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: The present invention provides an ink set comprising a plurality of ink compositions including: an ink composition A containing at least a polymerizable compound and a photopolymerization initiator; and an ink composition B containing at least a polymerizable group, wherein each ink composition is not curable by itself.

Abstract: It is an object of the present invention to provide a photo-curing ink composition having excellent curing properties while maintaining low viscosity and good preservation stability and to provide an ink jet recording method and an ink jet recording apparatus which can provide an image with high quality by using the ink composition. The photo-curing ink composition according to the present invention contains at least one of a compound having an allyl group and an N-vinyl compound as a polymerizable compound and contains at least one of thioxanthone and an amine as a polymerization accelerator. In the ink jet recording method and the ink jet recording apparatus according to the present invention, the photo-curing ink composition is used and the light irradiation starts 0.1 to 20 seconds after the discharge of the ink composition from a head to a 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.

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.

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: An ink set includes at least a magenta ink composition and a light magenta ink composition. The light magenta ink composition is formed with a pigment density lower than a pigment density of the magenta ink composition. A pigment used in the magenta ink composition is C.I. Pigment Violet 19, and a pigment used in the light magenta ink composition is C.I. Pigment Red 122.

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: The present invention provides an ink composition comprising at least a pigment and a water-soluble solvent, wherein the composition comprises an alkyl alcohol having 4 to 6 carbon atoms in an amount of 0.05 to 0.5% by weight.

Abstract: Disclosed is a liquid composition that, while maintaining good color developing properties and gloss, can realize good cleaning operation without staying of the liquid composition in a cleaning cap. The liquid composition is adapted for use with an ink composition for deposition on a recording medium and comprises a modified polyallylamine, a water soluble organic solvent, and water and is free from any colorant. The liquid composition and an ink composition each are deposited onto a recording medium to perform recording. A polymer comprising a recurring unit represented by formula (I) is used as the modified polyallylamine.

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 present invention relates to a polyallylamine-based high-molecular-weight polymer which is easily soluble in water and in an organic solvent and gives an excellently stable aqueous solution or organic solvent solution thereof which is suitable for use in the fields of fine chemicals such as the field of inkjet recording, and the polymer is a modified polyallylamine obtained by modifying a copolymer of N,N-dialkylallylamine and allylamine.

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: A titanium dioxide slurry for ink jet ink, which comprises water and surface-treated titanium dioxide particles dispersed in the water, the surface treatment being a treatment with an inorganic phosphoric acid compound. Also disclosed is an ink comprising the titanium dioxide slurry.

Abstract: Ink jet recording is carried out using an ink set including 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: An ink set, exhibiting good ink permeability and fixation, capable of yielding high quality images with no roughness, or an ink set capable of yielding text and/or images of outstanding light resistance, is provided. The ink set of the present invention comprises a dark ink composition and a light ink composition that, while being mutually the same color, are of different color density, and is characterized in that the dark ink composition and the light ink composition each comprise a pigment as a colorant and a resin as a dispersant, in that the ratio between the resin weight proportion B1 and the pigment weight proportion P1 in the dark ink composition (i.e. B1/P1) is lower than the ratio between the resin weight proportion B2 and the pigment weight proportion P2 in the light ink composition (i.e. B2/P2), and in that B1 and B2 differ from each other.

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: 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.

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: 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.