A method of inkjet printing a colour image including a metallic or pearlescent colour includes the steps of applying on part of an ink receiver a layer containing a pearlescent or metallic pigment having a volume mean particle size of at least 3.0 μm as measured by laser diffraction; and inkjet printing on part of the layer containing the pearlescent or metallic pigment a layer with a white inkjet ink containing a white pigment having an average particle size between 250 and 400 nm as measured by differential centrifugal sedimentation.

A metallic nanoparticle dispersion includes metallic nanoparticles, a liquid carrier, and a dispersion-stabilizing compound according to Formulae I, II, III or IV,

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wherein Q represents the necessary atoms to form a substituted or unsubstituted a five or six membered heteroaromatic ring; M is selected from the group consisting of a proton, a monovalent cationic group and an acyl group; R1 and R2 are independently selected from the group consisting of a hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl or heteroaryl group, a hydroxyl group, a thioether, an ether, an ester, an amide, an amine, a halogen, a ketone and an aldehyde, R1 and R2 may represent the necessary atoms to form a five to seven membered ring; R3 to R5 are independently selected from the group consisting of a hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl or heteroaryl group, a hydroxyl group, a thiol, a thioether, a sulfone, a sulfoxide, an ether, an ester, an amide, an amine, a halogen, a ketone, an aldehyde, a nitrile and a nitro group; and R4 and R5 may represent the necessary atoms to form a five to seven membered ring.

The present invention relates to an ink composition for 3D printing, a 3D printer and a method of controlling the 3D printer. An ink composition for 3D printing according to an aspect of the present invention may include surface-modified inorganic particles, a photocurable material crosslinked with the surface-modified inorganic particles and a photoinitiator which cures the photocurable material.

The present invention relates to an ink composition for 3D printing, a 3D printer and a method of controlling the 3D printer. An ink composition for 3D printing according to an aspect of the present invention may include surface-modified inorganic particles, a photocurable material crosslinked with the surface-modified inorganic particles and a photoinitiator which cures the photocurable material.

An ink includes a volatile solvent, an inorganic hollow particle, and a calcium ion, wherein the calcium ion has a proportion of from 0.5 to 250 ppm in the ink and the inorganic hollow particle has a 50 percent cumulative particle diameter of from 50 to 350 nm.

An ink includes a volatile solvent, an inorganic hollow particle, and a calcium ion, wherein the calcium ion has a proportion of from 0.5 to 250 ppm in the ink and the inorganic hollow particle has a 50 percent cumulative particle diameter of from 50 to 350 nm.

To provide an ink jet recording method excellent in a fixability of an image, capable of recording an image excellent in optical density, and excellent in a recoverability, when it uses a recording apparatus having a line head. This method records an image by using an ink jet recording apparatus equipped with a line head having an ejection nozzle of a pigment-containing aqueous ink and a mechanism for recovering an ejection state of the aqueous ink from the nozzle and applying the ink to a recording medium. The pigment has an average particle diameter of 80 nm or more, the ink has a dynamic surface tension of 55 mN/m or less at a lifetime of 10 milliseconds, the recovery mechanism includes a mechanism for causing the ink in the nozzle to flow, and the viscosity of the ink in the nozzle is reduced.

To provide an ink jet recording method excellent in a fixability of an image, capable of recording an image excellent in optical density, and excellent in a recoverability, when it uses a recording apparatus having a line head. This method records an image by using an ink jet recording apparatus equipped with a line head having an ejection nozzle of a pigment-containing aqueous ink and a mechanism for recovering an ejection state of the aqueous ink from the nozzle and applying the ink to a recording medium. The pigment has an average particle diameter of 80 nm or more, the ink has a dynamic surface tension of 55 mN/m or less at a lifetime of 10 milliseconds, the recovery mechanism includes a mechanism for causing the ink in the nozzle to flow, and the viscosity of the ink in the nozzle is reduced.

A metallic nanoparticle composition includes metallic nanoparticles and a non-aqueous polar protic solvent. The non-aqueous polar protic solvent has two hydroxyl groups, a boiling point of at least 280° C. at 760 mm Hg, and a viscosity in a range of 45 cP to 65 cP at 20° C. Polyvinylpyrrolidone (PVP) is present on the metallic nanoparticle surfaces. A concentration of metals in the metallic nanoparticle composition is in a range of 60 wt% to 90 wt% and a concentration, in aggregate, of solvents having a boiling point of less than 280° C. at 760 mm Hg in the metallic nanoparticle composition does not exceed 3 wt%.

A metallic nanoparticle composition includes metallic nanoparticles and a non-aqueous polar protic solvent. The non-aqueous polar protic solvent has two hydroxyl groups, a boiling point of at least 280° C. at 760 mm Hg, and a viscosity in a range of 45 cP to 65 cP at 20° C. Polyvinylpyrrolidone (PVP) is present on the metallic nanoparticle surfaces. A concentration of metals in the metallic nanoparticle composition is in a range of 60 wt% to 90 wt% and a concentration, in aggregate, of solvents having a boiling point of less than 280° C. at 760 mm Hg in the metallic nanoparticle composition does not exceed 3 wt%.