Do the UV properties of the 071 series UV shield degrade over time?

When exposed to direct sunlight, you will see yellowing over the years since the UV additive can only do so much. However: the attack is confined to maybe 20 microns to the surface of the plastic, the bulk stays protected. This is why you can retain many tensile properties but do lose some notched izod.

You can see the effect with accelerated weathering on a transparent grade (in this case LED2643, which is similar to 2407 but with higher light transmission). 1000 Joules is about 1 year Florida/Arizona, it will yellow slowly over time, then eventually stabilizes (Figure 1).

For interior uses, where sunlight goes through a window, yellowing is typically never an issue.

               Figure 1: Outdoor UV exposure

Category: Eye & Face Protection
Tags: 071, 071AF, 079, UV, UV properties, UV protective