Ink, recording method, recording unit, ink cartridge, and recording apparatus
US7025817B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 7, 2005 |
| Grant date | Apr 11, 2006 |
| Priority date | — |
| Expiry date | Feb 7, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D11/30
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An ink-jet ink comprises water, a water-soluble coloring material having a molecular weight of 600 or less as a free acid form, at least two kinds of water-soluble organic solvents, and urea or a derivative thereof. The vapor pressures at 25° C. of the at least two kinds of water-soluble organic solvents are lower than that of water. The water-soluble organic solvents include a water-soluble organic solvent A and a water-soluble organic solvent B. The solubility of the water-soluble coloring material in the water-soluble organic solvent A is higher than its solubility in water, while its solubility in the water-soluble organic solvent B is equal to or lower than its solubility in water. The difference between the solubilities of the water-soluble coloring material in the water-soluble organic solvent A and in the water-soluble organic solvent B is 10% or more. The ink-jet ink does not cause clogging of an ejection portion nor deposition of a coloring material and is capable of providing good print quality even after leaving a printed image for a long term under high temperature and humidity conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.