The present disclosure relates to lignocellulosic materials comprising phosphorylated lignocellulosic fibers having an ionic charge in water of about 4000 to about 7000 mmoles/kg, and processes for the preparation thereof. The process comprises reacting lignocellulosic fibers of a lignocellulosic material with a phosphate ester in the presence of urea. The present disclosure further relates to compositions comprising a phosphate ester and at least one of a defoamer and a viscosity reducer or at least one of a C1-C12 alcohol and an ester of a carboxylic acid.

It is an object of the present invention to provide a cellulose-containing composition having excellent coating suitability, a production method thereof, and a film. According to the present invention, provided is a cellulose-containing composition comprising cellulose fibers having a fiber width of 1000 nm or less and protein, wherein the protein includes an enzyme, the content of the protein is 1×10.sup.−3 parts by mass or less with respect to 1 part by mass of the cellulose fibers, and when the cellulose-containing composition having a solid concentration of 0.4% by mass is obtained, the viscosity of the cellulose-containing composition measured under conditions of 25° C. and a rotation number of 3 rpm is 10 mPa.Math.s or more and 11000 mPa.Math.s or less.

A method is for manufacturing cellulose microfibers in which a problem of yellowing of cellulose microfibers to be obtained was solved, and cellulose microfibers. As to a method for manufacturing cellulose microfibers, cellulose fibers are added with an additive (A) consisting of at least one of a phosphorous acid and a metal phosphite and an additive (B) consisting of at least one of urea and a urea derivative, heated and washed, then fibrillated. Also, as to cellulose microfibers, the fiber width is 1 to 1000 nm, and a part of hydroxy groups of cellulose fibers is substituted with a functional group represented by a predetermined structural formula to introduce an ester of phosphorous acid.

An object of the present invention is to improve the strength of a sheet containing substituent-introduced ultrafine fiber under high-humidity conditions while maintaining its high transparency. The sheet of the present invention comprises ultrafine fiber having an ionic substituent, and a divalent or higher metal, and has a haze of 10.0% or less.

An object of the present invention is to improve the strength of a sheet containing substituent-introduced ultrafine fiber under high-humidity conditions while maintaining its high transparency. The sheet of the present invention comprises ultrafine fiber having an ionic substituent, and a divalent or higher metal, and has a haze of 10.0% or less.

A method is provided for preparing a fibrous material (preferably a mat or filaments) of crosslinked microfibrillated cellulose. Phosphorylated microfibrillated cellulose is spun into a fibrous material; and then said fibrous material is post-treated (e.g. by heat-treatment) to provide crosslinking between the phosphorylated microfibrillated cellulose. Fibrous materials such as filaments or mats, and hygiene products comprising such materials are also described.

A method is provided for preparing a fibrous material (preferably a mat or filaments) of crosslinked microfibrillated cellulose. Phosphorylated microfibrillated cellulose is spun into a fibrous material; and then said fibrous material is post-treated (e.g. by heat-treatment) to provide crosslinking between the phosphorylated microfibrillated cellulose. Fibrous materials such as filaments or mats, and hygiene products comprising such materials are also described.

Composite particles that are biodegradable and easy to handle while maintaining the characteristics of cellulose nanofibers, a method of producing composite particles, a dry powder containing the composite particles, and a skin application composition and a method of producing the skin application composition. A composite particle contains at least one type of particle and fine cellulose with which at least part of a surface of the particle is coated, wherein the particle and the fine cellulose are inseparable.

It is an object of the present invention to provide a resin composite comprising ultrafine cellulose fibers, in which deterioration of a resin component is suppressed. The present invention relates to a cellulose fiber-containing resin composition comprising cellulose fibers with a fiber width of 1000 nm or less having phosphoric acid groups or phosphoric acid group-derived substituents, and a resin, wherein the counterions of the phosphoric acid groups or phosphoric acid group-derived substituents are organic onium ions, and the conjugate bases of the organic onium ions have a pKb value of 1.0 or more.

The present invention is intended to provide a resin composition capable of suppressing separation between ultrafine cellulose fibers and a resin, and also capable of forming a film having excellent adhesiveness to a base material. The present invention relates to a method for producing a cellulose fiber-containing film, comprising: mixing cellulose fibers having a fiber width of 1000 nm or less with organic onium; mixing the cellulose fiber mixture obtained in the mixing step, an organic solvent and a resin to obtain a resin composition; and applying the resin composition onto a base material, wherein the cellulose fibers have anionic groups, and the content of the anionic groups is 0.50 mmol/g or more, and the content of the cellulose fibers in the resin composition is 1% by mass or more.