An object of the present invention is to provide an active energy ray-curable lithographic ink that exhibits good adhesion to a plastic film and does not cause a decrease in the adhesion capability even during hot-water treatment. The present invention encompasses a printing ink that includes (a) a urethane (meth)acrylate and (c) another polymerizable monomer, wherein the printing ink has an ink tack value of 5.0 or more and 18.0 or less and a viscosity (C) and a viscosity (B) that are both 5 Pa.Math.s or more and 100 Pa.Math.s or less, as measured at a rotational speed of 20 rpm and a rotational speed of 50 rpm respectively at 35° C., using a cone-plate rotating viscometer, and wherein the viscosity ratio (B)/(C) is 0.60 or more and 1.00 or less.

An ink set for single-pass printing including at least a cyan ink, a magenta ink, a yellow ink, and a gray ink, wherein the magenta ink satisfies a specific condition regarding spectral reflectance, and the gray ink has a spectral reflectance at a wavelength of 500 nm of 20 to 70% and satisfies the specific condition regarding spectral reflectance.

A curable ink composition capable of forming a cured product with a high refractive index and applicable to the inkjet method, a cured product of the curable ink composition, and a nanocomposite having a film composed of the cured product of the curable ink composition. The curable ink composition includes a photopolymerizable compound and metal compound nanocrystals, using a sulfide compound having specific structure and a (meth)acrylate compound (as the photopolymerizable compound, and using zirconium oxide nanocrystals as the metal compound nanocrystals.

The present invention is related to a method of curing a coated product comprising a substrate and a UV-curable coating composition applied onto a surface of said substrate, the method comprising the steps of transporting said coated product, by means of a web path, into a curing unit comprising a rotating unit, preferably a cylindrical body, and a treatment area formed between said rotating unit and said web path, said rotating unit and said web path having an even surface, wherein said coated product when being transported through said treatment area contacts the rotating unit and the web path so that no free areas between the coated product and the cylindrical body and the web path are present in said treatment area, and UV-curing said coated product present in said treatment area.

The present invention is related to a method of curing a coated product comprising a substrate and a UV-curable coating composition applied onto a surface of said substrate, the method comprising the steps of transporting said coated product, by means of a web path, into a curing unit comprising a rotating unit, preferably a cylindrical body, and a treatment area formed between said rotating unit and said web path, said rotating unit and said web path having an even surface, wherein said coated product when being transported through said treatment area contacts the rotating unit and the web path so that no free areas between the coated product and the cylindrical body and the web path are present in said treatment area, and UV-curing said coated product present in said treatment area.

There is provided a maintenance liquid, which is used in maintenance of a device equipped with a discharge head for discharging an ultraviolet ray curable-type composition containing the acyl phosphine oxide-based photopolymerization initiator toward an attachment object, including a polymerizable compound in which a saturation solubility of an acyl phosphine oxide-based photopolymerization initiator at 20° C. is equal to or greater than 5.0% by mass.

There is provided a maintenance liquid, which is used in maintenance of a device equipped with a discharge head for discharging an ultraviolet ray curable-type composition containing the acyl phosphine oxide-based photopolymerization initiator toward an attachment object, including a polymerizable compound in which a saturation solubility of an acyl phosphine oxide-based photopolymerization initiator at 20° C. is equal to or greater than 5.0% by mass.

Described is an energy curable ink for use in the production of layered composites the ink comprising 3 to 50% by weight of aminoacrylate as defined herein, 5 to 60% by weight of hydroxyl functional acrylate monomer and wherein the non-volatile content of the ink is not less than 45% by weight. Also described is a layered composite having a layer of the energy curable ink on a substrate and a process for producing a layered composite in which the energy curable ink according to the present invention is printed onto a substrate and then cured.

Described is an energy curable ink for use in the production of layered composites the ink comprising 3 to 50% by weight of aminoacrylate as defined herein, 5 to 60% by weight of hydroxyl functional acrylate monomer and wherein the non-volatile content of the ink is not less than 45% by weight. Also described is a layered composite having a layer of the energy curable ink on a substrate and a process for producing a layered composite in which the energy curable ink according to the present invention is printed onto a substrate and then cured.

A photopolymerizable composition comprises at least a polymerizable resin, a photosensitizer, an annihilator, and a photoinitiator. The photosensitizer is formulated to absorb an excitation light signal received in a first range of wavelengths. The annihilator is formulated to emit a light signal in a second range of wavelengths different from the first. During the absorption of light by the photosensitizer in the first range of wavelengths, the annihilator emits a light signal in the second range, a photon energy of the emitted light signal being greater than a photon energy of the light signal received by the photosensitizer. The annihilator is also formulated to implement an energy transfer mechanism to excite the photoinitiator for polymerization of the resin. The excited photoinitiator is formulated to generate at least one polymerizable initiator to cause the polymerization reaction. Related methods, such as three-dimensional printing methods, and materials are also disclosed.