Abstract: Binders for manufacture of precision casting molds are provided, which are highly stable and are advantageous in that these may impart a high strength to the green molds as obtained by forming an accumulative refractory coat layer on a water-soluble pattern and then taking off the pattern from the coat layer, that no interlayer cleavage occurs in the accumulative coat layer when the pattern is taken off in the formation of the green mold, that the binders may impart a high strength to fired molds, that the castings as obtained by the use of the present fired molds are free from the surface roughness and other surface faults and that the dimension accuracy of the castings is not deteriorated at all by the use of the present binders.The binders of the present invention are characterized by containing the following components (a), (b) and (c) and optionally (d):(a) an organo-silicasol capable of providing 5-50 parts by weight of SiO.sub.

Abstract: A binder for manufacture of a precision casting mold comprising a transparent solution containing an alkyl orthosilicate or an alkyl polysilicate having a polymerization degree of 2 to 10, and an amino-alkoxide of a metal selected from a group consisting of titanium, zirconium, tin and aluminum or a mixture thereof in the mol ratio (Si/N) of 0.01 to 1.0 calculated in terms of the silicon atom contained in the silicate and the basic nitrogen atom contained in the amino-alkoxide. This binder is excellent in preservation stability and workability and does not dissolve the surface of a water-soluble pattern.