|Nano Faraz Sepahan|
Construction Masonry MaterialsWaterproof Solution
Inhibition of changing the appearance of metallic surfaces Without chemical and harmful effect Easy to clean Durable water repellent Long-term stability Resistance to UV radiation Corrosion resistant
Continuous contact of water to various materials, including metals, ceramics, and building materials in our different work and living environments can be a disaster and can affect the beauty of surfaces in addition to causing financial damage. Nowadays, the use of metallic facades such as aluminum alloys with special coatings has been the focus of attention for a number of reasons, such as beauty and reducing energy consumption and, of course, the increasing of sunlight reflection in hot cities. The body of vehicles is other important usage of metals that need to be clean and beautiful. On the other hand, the use of metals in places such as toilets and kitchens such as hood, stove and refrigerator is associated with exposure to moisture and water. Dust and rain stains on the surface of the building and the body of cars, and spots caused by splashing water or drying due to chlorine in the water inside of the bathroom, are probable on the metal surface. Cleaning the building and car body using water is a common but costly method. A good alternative to these methods is applying hydrophobic coatings.
Applying of these coatings causes water particles to not adhere to the surface and also to remove dirt or particles from the surface by water droplets. The use of colloidal coatings containing nanoparticles creates a very high contact angle (usually over 100 degrees) as well as low surface energy and reduces the capillary property between the water droplets and the surface and creates a spherical shape in the droplets which results in easy moving on the surface. As a result, stains on the surface are prevented and no need for continuous washing and use of acidic detergents, as well as preventing blurring of metallic surfaces. Also, these coatings increase the metal's resistance to corrosion and rust.
Due to the embeding of nanoparticles in the polymeric base, the proper hydrophobic property is created on the surface of metals. Micro and nano sized roughness due to the presence of nanoparticles, reduce the surface adhesion force between droplets of water and the surface of the metal. On the other hand, the results of measurements of water contact angle are given in the table below. Increasing the contact angle by applying coatings containing nanoparticles changes the water droplets to a sphere shape condition and prevent them from sticking to the metallic surface. Based on article 4-4 of the Iran-ISO national standard number 80004-2, the presence of silica nanoparticles in this product is confirmed.