METHACRYLIC ACID ESTER POLYMER, METHOD FOR PRODUCING SAME, ACTIVE ENERGY RAY-CURABLE COMPOSITION, AND OPTICAL RECORDING MEDIUM

摘要

A cured product that is reduced in warping and has high hardness can be obtained from an active energy ray-curable resin composition which uses a methacrylic acid ester polymer that has an acid value of 50 mg KOH/g or less and a transition metal content of 1 ppm or less, while containing 80% by mole or more of a polymer that has a double bond-terminated structure represented by formula (1). (In formula (1), R represents an alkyl group, a cycloalkyl group or an aryl group.)