| 摘要 |
<p>In a glass polishing process the surface of the glass is rubbed with a liquid suspension of an abrasive composition, which comprises (a) at least one finely divided oxide selected from zirconium dioxide, ceric oxide, ferric oxide, alumina, titanium dioxide, stannic oxide or silica, and (b) at least one finely divided oxide selected from zinc oxide, cadmium oxide or lead oxide. In general, the particle size of the constituents should be less than 3m and preferably less than 2m , and ingredient (b) comprises 5-95% by weight of the total composition. The compositions may be prepared by calcining together two or more of the components and then pulverizing the product to the required degree of fineness. Silica may be present as an impurity, and the suspension to be used may contain deflocculants and thickeners. If desired, the additive (b) may be present in a combined form, either with one of the polishing agents (a) or with another additive (b); zinc titanate (Zn2TiO4) is the preferred additive of this type, but in all cases a polishing agent (a) in uncombined form must be present.</p> |
