Patent ID: 6960392

Claim:
A multilayer structure comprising a metal layer or a metallized-substrate layer ( 5 ) and a binder layer ( 6 ) comprising polypropylene, extrusion-coated at a rate of more than 100 m/min. onto the metal or metallized-substrate layer, said layers ( 6 , 5 ) being made non-delaminable by heat treating the said structure to a temperature above the melting point of the binder layer ( 6 ), and a polypropylene layer ( 2 ) having a melting point above the melting point of the binder, the binder layer ( 6 ) being sandwiched between the metal layer or metallized-substrate layer ( 5 ) and the polypropylene layer ( 2 ), wherein said structure is peelable between binder layer ( 6 ) and polypropylene layer ( 2 ), and said binder layer ( 6 ) comprises by weight: 5 to 30% of a copolymer (A) based on ethylene and one or more comonomers chosen from the group consisting of carboxylic acid esters, vinyl esters and dienes; 40 to 93% of a stretchable polypropylene (B), stretchability being defined as the ability of a rod extruded at a temperature of between 190° C. and 240° C. and pulled at a pull rate of between 50 and 250 m/min. without breaking; 2 to 30% of an additional polypropylene (C) functionalized by an unsaturated carboxylic acid anhydride; the MFI of the composition being between 10 and 50 g/10 min. at 230° C./2.16 kg.