摘要:
[PROBLEM]It is an object of the present invention to efficiently obtain efficiently a water-absorbent resin having excellent property.[SOLUTION]A production method for a water-absorbent resin, comprising: a polymerization step for obtaining hydrogel by subjecting a monomer aqueous solution to a polymerization reaction; and a drying step for drying the hydrogel; wherein drying in the drying step is performed using a continuous through-flow belt-type drying machine; solid content of the hydrogel supplied to the drying step is 35% by weight or more, and thickness variation rate (1) represented by the following EXPRESSION 1 of the hydrogel loaded onto through-flow belt in the continuous through-flow belt, is 1.05 to 5: [MATH. 1] Thickness variation rate (1)=(Maximum thickness of hydrogel in a width direction of the through-flow belt)/(Average thickness of hydrogel in a width direction of the through-flow belt). [EXPRESSION 1]
摘要:
A production method for a water-absorbent resin, comprising a polymerization step for obtaining hydrogel by subjecting a monomer aqueous solution to a polymerization reaction, and a drying step for drying the hydrogel, wherein drying in the drying step is performed using a continuous through-flow belt-type drying machine, the solid content of the hydrogel supplied to the drying step is 35% by weight or more, and thickness variation rate (1) represented by the following EXPRESSION 1 of the hydrogel loaded onto through-flow belt in the continuous through-flow belt, is 1.05 to 5: [MATH. 1] Thickness variation rate (1)=(Maximum thickness of hydrogel in a width direction of the through-flow belt)/(Average thickness of hydrogel in a width direction of the through-flow belt). [EXPRESSION 1]
摘要:
The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.
摘要:
The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.
摘要:
The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.
摘要:
The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.
摘要:
The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.
摘要:
The present invention provides a production process by which a water-absorbent resin of excellent quality can be obtained at a low cost by reasonable steps in aqueous solution polymerization. The process for producing a water-absorbent resin comprises the step of polymerizing an aqueous solution of water-absorbent resin-forming monomers including acrylic acid and/or its sodium salt as major components, wherein: (1) the aqueous solution has a monomer component concentration of not less than 45 weight %; (2) the polymerization is carried out while water is evaporated so that the ratio (concentration ratio) between a solid component concentration in a hydropolymer as formed by the polymerization and a solid component concentration in the aqueous monomer solution will not be less than 1.10; and (3) the solid component concentration in the hydropolymer as formed by the polymerization is not more than 80 weight %.
摘要:
A production method for a water-absorbent resin, comprising a polymerization step for obtaining hydrogel by subjecting a monomer aqueous solution to a polymerization reaction, and a drying step for drying the hydrogel, wherein drying in the drying step is performed using a continuous through-flow belt-type drying machine, the pore opening rate of the through-flow belt in the continuous through-flow belt-type drying machine is 20 to 50%, the solid content of the hydrogel supplied to the drying step is 35% by weight or more, and the area occupancy rate of the hydrogel is 85 to 100% relative to the through-flow belt.
摘要:
Provided is a method which does not require alteration of the raw materials or high capital investment, and improves and stabilizes the physical property (for example, liquid permeability) of a water absorbent resin by means of a simple technique. A method for producing a water absorbent resin is disclosed, which method includes a polymerization step of polymerizing an aqueous solution of acrylic acid (salt) to obtain a water-containing gel-like crosslinked polymer; a drying step of drying the water-containing gel-like crosslinked polymer to obtain a water absorbent resin powder; a classification step of classifying the water absorbent resin powder; and a surface crosslinking step of surface crosslinking the water absorbent resin powder, wherein in the classification steps that are carried before the surface crosslinking step and/or after the surface crosslinking step, the stretch tension (tension) of the metal sieve mesh used in the classification step is from 35 [N/cm] to 100 [N/cm].