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:
Sep. 21, 1993
Filed:
Mar. 28, 1991
Kayo Iwamoto, Shin-nanyo, JP;
Takashi Tanaka, Shin-nanyo, JP;
Satoshi Imura, Tokuyama, JP;
Seiji Okazaki, Tokuyama, JP;
Shinsuke Tanaka, Tokuyama, JP;
Tokuyama Soda Kabishiki Kaisha, Tokuyama, JP;
Abstract
A photochromic compound of the present invention is a spiroxazine compound represented by the following formula: ##STR1## wherein R.sup.1 to R.sup.3 represent a monovalent organic group such as alkyl group, Y represents a fused heterocyclic aromatic hydrocarbon group or an unsaturated heterocyclic group if R.sup.1 and R.sup.2 are both methyl groups, and represents an aromatic hydrocarbon group or unsaturated heterocyclic group if R.sup.1 and R.sup.2 are other than the above mentioned. This compound shows an excellent photochromic characteristics even at high temperatures not less than ambient temperature.