| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of producing an inexpensive, safely treatable self-curing mold with a water-soluble alkali resol type phenol or the alkali salt of silicic acid as a binder which has satisfactory collapsibility of sand, and to provide a mold composition. SOLUTION: In the self-curing mold, a carbonate is used as a curing agent, and a carbon dioxide curing method is changed into a self-curing mold method. The self-curing mold consists of a refractory substance, a binder (a water-soluble alkali resol type phenolic resin or the alkali salt of silicic acid), and a curing agent (carbonate) therefor. The curing rate can be accelerated by adding acid crystal powder containing no free moisture to carbonate powder, mixing them, and using the mixture as a curing agent. On use of the carbonate in a liquid state, the settling rate can remarkably be delayed by increasing the viscosity of the dispersion liquid. COPYRIGHT: (C)2003,JPO
|
