| 摘要 |
1,128,795. Satin white. FELDMUHLE A.G. 31 Dec., 1965 [31 Dec., 1964], No. 55447/65. Heading C1A. In the preparation of satin white (approx. 3CaO.Al 2 O 3 .3CaSO 4 .31H 2 O) by reacting CaO or Ca(OH) 2 with a stoichiometric amount of aqu. Al 2 (SO 4 ) 3 soln., the CaO or Ca(OH) 2 is first added to a portion, e.g. 30-90%, of the Al 2 - (SO 4 ) 3 and the remainder of the Al 2 (SO 4 ) 3 is then added. The CaO or Ca(OH) 2 is preferably added as a solid to an Al 2 (SO 4 ) 3 soln. of concn. 1-5‹ BÚ. The mixture may be stirred using a stirrer with a circumferential speed of more than 700 m/sec. After all the reactants have been added it may be allowed to attain a pH of 10À6-10À8 before separating off the aqueous paste of satin white. |
