| 摘要 |
PURPOSE:To prevent emulsification at the time of offset printing by using an ammonium salt of a styrene/maleic anhydride ester copolymer esterified by isobutyl alcohol or butyl cellosolve in a protective layer. CONSTITUTION:A thermal color forming layer containing at least one kind of a basic dye and a developer capable of developing a color upon the contact with the basic dye is provided on a support and a protective layer based on polyvinyl alcohol and/or a modified substance thereof is provided thereon and 3-30wt.% of an ammonium salt of a styrene/maleic anhydride ester copolymer esterified by isobutyl alcohol or butyl cellosolve so that a degree of esterification becomes 60% or more is contained in the protective layer and a crosslinking agent is also contained therein. BY this method, the generation of emulsification phenomenon at the time of offset printing is prevented to make it possible to enhance printability. |
