C - Chemistry – Metallurgy – 01 – B
Patent
C - Chemistry, Metallurgy
01
B
6/176, 23/192, 6
C01B 33/193 (2006.01) C09C 1/30 (2006.01) C09C 3/10 (2006.01) C09C 3/12 (2006.01) C09D 7/00 (2006.01) C09D 7/12 (2006.01)
Patent
CA 1340129
A finely divided precipitated silica having a structure with a BET surface area (DIN 60132) of between 150 and 350 sq.m/g, tamped density (DIN 53194) of between 60 and 120 g/litre, DBP number of between 3.0 and 4.0 ml/g and particle size distribution of at least 70% of 1 to 6 µm. It can be produced by heating a mixture of water and sodium silicate to a temperature of 70 to 80°C while stirring by metered addition of concentrated sulphuric acid until one half of the alkali present is neutralized, by treating the reaction mixture with a shear unit while simultaneously increasing the temperature to 86~5°C, when required, by adding concentrated sulphuric acid at a higher rate during a period of 30 to 120 minutes until the pH value of the nascent silica suspension is 3.0 to 3.5, by diluting the silica suspension, when required, by separating the coarse fraction by means of a centrifugal pump or of a hydrocyclone, by filtering off the silica by means of conventional filtering devices, by washing the silica filter cake until it is free from sulphate, by redispersing the silica filter cake by adding water by means of an agitator unit so as to obtain a suspension having a content of solids of 80~10 g per litre, adding, when required, alkyl dimethyl benzyl-ammonium chloride to this suspension and spray-drying the suspension thus obtained and, when required, grinding the dried product. The precipitated silica, either uncoated or coated, can be used as a dulling agent in varnishes.
598876
Bauer Dieter
Kerner Dieter
Schmidt Felix
Wagner Adolf
Aktiengesellschaft Degussa
Bauer Dieter
Kerner Dieter
Marks & Clerk
Schmidt Felix
LandOfFree
Finely divided divided precipitated silica having a high... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Finely divided divided precipitated silica having a high..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Finely divided divided precipitated silica having a high... will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-1273648