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:
Mar. 06, 2001
Filed:
Feb. 19, 1999
Applicant:
Inventors:
Tsuneyoshi Tanizawa, Tokuyama, JP;
Tadashi Hara, Tokuyama, JP;
Yuichiro Kawabata, Tokuyama, JP;
Junji Momoda, Tokuyama, JP;
Hironobu Nagoh, Tokuyama, JP;
Assignee:
Tokuyama Corporation, Yamaguchi-ken, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 5/23 ; C07D / ;
U.S. Cl.
CPC ...
G02B 5/23 ; C07D / ;
Abstract
A photochromic compound featuring a large fading rate to prevent a change in the color tone at the time of fading, exhibiting little color after aged, and exhibiting good durability in the photochromic property. The photochromic compound is a novel chromene compound having a substituted phenyl group at the second position of the naphthopyrane ring and an alkyl group at the fifth position thereof, and is represented by, for example, the following formula,