waessrige paste liquid, a preussischblaupigments

摘要

A fluid aqueous paste of a Prussian blue pigment containing not more than 0.6% oxalic acid or a water-soluble salt thereof, and no more than 0.3% of a formaldehyde-naphthalene sulphonic acid condensate, consisting essentially of a methylene-bis-naphthalene sulphonate, based on the weight of dry pigment, may be obtained by agitating, milling or homogenizing an aqueous paste of a Prussian blue pigment (preferably a press-paste or filter-cake) with the two dispersing agents, and, if desired, extra water. An example is given.ALSO:A fluid aqueous paste of a Prussian Blue pigment containing not more than 0.6% oxalic acid or a water-soluble salt thereof, and not more than 0.3% of a formaldehyde-naphthalene sulphonic acid condensate, consisting essentially of a methylene-bis-naphthalene sulphonate, based on the weight of dry pigment, may be obtained by agitating, milling or homogenizing an aqueous paste of a Prussion Blue pigment (preferably a press-paste or filter cake) with the two dispersing agents, and, if desired, extra water. The pastes may be used in the manufacture of coating compositions, e.g. wallpaper manufacture, in paper dyeing, and in the manufacture of water-borne paints.