Development of workwear that is antimicrobial & suitable for leasing
In many areas, but especially in food-processing companies and catering facilities, hospitals and care homes, hygienic workwear is extremely important.
As part of a research project (IGF No. 16039 BG), scientists at the Hohenstein Institute, in cooperation with the Thüringen 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 combine 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 functionality 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 manufacture of the new material.
Very often, the effectiveness of the antimicrobial workwear that is available on the market is based on silver which is incorporated into the fibres. Silver has been known to have bactericidal qualities for about 3000 years.
One of the disadvantages 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. However, because of the association with cleanliness, in hygienically sensitive areas pure white workwear is preferred.
In developing the new materials, three versions of the fibre were first produced, to which zinc, zinc oxide and silver nitrate were added. Using zinc to produce an antimicrobial 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 silver, does not cause any change of colour during processing and care treatments.
The results show that the new, carefully dosed fibre variants, subject to certain specific requirements, can be used to make workwear containing a high proportion of cellulose fibres, something which is often requested 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 containing silver nitrate did not result in any improvement. The changes in colour which occurred were lighter, but still visible.