An aqueous polyurethane resin dispersion, the polyurethane resin is obtainable by reacting an allophanate based isocyanate according to general formula I or II, optionally a polyether diol, a polyol containing a quaternary N-atom or tertiary amino group and a polyol selected from the group consisting of polyester polyol, polyether polyol, polycarbonate polyol, a polyacrylate polyol, a polyolefin and a polyamide polyol. The polyurethane resin is suitable as a resin in treatment liquids of substrates and images made by inkjet printing.

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An ink set includes a non-white ink and a white ink. The non-white ink contains water, a coloring material, an organic solvent, and an acetylene glycol compound. The white ink contains water, a coloring material, an organic solvent, and a compound represented by General formula (1) below

##STR00001##

where R represents a hydrogen atom or a methyl group, n.sub.1 and n.sub.2 represent integers of from 1 through 7, k represents an integer of from 0 through 5, and m represents an integer of from 1 through 20.

An ink set includes a non-white ink and a white ink. The non-white ink contains water, a coloring material, an organic solvent, and an acetylene glycol compound. The white ink contains water, a coloring material, an organic solvent, and a compound represented by General formula (1) below

##STR00001##

where R represents a hydrogen atom or a methyl group, n.sub.1 and n.sub.2 represent integers of from 1 through 7, k represents an integer of from 0 through 5, and m represents an integer of from 1 through 20.

A treatment liquid composition according to the present disclosure includes a polyamide epihalohydrin polymer, and a quaternary ammonium salt polymer other than the polyamide epihalohydrin polymer.

An image forming method includes a processing fluid applying step and an ink applying step. The processing fluid applying step involves applying a processing fluid containing a multivalent metal salt, a resin T.sub.A, a resin T.sub.B different from the resin T.sub.A, and a silicone-based surfactant to a non-permeating base material by an inkjet method, where the processing fluid is free of an organic solvent having a boiling point of 200° C. or higher at normal pressure. The ink applying step involves applying an ink containing a coloring material, an organic solvent, and a resin onto the processing fluid.

An ink set has two or more aqueous pigment-based inks, each of which has 75-95 weight %, a) one or more pigment colorants, and b) one or more water-miscible humectants that are present in a total amount of at least 1 weight % and up to and including 20 weight %, and consist essentially of compounds, each of which has a carbon atom to oxygen atom ratio of at least 1.0:1.0 and only two hydroxy groups. The weight % amounts of water and the b) water-miscible humectants are based on the total weight of each aqueous pigment-based ink. The aqueous pigment-based inks in the ink set can be used individual or in combination to provide monochrome or polychrome inkjet-printed images on various ink-receptive media and using various inkjet printing equipment and methods.

An ink set has two or more aqueous pigment-based inks, each of which has 75-95 weight %, a) one or more pigment colorants, and b) one or more water-miscible humectants that are present in a total amount of at least 1 weight % and up to and including 20 weight %, and consist essentially of compounds, each of which has a carbon atom to oxygen atom ratio of at least 1.0:1.0 and only two hydroxy groups. The weight % amounts of water and the b) water-miscible humectants are based on the total weight of each aqueous pigment-based ink. The aqueous pigment-based inks in the ink set can be used individual or in combination to provide monochrome or polychrome inkjet-printed images on various ink-receptive media and using various inkjet printing equipment and methods.

An ink set is an ink set including a cyan ink C1 which has a fluorescent brightening intensity of 3.0 or greater and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a magenta ink M1 which has a fluorescent brightening intensity of 3.0 or greater and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a yellow ink Y1 which has a fluorescent brightening intensity of 3.0 or greater and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a cyan ink C2 which has a fluorescent brightening intensity of less than 3.0 and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a magenta ink M2 which has a fluorescent brightening intensity of less than 3.0 and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, and a yellow ink Y2 which has a fluorescent brightening intensity of less than 3.0 and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, in which the SP values are values obtained by a turbidity titration method using a mixed solution of water and acetone.

An ink set is an ink set including a cyan ink C1 which has a fluorescent brightening intensity of 3.0 or greater and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a magenta ink M1 which has a fluorescent brightening intensity of 3.0 or greater and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a yellow ink Y1 which has a fluorescent brightening intensity of 3.0 or greater and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a cyan ink C2 which has a fluorescent brightening intensity of less than 3.0 and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, a magenta ink M2 which has a fluorescent brightening intensity of less than 3.0 and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, and a yellow ink Y2 which has a fluorescent brightening intensity of less than 3.0 and an SP value of 12 to 18 (cal/cm.sup.3).sup.1/2, in which the SP values are values obtained by a turbidity titration method using a mixed solution of water and acetone.

Provided are pre-coat formulations, ink formulations, ink systems and printing methods for patterning a surface with a desired pattern.