DWR

Definition and Overview

DWR stands for Durable Water Repellent and refers to a water-repellent finish that takes into account some performance degradation from washing and wear. It applies a finishing agent to the surface of woven or knitted fabrics to prevent water droplets from spreading and soaking into the fabric.

DWR is not a fabric structure or fiber name, but a function created by post-finishing. It is used on a wide range of materials such as cotton, polyester, and nylon, but the durability of water repellency and the hand feel of the fabric vary depending on the material, finishing method, and conditions of use.

Features

Because it readily repels water droplets, it helps prevent the surface from getting wet and heavy, and helps reduce how easily clothing becomes cold in the rain. Depending on the type of fabric, it may have a smooth touch or a slightly dry appearance.

However, DWR is not a waterproof finish that stops water from passing through under water pressure. Water can still enter during prolonged rainfall or through seams and around zippers, so products that require waterproofness should be designed with the fabric structure and sewing specifications in mind.

• Water repellency is a surface property that repels water droplets.
• Waterproofing is the ability to prevent water from entering.
• Waterproof and breathable refers to a specification that combines waterproofness with the ability to release water vapor from inside the garment.

Main Applications

It is used for items that are exposed to rain or dirt, such as outerwear, blousons, coats, pants, and bags. It is especially sometimes adopted for light clothing in spring and autumn, outdoor wear, sportswear, uniforms, and workwear.

It can be applied from lightweight to heavyweight fabrics, but if only the outer fabric is water-repellent, that does not determine the overall waterproofness or windproofness of the product. It is assembled according to the intended wearing environment, including the lining, interlayer, and water-sealing specifications.

Selection and Handling Notes

When selecting, check not only the initial water repellency, but also performance after washing, changes after friction, the surface hand feel, and compatibility with dyeing. Depending on the application, it is important to evaluate how water beads, behavior near seams, and the required breathability using fabric samples and product prototypes.

During washing, dirt and detergent residue on the surface can make water droplets spread more easily. Follow the care label and the instructions from the fabric supplier, and carefully judge the use of fabric softener and strong friction. If a product's water repellency has decreased, it may be possible to restore it with a compatible re-finishing agent.

During cutting and sewing, the needle holes themselves are not sealed by the water-repellent finish. For products such as rainwear that need to reduce water penetration, seam tape treatment and other seam-sealing measures should be considered separately. Also, high-temperature pressing can affect the hand feel and water repellency, so advance testing is necessary.

Differences from Similar Terms

Water-repellent finish refers broadly to any finish that repels water, while DWR is the name used for a water-repellent finish intended to be durable. However, evaluation conditions for durability and how it is indicated vary by supplier, so it is important not to compare performance by name alone.

C0 water repellency is sometimes used to refer to a water-repellent formulation that does not use specific fluorochemical compounds. DWR is a functional term for durable water repellency and does not directly indicate the chemical type of the finishing agent.

Frequently Asked Questions