JPH07325432A - Toner for electrostatic image development - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide an electrostatic image developing toner which stably imparts appropriate chargeability to toner particles for a long period of time and provides a good copy image permanently. [Composition] In a mixed pulverized toner, a dispersion polymerization toner or a suspension polymerization toner for developing an electrostatic charge image, which contains a colorant, a binder resin and a charge control agent as a main component, at least a floroid or a mixture thereof is used as a charge control agent. To do.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic charge image formed in an electrophotographic method, an electrostatic recording method, an electrostatic printing method or the like.

[0002]

2. Description of the Related Art Generally, in an electrophotographic system or an electrostatic recording system, a toner such as a developing sleeve is used to develop an electrostatic charge image formed on a latent image carrier such as a photoconductive photoconductor or a dielectric. Using a toner that has been thinned by a blade or the like on the supply roller, and has been appropriately charged and made into a fine powder, and after development, a toner image is transferred to a transfer material such as paper, if necessary, and then heated under pressure. A copy is obtained by solvent vapor or the like (US Pat. No. 2,297,691, Japanese Patent Publication No. 42-23910, Japanese Patent Publication No. 43-24).
748).

The developing methods applied to these electrophotographic methods and the like are roughly classified into a dry developing method and a wet developing method. The former is further divided into a method using a two-component developer and a method using a one-component developer. A method using a two-component developer includes a magnet brush method using an iron powder carrier described in US Pat. No. 2874063, USP26, depending on the type of carrier that carries the toner.
There are a cascade method using a bead carrier described in 18552 specification, a fur brush method using a fur described in USP 2221776, and the like.

The method using a one-component developer includes a powder cloud method in which toner particles described in US Pat. No. 2,221,776 are used in a powder mist state, and toner particles are directly applied to an electrostatic latent image surface. Contact development method (contact development method or toner development) of contacting and developing, toner particles described in JP-B-41-9475 and USP2839400 are not brought into direct contact with the electrostatic latent image surface to charge the toner particles. And jumping developing method in which the electric field of the electrostatic latent image is caused to fly toward the latent image surface, USP3
The magnetic dry toner described in the specification of No. 909258 is brought into contact with the electrostatic latent image surface to develop the toner, and the like, such as a magnet dry method.

As the toner applied to these various developing methods, fine powder in which a colorant such as carbon black is dispersed in a binder resin made of natural resin or synthetic resin is used. For example, particles in which a colorant is dispersed in a binder resin such as polystyrene and finely pulverized to about 1 to 30 μm are used as the toner. Further, a magnetic toner such as those containing a magnetic material such as magnetite is used as a magnetic toner.

As described above, the toner used in various developing methods has a positive or negative charge depending on the polarity of the electrostatic image to be developed. To retain the electric charge in the toner, the triboelectric charging property of the resin, which is a component of the toner, can be used, but in this method, the toner charging property is small, and therefore the image obtained by the development is fogged and In many cases, charge deterioration occurs and a satisfactory image cannot be obtained. Therefore, generally, in order to impart a desired triboelectric charging property to the toner, JP-B-41-20153, JP-B-43-17955, and JP-B-43-27.
596, Japanese Patent Publication No. 6397, Japanese Patent Publication No. 45-2
As described in Japanese Patent No. 6478 and the like, addition of a dye, a pigment, or a charge control agent that imparts a charging property has been performed.

Examples of the negative charge control agent include metal complex salts of monoazo dyes, nitrohumic acid and its salts, metal complexes of salicylic acid, naphthoic acid, dicarboxylic acids such as Co, Cr and Fe, sulfonated copper phthalocyanine pigments, nitro groups or There are halogen-introduced styrene oligomers, chlorinated paraffins, melamine resins, and the like, but these dyes have a complicated structure, the properties are not constant, and the stability is poor. Further, during thermal kneading, decomposition or mechanical shock, friction, changes in temperature and humidity conditions, and the like easily cause decomposition or deterioration, and a phenomenon in which charge controllability is deteriorated is likely to occur. Also, in many cases, the chargeability changes depending on the environment. Furthermore, when a conventional toner containing the charge control agent is used for a long time, filming may occur on the photoconductor due to poor charging.

Furthermore, the dye / pigment or charge control agent added to these toners must be exposed to some extent on the toner surface in order to impart chargeability. Therefore, due to friction between the toner particles, collision with the carrier, friction with the electrostatic latent image holding member, etc., these additives fall off from the toner surface, resulting in contamination of the carrier or the like, or electrostatic latent image holding member such as a photoconductor. Contamination of belts or drums occurs. As a result, the charging property deteriorates, and the deterioration progresses as the number of durable sheets increases, the image density decreases, and fine line reproducibility and fog properties become practical problems. Therefore, it has been attempted to improve the above problems by improving the affinity and dispersibility of the binder resin of the toner and the dye / pigment or other charge control agent that imparts the charging property. For example, there is a method of treating the surface of these additives in order to increase the affinity, but the surface treatment often lowers the charging property.
Further, in order to improve the dispersibility, there is also a method of improving the mechanical shearing force to finely disperse it. However, in this case, the proportion of the additive appearing on the toner surface is decreased, and the chargeability tends not to be sufficiently imparted. Occurs.

As can be seen from the above description, the additives (dyes and pigments or other charge control agents) capable of stably imparting sufficient chargeability to the toner for a long period of time are very limited, and practically used. There are few. Further, in order to obtain not only a black and white image but also a color image, it is preferable that the one added to the toner is colorless, but most of the conventionally used dyes and pigments or other charge control agents are colored, Therefore, under the present circumstances, almost no one is put into practical use.

By the way, when the resin particles are prepared by the dispersion polymerization method described in JP-A No. 61-19602, a polymer dispersant is generally used. Therefore, the polymer dispersant remains on the surface of the resin particles, and when the dispersion-polymerized particles are made into toner, the charging property is controlled by the polymer dispersant remaining on the surface. When the surface on which the polymer dispersant remains is negatively charged, negative charge is obtained, but it is not sufficiently satisfied. Therefore, even if a negatively chargeable compound is attached to the negatively chargeable surface to give the negatively chargeable property, strong ionic repulsion cannot be given because the ionic repulsion is large. On the other hand, a positively chargeable ammonium salt, for example, has a good adhesion to the negatively chargeable surface, but has a weak chargeability, and it is substantially impossible to control the charge. The suspension polymerization toner and the kneaded and pulverized toner also have the same problems as the dispersion polymerization toner described above.

[0011]

As can be seen from the above, the additives (ie, dyes and pigments or charge control agents) that can stably impart sufficient chargeability to the toner for a long period of time are very limited. And, there are few that have been put to practical use. Further, in order to obtain not only a monochrome image but also a color image, it is preferable that the toner added is colorless.
Many of the conventionally used dyes and pigments or charge control agents have a dark color, and in that case, there are few that have been put into practical use. Therefore, the object of the present invention is to solve the above-mentioned problems, that is, to provide toner particles with stable and appropriate chargeability for a long period of time,
An object of the present invention is to provide a toner for developing an electrostatic charge image, which gives a good copy image permanently.

[0012]

As a charge control agent in a mixed pulverized toner for electrostatic image development, a dispersion polymerization toner or a suspension polymerization toner, which comprises a colorant, a binder resin and a charge control agent of the present invention as main components. At least a fulleroid or a mixture thereof is used. Here, the fulleroids are extended fullerenes in which CH ₂ is added to a spherical compound composed of only carbon atoms such as C ₆₀ . Regarding this Freroid, see J. Am. Chem. Soc. ，
115, 5829 (1993) and Helv. Chi
m. Acta, 76, 1231 (1993) describes synthesis and structure determination.

Normally, in the ground state, HOMO (High
st Occupied Molecular Orb
It has two orbits each having a lower orbital energy than that of the LUMO (Lowest Unocc).
There are no electrons in the orbits with a higher orbital energy than the uped molecular orbital).
When the compound is negatively charged, that is, when it receives an electron, the LUMO having the lowest energy among the orbits in which the electron does not exist becomes important. In a molecule with high symmetry such as Freloid, many molecular orbitals are degenerate, and LUMO is also degenerate into triple. Therefore, it has a higher ability to accept electrons than a chain or planar compound having low symmetry, and is easily negatively charged. In addition, since the toner is charged by repeatedly contacting and rubbing with a carrier or a blade which is a charging partner, the electronic state in the excited state of each component of the toner and the charging partner becomes important for each charging. . In the excited state, SOMO (Si
single Occupied Molecular O
rbital) played an important role in the transfer of electrons.

The orbital energy values of Freroid's LUMO and SOMO are determined by the inventor's earlier application (Japanese Patent Application No. 5-329).
No. 71, No. 6-26173), it is possible to negatively charge the toner more than when fullerene is used. Therefore, the contrast is good and the image quality is improved. The fulleroid is contained in the toner in an amount of 0.01 to 20% by weight, preferably 0.1 to 5% by weight. The synthesis of fulleroids is described in J. Am. Chem. Soc. , 115, 58
29 (1993) and Helv. Chim. Acta,
76, 1231 (1993).

(Dispersion Polymerized Toner) First, the explanation will be given from the “dispersion polymerized toner” of the present invention. [Resin Particle A] The resin particle A in the present invention is as follows. That is, the resin particles A have a volume average particle diameter (D
v) and the number average particle size (Dp) are 1.00 ≦ (Dv
/Dp)≦1.20 and Dv is 1 to 10 μm
Particles. The resin particles A are added to a hydrophilic organic liquid with a polymer dispersant that is soluble in the hydrophilic organic liquid, and the polymer particles are dissolved in the hydrophilic liquid, but the resulting polymer swells in the hydrophilic liquid. Or produced by adding and polymerizing one or more vinyl monomers which are almost insoluble. It also includes a reaction in which polymer particles having a particle size smaller than the target particle size and having a narrow particle size distribution are used to grow in the above system. The monomer utilized in the growth reaction may be the same monomer that produced the seed particles or a different monomer, but the polymer must not be soluble in the hydrophilic organic liquid.

[Hydrophilic Organic Liquid] The hydrophilic organic liquid as a diluent for the monomer used during the formation of the seed particles and the reaction for growing the seed particles is methyl alcohol, ethyl alcohol, denatured ethyl alcohol, isopropyl. Alcohol, n-butyl alcohol, isobutyl alcohol, t-butyl alcohol, s-butyl alcohol, t
Alcohols such as amyl alcohol, 3-pentanol, octyl alcohol, benzyl alcohol, cyclohexanol, furfuryl alcohol, tetrahydrofurfuryl alcohol, ethylene glycol, glycerin, and diethylene glycol, methyl cellosolve, cellosolve, isopropyl cellosolve, butyl cellosolve, ethylene glycol Representative examples 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. The organic liquid other than alcohols and ether alcohols is used in combination with the above-mentioned alcohols and ether alcohols, under the condition that the organic liquid does not have solubility in the produced polymer particles. It is possible to suppress the size of particles to be generated, the coalescence of seed particles and the generation of new particles by performing the polymerization while changing the SP value of. In this case, the organic liquid used in combination includes hydrocarbons such as hexane, octane, petroleum ether, cyclohexane, benzene, toluene and xylene, halogenated hydrocarbons such as carbon tetrachloride, trichloroethylene and tetrabromoethane, and ethyl ether. , Ethers such as dimethyl glycol, dioxane, and tetrahydrofuran, acetals such as methylal and diethyl acetal, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexane, butyl formate,
Butyl acetate, ethyl propionate, esters such as cellosolve acetate, acids such as formic acid, acetic acid, propionic acid, etc., nitropropene, nitrobenzene, dimethylamine, monoethanolamine, pyridine, dimethyl sulfoxide, dimethylformamide, etc. Compounds and other water are also included.

In the solvent containing the hydrophilic organic liquid as a main component,
The polymerization may be carried out in the presence of the following ions.

[Chemical 1] The average particle size, particle size distribution, drying conditions, etc. of the polymer particles 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.

[Dispersion Stabilizer] Suitable examples of the polymer 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. Acids, itaconic acid, crotonic acid, fumaric acid, acids such as maleic acid or maleic anhydride, or a hydroxyl group-containing acrylic monomer,
For example, β-hydroxyethyl acrylate, β-hydroxyethyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2 acrylate. -Hydroxypropyl, 3-chloro-2-hydroxypropyl methacrylate, 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., vinyl alcohol or ethers with vinyl alcohol, such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, etc., or esters of vinyl alcohol and compounds containing carboxyl groups, such as vinyl acetate, vinyl propionate. , Vinyl butyrate, acrylamide, methacrylamide, diacetone acrylamide or their methylol compounds, acid chlorides such as acrylic acid chloride and methacrylic acid chloride, nitrogen atoms such as vinylpyridine, vinylpyrrolidone, vinylimidazole and ethyleneimine or their heterocycles. Homopolymers or copolymers such as those having, polyoxyethylene, polyoxypropylene, polyoxyethylene alkylamine, polyoxyproline Polyoxyethylene-based such as renalkylamine, polyoxyethylenealkylamide, polyoxypropylenealkylamide, polyoxyethylenenonylphenylether, polyoxyethylenelaurylphenylether, polyoxyethylenestearylphenylester, polyoxyethylenenonylphenylester, And celluloses such as methyl cellulose, hydroxyethyl cellulose and hydroxypropyl cellulose, or the hydrophilic monomer and styrene, α-
Methylstyrene, those having a benzene nucleus such as vinyltoluene or a derivative thereof, or acrylonitrile, methacrylonitrile, a copolymer with an acrylic acid or methacrylic acid derivative such as acrylamide, and further a crosslinkable monomer such as ethylene glycol dimethacrylate,
Copolymers with diethylene glycol dimethacrylate, allyl methacrylate, divinylbenzene and the like can also be used.

These polymer dispersants are appropriately selected depending on the hydrophilic organic liquid to be used, the seed of the intended polymer particles, and the production of seed particles or grown particles. In order to prevent the unification of the polymer mainly in three dimensions, 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. Also,
In order to increase the repulsion between the particles in a three-dimensional manner, a molecular chain having a certain length, preferably a molecular weight of 10,000 or more is selected. However, when the molecular weight is too high, the viscosity of the liquid is remarkably increased, the operability and the stirring property are deteriorated, and the precipitation probability of the produced polymer on the surface of the particles is varied, so that 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 in the monomer constituting the particles.

Further, together with these polymer dispersants, metals such as cobalt, iron, nickel, aluminum, copper, tin, lead and magnesium or alloys thereof (particularly preferably having a particle size of 1 μm or less), iron oxide, copper oxide, Fine powder of inorganic compounds of oxides of nickel oxide, zinc oxide, titanium oxide, silicon oxide, etc., higher alcohol sulfuric acid ester salts, alkylbenzene sulfonates, α-olefin sulfonates, anionic surfactants such as phosphoric acid esters, alkyl Amine salts, amino alcohol fatty acid derivatives, polyamine fatty acid derivatives, amine salt types such as imidazoline, and alkyl trimethyl ammonium salts, dialkyl dimethyl ammonium salts, alkyl dimethyl benzyl ammonium salts, pyridinium salts, alkyl isoquinolinium salts, benzethonium chloride, etc. Fourth grade Nonionic surfactants such as ammonium salt type cationic surfactants, fatty acid amide derivatives and polyhydric alcohol derivatives, for example, amino acids such as alanine type “for example dodecyldi (aminoethyl) glycine, di (octylaminoethyl) glycine” The combined use of the amphoteric surfactants of the type and betaine can further improve the stability and particle size distribution of the polymer particles produced.

Generally, the amount of the polymeric 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 is 0.1% by weight based on the hydrophilic organic liquid. 10 to 10% by weight, preferably 1 to 5% by weight. When the concentration of the polymer dispersion stabilizer is low, the produced polymer particles have a relatively large particle size, and when the concentration is high, a small particle size is obtained. Even if used over the range, there is little effect on reducing the diameter.

[Monomer] Further, the above-mentioned vinyl monomer is one that can be dissolved in a hydrophilic organic liquid.
Styrene, o-methylstyrene, m-methylstyrene,
p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, pn-
Nonylstyrene, pn-decylstyrene, pn-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, and other styrenes, methyl acrylate, acrylic acid Ethyl, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, lauryl acrylate, acrylic acid 2
-Ethylhexyl, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-methacrylate. Α such as octyl, dodecyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate
-Methyl fatty acid monocarboxylic acid esters, acrylonitrile, methacrylonitrile, acrylic acid such as acrylamide, or methacrylic acid derivatives, vinyl chloride,
Meaning of vinylidene chloride, vinyl bromide, vinyl halide, and other vinyl halides, alone or as a mixture with each other, and with a monomer containing 50% by weight or more of these and copolymerizable with them. To do.

The above-mentioned polymer in the present invention 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 crosslinking agent preferably used,
Aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene and their derivatives, other ethylene glycol dimethacrylate, diethylene glycol methacrylate, triethylene glycol methacrylate, trimethylolpropane triacrylate, allyl methacrylate, tert-butylaminoethyl methacrylate, tetraethylene glycol dimeth Methacrylate, 1,
Examples include diethylenic carboxylic acid esters such as 3-butanediol dimethacrylate, all divinyl compounds such as N, N-divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone, and compounds having three or more vinyl groups. Are used alone or as a mixture.

When the growth polymerization reaction is subsequently carried out using the thus crosslinked seed particles, the inside of the growing polymer particles is 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 can be obtained.

[Chain Transfer Agent] Further, for the purpose of adjusting the average molecular weight, a compound having a large chain transfer constant in the presence of polymerization may be used, for example, a low molecular weight compound having a mercapto group, carbon tetrachloride, or tetrachloride. Carbon bromide may be mentioned.

[Polymerization Initiator] As the polymerization initiator of the above-mentioned monomer, for example, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), etc. Azo polymerization initiators, lauryl peroxide, benzoyl peroxide, t-butyl peroctoate and other peroxide polymerization initiators, potassium persulfate and other persulfate polymerization initiators, or sodium thiosulfate , A system in which an amine or the like is used in combination is 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.

[Polymerization Conditions] The polymerization conditions for obtaining the seed particles are: a polymer dispersant in a hydrophilic organic liquid; The concentration and blending ratio are determined. Generally, if the average particle size of the particles is reduced, the concentration of the polymer dispersant is set high, and if the average particle size is increased, the concentration of the polymer dispersant is set 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 distribution is relatively wide, the vinyl monomer concentration is set high.

The particles are produced by completely dissolving the polymer dispersion stabilizer in the hydrophilic organic liquid, and then using one or more vinyl monomers, a polymerization initiator, and other inorganic fine powder if necessary.
30-300r by adding surfactant, dye, pigment
With normal stirring of pm, it is preferable to use a stirring blade of a turbine type rather than a paddle type at a speed as low as possible while stirring at a speed such that the flow in the tank becomes uniform, It is carried out by heating at a temperature corresponding to the polymerization rate and polymerizing. Since the temperature at the initial stage of polymerization has a great influence on the type of particles produced, it is desirable to raise the temperature to the polymerization temperature after adding the monomer, and dissolve the polymerization initiator in a small amount of solvent before charging. 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. In order to carry out the polymerization in a high polymerization rate region, a polymerization time of 5 to 40 hours is required, but the polymerization may be stopped in the state of a desired particle size and particle size distribution, or a polymerization initiator may be added sequentially. The polymerization rate can be increased by carrying out the reaction under high pressure.

After completion of the polymerization, it may be used in the dyeing step as it is, or after removing unnecessary fine particles, residual monomer, polymer dispersion stabilizer and the like by operations such as sedimentation, centrifugation and decantation, You may collect | recover as a polymer slurry and dye. However, when the dispersion stabilizer is not removed, the stability of dyeing is higher and unnecessary aggregation is suppressed.

[Dyeing Step] Dyeing in the present invention is performed as follows. . That is, the resin particles A are dispersed in an organic solvent that does not dissolve the resin particles A, a dye is dissolved in the solvent before or after this, and the dye is permeated into the resin particles A for coloring, and then the organic solvent is added. In the method for producing a dyed toner by removing the dye, the relationship between the liquid solubility of the dye in the organic solvent (D ₁ ) and the solubility of the dye in the resin of the resin particles A (D ₂ ) is (D ₁ ) / (D
₂ ) Select and use a dye satisfying ≦ 0.5. This allows
It is possible to efficiently manufacture the toner in which the dye penetrates (diffuses) to the deep part of the resin particle A.

The solubility in this specification 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 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. This method may use a liquid having a solubility coefficient similar to that of the resin, that is, a solvent that dissolves the resin well, and the solubility of the dye in this solvent may be determined as the solubility in the resin.

[Dye] As the dye used for coloring, the solubility of the dye in the organic solvent used (D ₁ ) and the solubility of the dye in the resin constituting the resin particles (D ₂ ) are as described above. It is necessary that the ratio (D ₁ ) / (D ₂ ) of 0.5 be 0.5 or less. Further, (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, but a water-soluble dye such as a cationic dye or an anionic dye may have a large environmental change, and the electric resistance of the toner becomes low, which lowers the transfer rate. Therefore, it is preferable to use vat dyes, disperse dyes and oil-soluble dyes, and oil-soluble dyes are particularly preferable. 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 is arbitrarily selected according to the degree of coloring, but it is usually used in a ratio of 1 to 50 parts by weight of dye with respect to 100 parts by weight of resin particles. Is preferred.

For example, when an alcohol having a high SP value such as methanol or ethanol is used as the dyeing solvent and a styrene-acrylic resin having an SP value of about 9 is used as the resin particles, the dye that can be used is For example, the following dyes may be mentioned. CI SOLVENT YELLOW (6,9,17,31,35,1,102,103,105) 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 SOLVENT GREEN (24,25) CI SOLVENT BROWN (3,9) Such.

Among commercially available dyes, for example, Aizen SOT dyes Yellow-1,3,4 and Orange manufactured by Hodogaya Chemical Co., Ltd.
e-1, 2, 3, Scarlet-1, Red-1,
2,3, Brown-2, Blue-1,2, Viol
et-1, Green-1, 2, 3, Black-1,
4,6,8 and BASF Sudan dye, Yell
ow-140, 150, Orange-220, Red
-290, 380, 460, Blue-670 and Mitsubishi Kasei's dialresin, Yellow-3G, F, H2
G, HG, HC, HL, Orange-HS, G, Re
d-GG, S, HS, A, K, H5B, Violet-
D, Blue-J, G, N, K, P, H3G, 4G, G
reen-C, Brown-A and oil colors manufactured by Orient Chemical Co., Yellow-3G, GG-S, # 10.
5, Orange-PS, PR, # 201, Scarl
et- # 308, Red-5B, Brown-GR, #
416, Green-BG, # 502, Blue-BO
S, HN, Black-HBB, # 803, EE, E
X, Sumiplast made by Sumitomo Chemical Co., Ltd., Blue GP, O
R, red FB, 3B, yellow FL7G, GC, Nippon Kayaku's Kayaron, polyester black EX-SH
3. Blue A-2R of Kayaset Red-B or the like can be used. Of course, the dye is not limited to the above examples because it is appropriately selected depending on the combination of the resin particles and the solvent used for dyeing.

[Organic solvent for dyeing] The organic solvent used for dyeing the resin particles with the dye is one in which the resin particles to be used are insoluble or causes some swelling, specifically, a solubility parameter ( The difference in SP value) is 1.0 or more, preferably 2.0 or more. For example, for styrene-acrylic resin particles, alcohols such as methanol, ethanol and n-propanol having a high SP value, or n- having a low SP value.
Hexane, n-heptane, etc. are used. If the difference in SP value is too large, the wetting of the resin particles becomes poor, and good dispersion of the resin particles cannot be obtained.
The difference in P value is preferably 2-5.

[Dyeing Step] After the resin particles are dispersed in the organic solvent in which the dye is dissolved, it is preferable to keep the liquid temperature below the glass transition temperature of the resin particles and stir. This makes it possible to dye the resin particles while preventing them from aggregating. The stirring method may be carried out using a commercially available stirrer such as a homomixer or a magnetic stirrer. Further, the dye may be directly added to the slurry obtained at the end of the polymerization by dispersion polymerization, that is, the dispersion liquid in which the polymerized resin particles are dispersed in the organic solvent, and the mixture may be heated and stirred under the above conditions. If the heating temperature exceeds the glass transition temperature, fusion of the resin particles will occur. The method for drying the slurry after dyeing is not particularly limited, but it may be dried under reduced pressure after filtration or directly under reduced pressure without filtering. In the present invention, the colored particles obtained by air-drying or reduced-pressure drying after being filtered out have almost no aggregation,
Reproduce with almost no loss of the particle size distribution of the resin particles.

(Suspension Polymerization Toner) Next, the “suspension polymerization toner” of the present invention will be described. [Monomer] The polymerizable monomer used for suspension polymerization is a monomer having a vinyl group, and specific examples thereof include the following monomers. That is, styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene,
Examples thereof include styrene such as 2,4-dimethylstyrene, butylstyrene, and octylstyrene, and derivatives thereof, and among them, a styrene monomer is most preferable. Other vinyl monomers include ethylenically unsaturated monoolefins such as propylene, butylene, isobutylene, vinyl chloride, vinylidene chloride, vinyl bromide, vinyl halides such as vinyl fluoride, vinyl acetate, vinyl propionate. Vinyl esters such as vinyl benzoate and vinyl butyrate, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, -n-octyl acrylate, dodecyl acrylate, acrylic acid-2 -Ethylhexyl, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, α
-Methyl chloroacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isopropyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, methacrylic acid 2
-Α-methylene aliphatic monocarboxylic acid esters such as ethylhexyl, stearyl methacrylate, phenyl methacrylate, diethylaminoethyl methacrylate, acrylonitrile, methacrylonitrile, acrylic acid or methacrylic acid derivatives such as acrylamide, vinyl methyl ether, vinyl isobutyl ether Such as vinyl ethers, vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone and other vinyl ketones, N-vinyl pyrrole, N-vinyl carbazole, N
-N- such as vinylindole and N-vinylpyrrolidone
Examples thereof include vinyl compounds and vinylnaphthalene, and these monomers can be used alone or in combination.

[Crosslinking Agent] In order to form a crosslinked polymer in the monomer composition, suspension polymerization may be carried out in the presence of the following crosslinking agent. As the cross-linking agent, divinylbenzene, divinylnaphthalene, polyethylene glycol diacrylate, diethylene glycol diacrylate,
Triethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,6-hexane glycol dimethacrylate, neopentyl glycol diacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,
2'-bis (4-methacryloxydiethoxyphenyl) propane, 2,2'-bis (4-acryloxydiethoxyphenyl) propane, trimethylolpropane trimethacrylate, trimethylolmethane tetraacrylate, dibromoneopentyl glycol di Examples thereof include methacrylate and diallyl phthalate.

When the amount of the cross-linking agent used is too large, the toner is less likely to be melted by heat, resulting in poor heat fixing property and heat pressure fixing property. If the amount of the cross-linking agent used is too small, properties such as blocking resistance and durability required as a toner are deteriorated, and in the heat roll fixing, a part of the toner is not completely adhered to the paper and is adhered to the roll surface. Cold offset occurs in which the toner adheres and is transferred to the next paper. Therefore, the amount of the crosslinking agent used is 0.001 to 15 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the polymerizable monomer.
Parts by weight.

[Release Agent] In order to prevent offset of the obtained toner, the polymerization composition may contain a release agent. As a release agent, low molecular weight polyethylene,
Polyolefins such as polypropylene are preferred. This low molecular weight olefin polymer is preferably dispersed in a polymerizable monomer together with a colorant. The releasing agent is preferably used in an amount of 1 to 15 parts by weight based on 100 parts by weight of the polymerizable monomer. When the amount of the release agent used is less than 1 part by weight, the obtained toner does not have a sufficient release effect and is easily offset on the roller. On the other hand, if the amount used exceeds 15 parts by weight, the release agent will be spent from the toner on the frictional charge imparting member, and the fluidity of the toner will be extremely deteriorated.

[Colorant] As the colorant contained in the monomer, there are conventionally known dyes and pigments such as carbon black and grafted carbon black obtained by coating the surface of carbon black with a resin. It can be used. Other colorants include lamp black, iron black,
Ultramarine blue, nigrosine dye, aniline blue, phthalocyanine green, Hansa yellow G, rhodamine 6G, lake, chalco oil blue, chrome yellow, quinacridone, benzidine yellow, rose bengal, triallylmethane dye, monoazo dye, disazo dye, etc. There are dyes and pigments. In addition, these coloring agents can be used in an amount of 0.1 to 30 parts by weight based on 100 parts by weight of the polymerizable monomer.

[Dispersion Stabilizer] The following dispersion stabilizers can be used. That is, polyvinyl alcohol, starch, methyl cellulose, carboxymethyl cellulose, hydroxymethyl cellulose, sodium polyacrylate, water-soluble polymer such as sodium polymethacrylate, barium sulfate, calcium sulfate, barium carbonate, magnesium carbonate, calcium phosphate, talc, clay , Diatomaceous earth, metal oxide powder, etc. are used. These are preferably used in the range of 0.1 to 10% by weight with respect to water.

[Polymerization Initiator] In the present invention, the polymerization initiator may be added to the dispersion liquid containing the monomer composition after granulation, but is uniformly polymerized into individual monomer composition particles. From the viewpoint of adding an initiator, it is desirable to include the initiator in the monomer composition before granulation. As such a polymerization initiator,
2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1,
Azo- or diazo-type polymerization initiators such as 1'-azobis- (cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile and azobisbutyronitrile, benzoyl Examples thereof include peroxide type polymerization initiators such as peroxide, methyl ethyl ketone peroxide, isopropyl peroxide, 2,4-dichlorolylbenzoyl peroxide and lauryl peroxide.

[Magnetic Material] The toner of the present invention may be a magnetic toner containing a magnetic material. To obtain a magnetic toner, magnetic particles may be added to the monomer composition. Examples of magnetic materials that can be used in the present invention include powders of ferromagnetic metals such as iron, cobalt and nickel, and powders of alloys and compounds such as magnetite, hematite and ferrite. The magnetic particles have a particle size of 0.0
5 to 5 μm, preferably 0.1 to 1 μm is used, but when a small particle size toner is produced, the particle size is 0.8
It is desirable to use magnetic particles of μm or less. The magnetic particles are preferably contained in 10 to 60 parts by weight in 100 parts by weight of the monomer composition. Further, these magnetic particles may be treated with a surface treating agent such as a silane coupling agent or a titanium coupling agent, or an appropriate reactive resin. In this case, depending on the surface area of the magnetic particles or the density of hydroxyl groups present on the surface, the surface treatment agent is usually used in an amount of 5 parts by weight or less, preferably 0.1 to 3 parts by weight, based on 100 parts by weight of the magnetic particles. Thus, sufficient dispersibility in the polymerizable monomer is obtained, and the physical properties of the toner are not adversely affected.

[0046]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Example 1 In a 500 ml four-necked flask equipped with a stirring blade and a condenser, 3.5 parts by weight of methyl vinyl ether-maleic anhydride copolymer (molecular weight 40,000, manufactured by GAF) and 100 parts by weight of methanol were placed. Parts and stirred at 60 ° C. for 2 hours to completely dissolve the methyl vinyl ether-maleic anhydride copolymer to prepare a dispersion stabilizer. Then, the mixture was cooled to room temperature and charged with the following. Styrene 60 parts by weight Methyl methacrylate 40 parts by weight t-dodecyl mercaptan 0.06 parts by weight 1,3-butanediol dimethacrylate 0.5 parts by weight While stirring these, the inside of the flask was purged with nitrogen gas, The stirring was continued gently (100 rpm) for about 1 hour until the residual oxygen concentration became 0.1%. Then, after raising the temperature of the constant temperature water bath to 60 ° C., 0.2 parts by weight of 2,2′-azobisisobutyronitoyl was used as an initiator,
Polymerization was continued for 24 hours. After 15 minutes of heating, the liquid began to turn cloudy and remained a cloudy and stable dispersion after 24 hours of polymerization.

As a result of partially sampling and measuring by gas chromatography by the internal standard method, it was confirmed that the polymerization rate was 95%. When the obtained dispersion was cooled and centrifuged at 2000 rpm with a centrifuge, the polymer particles were completely settled and the upper liquid was transparent. The supernatant was removed, 200 g of methanol was newly added, and the mixture was washed with stirring for 1 hour. The procedure of centrifugation and washing with methanol was repeatedly filtered. The material separated by filtration was dried under reduced pressure at 50 ° C. for 24 hours to obtain resin particles of white powder with a yield of 90%. The obtained particles have a volume average particle diameter Dv = 5.4.
It was 4 μm. Also, Tg (glass transition point) is 63 ° C.
Met. Hereinafter, the polymer particles are referred to as (B).

Next, 2 parts by weight of Oil Black 860 (manufactured by Orient Chemical Co., Ltd.) was dissolved in 100 parts by weight of methanol by heating, cooled, and filtered with a filter of about 1 μm to prepare a dye solution. Then, the polymer particles (B) are added to the filtrate in an amount of 30
Parts by weight were added and dispersed, and the mixture was heated with stirring at 50 ° C. for 1 hour.
Then, the dispersion liquid was cooled to room temperature and filtered to obtain a colored resin fine particle dispersion liquid. Subsequently, C ₆₁ H ₂ as a charge control agent was dissolved in a water / methanol (1/1) mixed solvent, and 2 parts by weight was added to 100 parts by weight of the colored resin particles. After stirring for 1 hour, it was filtered and dried to obtain a toner.

After sufficiently mixing the toner and the carrier, the charge amount of the toner was measured by the blow-off method. The charge amount was -43.2 μC / g. In addition, a running test of 30,000 sheets was performed using a commercially available electrophotographic copying machine (Imagio 420, manufactured by Ricoh Co., Ltd.) using this toner. As a result, an image with good reproducibility of fine lines without image fog and background stain was obtained.

Example 2 A toner was obtained in the same manner as in Example 1 except that 4 parts by weight of t-butylacrylamide sulfonic acid was further added to the charged monomer of Example 1. After sufficiently mixing the toner and the carrier, the charge amount of the toner was measured by the blow-off method. As a result, the charge amount was −49.9 μC / g. Using this toner, a running test was performed on 30,000 sheets of IMAGEO 420 (manufactured by Ricoh Co., Ltd.), and as a result, an image having good fine line reproducibility without image fog and background stain was obtained.

Example 3 Carbon black MA1 was added to 40 parts by weight of styrene monomer.
00 (Mitsubishi Chemical Co., MA100) 20 parts by weight and 2,2'-azobisisobutyronitrile as a polymerization initiator (0.5 parts by weight), three-one motor drive stirring blade, cooler, gas inlet pipe, temperature It was put in a 500 ml four-necked separable flask equipped with a meter and stirred under a nitrogen stream at room temperature for 30 minutes to replace oxygen in the flask with nitrogen. Then, the mixture was stirred in a hot water bath at 70 ° C. for 6 hours at 60 rpm to obtain a graft carbon black. Next, styrene monomer 50 parts by weight n-butyl methacrylate 14.5 parts by weight 1,3-butanediol dimethacrylate 0.5 parts by weight t-butylacrylamide sulfonic acid 3 parts by weight Low molecular weight polyethylene 2 parts by weight (Mitsui Petrochemical Co., Ltd. Manufactured by Mitsui High Wax 210P) A mixture of 30 parts by weight of the above-mentioned graft carbon black was dispersed in a ball mill for 10 hours. After dissolving 1 part by weight each of 2,2'-azobisisobutyronitrile and sodium nitrite in this dispersion,
In addition to 250 parts by weight of a 2% aqueous solution of polyvinyl alcohol, 6000 with a TK homomixer (made by Tokushu Kika Co., Ltd.)
A suspension was obtained by stirring at rpm for 10 minutes.

The suspension was 500 m equipped with a three-one motor-driven stirring blade, a cooler, a gas introduction tube, and a thermometer.
It was placed in a 4-necked separable flask and stirred under a nitrogen stream at room temperature for 30 minutes to replace oxygen in the flask with nitrogen. Then, the mixture was stirred in a hot water bath at 70 ° C. for 8 hours at 90 rpm to complete the polymerization, and suspension-polymerized particles were prepared. 100 parts by weight of these particles were redispersed in a mixed solution of water / methanol = 1/1 (weight ratio) so that the solid content was 30%, 3 parts by weight of C ₆₁ H ₂ as a charge control agent was added, and the mixture was stirred and filtered. It was dried to obtain a toner.

After thoroughly mixing the toner and the carrier, the charge amount of the toner was measured by the blow-off method. As a result, the charge amount was −29.2 μC / g. Further, as a result of a running test of 30,000 sheets using this toner with IMAGEO 420, an image with good reproducibility of fine lines without image fog and background stain was obtained.

Example 4 2-Ethylhexyl acrylate and carnauba wax were used instead of n-butyl methacrylate and low molecular weight polyethylene of Example 3, respectively, except that a suspension was prepared at 60 ° C. with a TK homomixer. A toner was obtained in the same manner as in Example 1. After sufficiently mixing the toner and the carrier, the charge amount of the toner was measured by the blow-off method, and the charge amount was -33.5 μC / g. Further, as a result of performing a running test on 30,000 sheets with IMAGEO 420 using this toner, a clear image without image fog was obtained.

Example 5 Binder resin (styrene-methyl acrylate copolymer) 100 parts by weight Colorant (carbon black # 44, manufactured by Mitsubishi Carbon Co.) 0.7 parts by weight Charge control agent (C ₆₁ H ₂ ) 3 A mixture of 0.0 parts by weight was kneaded and pulverized to obtain a toner. After thoroughly mixing the toner and the carrier, the charge amount of the toner was measured by the blow-off method. The charge amount was -24.5.
It was μC / g. In addition, when an image was recorded with the imager 420 using this toner, a clear image was obtained.

Comparative Example Binder resin (styrene-methyl acrylate copolymer) 100 parts by weight Colorant (carbon black # 44, manufactured by Mitsubishi Carbon Co.) 0.7 parts by weight Charge control agent (C ₆₀ ) 3.0 parts by weight A mixture of parts was kneaded and pulverized to obtain a toner. After sufficiently mixing the toner and the carrier, the charge amount of the toner was measured by the blow-off method, and the charge amount was -21.7.
It was μC / g. In addition, when an image was recorded with the IMAGEO 420 using this toner, a clear image was obtained, but there were some places where the fine line could not be faithfully reproduced.

[0058]

According to the present invention, the saturated charge amount is stabilized, so that an image with contrast can be obtained.

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Claims (4)

[Claims] 1. An electrostatic charge image developing toner comprising a colorant, a binder resin, and a charge control agent as main components, wherein the charge control agent is a fulleroid or a mixture thereof. toner. 2. A toner for developing an electrostatic charge image, wherein the toner according to claim 1 is obtained by mixing and pulverizing. 3. A toner for developing an electrostatic charge image, wherein the toner according to claim 1 is obtained by dispersion polymerization. 4. A toner for developing an electrostatic charge image, wherein the toner according to claim 1 is obtained by suspension polymerization.