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:
Aug. 11, 1987
Filed:
Sep. 05, 1984
Applicant:
Inventors:
Harold H Heller, Cardiff, GB;
Stephen N Oliver, Mid-Glamorgan, GB;
John Whittal, Mid-Glamorgan, GB;
William Johncock, Geneva, CH;
Paul J Darcy, Aberystwyth, GB;
Clive Trundle, Towcester, GB;
Assignee:
The Plessey Company P.L.C., Essex, GB;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ; C09K / ; G03C / ;
U.S. Cl.
CPC ...
351163 ; 351 44 ; 351166 ; 350586 ; 549 41 ; 549 42 ; 549 44 ; 549 60 ; 548407 ; 252586 ;
Abstract
A series of photochromic compounds are disclosed which have the property of undergoing a reversible color change when exposed to unfiltered sunlight and reverting to their original color in the absence of U.V. light at room temperature. These compounds have the general formula: ##STR1## represents an adamantylidene or a substituted adamantylidene group;