Pigments and related methods

Abstract

Pigments and related methods are generally described. In some embodiments, the pigments comprise azo pigments. According to some embodiments, the pigment is non-halogenated. In certain embodiments, the method comprises a method of forming a pigment (e.g., an azo pigment). For example, in some cases, the method comprises reacting a primary amine and a nitrite ester (e.g., tert-butyl nitrite) in the presence of an acid (e.g., p-toluenesulfonic acid) and an organic solvent (e.g., ethyl acetate) to form a diazonium salt. In certain instances, the method comprises forming a pigment by reacting the diazonium salt with a coupler (e.g., in a biphasic mixture comprising the organic solvent and water). According to some embodiments, the method does not involve any halogenated compounds. In accordance with certain embodiments, the method results in reduced toxic (e.g., carcinogenic) byproducts and/or toxic (e.g., carcinogenic) degradation products.

Dependencies are inferred from the claim text.