METHOD FOR PREPARATION OF POLYMER ACETAL-BASED DISSOLUTION INHIBITOR, DISSOLUTION INHIBITOR OBTAINED THEREBY, AND POSITIVE CHEMICAL SENSITIZATION PHOTOSENSITIVE RESIN COMPOSITION

摘要

PROBLEM TO BE SOLVED: To provide a polymer acetal-based dissolution inhibitor having an excellent shelf-stability which is used as a chemical sensitization positive resist exerting a high sensitivity and a high resolution, and a chemical sensitization positive photosensitive resin composition using the dissolution inhibitor. SOLUTION: The preparation process of a polymer acetal-based dissolution inhibitor having a structure of the formula (wherein R1 is hydrogen atom or a 1-6C linear, branched or cyclic alkyl group; R2 is a 1-10C linear, branched or cyclic alkyl group; R1 and R2 may be linked together to form a 2-5C methylene chain; and m and n are each a natural number satisfying the formulae: 0.4<=m/(m+n)<=1.0 and 10<=m+n<=200) comprises a purification step wherein a reaction product is dissolved in an organic solvent which has a boiling point of 120 deg.C or higher and does not have any alcoholic hydroxyl group within the molecular structure, and subsequently distilled or vacuum distilled to remote impurities and water.