Method for producing micronized hydrophobically modified cellulose fiber

A method for producing a dispersion of fine hydrophobically modified cellulose fibers having an average fiber length of 1 μm or more and 1,000 μm or less comprising anionic group-containing anionically modified cellulose fibers bound to a modifying group, the method comprising:

• subjecting anionically modified cellulose fibers to a fiber shortening treatment, subsequently introducing the anionically modified cellulose fibers to a modifying group to produce hydrophobically modified cellulose fibers comprising anionic group-containing anionically modified cellulose fibers, and thereafter subjecting the hydrophobically modified cellulose fibers to a finely pulverizing treatment in an organic solvent to produce the fine hydrophobically modified cellulose fibers;
• wherein the fiber shortening treatment is a hydrothermal decomposition treatment.