Stand-up plastic storage bag with reinforced bottom gusset

Abstract

A stand-up plastic food storage bag having two bottom gusset walls and a folding seam defining abutment of the front bottom gusset wall to the rear bottom gusset wall. There are gusset wall reinforcement layers on an external surface of the bottom gusset walls, and these reinforcement layers terminate at least about 0.25 cm away from the folding seam, and do not cover the folding seam, so they do not significantly interfere with folding the seam when collapsing the bag into its storage condition. A method for forming such stand-up plastic food storage bags by coextruding a monolayer plastic panel film and two monolayer plastic gusset floor reinforcement layers, wherein the monolayer plastic gusset floor reinforcement layers comprise two parallel strips spaced apart by at least about 0.25 cm on the panel film, lengthwise in a direction of coextrusion, followed by folding the monolayer plastic panel film lengthwise to form a lengthwise fold line between the two monolayer plastic gusset floor reinforcement layers, forming a gusset in the area of the lengthwise fold line, forming seals in the plastic panel film in a direction perpendicular to the lengthwise fold line to define individual bag segments, and cutting the plastic panel film at the seals to form individual stand-up plastic food storage bags.