My experiment to determine which drawing pens are fade proof has been going on for almost 5 years now. The goal of the experiment was to determine which inks resist fading when exposed to UV light. I also thought I should test a few of the pens that are used by artists that aren't marketed as drawing pens, such as Sharpies and ballpoint pens.
I needed to find a place to store the paper where it would be exposed to sunlight for the entire day. At first I thought I could just tape it to a window inside of my house but some windows block the UV light, which would defeat the purpose of this test.
I decided to use the interior of my car is a test chamber where it would also be exposed to extreme changes in temperature and humidity. Most collectors and artists exhibit their artwork indoors where the light is less intense, but the concept is that exposing the ink to intense UV light will mimic the long term effects of exposure to lower levels of UV light.
With each pen, I drew lines on a piece of paper, and labeled it. When I was done I cut the sheet of paper in half. I stored one half of it inside my car and the other half in complete darkness. I photographed the results in 2013 and in 2016, see the photos below.
