The problem, recall, is getting an archival (or at least photo safe) ink to stick to the back of a resin-coated photograph. Almost anything consumers buy now is resin (polyethylene) coated.
In my last post I discussed that only the Zig Photo Signature pen and the Zig Millenium produced reasonable results. The remaining problems are:
- The Zig Photo Signature smells like a Sharpie, and I am consequently worried that long-term it will yellow and fade like a Sharpie.
- The Zig Millenium must be blotted (a minor hassle) and must dry overnight or it will smear. Even overnight it smears a little.
I found another candidate after looking into India inks. It is Higgins Black Magic Waterproof ink. I wrote for the following test with a toothpick, forgive my crummy picksmanship.
I smeared it with my finger after about 10 minutes, and it was perfect.
The ink is listed by the manufacturer as being acid free, and it would appear to be a pigment ink so it should be more fade resistant than the dye-based solvent solutions. So, by surmise, this ink solves both the previous problems. Whether it is archival or not, compared to resin-coated papers, is not something I have found information on. It is latex based, which may be the same thing sold as acrylic ink, and is likely domestically archival though I would hesitate for museum use.
The downside is that the ink is for use with dip pens or with technical pens. In both cases, after use there is cleanup. Ink could sit in a technical pen for a week, but will dry and ruin the pen if left in long-term.