A dispersion liquid including a fiber material which is capable of forming a porous film having high porosity; a porous film formed using the dispersion liquid; a power storage element including the porous film; and a method for producing a porous film using the dispersion liquid. In the dispersion liquid including the fiber material and an organic solvent, which is used for forming a porous film by applying and drying, the fiber material contains a predetermined amount of a modified cellulose fiber including a carboxy group or a metal salt thereof, and the amount of water in the dispersion liquid is 5% by mass or less.

Disclosed is a dispersion of metal-containing oxidized cellulose nanofibers with superior dispersibility, which is applicable to various uses. The disclosed metal-containing oxidized cellulose nanofiber dispersion comprises a dispersion medium, and metal-containing oxidized cellulose nanofibers containing a metal other than sodium in salt form, wherein the metal-containing oxidized cellulose nanofibers have a number-average fiber diameter of 100 nm or less and an average degree of polymerization of 100 to 2,000.

The invention relates to a method for producing structurally coloured films, particles and interference pigments comprising cellulose nanocrystals, such as neutralised cellulose nanocrystals. The films and particles can be used as interference pigments or coloured particles such as glitters for various applications. The method comprises steps of depositing a nanocrystal suspension comprising cellulose nanocrystals onto a substrate: spreading the nanocrystal suspension across the substrate using a spreader: ageing the nanocrystal suspension to partially or completely recover the cholesteric structures lost during deposition and spreading: drying the deposited nanocrystal suspension so that the nanocrystals self-assemble to form a structurally coloured film: and annealing the structurally coloured film to increase the water resistance of the film. The structurally coloured film comprises nanocrystals which are organized into chiral nematic structures to provide the structural colour.

A process for producing porous cellulose beads of the present invention is characterized by comprising the steps of: a) mixing an alkali aqueous solution and cellulose to prepare cellulose micro dispersion at low temperature, b) adding water to the cellulose micro dispersion to prepare cellulose slurry, and d) bringing the cellulose slurry into contact with coagulation solvent. A carrier for ligand immobilization of the present invention is characterized by being by shrinking polysaccharide porous beads not less than 10% by a shrinkage rate defined by the following formula, and crosslinking the polysaccharide porous beads:
Shrinkage rate (%)=(1V.sub.2/V.sub.1)100
(wherein, V.sub.1 indicates the gel volume of polysaccharide porous beads before shrinkage, and V.sub.2 indicates the gel volume of polysaccharide porous beads after shrinkage).

It is an object of the present invention to provide a composite sheet, which achieves all of water repellency, water resistance, transparency and mechanical strength. The present invention relates to a sheet having a fiber layer and a coating layer on the fiber layer, wherein the fiber layer comprises ultrafine cellulose fibers having a fiber width of 1000 nm or less in an amount of 60% by mass or more, the haze of the sheet is 20% or less, and the water contact angle of the surface of the sheet on the side of the coating layer which is measured 30 seconds after completion of the dropping of distilled water is 70 degrees or more.

Disclosed herein is method for preparing a masterbatch by dispersing chemically modified cellulose nanofibers having carboxy groups under acidic conditions and then mixing the dispersed cellulose nanofibers with rubber latex. More specifically, the present disclosure provides a method for producing a masterbatch, including: (A) a step of introducing a carboxy group to a cellulose-based raw material to prepare a modified cellulose; (B) a step of carrying out defibration treatment and dispersion treatment of the modified cellulose to prepare a cellulose nanofiber; (C) a step of acidifying the cellulose nanofiber to prepare an acid type cellulose nanofiber, and (D) a step of mixing the acid type cellulose nanofiber and a rubber component. The rubber composition having excellent strength such as tensile strength can be provided by using the obtained masterbatch.

A dispersion liquid including a fiber material which is capable of forming a porous film having high porosity; a porous film formed using the dispersion liquid; a power storage element including the porous film; and a method for producing a porous film using the dispersion liquid. In the dispersion liquid including the fiber material and an organic solvent, which is used for forming a porous film by applying and drying, the fiber material contains a predetermined amount of a modified cellulose fiber including a carboxy group or a metal salt thereof, and the amount of water in the dispersion liquid is 5% by mass or less.

There is provided a use of a material comprising fibers as an oxygen barrier, wherein the fibers comprise native cellulose and dialcohol cellulose. There is also provided a material comprising fibers and having a density of at least 1200 kg/m.sup.3, wherein the fibers comprise native cellulose and dialcohol cellulose and the oxygen permeability of the material according to ASTM D3985 is below 30 ml.Math.?m/(m.sup.2.Math.kPa.Math.24 h) at 23? C. and 80% relative humidity.

According to an example aspect of the present invention, there is provided a method of improving the reactivity and processability of cellulose in order to utilize cheap and easily available raw material and obtain excellent performance for biomaterial manufacturing.

Water-retaining gel compositions, methods of making water-retaining gel compositions, and the uses thereof for enhancing soils, preparing plant growth media and facilitating the growth of plants therein are disclosed.