Patent · US Expired

Thermochromic materials

US4028118A · kind A · utility

183Cited by
2References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1975
Grant dateJun 7, 1977
Priority date
Expiry dateDec 23, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/24835
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

An excellent thermochromic material exhibiting a sharp and reversible metachromatism at temperatures within a range of from -40.degree. to 80.degree. C can be formed from (A) an electron-donating, chromatic organic compound; (B) a compound containing a phenolic hydroxyl group; (C) a compound selected from the group consisting of higher aliphatic monovalent alcohols; and (D) a compound selected from the group consisting of higher aliphatic monovalent acid alcohol esters. The excellent thermochromic characteristics of such a thermochromic material can be further improved when it is occluded in fine microcapsules having a size not exceeding 50 .mu.. Thermochromic polymers, thermochromic printing inks, thermochromic writing instruments, thermochromic paints and thermochromic sheets having excellent thermochromatic characteristics and wide utility can be prepared from such a thermochromic material or microencapsulated thermochromic material.

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