Roofing tile and snow-melting, tiled roof using the same

Abstract

A tile is made of a fire-resistant ceramic, which is obtained by mixing and kneading defatted bran obtained from rice bran and a thermosetting resin, primarily baking the resulting mixture in an inert gas at 700° C. to 1000° C., crushing the resulting product into carbonized powder, mixing and kneading the carbonized powder with a ceramic powder, a solvent and, optionally, a binder to provide a plasticized mixture (ceramic-solvent mixture), pressure-forming the mixture at a compression pressure of 10 MPa to 100 MPa, and heat-treating the resulting compact again in an atmosphere of an inert gas at 500 to 1400° C.

1 . A roofing tile comprising a fire-resistant CRB ceramic, said fire-resistant CRB ceramic being obtained by providing a defatted bran derived from rice bran, mixing the defatted bran with a thermosetting resin comprising at least one resin selected from the group consisting of a phenolic resin, a diaryl phthalate resin, an unsaturated polyester resin, an epoxy resin, a polyimide resin and a triazine resin at a mixing ratio by weight between the defatted bran and the thermosetting resin of 50:50 to 90:10 to form a first mixture, kneading the first mixture, baking the first mixture in an inert gas at a temperature of 700° C. to 1000° C. to form a first compact, crushing the first compact into carbonized powder, mixing the carbonized powder with a ceramic powder, a solvent and a binder to form a plasticized mixture, the ceramic powder being at least one member selected from the group consisting of SiO 2 , Si 3 N 4 , ZrO 2 , Al 2 O 3 , SiC, BN, WC, TiC, a sialon, porcelain clay, feldspar clay and kaolin, the mixing ratio by weight between the carbonized powder and the ceramic powder ranging from 5:95 to 95:5 and the binder being added to the sum of the carbonized powder and the ceramic powder in a mixing ratio by weight therebetween of 1:100 to 50:100, pressure-forming the plasticized mixture at a pressure of 10 to 100 MPa to form a second compact and heat-treating the second compact in an inert gas atmosphere or an atmosphere not containing oxygen at a temperature of from 500° C. to 1400° C.  
   
   
       2 . The roofing tile of  claim 1 , additionally comprising a projection integrally formed therewith for fixing the tile to a cleat.  
   
   
       3 . The roofing tile of  claim 1 , additionally comprising terminal holes provided in the tile for permitting passage of an electric current.  
   
   
       4 . The roofing tile of  claim 1 , additionally comprising an electrical resistor integrally embedded inside the tile for heat generation.  
   
   
       5 . The roofing tile of  claim 4 , wherein the electrical resistor is made of a nichrome wire, an RB ceramic or a CRB ceramic.  
   
   
       6 . The roofing tile of  claim 4 , wherein the electrical resistor is made of an RB ceramic or a CRB ceramic.  
   
   
       7 . The roofing tile of  claim 6 , wherein the electrical resistor is made of a CRB ceramic.  
   
   
       8 . A snow-melting roof comprising a plurality of roofing tiles, each individual roofing tile comprising a fire-resistant CRB ceramic, said fire-resistant CRB ceramic being obtained by providing a defatted bran derived from rice bran, mixing the defatted bran with a thermosetting resin comprising at least one resin selected from the group consisting of a phenolic resin, a diaryl phthalate resin, an unsaturated polyester resin, an epoxy resin, a polyimide resin and a triazine resin at a mixing ratio by weight between the defatted bran and the thermosetting resin of 50:50 to 90:10 to form a first mixture, kneading the first mixture, baking the first mixture in an inert gas at a temperature of 700° C. to 1000° C. to form a first compact, crushing the first compact into carbonized powder, mixing the carbonized powder with a ceramic powder, a solvent and a binder to form a plasticized mixture, the ceramic powder being at least one member selected from the group consisting of SiO 2 , Si 3 N 4 , ZrO 2 , Al 2 O 3 , SiC, BN, WC, TiC, a sialon, porcelain clay, feldspar clay and kaolin, the mixing ratio by weight between the carbonized powder and the ceramic powder ranging from 5:95 to 95:5 and the binder being added to the sum of the carbonized powder and the ceramic powder in a mixing ratio by weight therebetween of 1:100 to 50:100, pressure-forming the plasticized mixture at a pressure of 10 to 100 MPa to form a second compact and heat-treating the second compact in an inert gas atmosphere or an atmosphere not containing oxygen at a temperature of from 500° C. to 1400° C., each individual roofing tile additionally comprising terminal holes containing terminals of a conductive member embedded therein.  
   
   
       9 . The snow-melting roof of  claim 8 , additionally comprising a crosspiece having a plurality of terminals and lead wires connecting said terminals, said crosspiece terminals being inserted in the terminal holes of the tiles to allow the tiles to be electrically connected with one another such that when an electric potential is applied across the plurality of roofing tiles, heat is generated by the conductive members embedded therein to permit the melting of snow.  
   
   
       10 . The snow-melting roof of  claim 8 , wherein the conductive member is made of nichrome wire, an RB ceramic or a CRB ceramic.  
   
   
       11 . The snow-melting roof of  claim 10 , wherein the conductive member is made of an RB ceramic or a CRB ceramic.  
   
   
       12 . The snow-melting roof of  claim 11 , wherein the conductive member is made of a CRB ceramic.  
   
   
       13 . The roofing tile of  claim 1 , wherein the fire-resistant CRB ceramic contains at least one recycled material selected from the group of a recycled RB ceramic, a recycled CRB ceramic and a recycled fire-resistant CRB ceramic.  
   
   
       14 . The snow-melting roof of  claim 8 , wherein the fire-resistant CRB ceramic contains at least one recycled material selected from the group of a recycled RB ceramic, a recycled CRB ceramic and a recycled fire-resistant CRB ceramic.