Provided is an ink jet recording method by which even when an ink jet recording apparatus having a small size and high durability is used, excellent sticking recoverability is obtained and a high-quality image suppressed from causing unevenness can be recorded. The ink jet recording method includes recording an image with an ink jet recording apparatus including: a plurality of aqueous inks; a first ink storage portion; a second ink storage portion; a plurality of tubes; a recording head; and a recovery mechanism. The ratio (η.sub.2/η.sub.1) of the viscosity 112 (mPa.Math.s) of the second ink to the viscosity η.sub.1 (mPa.Math.s) of the first ink is 0.7 or more to 1.5 or less, and the first ink contains a first water-soluble organic solvent having a specific dielectric constant of 40.0 or more.

Provided is an ink jet recording method by which even when an ink jet recording apparatus having a small size and high durability is used, excellent sticking recoverability is obtained and a high-quality image suppressed from causing unevenness can be recorded. The ink jet recording method includes recording an image with an ink jet recording apparatus including: a plurality of aqueous inks; a first ink storage portion; a second ink storage portion; a plurality of tubes; a recording head; and a recovery mechanism. The ratio (η.sub.2/η.sub.1) of the viscosity 112 (mPa.Math.s) of the second ink to the viscosity η.sub.1 (mPa.Math.s) of the first ink is 0.7 or more to 1.5 or less, and the first ink contains a first water-soluble organic solvent having a specific dielectric constant of 40.0 or more.

It is an object of the present invention to provide an aqueous ink for ink jet recording capable of recording a yellow image excellent in color developability and light resistance. An aqueous ink for ink jet recording contains a plurality of pigments and a resin dispersant. The plurality of pigments includes C.I. Pigment Yellow 74 and C.I. Pigment Yellow 138. A cumulative 50% particle diameter in volume-based particle size distribution of the C.I. Pigment Yellow 138 is 85 nm or less. A ratio of the cumulative 50% particle diameter in volume-based particle size distribution of the C.I. Pigment Yellow 138 to a cumulative 50% particle diameter in volume-based particle size distribution of the C.I. Pigment Yellow 74 is 0.72 times or less.

It is an object of the present invention to provide an aqueous ink for ink jet recording capable of recording a yellow image excellent in color developability and light resistance. An aqueous ink for ink jet recording contains a plurality of pigments and a resin dispersant. The plurality of pigments includes C.I. Pigment Yellow 74 and C.I. Pigment Yellow 138. A cumulative 50% particle diameter in volume-based particle size distribution of the C.I. Pigment Yellow 138 is 85 nm or less. A ratio of the cumulative 50% particle diameter in volume-based particle size distribution of the C.I. Pigment Yellow 138 to a cumulative 50% particle diameter in volume-based particle size distribution of the C.I. Pigment Yellow 74 is 0.72 times or less.

An ink composition for forming an electron transport layer of a light-emitting device of a display device includes: an electron-transporting compound including a phosphine oxide moiety; and a solvent represented by Formula 1,

(P═O)(OR.sub.1)(OR.sub.2)(OR.sub.3)  Formula 1

wherein, in Formula 1, R.sub.1 to R.sub.3 each, independently from one another, are hydrogen, deuterium, or a C.sub.1-C.sub.30 alkyl group, and at least one of R.sub.1 to R.sub.3 is a C.sub.1-C.sub.30 alkyl group.

An ink composition for forming an electron transport layer of a light-emitting device of a display device includes: an electron-transporting compound including a phosphine oxide moiety; and a solvent represented by Formula 1,

(P═O)(OR.sub.1)(OR.sub.2)(OR.sub.3)  Formula 1

wherein, in Formula 1, R.sub.1 to R.sub.3 each, independently from one another, are hydrogen, deuterium, or a C.sub.1-C.sub.30 alkyl group, and at least one of R.sub.1 to R.sub.3 is a C.sub.1-C.sub.30 alkyl group.

An ink set containing an inkjet ink and a treatment liquid used in combination with the inkjet ink, wherein the inkjet ink contains a pigment, a water-soluble organic solvent, a surfactant and water, the water-soluble organic solvent contains a glycol ether-based organic solvent having a specific structure, the treatment liquid contains a coagulant, the coagulant contains calcium nitrate in an amount of 6.8 to 20.8% by mass relative to the total mass of the treatment liquid, and the amount of compounds contained in the treatment liquid that have three or more hydroxyl groups is not more than 15% by mass relative to the total mass of the treatment liquid.

An ink set containing an inkjet ink and a treatment liquid used in combination with the inkjet ink, wherein the inkjet ink contains a pigment, a water-soluble organic solvent, a surfactant and water, the water-soluble organic solvent contains a glycol ether-based organic solvent having a specific structure, the treatment liquid contains a coagulant, the coagulant contains calcium nitrate in an amount of 6.8 to 20.8% by mass relative to the total mass of the treatment liquid, and the amount of compounds contained in the treatment liquid that have three or more hydroxyl groups is not more than 15% by mass relative to the total mass of the treatment liquid.

An ink composition includes resin particles, one or more surfactants, one or more water-soluble organic solvents, and a glycol ether, where: the surfactants include a fluorosurfactant having a predetermined structure and an HLB value determined by Griffin's method of 11 or less; the water-soluble organic solvents include one or more selected from the group consisting of glycerin, ethylene glycol, diethylene glycol, polyethylene glycol having a weight-average molecular weight of 10,000 or less, 1,3-propanediol, 1,4-butanediol, and diglycerol; and the glycol ether has a predetermined structure and an HLB value determined by Griffin's method of 11 or less.

An ink composition includes resin particles, one or more surfactants, one or more water-soluble organic solvents, and a glycol ether, where: the surfactants include a fluorosurfactant having a predetermined structure and an HLB value determined by Griffin's method of 11 or less; the water-soluble organic solvents include one or more selected from the group consisting of glycerin, ethylene glycol, diethylene glycol, polyethylene glycol having a weight-average molecular weight of 10,000 or less, 1,3-propanediol, 1,4-butanediol, and diglycerol; and the glycol ether has a predetermined structure and an HLB value determined by Griffin's method of 11 or less.