CEMENTING COMPOSITION

PURPOSE:To obtain a cementing composition which is temporally well balanced between usable time and various physical properties-occurring time at the time of application operation and in which efflorescence phenomenon is inhibited by blending zinc borate as a hardener with a water glass-type hydraulic cement composition consisting of water-soluble silicic acid alkali and inorganic hardener. CONSTITUTION:Zinc borate is blended with the above water glass-type hydraulic cement composition as the hardener by 1-40 pts.wt. for 100 pts.wt. of water-soluble silicic acid alkali on the basis of solids dried at 110 deg.C, by which the cementing composition in which temporal balance between usable time and various physical properties-occurring time can be regulated can be obtained. As the above water-soluble alkali, a powdered or liquid substance called water glass is usually used. Further, As the above inorganic hardener, e.g., oxide, such as ZnO, is used. Moreover, it is preferable to use, as the above zinc borate, the one in which m=0.5-2.5 is satisfied when its compositional formula is represented by ZnO.mB2O3.nH2O on the basis of oxide in order to effectively produce the effects of the above functions.