Down – a superhero of insulation materials! Synthetic fibres can’t compete. But like every superhero, down also has a nemesis. And in down’s case, this is moisture. Moisture is down’s kryptonite. It is precisely for this reason that impregnated down has been on a seemingly unstoppable advance in the outdoor sector for several years.
But how does it actually work? Can it even work? Let’s take a closer look!
Why moisture damages down
To understand what the advantages of an insulated down are, we must first look at how exactly the warm plumage insulates. And why moisture destroys this insulation. According to the omniscient Internet encyclopaedia, the word down comes from Icelandic and describes the lower plumage of waterfowl. With its many small and fine branches, it can trap particularly large amounts of air. As a result, the body’s own heat can be stored very well, which is synonymous with high insulation performance.
Once moisture comes into play, the down sticks together. This means that the branches can no longer store air. The fill power, also called loft, is also lost. The down-lined textile therefore no longer keeps properly warm under the influence of moisture. But wait a minute! Isn’t down the lower plumage of waterfowl? Don’t they have to deal with water in their natural habitat all day long? That’s right. That’s why these clever little animals grease their down feathers with an oily secretion from the root gland. Although this might sound a bit disgusting, it serves the simple purpose of protecting the fine feathers from water. Impregnated down does the same.
How does impregnated down work?
The down used in outdoor textiles basically takes its moisture protection from nature. An externally applied DWR treatment agent should protect against moisture. Although the agents used in industry do not originate from ducks and geese, many well-known outdoor manufacturers take care to not use too many chemicals in production. Many DWR treatment agents used in the textile industry are criticised for their harmful ingredients. And rightly so. That is why many manufacturers of well-known outdoor brands make sure to work with PFC-free DWR treatment agents. PFCs are fluoro-organic carbon compounds. Although these are very efficient in their water-repellent properties, they are also considered harmful to the environment and even the human body. Manufacturers provide information on PFC-free and solvent-free down and fabric DWR treatment on their website or in the respective item description.
Before water-repellent down can be used in down vests, sleeping bags or down jackets, where it ensures comfortably warm outdoor experiences, it must first be impregnated. This is carried out through a special wash. The dry treatment covers the insulation plumage like a protective film. The result is long-lasting protection against moisture that can even survive up to five washes in your washing machine. By the way, impregnated down insulation is no heavier than untreated insulation. This means that the total weight does not change.
What does this mean in practice? Does this moisture protection work in outdoor use and under extreme conditions? Various laboratory tests have shown that water-repellent treated down is much less susceptible to moisture than “normal”, untreated down. But as with many things in life, tests under laboratory conditions are not always an indicator of how things really are in natural conditions. The girls and boys from Freizeitalpin have reported in their article on the performance of treated down on a practical test. It was tested by someone who really knows their stuff. The Nikwax environmental officer dared to make a lake crossing of a special kind. Lying on his back in an impregnated sleeping bag, he crossed a lake in southern England. And lo and behold: he (and the sleeping bag) survived the rather different boat trip undamaged and almost dry!
How do I impregnate down jackets etc.?
Jackets, sleeping bags and people all meet the same fate at some point. They begin to smell and need a wash. Textiles insulated with impregnated down lose their water-repellent properties after four to five washes. The down can also absorb water with general soiling. If you notice that your textile does not insulate as well in damp weather or when you start sweating, this is a sign that you need to do something. Special down detergents are available for cleaning. These ensure that the jacket is clean again. The first step is to wash the jacket according to the instructions.
For re-impregnation, instead of washing the jacket with a down detergent, put it in the washing machine with a “Wash-In dry treatment” which is specially developed for down products. Instead of detergent, add the specified amount of DWR treatment to the detergent compartment. Select a gentle cycle and a low temperature. 30°C is perfectly adequate. Use as low a spin as possible. Although it is important to spin a lot of water out of the textile, wet down is heavy so a high speed can damage the down chambers. It is therefore better to spin at a low speed and repeat several times. The dry treatment is then ready! Well, almost. Now the jacket just needs to be put in the tumble dryer. But again, not too hot! And, as usual, with tennis balls to prevent the down from clumping. It’s best to do two drying cycles and then shake out well.
Important for both cleaning and re-impregnation: read the care instructions provided by the manufacturer for your textile and the instructions for the care product carefully.
If you have any further questions, our customer service team would be happy to help. Hannes is our expert for all things down clothing. You can contact him on weekdays from 9:00 to 18:00 by telephone +49 (0)7121/70 12 0 or by email.