Abstract: Metal chromate and particularly lead chromate pigment compositions exhibiting low dusting characteristics and improved heat stability in thermoplastics are described. The pigment compositions consist essentially of a metal chromate-containing pigment and the combination of certain fatty acid salts with normally liquid ester plasticizers. Lead chromate pigment compositions containing the combination of a zinc salt of a fatty acid with benzoate, phthalate, stearate or phosphate plasticizers are particularly preferred and exhibit reduced dusting as well as outstanding advantages in heat stability not realizable with either the fatty acid salt or plasticizer alone or by silica encapsulation of the pigment particles.

Abstract: Pigmentary compositions comprising an anhydrous crystalline, light-stable nickel chelate of 1-nitroso-2-naphthol, from about 0.10 to 1.0 mole, per mole of the nickel chelate, of certain ester plasticizers and from about 0.05 to 1 part, per part of the anhydrous nickel chelate, of certain fatty acids and/or their salts are described. The compositions have improved texture and dispersibility characteristics and are produced by wetting the hydrated nickel chelate of 1-nitroso-2-naphthol in aqueous medium with the plasticizer and fatty acid and/or its salt, isolating the wetted product and then heating the isolated product until dehydration is complete.