An absorbent core including one or more nonwoven webs with superabsorbent fibers. The superabsorbent fibers may include one or more surfactants. The one or more nonwoven webs have an amount of extractables of less than 20 weight-%, and/or an amount of titratable soluble of less than 20%. The nonwoven webs have a capacity of at least 7 g/g. The absorbent core may be used in an absorbent article.

Provided is a water-absorbing agent that causes no or little fluctuation of feed rate when fed with use of a feeder. A water-absorbing agent containing a water-absorbing resin as a main component, the water-absorbing agent satisfying the following (a) and (b): (a) K-index is 70 or more; and (b) Moisture absorption blocking ratio, after 30 minutes of standing at a temperature of 25° C. and a relative humidity of 80% RH, is 70 weight % or less, the K-index being defined by the following equation: K-index=100−(−438+3.6×angle of repose+3.5×angle of difference+7.9×compressibility rate+290×bulk density (EDANA method)).

An absorbent core and an absorbent article respectively with improved properties, especially rewet performance, are disclosed. The absorbent core has at least two layers, wherein each layer comprising from 0 to 10% by weight fibrous material and from 90 to 100% by weight water-absorbent polymer particles, based on the sum of water-absorbent polymer particles and fibrous material. The surface-postcrosslinked water absorbent polymer particles within the upper layer have a sphericity of at least 0.89 and a CRC of at least 34 g/g. Preferably the water-absorbent polymer particles have a sphericity of at least 0.89 and the sum of the CRC and AUL (0.3 psi, 21 g cm.sup.−2) (EDANA 442.2-02) of the water absorbent polymer particles is at least 65 g/g.

It is an object of the present invention to provide a novel water-absorbing sheet that can meaningfully reduce the return amount even when introduction of a liquid occurs intermittently for several times (particularly, three or more times) under a situation with no load, and the amount of introduction of the liquid becomes large.

Disclosed is a water-absorbing sheet having a first base material, a second base material, and a water-absorbing layer positioned between the first base material and the second base material, wherein the first base material is a water-permeable sheet positioned on a side where a liquid to be absorbed is introduced, the water-absorbing layer has a first particulate water absorbent localized on a side of a surf ace of the first base material, the surface being arranged to face the second base material; and a second particulate water absorbent localized on a side of a surface of the second base material, the surface being arranged to face the first base material, an overall absorption amount of the second particulate water absorbent as represented by the following formula:

CRC g/g+0.44×AAP2.1 kPa g/g

is 48 g/g or more, and a water absorption time determined according to a vortex method is 35 seconds or more.

Disclosed is an absorbent article with biocompostable properties, such as a baby diaper, adult incontinence product, or a feminine hygiene pad. Particularly, the present invention is directed to a biocompostable absorbent sanitary article with a high degree of biocompostability. The sanitary article comprises, in one embodiment, at least a top layer, a back layer, and absorbent core, wherein the absorbent core includes a superabsorbent polymer, and wherein at least the superabsorbent polymer is biocompostable.

Disclosed is an absorbent article with biocompostable properties, such as a baby diaper, adult incontinence product, or a feminine hygiene pad. Particularly, the present invention is directed to a biocompostable absorbent sanitary article with a high degree of biocompostability. The sanitary article comprises, in one embodiment, at least a top layer, a back layer, and absorbent core, wherein the absorbent core includes a superabsorbent polymer, and wherein at least the superabsorbent polymer is biocompostable.

Provided is a water-absorbing agent that causes no or little fluctuation of feed rate when fed with use of a feeder. A water-absorbing agent containing a water-absorbing resin as a main component, the water-absorbing agent satisfying the following (a) and (b): (a) K-index is 70 or more; and (b) Moisture absorption blocking ratio, after 30 minutes of standing at a temperature of 25 C. and a relative humidity of 80% RH, is 70 weight % or less, the K-index being defined by the following equation: K-index=100(438+3.6angle of repose+3.5angle of difference+7.9compressibility rate+290bulk density (EDANA method)).

An absorbent core and an absorbent article respectively with improved properties, especially rewet performance, are disclosed. The absorbent core has at least two layers, wherein each layer comprising from 0 to 10% by weight fibrous material and from 90 to 100% by weight water-absorbent polymer particles, based on the sum of water-absorbent polymer particles and fibrous material. The surface-postcrosslinked water absorbent polymer particles within the upper layer have a sphericity of at least 0.89 and a CRC of at least 34 g/g. Preferably the water-absorbent polymer particles have a sphericity of at least 0.89 and the sum of the CRC and AUL (0.3 psi, 21 g cm.sup.2) (EDANA 442.2-02) of the water absorbent polymer particles is at least 65 g/g.

Disclosed is an absorbent article with biocompostable properties, such as a baby diaper, adult incontinence product, or a feminine hygiene pad. Particularly, the present invention is directed to a biocompostable absorbent sanitary article with a high degree of biocompostability. The sanitary article comprises, in one embodiment, at least a top layer, a back layer, and absorbent core, wherein the absorbent core includes a superabsorbent polymer, and wherein at least the superabsorbent polymer is biocompostable.

An absorbent core including one or more nonwoven webs with superabsorbent fibers. The superabsorbent fibers may include one or more surfactants. The one or more nonwoven webs have an amount of extractables of less than 20 weight-%, and/or an amount of titratable soluble of less than 20%. The nonwoven webs have a capacity of at least 7 g/g. The absorbent core may be used in an absorbent article.