Writing liquid for use with an opaque recording material for forming transparencies for overhead projection and the like
US4327006A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 2, 1980 |
| Grant date | Apr 27, 1982 |
| Priority date | — |
| Expiry date | Sep 2, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M5/0029
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A writing liquid is formed from a solvent for an organic styrene resin pigment in combination with a chlorofluoroalkane of from 1 to 3 carbon atoms. The potential toxicity of the solvent (or solvent vapors) is eliminated and writing speeds of the writing liquid are improved by the addition of the chlorofluoroalkane. The writing liquid is used for transparentizing an opaque layer of an organic styrene resin pigment, uniformly distributed as fine particles in a film-forming binder carried on a transparent or opaque support. When the writing liquid is applied to the opaque layer using a suitable writing instrument, such as a pen, the opaque layer immediately becomes transparent where it is contacted with the solvent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.