"Crosslinker 105 " is a special adhesion additive used for our water-based Sebek inks. This colour additive improves colour adhesion on particularly tricky surfaces. It also helps the ink become water-resistant. Please noteThere is a use-by date on the ink once Crosslinker has been added to it, as Crosslinker will cause the ink to harden over time. For best results mix up only the desired batch quantities.  Recommended ratio: 2-3% Sold in 100ml quantities.