Multilayer oriented film containing polypropylene and co-polyester

Claim 2

An oriented film laminate in which the layers in­clude polypropylene and a co-polyester, characterized in that the polypropylene layer is a homopolymer of propylene or a copolymer of propylene and an alkene monomer having 2, 4, 5 or 6 carbon atoms, the co-polyester layer is the reaction product of the polyesterification of at least three reactants selected from at least one diol and at least one dibasic acid, and the laminate also comprises an adhesive layer of a polar-modified polyolefin located between and bonded to the polypropylene and co-polyester layers, the polar modifier being an acrylate, an acetate, an anhydride, an acid, or an ester, and the orien­tation is either uniaxial or biaxial from 3 to 10 times.

Claim 3

An oriented film laminate as claimed in claim 1, further characterized in that the adhesive layer is a reaction product of an olefin having 2-10 carbon atoms and a modifier selected from methyl acrylate, methyl methacrylate, ethyl acrylate, glycidyl methacrylate, butyl acrylate, 2-hydroxy ethylacrylate, vinyl acetate, maleic anhydride, acrylic acid, maleic acid, methacrylic acid, diethyl maleate, and nonoethyl maleate.

Claim 4

An oriented film laminate as claimed in Claim 1 or 2, further characterized in that the polypropylene layer is a propylene copolymer in which the other alkene monomer is ethylene, butene, pentene, or 1,4 methyl pentene.

Claim 5

An oriented film laminate as claimed in Claim 1, 2, or 3, further characterized in that the polypropylene layer is a propylene-ethylene copolymer having 2-4% of the ethylene component.

Claim 6

An oriented film laminate as claimed in any one of the preceding claims, further characterized in that the poly­propylene layer contains a filler thatinitiates voids to provide opacity when the polypropylene layer is oriented, the filler being calcium carbonate, clay, or an organic filler that is incompatible with the polymer.

Claim 7

An oriented film laminate as claimed in any one of the preceding claims, further characterized in that the co-­polyester layer is the reaction product of three reactants that comprise terephthalic or isothalic acid and ethylene glycol or butylene glycol.

Claim 8

An oriented film laminate as claimed in in any one of the preceding claims, further characterized in that the co-­polyester layer is the reaction product of terephthalic acid, ethylene glycol, and cyclohexanedimethanol.

Claim 9

An oriented film laminate as claimed in in any one of the preceding claims, further characterized in that the co-­polyester layer is coated with with a metal layer of aluminum, copper, silver, or gold.

Claim 10

An oriented film laminate as claimed in in any one of the preceding claims, further characterized in that the outer surface on the polypropylene layer is coated with a layer of polyvinylidene chloride.

Claim 11

10 A process for the preparation of a laminated film having at least three layers and including the steps of ex­truding and stretching a polypropylene layer and a co-poly­ester layer, characterized in that polypropylene particles of a homopolymer of propylene or a copolymer of propylene and an alkene monomer having 2, 4, 5 or 6 carbon atoms, particles of a polar-modified polyolefin, and particles of a co-polyester that is the reaction product of the polyesterification of at least three reactants selected from at least one glycol and at least one dibasic acid, are melted and then extruded sepa­rately and laminated, or extruded together to form the film, and the stretching of the film is from 3 to 10 times in each direction.

Claim 12

10 A process for the preparation of a laminated film having at least three layers and including the steps of ex­truding and stretching a polypropylene layer and a co-poly­ester layer, characterized in that polypropylene particles of a homopolymer of propylene or a copolymer of propylene and an alkene monomer having 2, 4, 5 or 6 carbon atoms, particles of a polar-modified polyolefin, and particles of a co-polyester that is the reaction product of the polyesterification of at least three reactants selected from at least one glycol and at least one dibasic acid, are melted and then extruded sepa­rately and laminated, or extruded together to form the film, and the stretching of the film is from 3 to 10 times in each direction.

Claim 13

A process as claimed in claim 10, further character­ized in that the stretching of the film is 3-10 times in the machine direction and then 5 to 10 times in the transverse direction.

Claim 14

A process as claimed in claim 10, further character­ized in that the stretching of the film is carried out biaxi­ally about 7 times in each direction.

Claim 15

A process as claimed in claim 10, further character­ized in that the the co-polyester layer of the oriented film laminate is corona treated and then coated with a metal layer of aluminum, copper, silver, or gold.