Thermal imaging methods and materials

US5350870A · kind A · utility

Assignee

• Polaroid Corporation · US

Inventors

• Roger A. Boggs · Wayland, US
• Richard L. Cournoyer · San Francisco, US
• Ernest W. Ellis · Harvard, US
• Sandra E. Russo-Rodriguez · Englewood, US
• Stephen J. Telfer · Arlington, US
• David P. Waller · Lexington, US
• Michael J. Zuraw · Arlington, US

Key dates

• Filing date: Apr 12, 1993
• Grant date: Sep 27, 1994
• Expiry date: Apr 12, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09B55/009
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Leuco dyes are provided which comprise the coupling product of a N-acyl substituted aromatic amino color developer and a dye-forming coupler moiety substituted at the coupling carbon with a thermally removable leaving group. Thermal imaging systems employing these leuco dyes have the advantage of reduced bubble formation relative to thermal imaging systems employing prior art leuco dyes containing a group which thermally fragments into one or more gases.