Many Noodler's inks are waterproof and have served me well even for legal docs.
I've even found a bunch of other inks that aren't advertised as waterproof/resistant that ended up to be waterproof depending on the paper. For example J. Herbin Perle Noire on meh paper.
I do fine with them as an everyday carry, my gripe is mainly when I get a new pen, paper or ink knowing that a paper might not like a certain pen or ink.
First one is certified document proof, the others work the same, just that the used pigments are not as hardened against chemicals to allow strict iso certification.
They are both fast at drying and once dry, won't give a inch to water. Not even coloring the water and marking the rest of the paper, where it flowed.
I've even found a bunch of other inks that aren't advertised as waterproof/resistant that ended up to be waterproof depending on the paper. For example J. Herbin Perle Noire on meh paper.
I do fine with them as an everyday carry, my gripe is mainly when I get a new pen, paper or ink knowing that a paper might not like a certain pen or ink.