Method for the manufacture of a bituminous coating sheet and such coating sheet

Abstract

A bituminous coating sheet for a base, and a method for the manufacture of a bituminous coating sheet for a base is provided that includes a bitumen-impregnated core material that has been coated with a top-face bitumen and a rear-face bitumen and which has an outermost layer of welding bitumen arranged in zones on a side of the sheet to be adhered to the base. The layer of rear-face bitumen has thereon a layer of a grainy mineral material in a matrix including a thermoplastic polymer. The grainy mineral material layer is between the rear-face bitumen and the outermost layer of welding bitumen and provides a barrier for melted rear-face bitumen when heat energy is applied to the welding bitumen during application of the sheet. Ninety-five percent by weight of the grainy mineral material consists of grains that are smaller than 0.15 mm.

1 . A coating sheet for a base comprising a bitumen-impregnated core material that has been coated with a top-face bitumen and a rear-face bitumen and having an outermost layer of welding bitumen arranged in zones on a side of the sheet to be adhered to the base, the layer of rear-face bitumen having thereon a layer of a grainy mineral material in a matrix including a thermoplastic polymer, said layer being between the rear-face bitumen and the outermost layer of welding bitumen and providing a barrier for melted rear-face bitumen when heat energy is applied to the welding bitumen during application of the sheet, 95% by weight of said grainy mineral material being grains that are smaller than 0.15 mm.  
   
   
       2 . The coating sheet according to  claim 1 , wherein the amount of grainy mineral material constitutes at least 0.3 cm 3  and maximally 200 cm 3  per m 2  of the sheet.  
   
   
       3 . The coating sheet according to  claim 1 , wherein an amount of said grainy mineral material is between about 1 cm 3  and 40 cm 3  per m 2  of said sheet.  
   
   
       4 . The coating sheet according to  claim 1 , wherein an amount of said grainy mineral material is between about 3 cm 3  and 20 cm 3  per m 2  of said sheet.  
   
   
       5 . The coating sheet according to  claim 1 , wherein said coating sheet is configured to be rolled up and unrolled.  
   
   
       6 . The coating sheet according to  claim 1 , wherein said thermoplastic polymer is PVB.  
   
   
       7 . The coating sheet according to  claim 1 , wherein said layer of top-face bitumen carries a sanding on a side opposite said side to be adhered to the base.  
   
   
       8 . The coating sheet according to  claim 1 , wherein 95% by weight of said grainy mineral material are grains that are smaller than 0.045 mm.  
   
   
       9 . The coating sheet according to  claim 8 , wherein said coating sheet is configured to be rolled up and unrolled.  
   
   
       10 . The coating sheet according to  claim 8 , wherein said layer of top-face bitumen carries a sanding on a side opposite said side to be adhered to the base.  
   
   
       11 . The coating sheet according to  claim 9 , wherein said layer of top-face bitumen carries a sanding on a side opposite said side to be adhered to the base.  
   
   
       12 . The coating sheet according to  claim 9 , wherein said thermoplastic polymer is PVB.  
   
   
       13 . A coating sheet for a base comprising a bitumen-impregnated core material that has been coated with a top-face bitumen and a rear-face bitumen and having an outermost layer of welding bitumen arranged in zones on a side of the sheet to be adhered to the base, the layer of rear-face bitumen having thereon a layer of a mixture of a grainy mineral material and a thermoplastic polymer, said layer being between the rear-face bitumen and the outermost layer of welding bitumen and providing a barrier for melted rear-faced bitumen when heat energy is applied to the welding bitumen during application of the sheet, 95% by weight of said grainy mineral material being grains that are smaller than 0.15 mm, said coating sheet being rolled up and unrollable and said layer of top-face bitumen carrying a sanding on a side opposite said side to be adhered to the base.  
   
   
       14 . A method for the manufacture of a bituminous coating sheet for a base, wherein a bitumen-impregnated core material, on which a layer of rearface bitumen has been applied, is caused to contact one or more rotating bodies during the manufacturing process, and wherein welding bitumen is subsequently applied in zones in order to enable, during application of the sheet on the base, the establishment of pressure equalization channels between the layer of rear-face bitumen and the base, said method comprising: 
 providing a layer of a grainy mineral material in a matrix including a thermoplastic polymer;    applying said grainy mineral material layer to the layer of rear-face bitumen on the side that is to be caused to contact the one or more rotating bodies;    applying the welding bitumen in zones on the side provided with said grainy mineral material layer; and    said layer of grainy mineral material providing a barrier for melted rear-faced bitumen when heat energy is applied to the welding bitumen during application of the sheet.    
   
   
       15 . The method according to  claim 14 , wherein the supplied amount of the grainy mineral material and advancement rate of the core material is selected such that the finished product has at least 0.3 cm 3  and maximally 200 cm 3  per m 2  of the sheet.  
   
   
       16 . The method according to  claim 14 , wherein the grainy mineral material layer is applied in a spraying process.  
   
   
       17 . The method according to  claim 14 , wherein the grainy mineral material layer is applied at such distance from the first rotating body that liquid therein is evaporated prior to contact with the first rotating body.  
   
   
       18 . The method according to  claim 14 , wherein the bitumen-impregnated core material and the layer of rear-face bitumen has, when the grainy mineral material layer is applied, a temperature of between 100° C. and 200° C.  
   
   
       19 . The method according to  claim 14 , wherein the supplied amount of the grainy mineral material and advancement rate of the core material is selected such that the finished product has between 1 cm 3  and 40 cm 3  of the grainy mineral material per m 2  of the sheet.  
   
   
       20 . The method according to  claim 14 , wherein the supplied amount of the grainy mineral material and advancement rate of the core material is selected such that the finished product has between 3 cm 3  and 20 cm 3  of the grainy mineral material per m 2  of the sheet.