Method for cutting plate-like glass, and cutting device therefor

Abstract

A full body of a glass sheet (G) is cut by forming an initial crack ( 6 a ) on a preset cutting line ( 5 ) of the glass sheet (G) that is supported by a support member ( 2 ( 8 )) from a back surface side of the glass sheet (G), followed by propagating the initial crack ( 6 a ) while passing through the glass sheet from a front surface to the back surface thereof due to a stress generated through localized heating along the preset cutting line ( 5 ) and cooling of a heated region that is formed through the localized heating, the glass sheet (G) being supported by the support member ( 2 ( 8 )) from the back surface side through an intermediation of an elastic sheet (E) having low thermal conductivity.

1 . A method of cutting a glass sheet, the method comprising cutting a full body of the glass sheet by forming an initial crack on a preset cutting line of the glass sheet that is supported by a support member from a back surface side of the glass sheet, followed by propagating the initial crack while passing through the glass sheet from a front surface to the back surface thereof due to a stress generated through localized heating along the preset cutting line and cooling of a heated region that is formed through the localized heating,
 the glass sheet being supported by the support member from the back surface side through an intermediation of an elastic sheet having low thermal conductivity.   
     
     
         2 . The method of cutting a glass sheet according to  claim 1 , wherein the elastic sheet has lower thermal conductivity than the support member. 
     
     
         3 . The method of cutting a glass sheet according to  claim 1 , wherein the elastic sheet comprises an organic sheet. 
     
     
         4 . The method of cutting a glass sheet according to  claim 1 ,
 wherein the glass sheet comprises a band-like glass sheet to be delivered continuously,   wherein the elastic sheet comprises a band-like elastic sheet to be delivered continuously together with the band-like glass sheet,   wherein the preset cutting line extends along a delivery direction of the band-like glass sheet, and   wherein the cutting the full body of the glass sheet comprises continuously cutting a full body of the band-like glass sheet along the preset cutting line.   
     
     
         5 . The method of cutting a glass sheet according to  claim 4 , wherein the support member is driven so as to continuously deliver the band-like glass sheet together with the band-like elastic sheet. 
     
     
         6 . The method of cutting a glass sheet according to claim  claim 4 , wherein the preset cutting line is provided at a position for continuously separating the band-like glass sheet at a center portion in a width direction thereof. 
     
     
         7 . The method of cutting a glass sheet according to  claim 4 , wherein the preset cutting line is provided at positions for continuously cutting off selvage portions formed at both ends of the band-like glass sheet in the width direction thereof. 
     
     
         8 . The method of cutting a glass sheet according to  claim 4 , wherein the band-like glass sheet to be delivered continuously comprises a band-like glass sheet to be delivered after being cooled through an annealing zone of a forming apparatus. 
     
     
         9 . The method of cutting a glass sheet according to  claim 4 , wherein the band-like glass sheet to be delivered continuously is rolled into a roll shape around a roll core while the full body of the band-like glass sheet is being continuously cut along the preset cutting line. 
     
     
         10 . The method of cutting a glass sheet according to  claim 1 , wherein the elastic sheet is cut along with the cutting the full body of the glass sheet. 
     
     
         11 . The method of cutting a glass sheet according to  claim 10 , wherein, when the band-like glass sheet to be delivered continuously is rolled into the roll shape around the roll core while the full body of the band-like glass sheet is being continuously cut along the preset cutting line, the band-like elastic sheet cut along with the cutting the full body of the band-like glass sheet is rolled into the roll shape around the roll core in a state of being overlaid on the band-like glass sheet. 
     
     
         12 . The method of cutting a glass sheet according to  claim 1 , wherein retaining members are arranged on a front surface side of the glass sheet so as to be opposed to the support members, respectively, the retaining members being configured to sandwich the glass sheet between the retaining members and the support members. 
     
     
         13 . The method of cutting a glass sheet according to  claim 1 , wherein the glass sheet has a thickness of 200 μm or less. 
     
     
         14 . The method of cutting a glass sheet according to  claim 1 , wherein the localized heating is performed through use of a carbon dioxide laser. 
     
     
         15 . A glass sheet, which is obtained by cutting at least one side thereof by the method according to  claim 1 , the glass sheet having a thickness of 200 μm or less. 
     
     
         16 . A glass sheet, which is obtained by cutting at least one side thereof by the method according to  claim 1 , the glass sheet having a bending strength of a cut surface of 200 MPa or more and a thickness of 200 μm or less. 
     
     
         17 . A glass sheet roll, which is obtained by cutting a glass sheet and rolling the glass sheet into a roll shape around a roll core by the method according to  claim 9 . 
     
     
         18 . A glass sheet, comprising an organic layer formed on at least one of a front surface, a back surface, and a cut surface thereof, the cut surface being formed by cutting the glass sheet by the method according to  claim 1 . 
     
     
         19 . An apparatus for cutting a glass sheet, the apparatus having a structure in which a full body of the glass sheet is cut by forming an initial crack on a preset cutting line of the glass sheet that is supported by a support member from a back surface side of the glass sheet, followed by propagating the initial crack while passing through the glass sheet from a front surface to the back surface thereof due to a stress generated through localized heating along the preset cutting line and cooling of a heated region that is formed through the localized heating,
 wherein the glass sheet is supported by the support member from the back surface side through an intermediation of an elastic sheet having low thermal conductivity.   
     
     
         20 . The method of cutting a glass sheet according to  claim 2 , wherein the elastic sheet comprises an organic sheet.