Abstract: Fibrous cellulose highly capable of reinforcing resins, fibrous cellulose composite resins with high strength, and a method for preparing fibrous cellulose highly capable of reinforcing resins. The fibrous cellulose has an average fiber width of ?0.1 ?m, and has hydroxyl groups partially/fully substituted with carbamate groups at the substitution rate of ?1.0 mmol/g, and has an average fiber length of >0.10 mm. This fibrous cellulose and a resin are contained in the composite resin. The method includes heat treating a cellulose raw material and urea or derivatives thereof to substitute part/all of the hydroxyl groups in the cellulose raw material with carbamate groups, and defibrating the raw material into an average fiber width of ?0.1 ?m, wherein the heat treating is performed so that the rate of carbamate-group-substitution is ?1.0 mmol/g and an average fiber length of the material is >0.10 mm.

Abstract: A fibrous cellulose has an average fiber width of 0.1 µm 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 µm 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.

Abstract: 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 ?m, 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.

Abstract: A method for manufacturing a fibrous cellulose having a high resin reinforcing effect and a method for manufacturing a fibrous cellulose composite resin having high strength. A method for manufacturing a fibrous cellulose includes: a step of subjecting a cellulose raw material and at least one of urea and a derivative of urea to a heat treatment to replace a part or all of hydroxyl groups of the cellulose raw material with carbamate groups; and a step of defibrating the cellulose raw material within a range in which an average fiber width is 0.1 ?m or more. The heat treatment is performed under a condition that organic acid ions are added in an amount of 0.001 mmol or more with respect to 1 g of the urea and the derivative of urea. In addition, a fibrous cellulose thus obtained and a resin are kneaded to manufacture a fibrous cellulose composite resin.

Abstract: A fibrous cellulose composite resin excellent in strength, and a method for producing the same. The fibrous cellulose composite resin includes microfiber cellulose, a resin, and an acid-modified resin, wherein the microfiber cellulose has hydroxyl groups, which are substituted with carbamate groups, and has been washed and defibrated into an average fiber width of 0.1 ?m or larger, in which the amount of the byproduct is 10% or less per 100 parts by mass of a carbamate-modified cellulose. The production method includes heat-treating a cellulose raw material and urea to obtain a carbamate-modified cellulose, washing the carbamate-modified cellulose, defibrating the carbamate-modified cellulose to obtain a dispersion of carbamate-modified microfiber cellulose having an average fiber width of 0.1 ?m or larger, mixing the dispersion and an acid-modified resin to obtain a material containing carbamate-modified microfiber cellulose, and kneading the material with a resin to obtain a composite resin.

Abstract: A cellulose fiber composite recycled resin having excellent strength, and a method for producing the same. The cellulose fiber composite recycled resin contains a recycled resin and a mixture of fibrous cellulose, at least one of resin powders and resin pellets, and at least one substance selected from the group consisting of phthalic acid, phthalates, derivatives of phthalic acid, and derivatives of phthalates. For producing this composite resin, at least one of resin powders and resin pellets are added to a slurry of cellulose fibers to obtain a first mixture, a recycled resin is mixed into the first mixture to obtain a second mixture, and the second mixture is kneaded, wherein part or all of the cellulose fibers are fine fibers.

Abstract: A fibrous cellulose composite resin being excellent in strength, a method for producing the same, and a reinforcing material for resins capable of significantly improving resin strength are provided. The fibrous cellulose composite resin includes fibrous cellulose containing microfiber cellulose, a resin, and an acid-modified resin, wherein the microfiber cellulose has an average fiber width of 0.1 ?m or larger, an average fiber length of 0.02 to 2.0 mm, and a percentage of fibrillation of 1.0% or higher, and hydroxyl groups substituted with carbamate groups, and the carbamate groups are ionically bonded to acidic groups of the acid-modified resin.

Abstract: To provide a fibrous cellulose composite resin having excellent strength, particularly excellent flexural modulus, and having no coloring problem, and a method for manufacturing the same. A fibrous cellulose composite resin contains: microfiber cellulose having an average fiber width of 0.1 ?m or more; a resin; and a polybasic acid salt. In addition, the raw material fibers are defibrated into microfiber cellulose within a range where the microfiber cellulose has an average fiber width of 0.1 ?m or more, and this microfiber cellulose, a resin, and a polybasic acid salt are kneaded to manufacture a fibrous cellulose composite resin.