| 摘要 |
A process for the preparation of an aqueous alkali metal polysilicate solution having an SiO2 : alkali metal oxide mole ratio of 2.5 - 5.5 : 1 and a silica content of 16 - 23% by weight which comprises contacting a tetraalkoxysilane of the formula Si(OR)4 wherein each R is independently a straight or branched-chain alkyl group of 1 to 3 carbon atoms with an aqueous alkali metal hydroxide solution at a temperature between room temperature and the boiling point of the reaction mixture and at a temperature up to 100 DEG C. distilling over alcohol formed by the reaction of the silane with the alkali metal hydroxide. |
