The invention provides a method of improving the corrosion resistance of a metal substrate. The method comprises: (a) electrophoretically depositing on the substrate a curable electrodepositable coating composition to form a coating over at least a portion of the substrate, and (b) heating the substrate to a temperature and for a time sufficient to cure the coating on the substrate. The electrodepositable coating composition comprises a resinous phase dispersed in an aqueous medium, the resinous phase comprising: (1) an ungelled active hydrogen-containing, cationic salt group-containing resin electrodepositable on a cathode; (2) an at least partially blocked polyisocyanate curing agent; and (3) a pigment component comprising an inorganic, platelike pigment having an average equivalent spherical diameter of at least 0.2 microns. The electrodepositable coating composition demonstrates a pigment-to-binder ratio of at least 0.5. The coating composition contains less than 8 percent by weight of a grind vehicle.

A coating method for a cationic electrodeposition coating material includes steps for immersing a metal object to be coated in a first solution bath, a second solution bath and a third solution bath, and wherein: at least one step among the three steps is cationic electrodeposition coating that is accompanied by application of a current; a coating film which is formed through the three steps contains at least a base resin component (A), a reaction component (B) and a catalyst (C); and the first solution bath, the second solution bath and the third solution bath contain one or a combination of two of the base resin component (A), the reaction component (B) and the catalyst (C).

The invention provides an electrodepositable coating composition comprising a resinous phase dispersed in an aqueous medium, said resinous phase comprising: (1) an ungelled active hydrogen-containing, cationic salt group-containing resin; (2) an at least partially blocked polyisocyanate curing agent; and (3) a pigment component, wherein the pigment component comprises an inorganic, platelike pigment present in the resinous phase, wherein the electrodepositable coating composition contains less than 8 percent by weight of a grind vehicle, based on the total weight of solids in the electrodepositable coating composition. The invention also provides methods of improving the corrosion resistance of a metal substrate and coated substrates.

An object of the present invention is to find a method for producing a cationic electrodeposition coating composition that is excellent in storage stability, low-temperature curability, finished appearance, and corrosion resistance, and to provide a coated article excellent in these properties. The method for producing a cationic electrodeposition coating composition comprises mixing three components, i.e., an aqueous dispersion of an amino group-containing epoxy resin (A), an aqueous dispersion of a blocked polyisocyanate compound (B), and a pigment dispersion paste (C), wherein the aqueous dispersion of a blocked polyisocyanate compound (B) comprises a blocked polyisocyanate compound (b) and an emulsifier.

Electrodepositable coating compositions containing 1,1-di-activated vinyl compounds are described. The coating compositions produce cured coating layers that exhibit resistance to cratering. The coating compositions can be used in electrodepositable coating composition formulations.

The present disclosure is directed to an electrodepositable coating composition comprising a hydroxyl-functional addition polymer comprising constitutional units, at least 70% of which comprise formula (I): [C(R.sup.1).sub.2C(R.sup.1)(OH)] (I), wherein each R.sup.1 is independently one of hydrogen, an alkyl group, a substituted alkyl group, a cycloalkyl group, a substituted cycloalkyl group, an alkylcycloalkyl group, a substituted alkylcycloalkyl group, a cycloalkylalkyl group, a substituted cycloalkylalkyl group, an aryl group, a substituted aryl group, an alkylaryl group, a substituted alkylaryl group, a cycloalkylaryl group, a substituted cycloalkylaryl group, an arylalkyl group, a substituted arylalkyl group, an arylcycloalkyl group, or a substituted arylcycloalkyl group; an ionic salt group-containing film-forming polymer comprising active hydrogen functional groups; a blocked polyisocyanate curing agent comprising blocking groups, wherein the blocking groups comprise a 1,2-polyol as a blocking agent; and a bismuth catalyst.

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The present disclosure is directed to an electrodepositable coating composition comprising an electrodepositable binder comprising an ionic salt group-containing film-forming polymer and a curing agent; and at least one pigment: wherein the electrodepositable coating composition has a resin solids content of less than 30% by weight, based on the total weight of the electrodepositable coating composition, and a viscosity of at least 15 cP at a shear rate of 0.1/s, as measured by the BATH VISCOSITY TEST METHOD; and wherein the pigment optionally comprises a phyllosilicate pigment, and the pigment-to-binder ratio of the phyllosilicate pigment to the electrodepositable binder is less than 0.2:1 if the electrodepositable coating composition is a cationic electrodepositable coating composition and a pigment dispersing acid is present in the cationic electrodepositable coating composition. Also disclosed are coatings, coated substrates, and methods of coating a substrate.

The present disclosure is directed to a system for coating a metal substrate comprising an anionic electrodepositable coating composition comprising a film-forming binder comprising an anionic salt group-containing film-forming polymer and a curing agent, wherein the anionic salt group-containing film-forming polymer does not include carbamate functional groups if the anionic salt group-containing film-forming polymer is a phosphatized epoxy resin; and a non-electrodepositable coating composition comprising a corrosion inhibitor comprising an azole. Also disclosed are methods of coating metal substrates and multi-layered coated metal substrates.

An electrocoating composition is provided herein. The electrocoating composition includes an aqueous carrier. The electrocoating composition further includes a film forming binder. The film forming binder includes an epoxy-amine adduct and a blocked polyisocyanate crosslinking agent. The electrocoating composition further includes an anti-crater agent selected from the group of a polyester resin dispersion, a polyacrylate resin dispersion, and a combination thereof. The electrocoating composition further includes a supplemental anti-crater agent including a polyether modified polysiloxane.

The present disclosure is directed to an electrodepositable coating composition comprising (a) an active hydrogen-containing, ionic salt group-containing film-forming polymer: (b) an at least partially blocked polyisocyanate curing agent: (c) a curing catalyst; and (d) an edge control additive: wherein the electrodepositable coating composition has a gel point of less than 150? C. as measured by the GEL POINT TEST METHOD, an edge coverage of greater than 20%, as measured by the EDGE COVERAGE TEST METHOD, and an Ra of no more than 0.45, as measured by the SURFACE ROUGHNESS TEST METHOD. Also disclosed are methods of coating substrates, coatings, and coated substrates.