Patent ID: 7824028

Claim:
A method for selecting a combination of water-based ink and wetting solution for ink-jet recording, comprising: dipping one end of a capillary having an inner diameter of from about 0.1 to about 1 mm in a water-based ink, wherein an inner wall of the capillary is dry and the water-based ink rises inside the capillary, and measuring Vs, dipping one end of the capillary in the water-based ink, wherein an inner wall of the capillary is wetted with a wetting solution and the water-based ink rises inside the capillary, and measuring Vi, and selecting a combination of the water-based ink and the wetting solution if the combination satisfies the following formula (1): Vi/Vs≧ 2 (1) Wherein: i) Vs indicates a rising speed of water-based ink at an intermediate position before and after rising when the inner wall of the first capillary is dry, and ii) Vi indicates a rising speed, of water-based ink at an intermediate position before and after rising when the inner wall of the second capillary is wetted with the wetting solution; wherein the intermediate position corresponds to a volume (A) of water-based ink of about 1 to about 4 μl.