| 摘要 |
PROBLEM TO BE SOLVED: To provide a method which makes it possible to manufacture a cast molded article of an impact-resistant methacrylate resin, having sufficient impact resistance, a low residual monomer content, and higher transparency. SOLUTION: A composition is used which contains a monomer comprising mainly methyl methacrylate, a methacrylate resin comprising mainly methyl methacrylate units, (multilayer) elastic material particles, a first organic peroxide comprising a monofunctional organic peroxide having a 10-hr half-life temperature of 60°C or lower, a second organic peroxide comprising a monofunctional organic peroxide having a 10-hr half-life temperature of above 60°C to 80°C, and a third organic peroxide comprising a monofunctional organic peroxide having a 10-hr half-life temperature of above 80°C. The composition is polymerized by keeping it in a polymerization cell at a temperature, for example, lower than the 10-hr half-life temperature of the first organic peroxide by at least 10°C, and then raising the temperature to a temperature higher than the 10-hr half-life temperature of the third organic peroxide by at least 10°C. The obtained molded article is excellent in transparency and the like. COPYRIGHT: (C)2004,JPO |
