Ink composition
US5769931A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1996 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Jul 25, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D11/16
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Novel, improved ink compositions are aqueous-based, shock-resistant, shear-thinning inks for writing instruments having a shear index greater than 0.6. The inks are a substantially uniform dispersion including colorant(s), a water dispersible, polymeric shear-thinning material selected from the group consisting of welan gum, rhamsan gum and combinations thereof, and a substantially water-soluble polymeric viscosity modifier in a polar solvent system. While the ink compositions have a high viscosity at low shear rates, they undergo shear-thinning and are readily flowable in response to shear rates produced in writing to provide a writing ink having an especially desirable combination of performance characteristics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.