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:
May. 28, 1996
Filed:
Aug. 02, 1994
Applicant:
Inventors:
Martin Rickwood, Southport, GB;
Sean D Marsden, St. Helens, GB;
John D Hepworth, Preston, GB;
Christopher D Gabbutt, Blackburn, GB;
Assignee:
Pilkington PLC, , GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; C07D / ;
U.S. Cl.
CPC ...
252586 ; 549389 ;
Abstract
A naphthopyran compound of general formula (I) ##STR1## wherein R.sub.1 represents an alkyl group or an aryl group; each of R.sub.4 and R.sub.5, which may be the same or different, independently represents an alkyl, alkenyl, carbocyclic or heterocyclic group, or R.sub.4 and R.sub.5 taken together with the carbon atom to which they are attached form a carbocyclic ring or a heterocyclic ring; and
Rickwood, Martin. (1996). Photochromic compounds (U.S. Patent No. 5520853). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/5520853
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile