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. 11, 1993
Filed:
Nov. 20, 1991
Applicant:
Inventors:
Rita S Shon Baker, Brookline, MA (US);
Larry C Takiff, Arlington, MA (US);
Assignee:
Polaroid Corporation, Cambridge, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B41M / ;
U.S. Cl.
CPC ...
503201 ; 106 / ; 427151 ; 430200 ; 503202 ; 503204 ; 503209 ; 503218 ; 503221 ;
Abstract
The addition, to a thermal imaging medium comprising a color-forming compound which undergoes a change of color upon heating above a color-forming temperature for a color-forming time, the color-forming compound being of the cyclic sulfonamide type described in U.S. Pat. Nos. 4,720,449 and 4,960,901, of a quinone or hydroquinone increases the sensitivity of the imaging medium and helps to prevent fading of images produced therefrom while the images are being projected.