To obtain a hot-melt ink excellent in dispersibility of a coloring matter and in hot-storage stability by compounding an organic substance having specified wt. average mol.wt. and acid value with a wax which is solid at normal temperature, a resin, and a pigment.
An organic substance having a wt. average mol.wt. of 600 or higher and an acid value of 60 or higher is used, examples being synthetic waxes such as an acid wax, a linear saturated linear carboxylic acid wax, a synthetic wax having acid groups, an acid-modified polyethylene wax, an α-olefin-maleic anhydride copolymer wax, a maleic acid wax, and an ethylene- propylene-maleic anhydride terpolymer. An oil-soluble resin is preferable as the resin. The amounts of the organic substance, the wax which is solid at normal temperature, the resin, and the pigment added are preferably 0.1-50 wt.%, 20-99 wt.%, 0.1-50 wt.%, and 0.1-20 wt.%, respectively, based on the total amount of the ink.
Next Patent: INK COMPOSITION