Canon Kabushiki Kaisha

Takashi Kusaba

Akihiko Nakazawa

Atsushi Tanaka

Tsunenori Ashibe

Hiroyuki Kobayashi

Hidekazu Matsuda

Yuji Sakurai

Akira Shimada

Shohei Urushihara

Masaki Yamada

Minoru Nakamura

Minoru Shimojo

Kunimasa Kawamura

Ryota Kashiwabara

Toshio Takamori

Toru Ishii

Ryo Sugiyama

Masashi Uno

Akihiko Nakazwa

Hidehiko Matsuda

A developing roller includes: a mandrel; an elastic layer provided for an outer periphery of the mandrel, the elastic layer including an addition-curing silicone rubber; and a surface layer provided for an outer periphery of the elastic layer, in which: the elastic layer includes a compound represented by the following formula (1); when the content of such a compound that n in the formula (1) represents an integer of 3 to 12 in the elastic layer is represented by P1, and the content of such a compound that n in the formula (1) represents an integer of 13 to 20 in the elastic layer is represented by P2, P1+P2 is 5,000 ppm by mass to 12,000 ppm by mass; and P1 is 1,500 ppm by mass to 6,000 ppm by mass (In the formula (1), n represents an integer of 3 to 20): 

Developing member including elastic member containing cured product of addition-curing silicone rubber mixture, processing cartridge including the developing member, and electrophotographic apparatus including the developing member

Provided is a developing roller including elastic layer and resin layer adhered to each other and having an appropriately resistance, thereby suppressing fogging. The developing member comprises a mandrel; an elastic layer; and a resin layer, wherein: the resin layer comprises polyurethane resin obtained by isocyanate and polyol; and the elastic layer includes cured silicone rubber composition comprising (a)-(d): 

Developing member

A developing roller including a mandrel, an elastic layer provided on the mandrel and containing a cured material of an addition curable-type dimethyl silicone rubber, and a surface layer containing a urethane resin that covers the circumferential surface of the elastic layer. The urethane resin has a structure represented by the following formula (1), and one or both structures selected from a structure represented by the following formula (2) and a structure represented by the following formula (3) between two adjacent urethane linkages. 

Developing roller, process cartridge, and electrophotographic apparatus

There is provided a process for producing a regenerated elastic roller which can be again used for the formation of high-quality electrophotographic images by sufficiently relaxing a compression set of the elastic roller having the compression set caused in an elastic layer in usage. The process for producing a regenerated elastic roller includes a step of heating an elastic roller having a conductive mandrel and an elastic layer and having a compression set caused in the elastic layer, in a cylindrical mold to thermally expand the elastic layer and to cause a surface of the elastic roller to contact an inner wall of the cylindrical mold.

Process for producing regenerated elastic roller

The electrophotographic belt of the present invention is characterized that, in the electrophotographic belt composed of the thermoplastic resin composition containing thermoplastic resin, with respect to a flake-shaped portion having an arc length of 5% of the inner peripheral length of the electrophotographic belt, when the thickness of the flake-shaped portion is measured at intervals of 1 mm in the peripheral direction, the difference between the maximum value and the minimum value of the measured value is 2% or more and 20% or less of an arithmetic average value.

Electrophotographic belt, production method of electrophotographic belt, and electrophotographic apparatus

A developing roller having an elastic layer on the outer periphery of a mandrel and having a surface layer containing a resin and resin particles on its outer periphery, wherein the surface layer has a convex portion attributable to the resin particles, and has a surface of roughness in which a distortion degree Rsk of a roughness curve is 0.15 or more and 0.70 or less, wherein the resin particles have a peak Pat a particle diameter din a volume particle size distribution, and wherein 'a', 'b', &#x201c;c&#x201d;, d, dand dsatisfy a specific relationship, where, &#x201c;a&#x201d; denotes a volume fraction of the resin particle having the particle diameter din the volume particle size distribution, and &#x201c;b&#x201d; and &#x201c;c&#x201d; denote volume fractions at particle diameters dand drespectively in the volume particle size distribution.

Developing roller, developing apparatus using the same, and image forming apparatus

An electrophotographic endless belt containing a polyamide resin, carbon black and a filler, characterized in that the polyamide resin is at least one resin selected from the group consisting of polyamide 610, polyamide 612, polyamide 11 and polyamide 12, the filler is at least one filler selected from the group consisting of an oxide, a hydroxide, a carbonate and a silicate, and weight (A) of the polyamide resin and total weight (B) of the carbon black and the filler is in a ratio (A:B) of from 90:10 to 50:50. Also disclosed are an electrophotographic apparatus having the electrophotographic endless belt, and a process for producing the electrophotographic endless belt.

Electrophotographic endless belt, electrophotographic apparatus having electrophotographic endless belt, and process for producing electrophotographic endless belt

In an electrophotographic belt member comprising a resin composition, the resin composition contains from 30% by weight to 90% by weight of a thermoplastic resin, from 2% by weight to 30% by weight of a compound selected from the group consisting of a polyether-ester amide, a polyether ester and a polyether amide, from 0% by weight to 5% by weight of an electrolyte, and from 2% by weight to 50% by weight of an insulating filler. Also disclosed are a process for producing the electrophotographic belt member, and an electrophotographic apparatus having the electrophotographic belt member.

Electrophotographic belt member, process for producing electrophotographic belt member, and electrophotographic apparatus

In an electrophotographic endless belt having a resin layer formed of a resin composition containing a polyamide, the resin composition further contains a copolymer obtained by copolymerization of an olefin and an oxygen-containing heterocyclic compound, a curve (T-log&#x3b7; curve) showing the relationship between temperature T (&#xb0; C.) and common logarithm log&#x3b7; of melt viscosity &#x3b7; (Pa&#xb7;s), of the resin composition has, in the range of log&#x3b7; of from log1,000 to log8,000, a gently inclined region the inclination &#x394; log&#x3b7;/&#x394;T of which is from &#x2212;0.02 to 0, and the gently inclined region has a temperature range of 10&#xb0; C. or more, and the resin layer has a thickness the maximum thickness of which is 115% or less of the average value of the thickness of the resin layer and the minimum thickness of which is 85% or more of the average value of the thickness of the resin layer. Also disclosed is a process for producing the above electrophotographic endless belt.

Electrophotographic endless belt, process for producing electrophotographic endless belt, and electrophotographic apparatus

An electrophotographic endless belt has a beltlike substrate and a meandering-preventive member attached to the inner peripheral surface of the beltlike substrate via a pressure-sensitive adhesive, double-coated tape. The pressure-sensitive adhesive, double-coated tape is a pressure-sensitive adhesive, double-coated tape having i) a reinforcing base material and ii) pressure-sensitive adhesive layers on both sides of the reinforcing base material. The reinforcing base material has a thickness of from 25 &#x3bc;m or more to 200 &#x3bc;m or less, and the pressure-sensitive adhesive layers on both sides each have a thickness of 200 &#x3bc;m or less and at least one of the pressure-sensitive adhesive layers has a thickness of from more than 100 &#x3bc;m to 200 &#x3bc;m or less, and the meandering-preventive member has a hardness of from 15&#xb0; or more to 70&#xb0; or less. Also disclosed are a process cartridge and an electrophotographic apparatus which have the electrophotographic endless belt as an intermediate transfer belt.

Electrophotographic endless belt, process cartridge, and electrophotographic apparatus

An electrophotographic endless belt has a belt-like substrate, and a meandering-preventive member for preventing the electrophotographic endless belt from meandering and a position detection member for detecting a prescribed position of the electrophotographic endless belt. The meandering preventive member is, disposed on the inner-periphery side of one end portion of the belt-like substrate, and the position detection member is disposed on the outer-periphery side of the other end portion of the belt-like substrate. The meandering-preventive member and the position detection member are kept apart by a distance of from 200 mm to 250 mm in the width direction of the electrophotographic endless belt. A process cartridge and an electrophotographic apparatus employ such an electrophotographic endless belt as an intermediate transfer belt.

Endless belt comprising a meandering-prevention member, and a process cartridge and an electrophotographic apparatus using such an endless belt

In an electrophotographic endless belt having a beltlike substrate, a meandering-preventive member and a position detection member, the meandering-preventive member is disposed on the inner-periphery side of one end portion of the beltlike substrate, the position detection member is disposed on the outer-periphery side of the other end portion of the beltlike substrate, and the meandering-preventive member and the position detection member are 200 mm to 250 mm away from each other in the width direction of the electrophotographic endless belt. The beltlike substrate contains a thermoplastic resin as a binder resin, and the beltlike substrate has a 25 &#x3bc;m&#xd7;25 &#x3bc;m surface total current value of from 300 nA to 2,000 nA at the time of application of 100 V as measured by SPM.

Electrophotographic endless belt comprising meandering-preventive member, and process cartridge and electrophotographic apparatus having such an endless belt

An endless belt for electrophotography is disclosed which is obtainable continuously by melt extrusion from a circular die. The endless belt has a layer containing a thermoplastic resin having a diphenyl sulfone structure represented by the following Formula (1)Also disclosed are a process for producing the endless belt and an image forming apparatus having the endless belt.

Endless belt electrophotography, process for producing the endless belt, and image forming apparatus having the endless belt

A process cartridge which is detachably mountable to a main body of an electrophotographic apparatus, includes an electrophotographic photosensitive member to carry a toner image; an intermediate transfer belt having a contact part with the photosensitive member, and a primary transfer unit to primarily transfer the toner image at the contact part from the photosensitive member to the intermediate transfer belt, being integrally supported in one body. After the contact part is formed by the photosensitive member and the intermediate transfer belt is brought into contact with under a linear pressure of 0.5 N/cm and is left for 10 hours in an environment of 45&deg; C./95% RH, differences in the dark portion potential and the light portion potential of the photosensitive member between the contact part and the non-contact part of the photosensitive member are respectively less than 20%, and no crack having a length of not less than 1 mm occurs in any of the surfaces of the photosensitive member and the intermediate transfer belt. An electrophotographic apparatus having the process cartridge is also disclosed.

Process cartridge and electrophotographic apparatus having an intermediate transfer belt

A process cartridge integrally supports therein a cylindrical latent-image-bearing member on which a toner image is formed and an intermediate transfer belt to which the toner image is primarily transferred and from which it is secondarily transported to a transfer medium. To prevent the latent-image-bearing member from being unwantedly triboelectrically charged during transportation, the cartridge satisfies any of requirements that A) the latent-image-bearing member has a surface potential Vt of &minus;200 V&lE;Vt&lE;200 V when the intermediate transfer belt and the latent-image-bearing member are rubbed with each other, B) a spacer member is provided between the intermediate transfer belt and the latent-image-bearing member, and the latent-image-bearing member has a surface potential Vt of &minus;200 V&lE;Vt&lE;200 V when the former and the latter are rubbed with each other, and C) the cartridge has a device for lowering contact pressure of the intermediate transfer belt against the latent-image-bearing member.

Growing community of inventors

Shizuoka, Japan

Takashi Kusaba