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)).

Provided is a water-absorbing agent having an excellent ability to absorb and retain liquid and an excellent liquid suction power. The water-absorbing agent contains a polyacrylic acid (salt)-based water-absorbing resin as a main component and satisfies all of the following physical properties (a) to (e): (a) a weight average particle diameter (D50) is 300 μm or more and less than 400 μm; (b) a proportion of particles with a particle diameter of 600 μm or more and less than 850 μm is less than 10 weight %; (c) an average gap radius is 100 μm or more and less than 180 μm; (d) a CRC is 28 g/g or more and less than 34 g/g; and (e) an AAP is 24 g/g or more.

Provided are: a water-absorbing agent achieving, in a balanced manner, both good physical properties and a decrease in speed of coloration with lapse of time even if the water-absorbing agent has a high moisture absorbing speed due to having a large specific surface area; and an absorbent body having a low ratio of pulp and achieving, in a balanced manner, both good physical properties suitable for a thin disposable diaper and a decrease in speed of coloration with lapse of time. The absorbent body contains a hydrophilic base material and a water-absorbing agent which contains: surface-crosslinked water-absorbing resin particles having a non-uniformly pulverized shape; α-hydroxycarboxylic acid (salt); and an aminocarboxylic acid-based chelating agent and/or a phosphorus-based chelating agent, a point plotted along an x-axis that represents an amount (x.sub.1 mol %) of α-hydroxycarboxylic acid (salt) extracted from the water-absorbing agent and along a y-axis that represents an amount (y.sub.1 mmol %) of an aminocarboxylic acid-based chelating agent and/or a phosphorus-based chelating agent extracted from the water-absorbing agent being within a range that satisfies a specific relational formula of x.sub.1 and y.sub.1, the water-absorbing agent having a moisture absorbing speed of 120 mg/g/hr or more at a temperature of 40±1° C. at a relative humidity of 75±1% RH.

The present disclosure relates to a preparation method for a super absorbent polymer film. Specifically, it relates to a preparation method for a new type of super absorbent polymer film, which is thin and exhibits excellent absorption performance. In addition, the super absorbent polymer film of the present disclosure has excellent flexibility and excellent mechanical properties, is free from scattering or leaking, and does not require an auxiliary substance such as pulp, so that products can be made thinner and the manufacturing process and costs may be reduced.

Described herein are superabsorbent polymers that are made of copolymers of multiple charged monomers, where the charged moieties of different charged monomers have different distances from copolymer backbones. The copolymer-based superabsorbent polymers have significantly improved absorbency under load. The compositions and methods described herein are useful in a variety of absorbent products.

The super absorbent polymer comprises: a base polymer powder including a first crosslinked polymer of a water-soluble ethylenically unsaturated monomer having at least partially neutralized acidic groups; and a surface crosslinked layer formed on the base polymer powder and including a second crosslinked polymer in which the first crosslinked polymer is further crosslinked via a surface crosslinking agent, wherein the super absorbent polymer has: a fixed height absorption (FHA) of 22.5 g/g to 29 g/g, a saline flow conductivity (SFC) of 35 (.Math.10.sup.−7 cm.sup.3.Math.s/g) or more, and T-20 of 180 seconds or less.

Provided are a water-absorbing resin having more excellent balance of fluid retention capacity, liquid permeability, and low dustiness and a novel measurement method which enables evaluation of excellent physical properties of the water-absorbing resin. A method for measuring an absorption speed of a particulate water-absorbing agent is a method including the step of applying pressure to a portion of a bottom surface of a measurement container (51) by use of a flat plate (52) in a state in which part or whole of the particulate water-absorbing agent (56) is fixed on the bottom surface of the measurement container (51), the bottom surface being surrounded by a frame, introducing an aqueous solution through a liquid injection inlet (54) with which the flat plate (52) is equipped, and then measuring the amount of time elapsed until an end of absorption of the introduced aqueous solution by the particulate water-absorbing agent (56).

A superabsorbent polymer that may continuously and safely exhibit improved bacterial growth inhibition property and deodorization property, without deterioration of the properties of superabsorbent polymer such as centrifuge retention capacity and absorption under pressure, and the like, and a method for preparing the same are provided.

Described herein are superabsorbent polymers that are made of copolymers of charged monomer and neutral monomers, where the neutral monomers are alkyl or aryl end-capped neutral and hydrophilic monomers that lack free hydroxyl groups and have a water solubility of at least 200 mg/mL. The copolymer-based superabsorbent polymers have significantly improved absorbency under load. The compositions and methods described herein are useful in a variety of absorbent products.

The present disclosure relates to a method for preparing a super absorbent polymer. More specifically, it relates to a method for preparing a super absorbent polymer capable of improving drying efficiency, reducing a generation amount of refines, and simultaneously improving absorption performance, in particular, absorbing under pressure and permeability of the finally prepared super absorbent polymer by controlling granulation strength of the extruded fine reassembly.