Nippon Paper Industries Co., Ltd.

Aikawa Iron Works Co., Ltd.

Tomoaki Koyanagi

Yoshihiko Aikawa

Shoichi Miyawaki

Shiho Tsuji

Masahiko Fukazawa

Tatsumi Hosaka

Minoru Ishida

Masami Kashibo

Munetaka Sonoda

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).

Method for producing cellulose nanofibers

A flotation apparatus F includes a tankfor receiving a liquid raw material, and introduces air into the tankto generate bubbles for adsorbing print ink in the liquid raw material to the bubbles, thereby floating and separating the print ink. The flotation apparatus F includes a circulating device for circulating the liquid raw material by raising and then lowering the liquid raw material in the tank, an air supply tubefor supplying air into the tank, and an agitating memberprovided in the tankfor taking the air from the air supply tubeand agitating the air for forming the air into fine bubbles. The agitating memberhas a rotary shaftheld horizontally and a plurality of membershorizontally separately provided around an outer periphery. On a cross section transverse to a longitudinal direction of the tank, an outer periphery of the agitating memberis arranged on a lower side of the tankand in a position at a downstream side of the liquid raw material relative to a vertical line V passing through a center of the tank

Flotation apparatus

Growing community of inventors

Tokyo, Japan

Tomoaki Koyanagi