An organic fluorine compound of the formula:
wherein X represents an isocyanato, optionally substituted amino or optionally substituted amido group;
R¹ represents hydrogen or an optionally substituted alkyl radical;
R² represents hydrogen or an alkyl radical;
Y represents F and Z represents F, Cl or CF₃ or Y and Z together form a ―(CF₂) chain wherein m represents an integer from 2 to 4, and
n represents a positive integer which must be 1 when Z is C or CF₃.