Chemical reinforcing holders for glass substrate

Abstract

The present invention provides a holder that prevents a glass substrate from deforming during a chemical reinforcing process. The holder includes supporting members, each of which has a plurality of supporting concave portions. The supporting members are formed from a flat plate having a constant thickness so as not to have a portion having high thermal capacity. When the glass substrate is cooled, a thermal stress is not applied to the glass substrate.

What is claimed is:  
     
         1 . A holder for holding glass substrates for an information recording medium and for immersing the glass substrates in a heated chemical reinforcing liquid, the holder comprising: 
 a frame; and    a plurality of supporting members mounted on the frame, wherein each of the supporting members has a plurality of supporting concave portions for receiving outer edges of the glass substrates, respectively, and wherein thickness of the supporting members is constant.    
     
     
         2 . The holder according to  claim 1 , wherein the supporting members are plates having one edge formed with serrate portions including the plurality of supporting concave portions.  
     
     
         3 . The holder according to  claim 1 , wherein each of the supporting members is a line member which is bent so that the supporting concave portions are formed.  
     
     
         4 . The holder according to  claim 1 , wherein each of the supporting members has a ridgeline which defines the supporting concave portions, and wherein the ridgeline is chamfered.  
     
     
         5 . The holder according to  claim 4 , wherein the ridgeline is chamfered by barrel polishing.  
     
     
         6 . The holder according to  claim 1 , wherein the glass substrate is held vertically and the supporting members include: 
 a first supporting member which contacts with a first position of the outer edge of each glass substrate;    a second supporting member which is provided so as to be separated by a predetermined distance from the outer edge of the glass substrate in a second position separated from the first position of the glass substrate by 160 to 180° in a circumferential direction of the glass substrate with respect to the center of the glass substrate; and    a third supporting member for supporting the lower end of each glass substrate.    
     
     
         7 . The holder according to  claim 6 , wherein the predetermined distance is set at 0.1 to 0.5 mm at normal temperature.  
     
     
         8 . The holder according to  claim 1 , wherein the frame includes two side plates, each of which has a plurality of slits, and a connecting member for connecting the two side plates, and wherein both ends of the supporting members are inserted into the plurality of slits of the two side plates, respectively.  
     
     
         9 . The holder according to  claim 8 , wherein one end of each of the supporting members is fixed to one of the two side plates, and the other end of each of the supporting members is mounted on the other side plate movably.  
     
     
         10 . The holder according to  claim 1 , wherein each of the plural supporting members is formed so that the supporting concave portions are arranged in a plane.  
     
     
         11 . The holder according to  claim 1 , wherein the chemical reinforcing liquid contains second ions which have an ion radius larger than an ion radius of first ions existing in a surface layer of each of the glass substrates, and the holder is used to exchange the first ions with the second ions and chemically reinforce the glass substrates.  
     
     
         12 . A holder for immersing a glass substrate in a chemical reinforcing liquid, the holder comprising: 
 a frame;    a first supporting plate mounted on the frame, the first supporting plate having a first serrate portion that defines a first concave portion for receiving a first portion of the glass substrate;    a second supporting plate mounted on the frame, the second supporting plate having a second serrate portion that defines a second concave portion for receiving a second portion of the glass substrate; and    a third supporting plate mounted on the frame, the third supporting plate having a third serrate portion that defines a third concave portion for receiving a bottom portion of the glass substrate.    
     
     
         13 . The holder according to  claim 12 , wherein the third supporting plate is thicker than the first and second supporting plates.  
     
     
         14 . The holder according to  claim 13 , wherein the first, second and third supporting plates have ridgelines that defines the relating concave portions, respectively, and the ridgelines are chamfered.  
     
     
         15 . The holder according to  claim 12 , wherein the first and second supporting members are separated by 160 to 180° in a circumferential direction with respect to the center of the glass substrate.  
     
     
         16 . The holder according to  claim 12 , wherein the third supporting member is separated from the first and second supporting members by 80 to 90° in a circumferential direction with respect the center of the glass substrate.  
     
     
         17 . The holder according to  claim 12 , wherein the frame is connected with the first, second and third supporting members so as to allow thermal expansion of the first, second and third supporting members.  
     
     
         18 . A holder for immersing a glass substrate in a chemical reinforcing liquid, the holder comprising: 
 a frame:    a first supporting wire mounted on the frame, the first supporting wire having a first serrate portion that defines a first concave portion for receiving a first portion of the glass substrate;    a second supporting wire mounted on the frame, the second supporting wire having a second serrate portion that defines a second concave portion for receiving a second portion of the glass substrate; and    a third supporting wire mounted on the frame, the third supporting wire having a third serrate portion that defines a third concave portion for receiving a bottom portion of the glass substrate.    
     
     
         19 . The holder according to  claim 18 , wherein the first, second and third serrate portions are formed by bending the first, second and third supporting wires.  
     
     
         20 . The holder according to  claim 19 , wherein the third supporting wire is thicker than the first and second supporting wires.