Technologies of painting aluminum profiles
We distinguish between two basic technologies of painting aluminum profiles. These are anodization and plasticization.
Anodizing
is the name for the process of surface protection of aluminum against corrosion. In this process, aluminum is coated with a thin layer of oxide (about 1 micrometer thick), which protects it from further oxidation. However, since the thickness of the layer is not thick enough and is not aesthetically acceptable, the aluminum profile undergoes a phase oxidation treatment in which the thickness of the protective layer increases to 12 to 30 micrometers.
Anodized aluminum is very resistant to acids, but it is not resistant to bases and to physical damage - "scratches". Special care should be taken to ensure that no e.g. remains on the surface of the anodized aluminum profile. plaster, plaster, lime for painting walls, because damages are inevitable, they can be extremely difficult to remove and only with the help of special sprays for metal.
Plasticization
is today the most common way of surface protection of aluminum. The plasticization process is very simple. First, the aluminum surface is degreased by dipping it in a sodium hydroxide solution, after which a primer is applied, which is usually chromium oxide. In the next stage, highly positively charged paint powder is applied with special diffusers. Since the aluminum profiles that we plasticize are oppositely charged, the powder adheres firmly to the surface of the aluminum. The aluminum profiles powdered in this way are fed into the furnace where they are heated to 180 to 200ºC. As a result of heating, the powder molecules melt and polymerize, forming a plastic layer 50 to 70 µ thick.
