| 摘要 |
PURPOSE:To obtain a titled material having excellent hygroscopicity and hat resistance by using a copolymer of a methyl methacrylate and at least p-tert- butyl cyclohexyl methacrylate as a substrate material. CONSTITUTION:The methacrylic resin to be used is formed by copolymn. of p-tert-butyl cyclohexyl methacrylate and methyl methacrylate or copolymn. of p-tert-butyl cyclohexyl methacrylate, methyl methacrylate and the other monomer which can be copolymerized therewith. The ratio of both units in such methacrylic resin is in a 5:95-95:5 range, more preferably 10:90-60:40 and the more preferable ratio is in a 15:85-50:50 range based on polymn. |
