Inkjet ink and inkjet recording device
An inkjet ink includes a quinacridone pigment, a pigment dispersion resin, and a water-soluble organic solvent. The pigment dispersion resin includes an adsorbed resin adsorbed on the quinacridone pigment and an unadsorbed resin that is not adsorbed on the quinacridone pigment. A ratio of the unadsorbed resin to the pigment dispersion resin is 40 mass % or less. The water-soluble organic solvent includes a predetermined water-soluble organic solvent having an octanol/water partition coefficient Log P of 0.00 or more. A content ratio of the predetermined water-soluble organic solvent with respect to a mass of the inkjet ink is 15 mass % or more and 40 mass % or less. A sulfur concentration in a supernatant liquid obtained by centrifuging the inkjet ink at 1,050,000 G for 3 hours is 0.5 ppm or more and 2.0 ppm or less.
1 . An inkjet ink, comprising:
a quinacridone pigment;
a pigment dispersion resin; and
a water-soluble organic solvent,
the pigment dispersion resin including an adsorbed resin adsorbed on the quinacridone pigment and an unadsorbed resin that is not adsorbed on the quinacridone pigment,
a ratio of the unadsorbed resin to the pigment dispersion resin being 40 mass % or less,
the water-soluble organic solvent including a predetermined water-soluble organic solvent having an octanol/water partition coefficient Log P of 0.00 or more,
a content ratio of the predetermined water-soluble organic solvent with respect to a mass of the inkjet ink being 15 mass % or more and 40 mass % or less,
a sulfur concentration in a supernatant liquid obtained by centrifuging the inkjet ink at 1,050,000 G for 3 hours being 0.5 ppm or more and 2.0 ppm or less.
2 . The inkjet ink according to claim 1 , further comprising a sulfur compound represented by the formula (1):
wherein, in the formula (1), n represents an integer of 1 or more and 3 or less, m represents an integer of 1 or more and 3 or less, and X represents a metal ion.
3 . The inkjet ink according to claim 2 , wherein
X in the formula (1) represents Al 3+ or Mg 2+ .
4 . The inkjet ink according to claim 2 , wherein
a content ratio of the sulfur compound represented by the formula (1) with respect to a total mass of the quinacridone pigment and the sulfur compound represented by the formula (1) is 3 mass % or more and 5 mass % or less.
5 . The inkjet ink according to claim 1 , wherein
the predetermined water-soluble organic solvent is 3-methyl-1,5-pentanediol, triethylene glycol monobutylether, 1,2-pentanediol, or diethylene glycol monobutylether.
6 . An inkjet recording device, comprising:
the inkjet ink according to claim 1 ;
a conveying unit that conveys a recording medium; and
a line head,
the line head ejecting the inkjet ink to the recording medium.