FOUNDRY AGGREGATE BINDERS

摘要

1405116 Foundry compositions HOOKER CHEMICALS & PLASTIC CORP 28 Sept 1972 [26 Oct 1971 10 Nov 1971] 45473/74 Divided out of 1405114 Headings C3N and C3R Foundry compositions for preparing shaped foundry articles comprise a foundry aggregate, e.g. sand and as a curable binder a mixture of a polyisocyanate and a phenolic compound of the formula wherein X represents an oxygen or sulphur atom, y represents an alkylidene, alkylidene substituted by one or more cycloalkyl or haloalkyl groups, aryl bis alkylene or arylene group, -S-, -S-S- or -SO 2 -, n is 0 or 1, R 5 and R 6 each represent a hydrogen or halogen atom, alkyl, haloalkenyl or alkenyl group of up to 6 carbon atoms, alkaryl or arylalkyl group, a is 0 or an integer from 1 to 4, b is atleast 1, and the sum of a and b is at most 5, or an ester of such a phenolic compound with an aromatic carboxylic acid. Most preferably the polyisocyanate is a polyaryl polyisocyanate, e.g. polyphenyl polymethylene polyisocyanate and the phenolic compound is Bisphenol A. The composition may be cured by passing a tertiary amine therethrough.