Bio-functional garments like stockings with aloe vera, T-shirts with vitamin C and underwear that smells like vanilla have been developed as the textile industry takes its cue from the food industry. This serves to give the garments an additional function in addition to keeping the body warm.
Whether the clothes keep their promises is a contentious matter. Experts also fear the garments could lead to allergic reactions. Various techniques are applied in the production of bio-functional textiles. One method involves simply putting the substance on the surface of the material, said Hans-Juergen Buschmann, a chemist at the German Textile Research Center in Krefeld.
Aloe vera, a plant-based product found in many lotions or jojoba, used in cosmetics as a moisturizer, is applied to textiles in this way. The catch is the substances eventually are washed out of the clothes. Clothing that has the active ingredient in its fiber is better able to maintain its function despite multiple washings.
A Japanese producer has developed a fiber with a substance that transforms into vitamin C when it comes in contact with the skin. In another process, algae are combined with clothing fibers, and when the clothing is worn, minerals, proteins and vitamins are released. It has also been proved that the human skin is capable of absorbing the substances, according to Uta-Christina Hipler, Director of the laboratory at the Clinic For Dermatology at the University in Jena. The laboratory conducted dermatological tests on the fibers.
Garments with microcapsules that contain certain skin-pampering agents like vitamin E or scents such as lavender or orange oil are sold widely. The capsules are made from a variety of materials that open and release their contents when rubbed, pressed or warmed by body heat. Wearing the garment and washing it reduces the number of microcapsules, and the item loses is extra functions.
To counter this, manufacturers recently began offering consumers packets to refresh the supply of microcapsules, Buschmann said. These packets can be emptied onto the garment after it's washed. Buschmann said he was skeptical about this actually being affective. Clothing with cyclodextrines (produced from starch) is different, and they fulfill two functions. They can not only release scents and personal care products but also store unpleasant odors such as sweat or cigarette smoke, leaving sport coats still wearable after a night out at the bar.
Cyclodextrines, which can be anchored in the weave of the fabric, contain molecular-sized hollow compartments in which either a desired or undesired scent can be stored.
The body's moisture releases the active ingredient. The same thing happens in the washing machine, but the cyclodextrines are not destroyed in the process and can be refilled after every wash by spraying the garment with a favorite perfume. If the scent isn't wanted after a period of time, the only thing that needs to be done is moistening the garment.