Antimicrobial finish

Substances added to fibres, snch as lubricants, antistats, natural-based auxiliaries (for example size, thickener and hand modifiers) and dirt provide a food source for microorganisms. Synthetic fibres are not totally immune to microorganisms, for example polynrethane fibres and coatings can be damaged. Of course, because of evolution, natnral fibres are more easily attacked. Wool is more likely to suffer bacterial attack than cotton, and cotton is more likely than wool to be attacked by fungi. 

The use of antimicrobial finishes to prevent unpleasant odours on intimate apparel, underwear, socks and athletic wear is an important market need. The odours are produced by the bacterial decomposition of sweat and other body fluids, and controlling bacterial growth by hygiene finishes reduces or eliminates the problem. An alternative approach is described in Chapter 18 on novel anti-odour finishes. 

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Textile Finishing. Polyethyleneimine-A/-methylolurea derivatives improve the crease and wear resistance of cotton (429,430). The adhesion between individual wool fibers is improved by pretreatment with amines, which leads to improved shrink resistance (431). An antimicrobial finish can be appHed to cotton by using a combination of PEI and ureas to bind zinc pyrithione to the fabric (432). After wool has been provided with a flameproof finish using fluorozirconate or fluorotitanate, the wool can be neutralized with PEI (433). Conventional neutralizing agents caimot be used for this purpose since they impair the flameproof characteristics of the impregnated fabric. 

Almost no effect Soil-release finishes Antistatics, if not softening and smoothing Finishes to improve colour fastness Finishes for protection from UV or insects Antimicrobial finishes... 

The growth rate of microbes can be astoundingly rapid. The bacteria population, for example, will double every 20 to 30 min under ideal conditions (36-40 °C or 77-98 °F, pH 5-9). At this rate, one single bacteria cell can increase to 1 048 576 cells in just 7 hours. Therefore, antimicrobial finishes must be quick acting to be effective. 

The second type of antimicrobial finish consists of molecules that are chemically... 

A widely used biocide and preservation product is formaldehyde. Solutions of formaldehyde in water, called formalin, were used for disinfection and conservation, for example, of biological samples for display. Bound formaldehyde is released in small amounts from common easy-care and durable press finishes (Chapter 5). Therefore these finishes include - at least until they are washed - a small antimicrobial side effect. This can also be true for some quaternary compounds, for example wet fastness improvers and softeners. But for more effective requirements specific antimicrobial finishes are necessary. 

Research into controlled-release antimicrobials continues with organo-silver compounds and silver zeolites, which are promising candidates for textile finishes. Silver ions, for example, incorporated in glass ceramic, have a very low toxicity profile and excellent heat stability. These principles are also used for fibre modification, an alternative to the antimicrobial finishes with high permanence. In recent years a variety of antimicrobial modified fibres have been developed, including polyester, nylon, polypropylene and acrylic types. An example of these fibre modifications is the incorporation of 0.5-2 % of organic nitro compounds... 

A general problem of antimicrobial finishes is their selective effect. Some are... 

Rajan J, Antimicrobial Finishes for Textiles, presented at the Chemical Principles of Textile Finishing Short Course, North Carolina State University, Raleigh, NC, March 1999. 

Prevention Antimicrobial finishes or fibre modifications hinder the decomposition of sweat Permanent with respect to washing and dry cleaning, especially in the case of fibre modification, restricted to smells from sweat decomposition, therefore only for clothing with skin contact. 

One way to prevent the development of unpleasant odours that originate from the decomposition of sweat are antimicrobial finishes or bacteriostatic modified fibres. They prevent the decomposition of perspiration by bacteria to bad smelling products as described in Chapter 15. 

Journal of Applied Polymer Science 94, No.l, 5thOct.2004, p.243-7 ANTIMICROBIAL FINISHING OF ACRILAN FABRICS WITH CETYLPYRIDINIUM CHLORIDE Zaisheng Cai Gang Sun... 

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