Patent ID: 7229503

Claim:
A process of easy washings of glass substrates for multiple washing cycles, said process comprising: (A) coating a glass surface with a composition consisting essentially of a mixture of formulas (I) and (II): R f —CFY-L-W (I) W-L-YFC—O—R f —CFY-L-W (II) wherein: L is a linking organic group —CO—NR′—(CH 2 ) q —, with R′=H or C 1 -C 4 alkyl; q is an integer comprised between 1 and 8; Y=F, CF 3 ; W is a —Si(R 1 ) α (OR 2 ) 3−α group with α=0, 1, 2, R 1 and R 2 equal to or different from each other are C 1 -C 6 alkyl groups, optionally containing one or more ether O atoms, C 6 -C 10 aryl groups, C 7 -C 12 alkyl-aryl or aryl-alkyl groups; R f has a number average molecular weight in the range 350-5,000, and comprises repeating units having at least one of the following structures, randomly distributed in the chain: (CFXO),(CF 2 CF 2 O),(CF(CF 3 )CF 2 O),(CF 2 CF(CF 3 )O), wherein X=F, CF 3 ; wherein the structure (I) the end group of R f is of the T—O— type, wherein T is a (per)fluoroalkyl group selected from: —CF 3 , —C 2 F 5 , —C 3 F 7 , —CF 2 Cl, —C 2 F 4 Cl, —C 3 F 6 Cl; optionally one or two F atoms can be replaced by H; and wherein the admixture has a ratio by weight between the compound of structure (I) and that of structure (II) in the range 10:1-1:1; and (B) washing the coated glass surface with hot water or water and detergent.