Nano-pigment inkjet ink composition that has a low odor and is environmentally-friendly

A nano-pigment inkjet ink composition that has a low odor and is environmentally-friendly, comprising:

• N-ethyl pyrrolidone;
• propylene carbonate;
• a glycol ether solvent;
• a pigment;
• a dispersant;
• a resin;
• a plasticizer;
• a surfactant;
• and
• from 0.1 to 3.0 percent by weight, based on total weight of the nano-pigment inkjet composition, of an acidity regulator that is at least one cyclic tertiary amine compound and that is selected from the group consisting of ethyl 1-methyl-piperidine-3-carboxylate, 1-(2-hydroxyethyl)-4-(3-hydroxypropyl)piperidine, 3-(1-piperidinylmethyl)phenol, 1-methyl-3-piperidinemethanol, 4,4′-trimethylene bis(1-piperidine ethanol), N-methyl-3-piperidinol, N-ethyl-3-piperidinol, 4-acetamido-1-benzylpiperidine, 1-methyl-2-piperidinemethanol, 1-(2-hydroxyethyl)piperidine, ethyl 1-piperidinepropionate, 1-piperidinepentanol, tropine, 1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol, 4-hydroxy-1,2,2,6,6,-pentamethylpiperidine, N-methyl-4-piperidone, N-ethyl-4-piperidone, 1-(2-phenylethyl)-4-piperidone, 1-benzyl-4-piperidone, 1,3-dimethyl-4-piperidone, tropanone, 1-(2-hydroxyethyl)pyrrolidine, 3-(dimethylamino)pyrrolidine, 1-pyrrolidino-1-cyclopentene, 1-pyrrolidino-1-cyclohexene, 1-ethyl-3-pyrrolidinol, 1-isopropyl-3-pyrrolidinol, 1-benzyl-3-pyrrolidone, and 1-acetyl-4-(4-hydroxyphenyl)piperazine.