English to French Law/Patents Engineering (general) carbon nanofibers

A carbon nanofiber having a content of oxygen generated by an oxidization treatment which is in a range of 8% by mass to 20% by mass, wherein the carbon nanofiber used in the oxidation treatment has 98 % or more color transmittance in toluene according to Section 6.2.4. of "Method of Testing Carbon Black for Rubbers" of JIS K 6221-1982, the content of oxygen is measured using an inert gas transportation and fusion infrared absorption method, and the oxidation treatment is carried out at 100 oc or higher using a mixed acid of nitric 15 acid and sulfuric acid in which the nitric acid concentration ratio is in the range of 10 % by mass to 30 % by mass.