abstract |
Process for producing novel water-base coating compositions and for applying such compositions to metal surfaces to render them corrosion-resistant, comprising reacting an epoxy trialkoxy silane with a primary aminotrialkoxy silane in a molar ratio providing one epoxy group for reaction with each primary amino hydrogen to form a hydrolyzable siloxane precursor coating composition which is solubilized, such as by the presence of a volatile organic weak acid and hydrolyzing said precursor compound in situ on a metallic surface to form a silanol precursor compound which is bonded to a metallic surface and is simultaneously cross-linked with itself and/or with external crosslinking agents under dehydration conditions to form a corrosion-resistant conversion coating or bonding coating having exceptional durability. |