Drysuit Zipper: Materials & Test Standards | YILON 翼隆实业

The drysuit zipper is the single most demanding sealing point on the entire suit. It must be airtight, pressure-resistant, salt-spray resistant, and cold-tolerant. The mainstream solution is a one-piece TPU airtight zipper (#5/#8) with a silicone rubber envelope, achieving IPX8 and 60kPa pressure retention.

Key requirements for drysuit zippers

Airtight: blocks air and water, holding at least 60kPa.
Salt-spray resistance: withstands long-term seawater exposure.
Cold performance: no hardening or cracking at -30°C.
Cycle life: stays sealed through 3000+ open/close cycles.
Flexibility: does not restrict diver movement.

Common materials compared

Material	Advantages	Caveats
TPU	Best all-round: hydrolysis & temperature resistance, elasticity	Higher cost
Silicone	Highly flexible, weather-resistant	Lower strength; needs reinforcement
Nylon + TPU film	Lightweight, flexible	Less effective at high-pressure sealing
Metal	High strength	Heavy, corrodes, not for drysuit pressure sealing

Sealing: one-piece vs traditional tape

One-piece molding: teeth and tape are molded as a single component with no seams — highly reliable sealing.
Traditional tape: sewn + taped, more seams, prone to leakage at needle holes over time.

Standards & testing

IPX8: continuous immersion (depth and duration per agreement).
Sealing pressure: 60kPa pressure-retention test.
Salt-spray test (per ASTM B117).
Cycle life: 3000+ cycles.
Temperature range test: -30°C to 70°C.

YILON: YILON diving products: drysuit envelopes (silicone), #5/#8 TPU airtight zippers, separable circular airtight zippers; custom lengths and colors, sample validation available.

Contact YILON for Guidance