JP2000075532A - Production of electrophotographic photoreceptor, electrophotographic photoreceptor, image forming method using the same and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic photoreceptor particularly free from the dissolution of a conductive layer of the lower layer at the time of lamination, having excellent adhesion of a base body to the conductive layer, excellent potential stability with time and excellent repeating use property and free from the occurrence of image defect in the electrophotographic photoreceptor formed by applying an organic photosensitive layer on a resin base body and the producing method, an image forming method using the same and an image forming device. SOLUTION: In the producing method of the electrophotographic photoreceptor by successively laminating the conductive layer and the organic photosensitive layer on the resin base body, a coating liquid, in which a conductive fine particle and a binder resin are incorporated and the binder resin in a (metha) acrylic resin and which exhibits 3.0-90 wt.% methyl ethyl ketone dissolving ratio in the heat treatment of 80 deg.C.1 hr, is used for the conductive layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electrophotographic photosensitive member, an electrophotographic photosensitive member, and an image forming method and an image forming apparatus using the same.

[0002]

2. Description of the Related Art In an image forming apparatus for forming an image by an electrophotographic method, a rotating drum or a belt-shaped electrophotographic photosensitive member (electrostatic image forming member) is charged, image-exposed, and developed to form an electrostatic image. A toner image is formed on a charge image forming body, and the toner image is transferred to a transfer material and fixed. In order to fulfill its function, the electrostatic image forming body is arranged around a charger, an exposure device, a developing device, a transfer device, a static eliminator, a cleaning device, etc.
It is necessary to move at a predetermined speed at a predetermined timing without changing the pressed state.

In order to be used repeatedly, once the role in one cycle of the image forming process is completed, it is necessary to return to the original position in the original state in preparation for the next image forming cycle. In order to smooth this series of movements and efficiently use expensive members such as a photosensitive drum, in a practically used apparatus, a photosensitive layer is formed on the peripheral surface of an almost cylindrical substrate as an electrostatic image forming body. The provided photosensitive drum is used.

At present, as the electrophotographic photoreceptor, an organic photoreceptor of a multilayer type is used very often. In this case, as a method of applying a photosensitive liquid on the outer surface of a drum formed in a cylindrical shape to manufacture an electrophotographic photoreceptor, a circular amount-regulated coating method such as a slide hopper method, a spray coating method,
Dip coating, blade coating, roll coating and the like are known.

As the material of the cylindrical substrate, a metal material such as aluminum is often used. However, there is a limit in productivity and cost reduction in forming a cylindrical substrate by machining using a metal material.

In this respect, resin is considered to be a preferable material because of its light weight and low cost, but it is not easy to produce a high-precision resin at a high yield. Also, unlike aluminum substrates, etc., the coating of the organic photoreceptor coating liquid is poor,
In some cases, the coating cannot be performed uniformly, or in some cases, cannot be performed at all. In addition, because resin is not conductive,
It is necessary to apply a conductive layer to the surface of the substrate, but this conductive layer is not uniform due to the solvent of the charge generation layer and the charge transport layer applied on the upper layer, and the adhesion to the substrate is impaired. It has been found that deterioration of the performance of the photoreceptor based on these is also a serious problem.

As will be described in detail later, for an image forming apparatus configured to perform image exposure from inside the electrostatic image forming body, the cylindrical substrate of the electrostatic image forming body is exposed to light from inside. And the base material cannot be made of metal. Therefore, there is a problem that the image forming method of exposing an image from the inside is not practically practical even though the apparatus configuration is excellent.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrophotographic photoreceptor having an organic photosensitive layer coated on a resin substrate, in particular, without dissolving the lower conductive layer at the time of layering. Electrophotographic photoreceptor having good adhesion performance of conductive layer, good potential stability over time, good repetitive use characteristics, and free from image defects, method of manufacturing the same, image forming method using the same, and image formation It is to provide a device.

[0009]

The object of the present invention is achieved by adopting the following constitution.

[1] In a method of manufacturing an electrophotographic photoreceptor in which a conductive layer and an organic photosensitive layer are sequentially coated on a resin substrate, the coating liquid for the conductive layer contains conductive fine particles and a binder resin. A method for producing an electrophotographic photoreceptor, comprising a cross-linkable (meth) acrylic acid resin, wherein the coating liquid has a methyl ethyl ketone dissolution rate of 3.0 to 90% by weight after heat treatment at 80 ° C. for 1 hour.

[2] In an electrophotographic photosensitive member in which a conductive layer and an organic photosensitive layer are sequentially coated on a resin substrate, the coating liquid for the conductive layer contains conductive fine particles and a binder resin, and the resin has a self-crosslinking property. An electrophotographic photoreceptor, which is a (meth) acrylic acid resin, wherein the coating liquid has a methyl ethyl ketone dissolution rate of 3.0 to 90% by weight after heat treatment at 80 ° C. for 1 hour.

[3] The electrophotographic photosensitive member according to [2], wherein the resin substrate is made of a vinyl polymer resin.

[4] The electrophotographic photosensitive member according to [2] or [3], wherein the resin substrate is made of a crosslinkable polymer resin.

[5] The resin substrate is produced by a centrifugal polymerization method [2], [3] or [4].
The electrophotographic photosensitive member according to the above.

[6] The electrophotographic photosensitive member according to any one of [2] to [5], which is a photosensitive member for internal exposure.

[7] The surface of the electrophotographic photoreceptor is uniformly charged, and image exposure and color development are repeated to form a multicolor superimposed image, which is subjected to batch transfer, separation, fixing, and photoreceptor cleaning steps. An image forming apparatus for forming an image, wherein the electrophotographic photosensitive member according to [2] is used, the image is exposed through a translucent substrate, and the image is formed by non-contact development.

[8] A step of uniformly charging the surface of the electrophotographic photosensitive member, an image exposing step, and a color developing step are repeated to form a multicolor superimposed image, a batch transferring step, a separating step, a fixing step, and a photosensitive step. In the image forming method which goes through each step of the body cleaning, the image is formed by using the electrophotographic photosensitive member according to [2], exposing the image through a light-transmitting substrate, and forming an image by non-contact development. Forming method.

In general, an organic electrophotographic photosensitive member (OPC) is composed of a conductive layer (necessary for an insulating substrate such as a resin substrate) and a charge generating layer (CG) on a substrate.
L), a photosensitive layer such as a charge transport layer (CTL), an intermediate layer such as an undercoat layer, and a protective layer if necessary. Of these,
The conductive layer is applied directly on the resin substrate. The present inventors have conducted intensive studies, and as a result, the conductivity and applicability of the conductive layer,
The present inventors have found that solubility in a solvent has a great effect on the characteristics of the photoreceptor, and have reached the present invention.

In the present invention, the self-crosslinkable resin is a resin having a crosslinkable functional group, or a resin obtained by copolymerizing a monomer having two or more kinds of functional groups. (Crosslinking) to form a stitch structure.

For example, glycidyl and carboxyl, glycidyl and amino, glycidyl and acid anhydride, glycidyl and OH or N-methylol (or N-methylol)
A methylol ether group, the same applies to the following) and a carboxyl group, an N-methylol group and an amino group, an N-methylol group and an acid anhydride, an N-methylol group and an OH group or N-methylol groups, or two or more of the above. And the like. A self-crosslinkable resin can be crosslinked at a relatively low temperature (〜90 ° C.), whereas a reactive crosslinkable resin using a so-called crosslinking agent is crosslinked at a relatively high temperature (〜130 ° C.).
Pot life also has a long advantage. It should be noted that a small amount of a crosslinking agent may be added to the self-crosslinkable resin to take advantage of both the reaction type and the self-crosslinking type.

The conductive layer is made of conductive fine particles such as ITO (indium tin oxide), Sn
It is formed by applying a liquid in which metal oxide fine particles such as O ₂ and alumina are dispersed. Regarding the particle size of the metal oxide particles, the number average primary particle size is preferably 1 to 100 nm in order for the coating film to have sufficient light transmittance and obtain good optical characteristics.

As a method for measuring the dissolution rate of methyl ethyl ketone (MEK), a paint for a conductive layer is applied on a PET base so as to have a dry film thickness of 1.5 μm, dried by heat treatment at 80 ° C. for 1 hour, and then dried at 23 ° C. The base is immersed in the liquid for 1 hour, the weight of the base applied before and after immersion and the weight of the base alone are measured, and the weight is obtained by the following equation.

{(Weight before immersion-weight after immersion) / (weight of base coated before immersion-weight of base only)} × 10
0 The effluent also includes a conductive substance contained in the layer.

According to MEK dissolution rate and test, 90% by weight
If it is larger than the lower layer, the lower layer starts to melt at the time of layering and there is a boundary between the layers, so that the residual potential increases. If the content is less than 3.0% by weight, the crosslinking density is too high, the composition becomes hard and brittle, cracks are generated, and the adhesiveness is reduced, and the durability is deteriorated. The preferred range is 3.0 to 90% by weight, and more preferably 5.0 to 85% by weight.

In order to make the MEK solubility 3.0 to 90% by weight, it is advisable to control the heat treatment temperature and time, including the type and ratio of the crosslinkable monomer and the monomer to be copolymerized.

Commonly used monomers include acrylic acid, methacrylic acid, itaconic acid, acrylamide, methacrylamide, N-methylolacrylamide, glycidyl (meth) acrylate, β-hydroxyethyl (meth) Examples include acrylate, dimethylethyl methacrylate, hydroxypropyl (meth) acrylate, polyethylene glycol dimethacrylate, and iminol methacrylate. At least one of these is used, but usually it is preferable to use two or more of them.

Further, as a vinyl monomer having no functional group copolymerizable therewith, a vinyl monomer commonly used, for example, a styrene monomer, (meth)
There are monomers such as acrylate monomers, vinyl acetate, vinyl chloride, and vinylidene chloride.

With respect to the coating method, a circular amount control type coating method such as a slide hopper method, a spray coating method, a dip coating method,
There are a blade coating method and a roll coating method, and there is no particular limitation, but a dip coating method is most suitable.

Next, the resin substrate for an electrophotographic photosensitive member of the present invention will be described.

The resin substrate in the present invention is prepared by a centrifugal polymerization method,
It is produced by injection molding, extrusion molding or the like.

The production by centrifugal polymerization, which is a typical production method, will be specifically described as shown in FIG. 1, and FIG. 2 shows an example of the production apparatus. In the manufacturing apparatus of FIG.
C1 is a cylindrical mold, and the inner surface forms a good cylindrical surface with high accuracy. C2 is a heating member for heating from outside the mold C1. C3 is a mold holding member that sandwiches the mold C1 from the left and right, so that the liquid inside the mold C1 does not leak in the sandwiched state. C4 is an inlet for injecting the polymerizable liquid material. C5 is a thermometer for measuring the temperature inside the mold C1.
This apparatus has a structure in which the axis of the mold C1 is adjusted to be horizontal, and after the polymerizable liquid material is injected, the apparatus rotates at a high speed. After molding, the cylindrical substrate is taken out by moving one of the mold holding members C3 in the direction of arrow B.

In the manufacturing process shown in FIG. 1, first, a vinyl polymerizable liquid material, for example, a methyl methacrylate monomer is used as a radical polymerizable monomer, divinyl benzene is used as a polyfunctional vinyl compound, and azoisobutyro is used as a polymerization initiator. Nitrile was added and prepolymerized to a viscosity of 10 cp or more and 400 cp or less.
Pour into. This cylindrical mold usually has an inner diameter of at least 20 mm2.
The length is 200 mm or more and 2000 mm or less. This is rotated for each mold and is heated appropriately to promote uniform polymerization. After completion of the polymerization, the substrate is annealed and cooled to a temperature close to room temperature, the obtained substrate is taken out of the mold, cut, and optionally subjected to a surface processing step to complete the translucent substrate for an electrophotographic photosensitive member.

The above-mentioned centrifugal polymerization method preferably used in the present invention does not leave dice scratches and dust powder on the surface of the cylindrical substrate, and particularly the inner surface is formed into a natural surface obtained by centrifugal force, It forms an extremely smooth inner surface.

As a preferable material for producing the substrate of the present invention, a radical polymerizable monomer and, if necessary, a polyfunctional vinyl compound (crosslinkable monomer) are copolymerized in the presence of a radical polymerization initiator. Obtainable.

This will be described in more detail below.

The radically polymerizable monomers used in the present invention include styrene, α-methylstyrene, m-
Side chain alkyl-substituted styrene such as methylstyrene and p-methylstyrene, core alkyl-substituted styrene such as vinyltoluene, p-chlorostyrene, o-chlorostyrene, m-
Chlorostyrene, p-bromostyrene, o-bromostyrene, n-bromostyrene, 2,4-dichlorostyrene, 2,4-dibromostyrene, 4-chloro-α-methylstyrene, 4-bromo-α-methylstyrene, 2,
Halogenated styrene such as 4,6-trichlorostyrene, 2,4,6-tribromostyrene, pentachlorostyrene, pentabromostyrene, vinyl benzoate, 2-vinylnaphthalene, 4-vinylbiphenyl, 1,1'-diphenyl Aromatic vinyl monomers such as ethylene, acrylonitrile, methacrylonitrile, fumaronitrile, maleonitrile, vinyl cyanide monomers such as α-chloroacrylonitrile, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl Methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, stearyl methacrylate, Octyl methacrylate, cyclohexyl methacrylate, allyl methacrylate, dicyclopentanyl methacrylate, norbornyl methacrylate, adamantyl methacrylate, isobornyl methacrylate, phenoxyethyl methacrylate, phenyl methacrylate, benzyl methacrylate, naphthyl methacrylate, butoxyethyl methacrylate, methyl acrylate, ethyl acrylate (Meth) such as propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, stearyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, phenyl acrylate, benzyl acrylate, etc.
(Meth) acrylic acids such as alkyl acrylates, methacrylic acid and acrylic acid, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, OH group-containing (meth) acrylates such as tetrahydrofurfuryl (meth) acrylate, epoxy group-containing (meth) acrylates such as glycidyl (meth) acrylate, and N-containing such as N, N-diethylaminoethyl (meth) acrylate. (Meth) acrylates, butoxytriethylene glycol (meth) acrylate, ethoxydiethylene glycol (meth) acrylates, and other ether group-containing (meth) acrylates, maleic acid, maleic anhydride, dimethylmalate, dibutylmale Maleic acid, maleic acid esters such as dibenzyl malate, itaconic acid, itaconic anhydride, benzyl itaconate, itaconic acid such as dibenzyl itaconate, itaconic acid esters, fumaric acid, dimethyl fumarate, dibutyl fumarate Acid, fumaric acid esters such as diisopropyl fumarate, dibenzyl fumarate and dicyclohexyl fumarate, and other monomers such as vinyl acetate, vinyl chloride, vinylidene chloride, Nt-butylmaleimide,
N- such as laurylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, No-chlorophenylmaleimide and N-dimethylphenylmaleimide
Alkylmaleimides, N-phenylmaleimides and mixtures thereof are preferably used. More preferably, the radical polymerizable monomer contains methyl methacrylate in an amount of 20% by weight or more, preferably 40% by weight or more.

The polyfunctional vinyl compounds (crosslinker monomers) preferably used in the present invention include divinylbenzene, metadivinylbenzene, 4,4'-divinylbiphenyl, 3,3'-divinylbiphenyl, and 3,4'-divinyl. Biphenyl, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate,
Trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, divinyl phthalate, diallyl phthalate, divinyl isophthalate, diallyl isophthalate, divinyl terephthalate, diallyl terephthalate, diallyl naphthenate, triallyl isocyanurate, diallyl carbonate, diethylene glycol One or more selected from bisallyl carbonate and the like are used in combination as a crosslinking agent.

The amount of the crosslinking agent added is 0.05% of the total amount of the raw material monomers (radical polymerizable monomer + polyfunctional vinyl compound).
Used in the range of ９０90% by weight. If it is less than 0.05% by weight, the heat resistance is not satisfactory. If it is more than 90% by weight,
Hard but brittle resin may result in poor mechanical durability.

In the polymer resin for a substrate used in the present invention, the radical polymerization initiator used is not particularly limited, and the active radical is generated by an active energy ray such as visible light, infrared ray, ultraviolet ray, microwave, electron beam or heat. Whatever occurs is acceptable.

Benzoyl peroxide, diisopropylperoxydicarbonate, t-butylperoxy-2-ethylhexanoate, t-butylperoxypivalate, t-butylperoxydiisobut There are tyrates, lauroyl peroxide, t-butylperoxyacetate, t-butylperoxyoctoate, t-butylperoxybenzoate, di-t-butylperoxide, azobisisobutyronitrile (azoisobutyronitrile) and the like. .

As a radical polymerization initiator for generating an active radical by an activation energy ray, acetophenone,
Benzophenone, benzoin, benzoin methyl ether, 2-hydroxy-2-methyl-1-phenylpropan-1-one, hydroxycyclohexylphenyl ketone, methylphenylglyoxylate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzyl There are dimethyl ketal and the like, and they can be used alone or as a mixture when used.

The mixing ratio of the radical polymerization initiator varies depending on the type of the radical polymerization initiator, the type of the vinyl monomer, the polymerization curing temperature, and the like. Generally, the mixing ratio is based on 100 parts by weight of the copolymerizable vinyl monomer. And preferably 0.01 to 8 parts by weight, particularly preferably 0.1 to 5 parts by weight. If the mixing ratio of the radical polymerization initiator is less than 0.01 part by weight, it may take a long time for polymerization and curing. If the amount of the polymerization initiator exceeds 8 parts by weight, the polymer may become brittle or colored.

In addition to the above-mentioned vinyl polymer resin, the present invention also relates to a substrate prepared by injection molding, extrusion molding or injection blow using, for example, polyester, polycarbonate, polyamide, polysulfone, polymethylvinylpentene or the like. Can also be used favorably.

On the surface of the substrate, a coating layer other than the conductive layer is formed by a known method. For example, by a vapor deposition method, a dip coating method, a ring coating method, a spray coating method, or a circular amount control type coating method, a charge generation layer is usually formed as a photosensitive layer on a conductive layer on a substrate surface, and a charge transport layer is further formed thereon. Form.

Prior to coating the photosensitive layer, to improve the adhesion and coating properties of the photosensitive layer, cover defects on the substrate surface and the conductive layer, and improve the charge injection property from the conductive layer to the charge generating layer, etc. An intermediate layer (undercoat layer) is often provided below the charge generation layer. Materials include polyamide, copolymerizable nylon, casein, polyvinyl alcohol, cellulose,
Resin intermediate layer of gelatin or the like, or JP-A-9-68887
As described in Japanese Patent Publication No. 0, a curable intermediate layer using an organic metal chelate compound or the like is well known. These are dissolved in various organic solvents and the like, and applied on a substrate so that the film thickness becomes about 0.01 to 5 μm.

In the formation of the photosensitive layer, as described above, the organic photoconductor layer as the photosensitive layer, in particular, the charge transport material (CT)
M) and a charge-separating substance (CGM), and is preferably formed by applying a function-separated type, particularly, an organic photoreceptor of a type in which each is separately laminated.

The charge generation layer contains, as a main component, a charge generation substance which generates charges by light irradiation, and if necessary, contains a known binder, plasticizer, and sensitizer, and has a thickness of 1.0 μm or less ( (Dry film thickness) on the conductive layer or the undercoat layer.

As the charge generating substance, perylene pigments,
Polycyclic quinone pigments, phthalocyanine pigments, metal phthalocyanine pigments, squarium dyes, azurenium dyes, thiapyrylium dyes and carbazole skeletons, styrylstilbene skeletons, triphenylamine skeletons, dibenzothiophene skeletons, oxadiazole skeletons, fluorenone skeletons, bisstilbenes An azo pigment having a skeleton, a distyryloxadiazole skeleton or a distyrylcarbazole skeleton is exemplified.

The charge transport layer contains, as essential components, a charge transport material capable of accepting and transporting charges generated by the charge generating material and a binder, and if necessary, a known leveling agent, plasticizer, sensitizer, and the like. Agent, etc., and dry film thickness of 5 to 70
It is applied on the charge generation layer to a thickness of μm.

Examples of the charge transport material include poly-N-vinylcarbazole and its derivatives, poly-γ-carbazolylethylglutarate and its derivatives, pyrene-formaldehyde condensate and its derivatives, polyvinylpyrene, polyvinylphenanthrene, and oxazole derivatives Oxodiazole derivatives, imidazole derivatives, 9- (p-diethylaminostyryl) anthracene, 1,1-bis (4-dibenzylaminophenyl) propane, styrylanthracene, styrylpyrazolin, phenylhydrazones, hydrazone derivatives, etc. Donor substance or fluorenone derivative, dibenzothiophene derivative, indenothiophene derivative, phenanthrenequinone derivative, indenopyridine derivative, thioxanthone derivative, phenazine oxide derivative , Tetracyanoethylene, tetracyanoquinodimethane, Puromaniru, chloranil, electron-accepting substance such as benzoquinone, and the like.

The binder constituting the charge transporting layer may be any one which is compatible with the charge transporting substance, such as polycarbonate, polyvinyl butyral, polyamide, polyester, polyketone, epoxy resin, polyurethane, polyvinyl ketone, and polystyrene. , Polyacrylamide, phenol resin, phenoxy resin and the like.

Next, an embodiment of the image forming apparatus and the image forming method of the present invention will be described with reference to the color image forming apparatus shown in FIG. FIG. 3 is a cross-sectional configuration view of a color image forming apparatus showing an example of an image forming apparatus to which the electrophotographic photosensitive member manufactured using the above-described translucent resin substrate of the present invention is applied.

Reference numeral 10 denotes a photosensitive member which is a drum-shaped electrostatic image forming member, and the transparent member of the present invention is provided on the outer periphery of a cylindrical substrate formed of a highly transparent cross-linked polymethyl methacrylate polymer resin. A functionally separated organic photosensitive layer comprising a conductive layer, a charge generation layer and a charge transport layer is formed. 110Y, 110M, 110C and 110K are corona chargers used in image forming processes of yellow (Y), magenta (M), cyan (C) and black (K), respectively. In order to hold a charge of a predetermined potential, a charging action is performed by corona discharge to give a uniform potential to the photoconductor 10.

12Y, 12M, 12C and 12K are
FL (phosphor emission), EL (electroluminescence), PL (plasma discharge), LED (light emitting diode), and lamp and light shutter function in which light emitting elements arranged in the axial direction of the photoconductor 10 are arranged in a line. (Magneto-optical effect optical shutter array) in which elements with
PLZT (Transmissive piezoelectric element shutter array), LCS
An image of each color read by a separate image reading device using an exposure optical system that is an image exposure device configured as a unit including an exposure element such as a (liquid crystal shutter) and a selfoc lens as an equal-magnification image forming element. The signals are sequentially taken out of the memory and the exposure optical systems 12Y, 12M, 1
2C and 12K are respectively input as electric signals. The above-mentioned exposure optical systems 12Y, 12M, 12C and 1
Each 2K is attached to a cylindrical holding member 20 and housed inside the substrate of the photoreceptor 10.

13Y, 13M, 13C and 13K are
A developing device which is a developing device using a non-contact developing method for accommodating respective developers of yellow (Y), magenta (M), cyan (C) and black (K). A developing sleeve that rotates in the same direction while maintaining a predetermined gap is provided.

The developing units 13Y, 13M, 13C and 13K are provided with the above-described corona charging devices 110Y, 110Y.
M, 110C and 110K charging, exposure optical system 1
The electrostatic latent image on the photoconductor 10 formed by the image exposure by 2Y, 12M, 12C and 12K is reversely developed in a non-contact state by applying a developing bias voltage.

The image of the original is read by an image reading apparatus separate from the present apparatus, and the image read by the image pickup device or the image edited by the computer is temporarily converted into image signals for each of Y, M, C and K colors. Stored and stored in memory.

At the start of image recording, the photosensitive member 10 is rotated clockwise by the start of the photosensitive member driving motor, and at the same time, the photosensitive member 10 is rotated by the charging action of the corona charging device 110Y.
Is started.

After the photosensitive member 10 is applied with a potential, the exposure optical system 12Y starts exposure with an electrical signal corresponding to a first color signal, that is, an image signal of yellow (Y), and the photosensitive drum 10 is rotated and scanned by rotating the drum. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface.

The latent image is reversal-developed by the developing device 13Y in a state where the developer on the developing sleeve is not in contact with the developer, and a yellow (Y) toner image is formed in accordance with the rotation of the photosensitive drum 10.

Next, the photosensitive drum 10 is further provided with a corona charging device 110M on the yellow (Y) toner image.
The exposure is performed by an electric signal corresponding to the second color signal of the exposure optical system 12M, that is, the image signal of magenta (M), and the non-contact reversal development is performed by the developing unit 13M. A magenta (M) toner image is sequentially formed on the yellow (Y) toner image.

By the same process, the corona charging device 11
0C, a cyan (C) toner image corresponding to the third color signal by the exposure optical system 12C and the developing device 13C, and a fourth color signal by the corona charging device 110K, the exposure optical system 12K and the developing device 13K. Corresponding black (K) toner images are sequentially superposed, and a color toner image is formed on the peripheral surface within one rotation of the photosensitive drum 10.

These exposure optical systems 12Y, 12M, 12C
Exposure of the organic photosensitive layer of the photoreceptor drum 10 at the temperature of 12 K and 12 K is performed from the inside of the substrate through the transparent substrate described above. Therefore, the exposure of the image corresponding to the second, third, and fourth color signals is performed without any influence from the previously formed toner image, and the same exposure as the image corresponding to the first color signal is performed. It is possible to form an electrostatic latent image. In order to stabilize the temperature inside the photosensitive drum and prevent the temperature from rising due to the heat generated by the exposure optical systems 12Y, 12M, 12C and 12K, a material having good heat conductivity is used for the holding member 20. When the temperature is high, measures such as radiating heat to the outside through a heat pipe can be taken to a level where no problem is caused.

Thus, the color toner image formed on the peripheral surface of the photosensitive drum is sent out from the paper feed cassette 15 by the feed roller 15a in the transfer device 14a, and is sent to the timing roller 16 by the feed roller pairs 15b and 15c. The sheet is conveyed, and is transferred onto a transfer sheet P, which is a transfer material fed in synchronization with the toner image on the photoconductor 10, by driving the timing roller 16.

The transfer paper P on which the toner image has been transferred is separated from the peripheral surface of the drum by the removal of the charge in the charge eliminator 14b, and then is conveyed by the transport driving roller 14c and the driven roller 14d.
The fixing device 17 is moved by the conveying belt 14e stretched between the fixing belts.
Transported to The fixing roller 17 in the fixing device 17
a, the toner is heated and pressed between the pressure rollers 17b to fuse and fix the toner on the transfer paper P, and then a pair of fixing exit rollers 17d
Is discharged from the fixing device 17 by the
The sheet is conveyed by 8a and is discharged onto a discharge tray 200 at the top of the apparatus via the discharge roller 18.

On the other hand, the photosensitive member 10 from which the transfer paper is separated is cleaned by a cleaning blade 19a in a cleaning device 19.
The surface of the photoreceptor 10 is rubbed to remove residual toner and is cleaned to continue formation of a toner image of a document image, or to temporarily stop and form a toner image of a new document image. The waste toner scraped off by the cleaning blade 19a is discharged to a waste toner container (not shown) by the toner conveying screw 19b.

Since the photosensitive member 10 accommodates the exposure optical system therein, even if the diameter of the drum is relatively small,
The plurality of corona charging devices 110 described above are provided on the outer peripheral surface thereof.
Y, 110M, 110C and 110K, developing unit 13
Y, 13M, 13C and 13K can be provided, and the volume of the apparatus can be made compact by using a small-diameter drum having an outer diameter of 30 mm to 150 mm.

Although the embodiment of the present invention has been described for the case of color superimposed image formation by non-contact development, it can be similarly applied to monochrome image formation and contact development.

The photosensitive member of the present invention is disclosed in Japanese Patent Application Laid-Open No. 6-2306.
It is easily understood that the present invention can be applied to a system which does not require corona charging as described in Japanese Patent Publication No. 34-34.

[0070]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 (Examples and Comparative Examples) Preparation of Cylindrical Substrate In a monomer mixture consisting of methyl methacrylate / α-styrene / divinylbenzene (85/7/8 parts by weight),
Using benzoyl peroxide as a polymerization initiator, the substrate obtained by the centrifugal polymerization method was subjected to edge cutting to obtain an outer diameter of 10%.
A cylindrical substrate having a length of 0 mm and a length of 360 mm was obtained. After each buffing, it was washed and dried.

With respect to the cylindrical substrate obtained as described above,
The coating liquid composition for the conductive layer was dried to a thickness of 1.5 μm as follows.
And heat-treated at 90 ° C. for 30 minutes.

Separately, for a solubility test, a PET base was wound around a cylindrical substrate, and a coating solution composition for a conductive layer was applied by dip coating in the same manner as described above, followed by heat treatment.

2. Conductive layer coating liquid composition Methyl methacrylate / 2-hydroxyethyl methacrylate / itaconic acid (80/15/5 mol ratio) copolymer 50 g ITO powder 380 g Isophorone / toluene (10/5 vol ratio) 1000 g The coating liquid composition UCL-1 for the intermediate layer (UCL) was applied to a dry film thickness of 0.5 μm as described above.

[0075] 3. UCL-1 coating solution composition Copolymer nylon resin (CM-8000, manufactured by Toray Industries, Inc.) 3 g Methanol / n-butanol = 10/1 (vol ratio) 1000 ml Coating solution composition for CGL layer as described below on UCL coated above CGL-1 was applied to a dry film thickness of 0.25 μm.

[0076] 4. CGL-1 coating liquid composition Y-type titanyl phthalocyanine 20 g Silicone resin (KR-5240 manufactured by Shin-Etsu Chemical Co., Ltd.) 40 g 2-butanone (the above coating liquid composition dispersed for 10 hours using a sand mill) 1000 g CGL coated above A coating liquid composition CTL-1 of a CTL layer is applied thereon so as to have a dry film thickness of 25 μm as described below, and is subjected to a heat treatment at 90 ° C. for 1 hour.
o. 1 was obtained.

[0077] 5. CTL-1 coating solution composition CTM-1 80 g Polycarbonate (Z-200 manufactured by Mitsubishi Gas Chemical Company) 120 g 1,2-dichloroethane 1000 g

[0078]

Embedded image

Comparative Example 1 A comparative photoconductor was prepared in the same manner as in Example 1 except that the conductive layer was heat-treated at 80 ° C. for 30 minutes. This comparative example photosensitive drum was designated as No. 1S.

Comparative Example 2 A glycidyl methacrylate / methacrylic acid / methyl methacrylate (20/20/60 mol ratio) copolymer was used as the photosensitive member in place of the conductive layer resin of Example 1, and the heat treatment was performed at 100 ° C.・ Except for 30min
It was produced in the same manner as in Example 1. This comparative example photosensitive drum was designated as No. 2S.

Examples 2 and 3 Photoreceptors were prepared in the same manner as in Example 1 except that the kind and amount ratio of the conductive layer polymer were changed as shown in Table 1. Each of these photosensitive drum Nos. 2 and No. 3 is assumed.

Example 4 Methyl methacrylate / α-styrene / ethylene glycol dimethacrylate (80 /
Example 1 except that a copolymer (20/20 parts by weight) was used.
A photoreceptor was produced in the same manner as described above. The photosensitive drum No. 4
And

Performance Evaluation Dissolution rate of conductive layer Measured by the method described above.

2. Cellophane tape peeling test A checkerboard-shaped slit wound is made on the test object with a knife, and cellophane tape is stuck thereon and stripped off with a certain force. The results are expressed as the area% of the stripped part.

3. Actual Photographic Test An electrophotographic internal exposure type image forming apparatus having the structure shown in FIG. Nos. 1 to 4 and Nos.
1S and 2S were mounted, 10,000 images were output, and image evaluation was performed. Regarding the image quality, black spots, image defects and the like were observed. The reflection density on a white background was measured, and the degree of increase in the residual potential was observed.

Table 1 shows the results.

[0087]

[Table 1]

Table 1 shows that when the dissolution rate is within the range of the present invention, the adhesiveness is excellent, there is no image defect, no fogging occurs due to an increase in residual potential, and the durability and image quality are excellent.

[0089]

According to the present invention, in an electrophotographic photosensitive member in which an organic photosensitive layer is coated on a resin substrate, the lower conductive layer does not dissolve, particularly in the case of multilayering, and the adhesion performance between the substrate and the conductive layer is improved. To provide an electrophotographic photoreceptor which is favorable, has good potential stability over time, has good repeated use characteristics, and does not cause image defects, and a method of manufacturing the same, and an image forming method and an image forming apparatus using the same. I can do it.

[Brief description of the drawings]

FIG. 1 is a process chart of a method for producing a translucent substrate for an electrophotographic photosensitive member according to the present invention.

FIG. 2 is a cross-sectional view illustrating an example of a manufacturing apparatus.

FIG. 3 is a cross-sectional configuration diagram of the image forming apparatus of the present invention.

[Explanation of symbols]

10 Photoconductor (Photoconductor Drum) 12Y, 12M, 12C, 12K Yellow, Magenta, Cyan, Black Exposure Optical System (Exposure Device) 13Y, 13M, 13C, 13K Yellow, Magenta, Cyan, Black Developer 110Y, 110M , 110C, 110K yellow,
Magenta, cyan, and black corona charging device 15 Paper cassette 16 Timing roller 17 Fixing device 19 Cleaning device P Transfer paper

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H030 BB02 BB23 BB44 BB71 2H068 AA37 AA43 AA45 AA48 AA52 BB06 CA40 EA16 FB11 FC06 FC08

Claims (8)

[Claims] 1. A method for producing an electrophotographic photoreceptor, in which a conductive layer and an organic photosensitive layer are sequentially coated on a resin substrate, wherein the coating liquid for the conductive layer contains conductive fine particles and a binder resin.
An electrophotographic photoreceptor, wherein the resin is a self-crosslinkable (meth) acrylic acid-based resin, and the coating liquid has a methyl ethyl ketone dissolution rate of 3.0 to 90% by weight after heat treatment at 80 ° C. for 1 hour. Manufacturing method. 2. An electrophotographic photosensitive member in which a conductive layer and an organic photosensitive layer are sequentially coated on a resin substrate, wherein the coating liquid for the conductive layer contains conductive fine particles and a binder resin, and the resin has a self-crosslinking property. An electrophotographic photoreceptor, which is a (meth) acrylic acid-based resin, wherein the coating liquid has a methyl ethyl ketone dissolution rate of 3.0 to 90% by weight when heat-treated at 80 ° C. for 1 hour. 3. The electrophotographic photoreceptor according to claim 2, wherein the resin substrate is made of a vinyl polymer resin. 4. The electrophotographic photoconductor according to claim 2, wherein the resin substrate is made of a crosslinkable polymer resin. 5. The electrophotographic photosensitive member according to claim 2, wherein the resin substrate is produced by a centrifugal polymerization method. 6. The electrophotographic photosensitive member according to claim 2, which is a photosensitive member for internal exposure. 7. A method for uniformly charging the surface of an electrophotographic photoreceptor, repeating image exposure and color development to form a multicolor superimposed image, and performing batch transfer, separation, fixing, and photoreceptor cleaning to form an image. An image forming apparatus for forming an image by using the electrophotographic photosensitive member according to claim 2, exposing the image through a light-transmitting substrate, and forming an image by non-contact development. 8. A process for uniformly charging the surface of an electrophotographic photoreceptor, an image exposure step, and a color development step to form a multicolor superimposed image, a batch transfer step, a separation step, a fixing step, and a photoreceptor. In an image forming method which passes through each step of cleaning, the electrophotographic photosensitive member according to claim 2 is used,
An image forming method, wherein an image is exposed through a translucent substrate and an image is formed by non-contact development.