Water-borne cationic binders for wash primers

摘要

An aqueous mixture AB comprising, in its solids, a mass fraction of from 5 % to 40 % of a polyvinyl butyral B , and a mass fraction of from 60 % to 95 % of a Mannich base A which is made by a two-step reaction wherein an epoxy amine adduct A1 prepared in the first step from an epoxy resin A11 with a mixture A12 of a primary linear or branched aliphatic amine A121 having from 2 to 30 carbon atoms and a further aliphatic linear, branched or cyclic amine A122 having from 4 to 16 carbon atoms and having one primary and at least one tertiary amino group, which epoxy amine adduct A1 is reacted in the second step with formaldehyde and a phenolic compound A2 to form a Mannich base, and a method of use thereof as a binder in wash primers