Durable water repellent

Durable water repellent, or DWR, is a coating added to fabrics at the factory to make them water-resistant (hydrophobic).

The advantages of CVD include reducing the use of environmentally harmful solvents; requiring less DWR; and an extremely thin waterproof layer that has less effect on the natural look and feel of the fabric.

Some researchers have suggested that the use of PFAS in water-repellent clothing is over-engineering, and comparable performance can be achieved using specific silicon- and hydrocarbon-based finishes.

[1][2] Certain types of fabrics need to be re-treated to maintain water-repellency, as fluoropolymers decompose over time when exposed to water and chemicals.

[3] Washing the garment with harsh detergents usually accelerates DWR loss; in addition, soaps often leave a residue which attracts water and dirt.

A shiny spherical drop of water on blue cloth
Fluorine-containing durable water repellent makes a fabric water-resistant.
Top part of the fabric has been ironed after re treatment washing and this heat application has revitalized the repellency of water. Bottom part of the fabric has not been ironed after re treatment washing and the water is still wetting out the fabric.