A method for pretreating and dyeing cellulose (2), comprising the steps of: providing a cellulose (2), carrying out a cationization reaction and carrying out a bleaching reaction by means of a bleaching agent, wherein the bleaching agent is stabilized by means of at least one stabilizer.

A fibrous cellulose-containing material capable of significantly improving resin strength and a method of preparation thereof, as well as a fibrous cellulose composite resin excellent in strength. The fibrous cellulose-containing material contains fibrous cellulose which is a carbamate-modified microfiber cellulose having hydroxyl groups, part or all of which are substituted with carbamate groups, and having an average fiber width of not smaller than 0.1 μm, and contains powder that is non-interactive with the fibrous cellulose. The fibrous cellulose composite resin contains fibrous cellulose which is the above-mentioned fibrous cellulose-containing material, and part or all of the resin is powdered resin. The method for preparing a fibrous cellulose-containing material includes adding at least either of powder that is non-interactive with fibrous cellulose and a dispersion thereof, to a dispersion of carbamate-modified microfiber cellulose to obtain a mixed liquid, and removing the dispersion medium from the mixed liquid.

The invention relates to [1] a cellulose fiber composite excellent in dispersion stability, in which at least one amine selected from a polyamine and a monoamine having a reactive functional group bonds to anion-modified cellulose fibers, and which satisfies at least one of amine introduction ratio of 60% or less (requirement 1) and average polymerization degree of anion-modified cellulose fibers of 300 or less (requirement 2), [2] a dispersion in which the cellulose fiber composite is dispersed in a medium, [3] a resin composition produced by blending the cellulose fiber composite and a resin, [4] a molded article produced by molding the cellulose fiber composite or the resin composition, and [5] a method for producing the cellulose fiber composite.

The invention relates to [1] a cellulose fiber composite excellent in dispersion stability, in which at least one amine selected from a polyamine and a monoamine having a reactive functional group bonds to anion-modified cellulose fibers, and which satisfies at least one of amine introduction ratio of 60% or less (requirement 1) and average polymerization degree of anion-modified cellulose fibers of 300 or less (requirement 2), [2] a dispersion in which the cellulose fiber composite is dispersed in a medium, [3] a resin composition produced by blending the cellulose fiber composite and a resin, [4] a molded article produced by molding the cellulose fiber composite or the resin composition, and [5] a method for producing the cellulose fiber composite.

A fibrous cellulose has an average fiber width of 0.1 .Math.m or more and has a part or all of hydroxyl groups replaced with carbamate groups, in which a replacement ratio with the carbamate group is 1.0 mmol/g or more, and a fine ratio is 30% or more. A fibrous cellulose composite resin contains a fibrous cellulose and a resin, and the above fibrous cellulose In manufacturing fibrous cellulose, a cellulose raw material and urea or the like are subjected to a heat treatment to replace a part or all of hydroxyl groups of the cellulose raw material with carbamate groups, defibration is performed within a range in which an average fiber width is 0.1 .Math.m or more, the heat treatment is performed such that a replacement ratio with the carbamate group is 1.0 mmol/g or more, and the defibration is performed until a fine ratio reaches 30% or more.

A fibrous cellulose has an average fiber width of 0.1 .Math.m or more and has a part or all of hydroxyl groups replaced with carbamate groups, in which a replacement ratio with the carbamate group is 1.0 mmol/g or more, and a fine ratio is 30% or more. A fibrous cellulose composite resin contains a fibrous cellulose and a resin, and the above fibrous cellulose In manufacturing fibrous cellulose, a cellulose raw material and urea or the like are subjected to a heat treatment to replace a part or all of hydroxyl groups of the cellulose raw material with carbamate groups, defibration is performed within a range in which an average fiber width is 0.1 .Math.m or more, the heat treatment is performed such that a replacement ratio with the carbamate group is 1.0 mmol/g or more, and the defibration is performed until a fine ratio reaches 30% or more.

A method for preparing a modified cellulose aerogel for glycoprotein separation is provided. In this method, cellulose aerogel is employed as a substrate. The cellulose aerogel is known to have a three-dimensional network structure with extremely high porosity and specific surface area and extremely low density. So, by using the cellulose aerogel as a substrate, it is possible to provide the glycoproteins to be separated with more binding sites. PEI dendrimer has abundant functional groups and can easily be modified. By modifying the cellulose aerogel substrate with the PEI dendrimer, it is possible to improve the density of the phenylboronic acid bound to the substrate, thereby leading to higher affinity toward the glycoproteins to be separated.

A method for preparing a modified cellulose aerogel for glycoprotein separation is provided. In this method, cellulose aerogel is employed as a substrate. The cellulose aerogel is known to have a three-dimensional network structure with extremely high porosity and specific surface area and extremely low density. So, by using the cellulose aerogel as a substrate, it is possible to provide the glycoproteins to be separated with more binding sites. PEI dendrimer has abundant functional groups and can easily be modified. By modifying the cellulose aerogel substrate with the PEI dendrimer, it is possible to improve the density of the phenylboronic acid bound to the substrate, thereby leading to higher affinity toward the glycoproteins to be separated.

The present invention relates to an adhesive composition containing (a) modified cellulose fibers having a cellulose I crystal structure, an average fiber length of 1000 nm or less, and an average fiber diameter of 1 nm or more and 300 nm or less; and (b) a resin. According to the present invention, an adhesive composition having excellent mechanical strength such as shearing adhesive strength can be provided. The adhesive composition of the present invention described above can be utilized in structural adhesion of vehicle assembly products and the like.

Provided are: a fine cellulose fiber that is superior in handling properties and that can suitably be used as a reinforcing material or the like for resin; a production method of the fine cellulose fiber; and a slurry and a composite comprising the fine cellulose fibers. The present invention pertains to fine cellulose fibers comprising a carbamate group. The degree of substitution with the carbamate group with respect to hydroxy groups in the fine cellulose fibers is preferably no less than 0.05 and no greater than 0.5. The present invention pertains to a slurry comprising the fine cellulose fibers, to a composite comprising the fine cellulose fibers and a resin, and to a production method of the fine cellulose fibers, comprising performing a heat treatment on a mixture of a plant raw material and urea or the like, and performing a miniaturization treatment of the plant raw material.