Black-to-color bleed alleviation using non-specific ionic, pH, and colloidal effects
US5853465A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 24, 1997 |
| Grant date | Dec 29, 1998 |
| Priority date | — |
| Expiry date | Mar 24, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41J2/01
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An ink-jet ink set comprises (a) a microemulsion-based black ink in which the colorant is a water-insoluble black pigment has been chemically modified to impart water solubility by addition of functional groups to form a macromolecular chromophore and (b) at least one non-black (cyan, yellow, or magenta) ink that is a typical aqueous dye-based ink with an agent that increases the ionic strength of the no-black ink and comprises either an inorganic salt or an organic acid; the organic acid is used to adjust the pH of the non-black ink to a value of less than 5. The non-black ink may alternatively comprise a water-insoluble non-black pigment that has also been chemically modified. The macromolecular chromophore-containing ink, or pigment-based ink, of the ink-jet ink set is a microemulsion that contains a substantially water-insoluble organic oil, an organic co-solvent, and water and, optionally, an amphiphile and a high molecular weight colloid. By employing an ink set in which some of the members of the set have a higher ionic strength than the black, microemulsion-based ink, then bleed alleviation can be achieved. When the higher ionic strength ink comes in contact with the lower …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.