| abstract |
Dispersions comprising at least: n 0.1-30% by weight of a polytetrafluoroethylene or tetrafluoroethylene copolymers with other ethylenically unsaturated monomers; n 50-99% by weight of fluorinated liquid; n polar solvent (water and/or alcohol) complement to 100; n 0.01-5% by weight of surfactant selected from: n (a) nonionic hydrogenated or n (b) fluorinated, having a perfluoropolyether or perfluoroalkylic chain, both of ionic and non ionic type, selected from the following classes: n A') mono and dicarboxylic acid salts; n B') sulphonic acid salts; n C') phosphoric mono and diesters and their mixtures, as such or salified, optionally containing amounts of triesters lower than 15% by moles; n D') nonionic surfactants formed by fluorinated and polyoxyalkylenic chains with a number of oxyalkylenic repeating units higher than 6; n E') cationic surfactants having one or more fluorinated hydrophobic chains. |