Patent ID: 7662363
Filing Date: 2010-02-16
Classification: A61K,A61Q,C01B,C01P

Abstract:
1. An amorphous silica suitable for use in a dental composition having a weight mean particle size in the range 3 to 15 μm with at least 90 per cent by weight of particles having a size below 20 μm, a Radioactive Dentine Abrasion (RDA) determined on an aqueous slurry of the silica powder of 100 to 220, a Pellicle Cleaning Ratio (PCR), when incorporated in a dental composition at 10 per cent by weight, greater than 85, the ratio of PCR to RDA being in the range 0.4:1 to less than 1:1 and having a Plastics Abrasion Value in the range 11 to 19.