| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new copolycarbonate excellent in processability, low in orientation birefringence, low in glass transion temperature, and useful for production of optical discs. SOLUTION: This copolycarbonate consists of (A) 20-90mol% of a structural unit expressed by formula I, (B) 3-70mol% of a structural unit expressed by formula II [R<1> is an alkyleneoxy or m-phenyleneoxy, or a group of formula III [(n) is 4-25] or formula IV (R<2> is a 2-6C alkylene, etc.; R<3> is a 1-4C alkyl, etc.; (m) is 0-2)] and optionally, (C) a structural unit expressed by formula V [A<1> and A<2> are each (substituted) m- or p-phenylene; Y is a single bond or a linkage group). The structural unit A is derived from 1,1,3-trimethyl-3-(4- hydroxyphenyl)-5-hydroxyindane, etc. The structural unit B is a resorcinol carbonate unit, etc. The structural unit C is preferably a bisphenol A carbonate unit. The above copolycarbonate can be produced by a conventional polymerization method, such as interfacial polymerization, transesterification, redistribution or solid-phase polymelization method. |
