| abstract |
(57) [PROBLEMS] To provide a transparent PVA-based film which retains flexibility even after long-term use or under low temperature and low humidity and does not exude additive even under high temperature and high humidity. A PVA-based resin contains a compound represented by the following formula. In the formula, X is hydrogen or a hydroxyl group, and a, b, c and d are 0 ≤ It is an integer that satisfies a + b + c + d ≤6. |