Abstract: In a water-absorbent resin production apparatus for producing a water-absorbent resin by polymerizing a water-soluble ethylenically unsaturated monomer, a water-absorbent resin powder obtained by drying a water-absorbent resin composition with a dryer passes through a first powder flow path pipe, is discharged therefrom toward a classifier while a flow rate is regulated so as to a predetermined value by a powder flow rate regulating discharge member composed of a hopper and a rotary valve, and is classified by the classifier. In the water-absorbent resin production apparatus, a collector for collecting a powder aggregate composed of aggregated particles of the water-absorbent resin powder is disposed in the first powder flow path pipe. Accordingly, a water-absorbent resin in the form of a particulate powder from which the powder aggregate is removed can be produced at a high production efficiency.

Abstract: In a water-absorbent resin production apparatus for producing a water-absorbent resin by polymerizing a water-soluble ethlenically unsaturated monomer, a water-absorbent resin powder obtained by drying a water-absorbent resin composition with a dryer passes through a first powder flow path pipe, is discharged therefrom toward a classifier while a flow rate is regulated so as to a predetermined value by a powder flow rate regulating discharge member composed of a hopper and a rotary valve, and is classified by the classifier. In the water-absorbent resin production apparatus, a collector for collecting a powder aggregate composed of aggregated particles of the water-absorbent resin powder is disposed in the first powder flow path pipe. Accordingly, a water-absorbent resin in the form of a particulate powder from which the powder aggregate is removed can be produced at a high production efficiency.

Abstract: The present invention provides a process for producing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine represented by Formula (1); wherein R is a C1-4 alkyl, the method comprising the steps of: maintaining a solution containing (Z)—N-monoalkyl-3-oxo-3-(2-thienyl)propenamine dissolved therein at 25° C. or below to deposit crystals and separating crystals having a particle diameter of 100 ?m or less from the deposited crystals; and a process for producing (E,Z)—N-monoalkyl-3-oxo-3-(2-thienyl)propenamine comprising the steps of: reacting an alkali metal salt of ?-oxo-?-(2-thienyl)propanal with a monoalkylamine compound; adding a water-insoluble organic solvent to the resulting reaction mixture; adding seed crystals containing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine to an organic layer obtained by conducting separation; and keeping the resulting mixture at 25° C. or below.

Abstract: The present invention provides a process for producing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine represented by Formula (1); wherein R is a C1-4 alkyl, the method comprising the steps of: maintaining a solution containing (Z)—N-monoalkyl-3-oxo-3-(2-thienyl)propenamine dissolved therein at 25° C. or below to deposit crystals and separating crystals having a particle diameter of 100 ?m or less from the deposited crystals; and a process for producing (E,Z)—N-monoalkyl-3-oxo-3-(2-thienyl)propenamine comprising the steps of: reacting an alkali metal salt of ?-oxo-?-(2-thienyl)propanal with a monoalkylamine compound; adding a water-insoluble organic solvent to the resulting reaction mixture; adding seed crystals containing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine to an organic layer obtained by conducting separation; and keeping the resulting mixture at 25° C. or below.

Abstract: The present invention provides a process for producing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine represented by Formula (1); wherein R is a C1-4 alkyl, the method comprising the steps of: maintaining a solution containing (Z)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine dissolved therein at 25° C. or below to deposit crystals and separating crystals having a particle diameter of 100 ?m or less from the deposited crystals; and a process for producing (E,Z)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine comprising the steps of: reacting an alkali metal salt of ?-oxo-?-(2-thienyl)propanal with a monoalkylamine compound; adding a water-insoluble organic solvent to the resulting reaction mixture; adding seed crystals containing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine to an organic layer obtained by conducting separation; and keeping the resulting mixture at 25° C. or below.

Abstract: The present invention provides a process for producing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine represented by Formula (1); wherein R is a C1-4 alkyl, the method comprising the steps of: maintaining a solution containing (Z)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine dissolved therein at 25° C. or below to deposit crystals and separating crystals having a particle diameter of 100 ?m or less from the deposited crystals; and a process for producing (E,Z)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine comprising the steps of: reacting an alkali metal salt of ?-oxo-?-(2-thienyl)propanal with a monoalkylamine compound; adding a water-insoluble organic solvent to the resulting reaction mixture; adding seed crystals containing (E)-N-monoalkyl-3-oxo-3-(2-thienyl)propenamine to an organic layer obtained by conducting separation; and keeping the resulting mixture at 25° C. or below.