Abstract: Provided is an ink jet ink capable of recording an image having an unprecedentedly high level of scratch resistance and excellent glossiness while satisfying reliability of the ink such as ejection stability. The ink jet ink contains at least a pigment and a graft polymer, and is characterized in that the graft polymer includes at least a specific nonionic unit and a unit having a polysiloxane structure.

Abstract: The invention provides provide an ink jet ink exhibiting such an excellent ejection property that when an ink containing a polymer capable of improving the scratch resistance of a recorded article is used, the deviation of the ink-droplet impact point on a recording medium is prevented. The ink jet ink contains a polymer and a surfactant, wherein the acid value of the polymer is from 100 mg KOH/g or more to 220 mg KOH/g or less, the weight-average molecular weight of the polymer is from 3,000 or more to 10,000 or less, and the surfactant has a structure represented by the following formula (1) wherein n is a numerical value of from 3 or more to 27 or less, and m is a numerical value of from 16 or more to 31 or less.

Abstract: An object of the present invention is to provide an ink jet recording method which gives an ink excellent anti-sticking properties and can suppress the occurrence of undertrapping when recording surfaces of recording media which each have an ink-receiving layer are overlapped with each other, and to provide an ink jet recording apparatus. The ink jet recording method of forming an image on the recording medium having the ink-receiving layer by ejecting an ink from an ink jet recording head, the method including performing at least one of drying the recording medium which has the image formed thereon and humidifying a gap between the recording head and the recording medium, wherein the ink to be used for forming the image is an ink which contains water, a water-soluble organic solvent and a specific compound.

Abstract: An object of the invention is to provide an ink set which enables to improve image density and scratch resistance of the images recorded using an ink containing a self-dispersion pigment and an ink containing a modified siloxane compound. An ink set to be used for ink jet recording including plural inks having a first ink and a second ink independently, wherein the first ink contains at least a pigment having functional groups on surface of pigment particles and a compound having adsorptivity to the pigment and the functional group density on the surface of the pigment particles is 1.5 ?mol/m2 or more and less than 2.6 ?mol/m2 and the second ink contains at least a pigment and a modified siloxane compound.

Abstract: Provided are an ink jet ink set, an ink jet recording method, and an ink jet recording apparatus each of which can reduce the graininess of an image to be recorded and improve the water fastness of the image even in a recording medium such as plain paper. The ink jet ink set has a first ink and a second ink independently, and is used so that the first and second inks overlap each other at least partly upon application of the inks to a recording medium. The first ink contains at least a pigment and a silicone oil. The second ink contains at least a pigment and a graft polymer that includes at least a nonionic unit represented by the general formula (I) and a unit having a polysiloxane structure.

Abstract: An object of the present invention is to provide an ink jet recording method which gives an ink excellent anti-sticking properties and can suppress the occurrence of undertrapping when recording surfaces of recording media which each have an ink-receiving layer are overlapped with each other, and to provide an ink jet recording apparatus. The ink jet recording method of forming an image on the recording medium having the ink-receiving layer by ejecting an ink from an ink jet recording head, the method including performing at least one of drying the recording medium which has the image formed thereon and humidifying a gap between the recording head and the recording medium, wherein the ink to be used for forming the image is an ink which contains water, a water-soluble organic solvent and a specific compound.

Abstract: A pigment ink is provided which has good ink reliability and storage stability and can achieve superior scratch resistance of images at such a level that coloring materials are hardly scraped off even when images are scratched with finger nails under application of such strong pressure as to scratch a recording medium at its non-recorded areas. The pigment ink contains a pigment, a modified siloxane compound having a specific structure, and a polymer whose acid value and hydrogen bond parameter (?h) are specified.

Abstract: An object of the invention is to provide an ink set which enables to improve image density and scratch resistance of the images recorded using an ink containing a self-dispersion pigment and an ink containing a modified siloxane compound. An ink set to be used for ink jet recording including plural inks having a first ink and a second ink independently, wherein the first ink contains at least a pigment having functional groups on surface of pigment particles and a compound having adsorptivity to the pigment and the functional group density on the surface of the pigment particles is 1.5 ?mol/m2 or more and less than 2.6 ?mol/m2 and the second ink contains at least a pigment and a modified siloxane compound.

Abstract: Provided are an ink jet ink set, an ink jet recording method, and an ink jet recording apparatus each of which can reduce the graininess of an image to be recorded and improve the water fastness of the image even in a recording medium such as plain paper. The ink jet ink set has a first ink and a second ink independently, and is used so that the first and second inks overlap each other at least partly upon application of the inks to a recording medium. The first ink contains at least a pigment and a silicone oil. The second ink contains at least a pigment and a graft polymer that includes at least a nonionic unit represented by the general formula (I) and a unit having a polysiloxane structure.

Abstract: Provided is an ink jet ink capable of recording an image having an unprecedentedly high level of scratch resistance and excellent glossiness while satisfying reliability of the ink such as ejection stability. The ink jet ink contains at least a pigment and a graft polymer, and is characterized in that the graft polymer includes at least a specific nonionic unit and a unit having a polysiloxane structure.

Abstract: The invention provides provide an ink jet ink exhibiting such an excellent ejection property that when an ink containing a polymer capable of improving the scratch resistance of a recorded article is used, the deviation of the ink-droplet impact point on a recording medium is prevented. The ink jet ink contains a polymer and a surfactant, wherein the acid value of the polymer is from 100 mg KOH/g or more to 220 mg KOH/g or less, the weight-average molecular weight of the polymer is from 3,000 or more to 10,000 or less, and the surfactant has a structure represented by the following formula (1) wherein n is a numerical value of from 3 or more to 27 or less, and m is a numerical value of from 16 or more to 31 or less.

Abstract: A pigment ink is provided which has good ink reliability and storage stability and can achieve superior scratch resistance of images at such a level that coloring materials are hardly scraped off even when images are scratched with finger nails under application of such strong pressure as to scratch a recording medium at its non-recorded areas. The pigment ink contains a pigment, a modified siloxane compound having a specific structure, and a polymer whose acid value and hydrogen bond parameter (?h) are specified.