| abstract |
PROBLEM TO BE SOLVED: To provide a polymer having high photosensitivity, excellent adhesiveness to an aluminum substrate, and high printing continuity stability. A composition which suffices as few components as possible (preferable in terms of economy) as compared to compositions known in the state of the art and which has an equivalent or partially improved performance. To provide a polymer. SOLUTION: A polyvinyl acetal copolymer obtained by simultaneously reacting at least two kinds of aldehydes with polyvinyl alcohol having a number average molecular weight of 20,000 to 150,000 g / mol. |