C6 DWR
Also known as: C6 fluorocarbon DWR, C6 fluoropolymer
Water-repellent impregnation based on short-chain perfluoro-hexyl compounds — transitional technology between the banned C8 and PFAS-free C0.
Description
C6 DWR (Durable Water Repellent) is based on perfluorinated C6 fluoropolymers (perfluoro-hexyl chains). These were introduced from 2015 as a replacement for the longer C8 chains (perfluoro-octyl), whose key intermediate perfluorooctanoic acid (PFOA) came under the Stockholm POP convention in 2020 and was banned worldwide. C6 compounds degrade in the environment to PFHxA, which bioaccumulates less than PFOA — but is still persistent.
The effect arises from the extremely low surface energy of perfluoro chains: water droplets bead off as spheres (contact angle > 100 degrees), even oil drops are repelled (oleophobic). Application is by padder or spray in the finishing phase, followed by thermal fixation at 150-170 degrees for cross-linking.
Wash fastness of C6 DWR: 20-40 washes at 40 degrees without significant loss of function, then can be reactivated by wash-bath aftertreatment. REACH regulation has since 2023 also restricted C6 compounds; many brands (Patagonia, Fjällräven, Vaude) have therefore already switched to C0 (silicone, wax or dendrimer based). C6 is considered a phase-out technology.
Properties
| Chemistry | Perfluoro-hexyl polymers (C6) |
|---|---|
| Effect | Water and oil repellent, contact angle > 100° |
| Durability | 20-40 washes at 40 °C, reactivable |
| Environmental profile | Phase-out due to PFAS restriction (REACH) |
Related product categories
Sources & references
1- Wikipedia: Durable water repellent Wikipedia — Freie Enzyklopädie https://en.wikipedia.org/wiki/Durable_water_repellent
