| 摘要 |
A binder composition for producing articles of bonded particulate material such as foundry moulds or cores comprises an alkaline aqueous solution of a resol phenol-aldehyde resin, an oxyanion which can form a stable complex with the resin, and a propylene glycol alkyl ether, in which the amount of alkali present in the solution is sufficient to substantially prevent stable complex formation between the resin and the oxyanion and the amount of propylene glycol alkyl ether is such that the propylene glycol alkyl ether is miscible with the aqueous solution. Bonded articles are produced by passing carbon dioxide gas through articles formed from a mixture of particulate material and the binder composition so as to produce stable complex formation and curing of the resin.
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