Document Type and Number:
Japanese Patent JPH0526258
Kind Code:
B2
Abstract:
1. Process for producing improved optically readable information storage plates having greater dimensional stability and accuracy of measurement from optically transparent polymethylmethacrylate, the information storage plates containing the optically readable information fixed on one or two intermediate layers parallel to the surface of the plate, by joining together two panes which are approximately half as thick as the finished storage plate, characterised in that, during the original shaping and subsequent machining steps, the formation of a moisture gradient over the thickness and diameter of the plates is minimised.
Inventors:
YUURUGEN HENITSUHI
HAINTSU FUETAA
MANFUREETO BUTSUKU
HAINTSU FUETAA
MANFUREETO BUTSUKU
Application Number:
JP11544881A
Publication Date:
April 15, 1993
Filing Date:
July 24, 1981
Export Citation:
Assignee:
ROEHM GMBH
International Classes:
B29D17/00; B29C61/00; B29C69/00; G11B3/70; G11B7/24; G11B7/26
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