| 摘要 |
<p>1297701 Coated abrasive articles NORTON CO 23 Feb 1970 [7 April 1969] 8470/70 Heading C4V Coated abrasive articles comprise a backing member having bonded thereto abrasive grains composed of alumino-zirconia containing 10 to 60% zirconia, which is in the form of eutectic colonies having numerical average size of 65 microns or less and, except in the eutectic region of 44-46% zirconia, primary crystals of alumina or zirconia of numerical average crystal size of 50 microns or less. The alumina-zirconia grains may be elongate and may be applied perpendicular to the plane of the backing over a first coating of abrasive grains. The backing may be a vulcanized fibre mat and the adhesive a phenolic resin.</p> |
