70Reports and Surveys effects because of their tiny size, which makes them highly bre- athable? Can they be absorbed, even through the dermis? Silver biocide and the intramural nano-weaving As a textile authority, Spain has not been left out of research in the field of silver for the development of more aseptic cos- tume. A few years ago, Aitex and Aitpa developed a joint pro- ject whose results and conclusions “offer a star ting point for the textile company that is considering opening its portfolio of products to the market for antimicrobial and antifungal texti- les” stated Aitex. The report of the AITEX Group Research in Functional and In- telligent Textiles pointed out several conclusions, which can be summarized as follows: -The antibacterial and antifungal textiles represent a potential market with high expectations in the short to medium term from the increased awareness by the consumer, and the results of investigations which show the properties of some of these bio-active agents. Los tejidos se impregnan de sudor, cuya descomposición es responsable del mal olor. (Foto gentileza de Polygiene) e fabrics absorb sweat, whose decomposition provokes bad odors (Photo courtesy of Polygiene) -The results show that not all the threads existing in the mar- ket and used for this purpose have bioactive properties.There- fore it is essential defining first the level of requirements to be met by the product, being also essential to relate this variable with the application that one wants to give the textile article. Thus, a textile product that, for example, should be used as hospital menage will have to be effective against a range of bacteria and fungi determined in comparison, for example, with a sock that should initially be effective only against fungi res- ponsible for athlete's foot. -From a scientific standpoint, it appears that silver is the quin- tessential bio-active agent and that best antibacterial and anti- fungal properties present, regardless of its oxidation state. While ionic silver has a better performance due to its higher reactivity, and therefore, enhanced cellular penetration and ef- fectiveness. Still, the silver metal allows using this type of wire for other applications such as anti-static uses. Moreover, alter- natives are emerging, with good results, mainly based on cop- per bio-active agent. -It has been found a significant difference in effectiveness bet- ween threads that have the bio-active agent in its own surface (regardless if it is metal or ion) with respect to other threads with the core made of continuous filament from the bio-active metal, and coated by conventional wires. In the latter case, the effectiveness is significantly reduced because the bioactive agent is inside (it is masked), proving more difficult to action against germs.This type of construction leads toward textile conductive wires that dissipate static charges. -The skin compatibility of silver fabric is suitable for use in ap- plications that present a direct and prolonged contact with skin. And for the wire considered is independent of chemical state of the silver, ionic or metallic. Ag Biocides, some examples Some products on the market attempt to resolve some reaso- nable doubts that we have wanted to reflect in this article. Among the newest Ag biocide products (Ag is the symbol of silver, Argentum, in Latin), we draw the attention to: Silver genuine antibacterial and antifungal agent In fact, little is known about the mechanisms of an- tibacterial silver compounds.The germicidal action is attributed to structural and morphological chan- ges observed in the bacteria after being treated with silver compounds. Images of electron micros- copy show damage to the cell membrane and ele- ments of cytoplasm. Silver also interferes with the function of DNA and RNA of microorganisms. Since the bacteria’ membrane is responsible for controlling breathing and exchange of materials with the environment, destroying the membrane avoids the processes of respiration, so bacteria die. But the use of silver transcends the area of clo- thing.The growing ineffectiveness of current anti- biotics for infectious diseases has led to develop products using silver as microbiocide agent. In some places it is a common activity to produce and sell colloidal silver for use in water purification and washing fruits and vegetables.With the deve- lopment of nanotechnology it has been possible to make nano-materials and new products such as washing machines and dishwashers, based on the use of the nano-particles as cleaning agents. er JOBWEAR 610 12o TRIMESTRE 2012