The present invention provides an inkjet ink for a ceramic substrate, the inkjet ink making it possible to prevent a printed layer from peeling away after firing and allowing a desired image to be better fixed on a ceramic substrate. In the inkjet ink for a ceramic substrate disclosed here, the proportion of a monofunctional monomer in a monomer component is at least 90 mass %, the volume ratio of an inorganic solid relative to the total volume of the inkjet ink is 10 vol % to 20 vol %, and the ratio of the content of an N-vinyl compound to that of the monomer component (N-vinyl compound/monomer component) in the inkjet ink is 0.05 to 0.8 in terms of mass.

The present invention provides an inkjet ink for a ceramic substrate, the inkjet ink making it possible to prevent a printed layer from peeling away after firing and allowing a desired image to be better fixed on a ceramic substrate. In the inkjet ink for a ceramic substrate disclosed here, the proportion of a monofunctional monomer in a monomer component is at least 90 mass %, the volume ratio of an inorganic solid relative to the total volume of the inkjet ink is 10 vol % to 20 vol %, and the ratio of the content of an N-vinyl compound to that of the monomer component (N-vinyl compound/monomer component) in the inkjet ink is 0.05 to 0.8 in terms of mass.

The present invention pertains to a photocurable composition for a 3D printer for producing a transparent orthodontic device. A photocurable composition for a 3D printer can be provided, which has excellent physical properties such as thermal properties, strength, elastic modulus, and tensile elongation, and when used in a patient-customized transparent orthodontic device, the orthodontic device can reduce the pain felt by patients and can enhance orthodontic correction effectiveness due to being closely fitted to the dental structure. Moreover, a 3D-printed transparent orthodontic device can be produced which can be restored to the original shape thereof even when deformed from use.

The present invention pertains to a photocurable composition for a 3D printer for producing a transparent orthodontic device. A photocurable composition for a 3D printer can be provided, which has excellent physical properties such as thermal properties, strength, elastic modulus, and tensile elongation, and when used in a patient-customized transparent orthodontic device, the orthodontic device can reduce the pain felt by patients and can enhance orthodontic correction effectiveness due to being closely fitted to the dental structure. Moreover, a 3D-printed transparent orthodontic device can be produced which can be restored to the original shape thereof even when deformed from use.

A radiation curable ink jet composition includes polymerizable compounds; and a photopolymerization initiator, the polymerizable compounds include a vinyl ether group-containing (meth)acrylate represented by the following general formula (I), a content of the vinyl ether group-containing (meth)acrylate with respect to a total mass of the radiation curable ink jet composition is 15 percent by mass or more, and the photopolymerization initiator includes ethyl (2,4,6-trimethylbenzoyl)phenylphosphinate.

H.sub.2C═CR.sup.1—CO—OR.sup.2—O—CH═CH—R.sup.3  (I)

In the above formula, R.sup.1 represents a hydrogen atom or a methyl group, R.sup.2 represents a divalent organic residue having 2 to 20 carbon atoms, and R.sup.3 represents a hydrogen atom or a monovalent organic residue having 1 to 11 carbon atoms.

A method for producing a foamed body includes: forming a foamed layer precursor including applying a coating liquid onto a base to form a liquid film and applying an ink onto the liquid film by an inkjet method, where the coating liquid contains a foaming agent and an active energy ray curable material having a radical-polymerizable functional group, the active energy ray curable material contains a multifunctional active energy ray curable material having two or more radical-polymerizable functional groups, and the ink contains a foaming accelerator having a radical-polymerizable functional group; and foaming a desired position of the foamed layer precursor by heating to form a foamed layer. A functional group equivalent of the radical-polymerizable functional group in the foaming accelerator is greater than a functional group equivalent of the radical-polymerizable functional group in the active energy ray curable material.

A method for producing a foamed body includes: forming a foamed layer precursor including applying a coating liquid onto a base to form a liquid film and applying an ink onto the liquid film by an inkjet method, where the coating liquid contains a foaming agent and an active energy ray curable material having a radical-polymerizable functional group, the active energy ray curable material contains a multifunctional active energy ray curable material having two or more radical-polymerizable functional groups, and the ink contains a foaming accelerator having a radical-polymerizable functional group; and foaming a desired position of the foamed layer precursor by heating to form a foamed layer. A functional group equivalent of the radical-polymerizable functional group in the foaming accelerator is greater than a functional group equivalent of the radical-polymerizable functional group in the active energy ray curable material.

A radiation curable ink jet composition includes polymerizable compounds and a photopolymerization initiator, the polymerizable compounds include a monofunctional monomer, a content of the monofunctional monomer with respect to a total mass of the polymerizable compounds is 90 percent by mass or more, and the photopolymerization initiator includes ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate.

A radiation curable ink jet composition includes polymerizable compounds and a photopolymerization initiator, the polymerizable compounds include a monofunctional monomer, a content of the monofunctional monomer with respect to a total mass of the polymerizable compounds is 90 percent by mass or more, and the photopolymerization initiator includes ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate.

There is provided an ultraviolet ray irradiating apparatus configured to cure an ultraviolet-curable ink discharged to an object, by a discharging head which is configured to move in a main scanning direction, in a state that the ultraviolet ray irradiating apparatus is moved in the main scanning direction. The ultraviolet ray irradiating apparatus includes a plurality of light emitting chips configured to emit an ultraviolet ray, the plurality of light emitting chips being arranged side by side with a first pitch in the main scanning direction and being arranged side by side with a second pitch smaller than the first pitch in a sub scanning direction orthogonal to the main scanning direction.