Liquid developing agent and process for producing the same

A liquid developing agent where a colored chip obtained by heat kneading a pigment with a thermoplastic resin is dispersed by wet pulverization in an electrically insulating hydrocarbon solvent dissolving at least one pigment dispersant selected from the group consisting of the following modified novolak resin (A) and copolymer (B) having an aromatic ring and a ring-opened structure of an epoxy group by a hydroxycarboxylic acid-derived carboxyl group:

• Modified novolak resin (A):
• a modified novolak resin having a novolak resin-derived aromatic ring and at least one group shown by a general formula (1) by ring-opening of an epoxy group by a hydroxycarboxylic acid-derived carboxyl group:
• wherein an oxygen atom at the far left is derived from an oxygen atom contained in an aromatic hydroxyl group of a novolak resin, W1 and X1 each independently represent a divalent hydrocarbon group with carbon numbers of 1 to 19, i and j each independently represent an integer of i=1 to 30 and j=0 to 30, and R1 represents a hydrogen atom or a methyl group.
• Copolymer (B):
• a copolymer with a weight-average molecular weight of 3000 to 100000, having, in said copolymer, the amount corresponding to at least 10 mol % of the recurring unit shown by a general formula (2), and the amount corresponding to at least 10 mol % of at least one kind selected from the recurring units shown by a general formula (3) and a general formula (4):
• wherein W2 and X2 each independently represent a divalent hydrocarbon group with carbon numbers of 1 to 19, p and q each independently represent an integer of p=1 to 30, and q=0 to 30, R2, R3 and R4 each independently represent a hydrogen atom or a methyl group, R5 represents a hydrogen atom or a halogen atom, R6 and R7 each independently represent a hydrogen atom, a hydrocarbon group with carbon numbers of 1 to 5, an alkoxy group with carbon numbers of 1 to 5, an aryloxy group with carbon numbers of 6 to 10, or a halogen atom, R8 represents a hydrogen atom or a methyl group, and R9 represents a direct bond or a methylene group.