Setareh 3, LED Street Lighting

Hydrophobic lights used for outdoor applications

Particle size less than 100 nm Modified silica particles with semi spherical morphology The average contact angle will be 105 degree after application of the solution containing silica nanoparticles Reduction of surface tension and capillarity causing hydrophobic properties

This product is the outdoor light bulb which is covered by hydrophobic silica nanoparticles and makes easy-clean surfaces. The surface hydrophobicity refers to the processes in which the surfaces of substrates are modified by hydrophobic compounds. Hydrophobicity is one of the physical properties of a material. Due to its micro or Nano metric roughness, hydrophobic material avoids absorbing and penetrating of water onto a surface causing water to slip and drip. For achieving hydrophobic surfaces, a surface with low surface tension and appropriate microstructure is needed. Silanes are silicone chemicals which have a sensitive hydrolytic center that can react with inorganic substrates such as glass to form stable covalent bonds, and also have organic replacement properties that can alter the physical interactions of the substrate. The reaction of the silanes consists of four steps. Firstly, hydrolysis is carried out in three main groups. Then, desublimation occurs to get oligomer. Next, these oligomers form hydrogen bonds with OH group of substrate. Finally, the covalent bonds will form during baking or dying by water loss. These reactions and initial hydrolysis can be done simultaneously.