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Common misunderstanding about DWR (durable water repellency)

Written by Takanori | Aug 6, 2024 8:00:23 AM

DWR on outdoor jackets is an abbreviation for Durable Water Repellency, but its explanation is often misunderstood. Here we will explain the correct knowledge of DWR and hope it will lead you to a more comfortable outdoor life.

 

GORE-TEX waterproofness decreases

This is a misunderstanding. It is not the waterproofness that decreases, but the water repellency. The difference between waterproofness and water repellency is that water is kept from passing through the fabric and the fabric does not absorb water, but the actual physical phenomenon is completely different. Therefore, water repellency differs from waterproofness because the fabric does not absorb water but allows it to pass through.

The waterproofing performance of GORE-TEX is due to the presence of a physical membrane, which will not deteriorate if there is no physical damage such as a tear.

Water repellency, on the other hand, is a scientific action of the fabric's surface that repels water, so it will deteriorate with wear and tear and other stresses during use. Regular maintenance and care is required to restore water repellency.

 

DWR affects moisture permeability.

Correct, but it is not only the breathability that is affected. It is that the fabric absorbs water, which makes you feel colder, and the jacket accumulates water, which makes it heavier.

This has to do with the structure of waterproof breathable fabrics such as GORE-TEX, which consists of a membrane that is sandwiched between nylon and other fabrics to protect the main body of the fabric. These are sandwiched and laminated together to form a waterproof breathable fabric such as GORE-TEX.

Since the outer and inner fabrics are no different from ordinary fabrics, the loss of water repellency in those fabrics not only inhibits breathability, but also causes the jacket to absorb water, which increases its weight and lowers its body temperature.

 

DWR in rain jackets is removed or weakened when washed.

It is not wrong, but with correct washing, the decrease in DWR is small.

It would be wrong to say that washing does not reduce DWR at all. However, water repellents are selected based on the impact of 50 or 100 washes. It is true that the DWR does not decrease at all with washing, but it is treated in such a way that the DWR is not lost even after 50 or 100 washes.

On the other hand, if the garment is not washed properly, the DWR will decrease significantly. If the detergent is chosen incorrectly, if more detergent is used than expected, or if the rinsing is not sufficient, the DWR will decrease quickly.

 

DWR decreases over time.

DWR does not decrease over time; it decreases due to the stress of use DWR does not decrease at all if it is not used. Rain jackets are subjected to stresses from use, such as abrasion, dirt buildup, and rain acclimation.

These stresses can cause the threads themselves to break or fall out, or only the DWR coating can peel off. This will degrade the DWR performance.

 

Heat will restore DWR.

In some cases, this is correct, but it is more accurate to say that DWR can be restored by applying heat.

There are three main factors that can cause a decrease in DWR: dirt adhesion, DWR shedding, and when the DWR becomes acclimated to water. Only if the DWR of one of these factors becomes acclimated to water, it may be recovered by the application of heat.

Therefore, it may not recover even with the application of heat. In that case, another method should be tried. In the case of stain adhesion, laundering should be performed. if the DWR has fallen off, DWR treatment is needed again. please refer to the following topics for DWR reprocessing.

 

It is better to put on a lot of DWR treatment agent.

This is not true. Too much treatment agent can cause staining.

It is understandable to think that the more DWR treatment agent you apply, the longer the effect will last.

Unfortunately, this does not mean that the effect will increase. In fact, applying too much may reduce the performance. It may also leave a stain. Since defects are more common, DWR Treating Agents should be used in the prescribed amount.

 

Commercial DWR treatments and product DWR treatments are the same

This is a mistake. There is a difference between the DWR treatment available to the general public and the DWR treatment applied to GORE-TEX products.

The DWR treatment applied to the product is machine-treated to fix to the fabric, while the commercial DWR treatment cannot be machine-treated, so it is designed to be treated at home. The advantage is that the treatment is easy and simple, especially without the need for a machine. On the other hand, it is a disadvantage that the DWR performance cannot be as good as the DWR applied to the product.

If you are not satisfied with the commercial DWR treatment, please consult with us, professional DWR suppliers.