Method for producing glass for display substrate

Abstract

A glass for a display substrate composed of 50 to 70% SiO 2 , 10 to 25% Al 2 O 3 , 8.4 to 20% B 2 O 3 , 0 to 10% MgO, 6 to 15% CaO, 0 to 10% BaO, 0 to 10% SrO, 0 to 10% ZnO, 0 to 5% TiO 2 , 0 to 5% P 2 O 5 , 0.01 to 0.2% alkali metal, and from 0.01% to less than 0.4% ZrO 2 , as expressed in % by mass. The glass can have a β-OH value of 0.20/mm or more and an area of 0.1 m 2 or more. The glass is produced by mixing raw materials to provide the SiO 2 , Al 2 O 3 , B 2 O 3 , MgO, CaO, BaO, SrO, ZnO, TiO 2 , P 2 O 5 and alkali metal contents, electrically melting the raw materials in a melting furnace constructed of a high zirconia refractory; and refining, homogenizing and forming the glass melt.

1 . A glass for a display substrate comprising 50 to 70% of SiO 2 , 10 to 25% of Al 2 O 3 , 8.4 to 20% of B 2 O 3 , 0 to 10% of MgO, 6 to 15% of CaO, 0 to 10% of BaO, 0 to 10% of SrO, 0 to 10% of ZnO, 0 to 5% of TiO 2 , 0 to 5% of P 2 O 5 , 0.01 to 0.2% of an alkali metal, and from 0.01% to less than 0.4% of ZrO 2 , as expressed in % by mass. 
     
     
         2 . The glass for a display substrate according to  claim 1 , wherein the ZrO 2  content as expressed in % by mass is 0.01 to 0.3%. 
     
     
         3 . The glass for a display substrate according to  claim 1 , wherein the glass contains, as an alkali component, 0.007 to 0.2% of Na 2 O, 0 to 0.05% of Li 2 O and 0 to 0.05% of K 2 O as expressed in % by mass. 
     
     
         4 . The glass for a display substrate according to  claim 1 , wherein a β-OH value of the glass is 0.20/mm or more. 
     
     
         5 . The glass for a display substrate according to  claim 1 , which is 0.1 m 2  or more in area. 
     
     
         6 . The glass for a display substrate according to  claim 1 , which is used as a liquid crystal display substrate or an EL display substrate. 
     
     
         7 . A method for using a glass for a display substrate, which comprises using the glass for a display substrate as defined in  claim 1  as a substrate for a liquid crystal display or an EL display. 
     
     
         8 . A method for using a glass for a display substrate, which comprises using the glass for a display substrate as defined in  claim 2  as a substrate for a liquid crystal display or an EL display. 
     
     
         9 . A method for using a glass for a display substrate, which comprises using the glass for a display substrate as defined in  claim 3  as a substrate for a liquid crystal display or an EL display. 
     
     
         10 . A method for using a glass for a display substrate, which comprises using the glass for a display substrate as defined in  claim 4  as a substrate for a liquid crystal display or an EL display. 
     
     
         11 . A method for using a glass for a display substrate, which comprises using the glass for a display substrate as defined in  claim 5  as a substrate for a liquid crystal display or an EL display. 
     
     
         12 . A method for using a glass for a display substrate, which comprises using the glass for a display substrate as defined in claim  6  as a substrate for a liquid crystal display or an EL display. 
     
     
         13 . A method for producing a glass for a display substrate comprising the steps of:
 preparing glass raw materials mixed so that the glass comprises 50 to 70% of SiO 2 , 10 to 25% of Al 2 O 3 , 8.4 to 20% of B 2 O 3 , 0 to 10% of MgO, 6 to 15% of CaO, 0 to 10% of BaO, 0 to 10% of SrO, 0 to 10% of ZnO, 0 to 5% of TiO 2 , 0 to 5% of P 2 O 5 ;   electrically melting the glass raw materials in a melting furnace constructed of a high zirconia refractory; and   refining, homogenizing and forming the glass melt;   wherein the glass raw materials are mixed so that an alkali content of the resultant glass is 0.01 to 0.2% as expressed in % by mass.   
     
     
         14 . The method for producing a glass for a display substrate according to  claim 13 , wherein the glass raw materials are mixed so that an alkali component is 0.007 to 0.2% of Na 2 O, 0 to 0.05% of Li 2 O, and 0 to 0.05% of K 2 O as expressed in % by mass. 
     
     
         15 . The method for producing a glass for a display substrate according to  claim 13 , wherein a β-OH value of the resultant glass is 0.20/mm or more. 
     
     
         16 . The method for producing a glass for a display substrate according to  claim 13 , wherein a ZrO 2  content of the resultant glass is from 0.01% to less than 0.4% as expressed in % by mass. 
     
     
         17 . The method for producing a glass for a display substrate according to  claim 13 , wherein the ZrO 2  content of the resultant glass is 0.01 to 0.3% as expressed in % by mass. 
     
     
         18 . A glass for a display substrate, which is produced by a method as defined in  claim 13 . 
     
     
         19 . A glass for a display substrate, which is produced by a method as defined in  claim 14 . 
     
     
         20 . A glass for a display substrate, which is produced by a method as defined in  claim 15 . 
     
     
         21 . A glass for a display substrate, which is produced by a method as defined in  claim 16 . 
     
     
         22 . A glass for a display substrate, which is produced by a method as defined in  claim 17 .