JPH11288117A - Light-transmissive substrate for electrophotographic photoreceptor, manufacture thereof and electrophotographic photoreceptor, image forming method and image forming device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-transmissive substrate for an electrophotographic photoreceptor and its producing method in which a photoreceptor substrate has excellent characteristics such as good image quality of finish image without out-of-focus images or distortion of images when the images are exposed by transmitting light through the photoreceptor substrate and to provide the electrophotographic photoreceptor, an image forming method and an image forming device using this substrate. SOLUTION: This light-transmissive substrate of an electrophotographic photoreceptor is formed from a polymer resin and is formed to have <=0.1 difference in the refractive index of the substrate depending on the position. If an interface with >0.1 difference in the refractive index is present, exposure light is partly diffracted on the interface to cause an out-of-focus image or distortion. Especially when a copolymer resin or a blended resin is used, the difference in the refractive index is easily produced because the copolymn. ratio or blending ratio differs between the surface and the inner part. When the body is formed by injection molding, the difference in the refractive index is easily produced because of the difference due to a working process such as orientation, cooling and heating rates and pressurizing between the surface part and the inner part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a translucent substrate for an electrophotographic photosensitive member used for monochrome and color copiers, monochrome and color printers and the like, a method for producing the same, and an electrophotographic photosensitive member and an image using the same. The present invention relates to a forming method and an image forming apparatus.

[0002]

2. Description of the Related Art In an image forming apparatus for forming an image by an electrophotographic system, charging, image exposure and development are performed on a rotating drum or belt-like electrostatic image forming body (photoconductor) to form the electrostatic image. A toner image is formed on a body, and the toner image is transferred to a transfer material and fixed. In order to fulfill this function, the electrostatic image forming body is maintained without changing the distance and pressure contact with the charger, exposure device, developing device, transfer device, static eliminator, cleaning device, etc. disposed around it. It must be maintained at a predetermined timing and move at a constant speed. 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 out this series of movements and to efficiently use expensive members such as photoconductors, practically used photoconductors have a photoconductor in which a photoconductive layer is provided on the peripheral surface of an almost cylindrical substrate. Drums are used. As the material of the cylindrical substrate, a metal material such as aluminum is often used. However, there is a limit to cost reduction in forming a cylindrical substrate by machining using a metal material.

[0003] On the other hand, plastic is considered to be a preferable material because of its light weight and low cost. However, it is not easy to produce a cylindrical electrostatic image forming member with high precision and industrially efficiently. The major factor is that a simple method for making a cylindrical substrate having a required size and shape with a roundness of ± 50 μm has not been found.
For this reason, conventionally, after manufacturing the cylindrical substrate, the precision has to be secured by machining such as cutting and polishing the surface, which leads to a decrease in productivity and an increase in cost. In addition, it has a disadvantage that it is weak to heat and solvents, and in addition to the accuracy of the surface of the substrate, strength and deformation due to aging are also problems.

As will be described in detail later, for an image forming apparatus configured to perform image exposure from the inside of the electrophotographic photosensitive member, the cylindrical substrate of the electrophotographic photosensitive member is exposed to light exposed from the inside. It must be transparent and have a uniform refractive index, and metal cannot be used as the base material. Therefore, there is a problem that the image forming method of exposing the image from the inside cannot be practically used even if the apparatus configuration is excellent. As described above, an excellent translucent substrate for an image forming apparatus has been desired, but has not yet been put to practical use, and thus has a configuration in which image exposure is performed from the inside of the electrophotographic photosensitive member. At present, some image forming apparatuses cannot be put into practical use.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photoreceptor substrate which is excellent in that when exposed to light and image-exposed, there is no image blur, the image is not distorted, and the quality of the finished image is good. An object of the present invention is to provide a translucent substrate for an electrophotographic photosensitive member having characteristics and a method of manufacturing the same, an electrophotographic photosensitive member using the same, an image forming method, and an image forming apparatus.

[0006]

The object of the present invention is attained by adopting one of the following constitutions.

[1] In a light-transmitting substrate for an electrophotographic photosensitive member, the light-transmitting substrate is formed of a polymer resin, and a difference in a refractive index of the light-transmitting substrate depending on a location is within 0.1. A translucent substrate for an electrophotographic photoreceptor, comprising:

[2] The transparent substrate for an electrophotographic photosensitive member according to [1], wherein the polymer resin is a vinyl polymer resin.

[3] The electrophotograph according to [1], wherein the polymer resin forming the light-transmitting substrate is synthesized from a monomer having a crosslinking property and a monomer having no crosslinking property. Transparent substrate for photoreceptor.

[4] The translucent substrate for an electrophotographic photosensitive member according to [1], wherein the polymer resin forming the translucent substrate is used by blending plural kinds of resins.

[5] In the method for producing a light-transmitting substrate for an electrophotographic photosensitive member, the light-transmitting substrate is formed of a polymer resin, and the difference in the refractive index of the light-transmitting substrate is within 0.1. A method for producing a translucent substrate for an electrophotographic photosensitive member, characterized by comprising:

[6] The method for producing a light-transmitting substrate for an electrophotographic photosensitive member according to [5], wherein the light-transmitting substrate is produced by a centrifugal polymerization method.

[7] In an electrophotographic photosensitive member having a light-transmitting substrate provided with a conductive layer and a photosensitive layer, the light-transmitting substrate is formed of a polymer resin, and the difference in the refractive index of the light-transmitting substrate is reduced. An electrophotographic photoreceptor characterized by being within 0.1.

[8] The electrophotographic photosensitive member according to [7], which is used for internal exposure for exposing through a light transmitting substrate.

[0015]

[9] The surface of the electrophotographic photoreceptor is uniformly charged, image exposure and color development are repeated to form a multicolor superimposed image, and the image is formed through batch transfer, separation, fixing, and photoreceptor cleaning steps. In an image forming apparatus, an electrophotographic photoreceptor uses a photoreceptor obtained by providing a conductive layer and a photosensitive layer on a translucent substrate having a difference in refractive index of 0.1 or less. An image forming apparatus, which performs image exposure and forms an image by non-contact development.

[10] 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 transfer step, a separating step, a fixing step, and a photosensitive step. In the image forming method including the steps of body cleaning, the light-transmitting substrate is formed of a polymer resin, and the electrophotographic photoreceptor has a conductive layer on the light-transmitting substrate having a difference in refractive index within 0.1. An image forming method using a photoreceptor provided with a photosensitive layer, exposing the image to light through a translucent substrate, and forming an image by non-contact development.

On the boundary surface where the difference in refractive index is larger than 0.1, the exposure light is partially refracted, which causes image blur and distortion.

Particularly, in the case of a copolymer resin or a blended resin, a difference in the refractive index tends to occur because the copolymerization ratio and the blend ratio between the surface and the interior are different. In addition, in the case of injection molding, a difference in refractive index tends to occur due to a difference due to the orientation between the surface and the inside, or a processing process such as cooling, heating speed, and pressure.

The refractive index specified in the present invention can be measured by a well-known method using an instrument such as an ellipsometry method or Abbe's refractometer. Further, in the measurement, it is only necessary to measure by a method that can identify both the one showing the maximum refractive index and the one showing the minimum refractive index, but it is necessary to measure at least both ends and the center of the part related to image formation of the substrate. is there. In each case, the measurement is performed on the outer surface side and the inner surface side of the substrate.

That is, if the difference between the maximum value and the minimum value of the refractive index is more than 0.1, the way in which light passing through the light-transmitting substrate is refracted will be different. Size, which also affects the quality of the final image.

The translucent substrate for an electrophotographic photosensitive member according to the present invention is produced by a centrifugal polymerization method, injection molding, extrusion molding or the like. The production by the centrifugal polymerization method, which is a typical production method, will be specifically described as shown in FIG.
FIG. 2 shows an example of the manufacturing apparatus. In the manufacturing apparatus of FIG. 2, C1 is a cylindrical mold and the inner surface is polished to form a highly accurate cylindrical surface. 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 the molding, the cylindrical substrate is taken out by moving the one mold holding member C3 in the direction of arrow B.

In the manufacturing process shown in FIG. 1, first, a vinyl polymerizable liquid material, for example, methyl methacrylate monomer is used, and a polymerization initiator is added thereto to adjust the viscosity to 1%.
It is adjusted to a state of 0 cp or more and 400 cp or less, and poured into a cylindrical mold C1. This cylindrical mold usually has an inner diameter of 20 mm to 200 mm and a length of 200 mm to 2000 m.
m or less. This is rotated together with the mold, and is heated appropriately to promote uniform polymerization. After completion of the polymerization, the substrate is cooled to a temperature close to room temperature, the obtained substrate is taken out of the mold, cut, and if necessary, subjected to a finishing 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 on the surface of the cylindrical substrate, and particularly the inner surface is formed into a natural surface obtained by centrifugal force, and is extremely smooth such as a glass surface. Forms a smooth inner surface.

The preferred materials for producing the substrate of the present invention include a radically polymerizable monomer (monomer, a monomer having no crosslinkability) and a polyfunctional vinyl compound (a monomer having a crosslinkability). And in the presence of a radical polymerization initiator. It is also preferable to blend a plurality of types of resins.

The details will be described 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, m-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, Cutyl 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 , Fumaric acid esters such as diisopropyl fumarate, dibenzyl fumarate, dicyclohexyl fumarate, and the like; and other monomers such as vinyl acetate, vinyl chloride, vinylidene chloride, N-alkylmaleimides,
-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 compound (crosslinkable monomer) used in the present invention includes divinylbenzene, metadivinylbenzene, 4,4'-divinylbiphenyl,
3,3'-divinyl biphenyl, 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,
One or more selected from diethylene glycol bisallyl carbonate and the like are used in combination as a crosslinking agent. The amount of the cross-linking agent added depends on the total amount of the raw material monomers (radical polymerizable monomer +
It is used in the range of 0.05 to 90% by weight of the polyfunctional vinyl compound). If it is less than 0.05% by weight, the heat resistance is not satisfactory. If the content is more than 90% by weight, a hard but brittle polymer is obtained, resulting 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.

Radical polymerization initiators that generate active radicals by heat include benzoyl peroxide, diisopropylperoxydicarbonate, t-butylperoxy-2-ethylhexanoate, t-butylperoxypivalate, and t-butylperoxydiisobu. There are tyrates, lauroyl peroxide, t-butylperoxyacetate, t-butylperoxyoctoate, t-butylperoxybenzoate, di-t-butylperoxide, azobisisobutyronitrile 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-based monomer, the polymerization curing temperature, and the like. In general, the mixing ratio is based on 100 parts by weight of the copolymerizable vinyl-based 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 takes a long time for the polymerization to cure or the polymerization is not completed, which is not preferable. Further, when the compounding ratio of the polymerization initiator exceeds 8 parts by weight, the polymer becomes brittle or colored, which is not preferable.

The non-vinyl polymer resins constituting the substrate of the present invention include polyamide, polyimide, epoxy resin, polycarbonate, polysulfone, polyethersulfone, polyester, polyarylate, polyphenylene oxide, polybutylene terephthalate, and polyethylene terephthalate. And polymethylpentene.
After injection molding or extrusion molding of these polymer resins, the surface is polished or cut to obtain a desired Rz, whereby the transparent cylindrical substrate of the present invention can be produced.

A non-crosslinked vinyl polymer can also be used as a base material in the above-mentioned molding method.

Next, the case where the light transmitting substrate of the present invention is used for an electrophotographic photosensitive member will be described. The cylindrical substrate of the present invention has a smooth surface, especially in the case of using a polymer of methyl methacrylate, and the transparency is extremely high and the strength is high. It is suitable for an image forming apparatus employing a mechanism for performing exposure from the inside.

A typical one is an electrophotographic photosensitive member having a conductive layer and a photoconductor photosensitive layer provided on the surface of a cylindrical substrate. Conventionally, an electrophotographic photosensitive member has been used for providing a conductive layer and a photoconductor photosensitive layer. The method can be widely used.

That is, the transparent conductive layer is formed by vapor deposition or sputtering of a metal or metal oxide such as aluminum or ITO (indium tin oxide), or by mixing ITO or alumina conductive fine particles with a resin. A typical example thereof is the formation of a coating film of a conductive resin by using a resin.

For improving the adhesion of the photosensitive layer, improving the coating property, covering defects on the substrate, and improving the charge injection property from the substrate to the charge generation layer, an intermediate layer (undercoat layer) is provided below the charge generation layer. May be provided. Examples of the material of the undercoat layer include alcohol-soluble polyamide, copolymerized nylon, alkoxymethylated nylon, vinyl chloride-vinyl acetate copolymer, casein, polyvinyl alcohol, cellulose, gelatin, and metal as described in JP-A-9-68870. Alkoxide,
A curable undercoat layer using an organic metal chelate and a silane coupling agent is used. These have a thickness of 0.01 to 5 μm.
m.

In forming the photosensitive layer, an inorganic photoconductor layer may be formed by vapor deposition or the like. However, an organic photoconductor layer, in particular, a function separation type containing both a charge transport material and a charge generation material, may be used. In particular, it is preferable to form by applying an organic photoreceptor of a type in which each is separately laminated.

The charge generation layer (CGL) is formed by dispersing a charge generation material (CGM) in a binder resin as required. Examples of CGM include metal or metal-free phthalocyanine compounds, azo compounds such as bisazo compounds and trisazo compounds, squarium compounds, azurenium compounds, perylene compounds, indico compounds, quinacridone compounds, polycyclic quinone compounds, cyanine dyes, xanthene dyes, Examples include, but are not limited to, charge transfer complexes comprising poly-N-vinylcarbazole and trinitrofluorenone. These may be used as a mixture of two or more as necessary. However, in order to achieve the object of the present invention at the highest level, titanyl phthalocyanine (TiOPc), a kind of perylene compound, an imidazole perylene compound or a kind of metal phthalocyanine compound, is preferable.

As the binder resin usable for the charge generation layer, for example, polystyrene resin, polyethylene resin, polypropylene resin, polyacryl resin, polymethacryl resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinyl butyral resin, Epoxy resins, polyurethane resins, polyphenol resins, polyester resins, polyalkyd resins, polycarbonate resins, polysilicone resins, polymelamine resins, and copolymer resins containing two or more of the repeating units of these resins, for example, vinyl chloride-acetic acid Vinyl copolymer resin, vinyl chloride-vinyl acetate-maleic anhydride copolymer resin, and high-molecular organic semiconductor such as poly-N-vinyl carbazole,
And the like, but are not limited thereto. Among the above, when the imidazole perylene compound is used as the CGM, a preferred binder is polyvinyl butyral resin, and a preferred binder when using TiOPc is a polysilicone resin and a polyvinyl butyral resin, or a mixture of both. No.

The charge transport layer (CTL) is composed of a charge transport material (CTM) alone or together with a binder resin. Examples of the CTM include carbazole derivatives, oxazole derivatives, oxadiazole derivatives, thiazole derivatives, thiadiazole derivatives, triazole derivatives, imidazole derivatives, imidazolone derivatives, imidazolidine derivatives, bisimidazolidine derivatives, styryl compounds, hydrazone compounds, pyrazoline derivatives, and oxazolone. Derivatives, benzimidazole derivatives, quinazoline derivatives, benzofuran derivatives, acridine derivatives,
Phenazine derivatives, aminostilbene derivatives, triarylamine derivatives, phenylenediamine derivatives, stilbene derivatives, benzidine derivatives, poly-N-vinylcarbazole, poly-1-vinylpyrene, poly-9-vinylanthracene, but are not limited thereto. Not necessarily. These may be used alone or in combination of two or more.

As the binder resin usable for the charge transport layer, for example, a polycarbonate resin, a polyacrylate resin, a polyester resin, a polystyrene resin,
Examples thereof include, but are not limited to, styrene-acrylonitrile copolymer resin, polymethacrylate resin, and styrene-methacrylate copolymer resin.

Further, in order to reduce fatigue deterioration upon repeated use or to improve durability, each of the layers of the photoreceptor is provided with a conventionally known antioxidant, ultraviolet absorber, electron-accepting substance and surface. An environment-dependent reducing agent such as a modifier and a plasticizer can be added in an appropriate amount as needed.

Further, in order to improve durability, a non-photosensitive layer such as an intermediate layer (undercoat layer) or a protective layer may be provided in addition to the photosensitive layer, if necessary.

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 cylindrical substrate of the present invention is applied.

Reference numeral 10 denotes a photosensitive member which is a drum-shaped electrostatic charge image forming body, and a transparent conductive layer and a charge generating layer are formed on the outer periphery of a cylindrical substrate formed of a highly transparent polymethyl methacrylate polymer resin. And a charge-transporting layer. 110Y, 11
Reference numerals 0M, 110C, and 110K denote corona charging devices used in image forming processes of yellow (Y), magenta (M), cyan (C), and black (K).
In order to maintain a predetermined potential charge on the organic photosensitive layer 0, a charging action is performed by corona discharge, and a uniform potential is applied 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.

The developing devices 13Y, 13M, 13C and 13K are developing devices using non-contact developing methods for accommodating yellow (Y), magenta (M), cyan (C) and black (K) developers. And a developing sleeve that rotates in the same direction while maintaining a predetermined gap with respect to the peripheral surface of the photoconductor 10.

The developing units 13Y, 13M, 13C and 13K are provided with the corona charging devices 110Y, 110
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.

An original image is read out by an image reading device separate from the present device, and an image read by an image sensor or an image edited by a computer is once converted into image signals for respective colors of Y, M, C and K. 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 charged by the charging action of the corona charging device 110Y.
Is started.

After the photoreceptor 10 is applied with a potential, the exposure optical system 12Y starts exposure with an electric signal corresponding to a first color signal, that is, an image signal of yellow (Y). 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, 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 charger 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 superimposed 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 unit 14a, and is sent to the timing roller 16 by the pair of transport rollers 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 to 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 drive roller 14c and the driven roller 14d.
The fixing device 17 is moved by the conveying belt 14e stretched between the fixing belts.
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 photosensitive drum 10 provided with the photosensitive layer on the cylindrical substrate of the present invention described above is conveyed by the discharge roller 8a and discharged onto the discharge tray 200 at the upper portion of the apparatus via the discharge roller 18. A clear and very good image was obtained.

On the other hand, the photosensitive member 10 from which the transfer paper has been separated is cleaned by a cleaning device 19 with a cleaning blade 19a.
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.

The photosensitive member 10 has a relatively small drum diameter because the exposure optical system is housed inside the photosensitive member 10.
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 example of forming a color image has been described above, in the case of forming a monochrome image, contact development may be performed.

The substrate of the present invention is disclosed in JP-A-6-23063.
It is easily understood that the present invention is also applied to a system which does not require corona charging as described in Japanese Patent Application Laid-Open No. 4 (1994) -208.

[0063]

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 A mixture of benzyl methacrylate (BzMA) monomer, methyl methacrylate (MMA) monomer and divinylbenzene in a blending ratio of 20/80/5 (monomer ratio) was mixed with azobisisobutyronitrile ( AIBN)
Was added, and the mixture was heated at 50 ° C. for 3 hours to carry out preliminary polymerization to obtain a syrup-like polymerizable liquid material having a viscosity of about 100 cp. This polymerizable liquid material was mixed well, poured into a cylindrical mold having an inner diameter of 100 mm and a length of 800 mm, and the mold was cooled to 500 RPM.
The entire mold was subjected to a heat treatment at 70 ° C. for 9 hours while being brought into close contact with the inner wall of the mold by centrifugal force to polymerize. The obtained substrate was annealed at a rate of 0.2 ° C./min to room temperature, and then removed from the mold.
The obtained substrate was subjected to end cutting, and a cylindrical substrate having an outer diameter of 100 mm and a length of 360 mm as shown in Table 1 and a substrate N
o. 1 were used, and one was used for the measurement of the refractive index and the other was used for the preparation of the photoreceptor.

A coating solution composition for a conductive layer as described below was applied to each of the above-mentioned cylindrical substrates so as to have a dry film thickness of 0.5 μm, and heat-treated at 80 ° C. for 30 minutes.

2. Conductive layer coating solution composition Sumitomo Metal Mining Co., Ltd. conductive coating material X-101H 1000 g Toluene 1000 g On the above substrate, the coating solution composition UCL-2 of the intermediate layer (UCL) as described below has a dry film thickness of 1.0 μm. Was applied.

[0067] 3. UCL-2 coating solution composition Titanium chelate compound TC-750 (manufactured by Matsumoto Pharmaceutical Co., Ltd.) 200 g Silane coupling agent KBM-503 (manufactured by Shin-Etsu Chemical Co., Ltd.) 130 g 2-propanol 1000 g The coating liquid composition CGL-1 was applied so as to have a dry film thickness of 0.25 μm.

[0068] 4. CGL-1 coating solution composition Y-type titanyl phthalocyanine (CGM-1) 20 g Silicone resin (KR-5240 manufactured by Shin-Etsu Chemical Co., Ltd.) 40 g 2-butanone 1000 g (Dispersion of the above coating solution composition for 10 hours using a sand mill) ) A coating solution composition CTL-1 of a CTL layer as described below is applied on the CGL applied so as to have a dry film thickness of 25 μm, and heat-treated at 90 ° C. for 1 hour.
o. 1 was obtained.

[0069] 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

[0070]

Embedded image

Example 2 A substrate was prepared in the same manner as in Example 1 except that the rotation speed was set to 1000 RPM. The substrate was No.
2. No. 2 was obtained for the photosensitive drum. Let it be 2.

COMPARATIVE EXAMPLE Comparative Example As a photoreceptor substrate, prepolymerization conditions were 40 ° C. and 3 hours.
A substrate was prepared in the same manner as in Example 1 except that the number of revolutions and the number of revolutions were set to 2000 RPM. This comparative example substrate was designated No. S, the obtained photosensitive drum was No. S.

The substrate No. 1, No. 2 and No. The refractive index measurement (Abago refractometer manufactured by Atago Co.) was performed on the surface and inside of the drum of S, and the difference was determined. Table 1 shows the measurement results and appearance. If the number of rotations is too high, the non-uniformity seems to increase due to a difference in specific gravity.

[0074]

[Table 1]

1. Actual Photographic Test An electrophotographic internal exposure type image forming apparatus having the structure shown in FIG. 1, No. 2, N
o. S was mounted and 100,000 images were output. Table 2 shows the results. The resolution was evaluated from the number of distinguishable fine lines per 1 mm.

[0076]

[Table 2]

According to the present invention, when the difference in refractive index is kept within 0.1, a stable image free from blurring and distortion of the image can be obtained.

[0078]

According to the present invention, there is provided an electrophotograph having excellent characteristics that, when a photosensitive substrate is exposed to an image through the photosensitive substrate, there is no image blur, the image is not distorted, and the quality of the finished image is good. A translucent substrate for a photoreceptor, a method for producing the same, an electrophotographic photoreceptor using the same, an image forming method, and an image forming apparatus can be provided.

[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 sectional configuration diagram of the image forming apparatus of the present invention.

[Explanation of symbols]

Reference Signs List 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 developing device 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

Claims (10)

[Claims] 1. A translucent substrate for an electrophotographic photosensitive member,
The translucent substrate for an electrophotographic photosensitive member, wherein the translucent substrate is formed of a polymer resin, and the difference in the refractive index of the translucent substrate depending on the location is within 0.1. 2. The translucent substrate for an electrophotographic photoreceptor according to claim 1, wherein said polymer resin is a vinyl polymer resin. 3. The electrophotographic photosensitive member according to claim 1, wherein the polymer resin forming the light-transmitting substrate is synthesized from a crosslinkable monomer and a non-crosslinkable monomer. Transparent substrate for body. 4. The translucent substrate for an electrophotographic photosensitive member according to claim 1, wherein the polymer resin forming the translucent substrate is used by blending plural kinds of resins. 5. A method for producing a light-transmitting substrate for an electrophotographic photosensitive member, wherein the light-transmitting substrate is formed of a polymer resin, and a difference in refractive index between the light-transmitting substrates is within 0.1. A method for producing a light-transmitting substrate for an electrophotographic photosensitive member. 6. The method for producing a light-transmitting substrate for an electrophotographic photosensitive member according to claim 5, wherein the light-transmitting substrate is produced by a centrifugal polymerization method. 7. An electrophotographic photosensitive member comprising a light-transmitting substrate provided with a conductive layer and a photosensitive layer, wherein the light-transmitting substrate is formed of a polymer resin, and the difference in the refractive index of the light-transmitting substrate is zero. An electrophotographic photoreceptor characterized by being within 1. 8. The electrophotographic photoreceptor according to claim 7, wherein the photoreceptor is used for internal exposure for exposing through a light transmitting substrate. 9. A method for uniformly charging the surface of an electrophotographic photosensitive member, repeatedly performing image exposure and color development to form a multicolor superimposed image, and performing image transfer through batch transfer, separation, fixing, and photosensitive member cleaning steps. In the image forming apparatus to be formed, the electrophotographic photoreceptor uses a photoreceptor having a conductive layer and a photosensitive layer provided on a translucent substrate having a difference in refractive index within 0.1. An image forming apparatus, which forms an image by non-contact development by exposing the image to light passing through the image forming apparatus. 10. 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 the image forming method that goes through each step of cleaning, the electrophotographic photoreceptor is provided with a conductive layer and a photosensitive layer on a translucent substrate having a refractive index difference of 0.1 or less. An image forming method, wherein an image is exposed by passing through the translucent substrate using a photoreceptor, and image-forming by non-contact development.