Sensitizer for heat sensitive paper coatings
US5066633A · kind A · utility
2Cited by
19References
23Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 9, 1990 |
| Grant date | Nov 19, 1991 |
| Priority date | — |
| Expiry date | Feb 9, 2010 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M5/327
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A heat sensitive coating has a colorless or light colored leuco dye precursor, preferably having a five-membered spirol lactone ring at one end of the molecule, and a tertiary amino group at another end of the molecule, and a developer. Sensitizers which increase the heat sensitivity of these dye precursors, and compositions of sensitized dye/developer systems are disclosed. The sensitizers are .gamma.-substituted lactones, 3-naphthylmethylidenephthalide, and derivatives of benzalphthalide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.