Pigment dispersion, water-based pigment dispersion liquid, and inkjet recording ink and method for producing water-based pigment dispersion liquid

A method for producing a water-based pigment dispersion liquid, the method comprising:

• kneading a mixture containing a bis-acetoacetallylide pigment (a), a styrene-acrylic acid copolymer (b), a basic compound (c), a humectant (d), and a kneading aid (e) to prepare a pigment composition which is in a solid form at room temperature;
• and
• dispersing the pigment composition in a water-based medium,
• wherein the kneading aid (e) comprises
• a surfactant composed of a compound represented by general formula (1)
• and/or
• a surfactant composed of a mixture comprising
• a compound represented by general formula (2)
• a polyoxyethylene alkyl ether whose alkyl group has 12 to 14 carbon atoms, and/or
• an ether compound represented by general formula (3)
• wherein the kneading aid (e) has a hydrophile-lipophile balance (HLB) value of 8 to 12,
• wherein the mass ratio (e)/(a) of the kneading aid (e) to the bis-acetoacetallylide pigment (a) is 0.5/100 to 7/100,
• wherein the acid value of the styrene-acrylic acid copolymer (b) is 145 to 175,
• wherein, in formula (1), R1, R2, R3 and R4 each independently represent a linear or branched alkyl group having 1 to 8 carbon atoms in its main chain, and m and n each independently represent an integer of 0 to 20 and do not represent 0 at the same time,
• wherein, in formula (2), R1, R2, R3 and R4 each independently represent a linear or branched alkyl group having 1 to 8 carbon atoms in its main chain, and
• wherein, in formula (3), q represents an integer of 1 to 30 and R5 represents a linear or branched alkyl group having 7 to 11 carbon atoms.