ePTFE Acoustic Waterproof Membrane , IP68, low insertion loss, customizable.

Shenzhen Sandeli Precision Technology Co., Ltd. produces ePTFE waterproof acoustic membranes using expanded polytetrafluoroethylene microporous film manufactured through a precision stretching process. The membrane thickness is controlled between 0.02mm and 0.15mm, achieving IP67/IP68 waterproof ratings while delivering excellent sound wave transmission performance. The acoustic attenuation is ≤2dB (at 1kHz), ensuring that the pickup and output quality of microphones, speakers, and other acoustic devices remain unaffected by the protective layer. The product is available in roll stock, sheet stock, and custom die-cut with adhesive backing, widely used in consumer and industrial acoustic devices including smartphones, TWS earphones, smart speakers, hearing aids, and walkie-talkies.

Sandeli provides a complete service chain for acoustic device customers, from membrane material selection and acoustic testing to die-cut delivery. We can collaborate with customers on specialized testing and validation, including insertion loss, frequency response curves, and waterproof ratings. Regular specifications can be sampled within 3 working days, and custom dimensions and adhesive layer solutions within 5 working days. For waterproof acoustic solution needs, please contact our engineering team to discuss specific acoustic specifications.

• Waterproof and Acoustic Sound-Permeable in One: The ePTFE microporous membrane blocks liquid water while maintaining an extremely thin structure and low acoustic impedance. Measured insertion loss is ≤2dB @ 1kHz, with no significant acoustic performance degradation after 30 minutes of IPX7 immersion. This solves the protection challenges for acoustic devices in humid, rainy, and submerged environments.
• Ultra-Thin and Highly Flexible: Membrane thickness can be as low as 0.02mm, with excellent flexibility. Suitable for compact installation spaces such as miniature microphones and miniature speakers, without affecting overall structural stack design.
• Broadband Flat Frequency Response: The acoustic attenuation curve remains stable across the 100Hz–10kHz frequency range, with no significant resonance peaks, ensuring frequency response consistency for voice calls and music playback.
• Reliable Adhesive Solutions: Pre-laminated with high-performance acrylic adhesive layer, with bond strength ≥ 8N/25mm (180° peel, stainless steel plate), temperature resistance –40°C to 125°C, with no edge warping or leakage after high-temperature and high-humidity aging tests.

• Smartphones: Waterproof acoustic protection for earpieces, bottom speakers, top microphones, and rear noise-canceling microphone ports, supporting full-device IP68 certification.
• TWS Earphones & Headphones: Protection for sound output ports and pickup ports against sweat and rain, without affecting the pickup accuracy of active noise-canceling (ANC) microphones.
• Smart Wearables: Waterproof acoustic protection for smartwatch microphones/speakers, breathable protection for sports band barometers, and waterproof/earwax protection for hearing aid acoustic ports.
• Industrial & Outdoor Equipment: Microphone waterproof solutions for walkie-talkies, body-worn cameras, outdoor surveillance pickups, and industrial acoustic sensors.

• Sample production based on drawings
• Precision die-cutting
• Adhesive lamination