| abstract |
An aqueous acidic composition for treating metal surfaces, the composition including the following components:n a) at least one water soluble or water dispersable anionic polyelectrolyte; b) at least one organofunctional silane including one or more reactive functional groups selected from the group including amino, mercapto, methacryloxy, epoxy and vinyl; c) at least one water dispersible solid wax wherein the weight ratio between components a:b is in the range of 1:2 - 4:1 , based on dry matter; the weight ratio between components (a+b):c is in the range of 1:3 - 3:1 , based on dry matter, and wherein components a and b may be present—at least partially—as their graft reaction product. Another aspect is a treating method using this composition and use of the thus treated metal surface. |