| 摘要 |
1,150,764. Sodium aluminium silicate pigments. DEUTSCHE GOLDUND SILBERSCHEIDEAN-STALT. 4 July, 1966 [9 July, 1965], No. 29944/66. Heading C1A. Sodium aluminium silicate pigment is produced by precipitation from alkali metal silicate solutions and aluminium sulphate solutions wherein these solutions are simultaneously or successively combined with stirring and in the presence of water over a period ranging from 30 minutes to 10 hours, at an elevated temperature preferably between 50‹ and 100‹ C. and at a pH value between 10 and 12, the suspension being adjusted at an elevated temperature to a pH value of from 1À5 to 8 by the addition of aluminium sulphate and/or mineral acid on completion of the precipitation. A dilute waterglass solution containing 8 to 16% SiO 2 and having a molar ratio of Na 2 O: SiO 2 = 1: 3À2 to 1: 3À4, and dilute aluminium sulphate solution of density 1À015 to 1À08 may be used in the precipitation. |
