| 摘要 |
PROBLEM TO BE SOLVED: To provide an offset printing method needing no alkaline developer, high in discriminating property between a picture part and a non-picture part, and capable of making a printed picture surface of excellent picture quality. SOLUTION: In this printing method, printing is performed by forming a printed surface with a picture region having accepted ink, by uniformly irradiating a printing plate with active light after a lipophilic picture is given to the printing plate having a thin layer of TiO2 , RTiO3 (R is an alkaline earth metal atom), AB2-x Cx D3-x Ex O10 (A stands for a hydrogen atom or an alkaline metal, B for an alkaline earth metal or a lead atom, C for a rare earth element, D for a metal of the fifth A group of the periodic system, E for a metal of the fourth A group thereof, and X for an arbitrary numerical value of 0 to 2), SnO2 , Bi2 O3 , ZnO, or Fe2 O3 , having nature of their surfaces being changed to have a hydrophilic property by irradiation of active light, and by removing the picture by water washing, or without removing it. |
