An ink is provided which can prevent the deformation and degradation of resin products by printed items, and is also suitable for inkjet printing. The oil-based inkjet ink contains a colorant and a fatty acid ester-based solvent represented by general formula (1) shown below and having 12 to 23 carbon atoms in one molecule. ##STR00001##
(In general formula (1), each of R.sup.1 and R.sup.2 independently represents an alkyl group, and at least one of the alkyl groups of R.sup.1 and R.sup.2 is a branched alkyl group having a side chain of at least 4 carbon atoms.).

An ink including a pigment, water, and a resin is provided. An image formed with the ink on a print medium has a tack force of 6 gf or greater but 13 gf or less when measured at a probe temperature of 100 degrees C., where the image is a solid image formed at a resolution of 1,200 dpi, subsequently irradiated with light of 395 nm for 0.6 seconds, and left to stand at normal temperatures and normal humidities for 30 seconds.

An ink including a pigment, water, and a resin is provided. An image formed with the ink on a print medium has a tack force of 6 gf or greater but 13 gf or less when measured at a probe temperature of 100 degrees C., where the image is a solid image formed at a resolution of 1,200 dpi, subsequently irradiated with light of 395 nm for 0.6 seconds, and left to stand at normal temperatures and normal humidities for 30 seconds.

To provide an inkjet printing apparatus that improves the smoothness of an ink surface and improves image quality. Provided is an inkjet printing apparatus for printing a UV curable ink onto a print medium. The inkjet printing apparatus including: an ejection unit configured to eject the UV curable ink; and a UV light source configured to irradiate, with ultraviolet light, the UV curable ink landed on the print medium, the print medium being formed from vinyl chloride. The inkjet printing apparatus further includes a heating unit configured to heat the print medium. The heating unit either heats the print medium to a temperature at which a solvent contained in the UV curable ink landed on the print medium does not volatilize or heats the print medium in a state in which the UV curable ink that lands on the print medium contains substantially no solvent.

To provide an inkjet printing apparatus that improves the smoothness of an ink surface and improves image quality. Provided is an inkjet printing apparatus for printing a UV curable ink onto a print medium. The inkjet printing apparatus including: an ejection unit configured to eject the UV curable ink; and a UV light source configured to irradiate, with ultraviolet light, the UV curable ink landed on the print medium, the print medium being formed from vinyl chloride. The inkjet printing apparatus further includes a heating unit configured to heat the print medium. The heating unit either heats the print medium to a temperature at which a solvent contained in the UV curable ink landed on the print medium does not volatilize or heats the print medium in a state in which the UV curable ink that lands on the print medium contains substantially no solvent.

The present invention relates to [1] a water-based ink for ink-jet printing which can be prevented from suffering from increased viscosity and flocculation of the ink upon storage thereof even when used in the form of a system containing a large amount of a solvent, said water-based ink for ink-jet printing containing crosslinked polymer particles containing a pigment having an indanthrone skeleton, an organic solvent and water, in which a crosslinking rate of the crosslinked polymer is not less than 10 mol % and not more than 90 mol %, and a content of the organic solvent in the water-based ink is not less than 30% by mass and not more than 65% by mass, and [2] an ink-jet printing method including the steps of loading the water-based ink as described in the above [1] to an ink-jet printing apparatus, and ejecting the water-based ink in the form of droplets of the ink onto a printing medium to form characters or images on the printing medium.

The present invention relates to [1] a water-based ink for ink-jet printing which can be prevented from suffering from increased viscosity and flocculation of the ink upon storage thereof even when used in the form of a system containing a large amount of a solvent, said water-based ink for ink-jet printing containing crosslinked polymer particles containing a pigment having an indanthrone skeleton, an organic solvent and water, in which a crosslinking rate of the crosslinked polymer is not less than 10 mol % and not more than 90 mol %, and a content of the organic solvent in the water-based ink is not less than 30% by mass and not more than 65% by mass, and [2] an ink-jet printing method including the steps of loading the water-based ink as described in the above [1] to an ink-jet printing apparatus, and ejecting the water-based ink in the form of droplets of the ink onto a printing medium to form characters or images on the printing medium.

Provided is a copper powder manufactured by means of a wet method, wherein the absolute value of the zeta potential of the copper powder is at least 20 mV. The copper powder can be manufactured so as to reduce the burden of the steps of crushing a dry cake and classification, and there is a sufficient reduction in residual secondary particles.

An aqueous primer composition includes a water-soluble multivalent metal salt, a polyester-based polyurethane emulsion, and water. A set includes the aqueous primer composition and an inkjet recording ink composition. A printed matter obtained by using the set includes a base material layer, a primer layer containing the water-soluble multivalent metal salt and the polyester-based polyurethane, and a printing layer. The aqueous primer can offer excellent preservation stability, and can allow for formation of a printing layer having high adhesion, capable of forming high-quality images with little bleeding/mottled appearance when printing images, text, etc., to form a printing layer on a plastic film or other nonabsorbent medium using inkjet recording ink compositions, offering excellent water resistance and lamination suitability.

An aqueous ink comprising a dispersion of a capsule composed of a polymeric shell surrounding a core, the core comprises one or more chemical reactants capable of forming a reaction product upon application of heat and/or radiation, the shell is stabilized by cationic dispersing groups and a colorant stabilised by cationic dispersing groups.