| 摘要 |
<PICT:1011935/C1/1> In a process for the production of a ribbon of glass by flowing molten glass on to a liquid support (e.g. molten tin, silver, lead or their alloys), a liquid, particularly one based on boric anhydride, which wets glass, has a surface tension different to that of the glass, and does not react with or mix with the liquid support, is brought into contact with the edge of the glass ribbon, thus forming a band, the surface tension characteristics of which are different from those of the glass itself. Other oxides, such as those of potassium, lead or vanadium may be used in combination with the boric anhydride. A ribbon of glass 6 is formed on a molten bath of denser liquid 4, e.g. molten tin, and at the point 7 where the glass begins to spread out there is introduced into contact with each of its edges liquid boric anhydride through tubes 8. The boric anhydride also covers a small portion of the tin bath in the immediate neighbourhood of the glass ribbon to prevent oxidation. Alternatively, the liquid anhydride may form a film covering all the free surface of the liquid support not covered by the glass. |
