| 摘要 |
PROBLEM TO BE SOLVED: To obtain an accelerating agent free from reduction in quicksetting properties in a long-term preservation, by including calcium aluminate, a sodium aluminate of a specific composition and a sulfate. SOLUTION: This accelerating agent comprises an amorphous calcium aluminate which has preferably >=5,000 cm<2> /g particle size as Blaine value and is obtained by quenching a heat-treated material preferably corresponding to a composition of the formula (CaO)12 (Al2 O3 )7 , a sodium aluminate which has preferably <=0.3 mm, more preferably 0.05-0.2 mm maximum particle diameter and the molar ratio of Na2 O/A12 O3 of 100-1.30, preferably 1.05-1.20 and a sulfate which is preferably gypsum, more preferably anhydrous gypsum. The particle size of the gypsum is >=2,500 cm<2> /g, preferably >=5,000 cm<2> /g Blaine value. A spraying material is obtained by including a cement and the accelerating agent. |
