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. 02, 1990
Filed:
Oct. 29, 1987
Alan L Borror, Andover, MA (US);
Ernest W Ellis, Carlisle, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
A thermal imaging method is provided which comprises heating imagewise a di- or triarylmethane compound possessing within its di- or triarylmethane structure an aryl group substituted in the ortho position to the meso carbon atom with a moiety ring-closed on the meso carbon atom directly through a nitrogen atom, which nitrogen atom is also bound to a group with a masked acyl substituent that undergoes fragmentation upon heating to liberate the acyl group for effecting intramolecular acylation of said nitrogen atom to form a new group in the ortho position whereby the di- or triarylmethane compound is rendered colored in an imagewise pattern corresponding to said imagewise heating.