The colouring results from a very thin and transparent oxide layer on the surface of the metal. Depending on the thickness of the layer, the spectral or rainbow colours arise through double reflection of the incident light and interference in the reflected light, as with a thin film of oil on water. Brown and black colours can also be produced on stainless steel. The interference layers on the stainless steel consist of chromium oxide, on titanium and zircon from the oxides in the basic material. The colouring results from chemical treatment in an immersion bath in the case of stainless steel and electrolytically through anodic oxidation in the case of titanium and zircon. The oxide layers adhere to the basic material and are flexible and ductile.
- are resistant to atmospheric conditions and aging
- do not crack or flake off
- are more resistant to corrosion and chemicals than the uncoloured basic material
- show off the structure and finish of the basic material to full effect
Separated into decorative (D) and technical (T) application:
- Architecture (D) for façades, lift cabins and ceiling cladding
- Signs and front panels (D)
- Medical technology (T) for instruments and implants
- Mounting elements(D)
- Solar absorbers (T)
- Corrosion protection (T)
- Glare shields (T)
- Lubricant layer ® (T)
- Insulation (T)
POLIGRAT supplies complete installations, including environmentla technology, for customer use. The company also offers the colouring of customer parts as a service supplied its by own sub-contractors.