PURPOSE: To obtain a disk free from deformation and pinhole by forming a curable resin layer consisting of a three-dimensionally curable resin on the surface of a disk base plate consisting of a thermoplastic resin and providing a thin film of SiO2 or Al2O3 thereon then forming a thin metallic film for information recording on said thin film.
CONSTITUTION: A soln. prepd. by dissolving epoxy, urethane and polysiloxane three-dimensionally curable preferably at the softening point or below of a base plate (may be a base plate formed with grooves in the position for information tracks) 1 obtd. by injection molding, etc. of a thermoplastic resin such as polymethyl methacrylate, etc., more particularly an epoxy acrylate resin, etc. curable by UV into a solvent which does not dissolve base plate is coated on said base plate and is cured to form a coating layer 2 having 1W30μ thickness. SiO2 or Al2O3 is then deposited by evaporation on the layer 2 to form a steam impermeable film 3 having 100W5,000 thickness. A thin metallic film 4 for recording consisting of Te, etc. is formed thereon. The plate 1 is thus prevented from deformation and pinhole in the stage of forming the film 4 and the film 4 is prevented from being oxidized and deteriorated by the moisture penetrated from the plate 1.
SUZUKI SETSUO
TANAKA JIYUNJI
Next Patent: DISK FOR INFORMATION RECORDING