Patent ID: 9309035
Filing Date: 2016-04-12
CPC Classification: B65D

Claim Text:
1. A self-standing liquid package bag comprising: two front and rear laminate plastic films integrally defining a bag body portion and a flat film valve portion, each film including an oriented base film layer and a sealant layer laminated on at least one surface of the base film layer; the flat film valve protruding from an upper part of a side edge of the bag body portion, the flat film valve having a fusion portion and a non-fusion portion such that the flat film valve retains a self-sealing one-way function, the fusion portion being opposed inner sealant layers of the front and rear laminate plastic films fused to one another at peripheral parts of the flat film valve other than base end sides thereof, the non-fusion portion being a pouring path for a liquid; a wet-treated layer provided on the pouring path of the flat film valve and a part of the fusion portion adjacent to the pouring path; and a self-standing bottom portion is provided at a bottom of the bag body portion, wherein wherein the front laminate plastic film is a high-nerve film having a nerve of not less than 40 mN but not more than 600 mN, the rear laminate plastic film is a low-nerve film having a nerve of not less than 10 mN but less than 40 mN, and when liquid is poured by a tilting of the bag body portion, a negative pressure is generated inside the bag body portion such that inner surfaces of the laminate plastic films closely adhere to each other in a wetted state to retain the liquid in the pouring path and to simultaneously prevent ambient air from entering the bag body portion.