| 摘要 |
PROBLEM TO BE SOLVED: To obtain a sparingly soluble builder based on an alkali silicate which exhibits high water-softening properties and is highly effective as a builder itself. SOLUTION: This sparingly soluble alkali silicate comprises a stratified alkali metal silicate finely dispersed in a non-stratified alkali metal silicate surrounding substance represented by the formula: xM12O.ySiO2. In the formula, M1 is an alkali metal and y/x is (1.9-500)/1. The crystalline alkali metal silicate as a whole preferably corresponds to the formula: aM12O.bMllO.cX2O3.dZ2 O5.eSiO2.fH2O, wherein M1 is an alkali metal; Mll is an alkaline earth metal; X is a main group III element of the periodic table; Z is a main group V element of the periodic table; and (a), (b), (c), (d), (e) and (f) satisfy the relationships 0<=a<=1, 0<=b<=0.5, 0<=c/e<=0.05, 0<=d/e<=0.25, 1.9<=e<=4, 0<=f<=20.
|
