Abstract: It is an object of the present invention to provide a method for producing ultrafine fibrous cellulose, which is capable of efficiently obtaining ultrafine fibrous cellulose having phosphoric acid groups with a high yield. The present invention relates to a method for producing fibrous cellulose having a fiber width of 1000 nm or less, comprising: a (A) of introducing phosphoric acid groups into cellulose fibers to form crosslinked structures via the phosphoric acid groups, thereby obtaining crosslinked phosphorylated cellulose fibers, a (B) of breaking some or all of the crosslinked structures to obtain crosslink-broken phosphorylated cellulose fibers, and a (C) of performing a mechanical treatment on the crosslink-broken phosphorylated cellulose fibers to obtain fibrous cellulose having a fiber width of 1000 nm or less, wherein, in the (A), crosslinked structures in an amount of 0.05 mmol/g or more and 2.

Abstract: It is an object of the present invention to provide a method for producing ultrafine fibrous cellulose, which is capable of efficiently obtaining ultrafine fibrous cellulose having phosphoric acid groups with a high yield. The present invention relates to a method for producing fibrous cellulose having a fiber width of 1000 nm or less, comprising: a (A) of introducing phosphoric acid groups into cellulose fibers to form crosslinked structures via the phosphoric acid groups, thereby obtaining crosslinked phosphorylated cellulose fibers, a (B) of breaking some or all of the crosslinked structures to obtain crosslink-broken phosphorylated cellulose fibers, and a (C) of performing a mechanical treatment on the crosslink-broken phosphorylated cellulose fibers to obtain fibrous cellulose having a fiber width of 1000 nm or less, wherein, in the (A), crosslinked structures in an amount of 0.05 mmol/g or more and 2.

Abstract: Provided is an absorbent resin composition which has both improved absorbency under load and improved liquid permeability between swollen gels, which is free from blocking or discoloration during storage, and which does not generate any odors. The present invention is an absorbent resin composition containing: a crosslinked polymer (A) including, as an essential structural units, a crosslinking agent (b) and a water-soluble vinyl monomer (a1) and/or a vinyl monomer (a2) which produces the water-soluble vinyl monomer (a1) through hydrolysis; and a cationic organic polymer (c) having a number average molecular weight of 1,000,000 or higher, or a cationic organic polymer (B) that has a cationic group and that is obtained through polymerization of a monomer composition including, as essential components, a cationic monomer having an amino group (am) and/or a cationic monomer having a salt of an amino group (am).

Abstract: Provided is a method for producing water-absorbent resin particles, which is capable of improving the gel strength for the purpose of achieving a good balance between the absorption under load and the rate of liquid permeation through gel. The present invention is a method for producing water-absorbent resin particles, which is characterized by comprising a step wherein a monomer composition containing a water-soluble vinyl monomer (a1) and/or a vinyl monomer (a2) that turns into a water-soluble vinyl monomer (a1) by means of hydrolysis and a crosslinking agent (b) is polymerized in the presence of at least one organic main group element compound selected from the group consisting of organic iodine compounds, organic tellurium compounds, organic antimony compounds, and organic bismuth compounds.

Abstract: Provided is a process for producing aqueous-liquid absorbing resin particles which, even after transportation or a diaper production step, are capable of combining the property of enabling liquid passing through interstices among the swollen gel particles with absorption performance under load. The present invention is: a process for producing aqueous-liquid absorbing resin articles (P), characterized by subjecting resin particles (B) that comprise a crosslinked polymer (A) comprising essential constituent units derived from a water-soluble vinyl monomer (a1) and/or a vinyl monomer (a2) which become a water-soluble vinyl monomer (al) upon hydrolysis and from a crosslinking agent (b), to surface treatment by a specific method using a C4 or lower polyhydric alcohol (c), a polyvalent metal salt (d), and a polyglycidyl compound (e); and the aqueous-liquid absorbing resin articles (P).

Abstract: Provided are aqueous-liquid absorbent resin particles in which the aqueous-liquid absorbent resin is not blocked regardless of working environment or weather condition, and that have excellent powder feedability and absorption performance under a load. The present invention pertains to aqueous-liquid absorbent resin articles (P) obtained by a production method comprising at least two steps of surface crosslinking step for crosslinking, by using a surface crosslinking agent (c), the surfaces of resin particles (B) containing a crosslinked polymer (A) of which the essential constitutional unit is formed of a water-soluble vinyl monomer (a1), and/or a vinyl monomer (a2) that becomes a water-soluble vinyl monomer (a1) through hydrolysis, and a crosslinking agent (b). The surface crosslinking agent (c) used is different between the first surface crosslinking step and the second crosslinking step.