Inkjet ink, method of manufacturing inkjet ink, ink cartridge, and inkjet recording device

A method of manufacturing an inkjet ink comprising:

• adjusting a pigment dispersion element in which a pigment is dispersed in water;
• and
• manufacturing the inkjet ink using the pigment dispersion element,
• wherein the inkjet ink comprises water, a hydrosoluble organic solvent, the pigment, polyvinyl pyrolidone;
• and a copolymer,
• wherein the copolymer comprises a structure unit represented by Chemical formula 1,
• where R1 represents a hydrogen atom or a methyl group, R2 is an alkyl group having one to four carbon atoms, M1+, M2+, M3+, and M4+ each, independently represent protons, alkali metal ions, or organic ammonium ions, and
• a structure unit represented by Chemical formula 2,
• where R3 represents a hydrogen atom or a methyl group,
• a structure unit represented by Chemical formula 3,
• where R4 represents a hydrogen atom or a methyl group, or
• a structure unit represented by Chemical formula 4,
• where R5 represents a hydrogen atom or a methyl group,
• wherein the pigment dispersion element comprises the copolymer.