JP2000039733A - Light-transmitting base body for electrophotographic photoreceptor, its production, electrophotographic photoreceptor using that, image forming method and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a light-transmitting base body which has high productivity, high dimensional accuracy and no water absorption or swelling in a high temp. and high humidity environment and which does not degrade electrophotographic performance by forming the body from a polymer resin and controlling the water absorption swelling rate to specified value or smaller, and to obtain a photoreceptor and an image forming device using this base body. SOLUTION: This light-transmitting base body is produced from a polymer resin and has <=200 μm water absorption swelling rate. The polymer resin is a vinyl polymer resin. The light-transmitting base body is suitable for an image forming device having the mechanism that an exposure device is disposed inside of a photoreceptor drum to expose the drum from the inside. For example, in a color image forming device, an org. photosensitive layer on a photoreceptor drum 10 is exposed from the inside of the base body through the transparent body by the exposure optical system 12Y, 12M, 12C, 12K. Therefore, exposure of the images corresponding to the second to fourth color signals can be carried out without influenced by the prior toner images, and electrostatic latent images having equal image quality to that of the image corresponding to the first color signal can be formed.

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 of manufacturing the same, and an electrophotographic photosensitive member and 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 which forms an image by an electrophotographic method, a toner image is formed on a rotating drum or a belt-shaped electrostatic image forming body (photoconductor) by performing charging, image exposure and development. Then, the toner image is transferred to a transfer material and then fixed.

[0003] In order to fulfill the function, the photoreceptor is placed at a distance from a charger, an exposure device, a developing device, a transfer device, a static eliminator, a cleaning device, or the like disposed around the photoreceptor.
It must be held at a predetermined timing and moved at a predetermined speed at a predetermined timing. 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 a material for 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.

[0005] On the other hand, plastic is considered to be a preferable material because of its light weight and low cost, but it is not easy to manufacture a photoreceptor in a cylindrical shape with high precision and industrially efficiently. The major factor is that a simple method of forming a cylindrical substrate having a required size and shape with high roundness 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. It also has the disadvantage that its water absorption expansion in a high-temperature and high-humidity environment is greater than that of a metal. There is also.

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 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 have not been put into practical use.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide high productivity, high dimensional accuracy, no water-swelling swelling in a high-temperature, high-humidity environment, and no deterioration in electrophotographic performance.
The potential stability of the photoconductor over time is good, and the mechanical strength and stability of the photoconductor substrate are high even when used repeatedly.
An object of the present invention is to provide a light-transmitting substrate for an electrophotographic photosensitive member, a method of manufacturing the same, an electrophotographic photosensitive member using the same, an image forming method, and an image forming apparatus.

[0008]

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

[1] A translucent substrate for an electrophotographic photosensitive member, which is formed of a polymer resin and has a water absorption swelling degree of 200 μm or less.

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

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

[4] The translucent substrate for an electrophotographic photosensitive member according to [1], wherein the water-absorbing swelling degree is 100 μm or less.

[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 the degree of water swelling is 200 μm or less.

[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] An electrophotographic photoreceptor 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 has a water-absorption swelling degree of 200 μm or less. Electrophotographic photoreceptor.

[8] The electrophotographic photosensitive member according to [7], which is for internal exposure.

[0017]

[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, a water absorption swelling degree formed of a polymer resin is 200 μm.
Using an electrophotographic photoreceptor having a conductive layer and a photosensitive layer provided on a light-transmitting substrate as described below, image-transmitting through the light-transmitting substrate, and forming an image by non-contact development. Image forming apparatus.

[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 an image forming method which passes through each step of body cleaning, an electrophotographic photosensitive member having a conductive layer and a photosensitive layer provided on a transparent substrate formed of a polymer resin and having a water absorption swelling degree of 200 μm or less is used. An image forming method, wherein an image is exposed through a light-sensitive substrate and an image is formed by non-contact development.

As a result of intensive studies, the present inventors have found out the following, and have accomplished the present invention.

When the degree of water absorption swelling of the resin substrate is larger than 200 μm, for example, the effect of water absorption in a high-temperature and high-humidity environment becomes evident in each characteristic, and it takes a long time for water to escape from the substrate. That is, local deformation of the resin base occurs, and it is difficult to return to the original state, and therefore, image writing becomes incomplete,
The image is blurred. In addition, the storage stability and durability of the resin substrate and the photoreceptor are deteriorated, and the potential stability and the image quality are adversely affected.

In the present invention, the degree of expansion of water absorption is more desirably 100 μm or less.

The degree of swelling of water was measured by placing the substrate in pure water at 20 ° C. for 6 hours.
It is determined from the difference between the outer diameter after flooding and the outer diameter after storage for 48 hours in an atmosphere of 20 ° C. and 30 RH%. In order to achieve the object of the present invention, the degree of water swelling of the resin substrate is set to 200.
μm or less. The reasons may be varied. Considering the developability and the resulting effect on image quality as one of the reasons, the fluctuation of the substrate outer diameter is
Since the distance between the developing sleeve and the photoreceptor also fluctuates, the developing property fluctuates, and when the degree of water swelling exceeds 200 μm, it is conceivable that the degree of adverse effect on the image quality becomes apparent.

The method for reducing the water absorption swelling of the resin substrate to 200 μm or less is not particularly limited, but selection of constituent materials such as a monomer to be polymerized and a crosslinking agent, polymerization conditions, crosslinking reaction conditions, humidity, This can be achieved by optimizing the production process such as the shape of the reactor and the post-treatment such as aging.

Next, a typical method for producing a light-transmitting substrate for an electrophotographic photosensitive member according to the present invention will be specifically described with reference to a centrifugal polymerization method using a vinyl monomer, as shown in FIG. 2 shows an example of a 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, one of the mold holding members C3
Is moved in the direction of arrow B to take out the cylindrical substrate.

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 to rapidly polymerize the monomer, and the viscosity is 10 cp to 400 cp. Adjust to a state and pour into cylindrical mold C1. This cylindrical mold usually has an inner diameter of 20 mm or more and 200 mm or less, and a length of 200 mm or more and 2000 mm or less. This is rotated together with the mold, and is heated appropriately to promote uniform polymerization. After the polymerization is completed, for example, an annealing treatment such as lowering the temperature very slowly is performed, and then the temperature is cooled to a temperature close to room temperature. The obtained substrate is removed from the mold, and cut and, if necessary, subjected to a finishing process for an electrophotographic photosensitive member. The translucent substrate is completed.

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. To form a smooth inner surface. Moreover, it has excellent mechanical strength and thermal deformation resistance without directionality, and it has less internal stress and less non-uniform light refraction when light is transmitted. Also, there is an advantage that the image exposure is not distorted and the image performance is not deteriorated.

As a preferable material for producing the substrate of the present invention, there is a polymer resin obtained from a vinyl monomer. In this case, a radical polymerization initiator (monomer, non-crosslinkable monomer) and, if necessary, a polyfunctional vinyl compound (crosslinkable monomer) are used to form a radical polymerization initiator. It can be obtained by polymerization or copolymerization in the presence. Crosslinking is preferred in terms of heat resistance, solvent resistance and dimensional stability.

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, 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 Acid, fumaric acid esters such as diisopropyl fumarate, dibenzyl fumarate, dicyclohexyl fumarate and the like, and other monomers include 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, and more preferably 40% by weight or more.

The polyfunctional vinyl compound (crosslinkable monomer) used in the present invention includes, for example, divinylbenzene,
Metadivinylbenzene, 4,4'-divinylbiphenyl, 3,3'-divinylbiphenyl, 3,4'-divinylbiphenyl, 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,
There are diethylene glycol bisallyl carbonate and the like, and if necessary, two or more kinds may be used in combination.

The amount of the crosslinking agent to be 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 may not be satisfactory. If it is more than 90% by weight, a hard but brittle polymer resin may be obtained, resulting in poor mechanical durability. Incidentally, a non-crosslinked vinyl polymer resin can also be used as the base material.

The radical polymerization initiator used in the polymerization of the resin for a substrate used in the present invention is not particularly limited, and active radicals such as visible rays, infrared rays, ultraviolet rays, microwaves, electron beams or the like, or active radicals may be used. What is necessary is just to generate | occur | produce.

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.

Acetophenone is used as a radical polymerization initiator for generating active radicals by activating energy rays.
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 polymerizable vinyl-based monomer. The content is 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 parts by weight, it may take a long time for the polymerization and curing, or the polymerization may not be completed. If the amount of the polymerization initiator exceeds 8 parts by weight, the polymer may become brittle or colored.

The non-vinyl resin constituting the base of the present invention includes polyamide, polyimide, epoxy resin, polycarbonate, polysulfone, polyethersulfone, polyester, polyarylate, polyphenylene oxide, polybutylene terephthalate, polyethylene terephthalate, and the like. And polymethylpentene. These polymer resin materials are subjected to a purification step to remove impurities, then pelletized, and injection-molded or extruded to produce the transparent cylindrical substrate of the present invention. For example, in the case of polycarbonate, since injection molding and extrusion molding are generally manufactured under high temperature and high pressure, a part of the resin is thermally decomposed or hydrolyzed, or additives such as an antioxidant and a deterioration inhibitor are decomposed. It is preferable to determine the refining and processing conditions, the molding time, the residence time, and the like in consideration of the minutes.

The translucency as referred to in the present invention means a material having a transmittance to exposure light of 50% or more, preferably 70% or more.
The light transmittance was measured using a Hitachi V-3500 spectrophotometer.
According to a measuring method using an integrating sphere specified in JIS K7105.

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 when a polymer of methyl methacrylate is used, and the transparency is extremely good and the strength is high. It is suitable for an image forming apparatus employing a mechanism for performing exposure from the inside.

A typical example 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.

An intermediate layer (undercoat layer) is provided below the charge generation layer for improving adhesion of the photosensitive layer, improving coatability, covering defects on the substrate, and improving charge injection from the substrate to the charge generation layer. You may. 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. A curable undercoat layer using an alkoxide, an organic metal chelate, or a silane coupling agent is used. These have a thickness of 0.01 to 5 μm.
It is applied so that it becomes about.

In the formation of the photosensitive layer, an inorganic photoconductor layer may be formed by vapor deposition or the like. However, an organic photoconductor layer, particularly 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, bisazo compounds, azo compounds such as 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, as a preferred binder when an imidazole perylene compound is used as CGM, a polyvinyl butyral resin is used. As a preferred binder when using TiOPc, a polysilicone resin and a polyvinyl butyral resin, or a mixture of both are used. No.

The charge transport layer (CTL) is composed of a charge transport material (CTM) alone or together with a binder resin. As the CTM, for example, 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, 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, and the like, 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 the durability, a non-photosensitive layer such as 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 diagram of a color image forming apparatus showing an example of an image forming apparatus to which the above-described electrophotographic photosensitive member made of the cylindrical substrate of the present invention is applied.

Reference numeral 10 denotes a photosensitive member which is a drum-shaped electrostatic image forming member. A transparent conductive layer and a charge generating layer are formed around 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 which use a non-contact developing method 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 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 temporarily 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 drive motor, and at the same time, the photosensitive member 1 is charged by the corona charging device 110Y.
Application of a potential to 0 starts.

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), and the exposure is performed by rotating the drum to scan. 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 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 static eliminator 14b, and thereafter, 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.
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.

Since the photosensitive drum 10 accommodates the exposure optical system therein, even if the diameter of the drum is relatively small, the plurality of corona charging devices 1 described above are provided on the outer peripheral surface thereof.
10Y, 110M, 110C and 110K, developing unit 1
3Y, 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 formation of the color superposed image has been described above, contact development may be performed in the case of a monochrome image.

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.

[0067]

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 The addition level of the polymerization initiator azobisisobutyronitrile (AIBN) and the crosslinking agent ethylene glycol dimethacrylate (EDMA) to the methyl methacrylate monomer was changed as shown in Table 1 to change the crosslinking level.

This was preliminarily polymerized at 30 ° C. for 1 hour to obtain a syrup polymerizable liquid material. This polymerizable liquid material is poured into a cylindrical mold having an inner diameter of 100 mm and a length of 800 mm. The mold is rotated and brought into close contact with the inner wall of the mold by centrifugal force.
The polymerization was continued at a temperature and time schedule of 100 ° C. for 8 hours. 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 edge cutting, and the outer diameter was 100 mm.
mm, an inner diameter of 96 mm and a length of 360 mm were obtained. These substrates were no. 1-1 to 1-3.

On the above-mentioned cylindrical substrate, a coating solution composition for a conductive layer as described below was applied so as to have a dry film thickness of 0.5 μm.
Heat treatment was performed at 0 ° C. for 30 minutes.

2. Conductive layer coating solution composition Conductive paint X-101H manufactured by Sumitomo Metal Mining Co., Ltd. 1000 g Toluene 1000 g The coating solution composition UCL-1 of the intermediate layer (UCL) is formed on the above substrate to a dry film thickness of 0.5 μm as follows. Was applied.

[0072] 3. UCL-1 coating solution composition Copolymer nylon resin (CM-8000, manufactured by Toray Industries) 30 g methanol / n-butanol = 10/1 (vol ratio) 1000 ml Coating solution composition of CGL layer on the applied UCL layer as follows The product CGL-1 was applied to a dry film thickness of 0.25 μm.

[0073] 4. CGL-1 coating liquid 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 (The above coating liquid composition is dispersed for 10 hours using a sand mill) The coating liquid composition CTL-1 of the CTL layer is applied on the CGL layer as described below so as to have a dry film thickness of 25 μm, and is heat-treated at 90 ° C. for 1 hour.
o. 1-1 to 1-3 were obtained.

[0074] 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

[0075]

Embedded image

Comparative Example The procedure of Example 1 was repeated except that no crosslinking agent was added. This comparative example substrate was designated No. 1S, and the photosensitive drum is No. 1S.

Example 2 (Examples and Comparative Examples) Preparation of cylindrical substrate α-methylstyrene / methyl methacrylate (weight ratio 2
/ 8), the amounts of the polymerization initiator azobisisobutyronitrile (AIBN) and the crosslinking agent divinylbenzene were changed as shown in Table 1, and prepolymerization was carried out at 50 ° C. for 3 hours to obtain a syrup-like polymerizable polymer. A liquid material was obtained. This polymerizable liquid material is poured into a cylindrical mold having an inner diameter of 100 mm and a length of 800 mm, and the mold is rotated and brought into close contact with the inner wall of the mold by centrifugal force, and the entire mold is heated at a heating rate of 0.5 ° C./mi.
n to 100 ° C., and polymerization was performed for 10 hours. 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 edge cutting to obtain a cylindrical substrate having an outer diameter of 100 mm, an inner diameter of 96 mm, and a length of 360 mm.

A coating solution composition for a conductive layer was applied on the cylindrical substrate as described below so as to have a dry film thickness of 0.5 μm.
Heat treatment was performed at 0 ° 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.

[0080] 3. UCL-2 coating liquid 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 CGL layer on the applied UCL layer as follows Was applied so as to have a dry film thickness of 0.25 μm.

4. CGL-1 coating liquid 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 (The above coating liquid composition is dispersed for 10 hours using a sand mill) The coating liquid composition CTL-1 of the CTL layer is applied on the CGL layer as described below so as to have a dry film thickness of 25 μm, and is heat-treated at 90 ° C. for 1 hour.
o. 2-1 to 2-3 were obtained.

[0082] 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 Comparative Example A coating was prepared in the same manner as in Example 2 except that no crosslinking agent was added. This comparative example substrate was No. 2S, and the photosensitive drum is No. 2S.

Performance Evaluation Measurement of the degree of water absorption and swelling Each substrate drum was placed in a thermostat at 20 ° C. and 30 RH% for 48 hours.
After storage, the outer diameter of each drum was measured and then completely immersed in pure water at 20 ° C. for 6 hours. After taking out from the pure water, the outer diameter was measured, and the outer diameter difference was determined. Further, the appearance of the drum and the light transmittance after water absorption and swelling were measured.

2. Actual Photographic Test An electrophotographic internal exposure type image forming apparatus having the structure shown in FIG. 1-1. 2
-3, No. 3; 1S, No. With 2S attached, 10,000 images were displayed under high temperature and high humidity (30 ° C., 80% RH).

Table 1 shows the results.

[0086]

[Table 1]

As in the present invention, no white turbidity occurs on the substrate.
It can be seen that the image characteristics are good and a stable image can be obtained from the initial stage up to 10,000 sheets even under high temperature and high humidity.

[0088]

Industrial Applicability According to the present invention, the productivity, the dimensional accuracy are high, the water absorption and expansion under high temperature and high humidity environment are not caused, the electrophotographic performance is not deteriorated, and the potential of the photoconductor over time is reduced. Transparent substrate for electrophotographic photoreceptor having high stability and high mechanical strength and stability of photoreceptor substrate even when used repeatedly, method for producing the same, electrophotographic photoreceptor using the same, image formation A 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 cross-sectional configuration diagram of the image forming apparatus of the present invention.

[Explanation of symbols]

Reference Signs List 10 photoconductor (photoconductor drum) 12Y, 12M yellow, magenta exposure optical system (exposure device) 12C, 12K cyan, black exposure optical system (exposure device) 13Y, 13M, 13C, 13K yellow, magenta, cyan, black Developing units 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

Continued on front page F term (reference) 2H030 BB02 BB23 2H035 CA07 CB02 2H068 AA21 AA54 AA58 BB08 BB10 BB57 EA04 FC06 2H077 AD06 DB12 DB13 DB15 EA15 EA16 GA13 GA17

Claims (10)

[Claims] 1. A translucent substrate for an electrophotographic photoreceptor, wherein the translucent substrate is made of a polymer resin and has a degree of water swelling of 200 μm or less. 2. The translucent substrate for an electrophotographic photosensitive member according to claim 1, wherein the polymer resin is a vinyl polymer resin. 3. The translucent substrate for an electrophotographic photosensitive member according to claim 1, wherein the polymer resin is a crosslinkable vinyl polymer resin. 4. The translucent substrate for an electrophotographic photoreceptor according to claim 1, wherein the water absorption swelling degree is 100 μm or less. 5. A light-transmitting substrate formed of a polymer resin,
A method for producing a translucent substrate for an electrophotographic photoreceptor, wherein the water absorption swelling degree is 200 μm or less. 6. The method for producing a translucent substrate for an electrophotographic photosensitive member according to claim 5, wherein the translucent substrate is produced by a centrifugal polymerization method. 7. An electrophotographic photoreceptor 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 has a degree of water swelling of 200 μm or less. Electrophotographic photoreceptor. 8. The electrophotographic photosensitive member according to claim 7, which is for internal exposure. 9. A method for uniformly charging the surface of an electrophotographic photosensitive member, repeating 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 an image forming apparatus to be formed, an electrophotographic photosensitive member having a conductive layer and a photosensitive layer provided on a light-transmitting substrate formed of a polymer resin and having a water absorption swelling degree of 200 μm or less is transmitted through the light-transmitting substrate. An image forming apparatus which forms an image by non-contact development. 10. A process for uniformly charging the surface of an electrophotographic photoreceptor, an image exposing step, and a color developing step to form a multicolor superimposed image, a batch transfer step, a separating step, a fixing step, and a photoreceptor. In an image forming method that passes through each step of cleaning, a light-transmitting material is used by using an electrophotographic photosensitive member in which a conductive layer and a photosensitive layer are provided on a light-transmitting substrate formed of a polymer resin and having a water absorption swelling degree of 200 μm or less. An image forming method, comprising exposing an image to light through a conductive substrate and forming an image by non-contact development.