NANOCELLULOSE FIBER MANUFACTURING METHOD AND NANOCELLULOSE FIBER

The present invention relates to a method for producing nanocellulose fibers and to nanocellulose fibers， comprising: a pulp solution manufacturing step (S100) of preparing a suspension using cellulose fibers as a raw material; Wet grinding step of grinding the cellulose fibers in the suspension twice (S200); A drying step (S300) of freeze-drying the suspension to obtain a solid sheet-like nanocellulose fiber; And a powder forming step (S400) of pulverizing the solid sheet form to obtain nanocellulose fibers in a solid powder form. The cellulose fibers in the suspension used in the pulp solution manufacturing step (S100) include a raw material in which hardwood bleached pulp and softwood bleached pulp are mixed in a weight ratio of 8:2 or 7:3， and the wet grinding step (S200) includes the In-line milling step of mechanically pulverizing the cellulose fibers in the suspension to convert them into micro-cellulose fibers (S210); And a colloidal milling step (S220) of mechanically pulverizing the microcellulose fibers in the suspension to convert them into nanocellulose fibers. According to the present invention， a process consisting of two steps of in-line milling and colloid milling is carried out to reduce the process time to nano-ize cellulose， thereby increasing production efficiency. In addition， since the pulp， which is a raw material for cellulose fibers， is used by mixing hardwood bleached pulp and softwood bleached pulp， it is economical and easy to process compared to using only one type of pulp.