Antislip sheet material with twisted tapes

Abstract

A sheet of material suitable for roofing or industrial wrapping applications has an anti-skid surface formed by ridges of twisted tapes. The sheet comprises a woven scrim of warp tapes and weft tapes. Some of the tapes are twisted about their longitudinal axis, for example about (25) to (400) revolutions per meter, to form ridges having a height substantially greater than the thickness of the tapes. The ridges impart an anti-skid surface to the sheet. The scrim is bonded to a coating or film to make the sheet waterproof.

1 - 23 . (canceled) 
     
     
         24 . A sheet of material having an anti-skid surface, the sheet of material comprising:
 a first set of tapes generally parallel to each other, wherein the first set of tapes comprise twisted tapes and untwisted tapes;   a second set of tapes generally parallel to each other and perpendicular to the first set of tapes, wherein the tapes of the first set and the tapes of the second set are interwoven with each other to form a scrim; and   a waterproof film bonded to the scrim;   wherein the twisted tapes form a plurality of parallel ridges, wherein the ridges have a height at least five times greater than the thickness of the untwisted tapes, and wherein the ridges form the anti-skid surface of the sheet.   
     
     
         25 . The sheet of material according to  claim 24 , wherein the second set of tapes comprise twisted tapes and untwisted tapes. 
     
     
         26 . The sheet of material according to  claim 24 , wherein each of the twisted tapes are twisted in a range of 25 revolutions per meter and 400 revolutions per meter. 
     
     
         27 . The sheet of material according to  claim 24 , wherein the twisted tapes have a width greater than or equal to 4 mm and less than 6 mm, and wherein the twisted tapes are twisted between about 250 revolutions per meter and about 400 revolutions per meter. 
     
     
         28 . The sheet of material according to  claim 24 , wherein the height of the ridges is between about ten mils and about twenty mils. 
     
     
         29 . The sheet of material according to  claim 24 , wherein at least some of the twisted tapes are laid on top of and follow a same weaving path of at least some of the untwisted tapes. 
     
     
         31 . The sheet of material according to  claim 24 , wherein the waterproof film comprises a high coefficient of friction elastomer. 
     
     
         32 . The sheet of material according to  claim 24 , wherein the waterproof film is bonded to the scrim by lamination. 
     
     
         33 . The sheet of material according to  claim 24 , wherein the waterproof film is bonded to the scrim by thermal bonding. 
     
     
         34 . A sheet of material having an anti-skid surface, the sheet of material comprising:
 a first set of tapes generally parallel to each other, wherein the first set of tapes comprise twisted tapes and untwisted tapes;   a second set of tapes generally parallel to each other and perpendicular to the first set of tapes, wherein the tapes of the first set and the tapes of the second set are interwoven with each other to form a scrim; and   a first extrusion coating on a first side of the scrim; and   a second extrusion coating on a second side of the scrim;   wherein the twisted tapes form a plurality of parallel ridges, wherein the ridges have a height at least five times greater than the thickness of the untwisted tapes, and wherein the ridges form the anti-skid surface of the sheet.   
     
     
         35 . The sheet of material according to  claim 34 , wherein the second set of tapes comprise twisted tapes and untwisted tapes. 
     
     
         36 . The sheet of material according to  claim 34 , wherein each of the twisted tapes are twisted in a range of 25 revolutions per meter and 400 revolutions per meter. 
     
     
         37 . The sheet of material according to  claim 34 , wherein the twisted tapes have a width greater than or equal to 4 mm and less than 6 mm, and wherein the twisted tapes are twisted between about 250 revolutions per meter and about 400 revolutions per meter. 
     
     
         38 . The sheet of material according to  claim 34 , wherein the height of the ridges is between about ten mils and about twenty mils. 
     
     
         39 . The sheet of material according to  claim 34 , wherein at least some of the twisted tapes are laid on top of and follow a same weaving path of at least some of the untwisted tapes. 
     
     
         40 . A sheet of material having an anti-skid surface, the sheet of material comprising:
 a first set of tapes generally parallel to each other, wherein the first set of tapes comprises twisted tapes and untwisted tapes, wherein at least some of the twisted tapes have a plurality of tape revolutions, wherein at least some of the tape revolutions overlies an adjacent tape revolution to form a circular cross-section about a longitudinal axis of the twisted tape, wherein each twisted tape is twisted between 25 revolutions per meter and 400 revolutions per meter; and   a second set of tapes generally parallel to each other and perpendicular to the first set of tapes, wherein the tapes of the first set and the tapes of the second set are interwoven with each other to form a scrim; and   wherein the twisted tapes form a plurality of parallel ridges, wherein the ridges have a height at least five times greater than the thickness of the untwisted tapes, and wherein the ridges form the anti-skid surface of the sheet.   
     
     
         41 . The sheet of material according to  claim 40 , wherein the second set of tapes comprise twisted tapes and untwisted tapes. 
     
     
         42 . The sheet of material according to  claim 40 , further comprising a waterproof film bonded to the scrim. 
     
     
         43 . The sheet of material according to  claim 40 , wherein at least some of the twisted tapes have a width between about 1.5 mm and about 6 mm.