Abstract: An ink set containing a water-based ink for ink jet recording and a treatment liquid. The water-based ink contains a phosphate group-modified self-dispersing pigment, water, and a water-soluble organic solvent. The treatment liquid contains a monovalent metal ion, water, and a water-soluble organic solvent.

Abstract: An evaluation method for evaluating a pigment ink for ink-jet recording used together with a dye ink and containing a pigment and water includes an aggregation property evaluation method for the pigment in which 10 parts by weight of an aqueous sodium chloride solution is added to 100 parts by weight of the pigment ink; the evaluation method including first aggregation property evaluation adding an X wt % aqueous sodium chloride solution; and second aggregation property evaluation adding a Y wt % aqueous sodium chloride solution; wherein concentrations of the aqueous sodium chloride solutions are set to fulfill the following condition in the first and second aggregation property evaluations: 1.0?X<Y?2.5. The optical density of a printed matter and the dispersion stability of the pigment when the pigment ink is brought in contact with the dye ink can be easily evaluated before the printing.

Abstract: An ink set containing a water-based ink for ink jet recording and a treatment liquid. The water-based ink contains a phosphate-group modified self-dispersing pigment, water, and a water-soluble organic solvent. The treatment liquid contains an aggregating agent, water, and a water-soluble organic solvent. A dynamic surface tension of the water-based ink, measured under the condition where a life time is about 50 ms, is in the range of 35 mN/m to 45 mN/m. A dynamic surface tension of the treatment liquid, measured under the condition where a life time is about 50 ms, is in the range of 33 mN/m to 45 mN/m.

Abstract: A water-based ink for ink jet recording, containing: a coloring agent; water; and a water-soluble organic solvent. The coloring agent contains a phosphate group-modified self-dispersing pigment. The water-based ink further contains at least one of a reducing sugar and a sugar alcohol and a calcium ion.

Abstract: A water-based ink for ink jet recording, containing: a coloring agent; water; and a water-soluble organic solvent. The coloring agent contains a phosphate group-modified self-dispersing pigment. The water-based ink further contains at least one selected from the group consisting of boric acid, diglycolic acid, and a chelating agent.

Abstract: An ink set containing a water-based ink for ink jet recording and a treatment liquid. The water-based ink contains a phosphate-group modified self-dispersing pigment, water, and a water-soluble organic solvent. The treatment liquid contains an aggregating agent, water, and a water-soluble organic solvent. A dynamic surface tension of the water-based ink, measured under the condition where a life time is about 50 ms, is in the range of 35 mN/m to 45 mN/m. A dynamic surface tension of the treatment liquid, measured under the condition where a life time is about 50 ms, is in the range of 33 mN/m to 45 mN/m.

Abstract: An ink set containing a water-based ink for ink jet recording and a treatment liquid. The water-based ink contains a phosphate group-modified self-dispersing pigment, water, and a water-soluble organic solvent. The treatment liquid contains a monovalent metal ion, water, and a water-soluble organic solvent.

Abstract: A water-based ink for ink jet recording, containing: a coloring agent; water; and a water-soluble organic solvent. The coloring agent contains a phosphate group-modified self-dispersing pigment. The water-based ink further contains at least one selected from the group consisting of boric acid, diglycolic acid, and a chelating agent.

Abstract: A water-based ink for ink jet recording, containing: a coloring agent; water; and a water-soluble organic solvent. The coloring agent contains a phosphate group-modified self-dispersing pigment. The water-based ink further contains at least one of a reducing sugar and a sugar alcohol and a calcium ion.

Abstract: An ink set for ink-jet recording contains a yellow ink, a magenta ink, and a cyan ink. Ink sets capable of forming composite black images having good color deterioration properties and ozone resistance may be prepared by selecting an appropriate combination of a yellow ink, a magenta ink, and a cyan ink.

Abstract: A water base ink for ink-jet recording is provided, which makes it possible to secure a high recording quality with a sharp image area edge by avoiding any blurring even when recording is performed on regular paper and which has satisfactory purge restoration performance. Therefore, no bubble remains in an ink flow passage, and no discharge failure is caused. Further, the discharge operation never becomes unstable. In the water base ink for ink-jet recording, the surface tension is not less than 40 mN/m, and the amount of dissolved oxygen is not more than 4 mg/L.

Abstract: An evaluation method for evaluating a pigment ink for ink-jet recording used together with a dye ink and containing a pigment and water includes an aggregation property evaluation method for the pigment in which 10 parts by weight of an aqueous sodium chloride solution is added to 100 parts by weight of the pigment ink; the evaluation method including first aggregation property evaluation adding an X wt % aqueous sodium chloride solution; and second aggregation property evaluation adding a Y wt % aqueous sodium chloride solution; wherein concentrations of the aqueous sodium chloride solutions are set to fulfill the following condition in the first and second aggregation property evaluations: 1.0?X<Y?2.5. The optical density of a printed matter and the dispersion stability of the pigment when the pigment ink is brought in contact with the dye ink can be easily evaluated before the printing.

Abstract: An ink set for ink-jet recording contains a yellow ink, a magenta ink, and a cyan ink. Ink sets capable of forming composite black images having good color deterioration properties and ozone resistance may be prepared by selecting an appropriate combination of a yellow ink, a magenta ink, and a cyan ink.

Abstract: An ink set for ink-jet recording contains a yellow ink, a magenta ink, and a cyan ink. Ink sets capable of forming images having good color deterioration properties and ozone resistance may be prepared by selecting an appropriate combination of a yellow ink, a magenta ink, and a cyan ink which exhibits certain ozone resistance properties.

Abstract: New blue inks are provided for inkjet printing, especially using piezoelectric printers, on papers which are typically difficult to print with good quality, high-contrast images. The inks are characterized by a color of the ink (color illumination D65) of L*: about 37±5, a*: about 7±7, b*: about ?27±8. The inks contain an aqueous vehicle including water and a humectant comprising a polyhydric alcohol, a penetrant, surfactant, and a blue dye. The relative amounts of the aqueous vehicle, the penetrant, the surfactant and the blue dye, are effective to provide an ink having a viscosity and surface tension effective for inkjet printing, especially for piezoelectric printing, having a viscosity of from about 2 to about 4 mPa·s and a surface tension of from 30 to 50 mN/m. Also provided are a process for printing an image and a printed image prepared using the ink.

Abstract: New blue inks are provided for inkjet printing, on papers which are typically difficult to print with good quality, high-contrast images. The inks are characterized by a color of the ink (color illumination D65) of L*: about 37±5, a*: about 7±7, b*: about ?27±8. The inks contain an aqueous vehicle including water and a humectant comprising a polyhydric alcohol, a water-soluble polymer effective to improve the “hold out” properties of the dye-based ink on paper, surfactant, and a blue dye. The relative amounts of the aqueous vehicle, the water-soluble polymer, the surfactant and the blue dye, are effective to provide an ink having a viscosity and surface tension effective for inkjet printing, having a viscosity of from about 2 to about 4 mPa·s and a surface tension of from 30 to 50 mN/m. Also provided are a process for printing an image and a printed image prepared using the ink.

Abstract: A fluorescent water base ink for ink-jet recording includes water, a first fluorescent dye, and a second fluorescent dye. The first fluorescent dye absorbs light in a first absorption wavelength region in an ultraviolet region to emit fluorescence, and the first fluorescent dye absorbs light in a second absorption wavelength region to emit no fluorescence. The second fluorescent dye absorbs light in an absorption wavelength region in the ultraviolet region, which is different from the first absorption wavelength region of the first fluorescent dye, to emit fluorescence. A wavelength region of the fluorescence of the second fluorescent dye is not overlapped with the first absorption wavelength region of the first fluorescent dye, but at least a part of the wavelength region of the fluorescence of the second fluorescent dye is overlapped with the second absorption wavelength region. The fluorescence intensity of the ink is increased.

Abstract: An ink for ink-jet recording includes a solvent dye in which a xanthene structure and a phthalide structure are spiro bound to each other. When the ink is stored in an ink cartridge containing a polyurethane foam and ink-jet recording is performed, a stable printing density may be achieved and changes in hue may be avoided.

Abstract: An ink for ink-jet recording includes a solvent dye in which a xanthene structure and a phthalide structure are spiro bound to each other. When the ink is stored in an ink cartridge containing a polyurethane foam and ink-jet recording is performed, a stable printing density may be achieved and changes in hue may be avoided.

Abstract: A fluorescent water base ink for ink-jet recording contains a first fluorescent dye and a second fluorescent dye. The first fluorescent dye has a first ultraviolet absorption wavelength region in an absorption spectrum and a first fluorescence emission wavelength region in a fluorescence spectrum. The second fluorescent dye has a second ultraviolet absorption wavelength region which is different from the first ultraviolet absorption wavelength region in an absorption spectrum and a second fluorescence emission wavelength region in a fluorescence spectrum. The first fluorescent dye further has an absorption wavelength region which is different from the first ultraviolet absorption wavelength region and which overlaps at least a part of the second fluorescence emission wavelength region.