Abstract: A water-in-oil (W/O) emulsion ink which is suitable for use in inkjet printing and superior in ejection performance and storage stability is provided. A polyglycerin fatty acid ester which fatty acid moiety is oleic acid or isostearic acid and which has an HLB value of 7-14, is used as an emulsifier. The polyglycerin fatty acid ester preferably has a glycerin polymerization degree of 4-20 and preferably contains 1-3 fatty acids per one molecule thereof. The polyglycerin fatty acid ester has an organic value of preferably 550-2300 and an inorganic value of preferably 600-2500. Preferably, the emulsion ink comprises 40-99 mass % of the oil phase and 60-1 mass % of the water phase, and comprises 0.5-40 mass % of the polyglycerin fatty acid ester relative to the total amount of the ink. The water phase may contain a dye and optionally a solubilizer such as an amine based surfactant.

Abstract: A non-aqueous pigment ink includes a pigment, a non-aqueous solvent, a non-water-soluble resin and a water-soluble resin, wherein the non-water-soluble resin is an acrylic polymer formed by a copolymer of a monomer mixture containing at least an alkyl(meth)acrylate (A) having a C8 to C18 alkyl group and a monomer (B) having a ?-diketone group or ?-keto acid ester group.

Abstract: A water-in-oil (W/O) emulsion ink having an ejection performance suitable for inkjet printing and superior storage stability at high temperature includes as emulsifiers, a polyglyceryl fatty acid ester (A) having a fatty acid moiety is isostearic acid or oleic acid with an HLB value of 7-14 and a glycerol polymerization degree of not less than 4, at least one nonionic surfactant (B) selected from (B-a) an esterification product of an organic compound with 3-5 hydroxyl groups and a fatty acid having 18 carbon atoms, (B-b) an alkyl glyceryl ether, (B-c) a diterpene alcohol and (B-d) a sucrose fatty acid ester having an HLB value of not more than 13.

Abstract: A water-in-oil (W/O) emulsion ink which is suitable for use in inkjet printing and is superior in ejection performance and storage stability and low in viscosity is provided. A water-in-oil (W/O) emulsion ink which comprises a polyglycerin with a polymerization degree of not less than 3 in a water phase is provided. As an emulsifier, a polyglycerin fatty acid ester with an HLB value of 7-14 in which fatty acid moiety is oleic acid or isostearic acid, or a polyoxyethylene sorbit fatty acid ester is preferably used. The concentration of the polyglycerin in the water phase is preferably 10-70 mass % relative to 100 mass % of the whole water phase. The polymerization degree of the polyglycerin is preferably not less than 4.

Abstract: In an inkjet printing system using an ink which includes a coloring material dispersed in a solvent, it is aimed that printing density is improved by thickening the ink on a printing medium so as to stay the coloring material on the surface of the printing medium. An inkjet printing method is provided, in which printing is performed by ejecting one of first and second inks onto a printing medium, and then successively ejecting the other ink so as to overlay it on the one ink, wherein the first ink includes at least a first organic solvent and an ?,?-unsaturated carbonyl compound, the second ink includes at least a second organic solvent and an organic compound reactive as a nucleophile with the ?,?-unsaturated carbonyl compound, and at least one of the first and second inks includes a coloring material.

Abstract: A water-in-oil (W/O) emulsion ink which is suitable for use in inkjet printing and superior in ejection performance and storage stability is provided. A polyglycerin fatty acid ester which fatty acid moiety is oleic acid or isostearic acid and which has an HLB value of 7-14, is used as an emulsifier. The polyglycerin fatty acid ester preferably has a glycerin polymerization degree of 4-20 and preferably contains 1-3 fatty acids per one molecule thereof. The polyglycerin fatty acid ester has an organic value of preferably 550-2300 and an inorganic value of preferably 600-2500. Preferably, the emulsion ink comprises 40-99 mass % of the oil phase and 60-1 mass % of the water phase, and comprises 0.5-40 mass % of the polyglycerin fatty acid ester relative to the total amount of the ink. The water phase may contain a dye and optionally a solubilizer such as an amine based surfactant.

Abstract: A water-in-oil (W/O) emulsion ink which is suitable for use in inkjet printing and is low in viscosity and superior in storage stability is provided. The ink comprises an oil phase and a water phase emulsified in the oil phase using a nonionic surfactant, in which the water phase contains a salt of at least one metal selected from potassium or calcium. The metal salt is preferably a calcium salt, and particular preferably calcium chloride. The nonionic surfactant is preferably a polyglycerin fatty acid ester, and particularly preferably an esterification product of a polyglycerin and a hydroxy fatty acid. Preferably, the ink comprises 40-99 mass % of the oil phase and 60-1 mass % of the water phase, and contains a polyglycerin fatty acid ester in an amount of 0.5-40 mass % based on the total of the ink.

Abstract: In an inkjet printing system using an ink which comprises a coloring material dispersed in a solvent, it is aimed that printing density is improved by thickening the ink on a printing medium so as to stay the coloring material on the surface of the printing medium. An inkjet printing method is provided, in which printing is performed by ejecting one of first and second inks onto a printing medium, and then successively ejecting the other ink so as to overlay it on the one ink, wherein the first ink comprises at least a first organic solvent and an ?,?-unsaturated carbonyl compound, the second ink comprises at least a second organic solvent and an organic compound reactive as a nucleophile with the ?,?-unsaturated carbonyl compound, and at least one of the first and second inks comprises a coloring material.

Abstract: A water-in-oil (W/O) emulsion ink which is suitable for use in inkjet printing and is low in viscosity and superior in storage stability is provided. The ink comprises an oil phase and a water phase emulsified in the oil phase using a nonionic surfactant, in which the water phase contains a salt of at least one metal selected from potassium or calcium. The metal salt is preferably a calcium salt, and particular preferably calcium chloride. The nonionic surfactant is preferably a polyglycerin fatty acid ester, and particularly preferably an esterification product of a polyglycerin and a hydroxy fatty acid. Preferably, the ink comprises 40-99 mass % of the oil phase and 60-1 mass % of the water phase, and contains a polyglycerin fatty acid ester in an amount of 0.5-40 mass % based on the total of the ink.