The present invention relates to [1] a pigment water dispersion containing pigment-containing crosslinked polymer particles, in which a crosslinked polymer in the particles is a polymer that is crosslinked with a compound represented by the general formula (1), and the pigment is a carbon black, and [2] a process for producing a pigment water dispersion containing pigment-containing crosslinked polymer particles, including the following steps: Step (1): subjecting a pigment mixture containing a water-dispersible polymer, a pigment and water to dispersion treatment, thereby obtaining an aqueous pigment dispersion solution containing pigment-containing polymer particles; and Step (2): mixing the aqueous pigment dispersion solution obtained in the step (1) and a compound represented by the general formula (1) to react the water-dispersible polymer with the compound to prepare a crosslinked polymer, thereby obtaining the pigment water dispersion containing pigment-containing crosslinked polymer particles.

Provided is a metal-particle dispersion composition as a composition containing dispersed metal particles and being suitable for use in aqueous coating compositions, etc., the metal-particle dispersion composition comprising 10-80 mass % metal particles, 0.01-10 mass % organic titanate compound in a chelate form, 1-40 mass % water, and 2-30 mass % organic solvent having a higher boiling point than water, the amounts being based on the whole composition, wherein the organic titanate compound is an organic compound represented by Ti(OR).sub.4 (the OR groups include at least one chelatable substituent based on triethanolamine) and the organic solvent having a higher boiling point than water is a C.sub.7 or lower alcohol compound.

A composition of matter includes a liquid and nanoparticles suspended in the liquid. The nanoparticles each include silica, alumina, and an organosilicon functional group having a molecular weight of at least 200. A method includes functionalizing a surface of nanoparticles with an organosilicon functional group and dispersing the nanoparticles in a liquid to form a suspension. The functional group has a molecular weight of at least 200. The nanoparticles each include silica and alumina at a surface thereof.

Provided are surface-modified inorganic compound particles having excellent dispersibility in a water soluble organic solvent, and also having excellent chemical stability in water.

Provided are Surface-modified particles, in which a surface of inorganic compound particle is modified with a compound represented by the following formula (1) or a salt thereof.

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[In formula (1), R.sup.1 represents an alkyl group having 1 to 4 carbon atoms or an alkenyl group having 2 to 4 carbon atoms.]

The present invention relates to [1] a process for producing a pigment water dispersion liquid of polymer particles containing an azomethine metal complex pigment (A), said process including the step of subjecting a mixture containing the azomethine metal complex pigment (A), an uncrosslinked aromatic group-containing polymer (b) and water to dispersion treatment using a medialess disperser at an accumulated input energy of not more than 5.0 kWh/kg, [2] a pigment water dispersion liquid containing an azomethine metal complex pigment (A) and a polymer dispersant (B), in which in an optical absorption spectrum of the pigment water dispersion liquid, a ratio of a maximum absorbance (A1.sub.max) in a wavelength range of not less than 440 nm and less than 465 nm to a maximum absorbance (A2.sub.max) in a wavelength range of not less than 420 nm and less than 440 nm [(A1.sub.max)/(A2.sub.max)] is not less than 1.000, and [3] a water-based ink for ink-jet printing, containing the aforementioned pigment water dispersion liquid.

The present application relates to the field of black coloring of materials made from wood, such as reconstituted wood panels or paper/cardboard. The black coloring composition for wood-based materials includes a black pigment, a reactive type black dye and water. It is also possible to prepare a dry extract for some special applications.

Provided are a titanium dioxide aqueous dispersion having high dispersibility and little aggregation or coarse particles, and a method for producing the same. The titanium dioxide aqueous dispersion contains titanium dioxide particles having a hydrophobic compound such as a higher fatty acid or a salt thereof on the surface, an aqueous dispersion medium, a nonionic surfactant having an HLB value of 10 or higher, and a basic compound such as an alkanolamine, and the pH is in the 8.5-13 range. The method for producing a titanium dioxide aqueous dispersion has a step for mixing the titanium dioxide particles having a hydrophobic compound on the surface, the aqueous dispersion medium, the nonionic surfactant having an HLB value of 10 or higher, and the basic compound to bring the pH of the aqueous dispersion into the 8.5-13 range.

The present invention relates to [1] a water-based pigment dispersion formed by dispersing a pigment in a water-based medium with a polymer dispersant, in which the polymer dispersant contains a (meth)acrylic resin (A) and a resin (B); and the resin (B) is at least one resin selected from the group consisting of a polyester resin (B1), an acid-modified polyolefin resin (B2) and a vinyl chloride-based resin (B3), and [2] a process for producing a water-based pigment dispersion, including the following steps 1 and 2: Step 1: subjecting a pigment mixture containing a pigment, an acid group-containing (meth)acrylic resin (A), and a resin (B) which is at least one resin selected from the group consisting of a polyester resin (B1), an acid-modified polyolefin resin (B2) and a vinyl chloride-based resin (B3) to dispersion treatment to obtain a dispersion; and Step 2: subjecting the dispersion obtained in the step 1 to crosslinking treatment with a crosslinking agent (C).

The present invention relates to [1] a process for producing a pigment water dispersion, including step 1 of mixing a water dispersion (A) formed by dispersing a pigment (I) with a water-dispersible polymer and a water dispersion (B) of a self-dispersible pigment (II) to obtain a water dispersion (C); and step 2 of subjecting the water dispersion (C) obtained in the step 1 to heat treatment at a temperature of not lower than 40 C. to obtain the pigment water dispersion, and [2] a pigment water dispersion containing a pigment (I) dispersed with a water-dispersible polymer and a self-dispersible pigment (II), in which the water-dispersible polymer is adsorbed onto the pigment (I) and the self-dispersible pigment (II).

A thermal inkjet dye sublimation ink consists of a disperse dye colorant dispersion, a co-solvent system, an additive, and a balance of water. The colorant dispersion is present in an amount ranging from about 1 wt % actives to about 7 wt % actives. The co-solvent system is present in a total amount ranging from about 12 wt % to about 25 wt %. The co-solvent system consists of glycerol present in an amount ranging from about 9 wt % to about 16 wt %, ethoxylated glycerol present in an amount ranging from 0 wt % to about 5 wt %, and a water soluble or water miscible organic solvent present in an amount ranging from 0 wt % to about 7 wt %. The additive is selected from the group consisting of a surfactant, a chelating agent, a buffer, a biocide, and combinations thereof.