Q: What is the difference between coated and laminated waterproof zippers?
Coated zippers have a polymer, usually polyurethane, applied directly to the tape as a liquid or paste and then cured. The coating is thin, follows the weave and adds relatively little bulk, which suits lightweight shells and soft trims. Typical hydrostatic values fall in the 3,000 to 10,000 mm range, depending on coat weight and the number of passes.
Laminated zippers bond a separate TPU film to the tape with heat and adhesive. The film is uniform and pinhole-free, so performance is higher, commonly 10,000 to 20,000 mm and sometimes more, and it is more consistent across the roll. The trade-off is stiffness, thickness and cost, plus a delamination risk if the tape is over-pressed or repeatedly dried at high temperature.
Choose coating for light fashion outerwear, packable jackets and cost-sensitive programs. Choose lamination for technical shells, expedition wear and applications where the zipper must match a laminated shell fabric. In both cases, specify adhesion after washing and flex fatigue, because a barrier that survives the lab but separates in the warehouse is a warranty problem, not a specification win.