Abstract: A weldable heat curable liquid coating composition for steel is provided that exhibits improved mar resistance without impairing the weldability characteristics of the coating. To this end, the composition contains a conductive welding aid of iron dust. The weldable coating when applied to steel and cured thereon to a dry film allows for spot welding of the coated steel without requiring special welding equipment and techniques.

Abstract: This invention relates to aqueous epoxy resin-containing compositions useful for depositing coatings on metallic substrates in order to protect substrates against corrosion. The aqueous compositions generally comprise (A) an organic resin component consisting essentially of at least one water-dispersible or emulsifiable epoxy resin; (B) a non-ionic emulsifier, (C) chromium trioxide, (D) a conductive pigment, (E) water, and, optionally, polytetrafluorethylene as a lubricant. The compositions may also contain phosphoric acid or an alkylphosphoric acid. These compositions are useful in coil coating operations to improve the electrocoatability of a metal substrate, in particular, steel, galvanized or aluminized substrates. The basecoated metal can then be conventionally coated or electro coated with weldable or non-weldable primer coatings and may be followed by the application of decorative topcoats.

Abstract: Coating composition especially useful for high gloss coating of untreated, bright, sealed, anodized metal substrates, particularly coils of such metal, comprises a catalyst-free composition comprising a high gloss, thermosetting, hydroxyl group-containing fluorocarbon polymer, a cross-linking agent comprising a blocked aliphatic polyisocyanate, a partially self-condensing, highly methylated melamine-formaldehyde resin or a mixture of the blocked polyisocyanate and melamine-formaldehyde resin, butanol solvent, an ultraviolet screening agent, an ultraviolet stabilizer acting as free radical scavenger, and optionally one or more of the following components: polysiloxane slip and flow and defoaming agents, a high boiling solvent distilling at a temperature of about 195.degree. C. or above to modify the viscosity of the composition and an amine active as an inhibitor for residual acid in the fluoropolymer.