POLYVINYL ACETAL RESIN FOR HEAT-DEVELOPABLE PHOTOSENSITIVE MATERIAL AND HEAT-DEVELOPABLE PHOTOSENSITIVE MATERIAL
申请人:SEKISUI CHEMICAL CO., LTD.
公开号:EP1270608A1
公开(公告)日:2003-01-02
The present invention has an object
to provide a polyvinyl acetal resin for heat-developable photosensitive materials as well as a heat-developable photosensitive material while solving such problems as coating solution pot life, coloration of heat-developable photosensitive material, fog, poor gradation, insufficient sensitivity and poor undeveloped film storability and making it possible for the materials to acquire good image characteristics.
The present invention is constituted of a polyvinyl acetal resin for heat-developable photosensitive materials
which is a polyvinyl acetal resin synthesized by the acetalization reaction between a polyvinyl alcohol and an aldehyde and
which comprises having a degree of polymerization of 200 to 3, 000, a residual acetyl group content of 0 to 25 mole percent and a residual hydroxyl group content of 17 to 35 mole percent, as calculated while regarding one acetal group as two acetalized hydroxyl groups, a water content of not more than 2.5% by weight and a residual aldehyde content of not more than 10 ppm and is free of any antioxidant.
本发明的目的是
提供一种用于热显影感光材料的聚乙烯醇缩醛树脂以及一种热显影感光材料,同时解决涂层溶液的罐装寿命、热显影感光材料的着色、雾化、色阶差、感光度不足和未显影胶片的耐储存性差等问题,并使材料获得良好的图像特性成为可能。
本发明由用于热显影感光材料的聚乙烯醇缩醛树脂构成
它是由聚乙烯醇和醛之间的缩醛反应合成的聚乙烯醇缩醛树脂,并且
其聚合度为 200 至 3,000,残余乙酰基含量为 0 至 25 摩尔%,残余羟基含量为 17 至 35 摩尔%(计算时将一个缩醛基视为两个缩醛羟基),水含量不超过 2.5%(重量百分比),残余醛含量不超过 10 ppm,且不含任何抗氧化剂。