The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 29, 1977
Filed:
Mar. 05, 1976
Gerald W Chunat, Apple Valley, MN (US);
James E Maloney, Eagan, MN (US);
Economics Laboratory, Inc., St. Paul, MN (US);
Abstract
The disclosed foamable phosphatizing compositions comprise a phosphatizing agent combined with a high-foaming surfactant. When mixed with a gas such as air, the composition provides a relatively stable foam which adheres to overhead or inclined or vertical metal surfaces. When the foam has been in place on the metal surface for a certain minimum dwell time (and the coating weight has reached at least 10mg/ft.sup.2), the phosphatizing composition is rinsed off or is permitted to drain off. By procedures which involve reproducible laboratory tests, maximum and minimum dwell times or contact times can be determined even for use in the field under poorly controlled conditions. As a result, the control over the resulting phosphate coating weights is comparable to the control obtainable in immersion techniques or tunnel sprayer techniques. This high degree of control in a foam spraying technique makes possible an efficient, economical method for spray-phosphatizing bulky three-dimensional objects or inclined or overhead surfaces, regardless of whether or not reuse of the phosphatizing composition is a realistic possibility.