Abstract: An object is to provide a water absorbent resin composition containing a water absorbent resin as a main component, with excellent deodorant property and antimicrobial property without impairing appearance and absorption characteristics of the water absorbent resin. The water absorbent resin composition according to the first aspect includes a water absorbent resin containing a polyacrylic acid (salt)-based water absorbent resin as a main component, and an extract of bamboo and an extract of tea. The water absorbent resin composition according to the second aspect includes a water absorbent resin containing a polyacrylic acid (salt)-based water absorbent resin as a main component, and at least two kinds of compounds selected from a group consisting of hexanoic acid (salt), ethyl butyrate, and 3-methyl-2-cyclopenten-1-one.

Abstract: The present invention provides a particulate water absorbing agent for absorbent cores which is excellent in powder conveying property, and achieves sufficient absorption performances for use in absorbent cores in particulate water absorbing agents including a water absorbing resin as a principal component, and which further is suitable for practical applications. In the present invention, characteristics that had not been known conventionally at all, i.e., “permeability potential under pressure (PPUP)” and “frictional charge being a positive charge” of the particulate water absorbing agent are regulated at a time, and furthermore, regulation of the “moisture content of 2 to 10% by weight” is perfected. Also, the particulate water absorbing agent including (A) a water-swelling crosslinked polymer having a constitutional unit derived from an unsaturated monomer containing an acid group and/or a salt thereof; and (B) water fulfills certain requirements.

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-absorbent agent containing a polyacrylate salt-type water-absorbent resin. The agent has an absorption capacity without load of 28 g/g or higher and has a diffusion absorption index of 1.40 to 10.0 g/g min. The amount of water-soluble components in the agent, with stirring, is 15-60% by mass. The difference between this amount and the amount of water-soluble components, without stirring, is 15-50% by mass. Also disclosed is a method of making the above-identified agent.

Abstract: An object of the present invention is to provide a water absorbing agent having a low amount of residual monomer, small variance of the amount of residual monomer among ranges of particle size distribution and favorable absorption properties, and being sanitary; an absorbing article; and a method for the production of a water absorbing agent. The water absorbing agent of the present invention has the amount of residual monomer of not higher than 500 ppm, and a residual monomer index of not greater than 0.30.

Abstract: A water absorbing agent of the present invention has an internal crosslinking structure obtained by polymerization of a water-soluble unsaturated monomer. The agent satisfies conditions (a) to (d): (a) the agent contains water-insoluble inorganic particles at an amount of from 10 ppm to 1,900 ppm inclusive; (b) the agent contains 5 mass % or less particles which have such a size that they can pass through a sieve having a mesh opening size of 150 ?m; (c) the agent has an absorbency against a pressure of 4.83 kPa (AAP) of 18 g/g or more; and (d) the water-insoluble inorganic particles reside on a surface of the water absorbing resin or near the surface.

Abstract: The present invention has an object to provide a particulate water-absorbing composition, a production process therefor, and an absorbent article comprising this particulate water-absorbing composition, wherein the particulate water-absorbing composition causes little coloring of other materials and further is of high safety, and can provide excellent deodorizability and excellent absorption properties to absorbent articles such as diapers in the case where combined into the absorbent articles.

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 water absorbing agent includes water absorbent resin particles which are obtained by polymerizing a water-soluble ethylenic unsaturated monomer and which internally include a cross-linked structure, wherein a pressurized void average radius index is 140 or more. As a result, it is possible to provide a water absorbing agent which essentially includes water absorbent resin particles and is suitable for use in a sanitary material. Specifically, it is possible to improve not only a performance for absorbing and retaining aqueous liquid without pressure or under pressure but also (i) a performance for quickly absorbing aqueous liquid with a great help of a performance of a fibrous material, (ii) a performance for dispersing the aqueous liquid after absorbing the aqueous liquid, and (iii) a performance for retaining the aqueous liquid after absorbing the aqueous liquid.

Abstract: In at least one embodiment, a particulate water-absorbing agent is provided which not only ensures the many conventional physical properties (absorption rate, centrifuge retention capacity, absorbency against pressure, particle size distribution etc.) but also prevents odor which is generated after the resin is swollen by absorption. The water absorbent agent of an embodiment of the present invention therefore does not cause odor in actual use. As a result of intensive study of the foregoing problem, an embodiment of the present invention offers a way of controlling a specific odor component, which is generated from impurities and/or by-product derived from the raw material, after the high temperature process. In this way, an embodiment of the present invention successfully provides a water absorbent agent not causing odor after the resin is swollen by absorption.

Abstract: Reversed phase suspension polymerization is allowed while controlling content of minor components in monomer, particularly controlling a content of acetic acid and propionic acid being not higher than 500 ppm, controlling a content of acrylic acid dimer being not higher than 1000 ppm, in acrylic acid. Cross-linked polymer obtained by the polymerization is subjected to a surface crosslinking treatment without substantially using an organic solvent, and under heating at high temperature (150° C. or higher and 250° C. or lower). Thereafter, agglomeration is carried out without substantially using an organic solvent. Accordingly, a particulate water-absorbing agent including a water-absorbing resin having superior property, and being suited for practical applications at high concentrations in absorbing cores such as a diaper and the like without generation of any odor of the organic solvent can be obtained because no volatile organic compound is included.

Abstract: The present invention provides a particulate water absorbing agent for absorbent cores which is excellent in powder conveying property, and achieves sufficient absorption performances for use in absorbent cores in particulate water absorbing agents including a water absorbing resin as a principal component, and which further is suitable for practical applications. In the present invention, characteristics that had not been known conventionally at all, i.e., “permeability potential under pressure (PPUP)” and “frictional charge being a positive charge” of the particulate water absorbing agent are regulated at a time, and furthermore, regulation of the “moisture content of 2 to 10% by weight” is perfected. Also, the particulate water absorbing agent including (A) a water-swelling crosslinked polymer having a constitutional unit derived from an unsaturated monomer containing an acid group and/or a salt thereof; and (B) water fulfills certain requirements.

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 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: The present invention provides: a water-absorbing agent which has excellent urine resistance; a water-absorbing agent which has not only excellent urine resistance, but also excellent absorption properties that are stable to any composition of urine and show little change with time; and production processes and uses for these water-absorbing agents. The present invention water-absorbing agent exhibits a specific or larger value of absorption capacity under a load in a process in which the absorption capacity under a load is measured in a new manner using a specific liquid to be absorbed, and the present invention provides an absorbent matter and an absorbent article which display a specific or larger value of new absorption index as is, for example, led from the absorption capacity under a load or from the resin concentration using the above water-absorbing agent. The present invention further provides a production process for a water-absorbing agent having the above specific parameter.

Abstract: An embodiment of the present invention allows for production, with a high productivity, of a water-absorbent resin including an improved relationship between absorption capacity and water-soluble polymer which are conflicting properties of the water-absorbent resin, being easily controlled for polymerization reaction, being of no odor, being less colored, and being of high absorption properties. In one embodiment of the present invention, acrylic acid composition is neutralized with a basic composition including an iron content of 0.2 to 5 ppm by weight (relative to a basic compound exclusive of a solvent); and then polymerizing a resultant neutralized product, the acrylic acid composition including: (i) a methoxyphenol content of 10 to 200 ppm by weight relative to the weight of acrylic acid; and (ii) at least one compound content of which is 0 to 10 ppm by weight relative to the weight of acrylic acid, the compound being selected from the group consisting of protoanemonin and furfural.

Abstract: In at least one embodiment, a particulate water-absorbing agent is provided which not only ensures the many conventional physical properties (absorption rate, centrifuge retention capacity, absorbency against pressure, particle size distribution etc.) but also prevents odor which is generated after the resin is swollen by absorption. The water absorbent agent of an embodiment of the present invention therefore does not cause odor in actual use. As a result of intensive study of the foregoing problem, an embodiment of the present invention offers a way of controlling a specific odor component, which is generated from impurities and/or by-product derived from the raw material, after the high temperature process. In this way, an embodiment of the present invention successfully provides a water absorbent agent not causing odor after the resin is swollen by absorption.

Abstract: There is provided: a production process for a water-absorbing agent having stable properties in a short time; and a water-absorbing agent. The production process comprises the step of blending an acid-group-containing water-absorbent resin powder with a noncrosslinkable water-soluble inorganic base and/or an irreducible alkaline-metal-salt pH buffer and further with a dehydratable crosslinking agent reactable with the acid group, thereby subjecting the resin powder to crosslinking treatment, or comprises the step of blending an acid-group-containing water-absorbent resin powder with the above base and/or pH buffer and further with a crosslinking agent reactable with the acid group, thereby subjecting the resin powder to crosslinking treatment, wherein the resin powder has a weight-average particle diameter of 300 to 600 ?m wherein the ratio of fine powders having particle diameters of not larger than 150 ?m in the resin powder is not more than 10 weight %.