Abstract: A developing device for electrophotographic image has a developing mechanism having a developer carrier for carrying a developer along a preset circulating route including a developing area and a developer restricting element for restricting the developer on the developer carrier, and a developer supply mechanism having a storing unit. The storing unit is filled with a start-up developer in the vicinity of the developer carrier and a replenishing developer remoter than the start-up developer from the developer carrier. The start-up developer and the replenishing developer have different grain sizes or grain size distributions. Further, a developing method for electrophotograhic image has the steps of using the start-up developer at an initial state of use of the developing mechanism, and using the replenishing developer differed in grain size or grain size distribution from the start-up developer after an end of the initial state of use of the developing mechanism.

Abstract: A developing device for electrophotographic image has a developing mechanism having a developer carrier for carrying a developer along a preset circulating route including a developing area and a developer restricting element for restricting the developer on the developer carrier, and a developer supply mechanism having a storing unit. The storing unit is filled with a start-up developer in the vicinity of the developer carrier and a replenishing developer remoter than the start-up developer from the developer carrier. The start-up developer and the replenishing developer have different grain sizes or grain size distributions. Further, a developing method for electrophotograhic image has the steps of using the start-up developer at an initial state of use of the developing mechanism, and using the replenishing developer differed in grain size or grain size distribution from the start-up developer after an end of the initial state of use of the developing mechanism.

Abstract: In a method for forming a multicolored toner image in accordance with an electrophotographic process, the addition amount of external additives to a non-added toner is 1.5 to 10.0 parts by weight per 100 parts by weight of the non-added toner in each developing step, the aggregation degree of the toner is within the range of 30 to 80%, and the change ratio of the aggregation degree satisfies the relation: 0.8?(initial aggregation degree/aggregation degree after no-load revolution of developing portion for 20 hours)?1.2. According to this method, it becomes possible to form a high-quality color image while a toner always keeps a stable degree of aggregation and a charge amount.

Abstract: An image formation method for forming an image is proposed, which uses an image formation apparatus capable of performing (1) multi-color image formation and printing by superimposing toner images with different colors by use of a plurality of color toners with different colors, including at least a black toner, and (2) monochrome image formation and printing, using only a black toner, with a maximum transferable amount of each color toner onto the image being in a range of 4×10−3 kg/m2 to 8×10−3 kg/m2, wherein an image glossiness (GKC) obtained by the black toner in the maximum transferable amount thereof at the multi-color image printing, an image glossiness (GCC) obtained by each of the color toners other than the black toner in the maximum transferable amount thereof at the multi-color image printing, and an image glossiness (GKM) obtained by the black toner in the maximum transferable amount thereof at the monochrome image printing satisfy a particular relationship as described in

Abstract: A color toner for electrophotography, preferably used as a flash fixing toner which can be processed at a high speed, and exhibit excellent fixing property, high image resolution (image reproducibility) when fixed, and color reproducibility by color overlapping, and having a preferable color tone, with which a multi-color image can be formed. The color toner for electrophotography is used for the extreme bottom layer of a multi-color image comprised of laminating at least two types of toners that are selected from black toner, magenta toner, yellow toner, and cyan toner, and contains a coloring agent and an infrared ray absorbent, the color toner for electrophotography has a contrast ratio in the range of 35% to 95%.

Abstract: A color toner for electrophotography, preferably used as a flash fixing toner which can be processed at a high speed, and exhibit excellent fixing property, high image resolution (image reproducibility) when fixed, and color reproducibility by color overlapping, and having a preferable color tone, with which a multi-color image can be formed. The color toner for electrophotography is used for the extreme bottom layer of a multi-color image comprised of laminating at least two types of toners that are selected from black toner, magenta toner, yellow toner, and cyan toner, and contains a coloring agent and an infrared ray absorbent, the color toner for electrophotography has a contrast ratio in the range of 35% to 95%.

Abstract: An image formation method for forming an image is proposed, which uses an image formation apparatus capable of performing (1) multi-color image formation and printing by superimposing toner images with different colors by use of a plurality of color toners with different colors, including at least a black toner, and (2) monochrome image formation and printing, using only a black toner, with a maximum transferable amount of each color toner onto the image being in a range of 4×10−3 kg/m2 to 8×10−3 kg/m2, wherein an image glossiness (GKC) obtained by the black toner in the maximum transferable amount thereof at the multi-color image printing, an image glossiness (GCC) obtained by each of the color toners other than the black toner in the maximum transferable amount thereof at the multi-color image printing, and an image glossiness (GKM) obtained by the black toner in the maximum transferable amount thereof at the monochrome image printing satisfy a particular relationship as described in

Abstract: An image formation method for forming an image is proposed, which uses an image formation apparatus capable of performing (1) multi-color image formation and printing by superimposing toner images with different colors by use of a plurality of color toners with different colors, including at least a black toner, and (2) monochrome image formation and printing, using only a black toner, with a maximum transferable amount of each color toner onto the image being in a range of 4×10−3 kg/m2 to 8×10−3 kg/m2, wherein an image glossiness (GKC) obtained by the black toner in the maximum transferable amount thereof at the multi-color image printing, an image glossiness (GCC) obtained by each of the color toners other than the black toner in the maximum transferable amount thereof at the multi-color image printing, and an image glossiness (GKM) obtained by the black toner in the maximum transferable amount thereof at the monochrome image printing satisfy a particular relationship as described in

Abstract: An image formation process which forms a toner image by the nonmagnetic one-component developing system by bringing an electrically conducting brush impressed with a voltage into contact with a photosensitive material to effect the uniform charging, and forming an electrostatic latent image on the photosensitive material by the exposure to the image-bearing light, wherein the toner that is used as a circularity of from 0.92 to 0.98. The nonmagnetic one-component developing system minimizes irregular electric charging that stems from the use of the electrically conducting brush. This action is obtained even in full-color developing system which effects development many times.

Abstract: Disclosed is a color image forming apparatus in which a color image is formed by accumulating a visible image on an image transfer medium. The color image forming apparatus includes a plurality of forming means for forming the visible image on an image forming medium with a toner; and a plurality of transferring means for transfer the visible image onto the image transfer medium while bringing the visible image into contact with the image transfer medium.

Abstract: In a method for forming a color image by using a contact type nonmagnetic one-component developing device, a flat sheet-like blade made of a metal flexible member and having a distal end thereof chamfered is used inside the developing device in combination with a toner having a glass transition point of 55 to 70° C. and a weight average particle diameter of 6.0 to 10.0 &mgr;m, and containing up to 20 number % of particles having particle diameters of 5 &mgr;m or below, as a developer. The developing device is simple in construction, can provide high image quality and can, moreover, provide a highly reliable image formation method.

Abstract: Disclosed is a color image forming apparatus in which a color image is formed by accumulating a visible image on an image transfer medium. The color image forming apparatus includes a plurality of forming means for forming the visible image on an image forming medium with a toner; and a plurality of transferring means for transfer the visible image onto the image transfer medium while bringing the visible image into contact with the image transfer medium.