Fuji Photo Film Company, Limited

Fujifilm Corporation

Chiaki Kawamoto

Chikashi Ohishi

Hidefumi Sera

Sho Nakao

Takao Nakayama

Koji Sonokawa

A plate making method of a lithographic printing plate precursor includes: exposing a lithographic printing plate precursor including an image-recording layer and a support; and developing the exposed lithographic printing plate precursor to prepare a lithographic printing plate, wherein the developing includes, in the following order, (i) a process of removing an unexposed area of the image-recording layer with a gum solution, (ii) a process of washing with water and (iii) a process of oil-desensitizing a non-image area with a gum solution.

Plate making method of lithographic printing plate precursor

The ink jet recording apparatus includes an ejection head for ejecting ink droplets toward a recording medium by exerting electrostatic force onto ink containing charged colorant particles, an ink tank for reserving the ink to be supplied to the ejection head, a circulation path for circulating the ink between the ejection head and the ink tank, and a cleaning mechanism for cleaning the ejection head and the circulation path using cleaning liquid. The cleaning liquid circulated through the circulation path at a time of cleaning by the cleaning mechanism is obtained by adding a charge control agent to an ink dispersion medium.

Ink jet recording apparatus

The ink jet recording device includes an ink jet recording head and an ink circulation system. The ink circulation system has an ink tank, an ink feeding unit, an ink supplying system and an ink recovery system. The ink feeding unit is provided in the ink tank, and has both a function to supply ink from the ink tank to the recording head through the ink supplying system and a function to stir the ink stored in the ink tank. The ink circulation system circulates the ink by supplying the ink to the recording head through the ink supplying system and recovering the ink supplied to the recording head through the ink recovery system.

A conductive layer,and a photoconductive layer,are laminated on a support member,made of resin so that an electrophotographic master plate for printing is constituted. Electrode portions,electrically connected to the conductive layer,are formed on the widthwise directional side surfaces. When development is performed, the electrode portions,are brought into contact with an electrode,adjacent to the support member,so that the potential of the conductive layer,is made to be the same as the potential of the electrode,adjacent to the support member,though the electrode portions,. The developing apparatus has a structure for causing the electrode portions,to be grounded by a provided roller made of stainless steel and/or a conductive brush.

Method and apparatus of developing electrophotographic master plate for printing

A liquid electrophotographic developing device for developing a charged and exposed photoconductive material which includes a photoconductive layer formed on one surface of a conductive layer. The liquid electrophotographic developing device is comprised of developing section, a developing solution tank provided in a housing and filled with a developing solution, conveying rollers for conveying the photoconductive materials, a developing electrode and a back electrode which are disposed parallel along a conveying path of the photoconductive material in the developing section, and a developing solution supplying device disposed above the developing electrode. The developing electrode is spaced part from the photoconductive layer, and the back electrode is disposed to come into contact with the back surface of the photoconductive material. Upon directly connecting the electrodes, toner particles contained in the developing solution adhere to the photoconductive layer to achieve development. The developing electrode does not touch the photoconductive layer to make a developed image free from soiling. The housing is covered with a lid to prevent the vaporizing of the developing solution. The developing solution is circulated through the developing section by a circulating device.

Liquid electrophotographic developing device and method thereof

A liquid electrophotographic developing device for developing a photoconductive material charged and exposed and which has a photoconductive layer formed on one surface of a conductive layer comprises a developing tank filled with a developing solution in which a developing electrode and a back electrode are disposed. The electrodes are immersed in the developing solution and disposed on either side of the photoconductive material in conveyance. The back electrode comes into contact with the back surface of the photoconductive material, whereas the developing electrode is spaced part from the photoconductive layer. Upon directly connecting the electrodes, toner particles contained in the developing solution adhere to the photoconductive layer to achieve development. The developing electrode does not touch the photoconductive layer, making a developed image free from soiling, the electrodes are immersed in the developing solution, preventing the drying and solidifying of the solution around the electrodes, and the developing tank is covered with a lid, preventing the vaporizing of the developing solution.

Liquid electrophotographic developing device

A liquid electrophotographic development method where electrodes are arranged only on the side of the photosensitive layer of a master, developing liquid is supplied between the master and the electrodes, and conductors are made to come into contact with the base of the master so that an electric field is generated between the photosensitive plane and the electrodes for development. The electrode to be used for the electrophotographic development method includes conductive wires of a plural number which are arranged in the direction perpendicular to the traveling direction of the material so as to come into contact with the conductive base thereof. If the electrodes are utilized, a main electrode needs to be arranged only on the side of the photosensitive layer of the master, and developing liquid is supplied therebetween. The electrode is adapted to come into contact with the conductive base of the master, to thereby generate an electric field between the main electrode and the electrode. Therefore, the master can be directly injected with electrons instead of indirect injection, and adhesion of toner scum which often was caused in the prior art can be avoided. This further eliminates the trouble of cleaning the electrodes to improve maintenance.

Liquid developing method and apparatus for electrophotography, and

An electrophotographic lithographic printing plate precursor which is suitable for not only the ordinary developing methods but also the developing methods of direct electron injection system and which after developing, can readily be wound and fixed, as a lithographic printing plate, around a drum of a printing machine without any slippage after winding is provided. This precursor comprise a base of paper coated, on both surfaces thereof, with .alpha.-polyolefin laminated layers each having a volume resistivity of at most 1.times.10.sup.10 .OMEGA. and being further provided, on one side thereof, with a photoconductive layer and on the other side thereof, with an over back layer having a surface resistivity of at most 1.times.10.sup.10 .OMEGA. and a larger friction coefficient than the .alpha.-polyolefin laminated layer.

Electrophotographic lithographic printing plate precursor with over back

An electrophotographic lithographic printing plate precursor capable of giving a good image free from pinholes is provided which comprises an electrically conductive base coated, on one side thereof, with an undercoated layer and a photoconductive layer containing zinc oxide as a predominant component in order and on the opposite side thereof, with a back layer, said undercoated layer having a surface resistivity of 1.times.10.sup.8 to 1.times.10.sup.14 .OMEGA. and said back layer having a surface resistivity of at most 1.times.10.sup.10 .OMEGA..

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Shizuoka, Japan

Chiaki Kawamoto