Method of producing silane-modified cationized cellulose

A method of producing silane-modified cationized cellulose, comprising:

• the step (1) of cationizing water-soluble cellulose ether in a presence of alkali in a mixed solvent of a water-compatible organic solvent and water to obtain slurry comprising cationized cellulose;
• the step (2) of adding acid to said slurry and neutralizing said alkali;
• the step (3) of reacting said cationized cellulose obtained after said neutralization with an aminosilane compound which is 0.3-10% by mass relative to an amount of water-soluble cellulose ether used as raw material of said cationized cellulose;
• and
• the step (4) of drying and powderizing a product obtained in the step (3), wherein
• drying is conducted in the step (4) at a temperature of 115-160° C. until weight loss on drying is 5% by weight or less, or
• further comprising the step (5) of adding a water-compatible organic solvent or a mixed solvent of a water-compatible organic solvent and water to said cationized cellulose obtained in the step (2) so that water content in a whole solvent that contacts said cationized cellulose is 10% by mass or less.