The problem to be solved by the present invention is to provide an ink set that enables forming a printed article with reduced bleeding and color mixing. The present invention is an ink set that includes a black pigment ink (a) having a static surface tension (a1) of 20 mN/m to 40 mN/m and at least one pigment ink (b) selected from the group consisting of a magenta pigment ink and a yellow pigment ink. The static surface tension of the pigment ink (b) is smaller than static surface tension (a1) by 0.1 mN/m to 0.7 mN/m.

The problem to be solved by the present invention is to provide an ink set that enables forming a printed article with reduced bleeding and color mixing. The present invention is an ink set that includes a black pigment ink (a) having a static surface tension (a1) of 20 mN/m to 40 mN/m and at least one pigment ink (b) selected from the group consisting of a magenta pigment ink and a yellow pigment ink. The static surface tension of the pigment ink (b) is smaller than static surface tension (a1) by 0.1 mN/m to 0.7 mN/m.

A curable composition containing: a methylene malonate compound; a 2-cyanoacrylate compound; and a Lewis acidic compound. The methylene malonate compound is preferably a compound represented by formula (1) or formula (2). In the formulae (1) and (2), X.sup.1 to X.sup.4 each independently represent O, NR, or C(R).sub.2, R's each independently represent a hydrogen atom, an alkyl group, or an aryl group, R.sup.1 and R.sup.2 each independently represent an alkyl group or an aryl group, and R.sup.3 represents an alkylene group, an arylene group, or a group obtained by combining two or more of these groups.

##STR00001##

A curable composition containing: a methylene malonate compound; a 2-cyanoacrylate compound; and a Lewis acidic compound. The methylene malonate compound is preferably a compound represented by formula (1) or formula (2). In the formulae (1) and (2), X.sup.1 to X.sup.4 each independently represent O, NR, or C(R).sub.2, R's each independently represent a hydrogen atom, an alkyl group, or an aryl group, R.sup.1 and R.sup.2 each independently represent an alkyl group or an aryl group, and R.sup.3 represents an alkylene group, an arylene group, or a group obtained by combining two or more of these groups.

##STR00001##

An ink composition including water, a pigment, a pigment dispersion polymer A, and a water-soluble polymer B different from the pigment dispersion polymer A, in which the water-soluble polymer B contains a specific acid group and a constitutional unit represented by Formula (1), an ink set, and an image recording method. R.sup.1, R.sup.11, Y.sup.1, and Y.sup.2 each independently represent a hydrogen atom or a monovalent substituent, and L.sup.1 and L.sup.2 each independently represent a divalent linking group or a single bond. Y.sup.1 and Y.sup.2 may be bonded to each other to form a nitrogen-containing heterocycle with L.sup.1, L.sup.2, and N.

##STR00001##

An ink composition including water, a pigment, a pigment dispersion polymer A, and a water-soluble polymer B different from the pigment dispersion polymer A, in which the water-soluble polymer B contains a specific acid group and a constitutional unit represented by Formula (1), an ink set, and an image recording method. R.sup.1, R.sup.11, Y.sup.1, and Y.sup.2 each independently represent a hydrogen atom or a monovalent substituent, and L.sup.1 and L.sup.2 each independently represent a divalent linking group or a single bond. Y.sup.1 and Y.sup.2 may be bonded to each other to form a nitrogen-containing heterocycle with L.sup.1, L.sup.2, and N.

##STR00001##

An erasable ink set includes: an erasable ink; and an erasing time adjuster which is stored separately from the erasable ink and is capable of adjusting an erasing time of the erasable ink. The erasable ink includes a color developing agent including a pH indicator, water, and at least one selected from the group consisting of a first water-soluble organic solvent and a first surfactant. The erasing time adjuster includes water and at least one selected from the group consisting of a second water-soluble organic solvent and a second surfactant.

An aqueous composition can be used for pre-treating a substrate prior to inkjet printing to provide a white opaque background for inkjet-printed images. This aqueous composition includes: (a) one or more water-soluble salts of a multivalent metal cation at 5-30 weight %; (b) a nonionic or cationic water-soluble or water-dispersible polymeric binder material at 5-30 weight %; and (c) surface-treated visible light-scattering particles having a D.sub.50 (median) particle size of at least 0.04 μm and up to and including 2 μm in an amount of 5-60 weight % based on the total aqueous composition weight. The pre-treated substrate is useful as an inkjet receiving medium that can be readily inkjet-printed particularly with anionically-stabilized aqueous pigment-based inks.

An ink jet ink composition includes: an acetoacetanilide-based monoazo pigment coated with a water-insoluble polymer; 1-(2-hydroxyethyl)-2-pyrrolidone; and water.

An ink jet ink composition includes: an acetoacetanilide-based monoazo pigment coated with a water-insoluble polymer; 1-(2-hydroxyethyl)-2-pyrrolidone; and water.