Octopus Fluids Alcohol Inks are acid-free Alcohol Inks are smudge- and waterproof, but can be re-liquefied or removed at any time using isopropyl alcohol. can be used on almost all smooth, non-porous materials. It is best suited to specially coated papers (e.g. Yupo Paper), glass, metal, ceramics, porcelain, and stone. They are also suited to colouring your resin artworks or resin jewellery.