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.

Date of Patent:
Jan. 06, 1976

Filed:

Dec. 26, 1973
Applicant:
Inventors:

Alan L Borror, Lexington, MA (US);

Paulina P Garcia, Arlington, MA (US);

Assignee:

Polaroid Corporation, Cambridge, MA (US);

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
2603 / ;
Abstract

This invention relates to a new class of phthalein dyes useful as the color-forming material in either pressure sensitive or heat sensitive mark-forming systems. Such dyes comprise 3,3-disubstituted phthalides and 3,3-disubstituted naphthalides wherein the 3,3 substituents are indolin-5-yl radicals.


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