Abstract: A rubber composition capable of forming a conveyor belt. The rubber composition for a conveyor belt contains: rubber components including natural rubber and butadiene rubber; a vulcanizing agent; a vulcanization accelerator; carbon black; chlorinated paraffin; and antimony trioxide. A mass ratio of content of the natural rubber to content of the butadiene rubber (natural rubber content:butadiene rubber content) is 25:75 to 45:55.

Abstract: Disclosed is a photocurable elastomer composition that exhibits, when cured, excellent flexibility and barrier properties and has low compression set. The photocurable elastomer composition may comprise components (A) to (D) such that the mass ratio of the component (A) to the component (B) ((A):(B)) is from 25:75 to 75:25, and that the content of the component (C) is 50 mass % or less based on the total content of the components (A), (B), and (C).

Abstract: Provided is a rubber composition capable of forming a conveyor belt having an excellent low loss property, while also retaining high strength and high flame retardance as a rubber article. The rubber composition for a conveyor belt contains: rubber components including natural rubber and butadiene rubber; a vulcanizing agent; a vulcanization accelerator; carbon black; chlorinated paraffin; and antimony trioxide. A mass ratio of content of the natural rubber to content of the butadiene rubber (natural rubber content:butadiene rubber content) is 25:75 to 45:55.

Abstract: An optical element formed by stacking each of two resin layers on a glass substrate, wherein when the second resin layer of the two resin layers counting from the glass substrate is formed, an external circumferential part of the second resin layer is formed so as to be located inward of the outer circumferential part of the first resin layer, which is located closer to the glass substrate than the second resin layer.

Abstract: A photocurable elastomer composition comprising: (A) a liquid polymer having a number average molecular weight of 5,000 or more, and mainly containing —[CH2C(CH3)2]— units; (B) a (meth)acrylate monomer; and (C) a photo polymerization initiator, the mass ratio ((A):(B)) between the component (A) and the component (B) being 10:90 to 39:61.

Abstract: Provided is an energy ray-curable elastomer composition which can increase the inter-crosslinking point molecular weight without changing the kind of an energy ray-curable compound before cured and which provides an oligomer-cured substance having a braking elongation compatible with a processability, to be specific, an energy ray-curable elastomer composition containing (A) an energy ray-curable compound having a (meth)acryloyl group and (B) a polythiol compound having 2 to 6 mercapto groups in a molecule, wherein a functional group number ratio of the (meth)acryloyl group in the above composition to the mercapto group in the component (B) is 100:0.1 to 100:5n (n is the number of the mercapto group in a molecule of the polythiol compound).

Abstract: A photocurable elastomer composition comprising: (A) a liquid polymer having a number average molecular weight of 5,000 or more, and mainly containing —[CH2C(CH3)2]— units; (B) a (meth)acrylate monomer; and (C) a photo polymerization initiator, the mass ratio ((A):(B)) between the component (A) and the component (B) being 10:90 to 39:61.

Abstract: Disclosed is a photocurable elastomer composition that exhibits, when cured, excellent flexibility and barrier properties and has low compression set. The photocurable elastomer composition may comprise components (A) to (D) such that the mass ratio of the component (A) to the component (B) ((A):(B)) is from 25:75 to 75:25, and that the content of the component (C) is 50 mass % or less based on the total content of the components (A), (B), and (C).

Abstract: An achromatic lens system is provided with a cemented resin lens having positive refractive power constructed by a resin lens L11 having positive refractive power cemented with a resin lens L12 having negative refractive power, and a close-contact multi-layer type diffractive optical element L11E, the diffractive optical element L11E being disposed to an image side of the cemented resin lens, the diffractive optical element L11E being constructed by cementing two diffractive element members DE11, DE12 each made of different optical materials with each other, and the cemented surface thereof being a diffractive optical surface Gf on which grooves of a diffraction grating are formed, there by being lightweight and easily manufactured, capable of excellently correcting chromatic aberration and spherical aberration at the same time.

Abstract: A method for manufacturing an optical element (1) formed by stacking each of two resin layers (4, 6) on a glass substrate (2), wherein when the second resin layer (6) of the two resin layers (4, 6) counting from the glass substrate (2) is formed, an external circumferential part of the second resin layer (6) is formed so as to be located inward of the outer circumferential part, of the first resin layer (4), which is located closer to the glass substrate (2) than the second resin layer (6).

Abstract: Provided are a photocurable resin composition which has a short time required for curing to make it possible to enhance the productivity and which can provide a light-emitting element sealant having an excellent heat resistance and an excellent optical transparency and a light-emitting element sealant prepared by using the above photocurable resin composition. To be specific, provided are a photocurable resin composition comprising 100 parts by mass of an end-modified hydrogenated styrene-butadiene rubber (A) and 0.1 to 13 parts by mass of an ?-hydroxyalkylphenone base photopolymerization initiator and/or an acylphosphine oxide base photopolymerization initiator and a light-emitting element sealant prepared by using the above photocurable resin composition (B).

Abstract: An energy ray-curable elastomer composition, which comprises an energy ray-curable compound (A) having a (meth)acryloyl group, a polythiol compound (B) having 2 to 6 mercapto groups per molecule, and a polyfunctional (meth)acrylate (C), characterized in that the ratio of the number of (meth)acryloyl functional groups in component (A) to the number of mercapto functional groups in component (B) is 100:0.1-100:5n (wherein n represents the number of mercapto groups per molecule of the polythiol compound), and component (C) is used at a ratio of 1-8 parts by mass per 100 parts by mass of component (A). Thus, an energy ray-curable elastomer composition, which can achieve both high breaking elongation and good processability and shows good compression set, can be provided.

Abstract: Provided is an energy ray-curable elastomer composition which can increase the inter-crosslinking point molecular weight without changing the kind of an energy ray-curable compound before cured and which provides an oligomer-cured substance having a braking elongation compatible with a processability, to be specific, an energy ray-curable elastomer composition containing (A) an energy ray-curable compound having a (meth)acryloyl group and (B) a polythiol compound having 2 to 6 mercapto groups in a molecule, wherein a functional group number ratio of the (meth)acryloyl group in the above composition to the mercapto group in the component (B) is 100:0.1 to 100:5n (n is the number of the mercapto group in a molecule of the polythiol compound).

Abstract: Provided are a gasket-forming material for a hard disk device providing a gasket which can improve a reworking property of a cover plate and a base plate in a hard disk device and a gasket prepared by using the above material. They are a gasket-forming material for a hard disk device comprising (A) an energy ray-curable urethane liquid oligomer having a polymerizable unsaturated group and (B) a monofunctional (meth)acryl base monomer providing a cured matter having a glass transition temperature (Tg) of ?70 to 20° C. and a gasket for a hard disk device comprising a cured matter prepared by curing the above material by irradiating with an energy ray.

Abstract: An achromatic lens system is provided with a cemented resin lens having positive refractive power constructed by a resin lens L11 having positive refractive power cemented with a resin lens L12 having negative refractive power, and a close-contact multi-layer type diffractive optical element L11E, the diffractive optical element L11E being disposed to an image side of the cemented resin lens, the diffractive optical element L11E being constructed by cementing two diffractive element members DE11, DE12 each made of different optical materials with each other, and the cemented surface thereof being a diffractive optical surface Gf on which grooves of a diffraction grating are formed, there by being lightweight and easily manufactured, capable of excellently correcting chromatic aberration and spherical aberration at the same time.

Abstract: An achromatic lens system is provided with a cemented resin lens having positive refractive power constructed by a resin lens L11 having positive refractive power cemented with a resin lens L12 having negative refractive power, and a close-contact multi-layer type diffractive optical element L11E, the diffractive optical element L11E being disposed to an image side of the cemented resin lens, the diffractive optical element L11E being constructed by cementing two diffractive element members DE11, DE12 each made of different optical materials with each other, and the cemented surface thereof being a diffractive optical surface Gf on which grooves of a diffraction grating are formed, there by being lightweight and easily manufactured, capable of excellently correcting chromatic aberration and spherical aberration at the same time.

Abstract: A sealing material which comprises (A) an unsaturated group-containing ester-type urethane oligomer which is an energy ray-curable liquid resin and (B) a compound having at least one carbodiimide group in the molecule in an amount of 0.01 to 10 parts by mass based on 100 parts by mass of the component (A) and which is excellent in moist heat durability, can retain low moisture permeability, is excellent in adhesion to a material to be jointed and can form a highly precise extrusion shape; a process for production of a scaling material excellent in long-term storage stability; a scaling material produced by the process; a gasket using a sealing material having the above-mentioned properties. A cured product of the sealing material has a reduced surface adhesion property, enables the easy removal of an HDD cover, and consequently is improved in durability against an external force produced at the time of reuse.

Abstract: An achromatic lens system is provided with a cemented resin lens having positive refractive power constructed by a resin lens L11 having positive refractive power cemented with a resin lens L12 having negative refractive power, and a close-contact multi-layer type diffractive optical element L11E, the diffractive optical element L11E being disposed to an image side of the cemented resin lens, the diffractive optical element L11E being constructed by cementing two diffractive element members DE11, DE12 each made of different optical materials with each other, and the cemented surface thereof being a diffractive optical surface Gf on which grooves of a diffraction grating are formed, there by being lightweight and easily manufactured, capable of excellently correcting chromatic aberration and spherical aberration at the same time.