Film with detachably covered vent hole

摘要

A plastic film has a vent hole with a removable cover, and with a perimeter hole thicker than the remainder of the film. Also disclosed is a plastic film / plastic film manufacturing, in which the appropriate size of a vent hole with a removable cover, is determined from certain characteristics of a product to be stored. Also disclosed is a plastic film making apparatus / method in which a vent hole with a removable cover is formed by the melting of a portion of the film.