Abstract: There is provided an ink composition which can yield records possessing excellent rubbing/abrasion resistance and scratch resistance. Specifically, records possessing, excellent rubbing/abrasion resistance and scratch resistance can be produced by using an ink composition comprising: an alkali-soluble copolymer; water; a colorant; and at least one member selected from the group consisting of wax, a viscosity modifier, and a wetting agent. The alkali-soluble copolymer is a copolymer, with an acid value of not more than 40, which is produced by polymerizing an ethylenically unsaturated carboxylic acid monomer and other monomer copolymerizable with the ethylenically unsaturated carboxylic acid monomer in the presence of an alcoholic hydroxyl-containing water-soluble polymer compound or a copolymerizable surfactant and has been adjusted to a pH value, at which the copolymer is soluble in water, by the addition of an inorganic base.

Abstract: An ink composition is provided which can realize good images on plain paper, and, especially when used in an ink jet recording method, can have excellent ejection stability, storage stability, color development, and fixation and is much less likely to cause color bleeding and uneven printing and thus can realize good image quality. The ink composition comprises at least a pigment, a compound represented by formula (I), water, and a water-soluble organic solvent wherein R1 to R7 each independently represent an alkyl group; j and k are an integer of 1 or more; EO represents an ethyleneoxy group; PO represents a propyleneoxy group; and m+n is an integer of 1 or more.

Abstract: A problem of the present invention is to provide an ink set and an ink jet recording method, according to which a high-quality printed article can be provided for which deformation such as wrinkling does not occur, the color density is high, and there is little blotting or unevenness even if regular paper is used as the recording medium.

Abstract: A process for producing a pigment dispersion is disclosed. This process comprises the steps of: providing a mixture consisting essentially of a pigment, a dispersant, a polysiloxane surfactant and/or an alkanediol, a polyhydric alcohol, and water; and dispersing the ingredients of the mixture in one another. A process for producing an ink composition is also disclosed wherein the above pigment dispersion is mixed with a member selected from the group consisting of water, a surfactant, a wetting agent, a pH adjustor, and mixtures thereof. This ink composition can realize good image quality.

Abstract: The present invention provides an ink set comprising at least three color inks, which are yellow ink whose hue angle H°, as defined in the CIELAB color space on a recording medium (PM-photographic paper; same below), is in a range of about 80° to about 110°, magenta ink whose hue angle H° is in a range of about 330° to about 360°, and cyan ink whose hue angle H° is in a range of about 230° to about 260°, and further comprising ink (A) and/or ink (B) described below. With the present ink set, it is possible to provide a highly reliable ink set that can be used in inkjet recording and can produce printed matter having a wide color reproduction range, high color saturation, good graininess, and an adequate glossy look.

Abstract: An oil based ink composition for ink jet recording containing, as an organic solvent, a mixture of a diethylene glycol compound that is liquid at ordinary temperature under atmospheric pressure and a dipropylene glycol compound that is liquid at ordinary temperature under atmospheric pressure at a diethylene glycol compound to dipropylene glycol compound weight ratio of 20:80 to 80:20, and an ink jet recording method using the oil based ink composition are disclosed. The oil based ink composition for ink jet recording provides high quality images with high gloss, excellent abrasion resistance and water resistance, and freedom from blur or bleeding.

Abstract: High-quality images that have excellent coloring properties and glossiness in the recorded images can be obtained by depositing a colorant-containing color ink composition and a clear ink composition containing water and cationic resin, but no colorant on a recording medium to form a record. The cationic resin is preferably a polyethyleneimine with a weight-average molecular weight (Mw) of 100,000 or less.

Abstract: An object of the present invention is to provide ink compositions possessing excellent lightfastness. The cyan ink composition according to the present invention comprises, as colorants, a cyan colorant selected from the group consisting of C.I. Pigment Blue 15:3, C.I. Pigment Blue 15:4, and a mixture of the cyan colorants, and a yellow colorant having a higher fading rate than the cyan colorant. The magenta ink composition according to the present invention comprises, as colorants, a magenta colorant selected from the group consisting of C.I. Pigment Red 122, C.I. Pigment Red 202, C.I. Pigment Red 209, and mixtures of the magenta colorants, and a yellow colorant having a higher fading rate than the magenta colorant.

Abstract: The present invention is directed to a yellow ink which can realize images possessing excellent color reproduction and waterfastness. Images possessing very excellent color reproduction and lightfastness can be realized by using a yellow ink composition comprising C.I. Pigment Yellow 128 and C.I. Pigment Yellow 110 as a colorant, or by using a yellow ink set comprising a first yellow ink composition containing C.I. Pigment Yellow 128 and a second yellow ink composition containing C.I. Pigment Yellow 110.

Abstract: It is an object of the present invention to provide an ink jet recording method and ink set with which recorded material with excellent gloss and greatly reduced gloss unevenness can be easily obtained without higher costs being entailed, the ink jet recording apparatus having to be modified or made larger, etc., and to provide an ink jet recording method with which a high-quality image can be obtained with a low gloss ratio (maximum value/minimum value) dependent on duty, as well as recorded material produced by this method. The present invention provides an ink jet recording method, in which a pigment ink composition and a clear ink composition containing a resin component are discharged to record information on a recording medium, wherein the discharge amount of the pigment ink composition and/or the discharge amount of the clear ink composition is adjusted so that the gloss will be substantially uniform over the entire recording surface of the recording medium after recording.

Abstract: It is an object of the present invention to provide an ink set which has a superior effect in suppressing gloss unevenness of printed images, and which thus makes it possible to obtain images that have a uniform gloss. The present invention achieves this object by providing an ink set comprising one or more color ink compositions containing a pigment as a coloring agent and a dispersing resin that is used to disperse this pigment, and one or more clear ink compositions which contain an aqueous polymer but which contain no coloring agent, wherein the dispersing resin and the aqueous polymer belong to a common category so that the 60° specular gloss (according to JIS Z 8741) of the printed images that are formed by the abovementioned color ink compositions and/or the abovementioned clear ink composition is substantially uniform.

Abstract: Disclosed is a black ink composition containing a carbon black and a pigment represented by the following general formula (1): wherein p represents an integer of from 0 to 3. Also disclosed is an ink set containing at least one kind of such a black ink composition as at least one of a black ink composition and a light black ink composition.

Abstract: A nozzle surface (13) is sealed by a cap member (44) in a state in which an ink solution is accumulated in a sealed hollow portion (45). After the nozzle surface (13) is sealed, piezoelectric vibrators (35) are driven by applying thereto a high-frequency drive signal of a frequency higher than a drive frequency for ejecting the ink solution toward recording paper, thereby causing cavitation in the ink solution. The firmly adhering thickened ink and solidified ink occurring in nozzle openings (29) are broken or exfoliated by bubbles caused by this cavitation. Subsequently, the suction operation is performed to remove the thickened ink and the solidified ink from the nozzle portions.

Abstract: An ink composition for ink jet recording is provided which possesses excellent printing stability, ejection stability, and storage stability and can yield good images, especially images having excellent color reproduction. The ink composition for ink jet recording comprises at least a colorant, a penetrating agent, a water-soluble organic solvent, and water, the colorant comprising a pigment coated with a resin which is an anionic group-containing polymer, the content of the pigment being in the range of 35 to 90% by weight based on the colorant, the penetrating agent comprising an acetylene glycol surfactant and/or a polysiloxane surfactant, the water-soluble organic solvent comprising at least an alkyl ether derivative of a polyhydric alcohol, wherein the alkyl has 3 or more carbon atoms, and/or a 1,2-alkanediol.

Abstract: A process for producing a pigment dispersion is disclosed. This process comprises the steps of: providing a mixture consisting essentially of a pigment, a dispersant, a polysiloxane surfactant and/or an alkanediol, a polyhydric alcohol, and water; and dispersing the ingredients of the mixture in one another. A process for producing an ink composition is also disclosed wherein the above pigment dispersion is mixed with a member selected from the group consisting of water, a surfactant, a wetting agent, a pH adjustor, and mixtures thereof. This ink composition can realize good image quality.

Abstract: Ink jet recording is carried out using an ink set comprising a clear ink composition that contains polymer fine particles and does not contain a colorant, a yellow ink composition, a magenta ink composition, a cyan ink composition, a red ink composition, a violet ink composition, and a black ink composition, whereby a high-quality recorded article having excellent recorded image coloration and glossiness can be obtained.

Abstract: The invention provides ink which is best suited for inkjet printing of a printed substrate. The ink is a photo polymerizing type water-base ink including at least a colorant, a photo polymerization resin, a photo initiator, and a water-base solvent. The photo polymerization resin includes oligomer particles in an emulsion state and monomers which reside in the oligomer particles. The water-base ink contains, with content ratio in terms of the percentage weight, 5% of ethyleneglycol, and between 0.1% to 10% of 2-pyrrolidone and N-acryloyl morpholine combined.

Abstract: The present invention provides an ink set for which metamerism (the phenomenon in which the colors of a printed article (color recorded image) differ according to the light source used when viewing the printed article) is reduced. The ink set of the present invention comprises a yellow ink, a magenta ink and a cyan ink, wherein, when color mixing is carried out through ink jet output of the inks in the ink set such that the output color under a D50 light source is such that the spatial coordinates (L*,a*,b*) stipulated by the CIE are (50,0,0), the difference between the maximum value and the minimum value of the reflectance of the output color over a light source wavelength range of 400 to 700 nm is not more than 20%.

Abstract: A problem of the present invention is to provide an ink set and an ink jet recording method, according to which a high-quality printed article can be provided for which deformation such as wrinkling does not occur, the color density is high, and there is little blotting or unevenness even if regular paper is used as the recording medium.

Abstract: An object of the present invention is to provide an ink compositions which, when used with an ink jet recording apparatus, can realize excellent ink ejection stability while maintaining safety and satisfactory penetration of ink. The ink composition according to the present invention comprises at least a colorant, a humectant, a glycol monoether as a penetrating agent, a 1,2-alkanediol, and water, the weight ratio of the glycol monoether to the 1,2-alkanediol being in the range of 1:5 to 5:1. According to another aspect of the present invention, there is provided an ink composition comprising at least a pigment, a dispersant for dispersing the pigment, a 1,2-alkanediol, and water as a main solvent, the content of the 1,2-alkanediol being 0.5 to 10% by weight based on the total amount of the ink composition.