Patent ID: 6165549
Filing Date: 2000-12-26
Classification: B05D,C08F

Abstract:
A process for producing a solvent-free acrylic sheet, comprising:a coating step comprising either coating at least one support with a solvent-free syrupy composition for coating polymerization or applying the solvent-free coating polymerization syrupy composition between at least two supports at a coating thickness of at least 0.15 mm to thereby form a laminate, said solvent-free coating polymerization syrupy composition comprising an acrylic vinyl monomer capable of radical polymerization, at least one member selected from the group consisting of an acrylic vinyl monomer partial polymerizate and a polymer including a unit derived from an acrylic vinyl monomer, a low-temperature decomposable polymerization initiator having a 10 hr half-life temperature ranging from 25.degree. to 55.degree. C. and a high-temperature decomposable polymerization initiator having a 10 hr half-life temperature ranging from above 55.degree. to 90.degree. C., said solvent-free coating polymerization syrupy composition having a viscosity ranging from 20 to 2000 poises at 25.degree. C., said solvent-free coating polymerization syrupy composition containing substantially no solvent;a heating polymerization step comprising heating the laminate at 60.degree. C. or higher for reaction initiation so that autoexotherm is induced to thereby cause the acrylic vinyl monomer capable of radical polymerization contained in the solvent-free coating polymerization syrupy composition to polymerize until the content of residual monomer in the solvent-free coating polymerization syrupy composition is in the range of 2 to 20% by weight based on the total weight of the solvent-free coating polymerization syrupy composition; andan aging polymerization step comprising maintaining the laminate having undergone the heating polymerization step at a temperature that is at least 30.degree. C. but lower than the heating temperature of the heating polymerization step so that a polymerization reaction is effected until the content of residual monomer in the laminate is 2% by weight or less based on the solvent-free coating polymerization syrupy composition.