Title:
A glass substrate and a manufacturing method for the same
Document Type and Number:
Japanese Patent JP5987836
Kind Code:
B2
Abstract:
The present invention provides a glass substrate having a high glass transition temperature, in which a compaction (C) is small in heat treatment at low temperature (150 to 300°C). A glass substrate containing, in terms of mol% on the basis of the following oxides: from 60 to 79% of SiO 2 ; from 2.5 to 18% of Al 2 O 3 ; from 0 to 3% of B 2 O 3 ; from 1 to 15% of MgO; from 0 to 1% of CaO; from 0 to 1% of SrO; from 0 to 1% of BaO; from 0 to 1% of ZrO 2 ; from 7 to 15.5% of Na 2 O; from 0 to 3% of K 2 O; and from 0 to 2% of Li 2 O; wherein Na 2 O+K 2 O is from 7 to 15.5%, Na 2 O/(Na 2 O+K 2 O) is from 0.77 to 1, MgO+CaO+SrO+BaO is from 1 to 18%, MgO-0.5Al 2 O 3 is from 0 to 10, and MgO+0.5Al 2 O 3 is from 1 to 20, wherein the glass substrate has: a glass transition temperature of from 580 to 720°C; an average coefficient of thermal expansion within a range of from 50 to 350°C of from 65×10 -7 to 85×10 -7 /°C; a compaction (C) of 15 ppm or less; a glass surface devitrification temperature (T c ) of from 900 to 1,300°C; a glass internal devitrification temperature (T d ) of from 900 to 1,300°C; a temperature (T 4 ) at which a viscosity reaches 10 4 dPa·s of from 1,100 to 1,350°C; a relationship (T 4 -T c ) between the temperature (T 4 ) at which a viscosity reaches 10 4 dPa·s and the glass surface devitrification temperature (T c ) of from -50 to 350°C; and a relationship (T 4 -T d ) between the temperature (T 4 ) at which a viscosity reaches 10 4 dPa·s and the glass internal devitrification temperature (T d ) of from -50 to 350°C.
Inventors:
Manabu Nishizawa
Application Number:
JP2013541696A
Publication Date:
September 07, 2016
Filing Date:
October 17, 2012
Export Citation:
Assignee:
Asahi Glass Co., Ltd.
International Classes:
C03C3/085; C03C3/087; C03C3/091; C03C3/093
Domestic Patent References:
| JP2010059038A | ||||
| JP2010527892A | ||||
| JP8133778A | ||||
| JP11240735A |
Foreign References:
| WO2011049100A1 | ||||
| WO2011152414A1 |
Attorney, Agent or Firm:
Hidekazu Miyoshi
Shunichi Takahashi
Masakazu Ito
Toshio Takamatsu
Shunichi Takahashi
Masakazu Ito
Toshio Takamatsu