JP2002148840A5 - - Google Patents

Description

Patent application title: Image forming apparatus

Claims (22)

An electrophotographic photosensitive member having at least a conductive substrate, a photoconductive layer formed on the conductive substrate, and a surface layer, a charging unit for charging the electrophotographic photosensitive member, and the image exposure by image exposure Latent image forming means for forming an electrostatic latent image on the body; developing means for visualizing the electrostatic latent image with toner on the electrophotographic photosensitive member to form a toner image; and transferring the toner image to a transfer material An image forming apparatus having a transfer unit
The surface layer of the electrophotographic photosensitive member is made of a non-single-crystal carbon film containing at least hydrogen, and the arithmetic average roughness (Ra) in the range of 10 μm × 10 μm on the surface is 0 to 100 nm.
The charging means has a conductive fine powder and a charging member for supporting the conductive fine powder on the surface, the conductive fine powder forms a contact portion with the electrophotographic photosensitive member, and the charging member Charging means for charging the electrophotographic photosensitive member by applying a voltage to the
The toner is a magnetic toner containing toner particles containing at least a binder resin and a magnetic substance, and an inorganic fine powder, and having an average circularity of 0.950 to 1.000, and is less than 79.6 kA / m. An image forming apparatus characterized in that the saturation magnetization is 10 to 50 Am ² / kg. The image forming apparatus according to claim 1, wherein an arithmetic average roughness (Ra) in a range of 10 μm × 10 μm of the surface of the electrophotographic photosensitive member is 5 to 80 nm. The image forming apparatus according to claim 1, wherein the photoconductive layer of the electrophotographic photosensitive member is made of a non-single-crystal material containing at least one of hydrogen and halogen and mainly containing silicon. The image forming apparatus according to any one of claims 1 to 3, wherein a hydrogen amount of the non-single-crystal carbon film is 41 atomic percent to 60 atomic percent with respect to the total amount of the carbon film. Between the photoconductive layer of the electrophotographic photosensitive member and the surface layer, it contains at least one of hydrogen and halogen, is mainly composed of silicon, and further contains at least one or more atoms selected from carbon, oxygen and nitrogen. The image forming apparatus according to any one of claims 1 to 4, further comprising: a buffer layer made of a non-single crystal material. The image forming apparatus according to claim 5, wherein the buffer layer further contains at least one or more atoms in Group 3B and Group 5B of the periodic table. The image forming apparatus according to any one of claims 1 to 6, wherein the surface layer is deposited by decomposition of a hydrocarbon gas by plasma CVD using a high frequency of 1 to 450 MHz. . The film according to any one of claims 1 to 6, wherein the surface layer is formed by decomposing at least a hydrocarbon gas by plasma CVD using a high frequency of 13.56 MHz or 105 MHz. The image forming apparatus according to claim 1. The charging unit is characterized in that the electrophotographic photosensitive member is charged while the surface of the charging member moves with a relative speed difference with respect to the surface of the electrophotographic photosensitive member at the contact portion. An image forming apparatus according to any one of claims 1 to 8. 10. The image forming apparatus according to claim 9, wherein the charging unit charges the electrophotographic photosensitive member while the charging member and the electrophotographic photosensitive member move in opposite directions in the contact portion. The image forming apparatus according to any one of claims 1 to 10, wherein the charging member is an elastic body having a porous surface. The image forming apparatus according to any one of claims 1 to 11, wherein the charging member is a roller member having an Asker C hardness of 50 degrees or less. The image forming apparatus according to claim 12, wherein the charging member is a roller member having an Asker C hardness of 25 degrees or more and 50 degrees or less. The image forming apparatus according to claim 1, wherein the charging member is a roller member having a volume resistivity of 1 × 10 ^{3 to} 1 × 10 ⁸ Ω · cm. The image forming apparatus according to any one of claims 1 to 14, wherein a resistance of the conductive fine powder is 1 × 10 ⁹ Ω · cm or less. 16. The apparatus according to any one of claims 1 to 15, wherein the developing means doubles as a cleaning means for collecting the toner remaining on the surface of the electrophotographic photosensitive member after transferring the visualized image onto the transfer material. Image forming device. The image forming apparatus according to any one of claims 1 to 16, wherein the conductive fine powder adheres to the surface of the toner. The conductive fine powder that adheres to the toner surface adheres to the electrophotographic photosensitive member by the developing device, remains on the electrophotographic photosensitive member and is conveyed after the transfer device, and reaches the charging device. The image forming apparatus according to claim 17, characterized in that: 17. The charging unit according to any one of claims 1 to 16, further comprising conductive fine powder replenishing means for containing the conductive fine powder and supplying the conductive fine powder to the surface of the charging member. The image forming apparatus according to claim 1. 20. The image forming apparatus according to claim 1, wherein the toner has an average circularity of 0.950 to 0.995. The image forming apparatus according to any one of claims 1 to 20, wherein the inorganic fine powder is hydrophobized. The image forming apparatus according to any one of claims 1 to 20, wherein the inorganic fine powder is hydrophobized with silicone oil.