OPTICAL INFORMATION RECORDING CARD USING PHASE SEPARATION OF POLYMER BLEND

摘要

An information recording card using a semiconductor laser beam for writing and reading information. The card comprises a recording layer formed on one side of a card substrate and a light absorbing layer closely interposed between the substrate and the recording layer. The material of the recording layer is a polymer blend which comprises a copolymer of vinylidene fluoride and at least one F-containing comonomer, preferably hexafluoroacetone, and an acylic or methacylic ester polymer and which exhibits phase separation by heating. The light absorbing layer is for efficiently absorbing laser light used for recording and transforming it into heat energy. A good embodiment of the light absorbing layer is a film of Bi or Te, and another good embodiment is a thin layer of a resin composition containing fine particles of at least one of Bi, Te and C dispersed in a thermoplastic or thermosetting resin.