As part of an AiF research project, scientists from the Hohenstein Institute in Boennigheim are said to have for the first time developed a textile finish with both an antiviral and an antibacterial function. The  technology has been developed to be used for products in nurseries, child day care centres and hospitals to interrupt chains of infection.

Respiratory problems

Most infection-induced respiratory problems are caused by viruses, the researchers say. For example, the respiratory syncytial virus, a pathogen belonging to the family of paramyxoviruses, can cause infections of the upper respiratory tract in the form of colds, coughs, acute bronchitis or even pneumonia, particularly in small children.

To avoid droplet and smear infections as far as possible, hygienic hands, textiles and surfaces are of paramount importance, the Institute reports.

Risk of infection

Textiles can play a part in spreading pathogens. Viruses do not have their own metabolism and can therefore only survive for a limited time outside a host, and unlike bacteria, do not multiply there.

However, studies have shown that textiles that are in regular contact with hands can contribute to the spread of viruses. The test design included cleaning cloths in which, for the first time, antiviral and antibacterial effectiveness were combined with each other in one functional textile finishing.

“Over the long term, we are interested in finding out whether the risk of infection, that is to say the spread of germs from person to person, can be reduced by using biofunctional textiles in the future,” explained Prof Höfer, Head of the Hygiene, Environment and Medicine Department.

Antiviral finish

Various organic and inorganic colloidal or nanoparticle copper compounds and copper complexes were first applied in a sol-gel process. The effectiveness of the textile microfibre substrate was optimised using various application techniques such as foulard or spray methods.

A second alternative antiviral finish of microfibre cloths was achieved by finishing with copper pigments in a high-temperature exhaust process. In a similar way to dyeing with dispersion dyes, the dispersed copper pigments were incorporated in the fibres in a slightly acid environment. In a second step, fixing was carried out using a polymer binding agent in a cold padding process to protect the copper particles against mechanical abrasion.

Reducing virus concentration

The effectiveness tests were carried out on different surfaces, such as glass, stainless steel or wood, which were contaminated with viruses and wiped with the finished cleaning cloths. The bacterial virus MS2, a non-pathogenic surrogate virus, which is comparable to clinically relevant viruses such as novovirus, poliovirus, hepatitis A or enteroviruses, was used as the test virus.

The finished microfibre cloths absorbed 91% of the applied viruses, the Institute reports. At the same time, the virus concentration in the cloth was reduced by approximately 90 %.

In future, this new functionalisation could be of interest in the domestic environment, in hospitals, old people's homes, care homes and in communal facilities (e.g. canteens) and in protective clothing for the fire brigade, emergency services and military.

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