Method for producing polypropylene films

Abstract

The invention relates to a method for producing a biaxially oriented polypropylene film including at least one layer, which is constructed from propylene polymer B and a propylene polymer that has been recycled once. The film is used in capacitors.

1 .- 19 . (canceled) 
     
     
         20 . A biaxially oriented polypropylene film comprising at least one layer, wherein the film is constructed from virgin propylene polymers and contains 0.5 to 40% by weight of at least one polypropylene polymer that has been recycled once and no polymer that has been recycled multiple times. 
     
     
         21 . The film as recited in  claim 20 , wherein the film comprises at least one cover layer that includes 98-100% by weight of a virgin propylene polymer. 
     
     
         22 . The film as recited in  claim 20 , wherein the film includes a cover layer on both sides thereof, each of which includes 98-100% by weight of a virgin propylene polymer. 
     
     
         23 . The film as recited in  claim 20 , wherein the film is metallised on one surface. 
     
     
         24 . A process to manufacture a capacitor which comprises utilizing the film as claimed in  claim 20 . 
     
     
         25 . The film as claimed in  claim 20 , wherein the film is a dielectric film. 
     
     
         26 . The film as claimed in  claim 20 , wherein the film is an electroinsulating film. 
     
     
         27 . A capacitor which comprises the dielectric film as  claim 25 . 
     
     
         28 . A biaxially oriented polypropylene film for use as a dielectric film or electroinsulating film comprising at least one layer, wherein the film is constructed from virgin propylene polymers and contains 0.5 to 40% by weight of at least one polypropylene polymer that has been recycled once and no polymer that has been recycled multiple times.