Patent ID: 6989440

Claim:
A purified chitin having a total content of fatty acids and salts thereof not higher than 0.2 wt. % in terms of fatty acids, wherein the chitin is a chemically modified chitin, chitosan, chemically modified chitosan, decomposition product of chitin, or decomposition product of chitosan wherein the said decomposition is carried out by acid hydrolysis or oxidation or by enzyme and the fatty acids are free fatty acids, metal ion salts of free fatty acids, calcium salt of free fatty acid, or magnesium salt of free fatty acid, wherein said fatty acids and salts thereof comprise at least one fatty acid or a salt thereof selected from the group consisting of palmitic acid, oleic acid, stearic acid and myristic acid and salts thereof; and wherein the purified chitin is not D-glucosamine, wherein said chitin is chitosan having a purity such that an aqueous chitosan solution with said chitosan dissolved at a concentration of 0.5 wt. % in a 0.5 wt. % aqueous solution of acetic acid has a transparency of at least 20 as measured in accordance with the method described in “9 Clarity” of the Industrial Effluent Testing Method stipulated under K 0102 (1998) in Japanese Industrial Standards (JIS).