The proposed innovation is an antifog coating for polycarbonate substrates applied using a unique deposition technology. The deposition technology, Aerosol Impact Driven Assembly (AIDA), is a dry spray coating process capable of producing thin films with tunable porosity and surface roughness. By using AIDA to optimize the porosity and surface roughness of SiO2 films, a super-hydrophilic, mechanically durable and chemically stable anti-fog coating for polycarbonate can be produced. The durability of the film combined with the ability to uniformly coat large area, irregularly shaped, objects makes it an idea candidate to replace the anti-fog coating currently used on the EMU helmet. Initial tests suggest that the anti-fog coating has the potential to outlast the useful life of the EMU helmet. The investigators have previously used AIDA to deposit durable anti-fog coatings onto glass substrates. While initial results on polycarbonate substrates are positive, there remains much opportunity to optimize the coating design and thus performance for polycarbonate. The main objectives of the work can be broken down into four tasks: Use optical simulation software to help design coatings with ideal optical properties for polycarbonate. Produce the simulated coatings using AIDA and evaluate the coatingsĀ optical and anti-fog performance. Further iterate on the design if necessary. Subject coatings that meet optical and anti-fog specifications to durability tests meant to simulate use in an EMU helmet. Iterate on the design if necessary to meet durability requirements. Demonstrate that a coating that meets optical, anti-fog, and durability specifications can be reproduced on large areas. The deliverable of this project will be >20 samples of polycarbonate sheets coated with the best performing coating for more intense evaluation by NASA. Anticipated
Benefits: The solicitation identifies anti-fog coatings for use in the EMU helmet as an immediate need. As the coating and coating method have been shown to be substrate agnostic, it can be easily applied to other materials (glass, metals, fabrics) that require ant-fog functionality. More generally, the ability to deposit dozens of different materials with tunable porosity (and thus tunable refractive index, dielectric constant, and heat transfer properties) onto a variety of substrates will undoubtedly enable new applications not yet considered. The company is currently engaged with leading manufacturer of polycarbonate lenses do develop a coating with similar functionality. The company has previously engaged with skylight manufactures and commercial refrigeration companies who want to reduce/eliminate the appearance of condensation. A durable anti-fog coating is a potential solution to both problems.
