| 摘要 |
<p>PURPOSE:To obtain the title binder improved in adhesion to a print, boiling resistance, etc., by using a polyurethane resin obtained by reacting a specified polyester-diol with a diisocyanate compound and a chain extender as the principal component. CONSTITUTION:A polyester-diol of a number-average MW of 500-4000 is obtained by reacting a dibasic acid component comprising at least 50wt.% 20-36C dibasic acid (e.g. dimer acid) and optionally other components with a glycol component. The obtained diol is reacted with a diisocyanate in an amount to give NCO groups in excess of the OH groups of the diol to obtain a prepolymer having an NCO group on each end. This prepolymer is reacted with a chain extender and optionally chain terminator in a solvent to obtain a polyurethane resin of a number-average MW of 5000-10000. This resin is mixed with optionally other resins to obtain the title binder. This binder is mixed with a colorant, a solvent and optionally a surfactant, a wax, and other additives to obtain a printing ink composition.</p> |
