The present invention is directed towards an electrodepositable coating composition comprising a polybutylene oxide polymer, an ionic film-forming polymer having functional groups, and a curing agent that is reactive with functional groups on the film-forming polymer. Also disclosed are methods of making the electrodepositable coating composition. Also disclosed are substrates treated with the electrodepositable coating composition.

An electrocoating composition and a coating formed from the composition are described herein. The electrocoating composition includes at least an epoxy resin component, an isocyanate-functional component and a silica-based additive. The coating shows about 40 to 70% reduction in edge corrosion relative to a conventional coating.

An epoxy resin emulsion includes a continuous phase including an aqueous carrier and an acid. The emulsion also includes a dispersed phase including an epoxy resin. The epoxy resin is the reaction product of an amine compound and a first epoxy reactant. The first epoxy reactant itself includes the reaction product of (1) an aromatic diol monomer, (2) a di-glycidyl ether of Bisphenol A and/or a di-glycidyl ether of catechol, and (3) a C8-C18 alkyl phenolic end-capping agent. The (1) aromatic diol monomer has the structure: ##STR00001##
In this structure, each of R.sup.1-R.sup.4 is independently a hydrogen atom, a C.sub.1-C.sub.8 alkyl group, a C.sub.3-C.sub.8 cycloalkyl group, an aryl group, an aralkyl group, a halide group, a cyano group, a nitro group, a blocked isocyanate group, or a C.sub.1-C.sub.8 alkyloxy group or wherein any two or more of R.sup.1-R.sup.4 may be a fused ring.

A method of treating the surface of a metal base which is conducted prior to cationic electrodeposition coating and is used for improving throwing power in the cationic electrodeposition coating; a metallic material treated by the surface treatment method; and a method of coating this metallic material.

A coated metal alloy substrate, a process for producing a coating a metal alloy substrate, and an electronic device having a housing comprising a coated metal alloy substrate are described. The coated metal alloy substrate comprises a passivation layer deposited on the metal alloy substrate, a porous conductive water borne carbon nanotube layer on the passivation layer, and an electrophoretic deposition layer deposited on the porous conductive water borne carbon nanotube layer.

It is an object of the present invention is to provide an electrodeposition coating composition and an electrodeposition coating method that enable the formation of a cured electrodeposition coating film that develops excellent throwing power and exhibits a good appearance. An electrodeposition coating composition of the present invention comprising: at least one compound (A) selected from the group consisting of a zinc compound (A-1) and a bismuth compound (A-2); an aminated resin (B); and a curing agent (C), wherein a milligram equivalent (MEQ (A)) of an acid per 100 g of a resin solid content in the composition is 27 or more; a coulombic efficiency of the composition is 30 mg/C or less; a film resistance of a 15-μm-thick uncured electrodeposition coating film formed using the composition is 400 kΩ.Math.cm.sup.2 or more; and a coating film viscosity of an electrodeposition coating film obtained from the composition is 3000 Pa.Math.s or less at 50° C.

Aqueous cathodic electrocoat compositions with improved edge protection and methods for preparing such electrocoat compositions are described herein. In an exemplary embodiment, an electrocoat composition includes water; a crosslinkable resin comprising a binder of an epoxy-amine adduct and a crosslinking agent; a neutralizing agent for neutralizing the epoxy amine adduct, wherein the neutralizing agent has a pKa value of greater than 0; and a pigment paste. The pigment paste may comprise silica, barium sulfate or silica and barium sulfate.

An epoxy resin emulsion includes a continuous phase including an aqueous carrier and an acid. The emulsion also includes a dispersed phase including an epoxy resin. The epoxy resin is the reaction product of an amine compound and a first epoxy reactant. The first epoxy reactant itself includes the reaction product of (1) an aromatic diol monomer, (2) a di-glycidyl ether of Bisphenol A and/or a di-glycidyl ether of catechol, and (3) a C8-C18 alkyl phenolic end-capping agent. The (1) aromatic diol monomer has the structure:

##STR00001##

In this structure, each of R.sup.1-R.sup.4 is independently a hydrogen atom, a C.sub.1-C.sub.8 alkyl group, a C.sub.3-C.sub.8 cycloalkyl group, an aryl group, an aralkyl group, a halide group, a cyano group, a nitro group, a blocked isocyanate group, or a C.sub.1-C.sub.8 alkyloxy group or wherein any two or more of R.sup.1-R.sup.4 may be a fused ring.

The process for coating a guide comprises at least the steps of: supplying a guide (1) made of metallic material and comprising an outer surface (2, 3) provided with a first portion (2) adapted to slide a carriage (4) and a second portion (3) separate from the first portion (2); depositing a first coating layer (9) on the first portion (2) and on the second portion (3); cataphoretic painting the guide (1) adapted to deposit a second coating layer (12) onto the first portion (2) and onto the second portion (3) on top of the first coating layer (9); and removing the second coating layer (12) from the first portion (2).

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.