Process for producing iron phosphate coatings at ambient temperature
AssigneeIntex Products, Inc.
InventorsJ. Arthur Saus, Larry P. McCartney
Life of this patent
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Abstract
This invention relates to a process and composition for producing an iron phosphate conversion coating on a ferrous metal surface at ambient temperatures of from about 50.degree. F. to about 100.degree. F. The ferrous metal surface is contacted with an aqueous acidic phosphating solution having a pH within the range of 3 to 6 and consisting essentially of orthophosphate ions at a concentration of at least about 2.0 grams per liter and an ambient temperature activator comprising nitrite ions at a concentration of at least 0.08 grams per liter.
Claims13
A process for forming an iron phosphate conversion coating on a ferrous metal surface at ambient temperature, said process comprising applying at a temperature of from about 50.degree. F. to about 100.degree. F. to a ferrous metal surface an aqueous acidic phosphating solution having a pH within the range of 3 to 6 and comprising a source of phosphate consisting essentially of orthophosphate ions at a concentration of at least about 2.0 grams per liter and an ambient temperature activator comprising nitrite ions at a concentration of at least 0.08 grams per liter.
A process for forming an iron phosphate conversion coating on a ferrous metal surface at ambient temperature, said process comprising applying at a temperature of from about 50.degree. F. to about 100.degree. F. to a ferrous metal surface an aqueous acidic phosphating solution having a pH within the range of 3 to 4.7 and comprising a source of phosphate consisting essentially of orthophosphate ions at a concentration of about 5.0 to about 50 grams per liter and an ambient temperature activator comprising nitrite ions at a concentration of 0.1 to 10 grams per liter.
A process for forming an iron phosphate conversion coating on a ferrous metal surfacce at ambient temperature, said process comprising applying at a temperature of from about 50.degree. F. to about 100.degree. F. to a ferrous metal surface an aqueous acidic phosphating solution having a pH within the range of 3 to 4.7 and comprising a source of phosphate consisting essentially of orthophosphate ions at a concentration of about 5.0 to about 50 grams per liter, an ambient temperature activator comprising nitrite ions at a concentration of 0.1 to 10 grams per liter, and a cleaning agent.
Dependencies are inferred from the claim text.