Benzenesulfonic acid,3-[(2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluorononyl)oxy]-4-[2-[(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)oxy]ethoxy]-