METAL FOIL LAMINATES AND CONTAINERS MADE FROM THEM

摘要

Heat-bondable laminates of polyester (2) bonded to one surface of a metal (aluminium) foil (3) the other surface of which is bonded to a polyolefin heat-bondable layer (4). Laminates of this type are used to make food containers (1) to replace metal cans which are sterilized at 125 DEG C. The heat-bondable layer used hitherto has been high density polyethylene which has a melting point too close to 125 DEG C. and gives only barely adequate tear strength and impact resistance. The laminates of this invention use instead of the polyethylene, a sequential copolymer of propylene with 12 to 30% by weight ethylene and containers made from them achieve better tear strengths and impact resistances and can be sterilized at temperatures as high as 140 DEG C.