Dark colours absorb high levels of IR light, which is converted in to heat energy and leads to excessive heat build up in PVCu profiles. To overcome these issues Berger-Zobel have incorporated IR reflective pigments into their Zowo-plast ZP formulations. Test have been carried out on these to compare the performance of the Anti-Heat Zowo-Plast product Vs standard products and white PVCu.
Standard and Anti-Heat versions of Zowo-Plast 2450 colours were applied to white uPVC at 150µ and dried for 24hrs at 20°C and 50% humidity. Samples were tested under the ASTM D 4803 Standard Test Method for Predicting Heat Build Up in PVCu Building Products, with the sun simulated by a defined IR lamp. Temperature was measured as an increase above the ambient temperature of the laboratory.
Control: White uPVC
RAL Colours: RAL 7037 – Dusty grey
RAL 8007 – Fawn Brown
RAL 9004 – Signal Black
|Heat Build Up* Standard Colour [°C]||Heat Build Up* ANTI-Heat Colour [°C]||Reduced heat build up due to ANTI-HEAT [°C]|
RAL 7037 (grey)
RAL 8007 (brown)
RAL 9004 (black)
*measured as the temperature above ambient
In an ambient temperature of 20°C and direct exposure to a simulated sunlight source
- Darker colour shades without Anti-Heat technology exhibited a >25°C increase in temperature compared to white PVCu. which could lead to severe expansion and potential warping.
- The heat build-up seen in the same colours shades that included the Anti-Heat Technology was between 16 and 21°C lower than seen in standard colours
- The benefit of using the Anti-Heat Technology, was to restrict the temperature increase to a maximum of just +6°C over the uncoated white PVCu sample