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:
Oct. 31, 2000
Filed:
Jun. 11, 1999
Applicant:
Inventors:
Assignee:
Tokuyama Corporation, Yamaguchi-ken, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ;
U.S. Cl.
CPC ...
359241 ; 359245 ; 359246 ;
Abstract
A photochromic composition which develops a neutral tint such as grey, green, brown or amber upon the irradiation with light including ultraviolet rays such as sunlight starting from the initial colorless state, maintaining a homogeneous color tone in the transient stage of developing color. The photochromic composition comprises 100 parts by weight of a fulgimide compound and/or a fulgide compound, and from 10 to 300 parts by weight of a chromene compound having a molar extinction coefficient of not smaller than 150 L/mol-cm for light of a wavelength of 400 nm.