| 摘要 |
PCT No. PCT/EP93/03006 Sec. 371 Date Jun. 1, 1995 Sec. 102(e) Date Jun. 1, 1995 PCT Filed Oct. 26, 1993 PCT Pub. No. WO94/10087 PCT Pub. Date May 11, 1994Amorphous silicas suitable for use as abrasives in transparent toothpastes can be prepared by a precipitation route. These silicas are distinguished by having a BET surface area of 10 to 90 M2/g, a weight mean particle size of 5 to 15 micron, and a plastics abrasion value of 16 to 20, a transmission of at least 70% in the RI range from 1,430 to 1,443 and an oil absorbtion in the range from about 70 to about 150 cm3/100 g. |
