Method for decreasing bubble lifetime on a glass melt surface

Patent metadata

Field	Value
Publication number	US-11505487-B2
Application number	US-201816494020-A
Country	US
Kind code	B2
Filing date	Mar 16, 2018
Priority date	Mar 16, 2017
Publication date	Nov 22, 2022
Grant date	Nov 22, 2022

Abstract

A method of reducing bubble lifetime on the free surface of a volume of molten glass contained within or flowing through a vessel including a free volume above the free surface, thereby, minimizing re-entrainment of the bubbles back into the volume of molten glass and reducing the occurrence of blisters in finished glass products.

First claim

What is claimed is:

1. A method of reducing bubble lifetime in molten glass, comprising:
forming molten glass in an electrically-boosted melting vessel;
directing the molten glass through a vessel downstream of the melting vessel, the downstream vessel containing a free volume above a free surface of the molten glass in the downstream vessel; and
flowing a humidified gas into the free volume, wherein the humidified gas comprises ≥10% O 2 by volume and a dew point in a range from 41° C. to 92° C.

2. The method according to claim 1 , wherein the humidified gas comprises ≤90% O 2 by volume.

3. The method according to claim 1 , wherein a temperature of the molten glass in the downstream vessel is equal to or greater than about 1300° C.

4. The method according to claim 1 , further comprising heating the humidified gas prior to flowing the humidified gas into the downstream vessel.

5. The method according to claim 1 , further comprising heating the humidified gas to a temperature greater than the dew point prior to flowing the humidified gas into the downstream vessel.

6. A method of reducing bubble lifetime in molten glass, comprising:
forming molten glass in an electrically-boosted melting vessel;
flowing the molten glass through a vessel downstream of the melting vessel, the downstream vessel containing a free volume between a free surface of the molten glass and a top of the downstream vessel, the molten glass comprising a bubble layer no greater than a single bubble deep on the free surface;
flowing a humidified gas comprising oxygen into the free volume, wherein the humidified gas comprises ≥10% O 2 by volume and a dew point in a range from about 41° C. to about 92° C.

7. The method according to claim 6 , wherein a wall of the downstream vessel comprises platinum.

8. The method according to claim 6 , wherein a temperature of the molten glass in the downstream vessel is equal to or greater than about 1300° C.

9. The method according to claim 6 , further comprising directing the molten glass to a forming body and drawing the molten glass from the forming body as a ribbon.

10. A method of reducing bubble lifetime in molten glass, comprising:
forming molten glass in an electrically-boosted melting vessel;
directing the molten glass through a vessel downstream of the melting vessel, the molten glass comprising a plurality of bubbles on a free surface of the molten glass;
reducing a surface tension gradient on membranes of the plurality of bubbles with a surfactant introduced into a free volume of the downstream vessel over the free surface, wherein the surfactant comprises a humidified gas comprising 10% 02 by volume and a dew point in a range from about 41° C. to about 92° C.

11. The method according to claim 10 , wherein a temperature of the molten glass in the downstream vessel is equal to or greater than about 1300° C.

12. The method according to claim 10 , further comprising directing the molten glass to a forming body and drawing the molten glass from the forming body as a ribbon.

Assignees

• Corning Inc

Inventors

• Adkins Laura Rose Vancott
• Choi Soon-Yong
• Delamielleure Megan Aurora
• Dorfeld William Gurney
• Laronze Pierre
• Ryu Sang-Ryoun

Classifications

• C03B5/225 Primary

  Refining (C03B5/18 takes precedence {; Refining agents C03C1/004}) · CPC title

• C03B7/07

  Electric means · CPC title

• C03B17/064

  by the overflow downdraw fusion process; Isopipes therefor · CPC title

• C03B5/16 Primary

  Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces · CPC title

• C03B5/163 Primary

  Electrochemical treatments, e.g. to prevent bubbling or to create bubbles (C03B5/1672, C03B5/185 take precedence) · CPC title