PURPOSE: To compose a direct offset printing plate from the digital data of a computer by providing resin not dissolved in water on a board, superposing a plate sheet graft-polymerized with hydrophilic monomer on the surface of the resin and a transfer sheet provided with a transfer layer containing hydrophobic thermoplastic resin on the board thereby, heating it and transferring the layer partly onto the plate sheet.

CONSTITUTION: Sheet, a metal plate, a plastic sheet, etc., may be used as a board. As resin not dissolved in wafer, epoxy resin is preferably employed, and as hydrophilic monomer, acrylamide is preferably employed. A grafting method is conducted by applying energy such as heat, light, electron beam or the like. As hydrophobic thermoplastic resin, epoxy resin, polyester resin, etc., are employed solely or in combination. In order to form an image of a transfer layer on a plate sheet, the plate sheet and a transfer sheet are superposed with the board at the outside, heated in an image state from the side of the transfer sheet, thereby partly transferring the transfer layer onto the plate sheet.