Abstract: A water base ink for ink-jet recording contains a self-dispersing type pigment, glycol ether, and water. In the glycol ether, the number of carbon atoms of an ethylene oxide moiety is not less than 8, and the solubility in water at 25° C. is not less than 1%. The ink reduces the blurring of a recorded image which would be otherwise caused by the feathering on the paper surface. The ink is excellent in drying performance on the paper surface, and the ink makes it possible to stably disperse the pigment.

Abstract: A water base ink for ink-jet recording, which is usable for an ink-jet recording apparatus having an ink-jet head provided therein with an ink flow passage formed of nickel or nickel alloy, comprises a coloring agent, water, and a water-soluble organic solvent. The ink is blended so that a current density, which is obtained within an electric potential range of −600 to +300 mV, is not more than 100 &mgr;A/cm2 when anodic polarization measurement is performed by using a reference electrode of silver/silver chloride, a counter electrode of platinum, and a working electrode of nickel or nickel alloy. The ink does not corrode any part for constituting the flow passage in the ink-jet head.

Abstract: A hot melt ink includes at least one wax, at least one coloring material, a first resin having a softening point ranging from room temperatures to 100.degree. C., and a second resin having a softening point ranging from 50.degree. C. to 150.degree. C. and higher than the softening point of the first resin. The hot melt ink has an appropriate softening point and high light transmittance while maintaining fixing property and appropriate viscosity by combining a resin with a relatively low molecular weight and a resin with a relatively high molecular weight.