JP4832102B2 - Toner, method for producing the same, developer, and image forming method - Google Patents

Description

The present invention relates to a toner, a toner manufacturing method, a developer, and an image forming method.

  In recent years, toner particle size reduction for the purpose of improving the image quality has been promoted, but there is a problem that the fluidity of the toner decreases as the toner particle size decreases. When the fluidity of the toner is lowered, the toner is likely to aggregate, the transferability is lowered, and the resulting image is voided. Such a problem is conspicuous in a toner to which a release agent such as wax is added in order to prevent winding around the fixing roller or offset, and is particularly remarkable in a toner used in a full-color image forming apparatus. . The winding around the fixing roller means that when the toner image transferred onto the transfer material is fixed by the fixing roller or the like, the toner cannot be separated from the fixing roller but is wound around the fixing roller, and there is a claw In this case, it means a phenomenon in which the transferred object is not ejected normally by being caught on the nail. The offset means a phenomenon that the toner is transferred to the fixing roller and contaminates the transferred body when the toner image transferred onto the transferred body is fixed by a fixing roller or the like.

  Further, when the fluidity of the toner is lowered, the chance of contact with the charge imparting member is likely to be reduced, the charging uniformity is lowered, and background staining occurs in the obtained image. Such a problem is conspicuous in a toner containing a release agent such as wax, and is particularly remarkable in a toner used in a full-color image forming apparatus. The background stain means a phenomenon in which when an electrostatic latent image formed on a photoconductor is developed with toner, toner that is not sufficiently charged moves to a non-image portion and contaminates the transfer target.

  In Patent Document 1, the surface of toner particles is surface-treated with aminosilane and dimethylpolysiloxane, and an external additive comprising inorganic fine particles (A) having a polarity opposite to that of the toner and inorganic fine particles (B) having the same polarity as that of the toner. It is disclosed that a non-magnetic one-component developing toner with an agent attached reduces untransferred toner on a photoreceptor, and maintains a sufficient image density and prevents fogging of a non-image portion. However, in such a method, in a full-color image forming apparatus, it is difficult to prevent transfer failure (missing) when transferring a color overlay toner having a relatively large amount of adhesion on the intermediate transfer member to the transfer target. It is. Further, when cleaning the untransferred toner on the photoconductor, a cleaning failure occurs.

On the other hand, in order to improve the fluidity of the toner, a method of increasing the amount of external additives such as silica is known. However, the toner charge amount fluctuates due to long-term use, and scumming occurs. There is a problem of doing. If the amount of the external additive added is too large, the external additive tends to migrate to the surface of the photoconductor, and toner is accumulated on the surface of the photoconductor using the external additive as a core, and black spots are formed on the resulting image. Noise called (BS) occurs.
JP 2002-287413 A

SUMMARY OF THE INVENTION In view of the above-described problems of the prior art, the present invention provides a toner that is excellent in heat-fixing performance and image quality in an oil-less fixing process, and that can suppress the occurrence of poor cleaning and background contamination, and a method for producing the toner , and to provide an image forming method using the developer and a developer containing the toner.

The invention according to claim 1 is a toner having colored particles containing a binder resin, a colorant and a release agent , first inorganic particles, and second inorganic particles , wherein the release agent has a melting point. There is a 70 ° C. or higher 90 ° C. or less, colored particles, the content of the release agent is 10 wt% or less than 3 wt%, volume average particle size is at 4μm or 9μm or less, of the colored particles The ratio of the total weight of the first inorganic particles and the second inorganic particles to the weight is 0.04 or more and 0.05 or less, and the first inorganic particles are made of silicone oil and / or hexamethyldisilazane. Surface treatment is performed, the base point is substantially 0 μmol / g, the specific surface area is 80 m ² / g or more and 300 m ² / g or less, and the second inorganic particles include aminosilane, silicone oil, and / or Table with hexamethyldisilazane Surface treatment is performed, the base point is 50 μmol / g or more and 300 μmol / g or less, the acid point per unit specific surface area is 20 μmol / m ² or more, and the base point per unit specific surface area is 2.5 μmol / m ^2. The specific surface area is 15 m ² / g or more and 35 m ² / g or less . As a result, it is possible to provide a toner that is excellent in heat fixing performance and image quality in an oilless fixing process, and that can suppress the occurrence of poor cleaning and background contamination.

According to a second aspect of the present invention, in the toner according to the first aspect, the first inorganic particles have an average primary particle size of 10 nm or more and 20 nm or less, and the second inorganic particles have an average primary particle size. Is 55 nm or more and 80 nm or less. Thereby, fluidity | liquidity can be improved.

The invention described in claim 3 is the toner according to claim 1 or 2, wherein the binder resin is characterized by containing a port Riesuteru resin. Thereby, heat resistance, chemical resistance, mechanical properties, low-temperature fixability, and transparency can be improved.

The invention described in claim 4 is the toner according to any one of claims 1 to 3, wherein the release agent is characterized by containing a carbonaceous hydrocarbon wax. Thereby, the releasability with respect to the fixing member can be improved.
According to a fifth aspect of the present invention, in the method for producing a toner, the step of mixing the colored particles containing the binder resin, the colorant and the release agent with the first inorganic particles, the mixed colored particles, A step of mixing the first inorganic particles and the second inorganic particles, wherein the release agent has a melting point of 70 ° C. or more and 90 ° C. or less, and the colored particles have a content of the release agent of 3 The volume average particle size is 4 μm or more and 9 μm or less, and the ratio of the total weight of the first inorganic particles and the second inorganic particles to the weight of the colored particles is 0.04. It is 0.05 or less, the first inorganic particles are surface-treated with silicone oil and / or hexamethyldisilazane, the base point is substantially 0 μmol / g, and the specific surface area is 80 m ² / g to 300 m ² / g, the second inorganic particles Is surface-treated with aminosilane and silicone oil and / or hexamethyldisilazane, the base point is 50 μmol / g or more and 300 μmol / g or less, and the acid point per unit specific surface area is 20 μmol / m ² or more. The base point per unit specific surface area is 2.5 μmol / m ² or more, and the specific surface area is 15 m ² / g or more and 35 m ² / g or less. Accordingly, it is possible to provide a toner manufacturing method that is excellent in heat fixing performance and image quality in an oilless fixing process, and that can suppress the occurrence of poor cleaning and background contamination.

A sixth aspect of the present invention is characterized in that the developer contains the toner according to any one of the first to fourth aspects. As a result, it is possible to provide a developer that has excellent heat fixing performance and image quality in an oilless fixing process, and can suppress the occurrence of poor cleaning and background contamination.

According to a seventh aspect of the present invention, in the image forming method, the step of forming a toner image by developing the electrostatic charge image formed on the electrostatic charge image carrier using the developer according to the sixth aspect. When, characterized in that it has a step of transferring the toner image to a transfer member, the toner image transferred to said transfer member, a step of heat-fixing by using a roller having a heating device. Accordingly, it is possible to provide an image forming method that is excellent in heat fixing performance and image quality in an oilless fixing process and that can suppress the occurrence of poor cleaning and background contamination.

According to an eighth aspect of the present invention, in the image forming method, a step of forming a toner image by developing the electrostatic charge image formed on the electrostatic charge image carrier using the developer according to the eighth aspect. When, for the step of transferring the toner image to a transfer member, the toner image transferred to said transfer member, characterized by having a step of heat-fixing by using an oil-less fixing device. Accordingly, it is possible to provide an image forming method that is excellent in heat fixing performance and image quality in an oilless fixing process and that can suppress the occurrence of poor cleaning and background contamination.

According to the present invention, a toner that is excellent in heat-fixing performance and image quality in an oil-less fixing process and that can suppress the occurrence of poor cleaning and background stains, a method for producing the toner, and a developer containing the toner And an image forming method using the developer.

  Next, the best mode for carrying out the present invention will be described.

  The toner of the present invention is obtained by adding an external additive to colored particles containing a binder resin, a colorant and a release agent, and the melting point of the release agent is 70 to 90 ° C. Furthermore, the product of the volume average particle diameter of the colored particles and the weight ratio of the external additive to the colored particles is 15 to 40 μm ·% by weight. When this product is smaller than 15 μm · weight%, the transferability is lowered, and the resulting image is hollowed out. In particular, when a full-color image is formed and when a release agent is included in the colored particles, the occurrence of voids becomes significant. On the other hand, if the product is larger than 40 μm · weight%, the fixing property is lowered, and the fixing strength of the obtained image is insufficient. In particular, when heat fixing is performed using an oilless fixing device that does not use oil, the fixing strength is significantly reduced. Note that transferability means ease of transfer when a toner image formed on the surface of a photosensitive member is transferred to a transfer target, and the toner image on the surface of the photosensitive member is transferred to an intermediate transfer member such as an intermediate transfer belt. In the case where the toner image on the intermediate transfer member is transferred to the transfer target after the transfer, it includes the ease of transfer from the photosensitive member to the intermediate transfer member and the transferability from the intermediate transfer member to the transfer target. Means.

Furthermore, in the present invention, the external additive includes inorganic particles A having a base point of substantially 0, a base point of 50 to 300 μmol / g, an acid point per unit specific surface area of 20 μmol / m ² or more, and a unit ratio. Inorganic particles B having a base point per surface area of 2.5 μmol / m ² or more are contained, and the average primary particle size of the inorganic particles A is smaller than the average primary particle size of the inorganic particles B. The external additive may further contain inorganic particles other than the inorganic particles A and the inorganic particles B. If the base point of the inorganic particles B is less than 50 μmol / g, the chargeability is lowered, the charge amount distribution is likely to be widened, and background staining occurs. In particular, when the content of the release agent in the colored particles is large in order to secure the fixing separation property when heat-fixing using an oil-less fixing device, the occurrence of scumming becomes significant. In addition, if the base point of the inorganic particles B is greater than 300 μmol / g, the contribution of the colored particles to charging is increased, which is not preferable. Further, when the base point when the acid point is 20 [mu] mol / m ² less than and unit specific per surface area per unit specific surface area of the inorganic particles B is 2.5 .mu.mol / m ² less than the charging property at the time of the durability is lowered , Soiling occurs.

The acid point is a measurement condition using a gas adsorption amount measuring device AUTOSORB-1-C (manufactured by Quantachrome) on the powder surface. Refrigerant (temperature): 25 ° C.
Pretreatment conditions: vacuum degassing (150 ° C., 12 hours)
Use cell: 9mmφ (OD) short large cell + filter Measurement pressure range: 80-800mmHg
It means a value obtained by converting the chemical adsorption amount of ammonia gas measured in the chemical adsorption mode by the gas adsorption method into the number of molecules. Moreover, a base point means the value which converted the chemical adsorption amount of the carbon dioxide gas measured by the same method into the number of molecules. In addition, an acid point and a base point can be calculated | required by applying an extrapolation method to 7 points | pieces of 300-800 mmHg of a composite isotherm among chemical adsorption isotherms (refer FIG. 1). In addition, an acid point and a base point can be calculated | required using the same principle rule as the above, and measuring apparatuses other than the above can be used.

In the present invention, the BET specific surface area of the inorganic particles B is preferably 15 to 35 m ² / g. When the BET specific surface area is smaller than 15 m ² / g, the effect of the inorganic particles B is hardly exhibited, and when the addition amount is increased, the fixability may be lowered. On the other hand, if the BET specific surface area is larger than 35 m ² / g, when the toner remaining on the photoreceptor after the transfer is cleaned, the damming effect is reduced, and vertical stripe noise may occur in the image.

Moreover, it is preferable that the BET specific surface area of the inorganic particle A is 80-300 m < ² > / g. When the BET specific surface area is less than 80 m ² / g, the toner has insufficient fluidity, and scumming may easily occur. Further, when the BET specific surface area is larger than 300 m ² / g, aggregation may easily occur.

  The BET specific surface area can be measured by a multi-point method using nitrogen gas, using a gas adsorption amount measuring device AUTOSORB-1-C (manufactured by Quantachrome).

  In the present invention, the average primary particle size of the inorganic particles A and the inorganic particles B is preferably 5 nm or more and 150 nm or less. When the average primary particle size is less than 5 nm, the toner tends to be buried in the surface of the toner, resulting in poor charging during durability, and when it exceeds 150 nm, the fluidity may be insufficient.

  In the present invention, the type of external additive is not particularly limited, and examples thereof include silica, titania, alumina, strontium titanate, tin oxide, and zinc oxide. Among these, silica is preferable in consideration of fluidity and chargeability. External additives include silane coupling agents, titanate coupling agents, silicone oils, silicone varnishes and other conventionally used hydrophobizing agents, fluorinated silane coupling agents, fluorinated silicone oils, amino groups and 4 Surface treatment is preferably performed by a known method using a treatment agent such as a coupling agent having a quaternary ammonium salt or a modified silicone oil. In order to control the acid point and base point of the external additive, the surface treatment may be performed with such a treatment agent, and aminosilane, silicone oil, HMDS, or the like is preferably used alone or in combination of two or more.

  As a method for producing the toner of the present invention, a conventionally known method such as a pulverization method, an emulsion polymerization association method, or a suspension polymerization method can be used.

  When using the emulsion polymerization association method, a vinyl resin dispersion in which a release agent obtained by applying a method such as miniemulsion polymerization to at least a vinyl monomer in which a release agent is dissolved or dispersed is added. The colored particles can be isolated by associating and fusing together with the pigment dispersion and the like, and then washing, filtering and drying according to a known method.

  When the pulverization method is used, according to a conventionally known method, at least a binder resin to which a release agent is added, a binder resin to which no release agent is added, and a colorant are mechanically mixed, and then melt-kneaded. Grind and classify. In addition, when mechanically mixing or melt-kneading, it is preferable that the powder removed by classification is returned and reused. What is necessary is just to carry out on normal conditions using a normal mixer etc. which have a stirring blade, when mixing mechanically. As a melt-kneader for melting and kneading a mixture obtained by mechanical mixing, a uniaxial, biaxial continuous kneader, or a batch kneader using a roll mill can be used. Machine (Kobe Steel Co., Ltd.), TEM type extruder (Toshiba Machine Co., Ltd.), twin screw extruder (K. C. K.K.), PCM type twin screw extruder (Ikegai Iron Works Co., Ltd.), Konider ( And the like). The melt kneading is preferably performed under conditions that do not cut the molecular chain of the binder resin. At this time, if the melt kneading temperature is too lower than the softening point of the binder resin, the molecular chain may be severely cut, and if too high, the dispersion may not proceed. When the melt-kneaded kneaded product is pulverized, it is preferable to pulverize after coarse pulverization. At this time, a method of pulverizing by colliding with a collision plate in a jet stream, a method of pulverizing particles by colliding with each other in a jet stream, a method of pulverizing with a narrow gap between a mechanically rotating rotor and a stator, etc. are used. It is preferable. When the pulverized pulverized product is classified, colored particles are obtained by classification in an air stream by centrifugal force or the like.

  In the present invention, the binder resin is not particularly limited as long as it is generally used as a binder resin for toner, and is not limited to polyester resin, polyurethane resin, polyurea resin, epoxy resin, vinyl resin, and these resins. A polymer etc. are mentioned. In addition, binder resin can be used individually or in mixture of 2 or more types.

  Examples of polyester resins include polycondensates of polyols and polycarboxylic acids.

  Examples of the polyol include a diol and a trivalent or higher polyol, and it is preferable to use a diol alone or a mixture of a diol and a small amount of a trivalent or higher polyol. Diols include alkylene glycols such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol; diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene Alkylene ether glycols such as glycol, polypropylene glycol and polytetramethylene ether glycol; alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; bisphenols such as bisphenol A, bisphenol F and bisphenol S; Alkylene oxide adducts of cyclic diols such as ethylene oxide, propylene oxide and butylene oxide; ethylene oxides and propylenes of the above bisphenols N'okishido, alkylene oxide adduct of butylene oxide. Among them, alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols are preferable, and alkylene oxide adducts of bisphenols and mixtures thereof with alkylene glycols having 2 to 12 carbon atoms are particularly preferable. Examples of the trihydric or higher polyol include 3 to 8 or more polyhydric aliphatic alcohols such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, and the like; More than polyhydric phenols; and alkylene oxide adducts of trihydric or higher polyphenols.

  Examples of the polycarboxylic acid include dicarboxylic acid and trivalent or higher polycarboxylic acid, and dicarboxylic acid alone or a mixture of dicarboxylic acid and a small amount of trivalent or higher polycarboxylic acid is preferable. Dicarboxylic acids include alkylene dicarboxylic acids such as succinic acid, adipic acid and sebacic acid; alkenylene dicarboxylic acids such as maleic acid and fumaric acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid and naphthalenedicarboxylic acid. Can be mentioned. Of these, alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms are preferable. Examples of the trivalent or higher polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms such as trimellitic acid and pyromellitic acid. In addition, as polycarboxylic acid, you may use dicarboxylic acid and the acid anhydride of polycarboxylic acid more than trivalence, or lower alkyl esters, such as methyl ester, ethyl ester, and isopropyl ester.

The vinyl resin is a homopolymer or copolymer of a vinyl monomer. Examples of the vinyl monomer include the following compounds (1) to (10).
(1) Vinyl hydrocarbons As aliphatic vinyl hydrocarbons, alkenes such as ethylene, propylene, butene, isobutylene, pentene, heptene, diisobutylene, octene, dodecene, octadecene, and other α-olefins; butadiene , Alkanedienes such as isoprene, 1,4-pentadiene, 1,6-hexadiene, 1,7-octadiene.

  Cyclohexene, (di) cyclopentadiene, vinylcyclohexene, ethylidenebicycloheptene and other (di) cycloalkenes and (di) cycloalkadienes; terpenes such as pinene, limonene and indene Is mentioned.

As aromatic vinyl hydrocarbons, α-methylstyrene, vinyltoluene, 2,4-dimethylstyrene, ethylstyrene, isopropylstyrene, butylstyrene, phenylstyrene, cyclohexylstyrene, benzylstyrene, crotylbenzene, divinylbenzene, divinyl Styrene such as toluene, divinylxylene, and trivinylbenzene and alkyl, cycloalkyl, aralkyl and / or alkenyl substituted products thereof; vinyl naphthalene and the like.
(2) Vinyl monomers having a carboxyl group and salts thereof As vinyl monomers having a carboxyl group, (meth) acrylic acid, (anhydrous) maleic acid, monoalkyl maleate, fumaric acid, monoalkyl fumarate, crotonic acid , Itaconic acid, itaconic acid monoalkyl, itaconic acid glycol monoether, citraconic acid, citraconic acid monoalkyl, cinnamic acid, etc., C3-C30 unsaturated monocarboxylic acids, unsaturated dicarboxylic acids, and anhydrides and carbon numbers thereof 1-24 monoalkyl esters.

Examples of salts of vinyl monomers having a carboxyl group include alkali metal salts such as sodium salts and potassium salts; alkaline earth metal salts such as calcium salts and magnesium salts; ammonium salts, amine salts and quaternary ammonium salts. .
(3) Vinyl monomers having sulfonic acid groups, sulfates of vinyl monomers, and salts thereof Examples of vinyl monomers having sulfonic acid groups include vinyl sulfonic acid, (meth) allyl sulfonic acid, methyl vinyl sulfonic acid, and styrene. Alkene sulfonic acids having 2 to 14 carbon atoms such as sulfonic acid and α-methylstyrene sulfonic acid and alkyl substituted products thereof having 2 to 24 carbon atoms; sulfopropyl (meth) acrylate, 2-hydroxy-3- (meth) acryloyl Oxypropylsulfonic acid, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid, 2- (meth) acryloyloxyethanesulfonic acid, 3- (meth) acryloyloxy-2-hydroxypropanesulfonic acid, 2- (Meth) acrylamido-2-methylpropanesulfone 3- (meth) acrylamido-2-hydroxy propane (meth) acrylic acid sulfo (hydroxy) alkyl and (meth) acrylamide sulfonic acid, alkyl (having from 3 to 18 carbon atoms) allyl sulfosuccinate and the like.

  As a sulfuric ester of a vinyl monomer, a poly (n = 2-30) oxyalkylene (ethylene, propylene, butylene: single, random or block) such as poly (n = 5-15) oxypropylene monomethacrylate sulfate ) Mono (meth) acrylate sulfate ester and the like.

Examples of salts of vinyl monomers having a sulfonic acid group and sulfates of vinyl monomers include alkali metal salts such as sodium salts and potassium salts; alkaline earth metal salts such as calcium salts and magnesium salts; ammonium salts, amine salts, A quaternary ammonium salt etc. are mentioned.
(4) Vinyl monomer having phosphoric acid group and salt thereof As vinyl monomer having phosphoric acid group, (meth) acryloyloxy such as 2-hydroxyethyl (meth) acryloyl phosphate and phenyl-2-acryloyloxyethyl phosphate Alkylphosphoric acid monoesters; (meth) acryloyloxyalkyl (C 1-24) phosphonic acids such as 2-acryloyloxyethylphosphonic acid.

Examples of salts of vinyl monomers having a phosphate group include alkali metal salts such as sodium salts and potassium salts; alkaline earth metal salts such as calcium salts and magnesium salts; ammonium salts, amine salts and quaternary ammonium salts. It is done.
(5) Vinyl monomer having a hydroxyl group Examples of the vinyl monomer having a hydroxyl group include hydroxystyrene, N-methylol (meth) acrylamide, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, polyethylene glycol mono (Meth) acrylate, (meth) allyl alcohol, crotyl alcohol, isocrotyl alcohol, 1-buten-3-ol, 2-buten-1-ol, 2-butene-1,4-diol, propargyl alcohol, 2 -Hydroxyethyl propenyl ether, sucrose allyl ether, etc. are mentioned.
(6) Nitrogen-containing vinyl monomer As the vinyl monomer having an amino group, aminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, t-butylaminoethyl methacrylate N- (aminoethyl) (meth) acrylamide, (meth) allylamine, morpholinoethyl (meth) acrylate, 4-vinylpyridine, 2-vinylpyridine, crotylamine, N, N-dimethylaminostyrene, α-acetaminoacrylic Acid methyl, vinylimidazole, N-vinylpyrrole, N-vinylthiopyrrolidone, N-allylphenylenediamine, aminocarbazole, aminothiazole, aminoindole, aminopyrrole, aminoimidazole, aminomercaptothiazole, etc. That.

  Examples of salts of vinyl monomers having an amino group include alkali metal salts such as sodium salts and potassium salts; alkaline earth metal salts such as calcium salts and magnesium salts; ammonium salts, amine salts and quaternary ammonium salts. .

  Examples of vinyl monomers having an amide group include (meth) acrylamide, N-methyl (meth) acrylamide, N-butyl acrylamide, diacetone acrylamide, N-methylol (meth) acrylamide, and N, N′-methylenebis (meth) acrylamide. Cinnamic acid amide, N, N-dimethylacrylamide, N, N-dibenzylacrylamide, N-methyl-N-vinylacetamide, N-vinylpyrrolidone and the like.

  Examples of the vinyl monomer having a nitrile group include (meth) acrylonitrile, cyanostyrene, cyanoacrylic acid and the like.

  Quaternary ammonium salt vinyl monomers include tertiary amino groups such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylamide, diethylaminoethyl (meth) acrylamide, diallylamine and the like. Quaternized products of vinyl monomers having As the quaternizing agent, methyl chloride, dimethyl sulfate, benzyl chloride, dimethyl carbonate or the like can be used.

Nitrostyrene etc. are mentioned as a vinyl-type monomer which has a nitro group.
(7) Vinyl monomer having an epoxy group Examples of the vinyl monomer having an epoxy group include glycidyl (meth) acrylate and tetrahydrofurfuryl (meth) acrylate.
(8) Vinyl monomer having a halogen group Examples of vinyl monomers having a halogen group include vinyl chloride, vinyl bromide, vinylidene chloride, allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluorostyrene, Examples include chloroprene.
(9) Vinyl ester, vinyl (thio) ether, vinyl ketone, vinyl sulfone As vinyl esters, vinyl acetate, vinyl propionate, vinyl butyrate, diallyl phthalate, diallyl adipate, isopropenyl acetate, vinyl methacrylate, 4-vinyl Methyl benzoate, cyclohexyl methacrylate, benzyl methacrylate, phenyl (meth) acrylate, vinyl methoxyacetate, vinyl benzoate, ethyl α-ethoxyacrylate; methyl (meth) acrylate, ethyl (meth) acrylate, (meth ) Propyl acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate, hexadecyl (meth) acrylate, heptadecyl (meth) acrylate, eicosyl (meth) acrylate, etc. (Meta) Alkyl acrylate (1 to 50 carbon atoms); dialkyl fumarate, dialkyl maleate (two alkyl groups are linear, branched or alicyclic having 2 to 8 carbon atoms); polyethylene glycol (molecular weight 300) Poly (meth) acrylate, polypropylene glycol (molecular weight 500) monoacrylate, (meth) acrylic acid ester of methanol 10 mol adduct of methanol, (meth) acrylic acid ester of 30 mol adduct of ethylene oxide of lauryl alcohol, etc. Vinyl monomers having an alkylene glycol chain; ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, polyethylene Rikoruji (meth) poly polyhydric alcohols acrylate (meth) acrylate.

  As vinyl (thio) ether, diallyloxyethane, triallyloxyethane, tetraallyloxyethane, tetraallyloxypropane, tetraallyloxybutane, tetramethallyloxyeta, vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, Vinyl butyl ether, vinyl (2-ethylhexyl) ether, vinyl phenyl ether, vinyl (2-methoxyethyl) ether, methoxybutadiene, vinyl (2-butoxyethyl) ether, 3,4-dihydro-1,2-pyran, 2- Examples include butoxy-2′-vinyloxydiethyl ether, vinyl (2-ethylmercaptoethyl) ether, acetoxystyrene, phenoxystyrene, and the like.

  Examples of the vinyl ketone include vinyl methyl ketone, vinyl ethyl ketone, and vinyl phenyl ketone.

Examples of the vinyl sulfone include divinyl sulfide, p-vinyl diphenyl sulfide, vinyl ethyl sulfide, vinyl ethyl sulfone, divinyl sulfone, and divinyl sulfoxide.
(10) Other vinyl monomers Examples of other vinyl monomers include isocyanatoethyl (meth) acrylate, m-isopropenyl-α, α-dimethylbenzyl isocyanate.

  The vinyl monomer copolymer can be obtained by copolymerizing two or more of the vinyl monomers (1) to (10). For example, a styrene- (meth) acrylate copolymer , Styrene-butadiene copolymer, (meth) acrylic acid-acrylic ester copolymer, styrene-acrylonitrile copolymer, styrene-maleic anhydride copolymer, styrene- (meth) acrylic acid copolymer, styrene- (Meth) acrylic acid-divinylbenzene copolymer, styrene-styrenesulfonic acid- (meth) acrylic acid ester copolymer, and the like.

  In the present invention, the binder resin may be a polyester resin and a vinyl resin, a polyester resin or a block copolymer or a graft copolymer of vinyl resins. In order to obtain a block copolymer or a graft copolymer, a known method may be used. For example, in the presence of a polyester resin having a vinyl group, an allyl group, a (meth) acryloyl group, etc. A method for polymerizing monomers, a method for polycondensing polyols and polycarboxylic acids in the presence of vinyl resins having hydroxyl groups, carboxyl groups, amino groups, etc., vinyl monomers, polyols, polycarboxylic acids and carboxyl groups, hydroxyl groups Examples include a method in which polymerization of a vinyl monomer and polycondensation of a polyol and a polycarboxylic acid are performed in parallel or sequentially in the presence of a vinyl monomer having at least one of a group, an amino group and an epoxy group.

  In the present invention, as a method for producing a binder resin to which a release agent is added, a method of polymerizing a monomer (polyol, polycarboxylic acid, vinyl monomer) in which the release agent is dissolved or dispersed, a release agent, and Examples thereof include a method of removing the solvent and a method of melting and kneading the release agent and the binder resin in a state where the binder resin is dissolved in the solvent. In the polymerization, a block copolymer or a graft copolymer may be generated. In order to disperse the release agent uniformly in the binder resin and to improve the inclusion property of the release agent, it is preferable to crosslink the binder resin.

  The content of the release agent in the binder resin to which the release agent is added is usually 6 to 30% by weight, preferably 7 to 20% by weight, and more preferably 8 to 25% by weight. When the content of the release agent is less than 6% by weight, the amount of the release agent that oozes out from the binder resin at the time of fixing decreases, and the fixing separation property may be lowered. On the other hand, when the content of the release agent exceeds 30% by weight, the amount of the release agent exposed on the surface increases, and the developing member and the photoreceptor may be contaminated.

  In the present invention, the softening point T1 / 2 of the binder resin to which the release agent is added is usually 120 to 150 ° C, preferably 120 to 140 ° C. When T1 / 2 is lower than 120 ° C., the encapsulating property of the release agent is lowered, and the release agent may be easily exposed on the surface of the toner. On the other hand, if T1 / 2 is higher than 150 ° C., the meltability of the toner is lowered, and the fixing performance may be lowered.

  In the present invention, T1 / 2 of the binder resin to which no release agent is added is usually 100 to 130 ° C, preferably 105 to 120 ° C. When T1 / 2 is lower than 100 ° C., the toners are fused with each other in a high-temperature and high-humidity environment, and the storage stability may be lowered. When T1 / 2 is higher than 130 ° C., the melting property of the toner is lowered and fixing is performed. Performance may be reduced. In addition, T1 / 2 of the binder resin to which no release agent is added is usually 3 ° C. or more lower than the binder resin to which the release agent is added, preferably 5 ° C. or more, preferably 7 ° C. or more. More preferably, it is low. Thereby, the fixing strength can be improved.

  In addition, T1 / 2 can be measured using a flow tester CFT-500D (manufactured by Shimadzu Corporation), the extrusion port has a diameter of 0.5 mm, a depth of 1 mm, and a heating rate of 3 ° C./min. The load applied to the sample is preferably set to 30 kgf.

  The acid value of the toner of the present invention is preferably 10 to 40 mgKOH / g. When the acid value is lower than 10 mgKOH / g, the fixing strength may be lowered, and when it exceeds 40 mgKOH / g, the fluctuation in performance due to the environment may become remarkable.

The acid value can be measured according to JIS K-0070. The specific operation procedure is as follows. In a 300 ml beaker, 150 ml of a 4: 1 volume ratio of toluene-ethanol mixture is added to sample W [g] and dissolved. Next, it titrates with a 0.1M KOH ethanol solution using a potentiometric titrator. For example, automatic titration can be performed using a potentiometric titrator AT-400 (winworkstation) (manufactured by Kyoto Electronics Co., Ltd.) and an ABP-410 electric burette. Further, the blank is titrated in the same manner. At this time, assuming that the titer of the sample is S [ml] and the titer of the blank is B [ml], the acid value is represented by the formula: acid value (mgKOH / g) = {(SB) × f × 5.61 } / W
Can be calculated. Note that f is a factor of a 0.1 M KOH ethanol solution.

  In the present invention, it is preferable that the release agent has a low polarity because it is excellent in releasability with respect to a fixing member such as a roller. Examples of such a release agent include hydrocarbon waxes.

  Hydrocarbon waxes are composed of carbon atoms and hydrogen atoms. For example, polyolefin waxes such as polyethylene, polypropylene and ethylene-propylene copolymers, petroleum waxes such as paraffin wax and microcrystalline wax, synthetic waxes such as Fischer-Tropsch wax, etc. Is mentioned. Among these, polyethylene wax, paraffin wax and Fischer-Tropsch wax are preferable, polyethylene wax and paraffin wax are more preferable, and paraffin wax is particularly preferable.

  In this invention, melting | fusing point of a mold release agent is the endothermic peak at the time of the temperature rising measured with a differential scanning calorimeter (DSC), and is 70-90 degreeC normally. When the melting point is higher than 90 ° C., the release agent may not be sufficiently melted in the fixing process, and the releasability of the fixing member may be deteriorated. On the other hand, when the melting point is lower than 70 ° C., the toners are fused with each other in a high temperature and high humidity environment, and the storage stability may be lowered. Further, in order to improve the fixing separation property at a low temperature, the melting point of the release agent is preferably 70 to 85 ° C, more preferably 70 to 80 ° C.

  Moreover, it is preferable that the half value width of the endothermic peak of the release agent at the time of temperature rise measured by a differential scanning calorimeter (DSC) is 7 ° C. or less. When the half-value width of the endothermic peak is larger than 7 ° C., the release agent melts from a low temperature range, and the storage stability of the toner may be lowered.

  As the differential scanning calorimeter (DSC), DSC6200 (manufactured by Seiko Instruments Inc.) can be used. After the temperature is raised to 200 ° C., the sample cooled to 0 ° C. at a temperature lowering rate of 10 ° C./min is raised. It is preferable to measure at a temperature rate of 10 ° C./min.

  In the present invention, the content of the release agent in the colored particles is 3 to 10% by weight, preferably 4 to 8% by weight, and more preferably 4 to 6.5% by weight. When the content of the release agent is less than 3% by weight, the amount of the release agent that exudes between the toner and the fixing member becomes insufficient in the fixing process, and the releasability to the fixing member may be reduced. . On the other hand, when the content of the release agent exceeds 10% by weight, the amount of the release agent exposed on the surface of the toner increases, and the fluidity of the toner decreases, so that the developing unit from the photoconductor and the photoconductor Transfer efficiency to the transfer target may be reduced. Further, the release agent on the surface of the toner may be detached, and the developing member and the photoreceptor may be contaminated.

  In the present invention, known dyes and pigments can be used as the colorant. For example, carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow Iron oxide, ocher, yellow lead, titanium yellow, polyazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast Yellow (5G, R), Tartrazine Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL, Isoindolinone Yellow, Bengala, Red Dan, Lead Zhu, Cadmium Red, Cadmium Mercury Red, Antimon Zhu, Permanent Red 4R, Para Red, Phi Sayred, p- Rollo-o-nitroaniline red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carnmin BS, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, alizarin lake, thioindigo red B, thioindigo maroon, oil red, quinacridone red, Lazolone Red, Polyazo Red, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indance Ren blue (RS, BC), indigo, ultramarine, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, viridian, emerald green , Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Gree Rake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, litbon and mixtures thereof. The content of the colorant in the toner is usually 1 to 15% by weight, and preferably 3 to 10% by weight.

  In the present invention, the colorant can also be used as a master batch combined with a resin. Resin used for masterbatch or binder resin kneaded with masterbatch includes rosin resin, modified rosin resin, terpene resin, aliphatic or alicyclic hydrocarbon resin in addition to the above-mentioned polyester resin and vinyl resin , Aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like, and can be used alone or in combination of two or more.

  In the present invention, the colored particles may further contain a charge control agent as required. As the charge control agent, known ones can be used. For example, nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, molybdate chelate pigments, rhodamine dyes, alkoxy amines, quaternary ammonium Examples thereof include salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus simple substances or compounds, tungsten simple substances or compounds, fluorosurfactants, salicylic acid metal salts, metal salts of salicylic acid derivatives, and the like. Specifically, Bontron 03 of nigrosine dye, Bontron P-51 of quaternary ammonium salt, Bontron S-34 of metal-containing azo dye, E-82 of oxynaphthoic acid metal complex, E- of salicylic acid metal complex 84, E-89 of phenol-based condensate (above, manufactured by Orient Chemical Co., Ltd.), TP-302, TP-415 of molybdenum complex of quaternary ammonium salt (above, manufactured by Hodogaya Chemical Co., Ltd.), quaternary ammonium salt Copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (above, manufactured by Hoechst), LRA-901, boron complex LR-147 (Japan) Carlit), copper phthalocyanine, perylene, quinacridone, Examples thereof include azo pigments and other polymer compounds having a sulfonic acid group, a carboxyl group, a quaternary ammonium salt, and the like.

  In the present invention, the amount of charge control agent added is determined by the type of binder resin, the presence or absence of additives used as necessary, and the toner production method including the dispersion method. Although not limited, it is preferably 0.1 to 10% by weight, and more preferably 0.2 to 5% by weight with respect to the binder resin. When the addition amount of the charge control agent exceeds 10% by weight, the chargeability of the toner is increased, the effect of the main charge control agent is reduced, the electrostatic attraction to the developing roller is increased, and the flowability of the developer is lowered. However, the image density may decrease. These charge control agents may be melt-kneaded with the master batch and the binder resin, or may be externally added and mixed with a Henschel mixer or the like.

  In the present invention, the colored particles may further contain a dispersant in order to disperse the release agent. The dispersant is not particularly limited, and a known one can be used, and a block copolymer or graft copolymer having a unit highly compatible with the release agent and a unit highly compatible with the binder resin. , Ethylene, propylene, butene, styrene, α-methylstyrene, and other unsaturated hydrocarbons, and acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, and other α, β-unsaturated carboxylic acids Alternatively, an ester or anhydride copolymer thereof, a block copolymer of vinyl resin and polyester resin, or a graft copolymer may be used. Examples of the unit having high compatibility with the release agent include a long chain alkyl group having 12 or more carbon atoms and a polymer obtained by homopolymerization or copolymerization of ethylene, propylene, butene, butadiene and the like. Examples of the unit highly compatible with the adhesion resin include polyester resin and vinyl resin.

  The weight ratio of the dispersant to the release agent is usually from 0.1 to 5, and preferably from 0.3 to 2.5. If the weight ratio is less than 0.1, the effect of dispersing the release agent is not observed, and if it exceeds 5, the exudation of the release agent in the fixing process is suppressed, and the fixing separation property may be lowered.

  In the present invention, the volume average particle diameter of the colored particles is preferably 4 to 9 μm.

  The particle size of the colored particles can be measured by a Coulter counter method. Examples of the particle size distribution measuring apparatus by the Coulter Counter method include Coulter Counter TA-II, Coulter Multisizer II, and Coulter Multisizer III (manufactured by Coulter, Inc.). A specific measurement method will be described below. First, 0.1 to 5 ml of a surfactant such as an alkylbenzene sulfonate is added as a dispersant to 100 to 150 ml of the electrolytic solution. Here, the electrolytic solution is an aqueous solution of 1 wt% primary sodium chloride, and for example, ISOTON-II (manufactured by Coulter, Inc.) can be used. Next, add 2-20 mg of the sample as solids. The dispersion liquid in which the sample is dispersed is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and then a volume distribution and a number distribution are obtained by measuring the volume and number of colored particles using a 100 μm aperture. . From the obtained distribution, the volume average particle diameter and the number average particle diameter of the colored particles can be obtained.

  The toner of the present invention preferably has an average circularity of 0.96 to 1.00, more preferably 0.98 to 1.00. Thereby, a reproducible and high-definition image can be formed with an appropriate density. As a method for measuring the average circularity of toner, a suspension containing toner is passed through an imaging unit detection zone on a flat plate, and a particle image is optically detected and analyzed by a CCD camera. A method is mentioned. The circularity is a value obtained by dividing the perimeter of an equivalent circle having the same area as the projected area obtained by this method by the perimeter of the actual particle.

  The average circularity can be measured using a flow particle image analyzer FPIA-2000. As a specific measurement method, 0.1 to 0.5 ml of a surfactant such as alkylbenzene sulfonate is added as a dispersant to 100 to 150 ml of water from which impure solids have been removed in advance. Add about 1-0.5g. Next, the dispersion liquid in which the sample is dispersed is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, the concentration of the dispersion liquid is set to 3000 to 10,000 pieces / μl, and then the average circularity is measured.

  The developer of the present invention contains the toner of the present invention. The developer of the present invention may be either a non-magnetic one-component developer or a magnetic one-component developer, or a two-component developer further containing a carrier.

  The image forming method of the present invention comprises a step of forming a toner image by developing an electrostatic charge image formed on an electrostatic charge image carrier using the developer of the present invention, and transferring the toner image to a transfer target. And a step of heating and fixing the toner image transferred to the transfer target. When heat fixing, a roller having a heating device may be used, or an oilless fixing device may be used.

Next, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples. In the examples, all parts mean parts by weight.
(Manufacture of resin H)
In the dropping funnel, 600 g of styrene, 110 g of butyl acrylate and 30 g of acrylic acid as a vinyl monomer, and 30 g of dicumyl peroxide as a polymerization initiator were added. Polyoxypropylene (n = 2.2) -2,2-bis (4-hydroxyphenyl) as a polyol in a 5-liter four-necked flask equipped with a thermometer, stainless steel stirrer, flow-down condenser and nitrogen inlet tube 1230 g of propane, 290 g of polyoxyethylene (n = 2.2) -2,2-bis (4-hydroxyphenyl) propane, 250 g of isododecenyl succinic anhydride, 310 g of terephthalic acid, 1,2,4-benzene as polycarboxylic acid 180 g of tricarboxylic acid anhydride, 7 g of dibutyltin oxide as an esterification catalyst, paraffin wax (melting point: 73.3 ° C., half-width of endothermic peak at the time of temperature rise measured by a differential scanning calorimeter as a release agent, 3.9 460 g) and stirring at 160 ° C. under a nitrogen atmosphere using a mantle heater While, was added dropwise over one hour a mixture of the vinyl monomer and a polymerization initiator from the dropping funnel. After aging the addition polymerization at 160 ° C. for 2 hours, the temperature was raised to 230 ° C. for polycondensation. The degree of polymerization was tracked by measuring the softening point T1 / 2 using a flow tester, and when the desired value was reached, the reaction was terminated and Resin H was obtained.
(Manufacture of resin L)
Polyoxypropylene (n = 2.2) -2,2-bis (4-hydroxyphenyl) as a polyol in a 5-liter four-necked flask equipped with a thermometer, stainless steel stirrer, flow-down condenser and nitrogen inlet tube 2210 g of propane, 850 g of terephthalic acid and 120 g of 1,2,4-benzenetricarboxylic acid anhydride as polycarboxylic acid, 0.5 g of dibutyltin oxide as an esterification catalyst, and 230 ° C. in a nitrogen atmosphere using a mantle heater The mixture was heated to polycondensation. The degree of polymerization was tracked by measuring the softening point T1 / 2 using a flow tester, and when the desired value was reached, the reaction was terminated and Resin L was obtained.
(Manufacture of external additives)
External additives 1 to 14 were obtained by subjecting silica to surface treatment with the addition amount of the surface treatment agent shown in Table 1. Table 2 shows the physical properties of the obtained external additive.

なお、疎水化度は、メタノールウエッタビリティ法により測定した。具体的には、外添剤を分散した水中にメタノールを滴下し、外添剤を全て湿潤するために必要なメタノールの重量を測定した。このとき、水とメタノールの総重量に対するメタノールの重量の比を疎水化度とした。

The degree of hydrophobicity was measured by the methanol wettability method. Specifically, methanol was dropped into water in which the external additive was dispersed, and the weight of methanol necessary to wet all the external additive was measured. At this time, the ratio of the weight of methanol to the total weight of water and methanol was defined as the degree of hydrophobicity.

In addition, 0.1 g of a mixture obtained by placing 0.1 g of an external additive and 50 g of an iron powder carrier in a 75 ml glass container and shaking for 5 minutes with a turbula mixer was measured for the charge amount, and the blow-off charge amount was measured. The value after nitrogen blowing for 1 minute with an apparatus TB-200 type (manufactured by Toshiba Chemical Co., Ltd.) was measured.
Example 1
30 parts of resin H, 70 parts of resin L, 1 part of a metal salt of a salicylic acid derivative as a charge control agent and 2.5 parts of C.I. I. Pigment Blue 15: 3 was mixed with a blender, kneaded with a twin screw extruder, and cooled. Further, by pulverizing and classifying, cyan colored particles having a volume average particle diameter of 7.0 μm were obtained. At this time, the content of the release agent in the colored particles was 4.5% by weight.

  Using Henschel mixer FM20C / I (Mitsui Mining Co., Ltd.), 100 parts of colored particles, 1.0 part of external additive 13 and 2.0 parts of external additive 14 are mixed for 5 minutes, and further 2.0 parts. The external additive 1 was added and mixed for 2 minutes to obtain a toner. The Henschel mixer used A0 as the upper blade and ST as the lower blade, and the peripheral speed at the tip of the lower blade was fixed at 40 m / sec.

The toner had an acid value of 22.4 mgKOH / g, T1 / 2 of 120 ° C., and an average circularity of 0.922.
(Examples 2-7, Comparative Examples 1-9)
A toner was obtained in the same manner as in Example 1 except that the combination of external additives was changed as shown in Table 3.

（評価方法及び評価結果）
上記トナーに対して、下記の各評価を行った。結果を表４に示す。

(Evaluation method and evaluation results)
The following evaluations were performed on the toner. The results are shown in Table 4.

地汚れは、ｉｐｓｉｏ ＣＸ３０００（リコー社製）を用いて、印字率６％の所定のプリントパターンをＮ／Ｎ環境下（２３℃、４５％ＲＨ）で２０００枚連続印字して、評価した。なお、画像上に地汚れが発生しないものを○、画像上に地汚れが若干発生しているものの、実用上問題ないものを△、画像上に地汚れが発生しており、実用上問題があるものを×として、判定した。

The background stain was evaluated by using an ipsio CX3000 (manufactured by Ricoh Co., Ltd.) and continuously printing 2000 sheets of a predetermined print pattern with a printing rate of 6% in an N / N environment (23 ° C., 45% RH). It should be noted that ◯ indicates that no background stain occurs on the image, △ indicates that there is slight background contamination on the image, but Δ indicates that there is no practical problem, and background contamination occurs on the image. Some were judged as x.

For transfer failure, ipsio CX3000 is used to fill each developer with the same toner, and a predetermined print pattern with a print rate of 6% is continuously printed in an N / N environment (23 ° C., 45% RH) for 2000 sheets. And then evaluated. At this time, the general pattern image was output by adjusting the bias so that the total toner adhesion amount on the intermediate transfer member was 1.4 mg / cm ² . It should be noted that the case where no hollows are generated on the image is indicated by ○, the case where some hollows are generated on the image, but there is no practical problem, and the case where many hollows are generated on the image. Judgment was given as x.

  The cleaning performance was determined by visually checking the photoconductor and the intermediate transfer member after 2000 continuous printing of a predetermined print pattern with a printing rate of 6% in an N / N environment (23 ° C., 45% RH) using ipsio CX3000. Evaluation was made by observation. O in which there is no wiping or filming on the photoconductor and intermediate transfer body, and there is no wiping or filming on the photoconductor and / or intermediate transfer body, but there is no practical problem. In the photoconductor and / or the intermediate transfer member, unwiping and filming were observed, and those having problems in practical use were evaluated as x.

The fixing separation property was evaluated as follows. A two-component developer prepared by mixing and stirring 5 parts of toner and 95 parts of a silicone resin coated carrier is put into a modified machine from which the fixing machine of ipsio CX7500 (manufactured by Ricoh) is removed, and transfer paper type 6200Y paper (Ricoh) Was adjusted so that 1.1 mg / cm ² of toner was developed with a solid image having a vertical margin of 3 mm, and an unfixed image was formed. Take out only the fixing part of the ipsio CX2500 (manufactured by Ricoh) and set the linear velocity of the fixing belt to 125 mm / sec using a fixing test device modified so that the temperature and linear velocity of the fixing belt become the desired values. The fixing separation property was evaluated by fixing the transfer paper from the tip margin of 3 mm in increments of 10 ° C. in the range of 140 to 190 ° C., and obtaining a separable / non-offset temperature range. Here, the separable / non-offset temperature range means a fixing temperature range in which the paper is satisfactorily separated from the heating roller and no offset phenomenon occurs. In addition, it was determined that the separable / non-offset temperature range was 50 ° C. or higher, ◯, 30 ° C. or higher and lower than 50 ° C.

The fixing strength was evaluated as follows. A two-component developer prepared by mixing and stirring 5 parts of toner and 95 parts of a silicone resin coated carrier is placed in a modified machine with the ipsio CX7500 fixing machine removed, and the leading edge margin in the vertical direction is placed on the transfer paper type 6200Y paper. An adjustment was made so that 1.1 ± 0.1 mg / cm ² of toner was developed with a solid image having 100 mm, and an unfixed image was formed. Take out only the fixing part of the ipsio CX2500 and set the fixing belt linear velocity to 125 mm / sec and the temperature to 140 ° C. using a fixing test device modified so that the fixing belt temperature and linear velocity become the desired values. The transfer paper was fixed. Further, using a drawing tester AD-401 (manufactured by Ueshima Seisakusho Co., Ltd.), a sapphire needle 125 μR was caused to run on the fixed image in a contact state under the conditions of a needle rotation diameter of 8 mm and a load of 1 g. The fixing strength was evaluated by visually observing the occurrence of scratches (running traces) on the running surface of the part. In addition, it is ◯ when the running trace is hardly recognized, and the running trace is slightly recognized when observed from directly above the image, but △ when there is no practical problem, and the running trace is clearly observed when observed from directly above the image. It was judged as x which was recognized and has a problem in practical use.

It is a figure explaining the method of calculating | requiring an acid point and a base point.

Claims (8)

In a toner having colored particles containing a binder resin, a colorant and a release agent , first inorganic particles, and second inorganic particles ,
The release agent has a melting point of 70 ° C. or higher and 90 ° C. or lower,
Colored particles, the content of the release agent is 10 wt% or less than 3 wt%, volume average particle size is at 4μm or 9μm or less,
The ratio of the total weight of the first inorganic particles and the second inorganic particles to the weight of the colored particles is 0.04 or more and 0.05 or less,
The first inorganic particles are surface-treated with silicone oil and / or hexamethyldisilazane, the base point is substantially 0 μmol / g, and the specific surface area is 80 m ² / g or more and 300 m ² / g or less. Yes,
The second inorganic particles are surface-treated with aminosilane and silicone oil and / or hexamethyldisilazane, have a base point of 50 μmol / g or more and 300 μmol / g or less, and have an acid point per unit specific surface area. 20 [mu] mol / ^m is ² or more, the base point per unit specific surface area of 2.5 .mu.mol / ^{m 2} or more, the toner, wherein the specific surface area is less than ^{15 m} 2 / g or more ^35m 2 / g. The first inorganic particles have an average primary particle size of 10 nm or more and 20 nm or less,
The toner according to claim 1, wherein the second inorganic particles have an average primary particle diameter of 55 nm or more and 80 nm or less. The binder resin, toner according to claim 1 or 2, characterized in that it contains a port Riesuteru resin. The releasing agent, the toner according to any one of claims 1 to 3, characterized in that it contains a carbonaceous hydrocarbon wax.   A step of mixing colored particles containing a binder resin, a colorant and a release agent, and first inorganic particles;
  A step of mixing the mixed colored particles and the first inorganic particles with the second inorganic particles;
  The release agent has a melting point of 70 ° C. or higher and 90 ° C. or lower,
  The colored particles have a content of the release agent of 3% by weight or more and 10% by weight or less, and a volume average particle size of 4 μm or more and 9 μm or less.
  The ratio of the total weight of the first inorganic particles and the second inorganic particles to the weight of the colored particles is 0.04 or more and 0.05 or less,
  The first inorganic particles are surface-treated with silicone oil and / or hexamethyldisilazane, the base point is substantially 0 μmol / g, and the specific surface area is 80 m. ² / G or more 300m ² / G or less,
  The second inorganic particles are surface-treated with aminosilane and silicone oil and / or hexamethyldisilazane, have a base point of 50 μmol / g or more and 300 μmol / g or less, and have an acid point per unit specific surface area. 20 μmol / m ² The basic point per unit specific surface area is 2.5 μmol / m. ² The specific surface area is 15 m. ² / G or more 35m ² / G or less, a method for producing toner. Developing agent characterized by containing the toner according to any one of claims 1 to 4. Using a developing agent according to claim 6, by developing the electrostatic image formed on the electrostatic image bearing member, forming a toner image,
Transferring the toner image to a transfer medium ;
An image forming method comprising a step of heat-fixing a toner image transferred to the transfer medium using a roller having a heating device. Using a developing agent according to claim 6, by developing the electrostatic image formed on the electrostatic image bearing member, forming a toner image,
Transferring the toner image to a transfer medium ;
An image forming method comprising a step of heat-fixing a toner image transferred to the transfer medium using an oilless fixing device.

Images