JPH09319155A - Electrostatic latent image developing carrier, its production, electrostatic latent image developer and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain good electrification charge property even for long-term continuous use without changes in the charge due to environmental changes by forming a resin coating layer comprising three kinds of resins consisting of a hardening resin containing a triazine ring, a crosslinking agent which crosslinks with the hardening resin, and a fluorine-contg. org. resin which does nor crosslink. SOLUTION: At least three kinds of resins, winch are a hardening resin containing a triazine ring, a resin which crosslinks with the hardening resin, and a fluororesin which does not crosslink with the hardening resin are used as a coating resin. The resin coating film has such a density gradient that a larger amt. of the fluoroesin is present on the surface of the resin coating film while the amt. of the crosslinkled hardening resin containing the triazing ring increases toward the surface of the core material. As for the hardening resin containing the triazine ring, melamine, guanamine, cyanuric chloride, ammeline can be used, and especially melamine and guanamine are preferably, As for the crosslinking agent, a single polymer or copolymer of monomers containing hydroxyl groups can be used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrier for developing an electrostatic latent image used for developing an electrostatic latent image in an electrophotographic method or an electrostatic recording method, a method for producing the carrier, and a carrier containing the carrier. The present invention relates to an electrostatic latent image developer and an image forming method using the developer.

[0002]

2. Description of the Related Art Conventionally, in electrophotography, an electrostatic latent image is formed on a photosensitive member or an electrostatic recording member by using various means,
A method of developing an electrostatic latent image by attaching electroconductive fine particles called toner to the electrostatic latent image is generally used. During this development, carrier particles called carriers are mixed with toner particles and frictionally charged with each other to give an appropriate amount of positive or negative electric charge to the toner. Carriers are roughly classified into coated carriers having a coating layer on the surface and non-coated carriers not having a coating layer. However, considering the life of the developer, the coated carrier is superior to various types. The coating film carrier has been developed and put into practical use.

Although there are various characteristics required of the coating film carrier, it is required to impart an appropriate amount of electric charge to the toner (amount of electric charge and electric charge distribution) and maintain its appropriate charging property for a long period of time. For that, the impact resistance of the carrier,
Anti-friction, and against environmental changes such as humidity and temperature,
It is important not to change the chargeability of the toner, and various coated carriers have been proposed.

For example, melamine resin and epoxy resin,
A carrier having a relatively hard coating formed by coating a resin which is a combination of a resin selected from an acrylic resin and an alkyd resin on the surface of a carrier core material and curing the same has been proposed (see JP-B-58-9946). . Further, a carrier having a coating film having excellent durability obtained by crosslinking a melamine resin and an acrylic resin has been proposed (JP-A-5-2162).
No. 81). However, these carriers have problems such as spread of charge distribution due to melamine resin, charge change due to environmental changes, and adhesion of toner and external additives to the carrier.

On the other hand, in order to prevent the toner and external additives from adhering to the carrier, the surface of the carrier core material is coated with a melamine resin and a fluorine-containing alkyl which crosslinks with the melamine resin to effect crosslinking, thereby preventing the above-mentioned contamination. A carrier having is proposed (see Japanese Patent Publication No. 5-52493). However, since the melamine structure due to the cross-linking is present in a considerable amount on the surface as well as the inside of the carrier, the charge distribution cannot be prevented and the change in charge due to environmental changes cannot be prevented, and the above problems have not been solved. .

[0006]

SUMMARY OF THE INVENTION Therefore, the present invention solves the above-mentioned problems, does not cause a change in charge due to environmental changes, has a narrow charge distribution, and can maintain a good chargeability even during long-term continuous use. An object of the present invention is to provide a carrier for developing an electrostatic latent image capable of forming a good copy image, a manufacturing method thereof, an electrostatic latent image developer, and an image forming method.

[0007]

Means for Solving the Problems In order to solve the above-mentioned problems, the inventors of the present invention have made earnest researches and studies on a carrier for developing an electrostatic latent image, and as a result, by adopting the following constitution, The problem was solved successfully.

(1) In a carrier for electrostatic latent image development in which a core material is coated with a resin, a curable resin (raw material) containing a triazine ring, a crosslinking agent for crosslinking the curable resin, and
A carrier for developing an electrostatic latent image, which has a resin coating layer made of at least three types of fluorine-containing resins that are not crosslinked. (2) The resin coating layer has a large amount of fluorine-containing resin on the surface,
The electrostatic latent image developing carrier as described in (1) above, which has a concentration gradient in which a large amount of crosslinked curable resin containing a triazine ring is present toward the surface of the core material.

(3) The carrier for developing an electrostatic latent image according to (1) or (2) above, wherein a resin containing no hydroxyl group is used as the fluorine-containing resin. (4) The electrostatic latent image developing carrier as described in any one of (1) to (3) above, wherein the three types of coating resins have compatibility with each other. (5) The electrostatic latent image developing carrier as described in any one of (1) to (4) above, wherein the three kinds of coating resins contain the same kinds of monomer units.

(6) The electrostatic latent image developing carrier as described in any one of (1) to (5) above, wherein the coating resin contains conductive powder. (7) The carrier for developing an electrostatic latent image according to any one of (1) to (6) above, wherein the resin coating layer has a thickness of 0.1 to 10 μm. (8) The carrier for developing an electrostatic latent image according to any one of (1) to (7) above, wherein the carrier has an average particle size of 30 to 150 μm.

(9) In the method for producing a carrier for developing an electrostatic latent image in which a core material is coated with a resin, a curable resin containing a triazine ring, a cross-linking agent that cross-links the curable resin, and a fluorine-containing non-crosslinkable resin. Production of a carrier for developing an electrostatic latent image, which comprises coating a core material with a coating resin composed of at least three kinds of resins and then heating and curing the mixture at a temperature of 80 to 250 ° C. for 1 to 100 minutes while stirring. Method.

(10) The method for producing a carrier for electrostatic latent image development according to the above (9), wherein compatible resins are used as the three kinds of coating resins. (11) Regarding the curable resin containing the triazine ring, the cross-linking agent, and the non-cross-linking fluorine-containing resin, the weight ratio of the curable resin and the cross-linking agent is in the range of 1: 9 to 9: 1, and The electrostatic latent image according to the above (9) or (10), wherein the sum of the curable resin and the cross-linking agent and the fluorine-containing resin are mixed in a weight ratio of 1: 9 to 9: 1. Method of manufacturing carrier for development. (12) The method for producing a carrier for developing an electrostatic latent image according to any one of (9) to (11) above, wherein an acid catalyst is added to the three types of coating resins.

(13) An electrostatic latent image developer comprising the carrier and the toner according to any one of (1) to (8) above. (14) The electrostatic latent image developer according to the above (13), wherein the binder resin of the toner contains at least linear polyester. (15) As a binder resin for the toner, a softening point of 90 to 150
℃, glass transition point 50 ~ 70 ℃, number average molecular weight 2000
~ 6000, weight average molecular weight 8000 to 150,000,
The electrostatic latent image developer according to (13) or (14) above, which uses a resin having an acid value of 5 to 30 and a hydroxyl value of 5 to 40. (16) The electrostatic latent image developer according to any one of (13) to (15) above, wherein the toner has an average particle size in the range of 3 to 9 μm.

(17) Using the developer layer on the developer carrier,
In the method of developing an electrostatic latent image on an electrostatic latent image carrier to form an image, it is preferable to use the electrostatic latent image developer according to any one of (13) to (16) above. A characteristic image forming method.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have found that the triazine ring structure is excellent in charge-imparting ability and charge-holding ability, but has a drawback that the charge distribution is wide and the change in chargeability due to environmental changes is large. Resins are excellent in coating strength, but when they are cured independently, they have problems with brittleness and adhesion to the substrate. Fluorine-containing resins have excellent stain resistance, but there are problems with charging ability and coating strength. Focusing attention, a curable resin containing a triazine ring, a resin that can be crosslinked with the curable resin, and a fluorine-containing resin that does not crosslink with the curable resin are used as coating resins, and the surface of the resin coating layer is used. There is a large concentration of fluorine-containing resin and a large amount of cross-linked curable resin containing triazine rings toward the surface of the core material, so there is no change in charge due to environmental changes, the charge distribution is narrow, and It was it possible to provide a resin-coated carrier for electrostatic latent image development which can maintain a good charging capability for successive use.

Examples of the curable resin containing a triazine ring used in the present invention include curable resins containing a triazine ring such as melamine, guanamine, cyanuric chloride, and ammeline. Among them, melamine and guanamine are preferable.

As the crosslinking agent for crosslinking the curable resin containing a triazine ring, a homopolymer or a copolymer obtained by polymerizing a monomer containing a hydroxyl group can be used. The hydroxyl group-containing monomer is preferably hydroxyalkyl acrylate such as hydroxyethyl acrylate or hydroxybutyl acrylate; hydroxyalkyl methacrylate such as hydroxyethyl methacrylate or hydroxybutyl methacrylate. As the copolymerizable monomer, styrenes such as styrene and chlorostyrene; monoolefins such as ethylene, propylene, butylene and isoprene; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; Methyl acrylate, ethyl acrylate, butyl acrylate,
Dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate,
Α-Methylene aliphatic monocarboxylic acid esters such as butyl methacrylate and dodecyl methacrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl butyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone Kind of things can be mentioned.

As the fluorine-containing resin which does not crosslink with the curable resin containing a triazine ring, a fluorine-containing resin containing no hydroxyl group can be used. For example, a copolymer of one or more monomers selected from polytetrafluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, polychlorotrifluoroethylene and vinylidene fluoride and a non-fluorinated monomer, fluorinated Fluoroterpolymers such as copolymers of two or more fluorinated monomers and non-fluorinated monomers such as vinylidene and vinyl fluoride, tetrafluoroethylene and vinylidene fluoride, and the like. it can.

The carrier for developing an electrostatic latent image of the present invention comprises a cross-linking agent that cross-links the curable resin and a monomer unit of the same kind as the non-cross-linking fluorine-containing resin in order to increase the compatibility of the curable resin and the non-cured resin. Is preferred. Specific examples of the monomer include styrenes such as styrene and chlorostyrene; monoolefins such as ethylene, propylene, butylene and isoprene; vinyl esters such as vinyl acetate, vinyl propionate and vinyl benzoate; methyl acrylate. , Α-methylene aliphatic monocarboxylic acid esters such as ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate; vinyl; Examples thereof include vinyl ethers such as methyl ether, vinyl ethyl ether and vinyl butyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone.

The coat structure of the carrier of the present invention has a concentration gradient in which a large amount of a fluorine-containing resin is present on the surface and a curable resin containing a triazine ring and a resin crosslinked with the triazine ring are present in the direction of the core material. It is preferable. When the compatibility is good, the concentration gradient becomes gentle as compared with the poor compatibility, and the charging characteristics and the coating characteristics can be further improved.

In the method for producing a carrier for developing an electrostatic latent image according to the present invention, the core material is coated with the above coating resin, and then 80 to 25.
It is characterized by heating and stirring at 0 ° C, preferably 100 to 200 ° C. Heating / stirring time is 1 to 100 minutes,
It is preferable to carry out the treatment for about 10 to 60 minutes to obtain a carrier having excellent coating strength. Heating and stirring at 250 ° C. for more than 100 minutes is not preferable because the carrier surface becomes rough and the charging characteristics deteriorate. Further, heating and stirring at a temperature of 80 ° C. or lower for 1 minute is not preferable because the curing is insufficient and the film strength becomes weak.

In the above-mentioned manufacturing method, it is possible to use a small amount of an acid catalyst in order to cure at a low temperature in a short time. Examples of the acid catalyst include sulfonic acid compounds such as sodium dodecylbenzene sulfonate, phthalic anhydride, maleic anhydride, hydrochloric acid and the like. The amount of the acid catalyst used is preferably in the range of 0.01 to 5% by weight.

Further, in order to reduce the electric resistance of the carrier, it is possible to include conductive powder in the coating resin. Examples of the conductive powder include carbon, magnetite, ferrite, silica, titania and the like.

As a method of forming the coating layer on the surface of the carrier core material, for example, powder of carrier core material (including core material of coated carrier and dispersed powder of dispersion type carrier)
Is immersed in a resin solution for forming a coating layer, a spray method in which the resin solution for forming a coating layer is sprayed on the surface of the carrier core material, and a coating layer is formed while the carrier core material is suspended in fluidized air. A fluidized bed method of spraying a resin solution, a kneader coater method of mixing a carrier core material and a resin solution for forming a coating layer in a kneader coater, and removing the solvent can be mentioned. Further, as a device for curing the coating layer,
Fluidized bed equipment and kneader coater equipment are suitable.

As the carrier core material used in the present invention,
Examples thereof include magnetic metals such as iron, steel, nickel, and cobalt, magnetic oxides such as ferrite and magnetite, and glass beads. For use in the magnetic brush method, magnetic carriers are preferable. The average particle size of the carrier core material is generally 10 to 500 μm, preferably 30 to 100 μm.

The solvent used for the resin solution for forming the coating layer is
There is no particular limitation as long as it can dissolve the coating resin, and for example, aromatic hydrocarbons such as toluene and xylene, ketones such as acetone and methyl ethyl ketone, and ethers such as tetrahydrofuran and dioxane are used. be able to. The average film thickness of this coating layer is
A range of 0.1 to 10 μm, preferably 0.2 to 3 μm is suitable.

The electrostatic latent image developing carrier of the present invention has a large amount of non-curable fluorine-containing resin on its surface, and a large amount of a curable resin containing a triazine ring and a resin crosslinked with the triazine ring in the direction of the core material. Has a concentration gradient to Therefore, the fluorine-containing resin has surface characteristics of less contamination, which is an advantage, and it is possible to improve charge change and spread of charge distribution due to environmental change, which is a drawback of the triazine ring. Further, the cross-linking resin improves the adhesion to the core material, improves the strength of the coating resin, and the triazine ring present inside the coating layer makes it possible to provide a carrier having a high charge amount. As a result, it is possible to obtain a carrier having a long life, which is less contaminated due to adhesion of toner or external additives, has no film deterioration such as peeling or chipping, and has excellent charge imparting ability and charge retaining ability. .

The toner used in the carrier of the present invention is
It contains at least a colorant and a binder resin. As the colorant, carbon black, nigrosine, aniline blue, calcoil blue, chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow,
Methylene blue chloride, phthalocyanine blue, malachite green oxalate, lamp black, rose bengal, C.I. I. Pigment Red 48: 1,
C. I. Pigment Red 122, C.I. I. Pigment Red 57: 1, C.I. I. Pigment Yellow 9
7, C.I. I. Pigment Yellow 12, C.I. I. Pigment Blue 15: 1, C.I. I. Pigment Blue 15: 3 and the like can be exemplified.

As the binder resin, styrenes such as styrene and chlorostyrene; monoolefins such as ethylene, propylene, butylene and isoprene; vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate and vinyl acetate; Α-methylene aliphatic monocarboxylic acid esters such as methyl acrylate, ethyl acrylate, butyl acrylate, dodecyl acrylate, octyl acrylate, phenyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, dodecyl methacrylate, etc. Examples: vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl butyl ether; homopolymers or copolymers such as vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and vinyl isopropenyl ketone In particular, typical binder resins include polystyrene, styrene / alkyl acrylate copolymer, styrene / alkyl methacrylate copolymer, styrene / acrylonitrile copolymer, styrene / butadiene copolymer, styrene / styrene. Examples thereof include maleic anhydride copolymer, polyethylene and polypropylene. Further, polyester, polyurethane, epoxy resin, silicone resin, polyamide, modified rosin, paraffin and waxes can be mentioned. Among these,
Polyester is particularly effective. For example, a linear polyester resin composed of a polycondensate containing bisphenol A and a polyvalent aromatic carboxylic acid as main monomer components can be preferably used.

Further, the softening point is 90 to 150 ° C., the glass transition point is 50 to 70 ° C., the number average molecular weight is 2000 to 6000, the weight average molecular weight is 8000 to 150,000, and the acid value is 5 to 30.
Resins having a hydroxyl value of 5 to 40 can be particularly preferably used. These toner particles may optionally contain known additives such as a charge control agent and a fixing aid.

[0031]

【Example】

[Example 1] Ferrite particles (average particle size = 50 µm) 100 parts by weight Toluene 14 parts by weight Butylated melamine (formaldehyde, butanol, toluene containing solution 60% solids) 0.3 parts by weight Perfluorooctylethylmethacrylate / methyl Methacrylate copolymer (copolymerization ratio 20/80) 0.6 parts by weight Styrene / methyl methacrylate / hydroxyethyl methacrylate copolymer (copolymerization ratio 40/40/20) 0.4 parts by weight Put it in the air type kneader and reduce the pressure to 1
The mixture was stirred at 00 ° C for 30 minutes to distill off toluene to form a coating layer. The obtained coated carrier is kneader under normal pressure,
The carrier of Example 1 was obtained by stirring at 200 ° C. for 30 minutes.

Example 2 Ferrite particles (average particle size = 50 μm) 100 parts by weight Toluene 14 parts by weight Guanamine (formaldehyde, butanol, toluene-containing solution: 60% solid content) 0.3 parts by weight Perfluorooctylethylmethacrylate Methyl methacrylate copolymer (copolymerization ratio 20/80) 0.6 parts by weight Styrene / methyl methacrylate / hydroxyethyl methacrylate copolymer (copolymerization ratio 40/40/20) 0.4 parts by weight The above components are vacuumed. Place in a degassing type kneader to reduce the pressure, and temperature 1
The mixture was stirred at 00 ° C for 30 minutes to distill off toluene to form a coating layer. The obtained coated carrier is kneader under normal pressure,
The carrier of Example 2 was obtained by stirring at 200 ° C. for 30 minutes.

[Example 3] Ferrite particles (average particle size = 50 µm) 100 parts by weight Toluene 14 parts by weight Butylated melamine (formaldehyde, butanol, toluene solution containing 60% of solid content) 0.3 parts by weight Perfluorooctyl Ethyl methacrylate / methyl methacrylate copolymer (copolymerization ratio 20/80) 0.6 parts by weight Vinyl acetate / methyl methacrylate / hydroxyethyl methacrylate copolymer (copolymerization ratio 40/40/20) 0.4 parts by weight Sodium dodecylbenzene sulfonate 0.003 parts by weight The above components are put into a vacuum degassing kneader to reduce the pressure, and the temperature is set to 1
The mixture was stirred at 00 ° C for 30 minutes to distill off toluene to form a coating layer. The obtained coated carrier is kneader under normal pressure,
The carrier of Example 3 was obtained by stirring at 150 ° C. for 20 minutes.

Comparative Example 1 Ferrite particles (average particle size = 50 μm) 100 parts by weight Toluene 14 parts by weight Butylated melamine (formaldehyde, butanol, toluene solution containing 60% solid content) 0.6 parts by weight Polymethylmeta Acrylate 1 part by weight The above components were put in a vacuum degassing type kneader to reduce the pressure, and the temperature was adjusted to 1
The mixture was stirred at 00 ° C for 30 minutes to distill off toluene to form a coating layer. The obtained coated carrier is kneader under normal pressure,
The carrier of Comparative Example 1 was obtained by stirring at 200 ° C. for 30 minutes.

Comparative Example 2 Ferrite particles (average particle size = 50 μm) 100 parts by weight Toluene 14 parts by weight Butylated melamine (formaldehyde, butanol, toluene solution containing 60% solid content) 0.6 parts by weight Styrene / methyl Methacrylate / hydroxyethyl methacrylate copolymer (copolymerization ratio 40/40/20) 1 part by weight The above components were put in a vacuum degassing type kneader to reduce the pressure, and the temperature was adjusted to 1
The mixture was stirred at 00 ° C for 30 minutes to distill off toluene to form a coating layer. The obtained coated carrier is kneader under normal pressure,
The carrier of Comparative Example 2 was obtained by stirring at 200 ° C. for 30 minutes.

Comparative Example 3 Ferrite particles (average particle size = 50 μm) 100 parts by weight Toluene 14 parts by weight Butylated melamine (formaldehyde, butanol, toluene solution containing 60% solid content) 0.6 parts by weight Polytetrafluoroethylene / Methyl methacrylate / hydroxyethyl methacrylate copolymer (copolymerization ratio 20/60/20) 1 part by weight The above components are put in a vacuum degassing kneader to reduce the pressure, and the temperature is set to 1
The mixture was stirred at 00 ° C for 30 minutes to distill off toluene to form a coating layer. The obtained coated carrier is kneader under normal pressure,
The carrier of Comparative Example 3 was obtained by stirring at 200 ° C. for 30 minutes.

(Production of magenta toner) 100 parts by weight of linear polyester resin (linear polyester obtained from terephthalic acid / bisphenol A and ethylene oxide adduct / cyclohexane dimethanol; Tg = 62 ° C., Mn = 4,000, Mw = 35,000, acid value = 12, hydroxide value = 25, softening point Ts = 120 ° C.) Magenta pigment (CI Pigment Red 57) 3 parts by weight The above mixture was kneaded with an extruder and jet-milled. After crushing, the particles were dispersed by a wind classifier to obtain magenta toner particles having d ₅₀ = 8 μm. R972 (manufactured by Nippon Aerosil Co., Ltd., silica) was added to the magenta toner particles in an amount of 0.4 parts by weight using a Henschel mixer to obtain a magenta toner having an average particle diameter of 8 μm.

(Preparation of Developer) 100 parts by weight of each of the carriers of Examples 1 to 3 and Comparative Examples 1 to 3 were mixed with 6 parts by weight of the above magenta toner to prepare 6 kinds of developers.

(Evaluation) Using these developers 1 to 6, an electrophotographic copying machine (A-Col, manufactured by Fuji Xerox Co., Ltd.) was used.
or 630), and a copy test was conducted. Environment is high temperature high humidity (30 ℃, 80%) and low temperature low humidity (10 ℃, 15%)
It was conducted under each of the two environments. The results are shown in Table 1. In Table 1, the background stain is the result of visual observation of the copy, and the solid density is X-Rit manufactured by X-Rite.
It was measured by e404.

When a copying test was conducted on 100,000 sheets, the developers 1 to 3 according to the examples were free from fluctuations in image density and stains on the background, and stable images were obtained. However, in the developers 4 to 6 according to the comparative examples, the charge amount gradually decreases in a high temperature and high humidity environment, the charge distribution becomes wider, and the background stain is observed.
In-flight toner stains were also seen.

[0041]

[Table 1]

[0042]

[Table 2]

(Production of Black Toner) Linear Polyester Resin 100 parts by weight (linear polyester obtained from terephthalic acid / bisphenol A and ethylene oxide adduct / cyclohexane dimethanol; Tg = 62 ° C., Mn = 4,000, Mw = 35,000, acid value = 12, hydroxyl value = 25, softening point Ts = 120 ° C.) Carbon black (Cabot Co., Mogul L) 6 parts by weight The above mixture was kneaded with an extruder to obtain a volume pulverization system. After crushing with a crusher, fine particles and coarse particles were classified with an air classifier to obtain black toner particles with d ₅₀ = 9 μm. 0.49 of R972 (manufactured by Nippon Aerosil Co., Ltd.) is added to the black toner particles.
Weight part, added with a Henschel mixer, average particle size 9 μm
Black toner was obtained.

(Preparation of Developer) 100 parts by weight of each of the carriers of Examples 1 to 3 and Comparative Examples 1 to 3 were mixed with 6 parts by weight of the black toner to prepare 6 kinds of developers.

(Evaluation) Using these developers 7 to 12, an electrophotographic copying machine (A-Col, manufactured by Fuji Xerox Co., Ltd.) was used.
or 630), and a copy test was conducted. Environment is high temperature high humidity (30 ℃, 80%) and low temperature low humidity (10 ℃, 15%)
It was conducted under each of the two environments. The results are shown in Table 2. In Table 2, the background stain is the result of visual observation of the copy, and the solid density is X-Rit manufactured by X-Rite.
It was measured by e 404.

When a copying test was performed on 100,000 sheets, the developers 7 to 9 according to the examples were free from fluctuations in image density and background stains, and stable images were obtained. However, in the developers 10 to 12 according to the comparative examples, the charge amount gradually decreased in a high temperature and high humidity environment, the distribution of charge was widened, and the background stain and the in-machine toner stain were also seen.

[0047]

[Table 3]

[0048]

[Table 4]

[0049]

EFFECTS OF THE INVENTION The present invention, by adopting the above-mentioned constitution, is for electrostatic latent image development which does not cause a change in charge due to environmental changes, has a narrow charge distribution, and maintains good charge performance for continuous use for a long time. A carrier or developer can be provided so that a good quality copy image can be maintained.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical indication location G03G 9/10 361 (72) Inventor Noriyuki Mizutani 1600 Takematsu, Minamiashigara-shi, Kanagawa Fuji Xerox Co., Ltd.

Claims (15)

[Claims] 1. A carrier for electrostatic latent image development comprising a core material coated with a resin, comprising a curable resin containing a triazine ring, a cross-linking agent that cross-links the curable resin, and a fluorine-containing resin that does not cross-link. An electrostatic latent image developing carrier having a resin coating layer made of at least three kinds of resins. 2. The resin coating layer has a concentration gradient in which a large amount of fluorine-containing resin is present on the surface and a large amount of crosslinked curable resin containing a triazine ring is present toward the surface of the core material. The electrostatic latent image developing carrier described. 3. The electrostatic latent image developing carrier according to claim 1, wherein a resin containing no hydroxyl group is used as the fluorine-containing resin. 4. The electrostatic latent image developing carrier according to claim 1, wherein the three kinds of coating resins have compatibility with each other. 5. The electrostatic latent image developing carrier according to claim 1, wherein the three types of coating resins contain the same type of monomer units. 6. The electrostatic latent image developing carrier according to claim 1, wherein the coating resin contains a conductive powder. 7. The resin coating layer has a thickness of 0.1 to 10 μm.
7. The electrostatic latent image developing carrier according to claim 1, wherein the carrier is in the range of m. 8. The average particle size of the carrier is 30 to 15
The carrier for developing an electrostatic latent image according to claim 1, wherein the carrier is in the range of 0 μm. 9. A method of manufacturing a carrier for developing an electrostatic latent image, comprising coating a core material with a resin, a curable resin containing a triazine ring, a cross-linking agent that cross-links the curable resin, and a fluorine-containing resin that does not cross-link. A method for producing a carrier for developing an electrostatic latent image, which comprises coating a core material with a coating resin composed of at least three kinds of resins, and then heat curing the mixture at a temperature of 80 to 250 ° C. for 1 to 100 minutes with stirring. . 10. The method of manufacturing a carrier for developing an electrostatic latent image according to claim 9, wherein compatible resins are used as the three kinds of coating resins. 11. The method for producing a carrier for developing an electrostatic latent image according to claim 9, wherein an acid catalyst is added to the three kinds of coating resins. 12. An electrostatic latent image developer comprising the carrier according to any one of claims 1 to 8 and a toner. 13. The binder resin of the toner contains at least linear polyester.
The electrostatic latent image developer as described in the above. 14. The average particle diameter of the toner is 3 to 9 μm.
14. The electrostatic latent image developer according to claim 12 or 13, characterized in that 15. Using a developer layer on a developer carrier,
A method for developing an electrostatic latent image on an electrostatic latent image carrier to form an image, characterized in that the electrostatic latent image developer according to any one of claims 12 to 14 is used. Image forming method.