Abstract The present invention relates to a paper like polymeric film and a method of production thereof, said film being made up of a composition containing at least 5 percent by weight of a polypropylene or an ethylene/propylene copolymer having an ethylene content of 0 - 15 mol percent, 5 - 70 percent by weight of a polyethylene or an ethylene/propylene copolymer having a propylene content of 0 - 30 mol percent and 5 - 50 percent by weight of a finely divided solid inorganic substance having an average particle diameter of 0.1 - 15 Mu , said film having minute internal voids, a rough surface with fine irregularities in a finely fibrillated state, and being oriented in at least one direction, the void content of said film being 40 - 300 c.c./100 g. and wherein the transmittance of light rays therethrough is not higher than 70 percent.
A method according to claim 1 which further contains 5-60 percent by weight of a polystyrene resin.
Claim 2
Dependent Claim
30 words
A method according to claim 1 wherein said inorganic substance is selected from the group consisting of calcium carbonate, calcium oxide, titanium dioxide, silicon dioxide, aluminum oxide and aluminum sulfate.
Claim 3
Dependent Claim
28 words
A method according to claim 2 wherein said polystyrene resin is selected from the group consisting of polystyrene, an acrylonitrile/butadiene/styrene copolymer, an acrylonitrile/styrene copolymer and a butadiene/styrene copolymer.
Claim 4
Dependent Claim
46 words
A method according to claim 1 wherein the average diameter of the minute voids on the surface of the thus-produced polymeric film is 4 to 250 Mu and the depth of the irregularities on the surface of the polymeric film is 0.5 to 10 Mu .
Claim 5
Dependent Claim
12 words
A paper-like polymeric film produced according to the method of claim 1.