Forehearth colorant
AssigneeCorning Incorporated
InventorsPaul S. Danielson, Sheryl L. Hultman
Life of this patent
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Abstract
A non-melted, non-powder concentrated colorant material consists essentially of a flux that is not over 30% by weight of an alkali metal borate, a binder that is an alkali metal silicate and 35-60% V.sub.2 O.sub.5. The flux, binder and colorant oxide constitute at least 90% of the composition. A method of producing a black glass-ceramic material comprises forming the colorant material into particles and adding the particles to a precursor glass for the glass-ceramic while the glass is passing through the forehearth of a glass tank in a molten state.
Claims14
A non-melted, forehearth color concentrate in particle form consisting essentially of a flux, a binder and a colorant oxide, the flux being an alkali metal borate present in an amount sufficient to enable the concentrate to melt at 1300.degree. C., but not over 30% by weight the binder being an alkali metal silicate, and the colorant oxide being 35-60% by weight V.sub.2 O.sub.5, the flux, binder and colorant oxide constituting at least 90% of the forehearth color concentrate.
In a method of producing a black glass-ceramic material, the improvement comprising the steps of mixing powdered materials consisting essentially of up to 30% by weight of an alkali metal borate, 35-60% V.sub.2 O.sub.5, and an alkali metal silicate binder, forming the mixture into non-melted, non-powder, colorant particles, and adding the particles to a precursor glass for the glass-ceramic while that glass is passing through the forehearth of a glass tank in a molten state.
Dependencies are inferred from the claim text.