Pressure-sensitive record material
US4275905A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 5, 1979 |
| Grant date | Jun 30, 1981 |
| Priority date | — |
| Expiry date | Jun 5, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S428/914
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A substantially colorless marking liquid, particularly for use in pressure-sensitive record material, comprising (a) a colorless chromogenic material, (b) a solvent for said chromogenic material and (c) an additive for controlling CB decline. The additive for controlling CB decline, i.e., controlling the capability of the CB sheet to produce an image of satisfactory intensity even after exposure of the CB coating to light, includes certain chromogenic materials such as Pyridyl Blue and phenol derivatives having a free reactive (ortho- or para-) position. The marking liquid helps to prevent CB decline in, for example, carbonless copy paper, a long-standing problem in the art.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.