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US-12621940-B2 - Multilayer vent assembly

US12621940B2US 12621940 B2US12621940 B2US 12621940B2US-12621940-B2

Abstract

A vent assembly include a membrane stack, the membrane stack including a plurality of membranes and an air gap between adjacent membranes in the plurality of membranes, wherein each membrane in the plurality of membranes includes a non-fluoropolymer and substantially occlude each other in the membrane stack.

Inventors

  • William Kinder
  • Scott Zero

Assignees

  • W. L. GORE & ASSOCIATES, INC.

Dates

Publication Date
20260505
Application Date
20250806

Claims (20)

  1. 1 . A vent assembly comprising a membrane stack, the membrane stack comprising a plurality of membranes and an air gap between adjacent membranes in the plurality of membranes, wherein each membrane in the plurality of membranes comprises a non-fluoropolymer and substantially occlude each other in the membrane stack, wherein at least one membrane of the plurality of membranes has a bubble point of from 0.2 bar to 10 bar.
  2. 2 . The vent assembly of claim 1 , wherein the thickness of each membrane in the plurality of membranes is at least 5 μm.
  3. 3 . The vent assembly of claim 1 , wherein the thickness of each membrane in the plurality of membranes is from 5 μm to 200 μm.
  4. 4 . The vent assembly of claim 1 , wherein each membrane in the plurality of membranes has a mass per area of at least 2 g/m 2 .
  5. 5 . The vent assembly of claim 1 , wherein each membrane in the plurality of membranes has a mass per area of from 2 g/m 2 to 100 g/m 2 .
  6. 6 . The vent assembly of claim 1 , wherein each membrane in the membrane stack has an isopropyl alcohol (IPA) rating of less than 30% IPA/water.
  7. 7 . The vent assembly of claim 1 , wherein each membrane in the plurality of membranes individually comprise polyethylene (PE), polyurethane (PU), polyamide (PA), or polyimide (PI).
  8. 8 . The vent assembly of claim 7 , wherein each membrane in the plurality of membranes individually comprise PE or PU.
  9. 9 . The vent assembly of claim 7 , wherein each membrane in the plurality of membranes comprise expanded PE.
  10. 10 . The vent assembly of claim 7 , wherein each membrane in the plurality of membranes comprise PU.
  11. 11 . The vent assembly of claim 1 , wherein the membrane stack comprises an adhesive layer between adjacent membranes.
  12. 12 . The vent assembly of claim 9 , wherein the adhesive layer comprises a heat activated film (HAF) or a pressure sensitive adhesive (PSA).
  13. 13 . The vent assembly of claim 1 , wherein the vent assembly has a change in airflow through the vent assembly of less than 80% reduction after a water challenge.
  14. 14 . The vent assembly of claim 1 , wherein the vent assembly has a change in water entry pressure (WEP) of less than 80% reduction after a contamination challenge.
  15. 15 . The vent assembly of claim 1 , wherein the airflow through the vent assembly is from 0.05 L/hr.
  16. 16 . The vent assembly of claim 1 , wherein the airflow through the vent assembly is from 0.05 L/hr to 100 L/hr.
  17. 17 . The vent assembly of claim 1 , wherein the plurality of membranes comprises a first membrane, a second membrane and a third membrane and a first air gap is provided between the first membrane and the second membrane and a second air gap is provided between the second membrane and the third membrane.
  18. 18 . The vent assembly of claim 17 , wherein the first membrane, the second membrane and the third membrane each individually comprise PE or PU.
  19. 19 . The vent assembly of claim 1 , wherein each membrane in the plurality of membranes does not comprise a coating.
  20. 20 . The vent assembly of claim 1 , wherein the air gap between adjacent membranes is at least 20 μm.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to U.S. Provisional Application No. 63/680,129, filed Aug. 7, 2024, which is hereby incorporated herein by reference in its entirety for all purposes. FIELD The present disclosure relates to vent assemblies for use with devices, especially to vent assemblies for use with electronic devices, and devices, especially electronic devices, comprising the same. BACKGROUND Electronic devices that comprise acoustic transducers such as speakers and microphones often comprise vents or vent assemblies that protect such acoustic transducers from the contact with contaminants such as particulates or liquids. Such vents or vent assemblies typically occlude an aperture in the housing of the electronic device through which sound travels from or to the speaker or microphone respectively. Additionally, electronic devices also often incorporate pressure vents, which provide similar functionality in that they prevent the ingress of particulates and liquids from entering and damaging sensitive components but are not necessarily required to transmit sound. The materials used to make up the vents or vent assemblies are required to be resistant to the passage of particulates and liquids, especially liquid water, whilst also maximising the transmission of sound through them. Typically, in order to ensure that the interior of the electronic device is adequately protected from particulates and liquids in a manner that is robust to typical device usage, the membrane of the vent or vent assembly is tailored to prevent ingress of particulates and liquids whilst trying to minimise the degradation of these protection properties after the vent assembly is challenged with high water pressure (such as may happen with accidental submersion of the device) or chemical contamination (such as may happen if the device comes into contact with soapy water, e.g.). However, the properties of new electronic devices are required to constantly be improving by the expectations of users whilst also ensuring that these electronic devices become more durable and resistant to damage due to ingress of liquids and particulates. Accordingly, there remains a need for improved vents and vent assemblies that have improved performance, including performance that does not degrade when the vent and vent assemblies are challenged. Furthermore, vents and vent assemblies often use fluoropolymer membranes which belong to a class of materials known as per- or poly-fluoroalkyl substances (PFAS). PFAS materials may provide superior performance, but may be subject to use restrictions as a result of pending legislation in various jurisdictions that may preclude their use in such applications. Accordingly, it is desirable to provide vents and vent assemblies that do not incorporate fluoropolymer membranes and that have comparable performance. The present disclosure is intended at least in part to address at least one of these issues. SUMMARY According to a first aspect there is provided a vent assembly comprising a membrane stack, the membrane stack comprising a plurality of membranes and an air gap between adjacent membranes in the plurality of membranes, wherein each membrane in the plurality of membranes comprises a non-fluoropolymer and substantially occlude each other in the membrane stack. Typically, each membrane in the plurality of membranes is resistant to deformation during a water challenge. The air gap between adjacent membranes in the plurality of membranes may be maintained or substantially maintained during use. Accordingly, each membrane in the plurality of membranes may not be deformed or otherwise moved to contact or touch an adjacent membrane. The thickness of each membrane in the plurality of membranes may be at least 5 μm. The thickness of each membrane in the plurality of membranes may be at least 7 μm. The thickness of each membrane in the plurality of membranes may be at least 10 μm. The thickness of each membrane in the plurality of membranes may be at least 15 μm. The thickness of each membrane in the plurality of membranes may be from 5 μm to 200 μm. The thickness of each membrane in the plurality of membranes may be from 5 μm to 150 μm. The thickness of each membrane in the plurality of membranes may be from 5 μm to 100 μm. The thickness of each membrane in the plurality of membranes may be from 7 μm to 200 μm. The thickness of each membrane in the plurality of membranes may be from 7 μm to 150 μm. The thickness of each membrane in the plurality of membranes may be from 7 μm to 100 μm. The thickness of each membrane in the plurality of membranes may be from 10 μm to 200 μm. The thickness of each membrane in the plurality of membranes may be from 10 μm to 150 μm. The thickness of each membrane in the plurality of membranes may be from 10 μm to 100 μm. The thickness of each membrane in the plurality of membranes may be from 15 μm to 200 μm. The thickness of each membrane in the plur