Thanks, Giovanni.

My personal experience is not based on any observation other than a wet pen when I take off the cap, one day later, or even several weeks or a month later. Success with Pilot Falcon Resin; Waterman Phileas; the original TWSBI 530; and most of my piston fillers, i.e. Pelikans.

I have little success with Chinese pens like Hero and/or Duke.