Coloring liquid, ink tank, recording unit, recording apparatus and recording method

An ink tank comprising:

• an ink storage portion;
• and
• a coloring liquid contained in the ink storage portion;
• wherein said coloring liquid includes at least one colorant compound having a structure represented by the general formula (1) below:
• wherein
• each of R1 through R4 independently denotes a hydrogen atom, an alkyl group that may be substituted, an aryl group that may be substituted or an aralkyl group that may be substituted, each of R5 and R6 independently denotes a hydrogen atom or an alkyl group and each of R7 and R8 independently denotes a hydrogen atom, a sulfonic acid group, an amino group that may be substituted or —SO2NR9R10, wherein each of R9 and R10 independently denotes a hydrogen atom, an alkyl group, an aryl group or an aralkyl group and may form a heterocycle with a nitrogen atom;
• n denotes an integer between 1 and 3;
• if neither R7 nor R8 is —SO2NR9R10, at least one of said R1 through R4 is an alkylene group, an arylene group or an aralkylene group having —SO2NR9R10 as a substituent;
• and An denotes a counter anion, which is not necessary when a counter anion exists in the molecule.

A recording unit comprising:

• an ink storage portion;
• a coloring liquid;
• and
• a head section for ejecting droplets of the coloring liquid;
• wherein said coloring liquid includes at least one colorant compound having a structure represented by the general formula (1) below:
• wherein
• each of R1 through R4 independently denotes a hydrogen atom, an alkyl group that may be substituted, an aryl group that may be substituted or an aralkyl group that may be substituted, each of R5 and R6 independently denotes a hydrogen atom or an alkyl group and each of R7 and R8 independently denotes a hydrogen atom, a sulfonic acid group, an amino group that may be substituted or —SO2NR9R10, wherein each of R9 and R10 independently denotes a hydrogen atom, an alkyl group, an aryl group or an aralkyl group and may form a heterocycle with a nitrogen atom;
• n denotes an integer between 1 and 3;
• if neither R7 nor R8 is —SO2NR9R10, at least one of said R1 through R4 is an alkylene group, an arylene group or an aralkylene group having —SO2NR9R10 as a substituent;
• and An denotes a counter anion, which is not necessary when a counter anion exists in the molecule.

An ink-jet recording apparatus comprising:

• a coloring liquid;
• and
• an ink-jet recording head for ejecting the coloring liquid;
• wherein said coloring liquid includes at least one colorant compound having a structure represented by the general formula (1) below:
• wherein
• each of R1 through R4 independently denotes a hydrogen atom, an alkyl group that may be substituted, an aryl group that may be substituted or an aralkyl group that may be substituted, each of R5 and R6 independently denotes a hydrogen atom or an alkyl group and each of R7 and R8 independently denotes a hydrogen atom, a sulfonic acid group, an amino group that may be substituted or —SO2NR9R10, wherein each of R9 and R10 independently denotes a hydrogen atom, an alkyl group, an aryl group or an aralkyl group and may form a heterocycle with a nitrogen atom;
• n denotes an integer between 1 and 3;
• if neither R7 nor R8 is —SO2NR9R10, at least one of said R1 through R4 is an alkylene group, an arylene group or an aralkylene group having —SO2NR9R10 as a substituent;
• and An denotes a counter anion, which is not necessary when a counter anion exists in the molecule.

An ink-jet recording method comprising:

• ejecting a coloring liquid onto a recording medium by means of an ink-jet method;
• wherein said coloring liquid includes at least one colorant compound having a structure represented by the general formula (1) below:
• wherein
• each of R1 through R4 independently denotes a hydrogen atom, an alkyl group that may be substituted, an aryl group that may be substituted or an aralkyl group that may be substituted, each of R5 and R6 independently denotes a hydrogen atom or an alkyl group and each of R7 and R8 independently denotes a hydrogen atom, a sulfonic acid group, an amino group that may be substituted or —SO2NR9R10, wherein each of R9 and R10 independently denotes a hydrogen atom, an alkyl group, an aryl group or an aralkyl group and may form a heterocycle with a nitrogen atom;
• n denotes an integer between 1 and 3;
• if neither R7 nor R8 is —SO2NR9R10, at least one of said R1 through R4 is an alkylene group, an arylene group or an aralkylene group having —SO2NR9R10 as a substituent;
• and An denotes a counter anion, which is not necessary when a counter anion exists in the molecule.