Within "FlexPol", an EU project, an international project consortium led by Fraunhofer IPT developed a manufacturing approach to apply antimicrobial surface structures extensively and cost-efficiently in adhesive films. Combining material and surface structure, a wide range of germs can be killed at 99.99% efficiency and their growth can be slowed down.
Germs in hospitals can lead to life-threatening infections, not least in particularly vulnerable patients. Strong disinfectants and cleaning agents are used to clean surfaces off bacteria. The »FlexPol« research project, however, capitalized on a combination of materials and surface structures which directly inhibit and prevent the spread of germs. This way, patient health is protected as well as that of medical personnel, as strict hygiene standards require in medical environments. This is also of economic benefit: Expenses for cleaning detergents and disinfectants can be greatly reduced.
The project started with formulating the material. A polypropylene basis is interspersed with nano-capsules and extruded to form a thin film. These nano-capsules contain essential oils with antimicrobial properties. Hot stamping added nanostructures to the film which inhibit adhesion of bacteria and fungal spores. The structures were chosen to damage the membranes of the microbes mechanically and kill the pathogens. The Fraunhofer IPT combined the film material, stamping tools and instruments to monitor product quality in one single pilot line. The challenge of this production process was to apply the antimicrobial surface structures smoothly and extensively onto the film material. Another challenge was to transform the production process of the innovative films into an industry-oriented process. We aimed to prove the transfer of materials, structures and processes which so far has only been tested in the lab.
The Donostia University Hospital in Spain and the laboratories of Minho University in Portugal examined and assessed suitability and efficiency of the films. The idea was to cover entire walls and floors in hospitals in the film and to minimize microbial contamination across a wide space. Later, industries other than the medical industry, too, would be able to benefit from this antimicrobial film, for instance the food industry or manufacturers of public transport and public restrooms.