Water droplets on the surface of a woven fabric
If the fluorine-free water-repellent finish on export fabric does not form a continuous film, water penetrates inwards as soon as it lands and the spray rating falls short of the export threshold; if the water-repellent index is chased at any cost, the coating runs thick and the hand turns hard and harsh, and wearing comfort and water repellency become hard to hold together.
Chemi Tech supplies water repellents for export fabric and fluorine-free water-repellent finishing systems, drawn from the water repellent KMWF-102 series; the bath ratio is set by the fibre type, the finishing method and the target spray rating. KMWF-102 is a fluorine-free type, with perfluorinated content that can be held within the detection limit, so the export test passes at the first attempt; KMWF-01 in the same series suits fabric finishing that has to meet a fluorine-free testing specification. Chemi Tech verifies water-repellent performance around the fibre type and the finishing process, and matches the fitted water repellent for the customer.
Advantages of Chemi Tech Water Repellents
Chemi Tech water repellent KMWF-102 series is designed in the fluorine-free direction, with perfluorinated content that can be held within the detection limit, so the export test passes at the first attempt; in addition, the film on the fibre surface is continuous, and water droplets rest on the fabric surface instead of penetrating inwards; moreover, it is compatible in the same bath with softeners and resins, so the finishing process needs no splitting; in addition, the hand stays soft and does not turn hard or harsh, and wearing comfort is not affected.
Industry Pain Points and Solutions
The difficulty in fluorine-free water repellency for export fabric lies in the hard bargain between a water-repellent film and the hand; the consequence is either a spray rating that passes while the hand turns hard, or a hand that holds up while the water repellency falls short.
Water penetrating inwards is a major pain point. With some fluorine-free finishing agents the film is not continuous, water penetrates inwards as soon as it lands, and the spray rating falls short of the export threshold. Chemi Tech recommends dosing the KMWF-102, whose film is continuous, into the finishing bath, so that the film on the fibre surface stays continuous and does not fail early.
Next comes the hardening of the hand. When the coating runs thick the water repellency holds but the fabric turns hard, and wearing comfort drops. KMWF-102 from Chemi Tech is designed to balance water repellency and the hand, with a continuous film that does not turn hard.
Another lies in same-bath compatibility. Export fabric finishing is often run in the same bath as softeners, anti-crease and other auxiliaries; if the auxiliaries are not compatible with one another, both the finishing effect and the hand suffer. Chemi Tech runs same-bath comparisons of KMWF-102 against common auxiliaries, and the finishing process needs no splitting.
Typical Operating Conditions and Verification
Customer: an outdoor fabric finishing company in Fujian, for the fluorine-free water-repellent finishing line for export fabric.
At this plant the fabric took up moisture after the fluorine-free finish, the spray rating fell short, the hand turned hard, and customers reported lower wearing comfort. The solution Chemi Tech water repellent gave for the situation was: taking the fibre type and the finishing method into account, choose the KMWF-102 series, and re-calibrate the bath concentration and the curing conditions. After the finishing line was adjusted, the spray rating came back within the export threshold, the hand returned to soft, and the water-repellent performance held steady.
Frequently Asked Questions
For export fabric treated with a fluorine-free water repellent, will the water-repellent performance and the wash durability be affected?
It does need watching, since a few fluorine-free formulations form a thin film, and the water repellency and wash durability are limited with it. KMWF-102 is designed in the fluorine-free direction, with a continuous film on the fibre surface, and the spray rating stays within the threshold after repeated washing. The bath concentration is set by the fibre type and the gram weight, and Chemi Tech gives its recommendation after comparisons of water repellency and fluorine-free testing.