A water-based ink includes a pigment, and water, in which a viscosity at 20° C. is in a range of 2 mPa.Math.s to 7 mPa.Math.s, and a yield value at 20° C. is less than 0.2 mPa, and the yield value at 20° C. when evaporating 25% of the water is less than 0.8 mPa.

A water-based ink includes a pigment, and water, in which a viscosity at 20° C. is in a range of 2 mPa.Math.s to 7 mPa.Math.s, and a yield value at 20° C. is less than 0.2 mPa, and the yield value at 20° C. when evaporating 25% of the water is less than 0.8 mPa.

Provided is an ink jet recording ink containing a near-infrared absorbing colorant represented by Formula 1, a polymerizable monomer, a polymerization initiator, and a dispersant, in which a content of the polymerizable monomer is 50% by mass or more with respect to a total amount of the ink jet recording ink, and a difference between an SP value of the polymerizable monomer and an SP value of the dispersant is 3.8 MPa.sup.1/2 to 16.0 MPa.sup.1/2. Also provided is an ink jet recording method.

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The description of a ring A, a ring B, X.sup.A, X.sup.B, G.sup.A, G.sup.B, kA, and kB in Formula 1 will not be repeated.

The present disclosure provides an ink for inkjet printing. The inkjet ink comprises a carbon black pigment dispersion. The carbon black pigment in the dispersion has low oil absorption.

The present disclosure provides an ink for inkjet printing. The inkjet ink comprises a carbon black pigment dispersion. The carbon black pigment in the dispersion has low oil absorption.

An aqueous radiation curable dispersant formulation includes water and styrene acrylic resin stabilized thioxanthone derivative photoinitiator particles dispersed in the water. The styrene acrylic resin stabilized thioxanthone derivative photoinitiator particles have a volume-weighted mean diameter of less than 40 nm. The styrene acrylic resin stabilized thioxanthone derivative photoinitiator particles include a water-insoluble, thioxanthone derivative photoinitiator core having one, two, or three units, wherein a structure of the unit is: and x=2-12. When the water-insoluble, thioxanthone derivative photoinitiator core includes two units or three units, the units are covalently bonded together.

The present invention provides an inkjet ink comprising: 5-40% by weight of an N-vinyl monomer selected from N-vinyl caprolactam, N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl carbazole, N-vinyl formamide, N-vinyl indole, N-vinyl imidazole, N-vinyl acetamide, and mixtures thereof, based on the total weight of the ink; one or more difunctional monomers in which the only radiation-curable functional groups present in the monomer are (meth)acrylate groups; 9% or less by weight of a monofunctional monomer, other than the N-vinyl monomer, together with a multifunctional monomer, based on the total weight of the ink; a radical photoinitiator; and a colouring agent. The present invention also provides a method of inkjet printing using the inkjet ink of the present invention and use of an N-vinyl monomer selected from N-vinyl caprolactam, N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl carbazole, N-vinyl formamide, N-vinyl indole, N-vinyl imidazole, N-vinyl acetamide, and mixtures thereof to increase the cure speed of an inkjet ink comprising one or more of difunctional monomers.

The present invention provides an inkjet ink comprising: 5-40% by weight of an N-vinyl monomer selected from N-vinyl caprolactam, N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl carbazole, N-vinyl formamide, N-vinyl indole, N-vinyl imidazole, N-vinyl acetamide, and mixtures thereof, based on the total weight of the ink; one or more difunctional monomers in which the only radiation-curable functional groups present in the monomer are (meth)acrylate groups; 9% or less by weight of a monofunctional monomer, other than the N-vinyl monomer, together with a multifunctional monomer, based on the total weight of the ink; a radical photoinitiator; and a colouring agent. The present invention also provides a method of inkjet printing using the inkjet ink of the present invention and use of an N-vinyl monomer selected from N-vinyl caprolactam, N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl carbazole, N-vinyl formamide, N-vinyl indole, N-vinyl imidazole, N-vinyl acetamide, and mixtures thereof to increase the cure speed of an inkjet ink comprising one or more of difunctional monomers.

The present invention provides a metal oxide dispersion comprises a metal oxide, a millbase and a dispersant. The dispersant in the metal oxide is selected from a group consisting of a phosphoric acid polyester copolymer, a trimethoxysilane compound, a triethoxysilanes compound, dimethylamino ethyl methacrylate (DMAEMA) and a combination thereof, and the dispersion is substantially free of water. The metal oxide dispersion of the invention is useful for manufacturing an inkjet ink to provide a high-quality color image on a contact lens or a mold so as to produce a colored contact lens.

The present invention provides a metal oxide dispersion comprises a metal oxide, a millbase and a dispersant. The dispersant in the metal oxide is selected from a group consisting of a phosphoric acid polyester copolymer, a trimethoxysilane compound, a triethoxysilanes compound, dimethylamino ethyl methacrylate (DMAEMA) and a combination thereof, and the dispersion is substantially free of water. The metal oxide dispersion of the invention is useful for manufacturing an inkjet ink to provide a high-quality color image on a contact lens or a mold so as to produce a colored contact lens.