YKK Waterproof and Water-Repellent Zips – AquaGuard® and AQUASEAL®

Water-repellent or watertight zip: the key difference

YKK water-resistant zips fall into two groups, which YKK itself defines as different product categories. Water-repellent zips keep out rain and splashes but are not hermetic. Watertight zips have a seal between the teeth and stop water even under pressure. The right choice depends on whether the product needs to withstand rain, or immersion and water under pressure. Polkom offers original YKK zips from both groups to manufacturers of apparel, equipment and bags in the EU; we do not manufacture YKK zips.

Comparison of the lines

For AQUASEAL® No. 10, YKK tests every zip individually at a pressure of 0.3 bar before shipment and laser-marks it for traceability; the tape is available in black only (No. 580).

AquaGuard® films

The standard AquaGuard® version has a reversed coil, hidden on the inner side. There are also versions with narrow tape, two-tone tape, a bridge top stop, decorative film and recycled NATULON® tape. Colour numbers are chosen from the YKK colour card.

Care for zips with polyurethane film

• protect from direct sunlight – UV rays can yellow the film;
• wash with the zip closed and do not tumble dry, which can damage the film;
• do not iron the zip;
• for dry cleaning, a petroleum-based solvent is recommended rather than a chlorinated one;
• avoid prolonged contact between two zips of contrasting colours and with vinyl (PVC, PU) to prevent colour transfer;
• during heat bonding, do not move the slider while the film is softened.

Sizes and types

AquaGuard® coil zips are available in sizes No. 3 and No. 5, and the possible types – closed-end, open-end or two-way – depend on the size and the film. AquaGuard® VISLON® covers sizes No. 3, 5 and 8, and AQUASEAL® No. 5 and No. 10. Available combinations of film, type and length are confirmed on enquiry. Also specify the desired slider and puller – on technical jackets they must be easy to grip, even with gloves.

Design limitations

YKK does not recommend AquaGuard® for curved seams, as the slider can cut the tape. Repeated folding can make the film cloudy. A water-repellent zip on its own does not make the product waterproof – taped seams, the storm flap over the zip and the pocket construction matter too. If the product must withstand immersion, choose AQUASEAL® or PROSEAL®.

Construction around the zip

Even the best water-repellent zip is only part of the protection. In technical garments it is usually surrounded by taped seams, an inner placket or an outer storm flap, and the top end is covered by a zip garage. On backpacks the zip is often placed under a flap. Discuss the construction with your technologist at the sampling stage – this way you will choose the right model, size and film.

Colour and look

Laminated tape gives the characteristic technical look of modern outdoor wear. With transparent film, the tape colour shows through and is chosen by number, while with matt coloured film the colour is in the film itself. YKK also offers neon colours, two-tone tape and printed versions that turn the zip into a visible design detail.

Before a series, YKK advises testing the product under real conditions – with the specific fabric, bonding and washing. This is especially important for water-repellent models, where the film reacts to heat, solvents and prolonged contact with other materials.

How to choose

See also YKK VISLON® moulded zips and YKK nylon coil zips, on which the AquaGuard® models are based. Send us a description of the product, size, type, length and colour – minimum quantities depend on the article. All lines are in the YKK zips section.