URETHANE FOUNDRY BINDERS

摘要

A two-component foundry binder system which has use in the manufacture of foundry moulds and cores comprises, as a first component, a solution in a solvent of a phenolic resin having free hydroxyl group and, as a second component, a liquid polyisocyanate or a solution of a polyisocyanate which is capable of reacting with the phenolic resin of the first component, when the first and second components are mixed together, to produce a polyurethane. The solvent in the first component comprises at least one 1-4C alkenoic acid ester of a glycol or of a glycol ether.