Abstract: An ink composition contains dyes A and B. Dye A has a width at a half height of the largest peak in the absorption spectrum between 380 nm and 780 nm that is 50 nm or less. Dye B has a corresponding width at the half height that is 70 nm or more. Dye A is present in an amount of 40% by mass or more and 90% by mass or less of the total mass of the dyes.

Abstract: An ink composition contains water, at least one surfactant, and a pigment. The pigment has a specific surface area of 10 m2/g or more and 50 m2/g or less as determined by pulsed NMR at 30° C.

Abstract: A recording method is provided that includes a step of making a record on a recording medium using an ink composition containing a colorant, an organic compound, and water to obtain a recording article. The amount (W1) of moisture in the recording article after one second from recording and the amount (W5) of moisture in the recording article after five seconds from recording satisfy the following relational formulas: W1?2.0 [mg/inch2]??(1) 5.0[%]?(W1?W5)×100/W1?30[%]??(2).

Abstract: An ink composition of the invention is an ink composition to be charged in an ink storage container which includes an ink composition-replenishable ink chamber and an ink inlet, and the ink chamber is able to communicate with outside air. The ink composition includes a pigment; an organic compound; and water, and a resolubility index is 0.5 to 10 minutes, the resolubility index indicating a time required for that after the mass of the ink composition is decreased by 50%, the viscosity thereof is returned to an ink viscosity before the mass is decreased by addition of water in an amount equivalent to the decreased mass.

Abstract: An ink composition at least contains a compound A having a hydroxy group and a compound B having an aldehyde group as polyoxyalkylene alkyl ether surfactants. The mass ratio of the compound B to the compound A is 0.5×10?4 to 30×10?4.

Abstract: An ink composition contains dyes A and B. Dye A has a width at a half height of the largest peak in the absorption spectrum between 380 nm and 780 nm that is 50 nm or less. Dye B has a corresponding width at the half height that is 70 nm or more. Dye A is present in an amount of 40% by mass or more and 90% by mass or less of the total mass of the dyes.

Abstract: An ink composition contains water, at least one surfactant, and a pigment. The pigment has a specific surface area of 10 m2/g or more and 50 m2/g or less as determined by pulsed NMR at 30° C.

Abstract: An ink composition contains resin particles, a pigment, glycol ether, and water, wherein the resin particles satisfy the condition defined by Relational Expression (1) 1.0?(?2/?1)?12.5??(1) (where ?1 represents the volume average particle size of the resin particles in a solution containing 20 mass % of the resin particles and 80 mass % of water, and ?2 represents the volume average particle size of the resin particles in a solution containing 90 mass % of the resin particles and 10 mass % of water).

Abstract: There is provided an ink set including at least: a yellow ink; a magenta ink; and a cyan ink, in which the yellow ink includes one or more kinds selected from a group consisting of coloring materials represented by the following Formulae (Y-1) and (Y-2), the magenta ink includes one or more kinds selected from a group consisting of coloring materials represented by the following Formulae (M-1) and (M-2), and the cyan ink includes one or more kinds selected from a group consisting of coloring materials represented by the following Formulae (C-1) and (C-2).

Abstract: An aqueous ink set for ink jet recording includes an aqueous pigment ink containing water and a pigment as a coloring agent and an aqueous dye ink containing water and a dye as a coloring agent, in which the concentration of the divalent metal ions of the pigment ink is 10 ppm or more, and the potassium ion concentration of the dye ink is 50 ppm or less.

Abstract: An ink composition of the invention is an ink composition to be charged in an ink storage container which includes an ink composition-replenishable ink chamber and an ink inlet, and the ink chamber is able to communicate with outside air. The ink composition includes a pigment; an organic compound; and water, and a resolubility index is 0.5 to 10 minutes, the resolubility index indicating a time required for that after the mass of the ink composition is decreased by 50%, the viscosity thereof is returned to an ink viscosity before the mass is decreased by addition of water in an amount equivalent to the decreased mass.

Abstract: There is provided an ink composition, including: a dye (M-2); a dye (Y-1); an alkylene oxide adduct of acetylene glycol having a main chain of 12 or more carbon atoms; acetylene glycol having a main chain of 10 or more carbon atoms; and a polyoxyalkylene alkyl ether, in which the content ratio A of the dye (M-2) and the dye (Y-1) (the dye (M-2):the dye (Y-1)) is 1.25:1 to 4.75:1.

Abstract: There is provided an ink composition, including: a combination of specific dyes, in which the dynamic contact angle of the ink to a silicon wafer is 24° or lower at 100 msec after dropping, and is 9° or lower at 5,100 msec after dropping.

Abstract: An aqueous ink set for ink jet recording includes an aqueous pigment ink containing water and a pigment as a coloring agent and an aqueous dye ink containing water and a dye as a coloring agent, in which the concentration of the divalent metal ions of the pigment ink is 10 ppm or more, and the potassium ion concentration of the dye ink is 50 ppm or less.

Abstract: An ink composition at least contains a compound A having a hydroxy group and a compound B having an aldehyde group as polyoxyalkylene alkyl ether surfactants. The mass ratio of the compound B to the compound A is 0.5×10?4 to 30×10?4.

Abstract: There is provided an ink composition including: a predetermined dye (C-1); a dye (C-2) containing at least one of C.I. Direct Blues 86 and 199; an alkylene oxide adduct of an acetylene glycol having a main chain of 12 or more carbon atoms; an acetylene glycol having a main chain of 10 or more carbon atoms; and a polyoxyalkylene alkyl ether, in which the content ratio A of the dye (C-1) and the dye (C-2) (the dye (C-1):the dye (C-2)) is 7:3 to 9.5:0.5, and the content of the dye (C-1) is 2.0 mass % to 5.0 mass %.

Abstract: An ink composition includes, as dyes, a dye (Bk-1) represented by the formula (Bk-1); and a dye (Bw-1) represented by the formula (Bw-1), in which a content ratio A (dye (Bk-1):dye (Bw-1)) of the dye (Bk-1) and the dye (Bw-1) is 100:18 to 100:40.

Abstract: A liquid accommodating container in which a fiber member and a liquid are accommodated has a fiber ratio of the fiber member is 5% or more to 30% or less, a fiber diameter of the fiber member is 10 ?m or more to 50 ?m or less, a volume average particle diameter (D50) of a pigment included in the liquid satisfies a condition of 50 nm<D50<150 nm.

Abstract: There is provided an ink composition, including: a dye (M-2); a dye (Y-1); an alkylene oxide adduct of acetylene glycol having a main chain of 12 or more carbon atoms; acetylene glycol having a main chain of 10 or more carbon atoms; and a polyoxyalkylene alkyl ether, in which the content ratio A of the dye (M-2) and the dye (Y-1) (the dye (M-2):the dye (Y-1)) is 1.25:1 to 4.75:1.

Abstract: An ink composition includes, as dyes, a dye (Bk-1) represented by the formula (Bk-1); and a dye (Bw-1) represented by the formula (Bw-1), in which a content ratio A (dye (Bk-1):dye (Bw-1)) of the dye (Bk-1) and the dye (Bw-1) is 100:18 to 100:40.