Air-admittance device and method for making same

• US 7,503,461 B1
• Filed: 06/16/2004
• Issued: 03/17/2009
• Est. Priority Date: 05/13/2002
• Status: Expired due to Fees

• Current Assignee: United States Of America As Represented By The Secretary Of The Air Force
• Original Assignee: United States Of America As Represented By The Secretary Of The Air Force
• Inventors: Wapner, Phillip G., Hoffman, Wesley P.
• Primary Examiner(s): Weaver; Sue A
• Application Number:
  US10/874,006
• Time in Patent Office: 1,735 Days
• Field of Search: 215/11.5, 215/903, 215/261, 215/902, 220/745, 220/913, 220/203.11, 220/203.29, 206/550
• US Class Current: 215/11.5
• CPC Class Codes: A61J 11/02 with means for supplying air
• CPC Class Codes: A61J 9/04 with means for supplying air
• CPC Class Codes: B29C 67/202 comprising elimination of a solid or a liquid ingredient
• CPC Class Codes: Y10S 215/902 Vent
• CPC Class Codes: Y10S 220/913 Ventilated container

Abstract

There are provided methods for fabricating devices for admitting air to a closed container while preventing passage of a water-based fluid therethrough. These devices comprise a plurality of hydrophobic capillaries or a hydrophobic reticulated microporous material. The devices comprising hydrophobic capillaries are fabricated by a variety of techniques, such as those employing extrusion, pultrusion, fugitive mandrel removal or a combination of these techniques. The devices comprising hydrophobic reticulated microporous material are fabricated by techniques such as foaming, sintering, template replication, incorporation of sacrificial particles or a combination of these techniques.

Claims

1. A food or beverage container having a water-based fluid, a partial vacuum and a plurality of air-admittance capillaries, wherein each air-admittance capillary has a hydrophobic interior surface and at least one cross-sectional dimension in the range of 0.1 to 80 microns, wherein said air-admittance capillaries admit air into the container while preventing passage of a water-based fluid therethrough.

2. The container of claim 1 wherein said air-admittance capillary has a constant axial diameter.

3. The container of claim 1 wherein said air-admittance capillary is rectangular.

4. The container of claim 1 wherein said air-admittance capillary has a cross-sectional dimension in the range of 1 to 50 microns.