Optical disc and prodn. esp. small scale prodn. of audio-visual disc - by laser exposure of photoresist contg. resin, light-sensitive cpd. and ballast cpd.

摘要

Prodn. of optical discs involves (a) exposure of a photoresist coat (I) on a transparent substrate with a focussed laser beam, using (I) contg. a resin (II), a light-sensitive material (III) and a ballast cpd. (IV); (b) development to form very small pits in the surface of (I); (c) baking to fix (I); (d) UV exposure; and then either (e-1) coating with a reflective film and forming a protective film on the reflective film; or (e-2) transferring a transparent coat of UV-curable resin to the surface. Pref. (II) are cresol novolak resins; (III) esters of 1,2-naphthoquinone-diazo-5-sulphonyl chloride; and (IV) bis(hydroxyaryl) or aryl hydroxyaryl ketones, alkyl gallates, N-alkyl-gallamide and bisphenols. USE/ADVANTAGE - The process is relatively simple, reduces the number of prodn. stages and increases the life of the discs. It is suitable for making many types of optical discs, both in mass prodn. and esp. in small-scale prodn. e.g. of audio-visual software.