the invention presents a new use for modified polypropylene films , wherein the films are cold sealable for heat sensitive packaging operations . the films comprise in the following order : a cold seal cohesive layer , a core layer , and a cold seal release layer comprising a mixture of about 1 to 80 % by weight butene - propylene copolymer and about 99 to 20 % by weight butylene - ethylene copolymer .