This self-cleaning effect is achieved, for example, through the use of photocatalytically active materials or surface coatings. When light of the appropriate wavelength falls on the photocatalytically active surface, organic contaminants are decomposed. There is also an additional secondary effect: The light causes a so-called “hydrophilization” of the surface, making it “water-loving”, for example water forms a film that can infiltrate the dirt particles, enabling them to be rinsed off more easily. In order to be able to compare the photocatalytic activity of different products, the German industrial standard DIN 52980:2008 is applied, whereby the verification is carried out via the degradation of methylene blue. In the past, strong fluctuations of the measurement results occurred repeatedly in practice, and a number of weak points in the current method have also been pinpointed in the scientific literature.
“For the Fraunhofer Institute for Surface Engineering and Thin Films IST, this was an incentive to work in collaboration with partners from industry and research in order to develop a robust and application-oriented German industrial standard for characterizing the photocatalytic activity of surfaces,“ explains Frank Neumann, Head of the Working Group Photo- and Electrochemical Environmental Engineering. “The cooperation project was also an excellent opportunity for MRC to take up exciting approaches from research in order to introduce them into standardization work together with our long-standing partners and to transfer them into new product ideas,” confirms Dr. Marcus Götz, Managing Director of MRC Systems GmbH in Heidelberg.