For achieving the object of providing a method for the treatment of windshields to achieve an anti-fogging effect, compounds of the followig formula are contacted to the glass surface in an amount effective to impart fog resistant properties to the windshields: ##STR4## where a is 2 or 3; b is 0 or 1; c is 1 or 2; b+c is 1 or 2 and a +b +c is 4; R??? is Cl, Br, J or OR1, where R1 is an alkyl group