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. 08, 2009
Filed:
Mar. 21, 2007
Tsuyoshi Kawai, Ikoma, JP;
Takuya Nakajima, Ikoma, JP;
Shigekazu Kawai, Ikoma, JP;
Abstract
The present invention provides a photochromic compound that is colored when irradiated with visible light and quickly faded when set in a dark place. The photochromic compound according to the present invention is expressed by the following general formula (I): where each of A, Aand Ais a five-member rings forming a 6π-electron system, the three rings being identical, partially identical or totally different from each other, and each ring may have a substituent; Band Bare functional groups, each having an atomic number of five or larger, including a ring compound, and bonded to the 2-carbon of each of Aand A, respectively; and R, Rand Rare substituents identical to or different from each other. This compound is highly colorable and durable even when it is dispersed into plastic macromolecular materials. Therefore, it is suitable as a dye material for sunglasses or similar products.