G03G5/14708

IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD
20200292954 · 2020-09-17 ·

An image forming apparatus including developing unit to develop electrostatic latent image with toner to form visible image, and cleaning unit including elastic member including surface layer and configured to remove the toner, wherein Martens hardness A and Martens hardness B of the surface layer measured by applying load of 1 N and load of 1,000 N, respectively, to position of the surface layer in thickness direction thereof using nanoindenter are both 2.5 N/mm.sup.2 or greater but 32.5 N/mm.sup.2 or less, and Martens hardness A and Martens hardness B satisfy inequality,


Martens hardness A>Martens hardness B

wherein coefficient of dynamic friction of the surface layer against polycarbonate is 0.5 or less, and the toner includes polyester resin insoluble to THF and Tg of THF-insoluble component of the toner determined from DSC curve of first heating of DSC is 60 C. or higher but 20 C. or lower.

Electrophotographic photosensitive member, production method therefor, process cartridge, and electrophotographic image-forming apparatus

Provided is an electrophotographic photosensitive member that suppresses image smearing at the time of its repeated use, and expresses satisfactory wear resistance and electric characteristics. The electrophotographic photosensitive member includes a support and a photosensitive layer in the stated order, wherein a surface layer of the electrophotographic photosensitive member contains a copolymer of a hole-transportable compound having a chain-polymerizable functional group and a specific compound having maleimide groups.

ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC APPARATUS
20200272065 · 2020-08-27 ·

An electrophotographic photoreceptor includes a support, a photosensitive layer, and a protection layer. The protection layer contains a copolymer of a compound having a specific frame and a hole-transporting compound containing a specific polarizable functional group.

ELECTROPHOTOGRAPHIC PHOTORECEPTOR AND IMAGE FORMING APPARATUS
20200257211 · 2020-08-13 · ·

An electrophotographic photoreceptor includes a cylindrical substrate; and a surface layer located on an outer surface of the cylindrical substrate. At least a substrate central portion in a cylindrical axial direction of the outer surface of the cylindrical substrate is formed as a rough surface, and a surface roughness of a surface-layer central portion in the cylindrical axial direction of an outer surface of the surface layer is larger than that of at least one of two surface-layer end portions in the cylindrical axial direction of the outer surface of the surface layer. An image forming apparatus includes the electrophotographic photoreceptor; and a peripheral member capable of contacting a surface of the electrophotographic photoreceptor.

Organic photoconductor drum having an overcoat containing nano metal oxide particles and method to make the same

An improved organic photoconductor drum having a protective overcoat layer and method to make the same is provided. The protective overcoat layer is prepared from a curable composition including nano metal oxide particles sized less than 400 nm in combination with an urethane acrylate resin having at least 6 functional groups.

Organic photoconductor drum having an overcoat containing nano metal oxide particles and method to make the same

An improved organic photoconductor drum having a protective overcoat layer and method to make the same is provided. The protective overcoat layer is prepared from a curable composition including nano metal oxide particles sized less than 400 nm in combination with an urethane acrylate resin having at least 6 functional groups.

Electrophotographic photoreceptor, and electrophotographic image forming method and electrophotographic image forming apparatus using the same

An electrophotographic photoreceptor includes an outermost layer formed of a polymerized cured product of a composition containing a polymerizable monomer and metal oxide particles surface-treated with a surface treatment agent having a silicone chain, wherein a ratio (r/r) between a number average primary particle diameter (r) of metal oxide particles which are untreated base particles of the metal oxide particles surface-treated with the surface treatment agent having a silicone chain and a sphere equivalent particle diameter (r) of the untreated base particles calculated from a specific surface area measured by a nitrogen adsorption method is 1.5 or more and 6.0 or less, and a surface treatment amount with the surface treatment agent having a silicone chain per surface area of the untreated base particles is 0.0005 g/m.sup.2 or more and 0.0015 g/m.sup.2 or less.

Photosensitive body including protective layer formed on photosensitive layer

A photosensitive body is provided. The photosensitive body includes a photosensitive layer, and a protective layer formed on the photosensitive layer, and the protective layer includes a urethane oligomer acrylate and a modified perfluoropolyether acrylate.

ELECTROPHOTOGRAPHIC PHOTORECEPTOR AND IMAGE FORMING APPARATUS
20200081359 · 2020-03-12 · ·

An electrophotographic photoreceptor includes a cylindrical substrate; and a surface layer located on an outer surface of the cylindrical substrate. At least a substrate central portion in a cylindrical axial direction of the outer surface of the cylindrical substrate is formed as a rough surface, and a surface roughness of a surface-layer central portion in the cylindrical axial direction of an outer surface of the surface layer is larger than that of at least one of two surface-layer end portions in the cylindrical axial direction of the outer surface of the surface layer. An image forming apparatus includes the electrophotographic photoreceptor; and a peripheral member capable of contacting a surface of the electrophotographic photoreceptor.

ELECTROPHOTOGRAPHIC PHOTORECEPTOR, AND ELECTROPHOTOGRAPHIC IMAGE FORMING METHOD AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS USING THE SAME
20200081360 · 2020-03-12 ·

An electrophotographic photoreceptor includes an outermost layer formed of a polymerized cured product of a composition containing a polymerizable monomer and metal oxide particles surface-treated with a surface treatment agent having a silicone chain, wherein a ratio (r/r) between a number average primary particle diameter (r) of metal oxide particles which are untreated base particles of the metal oxide particles surface-treated with the surface treatment agent having a silicone chain and a sphere equivalent particle diameter (r) of the untreated base particles calculated from a specific surface area measured by a nitrogen adsorption method is 1.5 or more and 6.0 or less, and a surface treatment amount with the surface treatment agent having a silicone chain per surface area of the untreated base particles is 0.0005 g/m.sup.2 or more and 0.0015 g/m.sup.2 or less.