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:
Jan. 07, 1986
Filed:
Oct. 18, 1984
Harvey A Brown, Lake Elmo, MN (US);
Louis M Leichter, Woodbury, MN (US);
Alan G Miller, St. Paul, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
Thermographic composition comprising a leuco dye, a nitrate salt, and, optionally, an acid and stabilizing compound. The leuco dye contains a phenazine nucleus with naphthoyl substitutents on the 10-position and, optionally on one or both of the 3- and 7-positions through an amino group. In their oxidized form, the leuco dyes of this invention provide access to a range of red and magenta colors which exhibit greater stability when subjected to light and temperatures characteristic of the stage of overhead projectors than that exhibited by previously available leuco dyes of this color range.