| abstract |
A method of protecting machine-readable markings on the surfaces of articles consisting in applying to the machine-readable markings a thin layer of an amorphous fluoropolymer, which may be, i.a., a copolymer of perfluoro(1,3-dioxole) or of perfluoro(2,2-dimethyl-1,3-dioxole) with a fluoromonomer selected from a specifically recited group, especially, with tetrafluoroethylene; or a cyclic aliphatic homopolymer in which the repeating unit contains an aliphatic ring of 5-9 members at least two of the ring members being carbon atoms independently substituted either by fluorine atoms or by perfluoromethyl groups, at most two of the ring atoms being oxygen atoms, the remaining portions of the repeating units when present, being pefluoromethylene groups. |