| 摘要 |
1282866 Treating glass surfaces PILKING- TON BROS Ltd D G LOUKES and A EDWARDS 6 Aug 1969 [16 Aug 1968] 39367/68 Heading C1M To produce glass having desired surface characteristics, particularly for colouring the glass or to give an electrically conductive surface film, the glass at, or heated to, a temperature at which it is susceptible to surface modification has directed thereon a metal compound in vapour form under oxidizing conditions which are regulated to promote oxidation of the metal compound at the glass surface only, and to produce the metal oxide as it is dissolved into a surface layer of the glass without just existing in isolated phase. Rolled or pressed glass can be so treated but the apparatus disclosed relates to float glass only. Silica glass may be treated and shapes referred to are flat, curved or profiled sheets, TV face panels and building blocks. Metals suggested are Na, K, Sb, Bi, Pb, Sn, Cu, Co, Mn, Cr, Fe, Ni, Si or Ti or alloys thereof, Co-Cr and Na-Bi being mentioned. A reactive gas, particularly chlorine (with nitrogen) or oxygen for tin (giving stannous oxide vapour) is passed over the metal either in solid or molten form and oxygen (with nitrogen) either added to the reactive gas or directed separately at the glass surface. Subsequently, the oxide in the surface may be reduced by passing through a nitrogen atmosphere with e.g. 1% hydrogen added. As shown in Fig. 4, float glass 30 on molten tin 10 passes under a bar stretching across the full width of the bath of tin. The bar may be wholly of the metal or part 44 of metal and part 45 of a refractory material. A reactive gas passes through the space between the bar 44 and the surface 38 of the glass from a tube 34 and the oxidizing gas is introduced through the bar 45 at 46. A tube 40 is connected to vacuum to exhaust the gases. As in Fig. 5, reactive gas from tube 54 is passed over a boat 51 with molten metal 52 under an enclosure 52 with leading wall 55 adjacent to the glass surface. Oxygen and nitrogen is introduced from a slot 57 in tube 56 and exhaust gases removed by tube 61. As in Fig. 6, the enclosure 60a is tubular and forms also exhaust tubes 61a, 62, the metal compound in vapour form being introduced by a central tube 66 with slot 67 and oxygen and nitrogen fin tubes 73, 74 with slots 75, 76 angled towards the central tube. |
