Abstract: One-way pressure relief valves with structure providing high pressure opening and closing functionality are disclosed. Valves of the types described herein may be applied to a product package with flexible walls, for example a package containing dry roasted coffee, to allow gas to escape from the package while preventing entry of ambient air into the package. The valve structure provides a high-pressure valve which both opens and closes at high pressure internal to the package. The valve structure eliminates or reduces excessive expansion of the flexible-walled package caused by pressure increases within the package and eliminates or reduces excessive contraction or paneling of the flexible-walled package caused by increases in ambient pressure outside the package providing for an aesthetically improved package while also maintaining the quality of the packaged product.

Abstract: One-way pressure relief valves with wetting fluid reservoirs are disclosed. Valves of the types described herein may be applied to a product package, for example a package containing dry roasted coffee, to allow gas to escape from the package while preventing entry of ambient air into the package. A wetting fluid is provided within the valve to facilitate formation of the seal blocking entry of ambient air through the valve and into the product package. The wetting fluid reservoirs hold wetting fluid to limit or prevent leakage of the wetting fluid from the valve providing benefits such as improved application of the valves to the packages, improved retention of the valves to the packages, and appearance improvements resulting from avoidance of leakage of wetting fluid onto the valve and the package to which the valve is attached.

Abstract: One-way pressure relief valves with wetting fluid reservoirs are disclosed. Valves of the types described herein may be applied to a product package, for example a package containing dry roasted coffee, to allow gas to escape from the package while preventing entry of ambient air into the package. A wetting fluid is provided within the valve to facilitate formation of the seal blocking entry of ambient air through the valve and into the product package. The wetting fluid reservoirs hold wetting fluid to limit or prevent leakage of the wetting fluid from the valve providing benefits such as improved application of the valves to the packages, improved retention of the valves to the packages, and appearance improvements resulting from avoidance of leakage of wetting fluid onto the valve and the package to which the valve is attached.