Like Lady MacBeth, I am plagued by spots that will not come out. After trying to find some decent clothes for a doctor's appointment, I vowed that this will change. So, I investigated the wash-ability of several common inks on a white cotton T-shirt.
1. Noodler's Heart of Darkness, a "bulletproof" fountain pen ink
2. Higgins Eternal
2. Sumi Moonpalace
3. Walnut ink, from crystals
4. Iron gall ink (my own pomegranate ink)
5. Chesterfield archival, a iron gall ink with blue dye for fountain pens.
First pic-
after ink dried for about 30 minutes.
Second pic-
After standard wash in washing machine, warm water, detergent was All with Stainlifters
Third pic-
After 5 hour soak in Oxiclean, 3 scoops to 1 gallon, run through a washing machine with no detergent
Fourth--
Run through washing machine, small load, with 1/2 c bleach
Results-
Avoid HOD, Higgins Eternal and Sumi if you want to get it out of your clothes. Really permanent.
Iron gall and walnut crystals will come out a bit with Oxiclean, but not all.
If you can bleach, then walnut crystal ink is your best bet.
Still, I am not happy with this. I have ordered Winsor and Newton black ink and Manuscript black ink. Both are claimed to be water soluble and washable. We shall see, on the other side of the T-shirt.