PURPOSE: To uniformly and surely heat a printing plate with a heating plate without causing irregular heating while reducing the cost and improving the maintainability.

CONSTITUTION: Many pressing brushes 37 of a brush unit 35 come into contact with the printing plate 10 carried by a carrying roller 31, thereby, the printing plate 10 is brought into contact with a heating surface 33 with a specified pressure. Thus, the printing plate 10 is tightly brought into contact with the heating surface 33 of the heating plate 32 by the respective pressing brushes 37 while it is carried along the heating plate 32 in a carrying direction A, so that it is uniformly heated all over the surface with the heating plate 32.