US 6,723,820 B1 · Solvent soluble poly(urethane/urea) resins

Abstract

Solvent based poly(urethane/urea) resins suitable for formulating flexographic and gravure laminating printing ink and coating compositions formed from a poly(urethane) prepolymer solution made from a blend of polymeric diols and diols reacted with diisocyanates and then with diamine in an organic solvent. The resin is prepared by adding the poly(urethane) prepolymer solution at a controlled rate to the diamine in a organic solvent which allows a resin solution to be formed, which may be used in the formulation of laminating printing ink and coating compositions without the need for adjuvants, grinding in polyvinyl butyral or blending with nitrocellulose base.

Claims49

Dependent claims

A solvent-soluble poly(urethane/urea) resin derived from a polyurethane prepolymer being the reaction product of:

(a) a diisocyanate component and a diol component having:
(i) a first diol having a molecular weight below 2000 and
(ii) a polymeric diol having a molecular weight below 3000;
wherein the —NCO/—OH ratio is less than 2 and containing 1.3 to 6.0 wt. % of unreacted —NCO groups and
(b) diamine;
wherein the amount of diamine is 100% to 120% based on the equivalents of unreacted —NCO groups and the polyurethane prepolymer is added to the diamine, in the absence of monoamine chain terminators, at a controlled rate of between about 3.33 to about 10 weight percent per minute of polyurethane prepolymer.

3 more elements

Dependencies are inferred from the claim text.

Solvent soluble poly(urethane/urea) resins

Life of this patent

Solvent soluble poly(urethane/urea) resins

Life of this patent

Abstract

Claims49