ePTFE Pressure-Relief Balanced Breathable Membrane, IP68, Rapid Pressure

Water ingress into sealed housings, condensation and fogging, and internal/external pressure differentials can lead to device failure or performance degradation. There is a need to balance protection with breathability/sound transmission.

With the ePTFE Pressure-Relief Balanced Membrane – IP68 Fast Pressure Equalization, Customizable, we achieve IP-level protection while maintaining breathability/sound transmission. We support custom die-cutting, adhesive backing, and specifications tailored to your structure.

Shenzhen Sandeli Precision Technology Co., Ltd. produces ePTFE Pressure-Relief Balanced Membranes using expanded polytetrafluoroethylene microporous film as the substrate. Through precise control of pore size and porosity, the membrane achieves dynamic pressure balancing between the interior and exterior of sealed cavities. When pressure differentials occur due to temperature changes, altitude variations, or internal heating, the membrane allows gas molecules to exchange freely, rapidly eliminating pressure differentials, while blocking water, dust, and salt spray ingress, with protection ratings up to IP67/IP68. The product is available in roll stock, sheet stock, and die-cut with adhesive backing, widely used in sealed cavity applications requiring internal/external pressure balancing, such as automotive electronics, outdoor communications, power batteries, and LED lighting fixtures.

Sandeli provides full-process services for customers in automotive, communications, new energy, and other industries, from pressure equalization solution evaluation and airflow rate selection to die-cut prototyping. We can collaborate with customers on reliability testing including thermal cycling, salt spray, and water immersion. Regular specifications can be sampled within 3 working days, and custom pressure-relief solutions within 5 working days. For cavity pressure equalization and breathable solution selection needs, please contact our engineering team to discuss specific operating parameters.

• Rapid Pressure Equalization to Prevent Condensation
  : The ePTFE microporous membrane's airflow rate can be customized from 500 to 5000 ml/min/cm² @ 70 mbar as needed, and internal/external pressure differentials can be balanced within seconds, effectively preventing condensation short-circuit failures caused by moisture ingress due to negative pressure.
• Waterproof and Dustproof Without Compromise
  : Maintains IP67/IP68 protection while allowing pressure equalization, with hydrostatic pressure ≥80kPa, and passes 72-hour salt spray testing with no penetration, suitable for high-humidity and high-salt environments such as automotive engine compartments and coastal base stations.
• Wide Temperature Range and Long Service Life
  : Temperature resistance from -40°C to 125°C. The microporous structure of the membrane remains stable and undeformed under thermal cycling shock, with service life covering the full life cycle requirements of automotive components.
• Flexible Die-Cutting Adaptability
  : External dimensions from 2mm to 120mm, with tolerances controlled within ±0.1mm. Can be laminated with PET support layers, non-woven fabric liners, or acrylic/silicone adhesive layers to meet the high-efficiency feeding requirements of automated assembly lines.

• Automotive Electronics
  Pressure-relief balanced protection for ECU control units, headlight and taillight assemblies, millimeter-wave radar housings, and ABS/ESP controller cavities to prevent seal failure due to thermal shock.
• Power Batteries
  Battery pack pressure relief and balancing valve components, maintaining internal/external pressure equilibrium during cell charge/discharge thermal expansion and contraction, preventing housing deformation or sealing ring stress fatigue.
• Outdoor Communications & Sensors
  Pressure-relief breathable protection for 5G base station filter cavities, outdoor surveillance cameras, and environmental sensor housings, addressing pressure differentials caused by day-night temperature variations and altitude changes.
• LED Lighting Fixtures
  Cavity protection for high-power outdoor LED modules, expelling internally generated expanding gases to prevent lamp housing gaskets from being pushed out or water vapor ingress causing fogging.