Abstract: An electrophotographic toner containing: a fixing resin, a colorant, and wax. The wax at least contains hydrocarbon wax having a number-average molecular weight of not higher than 600, and polyethylene wax having a number-average molecular weight of not higher than 600, a melting viscosity of lower than 15 mPa·s at 140° C. and a crystallinity of lower than 95%. A ratio of the hydrocarbon wax to the polyethylene wax is in a range of from 1:10 to 2:1. A maximum of absorption peaks in a heat-up time absorption calorie curve in a DSC curve of the toner measured by a differential scanning calorimeter is at a temperature not higher than 75° C. An onset temperature in absorption of heat is not higher than 65° C.

Abstract: A multi-color printer (and a method therefor) includes a drum-shaped photosensitive body for black toner, a belt-shaped toner carrier for non-black color toner, a first transferring unit for transferring a color-toner image formed on the belt-shaped toner carrier to a medium, a second transferring unit for transferring a black toner image formed on the drum-shaped photosensitive body, the drum-shaped photosensitive body being disposed near the belt-shaped toner carrier, and a fusing unit for fusing to the medium the black toner image and the color toner image transferred to the paper.

Abstract: An electro-photographic apparatus includes a photosensitive body in the form of a photosensitive belt disposed for movement along a path in which a major portion of the path extends in a substantially vertical direction, and a plurality of developing units arranged in a vertical stack along one side of the substantially vertical path of the photosensitive body. A transfer unit is disposed adjacent to another side of the substantially vertical path of the photosensitive body, a fixing unit and a paper cassette are provided. A first transporting path is provided along which the print medium is transported in a substantially vertical direction from the paper cassette to the fixing unit via the transfer unit.

Abstract: Electrostatic image developing toner includes fixing resin; and wax. The wax is hydrocarbon-based wax. The wax is containing, as its constitutional components, first wax and second wax. The first wax is higher than 1.5 in ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), lower than 10 mPa·s in melt viscosity at 140° C. and higher than 75% and not higher than 85% in degree of crystallinity. The second wax is not higher than 1.5 in ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), lower than 10 mPa·s in melt viscosity at 140° C. and higher than 85% and not higher than 95% in degree of crystallinity.

Abstract: An electrophotographic toner containing: a fixing resin, a colorant, and wax. The wax at least contains hydrocarbon wax having a number-average molecular weight of not higher than 600, and polyethylene wax having a number-average molecular weight of not higher than 600, a melting viscosity of lower than 15 mPa·s at 140° C. and a crystallinity of lower than 95%. A ratio of the hydrocarbon wax to the polyethylene wax is in a range of from 1:10 to 2:1. A maximum of absorption peaks in a heat-up time absorption calorie curve in a DSC curve of the toner measured by a differential scanning calorimeter is at a temperature not higher than 75° C. An onset temperature in absorption of heat is not higher than 65° C.

Abstract: Electrostatic charge developing toner contains at least fixing resin, a coloring agent and wax. Wax having number average molecular weight of not higher than 600 is contained as a component of the wax. A volume average particle size of the toner is in a range of from 5 &mgr;m to 10 &mgr;m. Toner particles each having a particle size of not larger than 4 &mgr;m are contained by 10% or lower by number of the total number of toner particles.

Abstract: An electro-photographic apparatus includes a photosensitive body in the form of a photosensitive belt disposed for movement along a path in which a major portion of the path extends in a substantially vertical direction, and a plurality of developing units arranged in a vertical stack along one side of the substantially vertical path of the photosensitive body. A transfer unit is disposed adjacent to another side of the substantially vertical path of the photosensitive body, a fixing unit and a paper cassette are provided. A first transporting path is provided along which the print medium is transported in a substantially vertical direction from the paper cassette to the fixing unit via the transfer unit.

Abstract: Electrostatic image developing toner includes fixing resin; and wax. The wax is hydrocarbon-based wax. The wax is containing, as its constitutional components, first wax and second wax. The first wax is higher than 1.5 in ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), lower than 10 mPa·s in melt viscosity at 140° C. and higher than 75% and not higher than 85% in degree of crystallinity. The second wax is not higher than 1.5 in ratio of weight average molecular weight (Mw) to number average molecular weight (Mn), lower than 10 mPa·s in melt viscosity at 140° C. and higher than 85% and not higher than 95% in degree of crystallinity.

Abstract: A multi-color printer (and a method therefor) includes a drum-shaped photosensitive body for black toner, a belt-shaped toner carrier for non-black color toner, a first transferring unit for transferring a color-toner image formed on the belt-shaped toner carrier to a medium, a second transferring unit for transferring a black toner image formed on the drum-shaped photosensitive body, the drum-shaped photosensitive body being disposed near the belt-shaped toner carrier, and a fusing unit for fusing to the medium the black toner image and the color toner image transferred to the paper.

Abstract: An electro-photographic apparatus having a photosensitive body, a plurality of developing units for forming a toner image on a surface of the photosensitive body by attaching toner on a surface of the photosensitive body, a member for receiving a print medium, a first transporting path including a printing portion for transferring one toner image in a substantially vertical direction from the photosensitive body onto one side of the print medium and a fixing portion for fixing the transferred image so as to have a printed print medium and a second transporting path disposed substantially in parallel to and coupled to the first transporting path for returning the printed print medium to the first transporting path for enabling transfer of another toner image on an opposite side on the printed print medium. The printed print medium is transported along the first transporting path for fixing the transferred image on the opposite side of the printed print medium by the fixing portion.

Abstract: In an electrophotographic apparatus, regions having at least three different potential levels Vc, Vw, and Vr are formed on a photosensitive member by using an exposing device, and developing processes respectively using colored particles of different kinds are performed by normal development and reversal development on two potential levels Vc and Vr excluding the intermediate potential level Vw. The apparatus has an auxiliary exposing unit for forming a fringe development preventing potential in an edge of an image forming region in order to prevent fringe development from occurring. The auxiliary exposing unit sets an auxiliary exposure amount by performing pulse-width modulation on a laser driver.

Abstract: A printing system is provided which ensures easy formation of a plate and regeneration of the plate for continued use. The press plate used in a the printing system to form an image using a water-based ink is characterized in that, (I) prior to formation of a latent image, the surface forming the latent image exhibits extra ink-repellency to the ink to be used; (2) the press plate allows a water soluble material forming the latent image to be deposited thereon; (3) the latent image can be formed by allowing the water soluble material to be deposited on the press plate surface; and (4) the press plate can be regenerated as a plate which allows a new latent image to be formed by washing the press plate with water and drying it, upon completion of ensuing processes of development and transfer.

Abstract: Electrostatic charge developing toner contains at least fixing resin, a coloring agent and wax. Wax having number average molecular weight of not higher than 600 is contained as a component of the wax. A volume average particle size of the toner is in a range of from 5 &mgr;m to 10 &mgr;m. Toner particles each having a particle size of not larger than 4 &mgr;m are contained by 10% or lower by number of the total number of toner particles.

Abstract: Toner for developing an electrostatic charge image comprises: polyethylene wax having a value (Mw/Mn) of weight average molecular weight/number average molecular weight which is larger than 1.5, melt viscosity lower than 10 mPa•s at 140° C., and degree of crystallinity lower than 90%.

Abstract: In an electrophotographic apparatus, regions having at least three different potential levels Vc, Vw, and Vr are formed on a photosensitive member by using an exposing device, and developing processes respectively using colored particles of different kinds are performed by normal development and reversal development on two potential levels Vc and Vr excluding the intermediate potential level Vw. The apparatus has an auxiliary exposing unit for forming a fringe development preventing potential in an edge of an image forming region in order to prevent fringe development from occurring. The auxiliary exposing unit sets an auxiliary exposure amount by performing pulse-width modulation on a laser driver.

Abstract: The object of the present invention is to provide a printing system ensuring easy formation of a plate and regeneration of said plate, and a press plate thereof.

Abstract: An electro-photographic apparatus having a photosensitive body, at least one developing unit for forming a toner image on a surface of the photosensitive body by attaching toner on a surface of the photosensitive body, a member for receiving a print medium, a first transporting path including a printing portion for transferring one toner image from the photosensitive body onto one side of the print medium and a fixing portion for fixing the transferred image so as to have a printed print medium and a second transporting path coupled to the first transporting path for returning the printed print medium to the first transporting path for enabling transfer of another toner image on an opposite side on the printed print medium. The printed print medium is transported along the first transporting path for fixing the transferred image on the opposite side of the printed print medium by the fixing portion.

Abstract: An electrophotographic printing apparatus using electric potential dividing development processing without the occurrence of primary fringe and fringe caused by auxiliary exposure has reverse electric fields causing primary fringe and fringe caused by auxiliary exposure adjusted to be nearly equal to each other. The auxiliary exposure is applied to an area surrounding one image, and an electric potential of an intermediate electric potential zone is brought close to a bias electric potential of another image which is not subjected to auxiliary exposure.

Abstract: An electro-photographic apparatus including a photosensitive body, a plurality of developing units for forming a toner image on a surface of the photosensitive body by attaching toner on the surface of the photosensitive body, an intermediate transfer body for having the toner image transferred thereon and for transferring the toner image onto a print medium, and a paper cassette for containing the print medium. The paper cassette and the developing units are arranged to be horizontally detachable in the same direction.

Abstract: In an electrophotographic printing apparatus for printing using a three level printing method, there are provided a first color data memory and a second color data memory which memorize the pixel data of every color sent from host equipment, such as a computer connected to an electrophotographic printing apparatus, and by the use of image recognition equipment for judging whether pixel information is part of what image, exposure information with exposure equipment is determined so that the electric current flowing into electric current source and electric current source is changed. With such an arrangement, the exposure data for every color to be printed is created on the basis of the recognized result the part of a particular image that the pixel data shows, and the color image of the line-width in accordance with data sent from the host equipment to the electrophotographic printing apparatus can be actually printed by controlling the exposure beam diameter.