Abstract: A water-dispersible polyisocyanate contains an isocyanate group and a sulfone group. The water-dispersible polyisocyanate contains a reaction product of a polyisocyanate component and a hydrophilic active hydrogen component. The polyisocyanate component contains a first polyisocyanate containing pentamethylene diisocyanate and a second polyisocyanate containing polyisocyanate having 6 or more carbon atoms. The hydrophilic active hydrogen component contains a sulfone group-containing active hydrogen compound. The first polyisocyanate is contained in an amount of 40% by mass or more and 90% by mass or less relative to the total amount of the first polyisocyanate and the second polyisocyanate.

Abstract: A water-dispersible polyisocyanate contains an isocyanate group and a sulfone group. The water-dispersible polyisocyanate contains a reaction product of a polyisocyanate component and a hydrophilic active hydrogen component. The polyisocyanate component contains a bis(isocyanatomethyl)cyclohexane derivative. The hydrophilic active hydrogen component contains a sulfone group-containing active hydrogen compound. The bis(isocyanatomethyl)cyclohexane derivative contains an allophanate derivative and an isocyanurate derivative. The allophanate derivative is contained in an amount of 25% by mass or more and 75% by mass or less relative to the total amount of the allophanate derivative and the isocyanurate derivative.

Abstract: The method for producing pentamethylene diisocyanate includes a reaction step, in which carbonyl chloride is allowed to react with pentamethylenediamine to produce a reaction mixture containing pentamethylene diisocyanate and a tar component containing a chlorine-containing component; a heating step, in which the reaction mixture is heated; and a purification step, in which the reaction mixture after the heating step is purified to separate the pentamethylene diisocyanate from the tar component, wherein in the heating step, the reaction mixture is heated without removing the tar component from the reaction mixture.

Abstract: The method for producing pentamethylene diisocyanate includes a reaction step, in which carbonyl chloride is allowed to react with pentamethylenediamine to produce a reaction mixture containing pentamethylene diisocyanate and a tar component containing a chlorine-containing component; a heating step, in which the reaction mixture is heated; and a purification step, in which the reaction mixture after the heating step is purified to separate the pentamethylene diisocyanate from the tar component, wherein in the heating step, the reaction mixture is heated without removing the tar component from the reaction mixture.

Abstract: Xylylene dicarbamate contains impurities represented by formulas (1) to (4) below at a ratio of less than 100 ppm as a total amount thereof on a mass basis. (In the above-described formulas (1) to (4), R represents a monovalent hydrocarbon group.).

Abstract: Xylylene dicarbamate contains impurities represented by formulas (1) to (4) below at a ratio of less than 100 ppm as a total amount thereof on a mass basis. (In the above-described formulas (1) to (4), R represents a monovalent hydrocarbon group.

Abstract: Xylylene dicarbamate contains impurities represented by formulas (1) to (4) below at a ratio of less than 100 ppm as a total amount thereof on a mass basis. (In the above-described formulas (1) to (4), R represents a monovalent hydrocarbon group.

Abstract: A method for producing xylylene diisocyanate includes a thermal decomposition step of thermally decomposing xylylene dicarbamate; a first separation step of separating, from the thermal decomposition product obtained in the thermal decomposition step, an isocyanate-containing component containing xylylene diisocyanate as a main component and an alcohol-containing component containing alcohol as a main component and containing xylylene diisocyanate as a subcomponent; a second separation step of separating xylylene dicarbamate and alcohol from the alcohol-containing component obtained in the first separation step; and a returning step of returning xylylene dicarbamate obtained in the second separation step to the thermal decomposition step.

Abstract: A method for producing carbamate including a urea production step; a carbamate-forming step; an ammonia separation step of absorbing the gas with water in the presence of carbonate to produce a gas absorption water, and separating ammonia; an aqueous alcohol solution separation step of separating an aqueous alcohol solution from the gas absorption water; an ammonia/carbon dioxide separation step of separating carbon dioxide gas from the aqueous ammonia solution in the gas absorption water from which the aqueous alcohol solution is separated; an aqueous ammonia solution reusing step of mixing the aqueous ammonia solution and carbonate with the water to be used for production of the gas absorption water.

Abstract: A method for producing xylylene diisocyanate includes a thermal decomposition step of thermally decomposing xylylene dicarbamate; a first separation step of separating, from the thermal decomposition product obtained in the thermal decomposition step, an isocyanate-containing component containing xylylene diisocyanate as a main component and an alcohol-containing component containing alcohol as a main component and containing xylylene diisocyanate as a subcomponent; a second separation step of separating xylylene dicarbamate and alcohol from the alcohol-containing component obtained in the first separation step; and a returning step of returning xylylene dicarbamate obtained in the second separation step to the thermal decomposition step.

Abstract: Xylylene dicarbamate contains impurities represented by formulas (1) to (4) below at a ratio of less than 100 ppm as a total amount thereof on a mass basis. (In the above-described formulas (1) to (4), R represents a monovalent hydrocarbon group.

Abstract: A method for producing carbamate including a urea production step; a carbamate-forming step; an ammonia separation step of absorbing the gas with water in the presence of carbonate to produce a gas absorption water, and separating ammonia; an aqueous alcohol solution separation step of separating an aqueous alcohol solution from the gas absorption water; an ammonia/carbon dioxide separation step of separating carbon dioxide gas from the aqueous ammonia solution in the gas absorption water from which the aqueous alcohol solution is separated; an aqueous ammonia solution reusing step of mixing the aqueous ammonia solution and carbonate with the water to be used for production of the gas absorption water.

Abstract: A method for producing carbamate including a urea production step; a carbamate-forming step; an ammonia separation step of absorbing the gas with water in the presence of carbonate to produce a gas absorption water, and separating ammonia; an aqueous alcohol solution separation step of separating an aqueous alcohol solution from the gas absorption water; an ammonia/carbon dioxide separation step of separating carbon dioxide gas from the aqueous ammonia solution in the gas absorption water from which the aqueous alcohol solution is separated; an aqueous ammonia solution reusing step of mixing the aqueous ammonia solution and carbonate with the water to be used for production of the gas absorption water.

Abstract: A method for producing tolylene diisocyanate includes: mixing a first diaminotoluene containing 2,4-diaminotoluene and 2,6-diaminotoluene at a first isomer ratio and a second diaminotoluene containing 2,4-diaminotoluene and/or 2,6-diaminotoluene at a second isomer ratio that is different from the first isomer ratio so as to prepare mixed diaminotoluene; producing tolylene dicarbamate by reaction of the mixed diaminotoluene, urea and/or N-unsubstituted carbamic acid ester and alcohol; and thermally decomposing the tolylene dicarbamate.

Abstract: A method for producing toluenedicarbamate includes a carbamate production process of producing toluenedicarbamate by reaction between toluenediamine, urea, and/or N-unsubstituted carbamic acid ester, and alcohol; and a benzoyleneurea reduction process of reducing a disubstituted benzoyleneurea and a derivative thereof to 10 mol or less relative to 100 mol of toluenedicarbamate, wherein the disubstituted benzoyleneurea is represented by formula (1) below and has a methyl group and an amino group:

Abstract: A method for producing tolylene diisocyanate includes: mixing a first diaminotoluene containing 2,4-diaminotoluene and 2,6-diaminotoluene at a first isomer ratio and a second diaminotoluene containing 2,4-diaminotoluene and/or 2,6-diaminotoluene at a second isomer ratio that is different from the first isomer ratio so as to prepare mixed diaminotoluene; producing tolylene dicarbamate by reaction of the mixed diaminotoluene, urea and/or N-unsubstituted carbamic acid ester and alcohol; and thermally decomposing the tolylene dicarbamate.

Abstract: A method for producing toluenedicarbamate includes a carbamate production process of producing toluenedicarbamate by reaction between toluenediamine, urea, and/or N-unsubstituted carbamic acid ester, and alcohol; and a benzoyleneurea reduction process of reducing a disubstituted benzoyleneurea and a derivative thereof to 10 mol or less relative to 100 mol of toluenedicarbamate, wherein the disubstituted benzoyleneurea is represented by formula (1) below and has a methyl group and an amino group:

Abstract: A method for producing carbamate including a urea production step; a carbamate-forming step: an ammonia separation step of absorbing the gas with water in the presence of carbonate to produce a gas absorption water, and separating ammonia; an aqueous alcohol solution separation step of separating an aqueous alcohol solution from the gas absorption water; an ammonia/carbon dioxide separation step of separating carbon dioxide gas from the aqueous ammonia solution in the gas absorption water from which the aqueous alcohol solution is separated; an aqueous ammonia solution reusing step of mixing the aqueous ammonia solution and carbonate with the water to be used for production of the gas absorption water.

Abstract: A valve system for an internal combustion engine capable of changing the valve timing and valve lift of the intake and exhaust valves driven by rocker arms and overhead camshafts. A cam support member is pivotally mounted to the engine head and is positioned by a gear segment mounted to the camshaft support member in combination with a drive including a worm gear and a servomotor located on an engine block. The camshafts are driven by the crankshaft coupled with an idler gear. The idler gear is coupled with the camshaft gears through reduction gears, reducing the overall size of the drive and allowing flexibility as to valve timing.

Abstract: The present invention provides methods to take advantage of the exhaust gas pulses in an exhaust system of a multi-cylinder internal combustion engine to increase the volumetric efficiency over the complete operating range of the engine. It solves the problems of other systems which are only able to gain a beneficial effect from the exhaust gas pulses over a limited range of the engine operating speeds, by providing a means of varying the exhaust pipe lengths, combinations, and cross-sectional area of the exhaust passages of the multi-cylinder internal combustion engine. By this means it provides an exhaust system in which the exhaust gas pulse frequencies can be varied over the entire operating range of the engine to obtain desirable pulse frequencies matching the cylinder exhaust timing for efficient extraction of the exhaust gases, improvement in volumetric efficiency and a higher maximum engine speed.