Press molding method for glass and manufacturing method for glass substrate using this method

Abstract

The present invention relates to a glass substrate of which the outer periphery portion is unprocessed. The present invention also relates to a manufacturing method for a glass substrate of which the outer periphery portion is unprocessed, characterized in that a first lapping process, a second lapping process, a polishing process and a washing process are carried out after a press molding process is carried out so as to compress glass between an upper mold and a lower mold without regulating the edge surface of the outer periphery portion of the glass and, then, a crystallization process or an annealing process is carried out.

What is claimed is:  
     
         1 . A glass substrate of which the outer periphery portion is unprocessed.  
     
     
         2 . A glass substrate of which the outer periphery portion is unprocessed having the center of gravity as the center of rotation.  
     
     
         3 . The glass substrate of which the outer periphery portion is unprocessed according to  claim 1 , wherein the outer periphery edge surface is a free-form surface having a surface coarseness 2.5 nm, or less, and having a maximum surface coarseness of 150 nm, or less.  
     
     
         4 . The glass substrate of which the outer periphery portion is unprocessed according to  claim 1 , wherein E/ρ (E is the Young's modulus (GPa) and ρ is the specific gravity (g/cm 3 )) is 27 to 52.  
     
     
         5 . The glass substrate of which the outer periphery portion is unprocessed according to  claim 1 , wherein αs (αs is a linear thermal expansion coefficient in the range of 0° C. to 100° C.) is 40×10 −7 /° C. to 130×10 −7 /° C.  
     
     
         6 . A glass substrate of which the outer periphery portion is unprocessed, comprising amorphous glass material or crystallized glass material having the following composition: 65 wt. % to 85 wt. % of SiO 2 , 3 wt. % to 15 wt. % of Al 2 O 3 , 0 wt. % to 12 wt. % of MgO, 0 wt. % to 10 wt. % of TiO 2 , 3 wt. % to 12 wt. % of Li 2 O, 0 wt. % to 10 wt. % of ZnO, 0 wt. % to 5 wt. % of P 2 O 5  and 0 wt. % to 10 wt. % of ZrO 2 .  
     
     
         7 . A glass substrate of which the outer periphery portion is unprocessed, comprising amorphous glass material or crystallized glass material having the following composition: 45 wt. % to 60 wt. % of SiO 2 , 12 wt. % to 25 wt. % of Al 2 O 3 , 12 wt. % to 25 wt. % of MgO, 0 wt. % to 12 wt. % of TiO 2 , 0 wt. % to 12 wt. % of Li 2 O, 0 wt. % to 10 wt. % of ZnO, 0 wt. % to 5 wt. % of P 2 O 5 , 0 wt. % to 10 wt. % of ZrO 2 , 0 wt. % to 5 wt. % of Nb 2 O 5 , 0 wt. % to 5 wt. % of Ta 2 O 5  and 0 wt. % to 5 wt. % of Y 2 O 3 .  
     
     
         8 . A glass substrate of which the outer periphery portion is unprocessed, comprising amorphous glass material having the following composition: 50 wt. % to 69 wt. % of SiO 2 , 0 wt. % to 15 wt. % of B 2 O 3 , 4 wt. % to 25 wt. % of Al 2 O 3 , 2 wt. % to 7 wt. % of Li 2 O, 0 wt. % to 14 wt. % of Na 2 O, 0 wt. % to 18 wt. % of K 2 O, 0 wt. % to 6 wt. % of CaO, 0 wt. % to 3 wt. % of Ta 2 O 5 , 0 wt. % to 6 wt. % of BaO, 0 wt. % to 6 wt. % of MgO, 0 wt. % to 6 wt. % of SrO, 0 wt. % to 6 wt. % of ZnO.  
     
     
         9 . A manufacturing method for a glass substrate of which the outer periphery portion is unprocessed, characterized in that a first lapping process, a second lapping process, a polishing process and a washing process are carried out after a press molding process is carried out so as to compress glass between an upper mold and a lower mold without regulating the edge surface of the outer periphery portion of the glass and, then, a crystallization process or an annealing process is carried out.  
     
     
         10 . A manufacturing method for a glass substrate of which the outer periphery portion is unprocessed, characterized in that a center of gravity coring process wherein a center hole is created using the center of gravity as the center of the hole is carried out and a first lapping process, a precision inner periphery edge surface process, an inner periphery edge surface polishing process, a second lapping process, a polishing process and a washing process are carried out after a press molding process is carried out so as to compress glass between an upper mold and a lower mold without regulating the edge surface of the outer periphery portion of the glass and, then, a crystallization process or an annealing process is carried out.