Preparation of multifunctional coating materials and their applications
Espoo : VTT Technical Research Centre of Finland,
|Publish Date:|| 2005-05-20
|Thesis type:||Doctoral Dissertation
|Defence Note:||Academic Dissertation to be presented with the assent of Faculty of Science, University of Oulu, for public discussion in the Auditorium L10, Linnanmaa, on September 5th, 2003, at 12 o'clock noon.
Sol-gel technique has been utilized for the fabrication of multifunctional inorganic-organic hybrid materials for specific applications. Synthesized methacrylic acid and benzoylacetone modified tin alkoxide precursors were used for the first time for the realization of directly UV-photopatternable antimony-doped tin dioxide coatings. These single-layered coatings have transmission values over 80 % at visible wavelengths and maximum electrical conductivity values around 15 S/cm. In comparison, multi-layered coatings without UV-photopatternability properties were fabricated. In this case, electrical conductivities are in the range of 10² S/cm. A novel material technique approach for laser protective eyewear was utilized for the synthesis and preparation of the mechanically tolerant and near-infrared absorbing filter coatings. Optical densities from 2 to 4 at laser threat wavelength, a ten fold increase in scratch resistance, and a hundred-fold increase in abrasion resistance, compared to uncoated polycarbonate substrates, were obtained by using absorbing dye-molecule doped sol-gel materials. Fabrication of a diffractive optical element, namely axicon, using hybrid-glass materials was demonstrated for the first time. Hybrid-glass material was tailored to fulfill the requirements of the functional axicon element.