Abstract: Provided are an active energy ray-curable composition which has a low viscosity suitable for coating and also exhibits a high refractive index in terms of a cured product thereof, a cured product thereof, and a plastic lens. The active energy ray-curable composition contains a phenylbenzyl (meth)acrylate (A) and a bicarbazole compound (B) represented by the following structural formula (1) (in the formula, X1 and X2 each independently represent a photopolymerizable functional group, a structural moiety having a photopolymerizable functional group, or a hydrogen atom, provided that at least one of X1 and X2 represents a photopolymerizable functional group or a structural moiety having a photopolymerizable functional group; and R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a bromine atom, or a chlorine atom).

Abstract: A urethane (meth)acrylate resin wherein the viscosity of the resin is low, the formability into a sheet-formed product, in particular, an optical sheet provided with fine uneven shapes on the surface is excellent, and a high refractive index can be realized, a curable resin composition including the urethane (meth)acrylate resin as an indispensable component, a cured product thereof, and a plastic lens are provided. A urethane (meth)acrylate resin produced by reacting aromatic diisocyanate compound (a), bisphenol-ethylene oxide adduct diol (b) having at least three aromatic ring or alicyclic structures in the molecule, and hydroxy-containing (meth)acrylate compound (c), which are indispensable raw material components, a curable resin composition containing the urethane (meth)acrylate resin as a primary component, and a cured product thereof.

Abstract: Provided are an active energy ray-curable composition which has a viscosity suitable for coating and also has a super high refractive index at a level higher than ever, a cured product thereof, and a plastic lens. The active energy ray-curable composition contains zirconium oxide nanoparticles (A) and a bicarbazole compound (B) represented by the following structural formula (1) (in the formula, X1 and X2 each independently represent a photopolymerizable functional group, a structural moiety having a photopolymerizable functional group, or a hydrogen atom, provided that at least one of X1 and X2 represents a photopolymerizable functional group or a structural moiety having a photopolymerizable functional group; and R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a bromine atom, or a chlorine atom).

Abstract: There is provided a curable composition, which forms a cured product with high light transmittance, a high refractive index, and high scratch resistance, a cured product thereof, and an optical member. A curable composition contains zirconium oxide nanoparticles, a dispersant, and a (meth)acrylate compound. The dispersant has an acid value in the range of 100 to 300 mgKOH/g. The (meth)acrylate compound contains a (meth)acrylate compound having a poly(alkylene oxide) structure.

Abstract: Provided are a cured material having a high refractive index for an optical member obtained by preparing a stable dispersion with a small amount of dispersant, and a process for producing dispersion of fine inorganic particles which is capable of drastically shortening the dispersion process time without causing overdispersion under the conditions of high solid concentration and without using media having a small particle size, which are very expensive and for which available dispersing machines are limited. Provided are a process for producing dispersion of fine inorganic particles using a media type wet dispersing machine, which includes supplying the following (A) to (D) to the wet dispersing machine, provided that (D) is supplied last to the wet dispersing machine: (A) Zirconium oxide nanoparticle, (B) Silane coupling agent, (C) Dispersion medium, and (D) Dispersant; a curable composition containing a dispersion obtained by the producing process; and a cured material obtained therefrom.

Abstract: Provided are an active energy ray-curable composition which has a low viscosity suitable for coating and also exhibits a high refractive index in terms of a cured product thereof, a cured product thereof, and a plastic lens. The active energy ray-curable composition contains a phenylbenzyl (meth)acrylate (A) and a bicarbazole compound (B) represented by the following structural formula (1) (in the formula, X1 and X2 each independently represent a photopolymerizable functional group, a structural moiety having a photopolymerizable functional group, or a hydrogen atom, provided that at least one of X1 and X2 represents a photopolymerizable functional group or a structural moiety having a photopolymerizable functional group; and R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a bromine atom, or a chlorine atom).

Abstract: Provided are an active energy ray-curable composition which has a viscosity suitable for coating and also has a super high refractive index at a level higher than ever, a cured product thereof, and a plastic lens. The active energy ray-curable composition contains zirconium oxide nanoparticles (A) and a bicarbazole compound (B) represented by the following structural formula (1) (in the formula, X1 and X2 each independently represent a photopolymerizable functional group, a structural moiety having a photopolymerizable functional group, or a hydrogen atom, provided that at least one of X1 and X2 represents a photopolymerizable functional group or a structural moiety having a photopolymerizable functional group; and R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a bromine atom, or a chlorine atom).

Abstract: Provided is a photocurable resin composition that has a low viscosity and is capable of yielding a high refractive index. Specifically, a urethane (meth)acrylate resin (A) obtained by a reaction of an aromatic diisocyanate compound (a), a polyol compound (b), and a hydroxyl-group-containing (meth)acrylate compound (c) as essential raw material components is used. The urethane (meth)acrylate resin (A) contains a structural moiety (a-1) represented by structural formula (1) below: (where R1 represents a hydrogen atom or a methyl group) and a structural moiety (a-2) represented by structural formula (2) below: (where R1, R2, R3, X1, and X2 each independently represent a hydrogen atom or a methyl group) at a (a-1)/(a-2) molar ratio of 45/55 to 60/40. The polyol compound (b) has an aromatic hydrocarbon skeleton.

Abstract: A urethane (meth)acrylate resin wherein the viscosity of the resin is low, the formability into a sheet-formed product, in particular, an optical sheet provided with fine uneven shapes on the surface is excellent, and a high refractive index can be realized, a curable resin composition including the urethane (meth)acrylate resin as an indispensable component, a cured product thereof, and a plastic lens are provided. A urethane (meth)acrylate resin produced by reacting aromatic diisocyanate compound (a), bisphenol-ethylene oxide adduct diol (b) having at least three aromatic ring or alicyclic structures in the molecule, and hydroxy-containing (meth)acrylate compound (c), which are indispensable raw material components, a curable resin composition containing the urethane (meth)acrylate resin as a primary component, and a cured product thereof.

Abstract: There is provided a curable composition, which forms a cured product with high light transmittance, a high refractive index, and high scratch resistance, a cured product thereof, and an optical member. A curable composition contains zirconium oxide nanoparticles, a dispersant, and a (meth)acrylate compound. The dispersant has an acid value in the range of 100 to 300 mgKOH/g. The (meth)acrylate compound contains a (meth)acrylate compound having a poly(alkylene oxide) structure.

Abstract: Provided are a cured material having a high refractive index for an optical member obtained by preparing a stable dispersion with a small amount of dispersant, and a process for producing dispersion of fine inorganic particles which is capable of drastically shortening the dispersion process time without causing overdispersion under the conditions of high solid concentration and without using media having a small particle size, which are very expensive and for which available dispersing machines are limited. Provided are a process for producing dispersion of fine inorganic particles using a media type wet dispersing machine, which includes supplying the following (A) to (D) to the wet dispersing machine, provided that (D) is supplied last to the wet dispersing machine: (A) Zirconium oxide nanoparticle, (B) Silane coupling agent, (C) Dispersion medium, and (D) Dispersant; a curable composition containing a dispersion obtained by the producing process; and a cured material obtained therefrom.

Abstract: Provided is a photocurable resin composition that has a low viscosity and is capable of yielding a high refractive index. Specifically, a urethane (meth)acrylate resin (A) obtained by a reaction of an aromatic diisocyanate compound (a), a polyol compound (b), and a hydroxyl-group-containing (meth)acrylate compound (c) as essential raw material components is used. The urethane (meth)acrylate resin (A) contains a structural moiety (a-1) represented by structural formula (1) below: (where R1 represents a hydrogen atom or a methyl group) and a structural moiety (a-2) represented by structural formula (2) below: (where R1, R2, R3, X1, and X2 each independently represent a hydrogen atom or a methyl group) at a (a-1)/(a-2) molar ratio of 45/55 to 60/40. The polyol compound (b) has an aromatic hydrocarbon skeleton.