Abstract: A charging device for electrically charging an image bearing member, includes a contact charging member contactable to the image bearing member to charge the image bearing member, the contact charging member being supplied only with a DC voltage; and a contact member contacted to the charging member, wherein the image bearing member is adapted to carry a toner image of toner which contains an externally added material comprising silica, wherein work functions of the charging member, the contact member and the silica satisfy, (the work function of the contact member)>(the work function of the silica)>(the work function of the charging member).

Abstract: A plurality of cleaning blades are provided for removing remaining developer on an electrophotographic photosensitive body used for an image forming apparatus. The cleaning blades include an abutment portion that abuts on the electrophotographic photosensitive body, and lubricant including insulating particles and conductive particles coating the abutment portion. The particle size of each of the insulating particles at D50 by a volume regarded as a reference lies in a range of 0.2 to 1.0 ?m and the particle size of each of the conductive particles at D50 by a volume regarded as a reference lies in a range of 0.4 to 4.0 ?m, D50 being defined by the integration of volumes of particles calculated from a smaller particle size side that reaches 50% relative to a total integration thereof.

Abstract: An image forming apparatus includes a rotatable image bearing member on which an electrostatic latent image is formed; a charging member for being supplied with a charging voltage which is a DC voltage not having an AC voltage component and for contacting the bearing member to electrically charge a surface of the bearing member using an electric discharge; a transfer member for transferring onto a transfer material a toner image formed on the surface of the bearing member by developing the electrostatic latent image, at a transfer position; wherein the charging potential of the charging member is different between when the charging member provides a first region with a potential and when the charging member provides a second region with a potential, thus providing a predetermined potential difference between the first region and the second region, and wherein the transfer member is not supplied with a voltage when the second region is at the transfer position, where the first region is a region on the image b

Abstract: An electrophotographic image forming apparatus for forming an image on a recording material, to which a cartridge is detachably mountable, includes a) a cartridge including, a developer accommodating portion for accommodating a developer for developing an electrostatic latent image formed on an electrophotographic photosensitive member, a developing roller for developing an electrostatic latent image with a developer, a developer supply opening for supplying the developer to the developing roller form the developer accommodating portion, and a sealing member for unsealably sealing the developer supply opening; b) developer detecting means for detecting that amount of the developer deposited on a member to be detected is less than a predetermined level; c) sealing member retracting means for producing an electric signal for retracting the sealing member sealing the developer supply opening from a sealing position where the sealing member seals the developer supply opening, when the detecting means detects that

Abstract: The invention provides a developer carrying member for carrying a developer for developing an electrostatic image formed on an image bearing member, including an elastic layer, and a surface layer provided on a surface of the developer carrying member and including a resin and particles, wherein the particles have a property of being frictionally charged in a polarity opposite to a normal charging polarity of the developer, and the particles are exposed from the surface in an area rate within a range from 15 to 60% with respect to a surface area of the developer carrying member. In this manner, an uneven heating of the toner image can be suppressed even if the recording material generates an undulation after passing a nip.

Abstract: A developing apparatus including: a developer carrying member for carrying a developer, the developer carrying member being provided with an elastic layer and adapted to develop, with a developer, an electrostatic image formed on an image bearing member; wherein the developer includes a toner, the toner has a shape factor SF-1 of 100 or more but less than 130, the toner has a storage modulus G? (140° C.) at 140° C. of 2.0×103 dN/m2 or more but less than 2.0×104 dN/m2, the toner has a temperature, when the toner has a viscosity of 1.0×103 Pa·s in a flow tester temperature elevation method, of 115° C. or more but less than 130° C., and, in a surface roughness of the developer carrying member, a center-line mean roughness Ra, a ten-point mean roughness Rz and a mean spacing Sm of irregularities satisfy following relationships (1): 0.06 ? Rz / Sm ? 0.4 0.8 ? Ra ? 2.

Abstract: In a developing apparatus, the developing apparatus includes a developer carrying member which carries a developer and has elasticity, and a developer regulating member which regulates an amount of the developer carried on the developer carrying member, the developer regulating member having a supported part supported by a support member and a contact part which is in contact with the developer carrying member, in which the contact part has a ten point average surface roughness of larger than 2.0 ?m and a maximum height surface roughness of smaller than an average particle diameter of the developer. Therefore, an amount of the developer carried on the developer carrying member can be regulated to be uniform.

Abstract: There are provided an image forming apparatus, process cartridge, and storage medium which, if an image forming stop factor occurs in a cartridge of a certain color, enable image forming using a cartridge of another color and can increase the utilization efficiency and operability of the image forming apparatus. The image forming apparatus has a plurality of detachable process cartridges (8M, 8C, 8Y, 8K) including image carriers (photosensitive drums: 9M, 9C, 9Y, 9K) on which latent images are to be formed and developing units (12M, 12C, 12Y, 12K) which develop the latent images. When a replacement timing for at least one of the process cartridges has come, only the developing unit of the process cartridge (8K) whose replacement timing has not come is driven in accordance with the state of the cartridge whose replacement timing has come to perform image forming.

Abstract: A developer regulation member includes developer regulation means for regulating an amount of developer carried on a developer carrying member. The developer regulation means includes a first regulation portion formed of a first material which has a Shore D hardness of not less than 70 degrees or is metal, and a second regulation portion which is disposed opposite to the developer carrying member and is formed of a material different from the first material for the first regulation portion. The second regulation portion has an edge which is in contact with the developer carrying member.

Abstract: The invention provides a developer carrying member for carrying a developer for developing an electrostatic image formed on an image bearing member, including an elastic layer, and a surface layer provided on a surface of the developer carrying member and including a resin and particles, wherein the particles have a property of being frictionally charged in a polarity opposite to a normal charging polarity of the developer, and the particles are exposed from the surface in an area rate within a range from 15 to 60% with respect to a surface area of the developer carrying member. In this manner, an uneven heating of the toner image can be suppressed even if the recording material generates an undulation after passing a nip.

Abstract: In the present invention, a cleaning blade is provided, for removing remaining developer on an electrophotographic photosensitive body used for an image, forming apparatus comprises an abutment portion that abuts on the electrophotographic photosensitive body, lubricant including insulating particles and conductive particles being coated on the abutment portion, wherein a particle size of each of the insulating particles at D50 by a volume regarded as a reference lies in a range of 0.2 to 1.0 &mgr;m and a particle size of each of the conductive particles at D50 by a volume regarded as a reference lies in a range of 0.4 to 4.0 &mgr;m, the D50 being defined by that integration of volumes of particles calculated from a smaller particles size side arrives at 50% with relative to a total integration thereof, and so on.

Abstract: In the developing apparatus, the developer regulating member includes a developer carrying member which carries a developer and has elasticity, and a developer regulating member which regulates an amount of the developer carried on the developer carrying member, the developer regulating member having a supported part supported by a support member and a contact part which is in contact with the developer carrying member, in which the contact part has a ten point average surface roughness of larger than 2.0 &mgr;m and a maximum height surface roughness of smaller than an average particle diameter of the developer. Therefore, an amount of the developer carried on the developer carrying member can be regulated to be uniform.