Abstract: An ink jet recording ink comprising at least a copper phthalocyanine dye represented by the following general formula (1) and a compound represented by the following general formula (2):

Abstract: An ink comprising yellow colorants and a colorant having a phthalocyanine skeleton, in which the yellow colorants are at least a colorant represented by the following general formula I and C.I.

Abstract: An ink-jet ink comprises water, a water-soluble coloring material having a molecular weight of 600 or less as a free acid form, at least two kinds of water-soluble organic solvents, and urea or a derivative thereof. The vapor pressures at 25° C. of the at least two kinds of water-soluble organic solvents are lower than that of water. The water-soluble organic solvents include a water-soluble organic solvent A and a water-soluble organic solvent B. The solubility of the water-soluble coloring material in the water-soluble organic solvent A is higher than its solubility in water, while its solubility in the water-soluble organic solvent B is equal to or lower than its solubility in water. The difference between the solubilities of the water-soluble coloring material in the water-soluble organic solvent A and in the water-soluble organic solvent B is 10% or more.

Abstract: An ink comprising yellow colorants and a colorant having a phthalocyanine skeleton, in which the yellow colorants are at least a colorant represented by the following general formula I and C.I. Direct Yellow 132.

Abstract: An ink jet recording ink comprising at least a copper phthalocyanine dye represented by the following general formula (1) and a compound represented by the following general formula (2):

Abstract: An ink-jet ink comprises water, a water-soluble coloring material having a molecular weight of 600 or less as a free acid form, at least two kinds of water-soluble organic solvents, and urea or a derivative thereof. The vapor pressures at 25° C. of the at least two kinds of water-soluble organic solvents are lower than that of water. The water-soluble organic solvents include a water-soluble organic solvent A and a water-soluble organic solvent B. The solubility of the water-soluble coloring material in the water-soluble organic solvent A is higher than its solubility in water, while its solubility in the water-soluble organic solvent B is equal to or lower than its solubility in water. The difference between the solubilities of the water-soluble coloring material in the water-soluble organic solvent A and in the water-soluble organic solvent B is 10% or more.

Abstract: Disclosed herein is an ink-jet recording system which employs an ink-jet recording apparatus including a recording-medium-holding part for a recording medium having an ink-receiving layer on a base material and an ink-holding part for a pigment ink to record an image on the ink-receiving layer of the recording medium fed from the recording-medium-holding part using the pigment ink fed from the ink-holding part, wherein (1) the ink-receiving layer of the recording medium is a porous layer comprising alumina hydrate and a resin binder and has a pore volume ranging from 0.1 to 1.0 ml/g; and (2) the pigment ink comprises an aqueous medium, a resin and a pigment, the particle diameter of the pigment substantially falls within a range of from 10 to 500 nm, and the proportion of the pigment particles having a particle diameter of 300 to 500 nm is at most 30% based on the total number of particles of the pigment.

Abstract: The invention provides an ink set, a process for forming a colored portion and an ink-jet recording apparatus which are used for obtaining higher-quality ink-jet recorded articles. The ink set includes an aqueous ink containing at least an ultrafinely particulate pigment as a coloring material and an aqueous liquid composition containing fine particles, dispersed therein and electrically charged at the surface in a polarity opposite to the ink.

Abstract: An ink set for ink-jet recording that includes a plurality of inks containing coloring materials insoluble in water to form a high quality ink-jet recording image is provided. The water-based ink set for ink-jet recording includes a black ink and a color ink, wherein the black ink contains a carbon black as a coloring material having a volume average particle diameter determined by dynamic light scattering of not less than 50 nm, the color ink contains a pigment as a coloring material having a volume average particle diameter determined by dynamic light scattering of not more than 60 nm, and an accumulative 90% particle diameter of volume particle size distribution of not more than 100 nm, the volume average particle diameter of the carbon black of the black ink is larger than the volume average particle diameter of the pigment of the color ink, and the black ink has a surface tension higher than that of the color ink.

Abstract: Aqueous pigment ink and organic pigment powder are used for ink-jet recording to form high quality images. Organic pigment powder is prepared by finely granulating an organic pigment containing anthraquinone as principal ingredient by means of a vapor phase method to such an extent that the produced powder shows a number average particle diameter of primary particles of 10 to 50 nm. An aqueous ink contains such organic pigment powder.

Abstract: An ink set for ink-jet recording that comprises a plurality of inks containing coloring materials insoluble in water to form a high quality ink-jet recording image is provided. The water-based ink set for ink-jet recording comprises a black ink and a color ink, wherein the black ink contains a carbon black as a coloring material having a volume average particle diameter determined by dynamic light scattering of not less than 50 nm, the color ink contains a pigment as a coloring material having a volume average particle diameter determined by dynamic light scattering of not more than 60 nm, and an accumulative 90% particle diameter of volume particle size distribution of not more than 100 nm, the volume average particle diameter of the carbon black of the black ink is larger than the volume average particle diameter of the pigment of the color ink, and the black ink has a surface tension higher than that of the color ink.

Abstract: The invention provides an ink set, a process for forming a colored portion and an ink-jet recording apparatus which are used for obtaining higher-quality ink-jet recorded articles. The ink set comprises an aqueous ink containing at least an ultrafinely particulate pigment as a coloring material and an aqueous liquid composition containing fine particles, dispersed therein and electrically charged at the surface in a polarity opposite to the ink.

Abstract: Aqueous pigment ink and organic pigment powder is used for ink-jet recording to form high quality images. Organic pigment powder is prepared by finely granulating an organic pigment containing anthraquinone as principal ingredient by mean of a vapor phase method to such an extent that the produced powder shows a number average particle diameter of primary particles of 10 to 50 nm. Aqueous ink contains such organic pigment powder.

Abstract: Disclosed herein is an ink-jet recording system which employs an ink-jet recording apparatus comprising a recording-medium-holding part for a recording medium having an ink-receiving layer on a base material and an ink-holding part for a pigment ink to record an image on the ink-receiving layer of the recording medium fed from the recording-medium-holding part using the pigment ink fed from the ink-holding part, wherein

Abstract: An ink set having (i) a black ink having a surface tension of not less than 40 dyne/cm, the black ink including a first dye; and (ii) at least one color ink having a surface tension of not more than 40 dyne/cm, the at least one color ink including a second dye which is rendered insoluble by the first dye when the black ink and the at least one color ink are mixed.

Abstract: Provided is an ink-jet color recording process to form color images on a recording medium by an ink-jet system applying a plurality of colored pigment-based inks, wherein each of the colored pigment inks comprises a pigment dispersant, and a pigment dispersant contained in at least one of colored pigment-based inks is different from a pigment dispersant contained in the remaining colored pigment-based inks.

Abstract: A recording medium is composed of a substrate and an ink receiving layer provided on at least one side of the substrate, wherein the ink receiving layer is composed of a composition or a cured product thereof containing at least (A) a polyvinyl acetal resin having acetal groups, acetyl groups and hydroxyl groups, (B) a monomer having an active energy ray curable ethylenic unsaturated group, and (C) a cationic resin, at a ratio (B)/(A) within the range of 1/100 to 5/1, and a ratio (C)/((A)+(B)) of 0.5/100 to 30/100.

Abstract: An ink absorbent member is prepared for holding an ink stored in an ink storing section in an ink jet cartridge. The ink absorbent member contains not more then 0.20% by weight, on the basis of the member, of a fraction of soluble matters in a liquid containing an organic polar solvent incapable of reacting with the ink absorbent member such as monohydric alcohols or alkyl ethers of polyhydric alcohols.

Abstract: Disclosed herein is an ink-jet recording method in which at least four inks composed of three color inks of cyan, magenta and yellow colors and a colorless ink containing a penetrant are used to record a color image, wherein the recording is conducted so as to overlap the penetrant-containing colorless ink and the color inks each other in a region along boundary lines to be defined by differences in hue of an image to be formed with the color inks, and to form an image with the color inks alone in other regions than the above region.

Abstract: An image forming method that forms an image using an ink and a liquid composition by a process comprising the steps of;(A) imparting a black ink to an image forming area of a recording medium by ink-jet recording; the black ink comprising a water-soluble black dye and a black pigment as coloring matters, and a liquid medium in which the coloring matters are dissolved or dispersed; and(B) imparting a liquid composition different from the ink to the image forming area.