Provided are a method for producing an aqueous inkjet pigment dispersion, including producing a mixed liquid of water, a pigment, a pigment dispersing polymer, and rosin acid in an amount of from 3% by mass to 30% by mass relative to the total mass of the pigment, and reducing the amount of rosin acid included in the produced mixed liquid, to less than 3.0% by mass relative to the total mass of the pigment; an aqueous inkjet pigment dispersion; and an aqueous inkjet ink.

Provided is a conductive ink including a conductive material and at least one benzoxazine-based compound. The conductive ink of the present invention can be easily formed into a thin film, is highly conductive after sintering, and has superior adhesion to various substrates. In addition, the use of the conductive ink according to the present invention facilitates the formation of a glossy, mirror-like metal thin film with high reflectance.

Provided is a conductive ink including a conductive material and at least one benzoxazine-based compound. The conductive ink of the present invention can be easily formed into a thin film, is highly conductive after sintering, and has superior adhesion to various substrates. In addition, the use of the conductive ink according to the present invention facilitates the formation of a glossy, mirror-like metal thin film with high reflectance.

An ink composition that contains light-emitting nanocrystalline particles, a photopolymerizable component containing at least one photopolymerizable compound and having a Hansen solubility parameter δp of 3.0 MPa.sup.0.5 or more, and a phosphite compound with a partial structure represented by the following formula (1).

##STR00001##

[In the formula (1), X.sup.1 to X.sup.3 independently denote an oxygen atom or a sulfur atom, R.sup.1 denotes an alkyl group, and * denotes a bonding arm.]

An active energy ray-curable composition includes one or more compounds expressed by Formula (1) and/or Formula (2) below:

##STR00001##

wherein R.sub.1 represents a —C.sub.15H.sub.31-2n group (n=0, 1, 2 or 3), and R.sub.2 represents a hydrogen or methyl group,

##STR00002##

wherein R.sub.3 represents a —C.sub.15H.sub.31-2n group (n=0, 1, 2 or 3), and R.sub.4 represents a hydrogen or methyl group.

Provided is a photo-curable inkjet printing ink composition, comprising (A) an acrylicated amine compound having two photopolymerizable functional groups and two amino groups in a molecule, (B) a (meth)acrylic monomer having an alkoxy group, and (C) at least one selected from the group consisting of hexanediol acrylate, 3-methyl-1,5-pentanediol diacrylate, dipropylene glycol diacrylate, and neopentyl glycol diacrylate hydroxypivalate, wherein a content of the component (A) is 3 to 18% by mass in the ink composition, wherein a content of the component (B) is 5 to 35% by mass in the ink composition, and wherein a content of the component (C) is 30 to 60% by mass in the ink composition.

Provided is a photo-curable inkjet printing ink composition, comprising (A) an acrylicated amine compound having two photopolymerizable functional groups and two amino groups in a molecule, (B) a (meth)acrylic monomer having an alkoxy group, and (C) at least one selected from the group consisting of hexanediol acrylate, 3-methyl-1,5-pentanediol diacrylate, dipropylene glycol diacrylate, and neopentyl glycol diacrylate hydroxypivalate, wherein a content of the component (A) is 3 to 18% by mass in the ink composition, wherein a content of the component (B) is 5 to 35% by mass in the ink composition, and wherein a content of the component (C) is 30 to 60% by mass in the ink composition.

The electroconductive inkjet ink disclosed herein contains at least inorganic powder containing high melting point metal particles, a dispersant, an organic solvent, and a poly(vinyl acetal) resin. In the electroconductive ink, the inorganic powder has an average primary particle diameter of 500 nm or less, a volume ratio of the inorganic powder is 7.5% by volume or lower, the ratio (S.sub.I/V.sub.D) of the specific surface area of the inorganic powder with respect to the volume of the dispersant is 0.25 or higher and 10 or lower, the poly(vinyl acetal) resin has an average molecular weight of 2.5×10.sup.4 or larger and 6.4×10.sup.4 or smaller, and the ratio (W.sub.PA/W.sub.S) of the weight of the poly(vinyl acetal) resin with respect to the weight of the organic solvent is 0.5% by weight or higher and 3% by weight or lower.

The electroconductive inkjet ink disclosed herein contains at least inorganic powder containing high melting point metal particles, a dispersant, an organic solvent, and a poly(vinyl acetal) resin. In the electroconductive ink, the inorganic powder has an average primary particle diameter of 500 nm or less, a volume ratio of the inorganic powder is 7.5% by volume or lower, the ratio (S.sub.I/V.sub.D) of the specific surface area of the inorganic powder with respect to the volume of the dispersant is 0.25 or higher and 10 or lower, the poly(vinyl acetal) resin has an average molecular weight of 2.5×10.sup.4 or larger and 6.4×10.sup.4 or smaller, and the ratio (W.sub.PA/W.sub.S) of the weight of the poly(vinyl acetal) resin with respect to the weight of the organic solvent is 0.5% by weight or higher and 3% by weight or lower.

The present invention concerns a method for obtaining polyaniline/reduced graphene oxide composites comprising the steps of dispersing the graphene oxide in an acid aqueous solution containing an emulsifying agent to obtain a graphene oxide dispersion; dissolving one or more aniline oligomers in an organic solvent to obtain an oligomer solution; mixing the oligomer solution with the graphene oxide dispersion, said oligomer being added in a stoichiometric excess compared to the quantity required to complete the graphene oxide reduction; adding to the suspension of the polyaniline/reduced graphene oxide composite an oxidizing agent in a stoichiometric quantity compared to said excess of oligomer so as to oxidize the excess of said oligomer to obtain a suspension of the polyaniline/reduced graphene oxide composite.