Pigment compositions having a reduced content of aryl amines or n-arylacetoacetamides and oxidation methods for producing the same

A method comprising:

• providing a pigment dispersion comprising an N-arylacetoacetarylide pigment composition dispersed in an aqueous phase in the presence of a polymeric dispersant and/or at least one surfactant, the N-arylacetoacetarylide pigment composition comprising a diazonium coupling product of a first aryl amine and an N-arylacetoacetamide formed from a second aryl amine;
• wherein the N-arylacetoacetarylide pigment composition comprises at least some residual N-arylacetoacetamide that has not undergone diazonium coupling and/or at least some residual second aryl amine that has not reacted to form the N-arylacetoacetamide and/or has hydrolyzed from the N-arylacetoacetamide;
• contacting the pigment dispersion with an oxidant at an alkaline pH at a temperature and for a time sufficient to decrease a concentration of the residual N-arylacetoacetamide and/or the residual second aryl amine in the N-arylacetoacetarylide pigment composition;
• wherein the dispersion remains stable after being contacted with the oxidant.