Abstract: The invention relates to a process for producing superabsorbent polymer particles, comprising polymerization of a monomer solution, drying the formed polymer gel, grinding the dried polymer gel, classifying and thermally surface post-crosslinking the polymer particles, wherein the monomer solution comprises a chelating agent and an aluminum salt.

Abstract: In an improved superabsorbent complexed with aluminum ions, the aluminum ions are applied in the form of an aqueous solution comprising aluminum ions, which has the feature that it comprises aluminum ions in a proportion within the range of 0.5%-15% by weight (converted if appropriate to Al3+), based on the total mass of the solution, and further comprises anions of lactic acid (lactate ions) and phosphoric acid (phosphate ions), where the molar proportion of the lactate ions is within the range of 0.01-2.99 times the molar amount of Al3+ and the molar proportion of the phosphate ions is within the range of 0.01-2.99 times the molar amount of Al3+.

Abstract: The present disclosure relates to fluid absorbent cores including at least one absorption layer, the layer including at least 80% by weight of water-absorbent polymer particles, 0 to 10% by weight of an adhesive and from 0 to 10% by weight of fibrous material, wherein the water-absorbent polymer particles within the absorption layer are water-absorbent polymer particles having a vortex of 40 s or less and having a roundness of 0.79 to 0.85 and/or a CRC of 38 g/g to 85 g/g.

Abstract: The invention relates to a process for producing long-term color stable superabsorbent polymer particles, comprising polymerization of a monomer solution, drying the resulting polymer gel, optionally grinding and classifying the resulting dried polymer gel and thermally surface post-crosslinking and cooling the resulting polymer particles, wherein a thermal surface post-cross-linker and hydrogen peroxide are added to the polymer particles prior to the thermal surface post-crosslinking.

Abstract: The present invention relates to a process for producing surface-postcrosslinked water-absorbent polymer particles by coating of water-absorbent polymer particles having a content of residual monomers in the range from 0.03 to 15% by weight with at least one surface-postcrosslinker and thermal surface-postcrosslinking at temperatures in the range from 100 to 180° C.

Abstract: Described herein is a feminine hygiene absorbent article, including: (A) an upper liquid-pervious layer, (B) a lower liquid-impervious layer, (C) a fluid-absorbent core between the layer (A) and the layer (B), including 5% to 50% by weight of water-absorbent polymer particles G and not more than 95% by weight of fibrous material, based on the sum of water-absorbent polymer particles G and fibrous material; (D) an optional acquisition-distribution layer between (A) and (C), (E) an optional tissue layer disposed immediately above and/or below (C); and (F) other optional components, where the water-absorbent polymer particles G are obtainable by agglomerating a blend of non-surface post-crosslinked fine water-absorbent polymer particles and surface post-crosslinked fine water-absorbent polymer particles, and drying, grinding, sieving and classifying the agglomerated water-absorbent polymer particles.

Abstract: Described herein is a fluid-absorbent core including at least two layers, an upper layer and a lower layer, each layer including 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, where within the upper layer (91) is a water absorbent mixture including at least 10% by weight of a first type of water-absorbent polymer particles, water-absorbent polymer particles G, with a vortex of less than 30 s and at least 50% by weight of a second type of water-absorbent polymer particles, water-absorbent polymer particles H, with a CRC of at least 25 g/g. Also described herein is a fluid-absorbent article including the fluid-absorbent core.

Abstract: In an improved superabsorbent complexed with aluminum ions, the aluminum ions are applied in the form of an aqueous solution comprising aluminum ions, which has the feature that it comprises aluminum ions in a proportion within the range of 0.5%-15% by weight (converted if appropriate to Al3+), based on the total mass of the solution, and further comprises anions of lactic acid (lactate ions) and phosphoric acid (phosphate ions), where the molar proportion of the lactate ions is within the range of 0.01-2.99 times the molar amount of Al3+ and the molar proportion of the phosphate ions is within the range of 0.01-2.99 times the molar amount of Al3+.

Abstract: The present disclosure relates to fluid absorbent cores including at least one absorption layer, the layer including at least 80% by weight of water-absorbent polymer particles, 0 to 10% by weight of an adhesive and from 0 to 10% by weight of fibrous material, wherein the water-absorbent polymer particles within the absorption layer are water-absorbent polymer particles having a vortex of 40 s or less and having a roundness of 0.79 to 0.85 and/or a CRC of 38 g/g to 85 g/g.

Abstract: The invention relates to a process for producing long-term color stable superabsorbent polymer particles, comprising polymerization of a monomer solution, wherein the monomer solution comprises at least 0.01% by weight of 1-hydroxyethane-1,1-diphosphonic acid or a salt thereof and at least 0.01% by weight of 2-hydroxy-2-sulfonatoacetic acid or a salt thereof.

Abstract: 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?2) (EDANA 442.2-02) of the water absorbent polymer particles is at least 65 g/g.

Abstract: The present invention relates to a process for producing surface-postcrosslinked water-absorbent polymer particles by coating of water-absorbent polymer particles having a content of residual monomers in the range from 0.03 to 15% by weight with at least one surface-postcrosslinker and thermal surface-postcrosslinking at temperatures in the range from 100 to 180° C.

Abstract: The invention relates to a process for producing superabsorbents, comprising the preparation of partly neutralized acrylic acid by the steps (i) preparing an over-neutralized acrylic acid having a degree of neutralization of at least 100.1 mol-% by mixing of an acrylic acid 1 and a base and (ii) preparing a neutralized acrylic acid having a degree of neutralization from 50 to 85 mol-% by mixing of the over-neutralized acrylic acid and an acrylic acid 2, wherein the content of dimeric acrylic acid in the acrylic acid 2 is lower than the content of dimeric acrylic acid in the acrylic acid 1.

Abstract: The present invention relates to a process for producing surface-postcrosslinked water-absorbent polymer particles by coating of water-absorbent polymer particles having a content of residual monomers in the range from 0.03 to 15% by weight with at least one surface-postcrosslinker and thermal surface-postcrosslinking at temperatures in the range from 100 to 180° C.

Abstract: The invention relates to a process for producing superabsorbents, comprising the preparation of partly neutralized acrylic acid by the steps (i) preparing an over-neutralized acrylic acid having a degree of neutralization of at least 100.1 mol-% by mixing of an acrylic acid 1 and a base and (ii) preparing a neutralized acrylic acid having a degree of neutralization from 50 to 85 mol-% by mixing of the over-neutralized acrylic acid and an acrylic acid 2, wherein the content of dimeric acrylic acid in the acrylic acid 2 is lower than the content of dimeric acrylic acid in the acrylic acid 1.

Abstract: The present invention relates to a process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution comprising less than 0.3% by weight of persulfate and at least 0.05% by weight of azo initiator and thermal aftertreatment of the formed polymer particles at less than 100° C. in a fluidized bed for 60 to 300 minutes.

Abstract: The present invention relates to a process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution in a surrounding heated gas phase in a reactor comprising a gas distributor (3), a reaction zone (5) and a fluidized bed (27), the gas leaving the reactor is treated in a condenser column (12) with an aqueous solution, the treated gas leaving the condenser column (12) is recycled at least partly to the fluidized bed (27), wherein the gas leaving the condenser column (12) comprises from 0.05 to 0.3 kg steam per kg dry gas and the steam content of the gas entering the gas distributor (3) is less than 80% of the steam content of the gas leaving the condenser column (12).

Abstract: The present invention relates to a process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution comprising less than 0.3% by weight of persulfate and at least 0.05% by weight of azo initiator and thermal aftertreatment of the formed polymer particles at less than 100° C. in a fluidized bed for 60 to 300 minutes.

Abstract: The present invention relates to a fluid-absorbent article, comprising a fluid-absorbent core, comprising from 0 to 90% by weight fibrous material and from 10 to 100% by weight water-absorbent polymer particles having a mean sphericity (SPHT) from 0.8 to 0.95, based on the sum of water-absorbent polymer particles and fibrous material; and an acquisition-distribution layer between having a three dimensional apertured structure having a femal side (5) and a male side (6), wherein the femal side presents a multiplicity of openings extending in the form of through holes in the direction of a lower surface of the same structure being the male side, wherein the quantity of the water absorbent polymer particles within the fluid absorbent core is at least 3 g.

Abstract: The present invention relates to a process for producing water-absorbent polymer particles by polymerizing droplets of a monomer solution comprising less than 0.3% by weight of persulfate and at least 0.05% by weight of azo initiator and thermal aftertreatment of the formed polymer particles at less than 100° C. in a fluidized bed for 60 to 300 minutes.