Heat-resistant roll, production method thereof, and method of producing sheet glass using heat-resistant roll

Abstract

Provide is a heat-resistant roll with improved effectively characteristics, a production method thereof, and a method of producing sheet glass using the heat-resistant roll. A method of producing a heat-resistant roll equipped with a roll portion containing 5 % by weight or more of clay includes: a grinding step (S 101 ) of grinding a roll surface of the roll portion; and a surface treatment step (S 102 ) of performing surface treatment of smoothening the ground roll surface in a wet state.

What is claimed is: 
     
         1 . A millboard comprising 5% by weight or more of clay, wherein:
 the millboard produces disks of a heat-resistant roll;   the heat-resistant roll comprises a roll portion containing 5% by weight or more of clay, a surface part of the roll portion is made denser compared with an inside of the roll portion,   the surface part has an arithmetic average surface roughness Ra measured by a method defined by JIS B 0601-1994 of 5.0 μm or less,   the surface part of the roll portion is made of a material containing 5% by weight or more of clay.   
     
     
         2 . A method of producing the millboard of  claim 1 , comprising:
 mixing the inorganic fiber, the inorganic filler and the clay to prepare an aqueous slurry, the inorganic filler consisting of at least one selected from the group of mica, wollastonite, silica and alumina;   forming the aqueous slurry into a sheet shape; and   drying the sheet.   
     
     
         3 . A method of producing a disk comprising punching out a disk from the millboard of  claim 1 . 
     
     
         4 . A millboard according to  claim 1 , wherein the millboard contains 90% by weight or more of an inorganic fiber, an inorganic filler and the clay in total; and
 the inorganic filler comprises at least one selected from the group of mica, wollastonite, silica and alumina.   
     
     
         5 . A millboard according to  claim 4 , wherein the inorganic filler consists of at least one selected from the group of mica, silica and alumina. 
     
     
         6 . A millboard according to  claim 1 , wherein the millboard contains 90% by weight or more of an inorganic fiber, an inorganic filler and the clay in total; and
 the inorganic filler consists of at least one selected from the group of mica, wollastonite, silica and alumina.   
     
     
         7 . A millboard according to  claim 1 , wherein the surface part of the roll portion of the heat-resistant roll is smoothened such that concavity and convexity formed by original shapes of fine particles or fiber chips constituting the surface part are not identified in a scanning electron microscope picture with  1000  times magnification. 
     
     
         8 . A millboard according to  claim 1 , wherein the roll portion of the heat-resistant roll contains clay in a range of 5 to 75% by weight. 
     
     
         9 . A millboard according to  claim 1 , wherein a maximum height Ry of the surface part of the roll portion of the heat-resistant roll measured by a method defined by JIS B 0601-1994 is 25.0 μm or less. 
     
     
         10 . A millboard according to  claim 1 , wherein a ten-point average roughness Rz of the surface part of the roll portion of the heat-resistant roll measured by a method defined by JIS B 0601-1994 is 25.0 μm or less. 
     
     
         11 . A millboard according to  claim 1 , wherein the surface part of the roll portion of the heat-resistant roll comprises a portion that does not come into contact with a glass ribbon which is being conveyed in a production of sheet glass. 
     
     
         12 . The millboard according to  claim 4 , wherein:
 the inorganic fiber is selected from an aluminum fiber, a mullite fiber, a silica-alumina fiber and a silica fiber, and   the clay is selected from kibushi clay, Gairome clay, bentonite and kaolin.   
     
     
         13 . The millboard according to  claim 4 , wherein the content of the inorganic fiber is in a range of 15 to 40 wt %, the content of the inorganic filler is in a range of 30 to 60 wt %, and the content of the clay is in a range of 15 to 40 wt %. 
     
     
         14 . A disk comprising 5% by weight or more of clay, wherein:
 the disk is used to produce a heat-resistant roll;   the heat-resistant roll comprises a roll portion containing 5% by weight or more of clay, a surface part of the roll portion is made denser compared with an inside of the roll portion,   the surface part has an arithmetic average surface roughness Ra measured by a method defined by JIS B 0601-1994 of 5.0 μm or less,   the surface part of the roll portion is made of a material containing 5% by weight or more of clay.   
     
     
         15 . A disk according to  claim 14 , wherein the disk contains 90% by weight or more of an inorganic fiber, an inorganic filler and the clay in total; and
 the inorganic filler comprises at least one selected from the group of mica, wollastonite, silica and alumina.   
     
     
         16 . A disk according to  claim 14 , wherein the disk contains 90% by weight or more of an inorganic fiber, an inorganic filler and the clay in total; and
 the inorganic filler consists of at least one selected from the group of mica, wollastonite, silica and alumina.