Abstract
The cycloolefin resins are amorphous transparent resins which have a good optical properties and heat resistance. Therefore they attract attentions very much because the demands of downsizing, weight reduction, high performance and cost down to optical components are recently expanding. Conventional optical resins : Polymethylmethacrylate (PMMA) and Polycarbonate (PC) are known well. But they have the polar functional groups leading to high water absorption properties and property change due to environmental change. In addition, refractive index of PMMA is low and birefringence of PC is high. The cycloolefin resins are the resins which can solve the problems of PMMA and PC by introducing the cycloolefin unit to polyolefin. APELTM is the cycloolefin copolymer (COC) developed by Mitsui Chemicals, Inc. This resin has a superior optical properties : high refractive index and low birefringence and has a superiority among same kinds of cycloolefin resins. We explain about the structure, properties and applications of APELTM.
