Abstract: To provide: a solvent used for synthesizing a synthetic resin such as a polyimide resin and a polyurethane resin, the solvent capable of synthesizing a polymer having a high molecular weight in a short time, causing no clouding of a reaction solution during and after reaction, and having high transparency and storage stability; and a method for producing the synthetic resin using the solvent. A solvent (C) for resin synthesis, containing: 10 to 99.9999 mass % of an amide-based solvent (A); and 0.0001 to 5 mass % of a reaction accelerator (B), in which the reaction accelerator (B) is an aliphatic or aromatic tertiary amine compound having one or more tertiary amino groups in a molecule of the reaction accelerator (B).

Abstract: An active energy ray-curable resin composition for three-dimensional molding support materials is provided and includes 0.1 to 90% by mass of a non-polymerizable compound (A) in which inorganic groups/organic groups (I/O value) equals 0.4 to 1.8, and 10 to 99.9% by mass of a polymerizable compound (B) in which inorganic groups/organic groups (I/O value) equals 0.8 to 3.0. By using the active energy ray-curable resin composition, an ink for a support material having well-balanced inorganicity and organicity is obtained, and by using the ink, the support material is easily removed from a roughly molded product without corrosion of ink tanks, ink ejection heads, and similar objects, and a large-sized and highly accurate three-dimensional molded product is obtained.

Abstract: The present application provides a photopolymerization initiator having one or more ethylenic unsaturated bonds and one or more photopolymerization initiating functional groups in the molecule has been found. One or more kinds selected from an acrylamide group, an acrylate group, a vinyl group, an allyl group, a maleimide group, and the like can be suitably used as the ethylenic unsaturated bond, and a benzophenone compound having a specific structure can be suitably used as the photopolymerization initiating functional group.

Abstract: The present application provides a photopolymerization initiator having one or more ethylenic unsaturated bonds and one or more photopolymerization initiating functional groups in the molecule has been found. One or more kinds selected from an acrylamide group, an acrylate group, a vinyl group, an allyl group, a maleimide group, and the like can be suitably used as the ethylenic unsaturated bond, and a benzophenone compound having a specific structure can be suitably used as the photopolymerization initiating functional group.

Abstract: An active energy ray-curable resin composition for three-dimensional molding support materials is provided and includes 0.1 to 90% by mass of a non-polymerizable compound (A) in which inorganic groups/organic groups (I/O value) equals 0.4 to 1.8, and 10 to 99.9% by mass of a polymerizable compound (B) in which inorganic groups/organic groups (I/O value) equals 0.8 to 3.0. By using the active energy ray-curable resin composition, an ink for a support material having well-balanced inorganicity and organicity is obtained, and by using the ink, the support material is easily removed from a roughly molded product without corrosion of ink tanks, ink ejection heads, and similar objects, and a large-sized and highly accurate three-dimensional molded product is obtained.

Abstract: An object is to provide a (meth)acrylamide based urethane oligomer which has excellent compatibility with organic solvents and general purpose acrylic monomers and oligomers, a high curing property with an active energy ray, and a low curing shrinkage property, and to provide an active energy ray curable resin composition containing the same which has an excellent adhesion property, moisture resistance, surface curing property, and also a low curing shrinkage property, and a molded article of the same. By using a (meth)acrylamide based urethane oligomer characterized by having a (meth)acrylamide group at the end or in side chain thereof and a cure shrinkage rate of 5% or less, it is possible to prepare a urethane oligomer having high curing property and excellent compatibility with organic solvents and general purpose acrylic monomers and oligomers, and an active energy ray curable resin composition containing the same and having excellent adhesion property can be prepared.

Abstract: An object is to provide a (meth)acrylamide based urethane oligomer which has excellent compatibility with organic solvents and general purpose acrylic monomers and oligomers, a high curing property with an active energy ray, and a low curing shrinkage property, and to provide an active energy ray curable resin composition containing the same which has an excellent adhesion property, moisture resistance, surface curing property, and also a low curing shrinkage property, and a molded article of the same. By using a (meth)acrylamide based urethane oligomer characterized by having a (meth)acrylamide group at the end or in side chain thereof and a cure shrinkage rate of 5% or less, it is possible to prepare a urethane oligomer having high curing property and excellent compatibility with organic solvents and general purpose acrylic monomers and oligomers, and an active energy ray curable resin composition containing the same and having excellent adhesion property can be prepared.

Abstract: [Problem] An problem of the present invention is to provide to a (meth)acrylamide-based urethane oligomer which has excellent compatibility with organic solvents, general purpose acrylic monomers and oligomers, and a high curing speed to active energy rays, and to provide an active energy ray curable resin composition which contains the urethane oligomer, has excellent adhesion, moisture resistance and surface curability, and has low curing shrinkage, and a formed product thereof [Means for Solution] By using a (meth)acrylamide-based urethane oligomer of the present invention which has a carbonate skeleton, a diene-based skeleton or a hydrogenated diene-based skeleton in the molecule, one or more (meth)acrylamide groups and a component having a molecular weight of less than 1,000 (excluding a (meth)acrylamide compound (A) having a hydroxyl group) at a content of 5% by weight or less, it is possible to obtain a urethane oligomer which has excellent compatibility with organic solvents, general purpose acrylic m

Abstract: An problem of the present invention is to provide to a (meth)acrylamide-based urethane oligomer which has excellent compatibility with organic solvents, general purpose acrylic monomers and oligomers, and a high curing speed to active energy rays, and to provide an active energy ray curable resin composition which contains the urethane oligomer, has excellent adhesion, moisture resistance and surface curability, and has low curing shrinkage, and a formed product thereof [Means for Solution] By using a (meth)acrylamide-based urethane oligomer of the present invention which has a carbonate skeleton, a diene-based skeleton or a hydrogenated diene-based skeleton in the molecule, one or more (meth)acrylamide groups and a component having a molecular weight of less than 1,000 (excluding a (meth)acrylamide compound (A) having a hydroxyl group) at a content of 5% by weight or less, it is possible to obtain a urethane oligomer which has excellent compatibility with organic solvents, general purpose acrylic monomers an