Base metal pigment, aqueous base metal pigment dispersion liquid, and aqueous ink composition
Disclosed herein is a base metal pigment, which is used for an aqueous ink composition containing water as a part of a solvent, in which the base metal pigment is surface-treated with a fluorine-based compound, and has a zeta potential of greater than or equal to −50 mV and less than or equal to −15 mV, as measured by an ultrasonic zeta potential measurement device, in a pH range of greater than or equal to 5 and less than or equal to 10.
1. A base metal pigment, which is used for an aqueous ink composition containing water as a part of a solvent,
wherein the base metal pigment is surface-treated with a fluorine-based compound selected from the group of fluorine-based phosphonic acid, fluorine-based carboxylic acid, fluorine-based sulfonic acid, and salts thereof, and has a zeta potential of greater than or equal to −50 mV and less than or equal to −15 mV, as measured by an ultrasonic zeta potential measurement device, in a pH range of greater than or equal to 5 and less than or equal to 10.
2. The base metal pigment according to claim 1 ,
wherein the difference between the maximum value and minimum value of the zeta potential in a pH range of greater than or equal to 5 and less than or equal to 10 is less than or equal to 15 mV.
3. The base metal pigment according to claim 1 ,
wherein the base metal pigment has a scale-like shape.
4. The base metal pigment according to claim 1 ,
wherein the fluorine-based compound has a perfluoroalkyl group.
5. The base metal pigment according to claim 4 ,
wherein the perfluoroalkyl group has a carbon number of 1 to 6.
6. The base metal pigment according to claim 1 ,
wherein heat treatment is performed when the base metal pigment is surface-treated with the fluorine-based compound.
7. An aqueous base metal pigment dispersion liquid, comprising:
a base metal pigment surface-treated with a fluorine-based compound selected from the group of fluorine-based phosphonic acid, fluorine-based carboxylic acid, fluorine-based sulfonic acid, and salts thereof; and
water as a part of a solvent,
wherein the aqueous base metal pigment dispersion liquid has a zeta potential of greater than or equal to −50 mV and less than or equal to −15 mV, as measured by an ultrasonic zeta potential measurement device, in a pH range of greater than or equal to 5 and less than or equal to 10.
8. The aqueous base metal pigment dispersion liquid according to claim 7 ,
wherein a solvent, from which the base metal pigment was removed by centrifugal separation, has a specific dielectric constant of greater than or equal to 45 and less than or equal to 60, as measured by an alternate current-type dielectric constant measurement device, at a temperature of 23° C. and a frequency of 10 kHz.
9. An aqueous ink composition, comprising:
a base metal pigment surface-treated with a fluorine-based compound selected from the group of fluorine-based phosphonic acid, fluorine-based carboxylic acid, fluorine-based sulfonic acid, and salts thereof; and
water as a part of a solvent,
wherein the aqueous ink composition has a zeta potential of greater than or equal to −50 mV and less than or equal to −15 mV, as measured by an ultrasonic zeta potential measurement device, in a pH range of greater than or equal to 5 and less than or equal to 10.
10. The aqueous ink composition according to claim 9 ,
wherein a solvent, from which the base metal pigment was removed by centrifugal separation, has a specific dielectric constant of greater than or equal to 45 and less than or equal to 60, as measured by an alternate current-type dielectric constant measurement device, at a temperature of 23° C. and a frequency of 10 kHz.