Pressure-sensitive recording material
US4147509A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 1978 |
| Grant date | Apr 3, 1979 |
| Priority date | — |
| Expiry date | Jan 9, 1998 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M5/15
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A pressure-sensitive recording material which comprises a substrate bearing a dye-forming component and a binder. The dye-forming component is a spirodipyran of the formula ##STR1## where A is the radical of a fused benzene or naphthalene ring (which rings may or may not be substituted), R.sup.1 is alkyl of 1 to 16 carbon atoms, substituted or unsubstituted phenyl or phenalkyl of 7 to 10 carbon atoms, R.sup.2 is H or together with R.sup.1 is a trimethylene or tetramethylene bridge which is unsubstituted or substituted by from 1 to 3 alkyl, R.sup.3 is benzyl or .beta.-phenylethyl and R.sup.4 is benzyl, .beta.-phenylethyl or substituted or unsubstituted phenyl, or R.sup.3 is alkyl of 1 to 4 carbon atoms and R.sup.4 is substituted or unsubstituted phenyl or R.sup.3 is benzyl and R.sup.4 is .beta.-cyanoethyl. The recording materials give violet to bluish green colorations (copies) only on paper coated with an electron acceptor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.