| 摘要 |
<p>Case 4480 The present invention relates to foundry compositions containing propylene glycol monoacetate, a silica base and a silicate, The use of propylene glycol monoacetate as ester hardeners imparts greater compressive strength to foundry cores and the strength is built up more rapidly than with conventional ester hardeners. This is believed to be due at least in part to the total miscibility of this ester with water and to the purity of the ester product.</p> |
