Introduction to breathable water-repellent textiles and their production methods
Type of Breathable textile materials | Methods of producing Breathable textiles
Breathability refers to the ability of a fabric to absorb moisture and release it through the material itself, allowing it to ‘breathe’. Breathable Fabrics transmit body moisture away from the body, thus maximizing comfort and dryness during outdoor activities.
How DWRs Work
DWRs work by increasing the “contact angle” or “surface tension” created when water contacts a textile. Basically, a high contact angle creates a microscopically “spiky” surface that suspends water droplets on the outer fringe of the fabric.
An optimized DWR keeps droplets in a rounded shape—like a dome-shaped bead. The rounder the droplet, the easier it rolls off the fabric. A low contact angle permits droplets to assume a flattering shape, one that can spread out like a splotch, cling to the fabric’s surface and eventually seep into it.
Manufacturers generally measure DWR effectiveness by a spray test. Water is sprayed onto a textile, and the amount that sticks is visually assessed. A score of 90 points indicated that roughly 90% of the fabric has no water sticking to it. The higher the number, the better the performance. The test is then repeated after a number of washings to determine durability.
Test scores and the number of washings is combined to create a rating. For example, a 90/10 rating means the spray test achieved a total of 90 points after 10 washes.
Not all manufacturers publish DWR performance ratings, but here is a basic guide for interpreting any that you find:
- Good: 80 points after 10 washes. This is a basic outerwear finish.
- Excellent: 80 points after 20 washes. Marmot, for example, uses this as its minimum rating for outerwear.
- Superior: 80 points after 50 to 100 washes.