Abstract: To provide a water absorbing agent which is excellent in balance between absorbency and liquid permeability against pressure and is excellent in flowability at the time of moisture absorption. The water absorbing agent comprises water absorbent resin particles and an organic surface additive, wherein: the organic surface additive having (i) a reactive group for a functional group of a surface of each water absorbent resin particle and (ii) a hydrophobic group exists on the surface of the water absorbent resin particle, and the hydrophobic group has a hydrocarbon group whose carbon number is 8 or more, and a ratio of an oxyalkylene group in a molecular mass of the organic surface additive is 0 or more and 25 mass % or less.

Abstract: The present invention provides a water absorbing agent, including: water absorbent resin particles; and a modified cationic polymer compound containing a primary amino group and/or a secondary amino group, the modified cationic polymer compound being obtained by reacting, with a modifying agent, a cationic polymer compound containing the primary amino group and/or the secondary amino group, and the modifying agent containing two or more carbon atoms continuously linked, and one reactive group which reacts with the primary amino group and/or the secondary amino group. The present invention further provides a method for producing a water absorbing agent including water absorbent resin particles, the method including the step (i) of mixing the water absorbent resin particles with a modified cationic polymer compound.

Abstract: The production method of a water absorbent resin composition including a particulate water absorbent resin, wherein: 95 wt % or more of particles whose particle diameter is less than 850 ?m and not less, than 106 ?m are contained, and a weight average particle diameter of the particles is less than 500 ?m and not less than 300 ?m and a logarithmic standard deviation (??) of a particle size distribution is 0.45 or less, and a water-soluble component of the water absorbent composition is 35 wt % or less, and a multivalent metal component is contained, and an extraction rate of the multivalent metal component is 5.0 wt % or more and less than 100 wt %, thereby providing the water absorbent resin composition, free from any coagulation of particles in high humidity, which has superior absorbent property in terms of an absorbency and a diffusing absorbency under pressure.

Abstract: The present invention provides a water absorbing agent, and a method for producing the water absorbing agent. The water absorbing agent includes water absorbent resin particles, an organic acid and/or salt thereof having carbon number of 10 or more and not more than 30 in its molecule, and a water-soluble polyvalent cation. The method includes the step (i) of mixing the water absorbent resin particles, the organic acid and/or salt thereof having carbon number of 10 or more and not more than 30 in its molecule, and the water-soluble polyvalent cation with one another.

Abstract: The present invention is to provide a super-absorbent resin which can be used to design an absorbing core or absorbing goods capable of being flown into a flushing toilet. The present invention relates to a super-absorbent resin having as a main component thereof a repeating unit having an ionic dissociation group in its main or side chain, wherein said resin has absorption capacity without load to saline solution (CRCs) for 4 hours of not smaller than 10 g/g, and solubility in ion-exchanged water of not lower than 50% by weight.

Abstract: The present invention provides a water absorbing agent that is excellent in a balance between a centrifugal retention capacity (CRC) and a saline flow conductivity (SFC), and a method for producing the water absorbing agent. The method for producing the water absorbing agent, the method comprising mixing (i) a water absorbing resin (A) and (ii) a polymer (B) being a polyamine polymer having a hydroxyl group on a main chain provides a water absorbing agent containing (i) the water absorbing resin (A) and (ii) the polymer (B) being a polyamine polymer having a hydroxyl group on a main chain.

Abstract: A water-absorbing goods having excellent absorption performance in practical use is to be provided at low price. A particulate water-absorbing agent provided by one aspect of the present invention is a particulate water-absorbing agent comprising a polyacrylate salt-type water-absorbing resin as a main component, and satisfying the following (a) and (b): (a) absorption capacity without load in artificial urine (A) is equal to or higher than 60 g/g; and (b) an increase rate of absorption capacity without load in artificial urine (B) relative to artificial urine (A) is equal to or larger than 20%.

Abstract: A particulate water absorbing agent of the present invention includes a water absorbent resin, having a cross-linking structure, whose surface has been cross-linked by adding a surface treatment agent, wherein: (i) a mass average particle diameter (D50) ranges from 200 to 600 ?m and 95 to 100 wt % of a particulate water absorbing agent whose particle diameter ranges from less than 850 ?m to not less than 150 ?m is contained with respect to 100 wt % of whole the particulate water absorbing agent, and (ii) a logarithmic standard deviation (??) of particle size distribution ranges from 0.25 to 0.45, and (iii) a compressibility rate defined by a following equation ranges from 0 to 18%, and (iv) a surface tension of a supernatant liquid obtained in 4 minutes after dispersing 0.5 g of the particulate water absorbing agent in 50 ml of physiological saline whose temperature is 20° C.

Abstract: The present invention provides a particulate water absorbing agent for a thin type absorbing substrate suitable for actual use. A particulate water absorbing agent having irregularly pulverized shape, characterized by comprising, a surface crosslinked water-absorbing resin obtained by crosslinking polymerization of an unsaturated monomer with an acid group and/or salts thereof, which absorbing agent contains agglomerated particles therein and further satisfies (i) centrifuge retention capacity (CRC) in a physiological saline solution of not lower than 32 g/g, (ii) mass median particle size (D50) of 200 to 400 ?m, and (iii) particles smaller than 600 ?m and not smaller than 150 ?m of 95 to 100% by weight. By using the particulate water absorbing agent, such absorbing articles can be obtained as have few rugged surface after water absorption, excellent liquid permeation property.

Abstract: A particulate water absorbing agent of the present invention includes a water absorbent resin, having a cross-linking structure, whose surface has been cross-linked by adding a surface treatment agent, wherein: (i) a mass average particle diameter (D50) ranges from 200 to 600 ?m and 95 to 100 wt % of a particulate water absorbing agent whose particle diameter ranges from less than 850 ?m to not less than 150 ?m is contained with respect to 100 wt % of whole the particulate water absorbing agent, and (ii) a logarithmic standard deviation (??) of particle size distribution ranges from 0.25 to 0.45, and (iii) a compressibility rate defined by a following equation ranges from 0 to 18%, and (iv) a surface tension of a supernatant liquid obtained in 4 minutes after dispersing 0.5 g of the particulate water absorbing agent in 50 ml of physiological saline whose temperature is 20° C.

Abstract: A particulate water absorbing agent of the present invention includes a water absorbent resin, having a cross-linking structure, whose surface has been cross-linked by adding a surface treatment agent, wherein: (i) a mass average particle diameter (D50) ranges from 200 to 600 ?m and 95 to 100 wt % of a particulate water absorbing agent whose particle diameter ranges from less than 850 ?m to not less than 150 ?m is contained with respect to 100 wt % of whole the particulate water absorbing agent, and (ii) a logarithmic standard deviation (??) of particle size distribution ranges from 0.25 to 0.45, and (iii) a compressibility rate defined by a following equation ranges from 0 to 18%, and (iv) a surface tension of a supernatant liquid obtained in 4 minutes after dispersing 0.5 g of the particulate water absorbing agent in 50 ml of physiological saline whose temperature is 20° C.

Abstract: A particulate water absorbent contains a water absorbent resin as a main component, the water absorbent resin being a crosslinked polymer of a water-soluble unsaturated monomer. The water absorbent resin is particular in shape and contains particles of a particle size in a range of not less than 106 ?m and less than 850 ?m in an amount of not less than 90 mass percent with respect to the total mass of the water absorbent resin contained in the particulate water absorbent. The particulate water absorbent has a first salt concentration absorption index of not less than 0.60 as measured by a formula below when ion exchange water is used as an aqueous solution of a constant salt concentration: (salt concentration absorption index)=(absorbency against a pressure of 4.83 kPa with respect to the aqueous solution of a constant salt concentration)/(absorbency against no pressure with respect to the aqueous solution of a constant salt concentration).

Abstract: To provide a water absorbing agent which is excellent in balance between absorbency and liquid permeability against pressure and is excellent in flowability at the time of moisture absorption. The water absorbing agent comprises water absorbent resin particles and an organic surface additive, wherein: the organic surface additive having (i) a reactive group for a functional group of a surface of each water absorbent resin particle and (ii) a hydrophobic group exists on the surface of the water absorbent resin particle, and the hydrophobic group has a hydrocarbon group whose carbon number is 8 or more, and a ratio of an oxyalkylene group in a molecular mass of the organic surface additive is 0 or more and 25 mass % or less.

Abstract: A homogeneously surface cross-linked water absorbent resin and a method for the production thereof are provided. The water absorbent material is formed of a surface cross-linked water absorbent resin resulting from granular irregularly pulverized shaped surface cross-linking the product of partial neutralization or whole neutralization of a water absorbent resin having acrylic acid or a metal salt thereof as a main component, which water absorbent material shows a metal atom concentration on the surface of the water absorbent material in the range of 0-10% within 0 second of polishing and 2-35% at 10 seconds value of polishing as determined by subjecting the water absorbent material to Ar ion discharge polishing under a voltage of 500 ?. The surface cross-linked water absorbent resin to be used herein can be produced by surface cross-linking a water absorbent resin having a specific particle diameter with a surface cross-linking agent having a water concentration in a specific range.

Abstract: An object of the present invention is to provide a particulate water-absorbent resin composition which is so excellent that: the absorption ability in an initial short time is secured in some degree, and further, the absorption capacity lastingly increases over a long period, and also the liquid permeability and the liquid diffusibility can be secured. As a means of achieving this object, a particulate water-absorbent resin composition according to the present invention is a particulate water-absorbent resin composition comprising a carboxyl-group-containing water-absorbent resin in an amount of not smaller than 80 mass %, with the composition being characterized by being: not less than 20 g/g in specific-particle-diameter absorption capacity under load (0.29 psi (2.00 kPa), 1 hour); and not less than 3 g/g in specific-particle-diameter absorption index increment in 20 hours.

Abstract: The particulate water absorbent has a cross-linking structure therein, and contains (i) a particulate water absorbent resin having a cross-linking structure on a surface therof and (ii) not less than 0.001 mass % and less than 10 mass % of anorganic acid multivalent metal salt whose molecule contains not less than seven carbon atoms. Futher, the particulate water absorbent contains 90 mass % of particles, whose particle diameter is not less than 106 ?m and 850 ?m, with respect to the particulate water absorbent.

Abstract: The present invention provides a particulate water absorbing agent for a thin type absorbing substrate suitable for actual use. A particulate water absorbing agent having irregularly pulverized shape, characterized by comprising, a surface crosslinked water-absorbing resin obtained by crosslinking polymerization of an unsaturated monomer with an acid group and/or salts thereof, which absorbing agent contains agglomerated particles therein and further satisfies (i) centrifuge retention capacity (CRC) in a physiological saline solution of not lower than 32 g/g, (ii) mass median particle size (D50) of 200 to 400 ?m, and (iii) particles smaller than 600 ?m and not smaller than 150 ?m of 95 to 100% by weight. By using the particulate water absorbing agent, such absorbing articles can be obtained as have few rugged surface after water absorption, excellent liquid permeation property.

Abstract: The production method of a water absorbent resin composition including a particulate water absorbent resin, wherein: 95 wt % or more of particles whose particle diameter is less than 850 ?m and not less, than 106 ?m are contained, and a weight average particle diameter of the particles is less than 500 ?m and not less than 300 ?m and a logarithmic standard deviation (??) of a particle size distribution is 0.45 or less, and a water-soluble component of the water absorbent composition is 35 wt % or less, and a multivalent metal component is contained, and an extraction rate of the multivalent metal component is 5.0 wt % or more and less than 100 wt %, thereby providing the water absorbent resin composition, free from any coagulation of particles in high humidity, which has superior absorbent property in terms of an absorbency and a diffusing absorbency under pressure.

Abstract: A particulate water retaining material for cultivating plant comprising (A) a carboxyl group-containing water-insoluble water absorbent resin and (B) a polyvalent metal compound, by having the compound (B) deposited on the the rerin (A), it is made possible to possess an outstanding water absorbing property without impairing the growth of a plant.

Abstract: The present invention is to provide a super-absorbent resin which can be used to design an absorbing core or absorbing goods capable of being flown into a flushing toilet. The present invention relates to a super-absorbent resin having as a main component thereof a repeating unit having an ionic dissociation group in its main or side chain, wherein said resin has absorption capacity without load to saline solution (CRCs) for 4 hours of not smaller than 10 g/g, and solubility in ion-exchanged water of not lower than 50% by weight.