Inkjet ink and inkjet recording device

1. An inkjet ink comprising:

a water-dispersible colorant;

a surfactant;

a penetrating agent;

a water-dispersible resin;

a wetting agent comprising at least one polyhydric alcohol having an equilibrium moisture content of 30% by mass or higher at 23° C., 80% RH;

a compound of formula (1);

water; and

at least one selected from the group consisting of a compound of formula (2), a compound of formula (3), and a compound of formula (4),

wherein the water-dispersible colorant is at least one selected from the group consisting of a self-dispersible pigment, a pigment dispersed by a pigment dispersing agent, and resin particles each comprising a pigment,

wherein a total amount of the water-dispersible colorant and the water-dispersible resin is from 8% by mass to 35% by mass, and

wherein a mass ratio of the water-dispersible resin to the water-dispersible colorant is from 2 to 8:

wherein R 1 is a C4-C6 alkyl group,

wherein R 2 is a hydrogen atom, a methyl group, or an ethyl group, and R 3 is a C1-C4 alkyl group,

wherein R 4 is either a methyl group or an ethyl group, and R 5 is a hydroxyl group, a C1-C8 alkyl group, a cycloalkyl group, or an aryl group, and

wherein R 6 and R 7 are each independently a C1-C8 alkyl group.

2. The inkjet ink according to claim 1 , further comprising a compound of formula:

CH 3 OCH 2 CH 2 CON(CH 3 ) 2 .

3. The inkjet ink according to claim 1 , wherein the water-dispersible resin is an acryl-silicone resin, a fluororesin, or a combination of the acryl-silicone resin and the fluororesin.

4. The inkjet ink according to claim 1 , comprising a self-dispersible pigment, and wherein the self-dispersible pigment is anionic.

5. The inkjet ink according to claim 1 , wherein the surfactant is a silicone-based surfactant, a fluorine-based surfactant, an acetylene alcohol-based surfactant, or any combination thereof.

6. The inkjet ink according to claim 1 , wherein the ink has dynamic surface tension of 35 mN/m or less at 25° C., with a surface lifetime of 15 ms as measured by the maximum bubble pressure method.

7. An inkjet recording device, comprising:

an ejecting unit configured to eject an inkjet ink,

wherein the inkjet ink comprises:

a water-dispersible colorant;

a surfactant;

a penetrating agent;

a water-dispersible resin;

a wetting agent comprising at least one polyhydric alcohol having an equilibrium moisture content of 30% by mass or higher at 23° C., 80% RH;

a compound of formula (1);

water; and

at least one selected from the group consisting of a compound of formula (2), a compound of formula (3), and a compound of formula (4),

wherein the water-dispersible colorant is at least one selected from the group consisting of a self-dispersible pigment, a pigment dispersed by a pigment dispersing agent, and resin particles each comprising a pigment,

wherein a total amount of the water-dispersible colorant and the water-dispersible resin is from 8% by mass to 35% by mass, and

wherein a mass ratio of the water-dispersible resin to the water-dispersible colorant is from 2 to 8:

wherein R 1 is a C4-C6 alkyl group,

wherein R 2 is a hydrogen atom, a methyl group, or an ethyl group, and R 3 is a C1-C4 alkyl group,

wherein R 4 is either a methyl group or an ethyl group, and R 5 is a hydroxyl group, a C1-C8 alkyl group, a cycloalkyl group, or an aryl group, and

wherein R 6 and R 7 are each independently a C1-C8 alkyl group.

8. The inkjet ink according to claim 1 , comprising a compound of formula (2).

9. The inkjet ink according to claim 1 , comprising a compound of formula (3).

10. The inkjet ink according to claim 1 , comprising a compound of formula (4).