摘要 |
A pressure relief valve includes a flexible sheet bonded, except for a series of adhesive-free areas and channels therebetween, to a container having one or more holes in communication with said adhesive-free areas. The adhesive, preferably pressure-sensitive adhesive, is printed on the sheet in a fashion which, when bonded to the container, forms the adhesive-free areas and channels. When a gas pressure, as for example, derived from food generated gases, builds up within the container, the force of the gas exerted on the flexible sheet causes the sheet to bulge, thereby forming a cavity over the adhesive-free area. The gas then seeps through any series of channels in communication with said cavity and is released to the atmosphere. After the internal gas pressure has been relieved, the flexible sheet returns to its original position (flush against the container) thereby preventing the ingress of atmospheric gases.
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