Method for producing glass article

Patent metadata

Field	Value
Publication number	US-2021122658-A1
Application number	US-201816645045-A
Country	US
Kind code	A1
Filing date	Sep 11, 2018
Priority date	Sep 13, 2017
Publication date	Apr 29, 2021
Grant date	—

Abstract

A manufacturing method for a glass article includes a supply step of supplying a glass raw material onto a surface of a molten glass accommodated in a melting chamber of a glass melting furnace from a supply unit mounted to a front wall of the melting chamber, and a melting step of melting the supplied glass raw material through heating with an electrode immersed in the molten glass in the melting chamber. The method also includes an outflow step of causing the molten glass to flow outside the melting chamber from an outflow port provided at a rear wall of the melting chamber, wherein 60% to 95% of an area of the surface of the molten glass in the melting chamber is covered with the glass raw material supplied in the supply step.

First claim

1 . A manufacturing method for a glass article, comprising:
a supply step of supplying a glass raw material onto a surface of molten glass accommodated in a melting chamber of a glass melting furnace from a supply unit mounted to a front wall of the melting chamber; a melting step of melting the supplied glass raw material through heating with an electrode immersed in the molten glass in the melting chamber; and an outflow step of causing the molten glass to flow outside the melting chamber from an outflow port provided at a rear wall of the melting chamber, wherein 60% to 95% of an area of the surface of the molten glass in the melting chamber is covered with the glass raw material supplied in the supply step.

2 . The manufacturing method for a glass article according to claim 1 , wherein, when a length of the surface of the molten glass along a flowing direction of the glass raw material in the melting chamber is represented by L, and a distance between the glass raw material located on a most upstream side and the glass raw material located on a most downstream side in the flowing direction is represented by R, the following relationship is satisfied.
R≥0.65L

3 . The manufacturing method for a glass article according to claim 1 , wherein a difference in temperature between a temperature of a surface of the glass raw material supplied in the supply step and a temperature of the molten glass present on a bottom wall of the melting chamber is set to 200° C. or more.

4 . The manufacturing method for a glass article according to claim 1 , wherein a difference in viscosity between a viscosity of the molten glass present at an interface with the glass raw material supplied in the supply step and a viscosity of the molten glass present on a bottom wall of the melting chamber is set to 2,500 dPa·s or more.

5 . The manufacturing method for a glass article according to claim 1 ,
wherein the front wall has mounted thereto a plurality of supply units, and wherein a gap in which the molten glass is exposed is formed between the glass raw materials supplied from the plurality of supply units.

6 . The manufacturing method for a glass article according to claim 1 , wherein at least part of a portion of the surface of the molten glass in the melting chamber, the portion being prevented from being covered with the glass raw material, is covered with a bubble layer.

Assignees

• Nippon Electric Glass Co

Inventors

• Hasegawa Toru
• Sakurabayashi Toru

Classifications

• Y02P40/57

  Improving the yield, e-g- reduction of reject rates · CPC title

• C03B5/03

  Tank furnaces · CPC title

• C03B3/005 Primary

  using screw feeders · CPC title

• C03B5/027 Primary

  by passing an electric current between electrodes immersed in the glass bath, i.e. by direct resistance heating · CPC title

• C03B5/16 Primary

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