摘要 |
An abrasive having a high fluoride compatibility for toothpaste contains a precipitated, amorphous silica. The silica contains 10 to 300 parts of alkaline earth metal ions per million parts of amorphous silica. It has a) a radioactive dentine abrasion value of at least 40, b) a packing density of 0.24 to 0.55 g/ml, c) an oil absorption of 70 to 95 ml/100 g, d) a BET surface area of 100 to 250 m<2>/g, e) a percentage loss on ignition of 4 to 6% and f) fluoride compatibility values of at least 90% when it is incorporated into fluoride-containing toothpastes. |