So I’ve been thinking a bit more on the copic/leather thing, and I still have some reservations as to their longevity with this medium. Don’t get me wrong - they’re definitely high quality markers - but I’m not convinced that they’re the right tool for this job. Hopefully the following photos will help to illustrate why that is.
So here’s a little scrap that I hit with three different types of color - alcohol dye (made for leather), alcohol ink, and copic marker:
From the top view, you can see that the two alcohol colors have deeper saturation, while the copic color is paler and more translucent (almost like watercolor). That’s not necessarily a bad thing - I’m pretty sure it’s the desired effect/style of copic color, and I do think it’s quite pretty - but the side views hint at a potential problem.
This is the alcohol dye (made specifically for leather), which I swiped on ever so lightly with a dauber. Note how the color seeps through the top layer of the leather, down about 1/2 way through the fiber:
The alcohol ink had similar results … though this ink is a lot more expensive than the leather dye, and it did not saturate quite as nicely:
The copic marker barely saturates. It sits on the top/surface layer, and does not penetrate down into the fibers at all. I retested this on another piece of leather, going over it multiple times with the marker, and had the same effect:
So over time as that piece of leather flexes and stretches, I suspect you’ll start to see holidays in the color. I also get the feeling that you’ll see a bit of fading with these. You might be able to minimize fading simply by sealing it well, but just based on experience (and many, many failures along the way) I think these colors will fade and/or skip over time. I could be wrong - and I sincerely hope that I am, because they’re beautiful colors - but I just don’t think they’re ideal for leather. I know some amazing leather crafters, and I’ll run it by them and see what they think. But the fact that I don’t see many established leather pros selling work done with these markers raises a red flag for me as far as long term durability.
YMMV. Perhaps they just haven’t been discovered by many old school leatherworkers yet. They may last beautifully - and depending on the project, it might not even matter. If it’s just an experiment or a one off gift for someone close to you (so you can touch up the color if it starts to fade) no biggie. I certainly had fun playing with them, and I do like the results … but personally my scrap experiments will sit in a sunny corner of my studio for some time before I consider selling leatherwork colored with these.