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 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.

##STR00001##

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.

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.

The present invention provides a reversibly thermochromic aqueous inkjet printer ink composition which can form print images of high resolution and rich color development. The composition comprises: a reversibly thermochromic microcapsule pigment, water, and a polyalcohol organic solvent. Microcapsules which are comprised in the composition have a volume-based mean particle size (X) of 0.1 to 2 μm and a mean cross-sectional membrane thickness (Y) of 0.02 to 0.4 which is average of cross-sectional membrane thickness defined by the formula:

cross-sectional membrane thickness=(outer section diameter−inner section diameter)/2.

The present invention provides a reversibly thermochromic aqueous inkjet printer ink composition which can form print images of high resolution and rich color development. The composition comprises: a reversibly thermochromic microcapsule pigment, water, and a polyalcohol organic solvent. Microcapsules which are comprised in the composition have a volume-based mean particle size (X) of 0.1 to 2 μm and a mean cross-sectional membrane thickness (Y) of 0.02 to 0.4 which is average of cross-sectional membrane thickness defined by the formula:

cross-sectional membrane thickness=(outer section diameter−inner section diameter)/2.

A printing formulation, an electronic device comprising a function layer prepared from the printing formulation and a preparation method for obtaining a functional material thin film by utilizing the printing formulation. The printing formulation comprises at least one functional material and at least one inorganic ester solvent, and the inorganic ester solvent can be selected from alkyl borate or alkyl phosphate.

A printing formulation, an electronic device comprising a function layer prepared from the printing formulation and a preparation method for obtaining a functional material thin film by utilizing the printing formulation. The printing formulation comprises at least one functional material and at least one inorganic ester solvent, and the inorganic ester solvent can be selected from alkyl borate or alkyl phosphate.