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:
May. 18, 1993
Filed:
Jun. 17, 1991
Applicant:
Inventor:
Charles M Zepp, Berlin, MA (US);
Assignee:
Steadfast Inc., Cambridge, MA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F21V / ; C07D / ;
U.S. Cl.
CPC ...
252587 ; 544 73 ;
Abstract
A novel class of squarylium infrared absorbing dyes is disclosed which are prepared by the condensation of squaric acid with a benzoxazinone. The dyes are unique in that they possess the desirable properties of squarylium dyes in general along with a narrow band of peak absorbency greater than 1000. Because of their stability to laser beams, the dyes are particularly useful in ocular products for eye protection against lasers.