Dual functionality anti-reflection and biocidal coatings
A thin film combination of anti-reflection and biocidal properties would be of particular interest to reduce the transfer of infection and improve readability of touch screens. In a study, the development of a dual functionality film of silica and copper oxide was described.
Deposition was via flame assisted chemical vapour deposition which has the advantages of being a cost efficient atmospheric pressure technique enabling use of non-volatile precursors and that no closed reaction cell is required so making it ideal for integration into industrial production lines.
Three layers are better than two
The resulting films were characterised by a range of techniques including optical spectroscopy, electron microscope and X-ray fluorescence. Biocidal behaviour was tested by determining the kill rate of Escherichia coli. A 3 layer stack on glass of silica/copper oxide/silica had better adhesion and lower reflection than a comparable 2 layer stack. This multilayer film led to a > 2% drop in reflection from that of uncoated glass, similar to that of silica only film. In addition, showed a > 6 log10 kill between 6 and 24 h for as deposited and annealed samples.
The study is published in:Surface and Coatings Technology, Volume 324, 15 September 2017, Pages 201-207
