Roofing shingle with polymer film backing

Abstract

A roofing shingle is a composite sheet which includes a roofing substrate having a front side and a back side. An asphalt material impregnates the substrate and coats at least the front side of the substrate. A polymer film is attached to the back side of the substrate and forms a back surface of the roofing shingle. The polymer film was applied to the substrate in the form of a film. The roofing shingle does not include backdust on the back surface. The composite sheet is formed into the size and shape of the roofing shingle. A method of manufacturing roofing shingles includes continuously supplying a roofing substrate having a front side and a back side. An asphalt material is applied to the substrate so that it impregnates the substrate and coats at least the front side of the substrate. A composite sheet is produced by providing a polymer film and attaching the polymer film to the back side of the substrate in a manner that avoids applying backdust to the substrate so that the polymer film forms a back surface of the composite sheet. The composite sheet is cut into roofing shingles while maintaining the back surface free of backdust.

1 . A roofing shingle which is a composite sheet comprising:
 a roofing substrate having a front side and a back side;   an asphalt material impregnating the substrate and coating at least the front side of the substrate; and   a polymer film attached to the back side of the substrate and forming a back surface of the roofing shingle, the polymer film having been applied to the substrate in the form of a film;   the roofing shingle not including backdust on the back surface;   the composite sheet being formed into the size and shape of the roofing shingle.   
   
   
       2 . The roofing shingle of  claim 1  wherein the polymer film is attached to the substrate with substantially none of the asphalt material between the film and the substrate. 
   
   
       3 . The roofing shingle of  claim 2  wherein the polymer film is attached to the substrate by an adhesive. 
   
   
       4 . The roofing shingle of  claim 2  wherein the polymer film is attached to the substrate by the surface of the film having been softened so that it adheres to the substrate. 
   
   
       5 . The roofing shingle of  claim 1  wherein the asphalt material is also disposed on the back side of the substrate, and the asphalt material adheres the polymer film to the substrate. 
   
   
       6 . The roofing shingle of  claim 1  further comprising roofing granules applied to the asphalt material coating the front side of the substrate. 
   
   
       7 . The roofing shingle of  claim 1  consisting of the substrate, the asphalt material, the polymer film, optionally roofing granules, and optionally adhesive. 
   
   
       8 . The roofing shingle of  claim 1  wherein the substrate is a relatively lightweight substrate weighing not more than about 1.6 lb/100 ft 2 , the polymer film having sufficient strength to maintain the strength of the roofing shingle with the lightweight substrate. 
   
   
       9 . The roofing shingle of  claim 1  wherein the polymer film has a thickness within a range of from about 0.05 mil to about 10 mils. 
   
   
       10 . The roofing shingle of  claim 1  wherein the polymer film has a thickness within a range of from about 10 mils to about 35 mils. 
   
   
       11 . The roofing shingle of  claim 1  wherein the polymer film is made from a polyolefin, a polyester, or a blend thereof. 
   
   
       12 . A method of manufacturing roofing shingles comprising:
 continuously supplying a roofing substrate having a front side and a back side;   applying an asphalt material to the substrate so that it impregnates the substrate and coats at least the front side of the substrate;   producing a composite sheet by providing a polymer film and attaching the polymer film to the back side of the substrate in a manner that avoids applying backdust to the substrate so that the polymer film forms a back surface of the composite sheet; and   cutting the composite sheet into roofing shingles while maintaining the back surface free of backdust.   
   
   
       13 . The method of  claim 12  wherein the polymer film is attached to the substrate with substantially none of the asphalt material between the film and the substrate. 
   
   
       14 . The method of  claim 13  wherein the polymer film is attached to the substrate by an adhesive. 
   
   
       15 . The method of  claim 13  wherein the polymer film is attached to the substrate by softening the surface of the film so that it adheres to the substrate. 
   
   
       16 . The method of  claim 12  wherein the asphalt material is also disposed on the back side of the substrate, and the asphalt material adheres the polymer film to the substrate. 
   
   
       17 . The method of  claim 12  further comprising embedding roofing granules in the asphalt material coating the front side of the substrate. 
   
   
       18 . The method of  claim 12  consisting of supplying the substrate, applying the asphalt material, attaching the polymer film, optionally applying roofing granules to the asphalt material coating the front side of the substrate, and optionally using an adhesive to attach the film. 
   
   
       19 . The method of  claim 12  wherein the substrate supplied is a relatively lightweight substrate weighing not more than about 1.6 lb/100 ft 2 , and the polymer film attached has sufficient strength to maintain the strength of the roofing shingle with the lightweight substrate. 
   
   
       20 . The method of  claim 12  wherein the polymer film which is attached has a thickness within a range of from about 0.05 mil to about 10 mils. 
   
   
       21 . The method of  claim 12  wherein the polymer film which is attached has a thickness within a range of from about 10 mils to about 35 mils. 
   
   
       22 . The method of  claim 12  wherein the polymer film is made from a polyolefin, a polyester, or a blend thereof.