Patent classifications
G03G15/0233
IMAGE FORMING APPARATUS
An image forming apparatus includes an apparatus main body, a conductive member, a contact spring, a hollow cylinder, and a drum unit attachable to and detachable from the apparatus main body. The conductive member is disposed in the drum unit. The contact spring is disposed in the apparatus main body and comes in electrically conductive contact with the conductive member. The hollow cylinder is disposed in the apparatus main body. The contact spring has a contact part and a helical spring part. The contact part is provided on the helical spring part. The contact part is retractable in and out of the hollow cylinder. The helical spring part is contained in the hollow cylinder and urges the contact part in a direction for causing the contact part to protrude from the hollow cylinder. The contact part has a longitudinal shape elongated along an axis of the helical spring part.
CHARGING MEMBER, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
A charging member includes a conductive substrate and a surface layer disposed on the conductive substrate. The surface layer includes an inorganic conductant agent including a metal and an organic conductant agent that includes a coordinating atom capable of coordinating to the metal and that has a molecular weight of 400 or less.
CHARGING ROLL
A charging roll includes a core member, a rubber base material disposed around the core member, and a surface layer disposed around the rubber base material. The ten point height of irregularities R.sub.Z of a surface of the surface layer is equal to or greater than 3.9 micrometers, and is equal to or less than 6.1 micrometers. The mean spacing between peaks S.sub.m of the surface of the surface layer is equal to or greater than 12.5 micrometers and is equal to or less than 13.5 micrometers.
ELECTRO-CONDUCTIVE MEMBER, MANUFACTURING METHOD THEREOF, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS
The electro-conductive member has an electro-conductive support, and an electro-conductive layer, in which the electro-conductive layer has a matrix including a first rubber cross-linked product and domains dispersed in the matrix, each of the domains includes a second rubber cross-linked product and electro-conductive particles, an outer surface of the electro-conductive member has concave portions, a surface of at least a part of the domains is exposed to the outer surface of the electro-conductive member at bottom portions of the concave portions, a volume resistivity of the matrix is greater than 1×10.sup.12 Ωcm, a volume resistivity of the electro-conductive layer is 1×10.sup.5 Ωcm to 1×10.sup.8 Ωcm, and A2 is 20 times or more of A1.
Process for producing an electrophotographic electroconductive member
A process for producing an electrophotographic electroconductive member having an electroconductive support and an electroconductive layer in the order mentioned. The electroconductive layer has a matrix including a crosslinked product of a first rubber, and a domain including a crosslinked product of a second rubber and an electroconductive particle, the process including the steps of: providing a rubber mixture for forming the domain, including carbon black and the second rubber by kneading the carbon black and the second rubber; providing a rubber mixture for forming the matrix, including the first rubber; kneading the rubber mixture for forming the domain and the rubber mixture for forming the matrix to prepare a rubber composition having a matrix-domain structure; forming a layer of the rubber composition on a surface of the electroconductive support; and curing the layer of the rubber composition on the surface of the electroconductive support to form the electroconductive layer.
Image forming apparatus with developer collection
Provided are an image bearing member; a charging member that charges the image bearing member; an exposure unit that exposes the image bearing member; a developing unit that develops an electrostatic latent image as a developer image by supplying a developer, charged to regular polarity, to the image bearing member; a transfer member that transfers the developer image to a transfer-receiving body; and a collecting member that collects a deposit on the image bearing member downstream of a transfer portion of the image bearing member at which the developer image is transferred to the transfer-receiving body by the transfer member, and upstream of a charging portion of the image bearing member charged by the charging member, in a rotation direction of the image bearing member. After transfer of the developer image to the transfer-receiving body, the developer remaining on the image bearing member is collected by the developing unit.
ELECTROCONDUCTIVE MEMBER, PROCESS CARTRIDGE, AND DEVICE FOR FORMING ELECTROPHOTOGRAPHIC IMAGE
The electrophotographic electroconductive member includes a support having an electroconductive outer surface, and an electroconductive layer on the surface of the support. The electroconductive layer has a matrix containing a crosslinked product of a first rubber, and domains dispersed in the matrix, and the domains each contain a crosslinked product of a second rubber and electroconductive particles. The matrix has a volume resistivity R1 of more than 1.0×10.sup.12 Ω.Math.cm, and the domains each have a volume resistivity R2 lower than the volume resistivity R1 of the matrix. The electroconductive layer further has a pore, and an inner wall of the pore is constituted by a part of the matrix and a part of the domains. The domains constituting the inner wall protrude into the pore at sites on the inner wall.
ELECTRO-CONDUCTIVE MEMBER, PROCESS CARTRIDGE, AND ELECTROPHOTOGRAPHIC IMAGE FORMING APPARATUS
Used is an electro-conductive member for electrophotography including: a support having an electro-conductive outer surface; and an electro-conductive layer on the outer surface of the support, wherein the electro-conductive layer includes: a matrix containing a first crosslinked rubber product and having a volume resistivity greater than 1.0×10.sup.12 Ωcm; and domains dispersed in the matrix, wherein the domain includes a second crosslinked rubber product and an electron conductive agent; and the electro-conductive layer includes a region T in which the volume resistivity of the matrix decreases in a depth direction from the outer surface of the electro-conductive member.
IMAGE FORMING APPARATUS
Provided are an image bearing member; a charging member that charges the image bearing member; an exposure unit that exposes the image bearing member; a developing unit that develops an electrostatic latent image as a developer image by supplying a developer, charged to regular polarity, to the image bearing member; a transfer member that transfers the developer image to a transfer-receiving body; and a collecting member that collects a deposit on the image bearing member downstream of a transfer portion of the image bearing member at which the developer image is transferred to the transfer-receiving body by the transfer member, and upstream of a charging portion of the image bearing member charged by the charging member, in a rotation direction of the image bearing member. After transfer of the developer image to the transfer-receiving body, the developer remaining on the image bearing member is collected by the developing unit.
Electroconductive roll
An electroconductive roll includes a core member, a rubber base material disposed around the core member, and a surface layer disposed around the rubber base material. The density of peaks S.sub.pd of the surface of the surface layer is equal to or greater than 93,406 (1/mm.sup.2), and is equal to or less than 153,027 (1/mm.sup.2).