JPH11288114A - 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 having good potential stability as the photoreceptor without deteriorating the electrophotographic performance and having high mechanical strength and stability without whitening the photoreceptor substrate even when it is repeatedly used and to provide the electrophotographic photoreceptor, an image forming method and an image forming device using this substrate. SOLUTION: This light-transmissive substrate consists of a polymer resin and the content of a low mol.wt. component having <500 mol.wt. in the polymer resin is controlled to 0.01 to 3.0 wt.%. This range is preferably 0.01 to 3.0 wt.% of the weight of the light-transmissive substrate and further, 0.02 to 2.0 wt.%. As a method for controlling the content to a proper range, in the case of a centrifugal polymn. method, conditions such as kinds of monomers to be polymerized, their combination and proportions, as well as kinds and amts. of crosslinking agents (hardening agents), heating schedule such as a temp. and a time at the time of the crosslinking, and temp. distribution in the system are controlled.

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 method, 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 formed 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. To smooth this series of movements and to efficiently use expensive members such as photoconductors,
In a practically used apparatus, a photosensitive drum having a photosensitive layer provided on a peripheral surface of a substantially cylindrical substrate is used as a photosensitive member. 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, but it is not easy to produce an electrostatic image forming member in a cylindrical shape with high accuracy 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 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.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a photosensitive member having a good electric potential stability without deteriorating electrophotographic performance. An object of the present invention is to provide a translucent substrate for an electrophotographic photosensitive member having high stability, a method for 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] An electrophotographic photosensitive material formed by a polymer resin, wherein the content of the low molecular weight component having a molecular weight of 500 or less in the polymer resin is 0.01 to 3.0% by weight. Transparent substrate for body.

[2] The translucent 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], which is a substrate for internal exposure.

[4] The translucent substrate is formed of a polymer resin, and the content of the low molecular weight component having a molecular weight of 500 or less in the polymer resin is set to 0.01 to 3.0% by weight. A method for producing a translucent substrate for an electrophotographic photosensitive member.

[5] The method for producing a translucent substrate for an electrophotographic photosensitive member according to [4], wherein the polymer resin is a vinyl polymer resin.

[6] The method for producing a light-transmitting substrate for an electrophotographic photosensitive member according to [4], wherein the light-transmitting substrate is prepared 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 has a molecular weight of 500 in the polymer resin.
An electrophotographic photosensitive member, wherein the content of the following low molecular weight components is 0.01 to 3.0% by weight.

[8] The electrophotographic photosensitive member according to [7], wherein the translucent substrate is a substrate for internal exposure.

[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 the image forming apparatus, the content of the low molecular weight component having a molecular weight of 500 or less in the polymer resin is 0.01 to 3.
Using an electrophotographic photoreceptor having a conductive layer and a photosensitive layer provided on a 0% translucent substrate, exposing the image through the translucent 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 including each step of body cleaning, a translucent substrate formed of a polymer resin and having a low molecular weight component having a molecular weight of 500 or less in the polymer resin in a content of 0.01 to 3.0%. An image forming method using an electrophotographic photoreceptor having a conductive layer and a photosensitive layer formed thereon, transmitting an image through a light-transmitting substrate, and forming an image by non-contact development.

As a result of intensive studies, the present inventors have found out the following. When preparing a translucent substrate by synthesizing a polymer resin from a monomer, unreacted monomers, a polymerization initiator, a cross-linking agent, or components stopped by an oligomer without being polymerized remain. Tends to. If these migrating low molecular weight components having a molecular weight of 500 or less are more than 3.0%, they migrate to the photosensitive layer during coating or storage, not only adversely affecting the potential characteristics, but also degrade the low molecular weight segregated in the substrate. The components cause optical distortion and clouding of the substrate. When such a substrate is used to form a large number of images and is used for a long period of time, poor transparency or optical distortion of the substrate may occur, and cracks or the like may occur due to an external impact.

On the other hand, if the content is less than 0.01%, there is no plasticizer in the substrate, so that the substrate becomes brittle, resulting in cracks, reduced strength against impact, and chipped edges. I do.

A preferable range is 0.01 to 3.0% by weight of the weight of the light-transmitting substrate, and more preferably 0.02 to 2.0% by weight.
0% by weight is good. As a method of controlling the content to an appropriate range, in the case of the centrifugal polymerization method, in addition to the type of the monomer to be polymerized and the conditions such as the combination method and the amount ratio, the type and amount of the crosslinking agent (curing agent), and the crosslinking. Adjusting the heating schedule such as the temperature and time at the time, the temperature distribution in the system, and the like.
When injection molding or extrusion molding is used, the resin to be used may be purified in advance by using a reprecipitation method, a heat treatment method, an ion exchange resin method or the like so as to have a specified impurity amount.

The low molecular weight component as used in the present invention means a component having a molecular weight of 500 or less.
100 g in tetrahydrofuran (THF) solvent for 8 hr
Can be determined by measuring the reflux liquid by liquid chromatography.

A typical method for producing a light-transmitting substrate for an electrophotographic photosensitive member according to the present invention will be specifically described by a centrifugal polymerization method using a vinyl polymer, 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 one of the mold holding members C3 in the direction of arrow B.

In the manufacturing process shown in FIG. 1, first, a vinyl polymerizable liquid material, for example, methyl methacrylate monomer is used, and a polymerization initiator is added in order to quickly polymerize the monomer and the viscosity is 10 cp or more and 400 cp or less. 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 cylindrical substrate obtained by such a manufacturing process has no internal distortion, a hardness comparable to aluminum, a light transmittance of 90% or more, and an impact resistance of about 15 times that of glass.

The non-vinyl resins constituting the base of the present invention include polyamide, polyimide, epoxy resin, polycarbonate, polysulfone, polyethersulfone, polyester, polyarylate, polyphenylene oxide, polybutylene terephthalate, polyethylene terephthalate, and the like. And polymethylpentene. These polymer 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, after dissolving in methylene chloride, a component having a molecular weight of 500 or less is 0.01 to
It is preferable to purify the solution by dropping it into a non-solvent such as acetone so as to have a concentration of 3.0% by weight, and then dry and then enter the above-mentioned molding step. As another method, a low-molecular component may be volatilized by treating with an ion exchange resin or heating a polymer. In general, injection molding and extrusion molding are manufactured under high temperature and high pressure. Therefore, some of the polymer may be thermally decomposed or hydrolyzed, or additives such as antioxidants and deterioration inhibitors may be decomposed. Refining and processing conditions, molding time, residence time, and the like are preferably determined.

A non-crosslinked vinyl polymer resin can also be used as a base material by the above method.

The centrifugal polymerization method preferably used in the present invention does not leave a die scratch on the surface of the cylindrical substrate, especially the inner surface is obtained by centrifugal force, as compared with the extrusion method which is a molding method widely used at present. It is formed into a natural surface and forms an extremely smooth inner surface such as a glass surface. In addition, it has excellent mechanical strength and thermal deformation temperature with no 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.

The preferred material for producing the substrate of the present invention is a monomer capable of radical polymerization (monomer, non-crosslinkable monomer) in the case of a vinyl polymer resin.
And, if necessary, polymerization or copolymerization using a polyfunctional vinyl compound (monomer having a cross-linking property) in the presence of a radical polymerization initiator. Crosslinking is preferred from the point of 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 , 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, and 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'-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, tri One or more selected from allyl isocyanurate, diallyl carbonate, diethylene glycol bisallyl carbonate and the like are used in combination as a crosslinking agent. The addition amount of the crosslinking agent is used in the range of 0.05 to 90% by weight based on the total amount of the raw material monomers (radical polymerizable monomer + polyfunctional vinyl compound). If the amount is less than 0.05% by weight, the heat resistance may not be satisfactory. If the amount is more than 90% by weight, the polymer becomes hard but brittle, so that the mechanical durability may be poor.

The radical polymerization initiator used in the polymerization of the synthetic resin for a substrate used in the present invention is not particularly limited, and is activated by an active energy ray such as visible light, infrared ray, ultraviolet ray, microwave, electron beam or heat. Any material that generates radicals may be used.

Radical polymerization initiators which 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 monomer, the polymerization curing temperature, and the like. In general, the mixing ratio is based on 100 parts by weight of the copolymerizable vinyl monomer. And preferably 0.01 to 8 parts by weight, particularly preferably 0.1 to 5 parts by weight. If the mixing ratio of the radical polymerization initiator is less than 0.01 part by weight, it 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 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 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 to provide the conductive layer and the 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, 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.

The binder resin usable for the charge generation layer includes, for example, polystyrene resin, polyethylene resin, polypropylene resin, polyacryl resin, polymethacryl resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinyl butyral resin, and poly (vinyl butyral). 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 the fatigue deterioration upon repeated use or to improve the 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.

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.

The substrate comprises a crosslinking agent for the electrostatic image forming body,
More favorable physical properties can be realized by mixing and using a conductivity-imparting agent, a coloring agent and the like with the polymerizable liquid material.

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.

Numeral 10 is a photoreceptor which is a drum-shaped electrostatic image forming member. 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 scorotron charging devices used in image forming processes of yellow (Y), magenta (M), cyan (C), and black (K). Perform a charging action by corona discharge to hold a charge of a predetermined potential,
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 above-described corona chargers 110Y, 110Y.
M, 110C and 110K charging, exposure optical system 1
The electrostatic latent image on the photoconductor 10 formed by the image exposure by 2Y, 12M, 12C and 12K is reversely developed in a non-contact state by applying a developing bias voltage.

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 10 is charged by 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), and the photosensitive drum 10 is rotated and scanned by the drum. An electrostatic latent image corresponding to the yellow (Y) image of the original image is formed on the photosensitive layer on the surface.

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

Next, the photosensitive drum 10 is further provided with a corona 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.

In this manner, 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 feed roller pairs 15b and 15c. The sheet is conveyed, and is transferred onto a transfer sheet P, which is a transfer material fed in synchronization with the toner image on the photoconductor 10, by driving the timing roller 16.

The transfer paper P to which the toner image has been transferred is separated from the drum peripheral surface by the removal of the charge in the charge eliminator 14b, and then is carried by the transport driving roller 14c and the driven roller 14d.
The fixing device 17 is moved by the conveying belt 14e stretched between the fixing belts.
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 photoreceptor 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 color has been described above, in the case of monochrome, contact development is preferably 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.

[0066]

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 Addition of a polymerization initiator azobisisobutyronitrile (AIBN) to methyl methacrylate monomer, 40 ° C., 1 hour
Preliminary polymerization by heating was performed to obtain a syrup-like polymerizable liquid material having a viscosity of about 100 cp.

The 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.
The polymerization was continued at a temperature / time schedule of 0 ° C. for 8 hours, 80 ° C. for 8 hours, and 100 ° C. for 20 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 cut at the end to obtain a cylindrical substrate having an outer diameter of 100 mm and a length of 360 mm. This was designated as Base No. Let it be 1. In addition, about 20 g of a section obtained at the time of the above-mentioned edge cutting processing was used as an analysis sample of the low molecular weight component of the substrate.

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, Inc.) 3 g Methanol / n-butanol = 10/1 (vol ratio) 1000 ml Coating solution composition for CGL layer as described below on UCL coated above CGL-1 was applied to a dry film thickness of 0.25 μm.

[0073] 4. CGL-1 coating liquid composition Y-type titanyl phthalocyanine (CGM-1) 20 g Silicone resin (KR-5240 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. ) A coating liquid composition CTL-1 of CTL is applied on the applied CGL so as to have a dry film thickness of 25 μm as follows,
A heat treatment at 90 ° C. for 1 hour was performed, and the photosensitive drum No. A
I got

[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]

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Comparative Example Comparative Example A centrifugal polymerization condition of the substrate of the photosensitive member was set to a polymerization temperature of 100.
The procedure was carried out in the same manner as in Example 1 except that the polymerization time was 8 ° C. This comparative example substrate was designated No. 1S, and the photosensitive drum is No. AS.

Example 2 (Examples and Comparative Examples) Preparation of Cylindrical Substrate A polymerization initiator, azobisisobutyronitrile (AIBN), was added to a monomer mixture of α-methylstyrene / methyl methacrylate / trimethylolpropane trimethacrylate (2/8/3 parts by weight). Preliminary polymerization was performed at 3 ° C. for 3 hours to obtain a syrup-like polymerizable liquid material having a viscosity of about 100 cp. This polymerizable liquid material has an inner diameter of 100 mm,
The mold is poured into a cylindrical mold having a length of 800 mm, and the whole mold is heated to 100 ° C. at a heating rate of 0.5 ° C./min while rotating the mold and intimately contacting the inner wall of the mold by centrifugal force. Was polymerized. 0.2 ° C.
After annealing at room temperature at a rate of / min, the mold was taken out of the mold.

The obtained substrate was subjected to end cutting processing to obtain a cylindrical substrate having an outer diameter of 100 mm and a length of 360 mm. This was designated as Base No. Let it be 2. In addition, about 25 g of a section obtained at the time of the above-mentioned edge cutting processing was used as an analysis sample of the low molecular weight component of the substrate.

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 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.

[0081] 3. UCL-2 coating solution composition Titanium chelate compound TC-750 (Matsumoto Pharmaceutical Co., Ltd.) 200 g Silane coupling agent KBM-503 (Shin-Etsu Chemical Co., Ltd.) 130 g 2-propanol 1000 g The coating liquid composition CGL-1 was applied to a dry film thickness of 0.25 μm.

[0082] 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 (The above coating solution composition is dispersed for 10 hours using a sand mill) A coating solution composition CTL-1 of a CTL layer as described below is applied to the applied CGL so as to have a dry film thickness of 25 μm, and is subjected to a heat treatment at 90 ° C. for 1 hour.
o. B was obtained.

[0083] 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 Comparative Example The heating rate was 0.1 ° C. as the condition for centrifugal polymerization of the photoconductor substrate. / Min, polymerization temperature 100 ° C, polymerization time 48h
A substrate was produced in the same manner as in Example 2 except that only r was used. The obtained substrate was dried with hot air at 80 ° C. for 1 hour, and the end cutting process of Example 2 was performed in the same manner. The subsequent coating process was the same as in Example 2. This comparative example substrate was designated No. 2S, the obtained photosensitive drum was designated No. BS.

The analysis results of each substrate are shown below.

Substrate Content (weight%) of molecular weight 500 or less Permeability (%) No. 1 0.1% 90% or more No. 1S 3.5% 80% 2 0.8% 90% or more 2S 0.008% 85% or more Actual Photographic Test An electrophotographic internal exposure type image forming apparatus having the structure shown in FIG. A, No. AS,
No. B, No. 100,000 images were output with the BS attached. In addition to the image, the drum edge, the internal transparency, cracks, resolution, etc. were observed. Table 1 shows the results.

Image Evaluation The samples on which images were obtained were visually observed for the last 1000 sheets.

Evaluation of Drum Damage After 100,000 sheets of images were output, the photosensitive drum was taken out of the apparatus and observed.

Evaluation of Resolution The resolution was evaluated based on the number of distinguishable thin lines per 1 mm.

[0089]

[Table 1]

Embodiment 3 1. Preparation of Cylindrical Substrate Bisphenol A type polycarbonate was synthesized according to a conventional method. After dissolving the obtained resin in methylene chloride, it was poured into an acetone solvent to precipitate and precipitate, and purified so that components having a molecular weight of 500 or less would be 0.5% by weight. This polycarbonate was pelletized and injection molded under the conditions of a cylinder temperature of 300 ° C., an injection pressure of 1100 kg / cm ² , and a mold temperature of 150 ° C., each having an inner diameter of 100 mm and a length of 800 m.
m was obtained. The resulting substrate was annealed to room temperature and then removed from the mold. The obtained substrate is subjected to edge cutting processing, further buffing, washing,
After drying, a cylindrical substrate having an outer diameter of 100 mm and a length of 360 mm was obtained. When a part of the substrate was taken out and quantified, components having a molecular weight of 500 or less increased to 2.0%. It is presumed that this was probably due to partial decomposition under high temperature and pressure during molding. This substrate is referred to as substrate N
o. 3 is assumed. A substrate without purification was used as a substrate of Comparative Example No. 3S. Molecular weight of this comparative substrate 500
The following components were 3.2% by weight.

The same conductive layer and intermediate layer as in Example 1 were applied on the cylindrical substrate, respectively, and the CGL layer was formed by the following CGL-
The CTL layer is coated with the following CGL-2 solution to a dry film thickness of 21 μm so that the two solutions have a dry film thickness of 0.5 μm.
The photosensitive drum No. C, Comparative Example Photoconductor No. CS was obtained.

CGL-2 coating liquid composition imidazole perylene (CGM-2) 250 g polyvinyl butyral (Eslec BXL Sekisui Chemical Co., Ltd.) 50 g 2-butanone 650 g cyclohexanone (The above coating liquid composition was dispersed using a sand mill for 20 hours. Thing) 150 g CTL-2 coating liquid composition CTM-2 80 g Polycarbonate (Z-200 manufactured by Mitsubishi Gas Chemical Company) 120 g 1,2-dichloroethane 1000 g

[0093]

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[0094]

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The actual photographing test, image evaluation and drum damage evaluation were performed in the same manner as in Examples 1 and 2, and the results shown in Table 2 were obtained.

[0096]

[Table 2]

It can be seen that the present invention has no problem in any of the characteristics.

According to the present invention, by controlling the content of the low molecular weight component having a molecular weight of 500 or less in the substrate to 0.01 to 3%, the electrophotographic performance due to the migration of the low molecular weight component, especially the fog in actual printing of a large number of sheets, is obtained. And no clouding of the substrate due to segregation of low molecular weight components. Also, it can be seen that there is no generation of optical distortion, brittleness, or cracking even under mechanical or thermal stress such as heat and pressure of the drum itself, and a stable image can be obtained.

[0099]

According to the present invention, the electrophotographic performance is not deteriorated and the potential stability as a photoreceptor is good.
A translucent substrate for an electrophotographic photoreceptor having high mechanical strength and stability without causing clouding of the photoreceptor substrate even when used repeatedly, a method of manufacturing 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 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 devices 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 polymer resin, wherein the content of a low molecular weight component having a molecular weight of 500 or less in the polymer resin is:
A translucent substrate for an electrophotographic photoreceptor, wherein the content is 0.01 to 3.0% by weight. 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, which is a substrate for internal exposure. 4. A transparent substrate formed of a polymer resin,
A method for producing a translucent substrate for an electrophotographic photosensitive member, wherein the content of a low molecular weight component having a molecular weight of 500 or less in the polymer resin is 0.01 to 3.0% by weight. 5. The method according to claim 4, wherein the polymer resin is a vinyl polymer resin. 6. The method for producing a light-transmitting substrate for an electrophotographic photosensitive member according to claim 4, wherein the light-transmitting substrate is prepared 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 polymer resin has a low molecular weight of 500 or less. An electrophotographic photoreceptor, wherein the content of the component is from 0.01 to 3.0% by weight. 8. The electrophotographic photosensitive member according to claim 7, wherein the light-transmitting substrate is a substrate for internal exposure. 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 resin is formed of a polymer resin, and has a molecular weight of 50 in the polymer resin.
An electrophotographic photosensitive member having a conductive layer and a photosensitive layer provided on a light-transmitting substrate having a low molecular weight component content of 0 or less of 0.01 to 3.0% is used to transmit light through the light-transmitting substrate. An image forming apparatus, wherein an image is exposed to light and an image is formed by non-contact development. 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 which goes through each step of cleaning, on a translucent substrate formed of a polymer resin, wherein the content of low molecular weight components having a molecular weight of 500 or less in the polymer resin is 0.01 to 3.0%. Using an electrophotographic photosensitive member provided with a conductive layer and a photosensitive layer, exposing the image to light through a translucent substrate, and forming an image by non-contact development.