Thermochromic ink composition
US6413305B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 2000 |
| Grant date | Jul 2, 2002 |
| Priority date | — |
| Expiry date | Feb 7, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24802
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A thermochromic ink composition is provided for use on security documents such as checks which provides a reversible color change in response to heat. The ink composition includes a thermochromic aqueous slurry and an ink vehicle comprising either a phenolic modified rosin and a compatible oil, a styrene maleic anhydride resin and a glycol, or an acrylic resin varnish. The ink composition is printed on at least a portion of a substrate using letterpress printing methods and provides enhanced adhesion to toner when applied to areas of a substrate which are subsequently printed with a non-impact printing device such as a laser printer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.