A Lignin-Containing Cellulose Nanofiber， a Paper and a Film Comprising the Said Lignin-Containing Cellulose Nanofiber

The present invention relates to a lignin-containing cellulose nanofiber characterized in that (a) the said lignin-containing cellulose nanofiber has a content of carboxyl group in a range of 0.2-1.5 mmol/g， (b) the said lignin-containing cellulose nanofiber has Zeta potential in a range of ??100 to ??35 mV， and (c) the said lignin-containing cellulose nanofiber has an average diameter in a range of 3-30 nm. In addition， the present invention further relates to a paper and a film comprising the said lignin-containing cellulose nanofiber. The present invention also relates to a process for preparing a lignin-containing cellulose nanofiber comprising steps of (i) treating a lignin-containing cellulosic material with an organic solvent， (ii) treating the cellulosic material treated from the step (i) with derivative of N-oxy radical compound and hypochlorite compound， and (iii) mechanical treating the cellulosic material treated from the step (ii).