The present invention relates to a water-based ink containing at least pigment-containing water-insoluble crosslinked polymer particles (A), a polymer emulsion (B) and water, in which a water-insoluble crosslinked polymer constituting the crosslinked polymer particles (A) is obtained by subjecting a polymer that contains a constitutional unit derived from a carboxylic acid monomer having an acid value of not less than 200 mgKOH/g and a constitutional unit derived from a hydrophobic monomer, to crosslinking reaction with an epoxy compound, and a polymer constituting the polymer emulsion (B) contains a constitutional unit derived from a carboxylic acid monomer and a constitutional unit derived from a hydrophobic monomer. The water-based ink of the present invention is excellent in ejection stability and fastness of the printed characters or images while maintaining good optical density.

There is provided a radiation curable ink jet composition including: a monomer A that has one of a (meth)acryloyloxy group and a (meth)acryloyl group and has a cyclic structure containing one or more nitrogen atoms and one or more oxygen atoms in addition to the (meth)acryloyloxy group and the (meth)acryloyl group; and a monofunctional monomer B other than the monomer A; in which the content of the monomer A is equal to or less than 25% by mass with respect to the total mass of the composition, and in which mol average Tg of the monomer A and the monofunctional monomer B is equal to or greater than 45° C.

There is provided a radiation curable ink jet composition including: a monomer A that has one of a (meth)acryloyloxy group and a (meth)acryloyl group and has a cyclic structure containing one or more nitrogen atoms and one or more oxygen atoms in addition to the (meth)acryloyloxy group and the (meth)acryloyl group; and a monofunctional monomer B other than the monomer A; in which the content of the monomer A is equal to or less than 25% by mass with respect to the total mass of the composition, and in which mol average Tg of the monomer A and the monofunctional monomer B is equal to or greater than 45° C.

Provided is an inkjet pigment ink which contains a pigment that is selected from the group consisting of C.L. Pigment Yellow 74 having a transmittance of 70% or more, C.I. Pigment Red 269 having a transmittance of 70% or more, C.I. Pigment Red 122 having a transmittance of less than 70% and C.I. Pigment Yellow 150; a water-soluble solvent that is selected from the group consisting of glycol ethers and diols; water; and a pigment dispersing resin that is a copolymer which contains a monomer A, a monomer B and a monomer C as unit components. The monomer A is an alkyl (meth)acrylate ester; the monomer B is styrene, α-methyl styrene or benzyl (meth)acrylate; and the monomer C is (meth)acrylic acid.

Provided is an inkjet pigment ink which contains a pigment that is selected from the group consisting of C.L. Pigment Yellow 74 having a transmittance of 70% or more, C.I. Pigment Red 269 having a transmittance of 70% or more, C.I. Pigment Red 122 having a transmittance of less than 70% and C.I. Pigment Yellow 150; a water-soluble solvent that is selected from the group consisting of glycol ethers and diols; water; and a pigment dispersing resin that is a copolymer which contains a monomer A, a monomer B and a monomer C as unit components. The monomer A is an alkyl (meth)acrylate ester; the monomer B is styrene, α-methyl styrene or benzyl (meth)acrylate; and the monomer C is (meth)acrylic acid.

The present disclosure provides a polyetheramine produced from a cyclic amide initiator which is first alkoxylated and then reductively aminated to form the polyetheramine. The polyetheramine of the present disclosure may be used in a variety of applications, such as a raw material in the synthesis of a dispersant for use in an aqueous pigment dispersion or as a fuel additive in a hydrocarbon fuel composition.

The present disclosure provides a polyetheramine produced from a cyclic amide initiator which is first alkoxylated and then reductively aminated to form the polyetheramine. The polyetheramine of the present disclosure may be used in a variety of applications, such as a raw material in the synthesis of a dispersant for use in an aqueous pigment dispersion or as a fuel additive in a hydrocarbon fuel composition.

The present invention provides a pigment dispersant that exhibits high fine dispersibility, stability, and fluidity in a small amount, a pigment dispersion liquid including the pigment dispersant, and a process of producing the pigment dispersant and pigment dispersion liquid. The pigment dispersant contains as a main component, a graft copolymer formed through living radical polymerization using two or more monomers containing including a methacrylate A having an acidic group or a basic group and a methacrylate-based macromonomer B having a methacrylate residue at one terminal of a particular polymer chain that has a molecular weight of from 500 to 5000. A ratio of a total molar number of the methacrylate-based monomers relative to 1 mol of a polymerization-initiating compound in the raw material monomers is from 20 to 50 mol. A ratio of the B component-derived polymer chain to the graft copolymer is from 50 to 90 mass %.

The present invention provides a pigment dispersant that exhibits high fine dispersibility, stability, and fluidity in a small amount, a pigment dispersion liquid including the pigment dispersant, and a process of producing the pigment dispersant and pigment dispersion liquid. The pigment dispersant contains as a main component, a graft copolymer formed through living radical polymerization using two or more monomers containing including a methacrylate A having an acidic group or a basic group and a methacrylate-based macromonomer B having a methacrylate residue at one terminal of a particular polymer chain that has a molecular weight of from 500 to 5000. A ratio of a total molar number of the methacrylate-based monomers relative to 1 mol of a polymerization-initiating compound in the raw material monomers is from 20 to 50 mol. A ratio of the B component-derived polymer chain to the graft copolymer is from 50 to 90 mass %.

An oil-based inkjet ink is disclosed, that contains a pigment, a fatty acid ester-based solvent (A) having a viscosity of 5.0 mPa.Math.s or lower and a boiling point of 300° C. or higher but lower than 400° C., and a fatty acid ester-based solvent (B) having a viscosity of 10.0 mPa.Math.s or higher and a boiling point of 400° C. or higher.