An ink composition includes colorant, co-solvent system, acid (e.g., oleic, linoleic, undecanoic, dodecanoic, and/or tridecanoic acids), lithium, polymer as binder, and water. The co-solvent system is selected from i) from 9 to 25 wt % of sulfolane with no other co-solvent, ii) hydroxylated co-solvent, from 4 to 16 wt % of sulfolane, and at least 8 wt % of another non-hy-droxylated co-solvent; iii) hydroxylated co-solvent, from 7 to 16 wt % of sulfolane, and at least 3 wt % of the other non-hydroxylated co-solvent; and iv) a hydroxylated co-solvent and from 9 wt % to 16 wt % of sulfolane. When i) or ii) or iv) is used, at least 0.15 wt % acid and at least 200 ppm lithium are included; or when iii) is used, at least 0.25 wt % acid and at least 100 ppm lithium are included; or when iii) is used, at least 0.15 wt % acid and at least 150 ppm lithium are included.

An ink composition includes colorant, co-solvent system, acid (e.g., oleic, linoleic, undecanoic, dodecanoic, and/or tridecanoic acids), lithium, polymer as binder, and water. The co-solvent system is selected from i) from 9 to 25 wt % of sulfolane with no other co-solvent, ii) hydroxylated co-solvent, from 4 to 16 wt % of sulfolane, and at least 8 wt % of another non-hy-droxylated co-solvent; iii) hydroxylated co-solvent, from 7 to 16 wt % of sulfolane, and at least 3 wt % of the other non-hydroxylated co-solvent; and iv) a hydroxylated co-solvent and from 9 wt % to 16 wt % of sulfolane. When i) or ii) or iv) is used, at least 0.15 wt % acid and at least 200 ppm lithium are included; or when iii) is used, at least 0.25 wt % acid and at least 100 ppm lithium are included; or when iii) is used, at least 0.15 wt % acid and at least 150 ppm lithium are included.

A water-based ink for ink-jet recording includes: a self-dispersible pigment having an anionic group; water; a water-soluble resin; and an anionic surfactant, wherein the water-soluble resin is an ABA-type triblock copolymer which has a polymer block A composed only of methyl methacrylate and methacrylic acid and a polymer block B composed only of benzyl methacrylate and methacrylic acid; which has a weight average molecular weight of 3,000 to 30,000; which has an acid value of 90 mgKOH/g to 200 mgKOH/g; and which is partially or completely neutralized.

A water-based ink for ink-jet recording includes: a self-dispersible pigment having an anionic group; water; a water-soluble resin; and an anionic surfactant, wherein the water-soluble resin is an ABA-type triblock copolymer which has a polymer block A composed only of methyl methacrylate and methacrylic acid and a polymer block B composed only of benzyl methacrylate and methacrylic acid; which has a weight average molecular weight of 3,000 to 30,000; which has an acid value of 90 mgKOH/g to 200 mgKOH/g; and which is partially or completely neutralized.

Provided is an ink set enabling the recording of images that have excellent color developability and bronzing resistance and have suppressed a coloring by fringe when a clear ink and a pigment ink are used in combination. An aqueous ink set includes a combination of a first ink containing no coloring material and a second ink containing a coloring material.

Provided is an ink set enabling the recording of images that have excellent color developability and bronzing resistance and have suppressed a coloring by fringe when a clear ink and a pigment ink are used in combination. An aqueous ink set includes a combination of a first ink containing no coloring material and a second ink containing a coloring material.

An ink composition adapted to be poured into an ink container including an ink chamber, the ink chamber partitioned by a wall, refillable with the ink composition via an ink poring port, and communicating with external air, the ink composition comprising a pigment, a resin and an organic solvent, wherein the ink composition has a static contact angle of 10 or more to a member constituting an inner side of the wall.

An ink composition adapted to be poured into an ink container including an ink chamber, the ink chamber partitioned by a wall, refillable with the ink composition via an ink poring port, and communicating with external air, the ink composition comprising a pigment, a resin and an organic solvent, wherein the ink composition has a static contact angle of 10 or more to a member constituting an inner side of the wall.

A solvent-based ink jet ink composition accommodating body includes a solvent-based ink jet ink composition which includes a solvent that is a compound represented by a general formula (1) below, and for which a moisture absorption rate is 2 (mass %.Math.24 hours) or more at 40 C. and a relative humidity of 100% RH; and a container in which the solvent-based ink jet ink composition is accommodated, in which the container is either of at least a container formed of a member having an inorganic oxide layer or a package which accommodates the container in which the solvent-based ink jet ink composition is accommodated and is formed of a member having an inorganic oxide layer.

R.sup.1O(R.sup.2O).sub.mR.sup.3 (1)

(In general formula (1), R.sup.1 and R.sup.3 each independently represent hydrogen or an alkyl group having 1 to 5 carbon atoms. Herein, either of at least R.sup.1 or R.sup.3 is an alkyl group having 1 to 5 carbon atoms. R.sup.2 represents an alkylene group having 2 to 4 carbon atoms. m represents an integer of 1 to 6.)

A solvent-based ink jet ink composition accommodating body includes a solvent-based ink jet ink composition which includes a solvent that is a compound represented by a general formula (1) below, and for which a moisture absorption rate is 2 (mass %.Math.24 hours) or more at 40 C. and a relative humidity of 100% RH; and a container in which the solvent-based ink jet ink composition is accommodated, in which the container is either of at least a container formed of a member having an inorganic oxide layer or a package which accommodates the container in which the solvent-based ink jet ink composition is accommodated and is formed of a member having an inorganic oxide layer.

R.sup.1O(R.sup.2O).sub.mR.sup.3 (1)

(In general formula (1), R.sup.1 and R.sup.3 each independently represent hydrogen or an alkyl group having 1 to 5 carbon atoms. Herein, either of at least R.sup.1 or R.sup.3 is an alkyl group having 1 to 5 carbon atoms. R.sup.2 represents an alkylene group having 2 to 4 carbon atoms. m represents an integer of 1 to 6.)