Title:
METHOD FOR PRODUCING ALKALI-FREE GLASS SUBSTRATE, AND ALKALI-FREE GLASS SUBSTRATE
Document Type and Number:
WIPO Patent Application WO/2019/049768
Kind Code:
A1
Abstract:
Provided are: an alkali-free glass substrate which has high strain point, while having excellent bubble quality; and a method for producing this alkali-free glass substrate. A method for producing an alkali-free glass substrate according to the present invention is characterized by comprising: a batch preparation step wherein a starting material batch is prepared to be an alkali-free glass that has a glass composition containing, in mass%, 50-80% of SiO2, 15-30% of Al2O3, 0-4.5% of B2O3, 0-10% of MgO, 0-15% of CaO, 0-10% of SrO, 0-15% of BaO, 0-5% of ZnO, 0-5% of ZrO2, 0-5% of TiO2, 0-15% of P2O5 and 0-0.5% of SnO2; a melting step wherein the thus-prepared starting material batch is melted; a refining step wherein the molten glass is refined; and a molding step wherein the refined glass is molded into a plate. This method for producing an alkali-free glass substrate is also characterized in that the starting material batch is melted so that the bubble diameter enlargement initiation temperature of the thus-obtained glass is lower than the highest temperature during the refining step.
Inventors:
HAYASHI MASAHIRO (JP)
HASEGAWA TORU (JP)
SAKURABAYASHI TORU (JP)
HASEGAWA TORU (JP)
SAKURABAYASHI TORU (JP)
Application Number:
PCT/JP2018/032147
Publication Date:
March 14, 2019
Filing Date:
August 30, 2018
Export Citation:
Assignee:
NIPPON ELECTRIC GLASS CO (JP)
International Classes:
C03B5/225; C03C3/083; C03C3/085; C03C3/087; C03C3/091; C03C3/093; C03C3/097; G09F9/30
Domestic Patent References:
| WO2016185976A1 | 2016-11-24 | |||
| WO2009054314A1 | 2009-04-30 | |||
| WO2014157349A1 | 2014-10-02 |
Foreign References:
| JP2013151407A | 2013-08-08 |
Attorney, Agent or Firm:
SHIN-EI PATENT FIRM, P.C. (JP)
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