Process for producing azo compounds, pigment dispersion, coloring composition, ink for inkjet recording, coloring composition for color filter, and color filter

A method for producing an azo pigment represented by the general formula (1), comprising:

• preparing a solution comprising a compound represented by the following general formula (2) and an acid;
• and
• conducting azo coupling by bringing the solution into contact with a diazonium salt derived from a heterocyclic amine:
• wherein
• G2 represents a hydrogen atom, an aliphatic group, an aryl group, or a heterocyclic group;
• R21 represents an amino group, an aliphatic oxy group, an aliphatic group, an aryl group, or a heterocyclic group;
• R22 represents a substituent;
• A2′ represents the following general formulae (A-1) to (A-18), (A-20) to (A-28), and (A-30) to (A-32);
• m represents an integer of from 0 to 5;
• n represents an integer of from 1 to 4;
• when n=2, the general formulae (1) and (2) each represents a dimer formed through R21, R22, G2, or A2′;
• when n=3, each of the general formulae represents a trimer formed through R21, R22, G2, or A2′;
• and
• when n=4, each of the general formulae represents a tetramer formed through R21, R22, G2, or A2′:
• wherein
• R51 to R59 each represents a hydrogen atom or a substituent, and adjacent substituents may be connected to each other to form a 5- or 6-membered ring;
• and
• * shows a site connected to the azo group in the general formula (1).