Abstract: The invention provides an epoxy compound A represented by the following formula (1): in the formula (1), Ar's each independently represent a structure having an unsubstituted or substituted aromatic ring; R1 and R2 each independently represent a hydrogen atom or an alkyl group having 1 or 2 carbon atoms; R3 to R8 represent a hydroxy group, a glycidyl ether group and/or a 2-methylglycidyl ether group, and at least one of R3 to R8 is a glycidyl ether group or a 2-methylglycidyl ether group; R9 to R12 represent a hydroxy group or a methyl group; n is an integer of 11 to 16; and m, p1, p2, and q are average values of repetition, m is 0.5 to 10, p1 and p2 are each independently 0 to 5, and q is 0.5 to 5 (provided that each repeating unit present in the repeating units may be the same or different).

Abstract: The present invention provides an oxazine compound having a specific structure, which contains a group having an aromatic ring structure and a plurality of specified carbon-carbon triple bond structure. The present invention further provides a composition containing the oxazine compound having a specific structure of the present invention, a cured product containing the composition, and a laminate having a layer of the cured product. The present invention further still provides a composition for a heat-resistant material and a composition for an electronic material, which contain the composition containing the oxazine compound of the present invention.

Abstract: An object of the invention is to provide a composition having excellent heat resistance and excellent adhesiveness. Moreover, another object is to provide a cured product obtained by curing the composition and a laminate containing the cured product. Furthermore, another object is to provide a heat-resistant material, a heat-resistant member, an electronic material and an electronic member each containing the composition. The objects are achieved by providing a composition including: a (meth)allyl group-containing maleimide compound having a structure having one or more benzene rings, one or more groups having a (meth)allyl group and one or more groups having a maleimide group; and a hydroxy group-containing maleimide compound having a structure having one or more benzene rings, one or more groups having a hydroxy group and one or more maleimide groups.

Abstract: A conveyor belt includes core layers made of fabric disposed between an upper cover rubber and a lower cover rubber. At least one core layer has a strength in the belt width direction ranging from 30% to 70% of a strength in the belt longitudinal direction.

Abstract: The invention provides an epoxy compound A represented by the following formula (1): in the formula (1), Ar's each independently represent a structure having an unsubstituted or substituted aromatic ring; R1 and R2 each independently represent a hydrogen atom or an alkyl group having 1 or 2 carbon atoms; R3 to R8 represent a hydroxy group, a glycidyl ether group and/or a 2-methylglycidyl ether group, and at least one of R3 to R8 is a glycidyl ether group or a 2-methylglycidyl ether group; R9 to R12 represent a hydroxy group or a methyl group; n is an integer of 11 to 16; and m, p1, p2, and q are average values of repetition, m is 0.5 to 10, p1 and p2 are each independently 0 to 5, and q is 0.5 to 5 (provided that each repeating unit present in the repeating units may be the same or different).

Abstract: An object of the invention is to provide a composition having excellent heat resistance and excellent adhesiveness. Moreover, another object is to provide a cured product obtained by curing the composition and a laminate containing the cured product. Furthermore, another object is to provide a heat-resistant material, a heat-resistant member, an electronic material and an electronic member each containing the composition. The objects are achieved by providing a composition including: a (meth)allyl group-containing maleimide compound having a structure having one or more benzene rings, one or more groups having a (meth)allyl group and one or more groups having a maleimide group; and a hydroxy group-containing maleimide compound having a structure having one or more benzene rings, one or more groups having a hydroxy group and one or more maleimide groups.

Abstract: A conveyor belt includes an upper cover rubber and a lower cover rubber disposed above and below a core layer; and a protective fiber layer made from high strength fiber disposed at least in a central portion of the upper cover rubber in a belt width direction and extending continuously in a belt longitudinal direction; an elastic modulus E of the protective fiber layer in the belt longitudinal direction being a low elastic modulus E1 equal to or less than a predetermined value when a tension in the belt longitudinal direction acting on the conveyor belt is equal to or less than a setting tension Ts, and being a high elastic modulus E2 higher than the low elastic modulus E1 when a predetermined high tension higher than the setting tension Ts is acting on the conveyor belt.

Abstract: The present invention provides an oxazine compound having a specific structure, which contains a group having an aromatic ring structure and a plurality of specified carbon-carbon triple bond structure. The present invention further provides a composition containing the oxazine compound having a specific structure of the present invention, a cured product containing the composition, and a laminate having a layer of the cured product. The present invention further still provides a composition for a heat-resistant material and a composition for an electronic material, which contain the composition containing the oxazine compound of the present invention.

Abstract: A conveyor belt includes core layers made of fabric disposed between an upper cover rubber and a lower cover rubber. At least one core layer has a strength in the belt width direction ranging from 30% to 70% of a strength in the belt longitudinal direction.

Abstract: A conveyor belt includes an upper cover rubber and a lower cover rubber disposed above and below a core layer; and a protective fiber layer made from high strength fiber disposed at least in a central portion of the upper cover rubber in a belt width direction and extending continuously in a belt longitudinal direction; an elastic modulus E of the protective fiber layer in the belt longitudinal direction being a low elastic modulus E1 equal to or less than a predetermined value when a tension in the belt longitudinal direction acting on the conveyor belt is equal to or less than a setting tension Ts, and being a high elastic modulus E2 higher than the low elastic modulus E1 when a predetermined high tension higher than the setting tension Ts is acting on the conveyor belt.

Abstract: The present invention provides an active ester resin containing a phosphorus atom capable of providing a cured product having all of flame retardancy, heat resistance, and dielectric characteristics, an epoxy resin composition containing the same as a curing agent, a cured product thereof, a prepreg, a circuit board, and a build-up film. The active ester resin containing a phosphorus atom has Structure (I) in which a structural unit (?) in which a plurality of aromatic nuclei (X) are connected through an alicyclic hydrocarbon group is connected with another structural unit (?) through an arylene dicarbonyloxy group, and, at least one of the aromatic nuclei (X) present in the resin has a structural site (Y) represented by any one of the following Structural Formulas (y1) to (y4) as a substituent on the aromatic nucleus.

Abstract: The present invention provides an active ester resin containing a phosphorus atom capable of providing a cured product having all of flame retardancy, heat resistance, and dielectric characteristics, an epoxy resin composition containing the same as a curing agent, a cured product thereof, a prepreg, a circuit board, and a build-up film. The active ester resin containing a phosphorus atom has Structure (I) in which a structural unit (?) in which a plurality of aromatic nuclei (X) are connected through an alicyclic hydrocarbon group is connected with another structural unit (?) through an arylene dicarbonyloxy group, and, at least one of the aromatic nuclei (X) present in the resin has a structural site (Y) represented by any one of the following Structural Formulas (y1) to (y4) as a substituent on the aromatic nucleus.

Abstract: A cured product exhibits good heat resistance and flame retardancy as well as low dielectric constant and low loss tangent. A phosphorus-containing compound (i) obtained by a reaction between an aromatic aldehyde (a1) having an alkoxy group as a substituent on a nucleus and an organic phosphorus compound (a2) having a P—H group or a P—OH group in a molecular structure is reacted with a phenolic substance (a3) to obtain a phosphorus-containing phenolic substance (A1). Then the phosphorus-containing phenolic substance (A1) is reacted with an aromatic dicarboxylic acid or an anhydride or dihalide of an aromatic dicarboxylic acid or a C2-6 saturated dicarboxylic acid or an anhydride or dihalide of a C2-6 saturated dicarboxylic acid (A2) so that all or some of hydroxyl groups of the phenolic substance (A1) form ester bonds.

Abstract: A cured product exhibits good heat resistance and flame retardancy as well as low dielectric constant and low loss tangent. A phosphorus-containing compound (i) obtained by a reaction between an aromatic aldehyde (a1) having an alkoxy group as a substituent on a nucleus and an organic phosphorus compound (a2) having a P—H group or a P—OH group in a molecular structure is reacted with a phenolic substance (a3) to obtain a phosphorus-containing phenolic substance (A1). Then the phosphorus-containing phenolic substance (A1) is reacted with an aromatic dicarboxylic acid or an anhydride or dihalide of an aromatic dicarboxylic acid or a C2-6 saturated dicarboxylic acid or an anhydride or dihalide of a C2-6 saturated dicarboxylic acid (A2) so that all or some of hydroxyl groups of the phenolic substance (A1) form ester bonds.

Abstract: A low dielectric constant, a low dielectric loss tangent, and heat resistance are achieved. An active ester resin that has a resin structure produced by reacting a polyfunctional phenolic compound (a1) with a monofunctional aromatic carboxylic acid or its chloride (a2) and an aromatic dicarboxylic acid or its chloride (a3). The polyfunctional phenolic compound (a1) is represented by structural formula (1) below: (where Ar represents a benzene ring, a naphthalene ring, a benzene ring nuclear-substituted by an alkyl group having 1 to 4 carbon atoms, or a naphthalene ring nuclear-substituted by an alkyl group having 1 to 4 carbon atoms, X represents a methylene group, a divalent cyclic aliphatic hydrocarbon group, a phenylene dimethylene group, or a biphenylene-dimethylene group, and n represents the number of repeating units and the average thereof is in a range of 0.5 to 10).

Abstract: A low dielectric constant, a low dielectric loss tangent, and heat resistance are achieved. An active ester resin that has a resin structure produced by reacting a polyfunctional phenolic compound (a1) with a monofunctional aromatic carboxylic acid or its chloride (a2) and an aromatic dicarboxylic acid or its chloride (a3). The polyfunctional phenolic compound (a1) is represented by structural formula (1) below: (where Ar represents a benzene ring, a naphthalene ring, a benzene ring nuclear-substituted by an alkyl group having 1 to 4 carbon atoms, or a naphthalene ring nuclear-substituted by an alkyl group having 1 to 4 carbon atoms, X represents a methylene group, a divalent cyclic aliphatic hydrocarbon group, a phenylene dimethylene group, or a biphenylene-dimethylene group, and n represents the number of repeating units and the average thereof is in a range of 0.5 to 10).

Abstract: A thermosetting resin composition contains an active ester resin (A) and an epoxy resin (B) as essential components, the active ester resin (A) having a resin structure which includes a polyaryleneoxy structure (I) and in which aromatic carbon atoms in a plurality of the polyaryleneoxy structures (I) are linked through a structural site (II) represented by a structural formula 1 (wherein Ar represents a phenylene group, a phenylene group nuclear-substituted by 1 to 3 alkyl groups each having 1 to 4 carbon atoms, a naphthylene group, or a naphthylene group nuclear-substituted by 1 to 3 alkyl groups each having 1 to 4 carbon atoms).

Abstract: A thermosetting resin composition contains an active ester resin (A) and an epoxy resin (B) as essential components, the active ester resin (A) having a resin structure which includes a polyaryleneoxy structure (I) and in which aromatic carbon atoms in a plurality of the polyaryleneoxy structures (I) are linked through a structural site (II) represented by a structural formula 1 (wherein Ar represents a phenylene group, a phenylene group nuclear-substituted by 1 to 3 alkyl groups each having 1 to 4 carbon atoms, a naphthylene group, or a naphthylene group nuclear-substituted by 1 to 3 alkyl groups each having 1 to 4 carbon atoms).

Abstract: A method of making a magnetic head wherein a metal material is sandwiched between non-magnetic substrates, including the steps of: forming a magnetic metal material at least on one side of a non-magnetic substrate; forming by sputtering a crystallization glass layer at least on one side of a compound substrate prepared by forming an anti-diffusion film on the magnetic metal material; then heat-treating in an oxygen containing atmosphere the compound substrate on which the crystallization glass has been formed; further laminating together a number of the aforesaid compound substrates under pressure and then processing (such as by cutting, grinding, and heat-treating) the laminate.

Abstract: A head core includes a pair of core parts made of a magnetic metallic material and bonded together by (1) a gap material which is a low-melting-point crystallized glass which serves as the bonding material and (2) non-magnetic material layers provided between the glass and the gap surfaces of the core parts. The non-magnetic material layers effectively prevent reaction between the low-melting-point crystallized glass and the metallic magnetic material of the core during the bonding heat treatment. The strength of the magnetic gap, as well as dimensional precision of the same, is enhanced as compared with the conventional arrangement of the same gap size in which bonding is accomplished by a low-melting-point non-crystallizable glass, even when the bonding is executed at the same temperature. The invention remarkably improves magnetic head production yields and reliability.