| 摘要 |
PURPOSE:To improve reproducibility of images and to obviate generation of registration defects in transfer of the multicolor images by forming the protective film of an image forming material in such a manner that this film satisfies specific conditions. CONSTITUTION:The deviation length E of the protective film is set at E=1E'1-E'n1<=0.1 when this length is E'1 to E'n with n-sheets of the protective films, where E'1, E'n are made plus when the coefft. of thermal expansion on a +45 deg. direction side is larger than the coefft. of thermal expansion of the -45 deg. direction side and is made minus when the coefft. of thermal expansion on the -45 deg. direction side is larger than the coefft. of thermal expansion of the +45 deg. direction side. The deviation length E' in the axial line direction of the impression cylinder is expressed by E'= LXaXDELTATX(F-1), where DELTAT is a difference between the temp. at the time of exposing the number of the image forming materials and a temp. when the image forming material is affixed to the impression cylinder; (a) is smaller of the coeffts. of thermal expansion of the direction which is viewed from the nipping side of the image forming material and is the +45 deg. or -45 deg. with the circumferential direction of the impression cylinder; F is a value obtd. by dividing the larger of the coeffts. of thermal expansion described above by (a); L is the length in the circumferential direction of the impression cylinder of the printing surface, respectively. |
