Initially erasable ink composition for a ball point writing instrument
US4329262A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 25, 1981 |
| Grant date | May 11, 1982 |
| Priority date | — |
| Expiry date | Mar 25, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S260/38
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An initially erasable ink composition for a ball point writing instrument which ink is characterized by its initial erasability by ordinary pencil erasers when applied by a ball point writing instrument to an absorbent paper-like writing surface and which thereafter develops permanence. The ink composition comprises an elastomer selected from the group consisting of natural rubbers, synthetic rubbers and mixtures thereof, pigment, and a solvent system for said elastomer and pigment. The elastomer is present in the range of about 18-28% by weight of the ink and the pigment is present in the range of about 10-22% by weight of the ink. The solvent system comprises a volatile component present in the range of about 8-30% by weight of the ink and having a boiling point less than about 180.degree. C. and an essentially non-volatile component which is predominantly a low viscosity hydrocarbon oil, essential oil, petroleum derivative, plasticizer or mixtures thereof having a boiling point less than about 300.degree. C. and greater than about 180.degree. C. being present in the range of about 21 to 50.5% by weight of the ink. The solvent system may also include up to 15% by weight of the in…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.