Reports and Surveys PROTECCIÓN LABORAL 70 | 1erTrimestre12 Hohenstein Institute Don’t give micro-organisms a chance: Development of workwear that is antimicrobial, comfortable and suitable for leasing In many areas, but especially in food- processing companies and catering faci- lities, hospitals and care homes, hygie- nic workwear is extremely important. As part of a research project (IGF No. 16039 BG), scientists at the Hohenstein Institute, in cooperation with the Thürin- gen Institute for Textile and Plastics Research and the Saxony Textile Research Institute at the Technical University of Chemnitz, have developed a fabric for making antimicrobial workwear suitable for leasing that is based on regenerated cellulose fibres, and they have examined it with regard to its properties when it is used and cleaned. The aim of the research project was to com- bine properties such as, on the one hand, a protective function, high mechanical strength, a long service life and ease of care with, on the other, good physiological func- tionality and a high level of comfort, in one garment. This would result in workwear made from regenerated cellulose fibres that is pure white, antimicrobial, suitable for leasing and comfortable as well. Textiles are an important transmission route for micro-organisms and so there is a high risk of microbial contamination from unhygienic workwear. Along with the requirement for the workwear to meet high hygiene standards, it is also very important for it to be comfortable to wear , as this affects the well-being of the wearer. Many users still prefer cotton because it is so comfortable to wear. Regenerated cellulose fibres show some of the same characteristics as cotton, but, because they are synthetic in origin, they can be given an antimicrobial treatment. This characteristic was used in the manu- facture of the new material. Very often, the effectiveness of the antimi- crobial workwear that is available on the market is based on silver which is incorpo- rated into the fibres. Silver has been known to have bactericidal qualities for about 3000 years. One of the disadvan- tages of it is that, depending on the form in which the silver is applied on or in the fibres, it can cause darkening or colour changes when the fabric is washed, or as a result of other external influences. Howev- er, because of the association with cleanli- ness, in hygienically sensitive areas pure white workwear is preferred. Three versions of the fibre: zinc, zinc oxide and silver nitrate In developing the new materials, three ver- sions of the fibre were first produced, to which zinc, zinc oxide and silver nitrate were added. Using zinc to produce an antimicro- bial effect in textiles is an innovative approach, because zinc has hitherto barely been used at all in textiles. Zinc proved to have the same advantages as silver when used as an active ingredient, and is a safe, well-researched substance which, unlike sil- ver, does not cause any change of colour dur- ing processing and care treatments. The results show that the new, carefully dosed fibre variants, subject to certain specif- ic requirements, can be used to make work- wear containing a high proportion of cellu- lose fibres, something which is often request- ed by wearers. The version with silver nitrate also had titanium oxide added, so as to avoid subsequent discolouring of the thread even at the manufacturing stage. However, adding titanium oxide to the fibres contain- ing silver nitrate did not result in any improvement. The changes in colour which occurred were lighter, but still visible. The quality of the new fibres was tested in practical use. Compliance with the mini- mum technical standards for textiles, such as garment manufacturing requirements, comfort and suitability for leasing, was tested using the terms of DIN 10524, and the antimicrobial effectiveness was tested after 100 washing and drying cycles. The positive results of these tests show that the research project can form the basis for a new, innovative approach to making antimicrobial textiles using zinc and regenerated cellulose fibres. These newly developed fibres and the woven and knit- ted fabrics made from them provide effec- tive hygienic protection, are comfortable to wear and very suitable for leasing, and so will help improve hygiene and reduce the transmission of infectious diseases, especially through food. This should con- siderably reduce infection rates in the gen- eral population, leading to financial sav- ings in the healthcare system and so, ultimately, to benefits for members of health insurance schemes. The results are being made available for general use by all interested parties such as the textile industry, the chemical indus- try and the clothing industry.  Copyright Hohenstein Institute, Boennigheim, Germany. All rights reserved.