Patent application number | Description | Published |
20090052934 | IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD - The present invention provides an image forming apparatus and an image forming method capable of effectively suppressing the occurrence of image deletion etc. and thus stably obtaining a high-quality image and stably reducing the influence of titanium oxide particles on image quality. The image forming apparatus includes an amorphous silicon photoconductor drum having a heater provided therein; a charging device; and a rotating member that cleans the surfaces of the amorphous silicon photoconductor drum using titanium oxide particles included in toner particles. In the image forming apparatus and the image forming method using the same, the heater controls a difference between the surface temperature of the amorphous silicon photoconductor drum and the outdoor temperature within a predetermined range, and slide friction between the amorphous silicon photoconductor drum and the rotating member and the average primary particle diameter of the titanium oxide particles are set in predetermined ranges. | 02-26-2009 |
20090232544 | IMAGE FORMING APPARATUS - An image forming apparatus includes a plurality of image forming units arranged in parallel, each image forming unit having an image carrying member and a charging roller disposed face to face with the image carrying member for electrically charging the image carrying member, and a shifting mechanism for selectively shifting at least one charging roller between a first position where the charging roller is brought into contact with the corresponding image carrying member to electrically charge the image carrying member in contact manner and a second position where the charging roller is moved away from the corresponding image carrying member to electrically charge the image carrying member in non-contact manner. | 09-17-2009 |
20090324268 | IMAGE FORMING APPARATUS - A bias corrector conducts a first bias correction calculation by performing first through third calculations. The first calculation compares a stored target charging current value to a first charging current value detected when a first charging bias was applied by a bias applying device. The second calculation is performed repeatedly to calculate a second charging bias based on the comparison result and then to compare the target charging current value to a second charging current value detected by the current detector when the second charging bias was applied by the bias applying device. The third charging bias is calculated based on the comparison result. A second bias correction calculation then is conducted to correct the charging bias obtained as a result of the first bias correction calculation based on photoconductor information detected by a photoconductor information detector. | 12-31-2009 |
20110299866 | IMAGE FORMING APPARATUS - An image forming apparatus of the present invention has first and second image carriers that are configured by positively-charged single layer type electrophotographic photoreceptors, and a controller that controls an operation for charging or destaticizing the circumferential surfaces of these image carriers. The controller switches between a first mode for causing the first and second image carriers to perform image formation while rotating these image carriers, and a second mode for causing only the first image carrier to perform image formation while rotating the first and second image carriers. In the second mode, the second image carrier is applied with a charging bias and subjected to a destaticizing operation without undergoing a developing operation. The first image carrier is applied with the charging bias and subjected to the developing operation and the destaticizing operation. | 12-08-2011 |
20110299887 | IMAGE FORMING APPARATUS - An image forming apparatus includes a positively-charged single layer type electrophotographic photoreceptor, a charging device with a contact charging roller for charging a surface of the photoreceptor and an exposure device for exposing the charged surface of the photoreceptor to light to form an electrostatic latent image thereon. A developing device develops the electrostatic latent image into a toner image and a transfer device transfers the toner image to a transferred body. The charging roller is made of electrically conductive rubber having an Asker-C rubber hardness of 62 to 81°. A roller surface roughness of the charging roller has an average distance (Sm) between asperity peaks on a cross-sectional curve of 55 to 130 μm and that a ten-point average roughness (Rz) is 9 to 19 μm. The image forming apparatus is capable of preventing carrier trapping, film peeling and uneven charging in the photoreceptor. | 12-08-2011 |
20110299888 | IMAGE FORMING APPARATUS - An image forming apparatus has: a positively-charged single layer type electrophotographic photoreceptor; a charging device with a contact charging roller for charging a surface of the photoreceptor; an exposure device for exposing the charged surface to light to form an electrostatic latent image on the surface of the photoreceptor; a developing device for developing the electrostatic latent image into a toner image; and a transfer device for transferring the toner image to a transferred body. The photoreceptor has a conductive substrate and a photosensitive layer that contains a charge generating agent, a charge transport agent and a binder resin. The binder resin has a yield point strain of 9 to 29%, and the contact charging roller has a conductive layer with a thickness of 1 mm to 3 mm. The image forming apparatus is environmentally responsive and having a long-lasting positively-charged single layer type photoreceptor and charging roller. | 12-08-2011 |
20110299890 | IMAGE FORMING APPARATUS - The present invention provides an image forming apparatus, including: an image carrier configured by a positively charged single-layer electrophotographic photosensitive body; a charging device which is based on a contact charging method for charging a circumferential surface of the image carrier while making contact with the circumferential surface of the image carrier; and a transfer unit which transfers a toner image on the circumferential surface of the image carrier to a transfer receiving body by gripping the transfer receiving body with the image carrier, wherein the transfer unit includes an application unit to which a transfer bias is applied, and a region having a volume resistivity of 10 | 12-08-2011 |
20110299891 | IMAGE FORMING APPARATUS - An image forming apparatus, having: an image carrier configured by a positively charged single-layer electrophotographic photosensitive body; a charging device which is based on a contact charging method for charging a circumferential surface of the image carrier while making contact with the circumferential surface of the image carrier; a developing roller which is disposed so as to oppose the image carrier and carry and convey toner on the circumferential surface; and a voltage application unit which applies a developing bias to the developing roller, wherein the frequency of an AC component of the developing bias applied by the voltage application unit is 2.6 to 4.2 kHz. | 12-08-2011 |
20130343783 | IMAGE FORMING APPARATUS - An image forming apparatus includes a positively-charged single layer type electrophotographic photoreceptor, a charging device with a contact charging roller for charging a surface of the photoreceptor and an exposure device for exposing the charged surface of the photoreceptor to light to form an electrostatic latent image thereon. A developing device develops the electrostatic latent image into a toner image and a transfer device transfers the toner image to a transferred body. The charging roller is made of electrically conductive rubber having an Asker-C rubber hardness of 62 to 81°. A roller surface roughness of the charging roller has an average distance (Sm) between asperity peaks on a cross-sectional curve of 55 to 130 μm and that a ten-point average roughness (Rz) is 9 to 19 μm. The image forming apparatus is capable of preventing carrier trapping, film peeling and uneven charging in the photoreceptor. | 12-26-2013 |