Tolonate HDB 75 MX hardener is an aliphatic polyisocyanate compound of 75% solids with methoxypropyl acetate and xylene. HDB 75 MX is usually used in combination with hydroxylated polymers, especially polyester and polyacrylates, to prepare two-component systems for air-absorbing coatings, which results in mechanical and chemical resistance and resistance to corrosion.