PROCESS FOR THE PREPARATION OF NON-BIREFRINGENT OPTICAL RESIN AND OPTICAL ELEMENTS MADE BY USING THE RESIN PREPARED BY THE PROCESS

摘要

A process for the preparation of a non-birefringent optical resin, characterized by copolymerizing (A) 5 to 40 % by weight of a methacrylic or acrylic ester having a C5-C22 aliphatic hydrocarbon group in the ester moiety with (B) 50 to 80 % by weight of methyl methacrylate, (C) 5 to 40 % by weight of an N-substituted maleimide, (D) 0 to 30 % by weight of benzyl methacrylate, and (E) 0 to 10 % by weight of a monomer copolymerizable with these monomers at such a ratio as to give a resin having an absolute value of orientational birefringence of less than 1 x 10<-6>; and optical elements made by using the resin prepared by this process.