Abstract: An image forming apparatus and a process for forming an image is provided whereby problems in an image such as interference fringes can be eliminated even at a higher resolution to improve image quality.

Abstract: Cylindrical base bodies for photosensitive drums according to first to fifth inventions are each formed by using a conductive resin composition containing a resin base material and a conductive agent dispersed in the resin base material. The base body of the first invention is characterized in that a dimensional accuracy is enhanced by using a mixture of a polyamide and a low water absorption resin as the conductive resin composition. The base body of the second invention is characterized in that a uniform and stable conductivity is obtained by using carbon black having a specific DBP oil absorption amount as the conductive agent. The base bodies of the third and fourth inventions are characterized in that a surface smoothness and a strength are enhanced by using a micro-spherical material or a flaked shape material, or a fibrous inorganic material having a specific fiber length and a specific fiber diameter as an inorganic filler for reinforcement added to the conductive resin composition.

Abstract: A process for producing an electrophotographic photosensitive member has at least one of the following steps a) and b) and the following steps c) and d) of; a) etching an aluminum substrate with at least one of an acid and an alkali; b) abrading an aluminum substrate with an abrasive dispersion containing 5% by volume or more of an abrasive having a 50% diameter of from 5 &mgr;m to 60 &mgr;m as measured in cumulative percentage; c) subjecting the aluminum substrate having been processed by at least one of the steps a) and b), to chemical conversion with an aqueous acid solution containing a salt of titanium or a salt of zirconium; and d) forming a photosensitive layer on the aluminum substrate having been subjected to the chemical conversion.

Abstract: A process for producing an electrophotographic photosensitive member has at least one of the following steps a) and b) and the following steps c) and d) of; a) etching an aluminum substrate with at least one of an acid and an alkali; b) abrading an aluminum substrate with an abrasive dispersion containing 5% by volume or more of an abrasive having a 50% diameter of from 5 &mgr;m to 60 &mgr;m as measured in cumulative percentage; c) subjecting the aluminum substrate having been processed by at least one of the steps a) and b), to chemical conversion with an aqueous acid solution containing a salt of titanium or a salt of zirconium; and d) forming a photosensitive layer on the aluminum substrate having been subjected to the chemical conversion.

Abstract: An electrophotographic photosensitive member is disclosed which has an aluminum substrate and a photosensitive layer. The substrate contains aluminum, oxygen and titanium, or aluminum, oxygen and zirconium, at the surface portion on the side of the photosensitive layer. Also, a process for producing the electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus using the photosensitive member are disclosed.

Abstract: The present invention provides an electrophotographic photosensitive member wherein a maximum height (RmaxD) of a surface roughness of a support portion is 1.2 &mgr;m≦RmaxD≦5.0 &mgr;m, an average roughness (Rz) of 10 points is 1.2 &mgr;m≦Rz≦3.0 m, an arithmetic average roughness (Ra) is 0.15 &mgr;m≦Ra≦0.5 &mgr;m, and an irregularity average interval (Sm) is 30 &mgr;m<Sm≦80 &mgr;m. The photosensitive member's charge generation layer contains a phthalocyanine compound, its charge transport layer has a thickness which is at least 9 &mgr;m but not larger than 18 &mgr;m, the electrophotographic photosensitive member in every 1 cm2 area has an electrostatic capacity (C) of 130 pF or more. This invention also provides a process cartridge and an electrophotographic apparatus containing the electrophotographic photosensitive member.

Abstract: Methods of forming a conductive aluminum substrate comprise anodizing a surface of an aluminum substrate to form a porous alumina surface layer, contacting the alumina surface layer with a liquid dispersion or solution of a polymer or at least one polymer-forming component, under conditions sufficient for the polymer to seal pores of the alumina surface layer, and removing excess polymer from the alumina surface layer. The resulting sealed conductive aluminum substrate is useful in photoconductors, for example of the dual layer type.

Abstract: An electrophotographic photoreceptor is disclosed. The photoreceptor has a photosensitive layer provided on an electrically conductive support which has a sealed alumite film, a surface layer of said electrophotographic photoreceptor comprises a hardenable siloxane resin having charge transportability or a hardenable siloxane resin comprising a partial structure having charge transportability.

Abstract: An electrophotographic photoreceptor having an interlayer between the electrically conductive base body and the photosensitive layer. The electrophotographic photoreceptor an aluminum-evaporated surface and contact potential difference of said interlayer with respect to the aluminum-evaporated surface of the photoreceptor is at least +0.175 V.

Abstract: An electrophotographic photosensitive member is comprised of a support and a charge generation layer and a charge transport layer provided on the support in this order.

Abstract: A resin made base body for a photosensitive drum is characterized in that (1) a large number of irregularities composed of microscopic stripe-shaped projections and depressions extending in the axial direction of the base body composed of a synthetic resin made pipe are formed on an outer peripheral surface of the pipe; (2) a large number of irregularities composed of microscopic stripe-shaped projections and depressions extending in the circumferential direction of the base body composed of a synthetic resin made pipe are formed on an outer peripheral surface of the pipe; (3) a specular gloss at 60° of a surface of the base body composed of a synthetic resin made pipe, specified under JIS Z8741, is set in a range of 12 to 30; and (4) a skin layer having a high resistance is formed in an outer peripheral portion in the thickness direction of a peripheral wall of the base body composed of a synthetic resin made pipe, wherein an amount of the conductive agent present in the skin layer is equal to or less th

Abstract: A process including providing at least a flexible substrate layer having a first major surface on one side and a second major surface on a second side opposite the first major surface, the first major surface being an exposed surface, applying a coating of an anticurl backing layer dispersion on the first major surface of the substrate layer, the dispersion comprising a volatile carrier liquid, a film forming polymer dissolved in the volatile carrier liquid, solid organic particles dispersed in the volatile carrier liquid, and an organic additive dissolved in the volatile carrier liquid, the organic additive represented by the structural formula: wherein m is a number from 1 to 99, n is a number from 1 to 99, p is an integer between 1 and 10, f is an integer between 1 and 8, and I is an integer between 10 and 500, and drying the coating to remove the volatile carrier and form a dried anticurl backing layer.

Abstract: There is provided an electrophotographic method, in which influence on an image quality attributable to the conditions of the photoreceptor surface is reduced and much sharper and high image quality having high resolution is obtained, when a spot size of the exposure light is made finer as progress is made in high resolution. In a digital exposure system electrophotographic method of a BAE system which performs scan-exposing for an image formation on a photoreceptor, a photoreceptor comprising a supporting member 401 comprising aluminum or an aluminum alloy and a photosensitive layer 402 deposited on the supporting member surface by applying surface treatment using water on its surface, on which a convex structure is formed corresponding to a boundary portion of a crystal grain boundary of the supporting member surface is used.

Abstract: A spherical silicone additive is selected and introduced into a contact region between a photoreceptor's anti-curl layer and an electrophotographic system's backer bar, and into a bulk material of the electrophotographic system's spots blade. The additive reduces frictional drag and wear at the contact region between the anti-curl layer and the backer bar and at a contact region between a photoreceptor's outermost surface and the system's spots blade. The reduction of photoreceptor drag and wear at the above contact regions reduces photoreceptor surface irregularities, excessive backer bar wear, excessive spots blade wear, belt ripple and belt contamination. As a result, system drive torque requirements may be minimized, the life of the contacting system components may be extended and system performance may be improved.

Abstract: Disclosed herein are a mixed resin compound, a resin pipe, a process for producing said resin pipe, and a photosensitive drum. The resin compound meets at least one of the following requirements. It is a mixture of two or more kinds of resins blended in a specific manner, it undergoes annealing under specific conditions, and it has specific values of surface roughness, Vickers hardness, coefficient of linear expansion, flexural modulus, and thermal conductivity. The resin pipe is suitable for use as the cylindrical base of the photosensitive drum for electrophotographic machines, such as copying machines, facsimiles, and printers. It is superior in surface smoothness, dimensional stability, coatability, and handlability, and hence it is very little vulnerable to damage during handling and dimensional change due to resin shrinkage and is; superior in heat resistance (desirable for solvent removal) and mechanical strength (desirable for flange fitting).

Abstract: An organic photoconductor is disclosed, which comprises a cylindrical electrically conductive support and, formed thereon in this order, a charge-generating layer and a charge-transporting layer, the external surface of the cylindrical electrically conductive support having an index of surface area as defined by the following equation (I) of from 0.01 to 0.10, and the charge-generating layer having a multilayer structure comprising a charge-generating layer having n-type semiconductor characteristics and a charge-generating layer having p-type semiconductor characteristics: (Sa/Sm)−1  (I) wherein Sa is the actual surface area of the external surface of the cylindrical electrically conductive support and Sm is the theoretical surface area thereof calculated on the assumption that the support is an ideal cylinder.

Abstract: A photoreceptor including a support and a photosensitive layer formed thereon, optionally an undercoat layer between the support and the photosensitive layer, wherein when a group of data consisting of N samples of the height x(t)(&mgr;m) of a profile at the interface of the support on the side of the photosensitive layer, the interface of the photosensitive layer on the side of the support, and/or the interface of the undercoat layer on the side of the photosensitive layer, measured perpendicular to a horizontal direction of the support, taken at &Dgr;t (&mgr;m) intervals in the horizontal direction, is subjected to Fourier transformation in accordance with a formula as specified in the specification, in a power spectrum obtained by the Fourier transformation, I(S) represented by a formula specified in the specification has a particular value, a method of evaluating the above photoreceptor, a method of producing the photoreceptor, and an image formation apparatus in which the photoreceptor is incorporated ar

Abstract: An electrophotography photoconductor has a conductive substrate and an anodic oxidation layer on which a photoconductive layer is formed. The sealed surface of the anodic oxidation has an admittance ranging from 0.4 S/m2 to 30 S/m2 and a contact angle of pure water ranging 30° to 80°. The surface of the anodic oxidation layer is sealed by dipping it into a nickel acetate solution. The contact angle and the admittance are determined depending on a temperature of the nickel acetate solution and a sealing time. In the case where the sealed surface is irradiated with ultraviolet rays, the heat-resisting property and cleanliness are improved.

Abstract: This invention relates to laminates in which a layer of polyimide precursors and a layer of photosensitive resins are formed one on top of another on an electric conductor such as a stainless steel foil and also to laminates consisting of a stainless steel foil and successive layers of polyimide precursors and photosensitive resins useful for the manufacture of HDD suspensions. In particular, the use of resins containing a repeating unit derivable from specific aromatic diamines and aromatic carboxylic acid dianhydrides as polyimide precursors makes it possible to fabricate an insulator of high fabrication accuracy and reliability on an electric conductor and, in addition, the laminates are useful as materials for the manufacture of HDD suspensions of an integrated circuit/wiring structure with high accuracy.

Abstract: An electrostatographic imaging member including: a flexible supporting substrate; an imaging layer having an optional adjacent ground strip layer coated on one side of the substrate; and an anti-curl backing layer coated on the other side of the substrate which layer is comprised of a film forming polymer binder, an optional adhesion promoting polymer, and a dispersion of polytetrafluoroethylene particles which dispersion has particles with a narrow diameter particle size distribution of from about 0.19 micrometer to about 0.21 micrometer, and an average diameter particle size of about 0.20 micrometer. The optional ground strip layer can include the same dispersion of polytetrafluoroethylene particles as the anti-curl backing layer.

Abstract: A lithographic printing plate having an average curvature in a rolling direction of 1.5×10−3 mm−1 or less, a curvature distribution in a crosswise direction of 1.5×10−3 mm−1 or less, and a curvature in a direction perpendicular to said rolling direction of 1.0×10−3 mm−1 or less and a method for producing the printing plate are disclosed. A method for producing a support for a lithographic printing plate is also disclosed, which comprises roughening a surface of an aluminum web having a center line average surface roughness of 0.15 to 0.35 &mgr;m and a maximum surface roughness of 1 to 3.5 &mgr;m by at least one of mechanical surface roughening, chemical etching and electrochemical surface roughening, and then applying anodization thereto.

Abstract: A sound deadening member for electrophotographic photoreceptor composed of a molded thermoplastic resin composition obtained by compounding at least 10 parts by weight of a copolymer (A) having a glass transition point of at least 40° C. and being made of from 10 to 90% by weight (meth)acrylic acid ester monomer(s) and not more than 90 parts by weight of a styrene-base resin (B) such that the sum total becomes 100 parts by weight and an electrophotographic photoreceptor having the sound deadening member for electrophotographic photoreceptor in the inside of the conductive substrate.

Abstract: A process for forming an abrasion-resistant antistatic layer for an imaging element comprises: adjusting the pH of an aqueous composition of an electronically-conductive polymer to a pH of about 3 to about 10, and combining the pH-adjusted aqueous composition of the electronically-conductive polymer with an aqueous composition at a pH greater than 7 of a polyurethane film-forming binder having a tensile elongation to break of at least 50% and a Young's modulus measured at 2% elongation of at least 50000 psi. The process further comprises applying the resulting coating composition to the imaging element, thereby forming an abrasion-resistant antistatic layer on the element. The antistatic layer coating composition of the present invention can be applied to a wide variety of imaging elements, including, for example, photographic, electrostatographic, photothermographic, migration, electrothermographic, dielectric recording and thermal-dye-transfer imaging elements.

Abstract: Multiple-seam electrostatographic imaging member belts include two or more imaging member portions joined together by two or more seams. The belts can be formed from imaging member web that either includes or does not include an anti-curl backing layer, and that includes a charge transport layer that is substantially stress free.

Abstract: An electrophotographic method which uses a single-layer organic photosensitive material drum having a single organic photosensitive layer of a thickness of not smaller than 25 &mgr;m formed on an electrically conducting blank tube with a surface roughness Ra of not larger than 0.6 &mgr;m and rotates the photosensitive material drum at a peripheral speed of not smaller than 400 mm/sec, in order to execute an image-forming processing that includes electric charging, exposure to image-bearing light, developing, transfer, cleaning by a blade and removal of electric charge. Though the photosensitive material drum rotates at a high speed and a large frictional force is exerted on the cleaning blade, damage to the blade is effectively suppressed, and image is stably formed for extended periods of time without permitting the cleaning to become defective.

Abstract: A flexible electrostatographic imaging member including at least one photographic imaging layer, a support layer, and an anticurl back layer having an exposed surface including a cross linked phenoxy resin at the exposed surface, the phenoxy resin being formed from a solution including cross linkable solvent soluble phenoxy resin containing hydroxyl groups attached to carbon atoms, an acid having a pKa less than about 3, a cross linking agent selected from the group including a formaldehyde generating cross linking agent, an alkoxylated cross linking agent, a methylolamine cross linking agent and mixtures thereof, and a liquid selected from the group including solvents, diluent and mixtures thereof.

Abstract: A photosensitive body for electrophotographical use has a conductive base body and a marking area provided thereon. The maximum surface roughness of a photosensitive layer provided right on the marking area is specified not to exceed 2.5 &mgr;m. And also, a ratio of the optical reflective index of the marking area to the optical reflective index of the non-marking area is specified to be in a range of 0.3 to 0.7. In this manner, even when the photosensitive layer is thin (not exceeding 25 &mgr;m), it is possible to prevent problems such as inadequate cleaning and toner falling. Hence, it is possible to offer a photosensitive body for electrophotographical use which can constantly produce high quality copied images.

Abstract: An electrophotographic photosensitive member is comprised of an aluminum substrate and a photosensitive layer provided thereon. The surface substrate on the side of the photosensitive member contains the elements aluminum, oxygen and titanium, or the elements aluminum, oxygen and zirconium. The photosensitive layer contains chlorogallium phthalocyanine, hydroxygallium phthalocyanine or oxytitanium phthalocyanine. The oxytitanium phthalocyanine has an intense peak at each of the Bragg's angles (2&thgr;G+0.2°) shown in any one of the specific five groups in CuK&agr;-characteristic X-ray diffraction.

Abstract: A lithographic printing plate having an average curvature in a rolling direction of 1.5×10−3 mm−1 or less, a curvature distribution in a crosswise direction of 1.5×10−3 mm−1 or less, and a curvature in a direction perpendicular to said rolling direction of 1.0×10−3 mm−1 or less and a method for producing the printing plate are disclosed. A method for producing a support for a lithographic printing plate is also disclosed, which comprises roughening a surface of an aluminum web having a center line average surface roughness of 0.15 to 0.35 &mgr;m and a maximum surface roughness of 1 to 3.5 &mgr;m by at least one of mechanical surface roughening, chemical etching and electrochemical surface roughening, and then applying anodization thereto.

Abstract: The invention relates to a photosensitive drum based on a cylindrical base which is made with an electrically conductive resin composition which comprises a polyamide resin as the resin component and an electrically conductive material, said polyamide resin being one selected from the group consisting of polyamide resins obtained from m-xylylenediamine and adipic acid, polyamide resins obtained from &egr;-caprolactam, and mixtures thereof. The cylindrical base for the photosensitive drum has good surface smoothness as well as good mechanical strength, and it can be obtained easily by injection molding or the like from said resin composition.

Abstract: A process for producing a lithographic printing plate which is inexpensive, is not elongated, can be readily handled and can provide a uniform image, is disclosed. The process comprises the steps of: using an original plate for lithographic printing comprising a support having a volume electric resistance of more than 1×1010 &OHgr;·cm, a conductive layer having a volume electric resistance of 1×105 &OHgr;·cm or less, provided on one surface of the support, and a photoconductive layer containing zinc oxide and a binder, provided on the conductive layer, conducting negative corona discharge from the side of the photoconductive layer of the original plate for lithographic printing, and during this corona discharge, contacting a conductor having earth potential with at least the support of the original plate, thereby charging the photoconductive layer of the original plate for lithographic printing.

Abstract: A flexible electrostatographic imaging member including at least one photographic imaging layer, a support layer, and an anticurl back layer having an exposed surface including a cross linked polyamide at the exposed surface, the polyamide being, formed from a solution selected from the group including a first solution including crosslinkable alcohol soluble polyamide containing methoxy methyl groups attached to amide nitrogen atoms, an acid having a pKa less than about 3, a cross linking agent selected from the group including a formaldehyde generating cross linking agent, an alkoxylated cross linking agent, a methylolamine cross linking agent and mixtures thereof, and a liquid selected from the group including alcohol solvents, diluent and mixtures thereof, a second solution including crosslinkable alcohol soluble polyamide free of methoxy methyl groups attached to amide nitrogen atoms, an acid having a pKa less than about 3, a cross linking agent selected from the group including a an alkoxyla

Abstract: An image forming apparatus using an electrophotographic processor with a transfer roller, a charge roller and a photosensitive drum for image formation. The photosensitive drum is comprised of a cylindrical elastic body exhibiting a predetermined level of elasticity; a conductive film formed on an outer surface of said cylindrical elastic body; an image carrier generation layer of a first photoconductive material formed on the conductive film; and an image carrier transfer layer of a second photoconductive material formed on said image carrier generation layer.

Abstract: A transparent substrate for the electrophotographic photoreceptor is disclosed. The substrate is cylindrical and made of a polymer resin, and Rz of an inner surface of the cylindrical substrate is not more than 0.5 .mu.m. The electrophotographic photoreceptor employing the substrate is suitably used for imagewise exposure of the electrophotographic photoreceptor from the inside of the cylindrical substrate. An image forming method employing the photoreceptor is also disclosed.

Abstract: A polycarbonate containing repeating units (1) represented by the general formula (1), a polycarbonate molding produced by molding the polycarbonate, and an electrophotographic photoreceptor having a photosensitive layer which has a surface layer containing the polycarbonate: ##STR1## wherein R is an aliphatic unsaturation-free monovalent hydrocarbon group, R.sup.1 is a halogen atom, an alkyl group, an alkoxy group or an aryl group, X is an alkylene group or an alkyleneoxyalkylene group, X' is an alkylene group of 2 or more carbon atoms, an alkyleneoxyalkylene group or oxygen atom, a is an integer of 0 to 4, na is 0 or 1, nb is 1 or 2, nc is 1 or 2, provided na+nb+nc=3, n1, n2, n3 and n4 are 0 or an integer of 1 or more, provided n1+n2+n3+n4 is an integer of 0 to 450.

Abstract: An electrophotographic photosensitive member is provided which does not involve any image noise occurrence, such as black spot or white spot under any environment. The electrophotographic photosensitive member comprises a photoreceptor substrate including an anodized layer formed on the surface of an aluminum or aluminum alloy base, the anodized layer having been sealed by a low temperature sealing treatment and a high temperature sealing treatment, and at least one photosensitive layer formed on the photoreceptor substrate.

Abstract: A cylindrical, photosensitive member is disclosed which has a photosensitive layer comprising amorphous silicon provided on an electroconductive substrate, and in which the thickness of the electroconductive substrate is not less than 0.1 mm but less than 2.5 mm, thereby accomplishing cost reduction of the photosensitive member and also accomplishing prevention of variations of image density and image smearing by high-accuracy temperature control.

Abstract: An imaging member including: (a) a substrate layer; (b) an imaging layer; and (c) an abrasion resistant layer selected from the group consisting of an overcoating layer and an anti-curl layer, wherein the abrasion resistant layer includes a branched polycarbonate.

Abstract: An electrostatographic imaging member including an anti-curl layer, a supporting substrate having an electrically conductive layer, at least one imaging layer, an optional ground strip layer and an optional overcoating layer, the anti-curl layer including a polycarbonate film forming polymer binder containing 3,3,5-trimethylcyclohexane groups in the polycarbonate moiety.

Abstract: A photoreceptor for forming an electrophotography is disclosed. The photoreceptor comprises a photosensitive layer in an area excluding both edges in the axial direction on a cylindrical aluminum support and silicon oil on the surface of both edges which have no photosensitive layer on the cylindrical aluminum support.

Abstract: An electrophotography photoconductor has a conductive substrate and an anodic oxidation layer on which a photoconductive layer is formed. The sealed surface of the anodic oxidation has an admittance ranging from 0.4 S/m.sup.2 to 30 S/m.sup.2 and a contact angle of pure water ranging 30.degree. to 80.degree.. The surface of the anodic oxidation layer is sealed by dipping it into a nickel acetate solution. The contact angle and the admittance are determined depending on a temperature of the nickel acetate solution and a sealing time. In the case where the sealed surface is irradiated with ultraviolet rays, the heat-resisting property and cleanliness are improved.

Abstract: There is disclosed a process for forming a photosensitive imaging member including positioning a substrate and an electrode in an electrolytic solution to form a galvanic cell and electrochemically graining the substrate surface in the absence of an external power source to provide a substrate surface roughness sufficient to substantially suppress the formation of a pattern of light and dark interference fringes upon exposure of the photosensitive imaging member to a light source.

Abstract: An electrophotographic photoreceptor and a cleaning method of the support therefor are disclosed. The element of Si and Na remaining on the support surface, evaluated in terms of ESCA, has the following relation with a major element constituting the support;0<[Si(surf)/Xs-Si(bulk)/Xb].ltoreq.0.50<[Na(surf)/Xs-Na(bulk)/Xb].ltoreq.0.3,whereinSi(surf): ESCA measurement (silicon) of a support surface after cleaningNa(surf): ESCA measurement (sodium) of a support surface after cleaningSi(bulk): ESCA measurement (silicon) of a support bulkNa(bulk): ESCA measurement (sodium) of a support bulkXs: ESCA measurement (support surface after cleaning) of a major element constituting a supportXb: ESCA measurement (support bulk) of a major element constituting a support.

Abstract: A developer carrying member is comprised of a substrate and a coat layer which covers the surface of the substrate. The coat layer contains at least a binder resin, conductive spherical particles having a number average particle diameter of from 0.3 .mu.m to 30 .mu.m and a true density of 3 g/cm.sup.3 or below, and a nitrogen-containing heterocyclic compound, the particles and the compound being dispersed in the binder resin.

Abstract: Electrophotographic printing apparatus is described, particularly useful for printing a plurality of copies from a single latent electrostatic image, in which the toner transfer system includes a multi-layer transfer photoreceptor having an outer dielectric layer, an inner electrically-conductive layer, and an intermediate photoconductive layer forming an interface with the outer dielectric layer. A charging system charges the outer surface of the outer dielectric layer of the transfer photoreceptor with charges of one polarity to facilitate the transfer of the toner image from the recording photoreceptor to the record member, and produces in the interface, between the photoconductive layer and the outer dielectric layer, charges of the opposite polarity to maintain the charges of said one polarity on the outer surface of the transfer photoreceptor. The transfer photoreceptor may also serve to transport the record member and to separate the record member from the recording photoreceptor.

Abstract: An electrophotographic photoconductor drum having a cylindrical hollow support with a length L (cm), provided that L is 30 cm or more, a photoconductive layer provided on an external surface of the cylindrical hollow support, with a total weight of the support and the photoconductive layer being W1 (g), and a weight-controlling member, with a total weight of the above-mentioned weight W1 (g) and the weight-controlling member being W2 (g), the length L, the weight W1 and the weight W2 satisfying the relationship of formula (1) of log(W1/L.sup.3).ltoreq.-2.4 and the formula (2) of log(W2/L.sup.3)>-2.4.

Abstract: An electrophotographic photoconductor has an electroconductive support, and a photoconductive layer which is formed thereon and contains as an effective component an aromatic polycarbonate resin having a structural unit of formula (1), two structural units of formula (1) and (2), or a repeat unit of formula (3): ##STR1## wherein R.sup.1 and R.sup.z Ar.sup.1 to Ar.sup.6, X, Y, s and n are as specified in the specification. The above-mentioned aromatic polycarbonate resin is provided with charge transporting properties.

Abstract: Cylindrical tubular substrates for an electrophotographic conductor can be made with different lengths from an injection-molded plastic cylindrical mother tube. The length of the mother tube is sufficient for the greatest desired length. The mother tube has a slanting inner surface which facilitates removal of the tube from the molding die, and non-slanting inner end surfaces which can be stepped. The desired length is obtained by cutting the mother tube across one of the steps. The resulting non-slanting inner end surface of the substrate provides a spigot joint for tightly receiving a flange.

Abstract: An electrophotographic apparatus in which image formation is carried out by repeating charging, dot exposure, development, transfer, separation, and cleaning wherein the electrophotographic apparatus employs a photoreceptor composed of a support having thereon a photosensitive layer, and in which the machined circumferential surface, which is regularly formed in the direction along with the center axis of cylindrical support, satisfies Formula 1 below.L/A=n+(0.35 to 0.65) Formula 1whereinL: machined cycle width (.mu.m)A: recording dot pitchn: integer of 0 or moreThe electrophotographic apparatus is obtained which causes neither interference fringes or streaking due to the unevenness of the coating layer and the machined substrate surface.

Abstract: A photoreceptor drum having flanges at the ends of a cylindrical substrate is disclosed. The flange contains a heat-resistant thermoplastic resin and a compound comprising a metal selected from a group consisting of Sb, Sn, Pb, Ge, Ga and Zn.