PURPOSE: To obtain an oxygen-permeable material suitable for hard contact lenses, etc., and excellent in wearability, stain resistance and biocompatibility, formed from a fluorinated copolymer obtained by copolymerizing a specified fluorinated cycloolefin with a fluorinated (meth)acrylate ester monomer.
CONSTITUTION: A fluorinated copolymer is obtained by polymerizing 2W50wt.% fluorinated cycloolefin (a) of formula I (wherein AWC are each H, F or a hydrocarbon group, D is an F atom or a 1W30C fluorinated hydrocarbon group which may contain an O atom and to which at least one F atom is bonded and n is 0W2), 98W50wt.% fluorinated (meth)acrylate (b) of formula II (wherein Rf is a 1W30C fluorinated hydrocarbon group which may contain an O atom and to which at least three F atoms are bonded, R1 is H or CH3 and m is 0W4), and, optionally, another comonomer (c) at any desired ratio at 40W200°C for 0.5W5,000min in the presence of a thermal polymerization radical initiator (d) such as azobisisobutyronitrile. This copolymer is molded into any desired shape under melting conditions.
SHIMODA TOMOAKI
SUDO MASARU
TANAKA MASAHIDE
