摘要:
A method for forming flat glass of high optical quality on a bath of molten tin, in which the glass has a relatively short residence time, is disclosed. The method involves adding an oxidizing agent to the hotter regions of the molten tin bath which is believed to modify the bottom or tin-contacting surface of the glass while the glass is on the bath of molten tin so as to be able to produce glass substantially free of top surface distortion, a problem which is particularly severe for glass having relatively short residence times on molten tin.
摘要:
The method of improving the cleaning of float forming chamber roofs is disclosed. The method involves the use of heated forming or nitrogen gas which is directed against the surface of the roof. In a preferred embodiment, hydrogen sulfide or other sulfur containing gas is added to the gas directed against the roof in order to aid in cleaning by converting elemental tin to tin sulfide which will sublimate at the temperature of the heated gas.
摘要:
Crystallized glass has hitherto been made by the use of the mineral petalite as the source of lithium values. Petalite is in short supply, and when attempts are made to use lithium carbonate or a similar lithium salt in place of petalite in the glass batch, unwanted microcracking develops during a subsequent crystallizing heat treatment with certain glass compositions. Such microcracking can be avoided by using a purposefully small addition to the petalite-free batch of an alkali metal salt, wherein the alkali metal is selected from the class consisting of potassium, rubidium and cesium.
摘要:
A method of reducing tin drip by introduction of a sulfur gas into the forming chamber is disclosed. The sulfur containing gas reacts with the elemental tin present in the chamber superstructure and forms compounds such as tin sulfide which will sublime upon heating and that are unlikely to drip from the ceiling.
摘要:
Glass-ceramic articles having compositional inhomogeneities are provided with uniformly colored gray stain decorations by heat treating a palladium-containing staining material prior to application onto glass-ceramic articles which have been crystallized by a separate heat treatment, and then subjecting the glass-ceramic articles in contact with the staining material to another heat treatment to produce the stain decorations.