THIN FLEXIBLE ONE-WAY VALVE, PACKAGING INCLUDING THE SAME, AND METHOD OF MAKING THE SAME

摘要

A one-way valve is mounted over a vent hole in a flexible package to enable gases within the package to vent. The valve has a flexible base layer, a flexible cover layer and a layer of silicone oil interposed therebetween. Each layer has an opposed pair of side edges and are same shape and size. The cover layer is thinner than the base layer and is fixedly secured to the base layer along respective contiguous portions of the side edges of those layers to form a channel therebetween. The ends of the channel are openable. The oil layer is located in the channel between the base layer and the cover layer and over the hole. It forms a bond to hold the cover layer onto the base layer to close the hole until pressure within the package causes the bond to break, whereupon the cover layer to lift ups and opens the valve. Methods of making the package and valve are also disclosed.