| abstract |
A process for the production of a pigment composition comprising precipitating a pigment coupling component from alkaline solution by adding to it an acid, in the presence of a pre-formed, water-soluble azo dyestuff; and subsequently coupling the precipitated coupling component, containing the azo dyestuff, with a pigment diazo or tetrazo component, ensuring that at no time is any substantial amount of uncoupled diazo or tetrazo component present, to form a pigment composition containing the water-soluble azo dyestuff. |