Mechanically erasable ballpoint ink
US5160369A · kind A · utility
11Cited by
4References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 21, 1991 |
| Grant date | Nov 3, 1992 |
| Priority date | — |
| Expiry date | Feb 21, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D11/18
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention provides ballpoint pen ink compositions containing carbon black which are initially erasable and require little or no external pressure for ink delivery. The ink can be erased easily with a normal rubber eraser such as that found on pencils. The ink compositions of the present invention comprises: about 15% to about 40% of an aliphatic hydrocarbon, about 15% to about 40% of an aromatic hydrocarbon, about 1% to about 15% of a colorant, about 4% to about 40% of one or more of a preselected thermoplastic block copolymer, and about 5% to about 40% of a preselected parting agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.