A method for preparing a novolak phenol-formaldehyde resin, a method for making resin coated granules for foundry moulding and a foundry mould component made from the granules.

摘要

Resins for use in making resin-coated granules are made by preparing a novolak resin from a phenol and formaldehyde in the presence of lactose and<Sub>/</Sub>or galactose, using an acid catalyst. Melt-coating the resin with an amine curing agent on to particulate refractory material gives resin-coated granules which can be moulded to make foundry moulds.

The lactose and or galactose can replace part of the phenol conventionally employed in preparing novolak resins and avoid the need for plasticisers.