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. 03, 1999
Filed:
Apr. 30, 1998
Applicant:
Inventors:
Assignee:
Tokuyama Corporation, Tokuyama, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ; C07D / ; C07D / ;
U.S. Cl.
CPC ...
544 60 ; 544 62 ; 544375 ; 544376 ; 546112 ; 546164 ; 546269 ; 548454 ; 548511 ; 549389 ;
Abstract
The present invention relates to a novel chromene compound having favorable photochromic properties, developing a color of a high density, exhibiting a small degree of initial color and permitting the color to quickly fade. The novel chromene compound has an amino group that may be substituted for a sixth position of a naphthopiran ring, has electron-donating groups at para-positions of the two phenyl groups bonded to the third position, and has at least one or more electron-attracting groups at meta-positions of the phenyl groups, and is represented, for example, by the following formula, ##STR1##