Odorless multi-valent metal modified products of salicyclic acid copolymers, production processes thereof, and use thereof as color-developing agents for pressure-sensitive copying paper sheets
US5028581A · kind A · utility
2Cited by
27References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 14, 1989 |
| Grant date | Jul 2, 1991 |
| Priority date | — |
| Expiry date | Aug 14, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M5/155
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Odorless or absolutely ordorless multi-valent metal-modified salicylic acid. The former copolymers are obtained by condensing salicylic acid with a benzyl aldehyde, reacting the resultant resin with a styrene derivative and reacting the resin thus-obtained with a multivalent metal salt. The latter copolymers are obtained by adding water dropwise to the resultant multi-valvent metal-modified resin at a temperature above the boiling point of water to remove completely volatile matters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.