Accelerated weathering test for Qualicoat

EN ISO 11341

Luminous intensity: 550 ± 20 W/m2 (290 – 800 nm)
Black standard temperature: 65 ± 5°C
Demineralised water: maximum 10 μS
Special UV filter (290 nm)
Cycles of 18 minutes in a wet medium and 102 minutes in a dry medium.
After 1000 hours exposure (2000 hours for class 3), the test panels should be rinsed with demineralised water and checked for:

• Gloss variation: EN ISO 2813 angle of incidence 60°
• Colour change: ΔE CIELAB formula according to ISO 7724/3, measurement including specular reflection.

3 colour measurements are to be made on the test panels before and after the accelerated weathering test.

For class 3 powder coatings gloss and colour variation shall be checked every 500 hours.

REQUIREMENTS:
Gloss retention: the loss of gloss after the accelerated weathering test shall not be greater than 50% of the initial value, or 10% for class 2 and class 3 powder coatings.

An additional visual assessment will be carried out for

• organic coatings with an original gloss value of less than 20 units;
• organic coatings with structured appearance in all gloss categories;
• organic coatings with a metallic or metallised effect (see appendix A4).

Colour change: according to the ΔE values stipulated in the annexed table. For class 2 and class 3 powders, the colour change ΔE shall not be greater than 50% of the limits prescribed in the annexed table.