| 摘要 |
PURPOSE:To minimize the deterioration of while turbidity, if a process 'imaging- deletion' is repeated using a heating device such as a thermal head by providing the first thermal layer consisting mainly of resin at a specific value of glass transmission temperature as a resin material near a support and the thermal layer consisting mainly of resin at a specific value of glass transition temperature as a resin material on the former. CONSTITUTION:The glass transition temperature of a resin material is allowed to increase from 80 deg.C or lower to 80 deg.C or higher gradually in proportion to a s distance between a support side and a free surface side or a protection layer side. In this case, the two-layer structure type gives the most satisfactory results. The recommended resins at a glass transition temperature of 80 deg.C or lower used for the first thermal layer laminated over a transparent support such as sheet glass are a copolymer of vinyl chloride-vinyl acetate. On the other hand, the recommended resin materials at a glass transition temperature which is laminated over the first thermal layer are such as high transparency, good mechanical stability and excellent film formation properties. For example, aromatic diol is used instead of glycol and diol is allowed to undergo a chemical reaction with ester dicarboxylate to obtain polyester. In addition, many benzene rings are added to the material. |
