FINING AGENTS FOR SILICATE GLASSES
First Claim
1. A silicate glass, the silicate glass having a seed concentration of less than about 1 seed/cm3, wherein the silicate glass is formed from a batch or raw materials that includes at least one fining agent, wherein the fining agent comprises at least one inorganic compound that acts as of a source of water at a temperature where a melt is formed, and wherein the silicate glass and the at least one fining agent are substantially free of antimony and arsenic.
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Accused Products
Abstract
A fining agent for reducing the concentration of seeds or bubbles in a silicate glass. The fining agent includes at least one inorganic compound, such as a hydrate or a hydroxide that acts as a source of water. In one embodiment, the fining agent further includes at least one multivalent metal oxide and, optionally, an oxidizer. A fusion formable and ion exchangeable silicate glass having a seed concentration of less than about 1 seed/cm3 is also provided. Methods of reducing the seed concentration of a silicate glass, and a method of making a silicate glass having a seed concentration of less than about 1 seed/cm3 are also described.
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Citations
24 Claims
- 1. A silicate glass, the silicate glass having a seed concentration of less than about 1 seed/cm3, wherein the silicate glass is formed from a batch or raw materials that includes at least one fining agent, wherein the fining agent comprises at least one inorganic compound that acts as of a source of water at a temperature where a melt is formed, and wherein the silicate glass and the at least one fining agent are substantially free of antimony and arsenic.
- 12. A fining agent for silicate glasses, the fining agent comprising an inorganic compound that acts as of a source of water at a temperature at which a melt is formed, wherein the water vaporizes and expands existing bubbles in the melt and allows the expanded bubbles to rise to the surface of the melt and escape the melt to reduce the seed concentration in the silicate glass to less than about 1 seed/cm3, and wherein the fining agent is substantially free of arsenic and antimony.
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19. A method of reducing a concentration of seeds in a silicate glass, the method comprising the steps of:
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a. providing a batch, the batch comprising raw materials for the silicate glass and at least one fining agent in an amount sufficient to generate one mole of water vapor per kilogram of glass, wherein the at least one fining agent is substantially free of arsenic and antimony and comprises at least one inorganic compound that acts as of a source of water at a temperature where a melt is formed; b. melting the batch to form a melt, the melt having a surface; c. vaporizing the water to form water vapor, wherein the water vapor expands existing bubbles in the melt; d. allowing the expanded bubbles to rise to the surface of the melt and escape the melt to reduce the concentration of the plurality of seeds in the silicate glass melt to less than about 1 seed/cm3; and e. removing at least a portion of the plurality of bubbles from the melt. - View Dependent Claims (21)
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22. A method of making a silicate glass having a seed concentration of less than about 1 seed/cm3, the method comprising the steps of:
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a. providing a batch, the batch comprising raw materials for the silicate glass and at least one fining agent in an amount sufficient to generate one mole of water vapor per kilogram of glass, wherein the at least one fining agent is substantially free of arsenic and antimony and comprises at least one inorganic compound that acts as of a source of water at a temperature where a melt is formed; b. melting the batch to form a silicate glass melt; c. vaporizing the water to form water vapor, wherein the water vapor expands existing bubbles in the melt; d. allowing the expanded bubbles to rise to the surface of the melt and escape the melt to reduce the seed concentration in the melt below a predetermined concentration; e. removing at least a portion of the coalesced bubbles and seeds from the melt; and f. solidifying the melt to form the silicate glass, wherein the glass has a seed concentration of less than about 1 seed/cm3. - View Dependent Claims (23, 24)
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Specification