Concentrate for liquid coating composition for metal substrates
AssigneeDiamond Shamrock Corporation
InventorJon A. DERidder
Life of this patent
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Abstract
A coating composition is prepared, typically, from a liquid composition precursor component to which there is added a concentrate adapted for blending with such precursor component. The concentrate contains pulverulent metal and a very minor amount of water-soluble cellulose ether, while preferably further containing water-dispersible organic liquid. The precursor component is exemplified by a solution of an inorganic acid such as chromic acid in water.
Claims18
A composition concentrate, said concentrate being adapted for blending with a liquid coating composition precursor that contains water-soluble inorganic compound, with said concentrate providing excellent foam suppression during blending and thereafter forming a liquid coating composition for application to a metal substrate, said concentrate being chromate-free and containing:
- a. pulverulent metal flake;
- b. between about 0.1-3 weight percent, exclusive of liquid medium, of water-soluble cellulose ether;
- and having,
- c. water based liquid medium, containing water-dispersible organic liquid providing a weight ratio of said pulverulent metal flake to said organic liquid of from about 1:4 to about 4:1, and with said organic liquid being present in an amount sufficient to supply at least about 5 volume percent of said liquid to the total volume of said coating composition.
The method of preparing a liquid coating composition for application to a metal substrate, which method provides excellent foam suppresion during preparation and includes the steps of establishing a liquid precursor composition of water soluble inorganic compound in liquid medium, said compound providing chromium as a portion thereof, and said method thereafter including blending said precursor with a chromate-free composition concentrate containing pulverulent metal flake and between about 0.1-3 weight percent, exclusive of the concentrate liquid medium of water-soluble cellulose ether, said concentrate liquid medium being water based and containing water-dispersible organic liquid, wherein the resulting concentrate composition contains a weight ratio of the metallic flake to said organic liquid of between about 1:4-4:1, and with said organic liquid being present in an amount sufficient to supply at least about 5 volume percent of said liquid to the total volume of said coating composition.
In a liquid coating composition for application to a metal substrate for preparing an adherent, corrosion resistant coating thereon, which composition includes an intimate mixture in aqueous medium of water soluble inorganic compound providing chromium as a portion thereof, said aqueous medium containing 5-50 volume percent based on the total volume of the coating composition, of water-dispersible organic liquid that is a high boiling organic compound having a boiling point above 100.degree.C. at atmospheric pressure, with said coating composition further containing pulverulent metal, the improvement for suppressing foam formation during preparation wherein said composition also contains, in intimate mixture, below about 3 weight percent, basis total weight of said coating composition, of water-soluble cellulose ether.
The method of preparing a liquid coating composition of suppressed foam formation in preparation, which composition provides an adherent, corrosion resistant coating on a substrate, and includes an intimate mixture in aqueous medium of water soluble inorganic compound providing chromium as a portion thereof, said aqueous medium containing between about 5-50 volume percent, basis total volume of said coating composition, of water-dispersible organic liquid that is a high boiling organic compound having a boiling point above 100.degree.C. at atmospheric pressure, with said coating composition further containing pulverulent metal, which method for suppressing foam formation comprises blending into said composition during the preparation thereof below about 3 weight percent, basis total weight of said coating composition, of water-soluble cellulose ether.
Dependencies are inferred from the claim text.