Left: Lightfast test swatches made of three Art Kure Brush Pens: Delft Blue, Blue, and Brown. I no longer have the pens so I don't know the exact name of the dark blue and brown. I labeled the Delft Blue strokes with DB everywhere as I wanted to be sure to know after the fading test which blue was which. Click to view an enlargement.
Friends and students know I love to use the Pentel Color Brush even though it isn't lightfast. You can read my comments about that brush pen in my January 15, 2009 post which also contains links to artwork made with it.
Well a couple years ago when I first saw the Art-Kure Brush Pen in a supply catalog I thought, since they referred to it as a "watercolor system," that it might actually be an archival tool…
THESE PENS ARE NOT LIGHTFAST as you can see from the lightfast test. Don't be lured in by their snazzy nomenclature in the promotional copy. This is not a "watercolor" tool or "fine art" tool. This tool produces fugitive results. You need to be aware of that to make a choice about whether you use it.
Now of course just because this "paint" fades it doesn't mean you can't use this tool. Just like the Pentel Color Brush you can sketch with these pens (which look like Niji Waterbrushes) and then you can touch the lines with water and blend them and get shadows and fun effects. More fun is to sketch with one of these pens and then paint over the lines with gouache and let the lines blend and bleed into the paint for some interesting mixes.
I use these pens when I go to life drawing. I find them very useful for the beginning 2-minute warm up poses. I don't care if those drawings fade. If I get one that I really like I tend to come home and scan it or make a photocopy of it (thus turning the lines black).
But if you are going to use these pens I think it's good to know how drastically they will change. I recommend you spend your time and artistic effort using an archival alternative: artist quality watercolors and a brush. (Calligraphers and scrapbookers be particularly wary on work you want to be long lived! A moment of convenience could lead to heartache later on.)