Abstract: An object of present invention is to provide a method for easily extracting and efficiently recovering xylan from wood. A xylan-containing material is produced by a method comprising steps of: (a) adding an acid and/or carbon dioxide to a black liquor discharged during a soda cooking step of wood chips including hardwood chips to adjust the pH of the black liquor to be in the range of 1 to 9, thereby giving a suspension; (b) dehydrating and washing an insoluble matter generated in the suspension to separately collect the insoluble matter; and (c) adding an organic solvent to the insoluble matter obtained at the step (b) to give a suspension, and separately collecting a xylan-containing material made of the insoluble matter present in the suspension by solid/liquid separation.

Abstract: An object of the present invention is to provide a method for easily extracting and efficiently recovering xylan from wood. A xylan-containing material is produced by a method comprising the steps of: (a) adding an acid and/or carbon dioxide to a black liquor discharged during a soda cooking step of wood chips including hardwood chips to adjust the pH of the black liquor to be in the range of 1 to 9, thereby giving a suspension; (b) dehydrating and washing an insoluble matter generated in the suspension to separately collect the insoluble matter; and (c) adding an organic solvent to the insoluble matter obtained at the step (b) to give a suspension, and separately collecting a xylan-containing material made of the insoluble matter present in the suspension by solid/liquid separation.

Abstract: Provided is a method which is capable of producing a cellulose nanofiber dispersion liquid that has a low viscosity and excellent fluidity even at a high concentration, while exhibiting excellent transparency. In a method for producing cellulose nanofibers, wherein a cellulosic starting material is oxidized in water using an oxidant in the presence of an N-oxyl compound and a compound that is selected from the group consisting of a bromide, an iodide and a mixture thereof and the thus obtained oxidized cellulose is defibrated and dispersed, pulp which is obtained by carrying out kraft cooking after a hydrolysis process is used as the cellulosic starting material.

Abstract: New cellulose nanofibers having a number average fiber length of 250 nm or lower, and a number average fiber diameter of 2 to 5 nm. These cellulose nanofibers provide a cellulose nanofiber dispersion that has a low viscosity even at a high concentration.

Abstract: Cellulose nanofibers are produced by means of a method comprising a step (A) of oxidizing a cellulosic starting material in the presence of an N-oxyl compound and a step (B) of forming the oxidized cellulosic starting material into nanofibers by defibrating the oxidized cellulosic starting material, and a step (C) of performing at least one selected from the following steps: a step (C-1) of treating the cellulosic starting material in water having a hydroxide ion concentration of 0.75 to 3.75 mol/L prior to performing the step (A); and a step (C-2) of subjecting the oxidized cellulosic starting material obtained from the step (A) to hydrolysis in an alkaline solution having a pH between 8 and 14 after performing the step (A) and prior to performing the step (B).

Abstract: Provided is a method which comprises a process of having an anion-modified cellulose nanofiber dispersion contain monovalent or divalent metal ions. Consequently, the fluidity of an anion-modified cellulose nanofiber dispersion obtained thereby is improved.

Abstract: Provided is a method which is capable of producing a cellulose nanofiber dispersion liquid that has a low viscosity and excellent fluidity even at a high concentration, while exhibiting excellent transparency. In a method for producing cellulose nanofibers, wherein a cellulosic starting material is oxidized in water using an oxidant in the presence of an N-oxyl compound and a compound that is selected from the group consisting of a bromide, an iodide and a mixture thereof and the thus obtained oxidized cellulose is defibrated and dispersed, pulp which is obtained by carrying out kraft cooking after a hydrolysis process is used as the cellulosic starting material.

Abstract: Cellulose nanofibers are produced by means of a method comprising a step (A) of oxidizing a cellulosic starting material in the presence of an N-oxyl compound and a step (B) of forming the oxidized cellulosic starting material into nanofibers by defibrating the oxidized cellulosic starting material, and a step (C) of performing at least one selected from the following steps: a step (C-1) of treating the cellulosic starting material in water having a hydroxide ion concentration of 0.75 to 3.75 mol/L prior to performing the step (A); and a step (C-2) of subjecting the oxidized cellulosic starting material obtained from the step (A) to hydrolysis in an alkaline solution having a pH between 8 and 14 after performing the step (A) and prior to performing the step (B).