Back to Contents May 20, 2014

Textiles' Silver Lining


By Glenna B. Musante


Few things are as unpleasant as smelly socks or gym clothes, but antimicrobials mixed with high performance fibers are providing some relief.

As Mike Smith of Chemtex Lab says, performance wear (in other words, those gym socks, running shoes, and workout clothes), needs extra help fighting off the bacteria that can cause odor. Says Smith, the extra sweating and perspiration on these products can be trapped in the fibers. This is especially demanding on any fabric, he says, and some garments will maintain that sour odor even after a good washing. This is especially true of sportswear worn over and over, especially if not washed right away. When left unwashed, odor-causing bacteria can proliferate, plus contaminate one’s gym bag, making it full of odor-causing bacteria as well.

Managing that with, say, a tee shirt is fairly easy, but products that can’t be thrown in the washing machine, pose a more difficult bacteria/odor management issue. One solution is adding a silver-based antimicrobial into the fiber mix. Here, AATCC News offers this update on the use of these silver-based antimicrobials to provide combat a smelly problem.

Every Fiber Has a Silver Lining

Silver is increasingly emerging as a popular antimicrobial ingredient, especially with the development of recycled silver salt and nano silver applications, which can reduce the cost of this potentially expensive ingredient.

Silver is a natural antimicrobial that is considered allergenic and in labs, has an impressive microbial kill rate, as high as 99 percent, depending on the application. Carolina Silver is one of many firms emerging that offer textiles treated with silver-based antimicrobials for applications in performance apparel as well as bedding, hosiery , and other products. Company literature says that their manufacturing process permanently bonds silver to the surface of a fiber, evenly distributing the silver ions, for a permanent layer that can last up to 50 washes.

Silver Socks, Plus

Swiftwick, which makes performance socks, uses micro-silver particles to reduce microbe growth. Their process involves bonding the silver to the fibers. “It’s less expensive to create materials and products with silver embedded in the textile,” says to Mark Cleveland, CEO of Swiftwick, “but it’s less efficient in terms of performance.” His company uses a bonding process to adhere medical grade silver particles to targeted materials. “In our health-critical applications,” he adds, “we want the silver to be maximally deployed. We’re not concerned with the cost, only the efficiency.”

They also use copper, which has similar antimicrobial properties, and building on that, have been moving to the use of trilobal nylons—which, they say, provide moisture wicking plus capture dye in a way he describes as “eye popping.”

Fancy Feet

Dow Microbial Control has introduced another silver-based antimicrobial designed to control undesirable bacteria. Their Dow Silvadur Antimicrobial is a silver ion solution applied to the surface of performance footwear, which is activated by the presence of odor-causing bacteria. Silvadur is currently being used in trials with US and European footwear manufacturers and Xtep International Holdings, a leading, China-based manufacturer of performance footwear and apparel, is using Silvadur in its athletic shoe brands. The general approach with these manufacturers has been to treat the lining of insoles, rather than the surface, with the technology.

And the numbers are in:

Dow released a survey that said consumers will pay more for performance wear treated with antimicrobials. In their study, they say that consumers reported being willing to pay from five to 20 percent more for apparel and also home furnishings that have “new generation” antimicrobial properties. So treating performance fabrics with antimicrobials really pays off.


Check out the discussion about antimicrobials on AATCC’s LinkedIn Group

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