N-chlorinated sulphonic acids of the formula ##STR1## (wherein R is group ##STR2## and their salts, particularly their sodium and potassium salts, are disclosed. These compounds are chlorine release agents and may be used as bleaching or germicidal agents either alone or in cleansing or detergent compositions. Preferred compounds are those wherein R is a group ##STR3## in the form of their sodium or potassium salts.