Aqueous ink, ink-jet recording method, ink cartridge, recording unit, ink-jet recording apparatus and image forming method
US7276112B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 2005 |
| Grant date | Oct 2, 2007 |
| Priority date | — |
| Expiry date | Dec 22, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D11/326
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Disclosed is an aqueous ink comprising at least water, a plurality of water-soluble organic solvents and a coloring material. The coloring material is a pigment, and, it contains a pigment particle having at least one ionic group bonded to a surface of the pigment particle directly or via another atomic group. The plurality of water-soluble organic solvents have a good medium or good mediums for the pigment and a poor medium or poor mediums for the pigment. The poor medium does not solvate perfectly or substantially the pigment. The ionic group undergoes perfectly or substantially no ionic dissociation in the poor medium. Also, among the respective Ka values of the plurality of water-soluble organic solvents as determined by the Bristow method, the Ka value of the poor medium is maximum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.