The durability and anti-soiling properties of sol-gel-based easy-to-clean and finger-print-resistant coatings for steel surfaces

Modern coating techniques based on nanotechnology enable development and tailoring of new coating systems which provide improved anti-soiling properties to different materials. Currently, sol-gel technique has been commercially applied in products with anti-soiling properties. However, little of the durability properties and service life is known of these products. The overall objective of this study is to create concepts to functionalize surface structures of steel material in relation to easy-to-clean properties as well as to verify the applicability of the material in the target conditions. Stainless steel surfaces were thin-coated by applying sol-gel technique with commercial, semi-commercial and newly developed coatings. The chemical composition of the coatings differed in relation to the quality and quantity of ceramic nanoparticles. The surface energy, hydrophobic and oleophobic properties of the coatings were determined by contact angle measurements. The durability properties of the coated materials were evaluated by applying the accelerated abrasion test by means of Ericsen apparatus. The anti-soiling properties of coated surfaces were detected by FTIR technique. The improved anti-soiling property of the coatings was due to the increased oleophobicity and hydrophobicity. The durability of the sol-gel coatings was shown to be highly dependent on the increased number of ceramic components. Best results with tailored coatings were obtained with suitable polymeric and ceramic mixture.