Ink, ink stored container, inkjet printing method, and inkjet printing device

An ink storage container comprising:

• an ink;
• and
• a container storing the ink,
• wherein the ink comprises:
• a copolymer that comprises at least one of a structural unit represented by formula (1) below and a structural unit represented by formula (2) below;
• a pigment having an acid value of 15 μmolig or less and represented by formula (3) below;
• water;
• and
• a water-soluble organic solvent,
• wherein in the formula (1), R1 represents a hydrogen atom or a methyl group and L1 represents an alkylene group that comprises from 2 through 18 carbon atoms,
• wherein in the formula (2), R1 represents a hydrogen atom or a methyl group and L2 represents a single bond or —(CH 2)n-O— of which oxygen atom is bound with biphenyl, where n represents an integer of from 2 through 18,
• wherein in the formula (3), R1 represents any one of a hydrogen atom, a halogen atom, an alkyl group that comprises from 1 through 4 carbon atoms, an alkoxy group that comprises from 1 through 4 carbon atoms, a hydroxy group, a nitro group, and an alkyl-substituted or unsubstituted amino group that comprises from 1 through 4 carbon atoms, n represents an integer of from 1 through 5, when n is a plural number, R1 may be identical or different, and R2, R3, and R4 represent an alkyl group that comprises from 1 through 4 carbon atoms.

An inkjet printing device comprising

• an ink discharging unit configured to discharge an ink from a print head to print an image on a print medium,
• wherein the ink comprises:
• a copolymer that comprises at least one of a structural unit represented by formula (1) below and a structural unit represented by formula (2) below;
• a pigment having an acid value of 15 μmolg or less and represented by formula (3) below;
• water;
• and
• a water-soluble organic solvent,
• wherein in the formula (1), R1 represents a hydrogen atom or a methyl group and L1 represents an alkylene group that comprises from 2 through 18 carbon atoms,
• wherein in the formula (2), R1 represents a hydrogen atom or a methyl group and L2 represents a single bond or —(CH 2)n-O— of which oxygen atom is bound with biphenyl, where n represents an integer of from 2 through 18 ,
• wherein in the formula (3 ), R1 represents any one of a hydrogen atom, a halogen atom, an alkyl group that comprises from 1 through 4 carbon atoms, an alkoxy group that comprises from 1 through 4 carbon atoms, a hydroxy group, a nitro group, and an alkyl-substituted or unsubstituted amino group that comprises from 1 through 4 carbon atoms, n represents an integer of from 1 through 5, when n is a plural number, R1 may be identical or different, and R2, R3, and R4 represent an alkyl group that comprises from 1 through 4 carbon atoms.