| 摘要 |
A multilayered film exhibiting good transparency, welding resistance, puncture resistance and impact strength having an outer layer selected from the group consisting of: (1) homopolymers of polypropylene, (2) ethylene/propylene copolymers and (3) blends of (a) high density polyethylene and (b) propylene and ethylene block copolymers; an inner layer of a different composition from the outer layer and selected from the group consisting of ethylene and alpha-olefin copolymers, and ethylene and alpha-olefin copolymers blended with low density polyethylene; and a complex intermediate layer joining the outer layer to the inner layer, the complex intermediate layer having a plurality of sublayers defining an upper nucleus B1, a core B2 and a lower nucleus B3, the upper nucleus being a propylene and ethylene copolymer and the lower nucleus being an ethylene copolymer with an ethylene content greater than the upper nucleus. |
