Primer for coatings containing fluorocarbon polymers with an amount of poly(arylene sulfide) resin, aromatic polyether sulfone resin or aromatic polyether ketone resin, and use thereof

摘要

A primer coating composition which is particularly suitable for topcoating with fluorocarbon polymers is described, this primer composition contains (a) 100 parts by weight of a copolymer of tetrafluoroethylene, perfluoro(alkylvinyl) ethers and if appropriate hexafluoropropylene or vinylidene fluoride, (b) 10 to 250 parts by weight of a mixture of lithium hydroxide and finely divided silicon dioxide produced by thermal treatment, (c) 10 to 1000 parts by weight of at least one thermoplastic resin from the group comprising the polyarylene sulfide resins, the aromatic polyether-sulfone resins and the aromatic polyether-ketone resins and (d) water as a liquid carrier. Up to 80 parts by weight of component (a) can, if appropriate, be replaced by dispersed polytetrafluoroethylene particles. The primer composition is especially suitable for application on articles with uneven surfaces, since it is sufficiently adhesion-promoting even in relatively thick layers. It is used for coating both metallic and non-metallic substrates, and a topcoat of a fluorocarbon polymer is subsequently applied, without intermediate heat treatment being necessary.