing device is equipped with an oil applying device, resulting in an increase in cost, and further, odor caused by the release oil is involved during fixing. Further, in the method of incorporating a release agent in the toner, when a general low molecular weight polypropylene is used as the release agent, the toner is offset to the fixing roller when the temperature becomes high. To do.

In the case of the kneading type toner, the compatibility between the binder resin and the releasing material is poor, so that phase separation occurs, and if the kneading is not sufficiently carried out, the sea-island structure in the phase separation causes the mold releasing. The size of the islands formed by the material becomes very large, which causes photoconductive photoconductor filming, developing sleeve filming, carrier spent, and the like, which is not preferable. Further, in order to solve the above-mentioned problems, a kneading time of 5 times or more is required as compared with the toner without the release material, which is a cost problem.

In order to solve such a problem, JP-A-56-144436 proposes a toner to which a release agent is externally added. However, in this toner, the release agent contaminates the triboelectrification imparting member such as a carrier during actual use, which causes a decrease in chargeability, and the release agent filmed on the photoconductor, resulting in poor image quality due to poor characteristics of the photoconductor. However, there is a problem in that Further, a release agent fine particle having a smaller particle size than the toner is attached to the surface of the toner whose main component is a binder resin, a dye / pigment or a charge control resin, or a toner having the fine particles further attached to the surface is used. Attempts have been made to fix it by mechanical impact. But,
In this method, if the release agent particles are not uniformly adhered to the toner surface as the primary particles, the toner characteristics such as the triboelectrification property of the toner vary, causing scumming and toner scattering, and high fidelity and high quality. I can't get a good image. Further, during actual use, the release agent fine particles are detached from the toner, the photoconductive photoconductor filming, the developing sleeve filming, or the triboelectric charging member is contaminated to lower the charging property, resulting in a decrease in the toner durability, etc. Causes a problem.

[0007]

As described above, when the release agent particles are externally added by a general method, the charging property of the toner is adversely affected, or the toner is offset to the fixing roller. Also, when the release agent fine particles are attached to the toner surface by mechanical impact force, etc., if the fine particles are not uniformly attached as primary particles on the toner surface, scumming and toner scattering However, there is a problem in that photoconductor filming, developing sleeve filming, and the like occur.

Therefore, an object of the present invention is to provide a manufacturing method capable of easily obtaining a toner which solves such a problem. More specifically, it is a toner that forms a high-quality image with excellent resolving power, line reproducibility, halftone dot reproducibility, and halftone reproducibility.
To provide a manufacturing method capable of preventing an offset phenomenon without using a releasing oil such as a silicone oil in heat roll fixing, and having a uniform initial charge, and easily obtaining a toner excellent in stability of charge amount over time. To do.

As a result of intensive studies, the inventors of the present invention have found that a manufacturing method including a specific release agent fine particle coating step meets the above object, and have completed the present invention.

That is, according to the present invention, in a method for producing a toner for developing an electrostatic image containing a resin, a colorant and a release agent as main components, the toner is dispersed in water or a hydrophilic organic liquid or a mixture thereof. The colored resin particles and the release agent particles dispersed in the liquid or a liquid compatible with the liquid are mixed, and the release agent particles are formed by adding at least a cationic surfactant to the mixed dispersion. Provided is a method for producing a toner for developing an electrostatic charge image, which comprises a step of uniformly attaching to a colored resin particle and then coating the release resin particle with the colored resin particle by a mechanical impact force.

As described above, generally, when fixing is performed using the heating roller fixing method, the toner on the material to be fixed contacts the fixing roller under pressure and heating, so that part of the toner image is formed on the surface of the fixing roller. There is a case where a so-called offset phenomenon occurs in which the toner adheres to the surface of the roller and re-attaches to the material to be fixed to contaminate the copied image. For that reason, it is necessary to prevent the transfer of the toner to the roller, and it is necessary to supply a liquid having a releasing property such as silicone oil, to make the toner contain a resin having a releasing property, or to make the toner have a releasing property. A method of mixing the resin fine particles contained therein, or adhering the release agent particles to the surface of the toner and applying mechanical energy to fix the toner is fixed.

On the other hand, the toner in which the release agent is fixed on the surface of the colored resin particles contaminates the developing sleeve, the carrier, or the photosensitive member with time, that is, so-called filming and the change in the toner charge amount with time. There is a phenomenon that occurs.
As a result of analysis, it was found that the main component of this filming substance is a low-molecular-weight releasing agent such as low-molecular-weight polypropylene, low-molecular-weight polyethylene, wax, etc., which has been fixed on the toner surface and has a releasing action.

Further, when the change of the toner surface with time is analyzed by a scanning electron microscope, the release agent is significantly desorbed when the release agent is unevenly immobilized on the toner surface. It was revealed that the homogeneity of the solidified state depends on the homogeneity of the adhered state of the release agent particles in the mixed particles formed during the immobilization treatment.

As a method for forming the mixed particles, a method has been used in which the colored resin particles and the release agent particles are in a dry powder state and the two are stirred and mixed. When the resin particles and the release agent particles are respectively dried, the particles easily aggregate, and even when the particles containing the aggregate thus obtained are mixed and stirred, the obtained mixed particles are separated on the colored resin particle surface. An agglomerate of a mold agent is attached, a release agent is attached to an agglomerate of colored resin particles, or a mixture of an agglomerate of colored resin particles and an agglomerate of a release agent, Since the mixture may be a mixture thereof, such a non-uniform mixed particle subjected to the immobilization treatment causes the above problem.

Therefore, as a result of earnest studies, the present inventors have found that when the release agent is fixed on the surface of the colored resin particles, in order to obtain a state in which the release agent is uniformly attached to the surface of the colored resin particles, The respective dispersion liquids of the resin particles and the release agent fine particles were mixed, and the release agent fine particles were adhered onto the colored resin particles in the liquid. However, at this time, the colored resin particles and the release agent particles adsorb some ions or substances having a polar group on the particle surface in the liquid in which they are dispersed, or the surface dissociation, and further the ions accompanying the surface dissociation. Or a polar group-containing substance is adsorbed to form a so-called electric double layer and is charged to any electric charge that can be generally measured as ζ potential. Therefore, the colored resin particle dispersion liquid and the release agent dispersion liquid are dispersed. When the liquid is mixed, the release agent fine particles and the colored resin particles are charged with the same polarity electric charge, and when they are stably dispersed, both particles electrostatically repel each other, resulting in separation to the surface of the colored resin particles. The mold agent particles cannot be evenly attached. When particles having such ζ potential of the same polarity are mixed, the resulting mixed particles form a mixture of agglomerates similar to the above.

Therefore, in the present invention, a cationic surfactant is mixed with either the releasing agent dispersion liquid and the colored resin particle dispersion liquid, which are charged to the same polarity in the liquid, or a mixture of both. , Changing the charge of the colored resin particles and the release agent particles in the liquid. This makes it possible to uniformly attach the release agent fine particles onto the colored resin particles.

The method for producing the toner for developing an electrostatic image of the present invention will be described in detail below. The colored resin particles used in the present invention are used in a form in which the colored resin particles are not dissolved in water or a hydrophilic organic liquid, or a mixed liquid of both, and the colored resin particles are prepared by, for example, a conventionally known method. Toner particles are used. The toner particles prepared by the conventionally known method here are
For example, it means a toner particle obtained by melting and kneading a binder resin, a colorant, and a charge control agent with a hot roll of 120 ° C., cooling and solidifying, crushing this with a jet mill, and classifying.

As the binder resin used in this case,
All those conventionally used as a binder resin for toner are applicable. Specifically, polystyrene, polychlorostyrene, homopolymers of styrene such as polyvinyltoluene, and substituted products thereof; styrene / p-chlorostyrene copolymers, styrene / propylene copolymers, styrene /
Vinyltoluene copolymer, styrene / vinylnaphthalene copolymer, styrene / methyl acrylate copolymer, styrene / ethyl acrylate copolymer, styrene / butyl acrylate copolymer, styrene / octyl acrylate copolymer, Styrene / methylmethacrylate copolymer, styrene / ethylmethacrylate copolymer, styrene / butylmethacrylate copolymer, styrene / α-chloromethylmethacrylate copolymer, styrene / acrylonitrile copolymer, styrene / vinylmethyl Ether copolymer, styrene / vinyl ethyl ether copolymer, styrene / vinyl methyl ketone copolymer, styrene / butadiene copolymer, styrene / isoprene copolymer, styrene / acrylonitrile / indene copolymer, styrene / maleic acid Copolymer, styrene Styrene copolymers such as maleic acid ester copolymers; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester,
Polyvinyl butyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenol resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, and the like. Used alone or in combination of two or more.

As the colorant, all known colorants for toner can be used. As a black colorant,
For example, carbon black, aniline black, furnace black, lamp black and the like can be used. Examples of cyan colorants include phthalocyanine blue, methyllen blue, Victoria blue, methyl violet,
Aniline blue, ultramarine blue, etc. can be used. Examples of magenta coloring agents include rhodamine 6G
Rake, dimethylquinacridone, watching red,
Rose bengal, rhodamine B, alizarin rake, etc. can be used. As the yellow colorant, for example, chrome yellow, benzidine yellow, Hansa yellow, naphthol yellow, molybdenum orange, quinoline yellow, tartrazine and the like can be used.

Further, these toners may contain, for example, dyes and pigments, charge control agents and the like in order to impart more efficient charging. Examples of the charge control agent include metal complex salts of monoazo dyes, nitrohumic acid and salts thereof,
Examples include metal complexes of salicylic acid, naphthoic acid, dicarboxylic acid such as Co, Cr, or Fe, organic dyes, and quaternary ammonium salts.

Such a dispersion liquid of toner particles can be obtained by mixing with water or an organic liquid which does not dissolve toner particles. At this time, as a dispersion stabilizer in the liquid,
A generally known anionic surfactant, nonionic surfactant, or a mixture of both may be contained. Specific examples thereof include the following.

(Anionic surfactant) Fatty acid salt, rosin salt, naphthene salt, ether carboxylate, alkenyl succinate, N-acyl sarcosine salt, N-acyl glutamate, primary alkyl sulfate, secondary sulfate Salts of carboxylic acids such as alkyl salts, alkyl polyoxyethylene sulfates, alkylphenyl polyoxyethylene sulfates, monoacyl glyceryl sulfates, acylamino sulfate esters, sulfuric acid oils, sulfated fatty acid alkyl esters; α-olefin sulfonates , Secondary alkane sulfonate, α
-Sulfo fatty acid, acyl isethionate, N-acyl-
N-methyl tauric acid, dialkyl sulfosuccinate,
Sulfonic acid salts such as alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkyl diphenyl ether disulfonates, petroleum sulfonates, lignin sulfonates; phosphoric acid esters such as alkyl phosphates and alkyl polyoxyethylene phosphates Salts; Sulfonic acid-modified and carboxyl-modified silicon-based anionic surfactants; Fluorine-based surfactants such as perfluoroalkylcarboxylic acid salts, perfluoroalkylsulfonic acid salts, perfluoroalkylphosphoric acid esters, and perfluoroalkyltrimethylammonium salts; Others Lipids, biosurfactants, oligo soaps, etc.

(Nonionic surfactant) alkyl polyoxyethylene ether, alkyl polyoxyethylene,
Polyoxypropylene ether, fatty acid polyoxyethylene ester, fatty acid polyoxyethylene sorbitan ester, fatty acid polyoxyethylene sorbitol ester, polyoxyethylene castor oil, polyoxyethylene adduct such as alkyl polyoxyethylene amine and amide; fatty acid sorbitan ester, fatty acid Polyhydric alcohols such as polyglycerin ester, fatty acid sucrose ester and alkylolamide; polyether modification, alkyl aralkyl polyether modification, epoxy polyether modification, alcohol modification, fluorine modification, amino modification, mercapto modification, epoxy modification, allyl Silicone-based surfactants such as denaturation; Fluorine-based surfactants such as perfluoroalkylethylene oxide adducts; Other lipid-based and biosurfers Tanto, an oligo such as soap.

The colored resin particles used in the present invention include:
Particles having a uniform particle diameter are more preferable, and for example, a colored resin particle dispersion liquid obtained by coloring particles obtained by an emulsion polymerization method using an anionic polymer dispersant is more preferably used. The colored resin particle-dispersed liquid having such a uniform particle size is obtained, for example, as follows.

In the preferable polymer particles, a polymer dispersant which is soluble in the organic liquid is added to the hydrophilic organic liquid, which is further dissolved in the organic liquid, but the polymer produced is in the organic liquid. It is produced by adding and polymerizing at least one vinyl monomer that swells or hardly dissolves (hereinafter, the resin particles thus obtained are referred to as resin particles A). Resin particles A thus obtained
Is usually a volume average particle diameter (Dv) and a number average particle diameter (Dp)
Is in the range of 1.00 ≦ (Dv / Dp) ≦ 1.20, and Dv is 1 to 10 μm. Generally Dv of resin particles
Is more than 10 μm, sufficient image quality cannot be achieved, and conversely, if it is less than 1 μm, the cleaning property becomes insufficient. When Dv / Dp exceeds 1.20, D
Depending on v, sufficient image quality may not be achieved.

The method for producing the resin particles A also includes a reaction in which a polymer having a particle size smaller than the intended particle size but a narrow particle size distribution is used in advance to grow in the above system. The monomer used for the growth reaction may be the same monomer used to produce the seed particles or a different monomer, but the polymer should not be dissolved in the hydrophilic organic liquid.

Examples of the hydrophilic organic liquid used as a diluent for the monomers used during the formation of seed particles and during the growth reaction of seed particles include methyl alcohol, ethyl alcohol, modified ethyl alcohol, isopropyl alcohol, n-butyl alcohol, and the like. Isobutyl alcohol, tert-butyl alcohol, sec-butyl alcohol, tert
Alcohols such as amyl alcohol, 3-pentanol, octyl alcohol, benzyl alcohol, cyclohexanol, furfuryl alcohol, tetrahydrofurfuryl alcohol, ethylene glycol, glycerin, diethylene glycol; methyl cellosolve, cellosolve, isopropyl cellosolve, butyl cellosolve, ethylene glycol Examples thereof include ether alcohols such as monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. These organic liquids can be used alone or as a mixture of two or more kinds.

[0028] Organic liquids other than alcohols and ether alcohols can be used in combination with the above-mentioned alcohols and ether alcohols under various conditions under which they are not soluble in the polymer particles of the organic liquid. By changing the SP value and changing the polymerization conditions, it is possible to suppress the size of particles produced, the coalescence of seed particles and the generation of new particles. In this case, as the organic liquid used in combination,
Hexane, octane, petroleum ether, cyclohexane,
Hydrocarbons such as benzene, toluene, xylene; halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene, tetrabromoethane; ethers such as ethyl ether, dimethyl glycol, trioxane, tetrahydrofuran; acetals such as methylal and diethyl acetal Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexane; Esters such as butyl formate, butyl acetate, ethyl probionate and cellosolve acetate; Acids such as formic acid, acetic acid and propionic acid;
Sulfur- and nitrogen-containing organic compounds such as nitropropene, nitrobenzene, dimethylamine, monoethanolamine, pyridine, dimethylsulfoxide and dimethylformamide; and water are also included.

SO ₄ ions (-2 valences), NO ₂ ions (-1 valences), PO
₄ ions (-3 valence), Cl ion (-1 valence), Na ion (+1 valence), K ion (+1 valence), Mg ion (+2)
Valence), Ca ions (+2 valences), and other inorganic ions may be present for polymerization. The average particle size, particle size distribution, drying conditions, etc. of the polymer particles to be produced can be adjusted by changing the type and composition of the mixed solvent at the start of polymerization, during the polymerization, and at the end of the polymerization.

Suitable examples of the polymeric dispersant used in the production of seed particles or the production of grown particles include, for example, acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, croton. Acids, fumaric acid, maleic acid, maleic anhydride, and other acids; hydroxyl group-containing acrylic monomers such as β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-methacrylic acid -Hydroxypropyl, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl acrylate, 3 methacrylic acid
-Chloro-2-hydroxypropyl, diethylene glycol monoacrylic acid ester, diethylene glycol monomethacrylic acid ester, glycerin monoacrylic acid ester, glycerin monomethacrylic acid ester, N-methylol acrylamide, N-methylol methacrylamide, etc .; with vinyl alcohol or vinyl alcohol Ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether and the like; esters of compounds containing vinyl alcohol and a carboxy group, such as vinyl acetate, vinyl propionate and vinyl butyrate; acrylamide, methacrylamide, diacetone Acrylamide or a methylol compound thereof; homopolyester such as acid chlorides such as acrylic acid chloride and methacrylic acid chloride -Or copolymer system; polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxypropylene alkylamine, polyoxyethylene alkylamide, polyoxypropylene alkylamide, polyoxyethylene nonylphenyl ether, polyoxyethylene laurylphenyl Examples thereof include polyoxyethylene-based resins such as ether, polyoxyethylene steacrylic phenyl ether, and polyoxyethylene nonylphenyl ether; and celluloses such as methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose.

Further, the above-mentioned hydrophilic monomer and styrene, α
-Methylstyrene, those having a benzene nucleus such as vinyltoluene, derivatives thereof or copolymers such as acrylonitrile, methacrylonitrile, acrylic acid or methacrylic acid derivatives such as acrylamide; further, crosslinkable monomers such as ethylene glycol dimethacrylate, Copolymers with diethylene glycol dimethacrylate, allyl methacrylate, divinylbenzene and the like can also be used.

These polymeric dispersants are appropriately selected depending on the hydrophilic organic liquid to be used, the seeds of the intended polymer particles and the production of seed particles or the production of grown particles. In order to prevent sterically mainly from one aspect, a polymer having a high affinity for the polymer particle surface and an adsorptive property and a high affinity for a hydrophilic organic liquid and a high solubility is selected. Further, in order to increase the repulsion between the particles in a three-dimensional manner, one having a molecular chain of a certain length, preferably one having a molecular weight of 10,000 or more is selected. However, if the molecular weight is too high, the liquid viscosity will remarkably increase, the operability and the stirring property will be deteriorated, and the precipitation probability of the produced polymer on the particle surface will vary, so caution is required. In addition, some of the monomers of the above-mentioned polymer dispersant,
It is also effective for stabilization to make the target polymer particles coexist with the monomer constituting the target polymer particles.

Further, together with these polymer dispersants, metals such as cobalt, iron, nickel, amylminium, copper, tin, lead and magnesium or alloys thereof (particularly preferably having a particle size of 1 μm or less); iron oxide, oxidation Fine powders of inorganic compounds of oxides such as copper, nickel oxide, zinc oxide, titanium oxide and silicon oxide; anionic surfactants such as higher alcohol sulfate ester salts, alkylbenzene sulfonates, α-olefin sulfonates and phosphate esters An amine salt type such as an alkylamine salt, an aminoalcohol fatty acid derivative, a polyamine fatty acid derivative, or imidazoline, an alkyltrimethylammonium salt, a dialkyldimethylammonium salt, an alkyldimethylbenzylammonium salt, a pyridinium salt, an alkylisoquinolinium salt, or benzethonium chloride. Fourth-class Ammo Nonionic surfactants such as fatty acid amide derivatives and polyhydric alcohol derivatives; amino acids such as alanine [eg, dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine] The combined use of an amphoteric surfactant of the type or betaine can further improve the stability and particle size distribution of the polymer particles produced.

Generally, the amount of the polymer dispersant used in the production of the seed particles varies depending on the kind of the polymerizable monomer for forming the intended polymer particles, but it is usually used with respect to the hydrophilic organic liquid.
It is 0.1 to 10% by weight, preferably 1 to 5% by weight.
When the concentration of the polymeric dispersant is low, the polymer particles produced have a relatively large particle size, and when the concentration is high, a small particle size is obtained, but 10% by weight is used. Even if it is used in excess, it has little effect on reducing the particle size.

The above-mentioned polymer dispersant and inorganic fine powders, pigments, and surfactants added as necessary are, of course, necessary in the production of seed particles, but in the growth reaction. In order to prevent the particles from coalescing with each other, the polymerization may be carried out by allowing the particles to be present in a vinyl monomer solution or seed particle dispersion liquid to be added.

The particles initially formed are stabilized by the polymer dispersant distributed in equilibrium between the hydrophilic organic liquid and the polymer particle surface. When present in considerable amount in the liquid, it has some swelled tackiness and overcomes the steric repulsion of the polymeric dispersants and agglomerates. Furthermore, when the amount of the monomer is extremely large with respect to the hydrophilic organic liquid, the produced polymer is completely dissolved and does not precipitate unless the polymerization proceeds to some extent. The state of precipitation in this case takes the form of forming a highly sticky lump. Therefore, the amount of the monomer with respect to the hydrophilic organic liquid at the time of producing the particles is naturally limited, and although the amount is slightly different depending on the kind of the hydrophilic organic liquid, the monomer / hydrophilic organic liquid ratio is approximately 1 or less,
It is preferably 1/2 or less.

The vinyl monomer here is one that is soluble in a hydrophilic organic liquid, such as styrene or o-.
Methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene, p-ethyl styrene, 2,
4-dimethylstyrene, pn-butylstyrene, p-
tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene, p-methoxy styrene, p-phenyl styrene, p
-Styrenes such as chlorostyrene and 3,4-dichlorostyrene; methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, acrylic acid Lauryl, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α-chloromethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate. , N-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-methacrylate
Α-Methyl fatty acid monocarboxylic acid esters such as ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, acrylamide; vinyl chloride , Vinylidene chloride,
50% by weight of vinyl halides such as vinyl bromide and vinyl fluoride, alone or in a mixture with each other.
It means a mutual mixture of the above-mentioned monomers which can be copolymerized with these.

The polymer may be polymerized in the presence of a so-called cross-linking agent having two or more polymerizable double bonds in order to enhance the offset resistance. As the cross-linking agent preferably used, divinylbenzene, divinylnaphthalene and aromatic divinyl compounds which are derivatives thereof, other ethylene glycol dimethacrylate, diethylene glycol methacrylate, triethylene glycol methacrylate, trimethylolpropane triacrylate, allyl methacrylate, tert-butyl. Adiethylenic carboxylic acid esters such as aminoethyl methacrylate, tetraethylene glycol methacrylate, 1,3-butanediol dimethacrylate, N, N
-All divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone and compounds having three or more vinyl groups are mentioned, and these are used alone or as a mixture.

When the growth polymerization reaction is subsequently carried out by using the seed particles thus crosslinked, the inside of the growing polymer particles becomes crosslinked. On the other hand, when the vinyl monomer solution used for the growth reaction contains the above-mentioned cross-linking agent, a polymer whose particle surface is hardened is obtained.

Further, for the purpose of controlling the average molecular weight, polymerization may be carried out in the presence of a compound having a large chain transfer constant. For example, a low molecular weight compound having a mercapto group, carbon tetrachloride, carbon tetrabromide, etc. may be mentioned.

Examples of the polymerization initiator for the monomer include azo polymerization initiators such as 2,2'-azobisisobutyronitrile and 2,2'-azobis (2,4-dimethylvaleronitrile), Peroxide type polymerization initiators such as lauryl peroxide, benzoyl peroxide, tert-butyl peroctoate, persulfide type initiators such as potassium persulfate or a system in which sodium thiosulfate, amine, etc. are used in combination Used. The concentration of the polymerization initiator is preferably 0.1 to 10 parts by weight with respect to 100 parts by weight of the vinyl monomer.

The polymerization conditions for obtaining the resin particles A are the concentrations and blending ratios of the polymer dispersant and the vinyl monomer in the hydrophilic organic liquid in accordance with the target average particle size of the polymer particles and the target particle size distribution. The ratio is determined. Generally, if the average particle size of the particles is to be reduced, the concentration of the polymer dispersant is set high, and if the average particle size is to be increased, the concentration of the polymer dispersant is set to be low. On the other hand, if the particle size distribution is to be made extremely sharp, the vinyl monomer concentration is set low, and if the particle size distribution is relatively wide, the vinyl monomer concentration is set high.

The resin particles A are manufactured by completely dissolving the polymer dispersant in the hydrophilic organic liquid, and then using one or more vinyl monomers, a polymerization initiator, and other inorganic fine powder, if necessary. Add surface active agents, dyes, pigments, etc.
With normal stirring at rpm, preferably at low speed,
Moreover, by using a turbine-type stirring blade rather than a paddle-type stirring blade and heating at a temperature corresponding to the decomposition rate of the initiator used while stirring while stirring at a rate that makes the flow in the tank uniform, polymerization is performed. Done. Since the temperature at the initial stage of polymerization has a great influence on the particle size to be generated, it is desirable to raise the temperature to the polymerization temperature after adding the monomer, and to dissolve the initiator in a small amount of solvent and add it. At the time of polymerization, it is necessary to sufficiently expel oxygen in the air in the reaction vessel with an inert gas such as nitrogen gas or argon gas. If the oxygen purge is insufficient, fine particles are likely to be generated.

To carry out the polymerization in a high polymerization rate range, 5 to 40
Polymerization time is required, but the polymerization rate can be increased by stopping the polymerization in the state of the desired particle size and particle size distribution, by sequentially adding the polymerization initiator, and by conducting the reaction under high pressure. be able to. After the completion of the polymerization, it may be used as it is in the dyeing step, or after removing unnecessary fine particles, residual monomer, polymer dispersant and the like by operations such as sedimentation separation, centrifugation and decantation, the polymer slurry May be collected and dyed. However, if the polymer dispersant is not removed, the stability of the dyeing system is high and unnecessary aggregation is suppressed.

(Dye Dyeing Step) In the present invention, the resin particles A obtained as described above are subsequently dyed, and the dyeing is performed as follows. That is, the resin particles A are dispersed in an organic solvent that does not dissolve the resin particles A, and before and after this, the relationship between the solubility of the dye in the solvent [D ₁ ] and the solubility of the dye in the resin of the resin particles [D ₂ ] is [ A dye satisfying D ₁ ] / [D ₂ ] ≦ 0.5 is dissolved in the solvent, and the dye is permeated into the resin particles to be colored;
After that, the solvent is removed. By this method, colored resin particles (hereinafter referred to as colored particles B) in which the dye penetrates (diffuses) to the deep part of the resin particles A can be efficiently produced. Becomes

In the present invention, the solubility is 25 ° C.
Is defined as measured at a temperature of. The solubility of the dye in the resin has exactly the same definition as the solubility of the dye in the solvent, and means the maximum amount of the dye that can be contained in the resin in a compatible state. The observation of the dissolved state or the deposited state of the dye can be easily performed by using a microscope. In addition, in order to know the solubility of the dye in the resin, an indirect observation method may be used instead of the above direct observation method. In this method, a liquid having a solubility coefficient similar to that of a resin, that is, a solvent that dissolves the resin well is used, and the solubility of the dye in the solvent is determined as the solubility in the resin.

The dye used for dyeing has a ratio [D ₁ ] of the solubility [D ₁ ] of the dye in the organic solvent used and the solubility [D ₂ ] of the dye in the resin constituting the resin particles A. ] /
[D ₂ ] needs to be 0.5 or less. In particular,
[D ₁ ] / [D ₂ ] is preferably 0.2 or less.

The dye is not particularly limited as long as it satisfies the above-mentioned solubility characteristics. However, a water-soluble dye such as a cationic dye or an anionic dye may have a large environmental change, and the resistance of the toner may become low, resulting in a transfer. Use of vat dyes, disperse dyes, and oil-soluble dyes is preferable, and oil-soluble dyes are particularly preferable, because the rate may deteriorate. Further, several kinds of dyes can be used together depending on the desired color tone. The ratio (weight) of the dye to be dyed and the resin particles A is arbitrarily selected according to the degree of coloring, but usually 1 to 50 parts by weight of the dye is preferable with respect to 100 parts by weight of the resin particles.

For example, resin particles A are prepared by using alcohols such as methanol and ethanol having a high SP value as the dyeing solvent.
When a styrene / acrylic resin having an SP value of about 9 is used as the dye, examples of dyes that can be used include the following dyes. CI SOLVENT YELLOW (6,9,17,31,35,100,102,103,105) CI SOLVENT Orange (2,7,13,14,66) CI SOLVENT RED (5,16,17,18,19,22,23,143,145,146,1
49,150,151,157,158) CI SOLVENT VIOLET (31,32,33,37) CI SOLVENT BLUE (22,63,78,83 ~ 86,91,94,95,104) CI SOLDENT GREEN (24,25) CI SOLDENT Brown (3,9) etc.

Commercially available dyes include, for example, Hodogaya Chemical Co., Ltd. vertical dye SOT dyes Yellow-1,3,4, Orange-1,2,3, Scarlet-1,
Red-1,2,3, Brown-2, Blue-1,2, Violet-1, Green-1,2,
3, Black-1,4,6,8 and BASF sudan dye, Yellow-140,15
0, Orange-220, Red-290,380,460, Blue-670 and Mitsubishi Kasei's dialresin, Yellow-3G, F, H2G, HG, HC, HL, Orange
-HS, G, Red-GG, S, HS, A, K, H5B, Violet-D, Blue-J, G, N,
K, P, H3G, 4G, Green-C, Brown-A and oil color of Orient Chemical Co., Yellow-3G, GG-S, # 105, Orange-PS, PR, # 20
1, Scarlet- # 308, Red-5B, Brown-GR, # 416, Green-BG, #
502, Blue-BOS, IIN, Black-HBB, # 803, EE, EX, Sumiplast from Sumitomo Chemical Co., Blue GP, OR, Red FB, 3B, Yellow FL7G, GC, Nippon Kayaku Kayaron, Polyester Black EX-SF300, Kayaset Red-B blue A-2R, etc. can be used. Of course, since the dye is appropriately selected depending on the combination of the resin particles A and the solvent used at the time of dyeing,
It is not limited to the above example.

As the organic solvent used for dyeing the resin particles A with the dye, those which do not dissolve the resin particles A used or those which cause some swelling, specifically, the solubility parameter of the organic solvent [SP Value] and the [SP value] of the resin particles used are 1.0 or more, preferably 2.
Zero or more are used. For example, for a styrene / acrylic resin, an alcohol type such as methanol, ethanol or n-propanol having a high [SP value] or n-hexane or n-heptane having a low [SP value] is used. Of course, if the difference in [SP value] is too large, the wetting of the resin particles A is deteriorated, and good dispersion of the resin particles cannot be obtained. Therefore, the difference in [SP value] is preferably 2 to 5.

As a method of dyeing, it is preferable to disperse the resin particles A in an organic solvent in which the dye is dissolved, and then maintain and stir the liquid temperature below the glass transition temperature of the resin particles A. As a result, the permeation rate of the dye into the resin particles A can be increased, and the resin particles B that are sufficiently colored can be obtained in about 30 minutes to 1 hour. The stirring method may be carried out using a commercially available stirrer such as a homomixer or a magnetic stirrer.

Further, the dye is directly added to the slurry obtained at the end of the polymerization by dispersion polymerization, that is, the solution in which the polymerized resin particles A are dispersed in the organic solvent, and the mixture is heated and stirred under the above conditions. Good. If the heating temperature exceeds the glass transition temperature, fusion of the resin particles will occur.

The method of drying the slurry after dyeing is not particularly limited, but it may be air-dried after filtering, or vacuum drying after filtering, or direct vacuum drying without filtering. In the present invention, the colored particles B obtained by air-drying or reduced-pressure drying after filtering are almost free from aggregation.
Reproduce with little damage to the particle size distribution of the injected resin particles.

(Step of coating release agent fine particles) In the present invention, subsequently, toner particles prepared by a conventionally known method,
Preferably, the surface of the colored resin particles such as the colored particles B obtained as described above is coated with the release agent fine particles.
This coating process is performed as follows. That is, the colored resin particles and the release agent fine particles are wet-mixed in the presence of a cationic surfactant to uniformly attach the release agent fine particles to the surface of the colored resin particles, and then mechanically. The release agent particles are fixed to the colored resin particles by energy, and the release agent particles are firmly fixed (coated) on the surface of the colored resin particles by this treatment. A durable toner is obtained, and a toner having excellent offset resistance in heat roll fixing is obtained.

The release agent used in the present invention may be any substance as long as it has an effect of preventing the adhesion of the toner on the heat roller and the material to be fixed when fixing the heat roller, for example, a low molecular weight polyolefin. There are kinds and waxes and others. In this case, the following may be mentioned as specific examples of the waxes.

Carnauba wax, cotton wax, candelilla wax, sugar cane wax, beeswax, spermaceti wax, shellac wax, wool wax, etc. in a narrow sense; mineral wax such as montan wax, paraffin wax, microcrystalline wax, or petroleum wax; palmitic acid, stearic acid, Solid higher fatty acids having 6 to 22 carbon atoms such as hydroxystearic acid and behenic acid; oleic acid amide, stearic acid amide, palmitic acid amide, N-hydroxyethyl-hydroxystearoamide, N, N'-ethylene-bis-stearoamide , N, N'-ethylene-bis-ricinolamide, N, N'-ethylene-bis-hydroxystearylamide and the like having 6 to 22 carbon atoms (hereinafter, the term "higher" has 6 to 22 carbon atoms as described above). Shall be used in the sense) fatty acid amides; For example, alkali metal salts of higher fatty acids such as calcium stearate, aluminum stearate, magnesium stearate, calcium palmitate, alkaline earth metal salts, zinc salts, aluminum salts, and the like; higher salts such as palmitic acid hydrazide, stearic acid hydrazide. Hydrazides of fatty acids; p-hydroxyanilides of higher fatty acids such as p-hydroxyanilide of myristic acid, p-hydroxyanilide of stearic acid; β-diethylaminoethyl ester hydrochloride of lauric acid, β-diethylaminoethyl ester hydrochloride of stearic acid Β-diethylaminoethyl ester hydrochloride of higher fatty acid such as; stearic acid amide-formaldehyde condensate, higher fatty acid amide such as palmitic acid amide-formaldehyde condensate-formaldehyde Condensates; Petroleum-based residues such as asphalt and gilsonite; Rubbers such as nitrile rubber and chlorinated rubber; Synthetic hydrocarbons such as Fischer-Tropsch wax and derivatives; Fatty acid esters and glycerides such as polyethylene glycol and sorbitol stearate; Chlorinated paraffins , Halogenated hydrocarbons such as chlorinated propylene; hydrogenated castor oil, hydrogenated tallow oil, etc.

In using the release agent, the release agent is water or a hydrophilic organic liquid which does not dissolve the colored resin particles and the release agent, and is compatible with the liquid used to disperse the colored resin particles. It is preferable that the liquid is stably dispersed in the form of fine particles.

As a method for obtaining such a release agent-dispersed liquid, there are the following methods, for example, and they can be obtained as commercial products. (1) The solution a in which the release agent is dissolved and the solution a are compatible with each other,
A method of using a solution b in which the release agent is not dissolved, dissolving the release agent in a, and then adding to the solution b stirred at a high speed to cause precipitation. (2) A method of obtaining a dispersion liquid of a release agent by adding hot water to a liquid obtained by heat-melting a release agent while stirring at high speed, and cooling the obtained dispersion liquid. (3) A method in which a liquid c which does not dissolve the release agent and a release agent are mixed and dispersed in the liquid using a dispersing device such as a ball mill dispersion mixer.

Further, these dispersions may contain an anionic surfactant or a nonionic surfactant or a mixture of both as a dispersion stabilizer. Specific examples of these surfactants in this case include the same surfactants as those exemplified for the dispersion liquid of the toner particles.

The volume average particle diameter r of the release agent fine particles in the release agent dispersion liquid thus obtained is preferably 5 or more with respect to the volume average R of the colored resin particles used. .. If R / r is less than 5, it becomes impossible to uniformly adhere and fix the colored resin particles, and the uniformity of charging and the durability of the toner are lost.

Next, the step of uniformly adhering the release agent particles to the surface of the colored resin particles will be described in detail.
In order to obtain the mixed particles by mixing the respective dispersion liquids of the colored resin particles and the release agent particles as described above, there are the following methods. (1) A method in which a cationic surfactant is added to a colored resin particle dispersion liquid and the mixture is stirred and mixed, and then the dispersion liquid is stirred and mixed with a release agent fine particle dispersion liquid. (2) A method in which a cationic surfactant is added to the release agent fine particle dispersion liquid and the mixture is stirred and mixed, and then the dispersion liquid is stirred and mixed with the colored resin particle dispersion liquid. (3) A method in which a release agent fine particle dispersion liquid and a colored resin particle dispersion liquid are stirred and mixed, and then a cationic surfactant is added to the dispersion liquid and stirred and mixed. (4) In the case where a cationic surfactant is used as a dispersion stabilizer in the release agent dispersion liquid when the dispersion liquid is prepared,
A method of stirring and mixing a release agent fine particle dispersion liquid and a colored resin particle dispersion liquid.

As the cationic surfactant used here, known ones may be used alone or in combination of two or more. Specific examples thereof include the following.

Primary amine salts, acylaminoethyldiethylamine salts, N-alkyl polyalkylene polyamine salts, fatty acid polyethylene polyamides, amides and salts thereof, alkyl amines such as amine salts, salts of acyl amines; alkyl trimethyl ammonium salts, Dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, alkylpyridinium salt, acylaminoethylmethyldiethylammonium salt, acylaminopropyldimethylbenzylammonium salt, acylaminopropyldiethylhydroxyethylammonium salt, acylaminoethylpyridinium salt, diacylamino Quaternary ammonium salts such as ethylammonium salts or ammonium salts having an amide bond; diacyloxyethylmethylhydroxye Luminum salts, esters such as alkyloxymethylpyridinium salts, ammonium salts having an ether bond; imidazolines such as alkyl imidazolines, 1-hydroxyethyl-2-alkyl imidazolines, 1-acylaminoethyl-2-alkyl imidazolium salts, Imidazolium salts; amine derivatives such as alkyl polyoxyethylene amines, N-alkylaminopropyl amines, N-alkyl polyethylene polyamines, N-acyl polyethylene polyamines and fatty acid triethanol amine esters; other lipid systems, biosurfactants, oligo soaps and the like.

Further, these cationic surfactants can be used as a mixture with a nonionic surfactant.
Specific examples of the nonionic surfactant include the same surfactants as those exemplified for the dispersion liquid of toner particles.

When the release agent particles are adhered to the surface of the colored resin particles in this manner, the coverage of the release agent particles on the surface of the colored resin particles is preferably 90% or less. The coverage here is calculated from the volume average particle diameter of the colored resin particles and the release agent fine particles, when the release agent fine particles are further coated on the colored resin particles,
When the maximum number of release agent particles that can be filled on the surface of one colored resin particle is Mmax and the number of release agent particles actually attached to one colored resin particle is Mn, (Mn / M
It is a value calculated as (max) × 100%. When the coverage is 90% or more, the toner characteristics are dominated by the release agent on the surface, so that the obtained toner is inferior in the charge stability, fluidity and durability.

Further, in the present invention, the release agent fine particles are firmly attached to the colored resin particles to prevent the fine particles from coming off, and further improve the durability and reliability of the obtained toner. In order to firmly attach the fine particles, in the present invention, the release agent fine particles are driven and fixed to the colored resin particles by mechanical energy.

As a method for implanting the release agent fine particles, mechanical energy is applied to the mixed particles of the colored resin particles and the release agent fine particles. As a method of giving mechanical energy, a method of applying an impact force to the mixture by a blade rotating at a high speed, a method of introducing the mixture into a high-speed air stream to accelerate particles,
There is a method of colliding particles with each other or particles with an appropriate collision plate. Specific equipment used here is an Ong mill (Hosokawa Micron Co., Ltd.), a type I mill (Nippon Pneumatic Mfg. Co., Ltd.), which has a lower pulverizing air pressure than in the case of normal pulverization, and a hybridization system (Nara Machinery). Factory), automatic mortar, etc.

Further, in the present invention, since the release agent fine particles are adhered to the colored resin particles in the liquid, the fixing treatment may be carried out by the above-mentioned apparatus after drying, but it is fixed in the drying step. Processing can also be performed. For example, drying and immobilization can be performed at the same time using a medium fluidized drying device MSD (Nara Machinery Co., Ltd.), a fluidized bed drying device slurry dryer (Okawara Seisakusho), and the like.

The toner obtained in the present invention may be mixed with additives as required. Examples of the additives include hydrophobic silica as a fluidity improving agent, metal oxides such as alumina, polyvinylidene fluoride as a lubricant, and fine powder of zinc stearate.

[0071]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. The parts and% shown below are based on weight.

(Preparation of Dispersion Stabilizer Solution for Resin Particles) The following was charged into a sealable reaction container which rotates in a constant temperature water bath. Methanol 100 parts Dispersion stabilizer 7 parts The container was gently stirred at room temperature to completely dissolve polyvinylpyrrolidone in about 1 hour. At this time, as the dispersion stabilizer, a methyl vinyl ether / partial methyl ester copolymer of maleic anhydride (copolymerization ratio 1/1: average weight molecular weight 40,000) was used.

(Preparation of Resin Particle Dispersion) 250 parts of a methanol solution in which a dispersion stabilizer was dissolved was transferred into a rotatable reaction container in a constant temperature water tank, and the following materials were charged. Styrene 60 parts Methyl methacrylate 40 parts Dodecyl mercaptan 1.0 part 1,3-Butanediol dimethacrylate 1.5 parts While mixing by rotating the container, blow nitrogen gas into the container to completely expel air. ,
The container was closed. Then keep the water bath at 60 ℃ and
Polymerization was carried out with stirring at 0 revolutions. At this time, 2.0 parts of 2,2′-azobisisobutyrotolyl was used as an initiator to initiate polymerization. The polymerization was further continued and completed in 24 hours.

20 μm by Coulter Multisizer
When measuring the particle size distribution with a Percher tube, the number of particles is 5
Volume average particle diameter of 5 μm and number average particle diameter of 6 at 10,000 counts.
The thickness was 600 μm and the ratio was 1.02. This polymer dispersion was designated as Resin Particle Dispersion No. 1, the dispersed resin particles are designated as resin particle No. Set to 1.

(Preparation of Colored Resin Particles) Oil Black 8
20 parts of methanol was added to 30.0 parts of 60, dissolved by heating, cooled, and filtered to obtain 10 parts of a filtrate with a 1 μm microfilter. In 100 parts of the filtrate thus prepared, the resin particle No. 40 parts of 1 was added, and the mixture was stirred at 50 ° C. for 2 hours, then the dispersion was cooled to room temperature, centrifuged to remove the supernatant, and redispersed in a mixed solvent of 50 parts of methanol and 50 parts of water three times. Go, oil black 860
Resin particles No. A dispersion of 1 was obtained. Colored resin particle dispersion No. Set to 1.

(Preparation of Release Agent Dispersion Liquid) Preparation Example 1 Carnauba wax 2 in a container that can be sealed in an oil bath.
After adding 0 part and gradually heating and melting at 100 ° C, the nonionic surfactant polyoxyethylene nonylphenyl ether (average oxyethylene addition mole number =
15) Add 5 parts and dissolve completely. Thereafter, 75 parts of 98 ° C. water is gradually added with high speed stirring with a homomixer, and after further stirring for 10 minutes, the mixture is allowed to cool to 25 ° C. with stirring. After that, the stirring was stopped, and after standing for 6 hours, the precipitate was removed and the release agent dispersion liquid No. Got 1.

The obtained release agent dispersion liquid No. 1 was measured with a dynamic light scattering meter DLS700 (manufactured by Otsuka Electronics Co., Ltd.),
Volume average particle size is 0.371 μm, number average particle size is 0.3
It was 12 μm and the ratio was 0.841.

Preparation Example 2 In the preparation of the release agent dispersion liquid, the release agent dispersion liquid No. 1 was prepared in the same manner as in Preparation Example 1 except that the addition amount of the nonionic surfactant to be dissolved was 10 parts. 2 was prepared, and the particle size was measured by DLS700 in the same manner. The particles obtained have a volume average particle diameter of 0.110 μm and a number average particle diameter of 0.04.
9 μm, the ratio was 0.445.

The release agent dispersion liquid No. In 2,
Since the generation of aggregates was remarkable and the particle size distribution was poor, by further centrifuging the coarse aggregates and filtering the supernatant, the volume average particle size was 0.037 μm and the number average particle size was 0.030 μm. Release agent dispersion No. 1 having a ratio of 0.81. Got 2.

(Production of Mixed Particle Dispersion of Release Agent and Colored Resin Particles) Preparation of Cationic Surfactant Solution Stearylamine acetate, which is a cationic surfactant, is dissolved in water to prepare stearyl with a concentration of 0.1%. Amine acetate aqueous solution A was prepared.

Production Example 1 Release Agent Dispersion Liquid No. 1 was diluted with water to have a solid content of 5% and sufficiently stirred to obtain a release agent dispersion liquid B. Also,
In another container, the colored resin particle dispersion No. 1 for solids 1
Dilute to 0% with water, and stir the mixture at a constant temperature of 25 ° C. under stirring with rotation to add the above stearylamine acetate aqueous solution A to 0.001 part of stearylamine acetate based on the solid content of the colored resin particles. Mix so that 2
After rotating and stirring for 1 hour at a constant temperature of 5 ° C., the release agent dispersion B was mixed with 0.0755 parts of the release agent solid content per 1 part of the colored resin particle solid content while stirring at 25 ° C. constant temperature. Was gradually added to obtain a dispersion liquid of mixed particles in which fine particles of the release agent adhered to the colored resin particles. The mixed particle dispersion liquid was mixed particle dispersion liquid No. Set to 1. The mixed particles thus obtained had a particle size ratio R / r = 16 of the colored resin particles and the release agent particles and a coverage rate of 30%.

Production Example 2 In Production Example 1, the release agent dispersion B was prepared such that the release agent solid content was 0.179 parts with respect to the colored resin particle solid content of 1 part.
Except that in the same manner as in Production Example 1,
Mixed particle dispersion liquid No. 1 in which release agent particles adhere to colored resin particles Got 2. The mixed particles thus obtained are
The particle size ratio of the colored resin particles to the release agent particles was R / r = 16, and the coverage was 70%.

Production Example 3 In Production Example 1, the release agent dispersion No. The release agent dispersion liquid B prepared by using 2 was added so that the release agent solid content was 0.00665 parts with respect to 1 part of the colored resin particle solid content. Except for manufacturing example 1
Similarly to the above, mixed particle dispersion liquid No. 1 in which release agent fine particles are adhered to colored resin particles. Got 3. The mixed particles thus obtained have a particle size ratio R of the resin-colored particles and the release agent particles.
/ R = 166, coverage = 30%.

Production Example 4 A mixed dispersion of colored resin particles and release agent fine particles was produced in the same manner as in Production Example 1 except that the same part of water was used instead of the stearylamine acetate aqueous solution A in Production Example 1. Got This is mixed dispersion No. Set to 4. The mixed particles thus obtained had a particle size ratio R / r of colored resin particles and release fine particles of 16 and a coverage of 30%.

Production Example 5 Release Agent Dispersion Liquid No. The release agent fine particle powder A was obtained by freeze-drying 1. Further, the colored particle dispersion liquid No. 1
Suction filtration and vacuum drying for one day were performed to obtain colored particle powder (a). To 1 part of the colored particles (a), 0.0755 part of the release agent fine powder A was added and mixed with a mixer for 30 seconds to prepare mixed powder No. Got 5. Observation of this powder with an optical microscope revealed that the powder contained 1 to 6 times the particle diameter of the colored particles.
A large number of release agent agglomerates about twice as large were confirmed.

Example 1 Mixed particle dispersion liquid No. 1 produced in Production Example 1 1 is subjected to solid-liquid separation by centrifugation, and water is further added for washing.
This was repeated twice, followed by suction filtration, followed by vacuum drying to take out the mixed particles. Further, 100 parts of the mixed particles were retained by a hybridizer NHS-1 type (manufactured by Nara Machinery Co., Ltd.) at a rotation speed of 7500 for 2 minutes for immobilization treatment, and then the obtained particles were obtained. 1.5 parts of hydrophobic silica was added as a fluidity-imparting agent, and mixed for 30 seconds with a mixer to obtain a toner of the present invention.

97 parts of a silicon resin-coated ferrite carrier having a particle size of 70 μm and 3 parts of the above toner were mixed and stirred in a ball mill for 20 minutes to prepare a developer. This developer was set in a copying machine (IMAGIO420 manufactured by Ricoh Co., Ltd. with the oil application device removed), and image evaluation, fixing test, durability test (100,000 sheets), and the like were performed.
The results are shown in Table 1. For the change with time of the charge amount, the toner charge amount was evaluated every 5000 sheets during the durability test.

Example 2 In Example 1, the mixed particle dispersion liquid No. 1 produced in Production Example 2 was used. A toner of the present invention was prepared in the same manner as in Example 1 except that 2 was used. Using the toner thus obtained, a developer was prepared in the same manner as in Example 1, and the developer thus obtained was used and evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 3 In Example 1, the mixed particle dispersion liquid No. 1 produced in Production Example 3 was used. A toner of the present invention was prepared in the same manner as in Example 1 except that No. 3 was used. Using the toner thus obtained, a developer was prepared in the same manner as in Example 1, and the developer thus obtained was used and evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 In Example 1, the mixed particle dispersion liquid No. 1 produced in Production Example 4 was used. A comparative toner was prepared in the same manner as in Example 1 except that No. 4 was used. At this time, the mixed dispersion liquid N
o. When 4 was centrifuged, the release agent particles did not adhere to the colored resin particles, so that they were separated.

Using the toner thus obtained, a developer was prepared in the same manner as in Example 1, and the developer thus obtained was used.
Evaluation was carried out in the same manner as in Example 1. The results are shown in Table 1. This toner was inferior in reliability due to the occurrence of offset and paper jam from the start of the durability test.

Comparative Example 2 Mixed powder No. 1 in Example 1 was used. A comparative toner was prepared in the same manner as in Example 1 except that No. 5 was used.

Using the toner thus obtained, a developer was prepared in the same manner as in Example 1, and the developer thus obtained was evaluated in the same manner as in Example 1. The results are shown in Table 1. This toner is a toner that causes offset and paper jam from the start of the durability test, and a large number of released release agents were confirmed in the developer. Furthermore, in the durability test, 2
The toner was inferior in reliability in which filming of the release agent was confirmed on the photoreceptor after the 000th sheet.

Comparative Example 3 A comparative toner was prepared in the same manner as in Example 1 except that the immobilization treatment by the hybridizer was not performed.

Using the toner thus obtained, a developer was prepared in the same manner as in Example 1, and the developer thus obtained was used and evaluated in the same manner as in Example 1. The results are shown in Table 1. This toner was inferior in reliability in which image unevenness was observed on the 500th sheet in the durability test and filming of the release agent was confirmed on the photoconductor.

[0096]

[Table 1]

[0097]

According to the method for producing a toner for developing an electrostatic image of the present invention, water or a hydrophilic organic liquid is used in the step of mixing colored resin particles and release agent particles and coating the release agent particles with the colored resin particles. Alternatively, the colored resin particles dispersed in a mixture thereof and the release agent fine particles dispersed in the liquid or a liquid compatible with the liquid are mixed, and at least a cationic surfactant is added to the mixed dispersion. Since the release agent fine particles are uniformly adhered to the colored resin particles by being contained, the release agent fine particles are coated on the colored resin particles by a mechanical impact force. Since the release agent fine particles can be uniformly adhered and firmly fixed, the method of the present invention has an excellent anti-offset effect in the heat roll fixing, and the charge amount with the passage of time. It is possible to obtain a toner to form a high quality image with excellent long life stability.

Front page continuation (72) Inventor Ian Harpa 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (3)

[Claims] 1. A method for producing a toner for developing an electrostatic charge image, which comprises a resin, a colorant and a release agent as main components, and colored resin particles dispersed in water or a hydrophilic organic liquid or a mixture thereof, The release agent fine particles are uniformly mixed with the colored resin particles by mixing the liquid or the release agent fine particles dispersed in a liquid compatible with the liquid, and containing at least a cationic surfactant in the mixed dispersion. A method for producing a toner for developing an electrostatic charge image, comprising a step of coating fine particles of a release agent with colored resin particles by a mechanical impact force after adhesion. 2. The electrostatic charge image developing toner according to claim 1, wherein a ratio R / r of the volume average particle diameter R of the colored resin particles and the volume average particle diameter r of the release agent fine particles is 5 or more. Production method. 3. The method for producing an electrostatic charge image developing toner according to claim 1, wherein the coating rate of the release agent fine particles on the colored resin particles is 90% or less.