Method for evaluating cellulose nanofiber dispersion

Abstract

Herein provided are methods for evaluating cellulose nanofiber dispersions, comprising the steps of: (1) preparing a cellulose nanofiber dispersion; (2) adding a color material into the cellulose nanofiber dispersion; and (3) observing the cellulose nanofiber dispersion to which a colored pigment has been added with a light microscope. The methods allow for easy evaluation of whether or not agglomerates of cellulose nanofibers exist in cellulose nanofiber dispersions, which cannot be visually determined.

1 - 8 . (canceled) 
     
     
         9 . A food containing a cellulose nanofiber dispersion wherein the cellulose nanofiber dispersion contains no agglomerates of cellulose nanofibers as evaluated by the following method:
 (1) preparing a cellulose nanofiber dispersion;   (2) adding a color pigment into the cellulose nanofiber dispersion; and   (3) observing the cellulose nanofiber dispersion to which the color pigment has been added with a light microscope to determine whether or not agglomerates of cellulose nanofibers exist in a cellulose nanofiber dispersion, which cannot be visually determined, wherein the colored pigment is less transparent to light during observation with a light microscope,   wherein the agglomerates have a size of 150 μm or more and cannot be visually determined.   
     
     
         10 . A cosmetic containing a cellulose nanofiber dispersion wherein the cellulose nanofiber dispersion contains no agglomerates of cellulose nanofibers as evaluated by the following method:
 (1) preparing a cellulose nanofiber dispersion;   (2) adding a color pigment into the cellulose nanofiber dispersion; and   (3) observing the cellulose nanofiber dispersion to which the color pigment has been added with a light microscope to determine whether or not agglomerates of cellulose nanofibers exist in a cellulose nanofiber dispersion, which cannot be visually determined, wherein the colored pigment is less transparent to light during observation with a light microscope, wherein the agglomerates have a size of 150 μm or more and cannot be visually determined.   
     
     
         11 . A rubber composition containing a cellulose nanofiber dispersion wherein the cellulose nanofiber dispersion contains no agglomerates of cellulose nanofibers as evaluated by the following method:
 (1) preparing a cellulose nanofiber dispersion;   (2) adding a color pigment into the cellulose nanofiber dispersion; and   (3) observing the cellulose nanofiber dispersion to which the color pigment has been added with a light microscope to determine whether or not agglomerates of cellulose nanofibers exist in a cellulose nanofiber dispersion, which cannot be visually determined, wherein the colored pigment is less transparent to light during observation with a light microscope, wherein the agglomerates have a size of 150 μm or more and cannot be visually determined.   
     
     
         12 . The food of  claim 9 , wherein the colored pigment has an average particle size of 10 μm or less. 
     
     
         13 . The food of  claim 9 , wherein the step (2) comprises adding a dispersion of a colored pigment to the cellulose nanofiber dispersion. 
     
     
         15 . The cosmetic of  claim 10 , wherein the colored pigment has an average particle size of 10 μm or less. 
     
     
         16 . The cosmetic of  claim 10 , wherein the step (2) comprises adding a dispersion of a colored pigment to the cellulose nanofiber dispersion. 
     
     
         17 . The rubber composition of  claim 11 , wherein the colored pigment has an average particle size of 10 μm or less. 
     
     
         18 . The rubber composition of  claim 11 , wherein the step (2) comprises adding a dispersion of a colored pigment to the cellulose nanofiber dispersion.