Title:
石英ガラスるつぼの製造方法および光学ガラス溶融用石英ガラスるつぼ
Document Type and Number:
Japanese Patent JP7379054
Kind Code:
B2
Abstract:
To provide a manufacturing method of low-devitrifiable opaque quartz glass crucible and to provide the quartz glass crucible made of natural silica powder containing a prescribed amount of an Al component and a Ca component as a raw material, the manufacturing method properly crystallizing the quartz glass to suppress crucible deformation and cracks.SOLUTION: A manufacturing method of a quartz glass crucible includes a step 1 for loading raw material silica powder having a molar concentration ratio (Al/Ca) of 15 or more calculated from an Al concentration and a Ca concentration measured by chemical purity analysis into a rotating mold, and a step 2 for inserting an ark electrode in the mold and ark-melting a raw material silica powder layer deposited on the inner surface of the mold to vitrify the powder layer. A quartz glass crucible for melting optical glass has an Al concentration of 55 wt.ppm or more and 100 wt.ppm or less, a Ca concentration of 1.2 wt.ppm or more and 9.5 wt.ppm or less, and a molar ratio (Al/Ca) of 15 or more.SELECTED DRAWING: None
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Inventors:
Mirai Kudo
Application Number:
JP2019181106A
Publication Date:
November 14, 2023
Filing Date:
October 01, 2019
Export Citation:
Assignee:
Momentive Technologies Yamagata Co., Ltd.
International Classes:
C30B15/10; C03B20/00; C30B29/06
Domestic Patent References:
| JP2010132534A | ||||
| JP2002326827A |
Attorney, Agent or Firm:
Satoshi Furuya
Akihiro Ohnishi
Rei Hosoi
Akihiro Ohnishi
Rei Hosoi