Abstract A laminated polypropylene film consisting of a crystalline polypropylene layer having laminated to at least one side thereof a copolymer layer, said copolymer being a random copolymer of propylene and an alpha -olefin having 4 or more carbon atoms or a random copolymer of propylene, an alpha -olefin having 4 or more carbon atoms and ethylene obtained by vapor phase polymerization in the substantial absence of a liquid medium and satisfying the following conditions (1) to (4): (1) the content of an alpha -olefin having 4 or more carbon atoms in the copolymer is 8 to 25 mole %, (2) the content of ethylene in the copolymer is 3 mole % or less, (3) the content of a cold xylene-soluble portion in the copolymer is 15 to 60% by weight, and (4) the content of a boiling n-heptane-insoluble portion in the copolymer is 7% by weight or more. Said laminated film has an excellent low-temperature heat-sealability, an excellent transparency, a low blocking and a good scratch resistance.
A laminated polypropylene film consisting of a crystalline polypropylene layer having laminated to at least one side thereof a layer of a random copolymer of propylene and an α-olefin having 4 or more carbon atoms or a random copolymer of propylene, an α-olefin having 4 or more carbon atoms and ethylene obtained by vapor phase polymerization in the substantial absence of a liquid medium, using the catalyst system which consists essentially of a solid catalyst component, an organoaluminum catalyst and an electron-donating compound, said copolymer satisfying the following conditions (1) to (5): (1) the content of an α-olefin having 4 or more carbom atoms in the copolymer is 10 to 24 mole %, (2) the content of ethylene in the copolymer is 3 mole % or less, (3) the content of a cold xylene-soluble portion in the copolymer is 17 to 50% by weight, (4) the content of a boiling n-heptane-insoluble portion in the copolymer is 7% by weight or more, and (5) Δhaze of the copolymer is 4% or less.
Claim 2
Dependent Claim
171 words
A laminated polypropylene film consisting of a crystalline polypropylene layer having laminated to at least one side thereof a layer of a random copolymer of propylene and an α-olefin having 4 or more carbon atoms or a random copolymer of propylene, an α-olefin having 4 or more carbon atoms and ethylene obtained by vapor phase polymerization in the substantial absence of a liquid medium, using the catalyst system which consists essentially of a solid catalyst component, an organoaluminum catalyst and an electron-donating compound, said copolymer satisfying the following conditions (1) to (5): (1) the content of an α-olefin having 4 or more carbom atoms in the copolymer is 10 to 24 mole %, (2) the content of ethylene in the copolymer is 3 mole % or less, (3) the content of a cold xylene-soluble portion in the copolymer is 17 to 50% by weight, (4) the content of a boiling n-heptane-insoluble portion in the copolymer is 7% by weight or more, and (5) Δhaze of the copolymer is 4% or less.
Claim 3
Dependent Claim
19 words
A laminated polypropylene film according to claim 1, wherein the α-olefin having 4 or more carbon atoms is butene-1.
Claim 4
Dependent Claim
16 words
A laminated polypropylene film according to claim 1, whereis a uniaxially or biaxially stretched lamianted film.
Claim 5
Dependent Claim
17 words
A laminated polypropylene film according to claim 2, which is a uniaxially or biaxially stretched laminated film.