Disclosed is a film-forming solution comprising: a) Urea b) A film forming polymer c) A polar solvent d) A co-solvent e) A Plasticizer selected from diethyl phthalate, triethyl citrate, dibutyl sebacate, diethyl sebacate, dibutyl phthalate, acetyltriethyl citrate, and polyethylene glycols, and f) Water The solution is used for removing abnormal ungula keratinous material.