| 摘要 |
<p>PURPOSE:To obtain an ink composition remarkably excellent in stability for a long period of time by mixing, as a binder, a polyurethane resin containing p-aminobenzoic acid added at a stage of synthesizing its prepolymer. CONSTITUTION:(A) An excessive amount of a diisocyanate such as isophorone diisocyanate is made to react with (B) a polyol such as 3-methylpentanediol adipate and (C) p-aminobenzoic acid to synthesize a prepolymer. The resultant prepolymer is further reacted with (D) a diamine such as isophorone diamine to obtain a straight-chain polymer, and then the terminal isocyanate is reacted with monoisopropanol amine, etc., to synthesize a stable polyurethane resin. The synthesized resin is blended in an amount of about 3-20wt.%, thus obtaining the objective composition.</p> |
