Process for preparing refractory molded articles and binders therefor

A process for preparing a refractory molded article consisting of a mold with a core comprising the steps of:

• (a) forming a core matrix from an aggregate and a first binder;
• (b) impregnating said mold matrix formed in a aforementioned step (a) with the second binder consisting of an alcoholic solution containing one kind or two or more kinds of alkoxides selected from alkoxides of elements of Group 4A or Group 4B, excepting carbon, and Group 3A or Group 3B of the periodic table and their partial hydrolysates and an alkaline compound of alkali metal or alkaline earth metal and hydrolyzing;
• (c) positioning said core matrix inside a mold and injecting a lost model material into said mold to form a lost model enveloping said core matrix;
• (d) coating said lost model with a slurry and stucco particles alternately a plurality of times to form a refractory layer and drying;
• (e) allowing said lost model to vanish;
• and
• (f) firing simultaneously the aforementioned core matrix and refractory layer.