DWR fabric, or Durable Water Repellent fabric, is a type of material treated with a coating to make it water-resistant. While not completely waterproof, it is designed to repel water, keeping the fabric light and dry during outdoor activities. Over time, many outdoor apparel brands have adopted DWR treatments to enhance the functionality of clothing for hikers, climbers, and athletes. However, understanding its durability, safety, and maintenance is key to making the most of it.
DWR fabric refers to materials treated with a water-repellent coating, designed to keep you dry by causing water to bead and roll off rather than soak in.
When choosing garments or gear with DWR, it’s crucial to evaluate its longevity, environmental impact, and how to care for it. Let's explore these aspects.
1. How DWR Fabric is Made?
DWR (Durable Water Repellent) fabric is created by applying a special chemical coating to the surface of textiles, typically outdoor clothing or gear.
This coating is typically made from fluoropolymers1 or newer eco-friendly alternativesc, creating a microscopic layer on the fabric’s surface that is hydrophobic (water-repellent). When water comes into contact with the treated fabric, it forms droplets due to the high surface tension, preventing it from spreading and soaking into the material.
Types of Chemical Coatings
| Aspect | Fluoropolymer-Based Coatings | Eco-Friendly Alternatives |
|---|---|---|
| Common Chemicals | Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS)2. | Fluorocarbon-free treatments, such as paraffin wax3 and silicone. |
| How It Works | Creates a durable, long-lasting water-repellent barrier. | Mimics the water-repellent properties of fluoropolymers without using harmful chemicals. |
| Pros | Highly effective, durable, and widely used in the outdoor industry. | More sustainable and environmentally friendly. |
| Cons | Not environmentally friendly; breaks down into harmful PFCs4 that persist in the environment. | May not be as durable or long-lasting as traditional fluoropolymer coatings. |
Application Process
| Method | Description |
|---|---|
| Spray Application | The coating is sprayed onto the fabric surface. |
| Padding | The fabric is passed through a bath of the chemical solution and then squeezed to remove excess liquid. |
| Curing | The treated fabric is heated to bond the coating to the fibers, ensuring durability. |
2. How long does a DWR coating last?
DWR coatings don’t last forever, even on high-quality gear. Regular use, washing, and environmental exposure gradually reduce their effectiveness. You may notice water no longer beads on the fabric, signaling it's time for maintenance.
The lifespan of a DWR coating depends on usage and care, but most treatments last 6-12 months with proper washing and reproofing.
Modern DWR (Durable Water Repellent) treatments have become slightly less effective compared to those used over five years ago, as they have shifted to PFC-free5 formulas to address environmental concerns.
While these eco-friendly alternatives still provide water repellency, they tend to be less durable than the older, more toxic formulations that contained perfluorinated chemicals. This trade-off reflects the industry's effort to balance performance with sustainability.
Extending the lifespan of DWR coatings
To maintain a DWR coating:
- Proper washing: Use mild detergents to avoid stripping the coating. Harsh cleaners can degrade its performance.
- Heat activation: Many DWR coatings can be revived by tumble drying on low heat or using an iron on a low setting.
- Reproofing products: Reapply DWR sprays6 or wash-in treatments7 designed for outdoor fabrics.
Understanding these steps ensures your gear remains water-repellent for a longer time. Regular maintenance can delay the need for reapplication and keep the fabric functioning like new.
3. Is DWR toxic to humans?
DWR coatings have evolved significantly over time. Early treatments contained long-chain chemicals like PFOA(Perfluorooctanoic Acid) and PFOS(Perfluorooctane Sulfonate), which raised concerns about toxicity and environmental impact. Modern alternatives are less harmful, yet the topic remains a point of discussion for safety-conscious consumers.
Modern DWR treatments are considered safe for humans, but earlier versions with long-chain fluorochemicals posed health risks.
Breaking down the safety of DWR
- Fluorocarbon concerns: Many brands now use shorter-chain fluorochemicals or fluorine-free alternatives to reduce toxicity and environmental harm.
- Direct exposure: While exposure from wearing treated fabrics is minimal, applying sprays or washes without proper ventilation might pose risks.
- Environmental focus: Companies are increasingly shifting to sustainable options, but users should check product labels for safety certifications like bluesign®8 or OEKO-TEX®9
DWR is safer than ever, but consumers should remain informed and prioritize brands committed to eco-friendly solutions.
4. Does DWR wash off?
Yes, DWR coatings degrade over time due to washing, abrasion, and environmental exposure. Washing with strong detergents or improper cleaning can significantly reduce its effectiveness.
DWR coatings do wash off eventually, especially without proper maintenance, but reproofing can restore water repellency.
Caring for DWR-treated fabrics
- Avoid harsh detergents: Use specific cleaners designed for outdoor gear. Harsh detergents can strip the coating.
- Follow care instructions: Check the garment tag for washing and drying guidelines.
- Reproof regularly: When water stops beading, use a reproofing product to restore the coating.
Neglecting these steps can leave your gear vulnerable to moisture. By washing carefully and reapplying treatments, you can maintain its performance over the long term.
5. Conclusion
DWR fabric is crucial for outdoor gear, providing water resistance that boosts comfort during activities. Over time, its effectiveness fades, so proper care is needed to maintain it. Many brands now use eco-friendly DWR treatments, which are safer for people. Though the coating wears off, regular reproofing can keep your gear performing well. Knowing this helps you choose and care for DWR products wisely.
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A fluoropolymer is a fluorocarbon-based polymer with multiple carbon–fluorine bonds. It is characterized by a high resistance to solvents, acids, and bases. The best known fluoropolymer is polytetrafluoroethylene under the brand name "Teflon". ↩
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PFOA(Perfluorooctanoic Acid) and PFOS(Perfluorooctane Sulfonate) are synthetic chemicals in the perfluoroalkyl and polyfluoroalkyl substances (PFAS) group, and are very stable and don’t interact much with other chemicals, known for their resistance to heat, water, and oil. ↩
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Paraffin wax (or petroleum wax) is a soft colorless solid derived from petroleum, coal, or oil shale. It is solid at room temperature and begins to melt above approximately 37 °C (99 °F), and its boiling point is above 370 °C (698 °F). Common applications for paraffin wax include lubrication, electrical insulation, and candles; dyed paraffin wax can be made into crayons. ↩
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A perfluorinated compound (PFC) or perfluoro compound is an organofluorine compound that lacks C-H bonds. One class of perfluorinated compounds, the fluorosurfactants, are widely used in the production of teflon (PTFE) and related fluorinated polymers. They also have been used to confer hydrophobicity and stain-resistance to fabrics. ↩
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"PFC-free" means a product is made without perfluorinated chemicals (PFCs), a group of substances that can harm the environment and human health. PFC-free products are safer and more eco-friendly alternatives. ↩
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"Reapply DWR sprays" means using a durable water repellent spray to restore the water-resistant coating on outdoor gear or clothing after it wears off over time or with use. ↩
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"Wash-in treatments" are products applied during laundry to add specific properties, like water repellency or stain resistance, to fabrics. They are absorbed into the material during the washing process. ↩
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Guide you to the official site of bluesign®. ↩
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Guide you to the official site of OEKO-TEX®. ↩
