Heat sensitive system and use thereof
US5427415A · kind A · utility
73Cited by
20References
39Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 9, 1992 |
| Grant date | Jun 27, 1995 |
| Priority date | — |
| Expiry date | Dec 9, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S283/904
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A heat sensitive system comprises a document having a localized, non-pressure sensitive, coating of chromogenic composition activated at moderate temperatures. Quickly striking the chromogenic composition with a fingernail or blunt object produces a colored image by frictional heat. The chromogenic composition contains a chromogenic compound and a color developer which are non-pressure sensitive and non-reactive at room temperature. The chromogenic composition can be an intimate mixture of the chromogenic compound and the developer or alternatively separate layers of each of the components.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.