Electrophotographic photosensitive member and process for forming electrophotographic images using same

Claim 2

A process for forming electrophotographic images which comprises developing, with a developer comprising ceramic fine powders of non-oxide type, electrostatic latent images formed on an electrophotographic photosensitive member comprising a photosensitive layer overlying an electroconductive substrate where the surface hardness of the photosensitive layer is 10 g. or more which is a vertical load necessary for forming a scratch of 50 μm wide when the vertical load is applied to a diamond or sapphire cone pressing member, the conical angle being 90° and the tip being a semispheric shape having a diameter of 0.01 mm and the cone pressing member is moved on the surface of the photosensitive layer at the speed of 50 mm/min, transferring the images thus developed and then cleaning the photosensitive member.

Claim 3

A process for forming electrophotographic images according to claim 1 in which SiC fine powders are used as the cderamic fine powders of non-oxide type.

Claim 4

A process for forming electrophotographic images according to claim 1 in which the developer contains additionally ceramic fine powders of oxide type.

Claim 5

A process for forming electrophtographic images according to claim 3 in which the ceramic fine powders of oxide type are silica fine powders.

Claim 6

A process for forming electrophotographic images which comprises developing, with a developer comprising a magnetic toner, ceramic fine powders of oxide type and ceramic fine powders of non-oxide type, electrostatic latent images formed on an electrophotographic photosensitive member comprising a photosensitive layer overlying an electroconductive substrate where the surface hardness of the photosensitive layer is 10 g. or more which is a vertical load necessary for forming a scratch of 50 μm wide when the vertical load is applied to a diamond or sapphire cone pressing member, the conical angle being 90° and the tip being a semispheric shape having a diameter of 0.01 mm and the cone pressing member is moved on the surface of the photosensitive layer at the speed of 50 mm/min, transferring the images thus developed and then cleaning the photosensitive member.

Claim 7

A process for forming electrophotographic images which comprises developing, with a developer comprising a magnetic toner, ceramic fine powders of oxide type and ceramic fine powders of non-oxide type, electrostatic latent images formed on an electrophotographic photosensitive member comprising a photosensitive layer overlying an electroconductive substrate where the surface hardness of the photosensitive layer is 10 g. or more which is a vertical load necessary for forming a scratch of 50 μm wide when the vertical load is applied to a diamond or sapphire cone pressing member, the conical angle being 90° and the tip being a semispheric shape having a diameter of 0.01 mm and the cone pressing member is moved on the surface of the photosensitive layer at the speed of 50 mm/min, transferring the images thus developed and then cleaning the photosensitive member.

Claim 8

A process for forming electrophotographic images according to claim 5 in which the ceramic fine powders of oxide type are silica fine powders and the ceramic fine powders of non-oxide type are SiC fine powders.

Claim 9

A process for forming electrophotographic images which comprises developing, with a developer comprising a magnetic toner, ceramic fine powders of non-oxide type and a lubricant, electrostatic latent images formed on an electrophotographic photosensitive member comprising a photosensitive layer overlying an electroconductive substrate where the surface hardness of the photosensitive layer is 10 g. or more which is a vertical load necessary for forming a scratch of 50 μm wide when the vertical load is applied to a diamond or sapphire cone pressing member, the conical angle being 90° and the tip being a semispheric shape having a diameter of 0.01 mm and the cone pressing member is moved on the surface of the photosensitive layer at the speed of 50 mm/min, transferring the images thus developed and then cleaning the photosensitive member.

Claim 10

A process for forming electrophotographic images which comprises developing, with a developer comprising a magnetic toner, ceramic fine powders of non-oxide type and a lubricant, electrostatic latent images formed on an electrophotographic photosensitive member comprising a photosensitive layer overlying an electroconductive substrate where the surface hardness of the photosensitive layer is 10 g. or more which is a vertical load necessary for forming a scratch of 50 μm wide when the vertical load is applied to a diamond or sapphire cone pressing member, the conical angle being 90° and the tip being a semispheric shape having a diameter of 0.01 mm and the cone pressing member is moved on the surface of the photosensitive layer at the speed of 50 mm/min, transferring the images thus developed and then cleaning the photosensitive member.

Claim 11

A process for forming electrophotographic images according to claim 7 in which the ceramic fine powders of non-oxide type are SiC fine powders.

Claim 12

A process for forming electrophotographic images according to claims 1, 5 or 7 including employing a photosensitive layer having a laminate structure comprising a charge generation and a charge transport layer.

Claim 13

A process for forming the electrophotographic images according to claims 1, 5 or 7 including employing a photosensitive member comprising, in sequence, an electroconductive substrate, a charge generation layer and a charge transport layer.

Claim 14

A process for forming electrophotographic images according to claim 10 including utilizing a charge transport layer formed of a binder resin selected from the group consisting of acrylic resins, styrene resins, polyester resins, polycarbonates, polyarylate, polysulfone, polyphenylene oxide, epoxy resins, polyurethane resins, alkyd resins and unsaturated resins.

Claim 15

A process for forming electrophotographic images according to claim 11 including selecting the binder resin from the group consisting of poly(methyl methacrylate), polystyrene, styrene-acrylonitrile copolymers, polycarbonates and diallylphthalate resins.

Claim 16

A process for forming electrophotographic images according to claim 9 including employing a photosensitive layer formed from (1) an organic photoconductive polymer or (ii) low molecular weight organic photoconductive materials dispersed in an insulating polymer.

Claim 17

A process for forming electrophotographic images according to claim 9 including employing a charge transport layer comprising a charge transport material and a binder resin in a weight ratio of from about 2:1 to 1:2.

Claim 18

A process for forming electrophotographic images according to claim 9 including employing a charge generation layer comprising a charge generation material and a binder resin in a weight ratio of 0.5 to 4 parts binder resin per part charge generation material.