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:
Dec. 20, 1994
Filed:
Mar. 29, 1993
Shinichi Yamamoto, Kyoto, JP;
Takashi Taniguchi, Shiga, JP;
Toray Industries, Inc., Tokyo, JP;
Abstract
A spiro-oxazine compound represented by the following general formula (A) or (A') is a photochromic compound having an excellent fatigue resistance to repetition of coloration and decoloration and an abundance of hues: ##STR1## wherein the .alpha. ring is a ring selected from a 5-membered ring having one N atom, which may be connected to a benzene ring or naphthalene ring, and a 6-membered ring having one N atom, with the proviso that the N atom in the .alpha.ring is bonded to a C.sub.1-20 alkyl or another organic group, X is selected from O, S, Se and N--R.sup.1 (in which R.sup.1 is selected from H, and C.sub.1-20 alkyl and other organic groups), R.sup.2 and R.sup.3 are selected from --OH, amino, C.sub.1-20 alkoxy, halogen, and other groups, and k is an integer of 0 to 2.