Ink, and ink-jet recording method and apparatus employing the ink

In an ink-jet recording method in which recording is conducted by ejecting droplets of an ink through an orifice onto a recording medium in response to a recording signal, the improvement comprising employing as the ink a composition comprising a recording agent represented by the general formula ##STR14## where R.sup.1 is a radical selected from the group of lower alkyl, lower alkoxy, --COOM, and --SO.sub.3 M;

• R.sup.2 and R.sup.3 are respectively a radical selected from the group of hydrogen, lower alkyl, lower alkoxy, amino, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• R.sup.4 and R.sup.5 are respectively a radical selected from the group of lower alkyl, lower alkoxy, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• A is ##STR15## R.sup.6 is a radical selected from the group of acetyl, benzoyl, --SO2C6H5, --SO2C6H4--CH3, phenyl, which is unsubstituted or substituted by --COOM or methyl, and ##STR16## R.sup.7 and R.sup.8 are respectively a radical selected from the group of hydrogen, hydroxyl, and --C.sub.2 H.sub.4 OH;
• R.sup.9 and R.sup.10 are respectively a radical selected from the group of hydrogen, amino, hydroxyl and lower alkoxy;
• n is 1 or 2;
• m is 0 or 1;
• and M is an alkali metal or ammonium.

A recording unit having an ink container portion for holding an ink and a head portion for ejecting the ink in droplets, the ink comprising a recording agent represented by the general formula ##STR17## where R.sup.1 is a radical selected from the group of lower alkyl, lower alkoxy, --COOM, and --SO.sub.3 M;

• R.sup.2 and R.sup.3 are respectively a radical selected from the group of hydrogen, lower alkyl, lower alkoxy, amino, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• R.sup.4 and R.sup.5 are respectively a radical selected from the group of lower alkyl, lower alkoxy, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• A is ##STR18## R.sup.6 is a radical selected from the group of acetyl, benzoyl, --SO.sub.2 C.sub.6 H.sub.5, --SO.sub.2 C.sub.6 H.sub.4 --CH.sub.3, phenyl, which is unsubstituted or substituted by --COOM or methyl, and ##STR19## R.sup.7 and R.sup.8 are respectively a radical selected from the group of hydrogen, hydroxyl, and --C.sub.2 H.sub.4 OH;
• R.sup.9 and R.sup.10 are respectively a radical selected from the group of hydrogen, amino, hydroxyl and lower alkoxy;
• n is 1 or 2;
• m is 0 or 1;
• and M is an alkali metal or ammonium.

An ink cartridge having an ink container portion for holding an ink, the ink comprising a recording agent represented by the general formula ##STR20## where R.sup.1 is a radical selected from the group of lower alkyl, lower alkoxy, --COOM, and --SO.sub.3 M;

• R.sup.2 and R.sup.3 are respectively a radical selected from the group of hydrogen, lower alkyl, lower alkoxy, amino, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• R.sup.4 and R.sup.5 are respectively a radical selected from the group of lower alkyl, lower alkoxy, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• A is ##STR21## R.sup.6 is a radical selected from the group of acetyl, benzoyl, --SO.sub.2 C.sub.6 H.sub.5, --SO.sub.2 C.sub.6 H.sub.4 --CH.sub.3, phenyl, which is unsubstituted or substituted by --COOM or methyl, and ##STR22## R.sup.7 and R.sup.8 are respectively a radical selected from the group of hydrogen, hydroxyl, and --C.sub.2 H.sub.4 OH;
• R.sup.9 and R.sup.10 are respectively a radical selected from the group of hydrogen, amino, hydroxyl and lower alkoxy;
• n is 1 or 2;
• m is 0 or 1;
• and M is an alkali metal or ammonium.

An ink-jet recording apparatus having an ink container portion for holding an ink and a head portion for ejecting the ink in droplets, the ink comprising a recording agent represented by the general formula ##STR23## where R.sup.1 is a radical selected from the group of lower alkyl, lower alkoxy, --COOM, and --SO.sub.3 M;

• R.sup.2 and R.sup.3 are respectively a radical selected from the group of hydrogen, lower alkyl, lower alkoxy, amino, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• R.sup.4 and R.sup.5 are respectively a radical selected from the group of lower alkyl, lower alkoxy, --NHCOCH3, --SO3M, and COOM;
• A is ##STR24## R.sup.6 is a radical selected from the group of acetyl, benzoyl, --SO.sub.2 C.sub.6 H.sub.5, --SO.sub.2 C.sub.6 H.sub.4 --CH.sub.3, phenyl, which is unsubstituted or substituted by --COOM or methyl, and ##STR25## R.sup.7 and R.sup.8 are respectively a radical selected from the group of hydrogen, hydroxyl, and --C.sub.2 H.sub.4 OH;
• R.sup.9 and R.sup.10 are respectively a radical selected from the group of hydrogen, amino, hydroxyl and lower alkoxy;
• n is 1 or 2;
• m is 0 or 1;
• and M is an alkali metal or ammonium.

An ink-jet recording apparatus having a head portion for ejecting an ink in droplets, an inkcartridge having an ink container portion for holding the ink, and an ink-supplying portion for supplying the ink from the ink cartridge to the recording head, the ink comprising a recording agent represented by the general formula ##STR26## where R.sup.1 is a radical selected from the group of lower alkyl, lower alkoxy, --COOM, and --SO.sub.3 M;

• R.sup.2 and R.sup.3 are respectively a radical selected from the group of hydrogen, lower alkyl, lower alkoxy, amino, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• R.sup.4 and R.sup.5 are respectively a radical selected from the group of lower alkyl, lower alkoxy, --NHCOCH.sub.3, --SO.sub.3 M, and COOM;
• A is ##STR27## R.sup.6 is a radical selected from the group of acetyl, benzoyl, --SO.sub.2 C.sub.6 H.sub.5, --SO.sub.2 C.sub.6 H.sub.4 --CH.sub.3, phenyl, which is unsubstituted or substituted by --COOM or methyl, and ##STR28## R.sup.7 and R.sup.8 are respectively a radical selected from the group of hydrogen, hydroxyl, and --C.sub.2 H.sub.4 OH;
• R.sup.9 and R.sup.10 are respectively a radical selected from the group of hydrogen, amino, hydroxyl and lower alkoxy;
• n is 1 or 2;
• m is 0 or 1;
• and M is an alkali metal or ammonium.