The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 21, 1977
Filed:
Jul. 07, 1975
Kurt-Rainer Stahlke, Krefeld, DT;
Werner Krafft, Leverkusen, DT;
Rudolf Meyer, Leverkusen, DT;
Hans Jurgen Rosenkranz, Krefeld, DT;
AGFA-Gevaert, A.G., Leverkusen, DT;
Abstract
A storage medium for optical data recording comprises a dye-forming combination which on exposure to light within a first range of wavelengths reacts irreversibly to form a dye, but is substantially insensitive to light within a second range of wavelengths which is capable of energizing the dye to produce luminescence. The dye-forming combination consists of a heterocyclic compound of the formula I and of a cyclic dihalodicarbonyl compound of the formula II ##STR1## The symbols are defined in the specification. An example of formula I is benzofuran and an example of formula II is dibromomaleic anhydride.