Aqueous, colloidal gas black suspension containing: (a) a gas black, (b) an azo compound of the formula 1 ##STR00001## (c) and water. The aqueous, colloidal gas black suspension is produced by dispersing the gas black and the azo compound of the formula 1 in water. It can be used in the production of inks, ink-jet inks, surface coatings and colored printing inks.