Abstract: An improved electrodepositable composition is provided comprising: (a) an active hydrogen-containing cationic resin electrodepositable on a cathode; (b) a capped polyisocyanate curing agent; and (c) an organotin-containing catalyst. The improvement comprises the addition to the electrodepositable composition of a water immiscible acid functional compound having a hydrocarbon chain of at least 5 carbon atoms. The composition provides improved cure response and appearance properties when electrodeposited over conductive substrates.

Abstract: An electrodepositable composition is provided comprising:(A) a non-gelled cationic resin which is derived from a polyepoxide and which contains in the resin molecule cationic salt groups and active hydrogen groups selected from aliphatic hydroxyl and primary and secondary amino; and present as a separate component(B) a fully capped polyisocyanate curing agent containing substantially no free isocyanate groups. The electrodepositable composition contains from about 0.02 to 1.0 milliequivalents phenolic hydroxyl groups per gram of resin solids, and from about 0.1 to 2.0 milliequivalents beta-hydroxy ester groups per gram of resin solids. The composition provides excellent corrosion resistance when electrodeposited over steel substrates, and does not require lead in the formulation nor the use of a conventional chrome rinse for the steel substrate pretreatment before electrodeposition.

Abstract: An electrodepositable composition is provided comprising:(A) a non-gelled cationic resin which is derived from a polyepoxide and which contains in the resin molecule cationic salt groups and active hydrogen groups selected from aliphatic hydroxyl and primary and secondary amino; and present as a separate component(B) a fully capped polyisocyanate curing agent containing substantially no free isocyanate groups, The electrodepositable composition contains from about 0.02 to 1.0 milliequivalents phenolic hydroxyl groups per gram of resin solids, and from about 0.1 to 2.0 milliequivalents beta-hydroxy ester groups per gram of resin solids. The composition provides excellent corrosion resistance when electrodeposited over steel substrates, and does not require lead in the formulation nor the use of a conventional chrome rinse for the steel substrate pretreatment before electrodeposition.

Abstract: Electrodepositable primer compositions comprising an aqueous dispersion of an ionic epoxy-based resin, a hindered amine light stabilizer and an antioxidant mixture which comprises a phenolic antioxidant and a sulfur-containing antioxidant. The primer compositions find particular use under topcoats which are permeable to UV radiation which, in the absence of the hindered amine and antioxidant mixture, causes delamination of the topcoat from the primer coat.

Abstract: Electrodepositable compositions comprising active hydrogen-containing ionic resins, capped polyisocyanate curing agents and triorganotin catalysts are disclosed. The catalysts are liquid, can be easily incorporated into the electrodepositable compositions and surprisingly exhibit good catalytic activity at low levels.

Abstract: An additive for cationic electrodepositable coating compositions is disclosed which improves hiding ability, stability, rheology and oil spot resistance. The additive is present in amounts of between 0.5 to 40 weight percent and is prepared by polymerizing in aqueous medium, under free radically initiated conditions, an aqueous dispersion of a polymerizable, ethylenically unsaturated monomer composition in the presence of a cationic polymeric surface active substance. The coating composition additionally has between 60 to 99.5 weight percent of a cationic salt group containing film forming polymer. Also disclosed is a method for coating which includes electrodepositing the above composition on an electrically conductive cathode.