Patent · US Expired

Thermally-responsive record material

US4820683A · kind A · utility

16Cited by
13References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 4, 1987
Grant dateApr 11, 1989
Priority date
Expiry dateDec 4, 2007

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S428/913
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

An improved thermally-responsive record material having improved image retention is disclosed. The invention is an improved thermally-responsive record member, typically a sheet material, bearing a thermally-responsive color-forming composition comprising a chromogenic material, an acidic developer material, and a metal salt of a compound of the formula ##STR1## wherein R.sup.a is selected from --CH.dbd.CH, ##STR2## --(CH.sub.2).sub.4 --, --(CH.sub.2).sub.3 --, --(CH.sub.2).sub.3 --, --CH.sub.2 --CH.dbd.CH--, and --CH.sub.2 --wherein R.sub.1 is selected from hydrogen, halogen, alkyl, oxyalkyl, or NO.sub.2 with the proviso that the alkyl groups are of 1-5 carbons wherein M is a metal selected from Zn, Ca, Sn, Ni, Cu, Al, Co, and Mg.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.