Producing protective coatings on metal
Abstract
Abstract The process for the production of a protectively coated metal object which comprises applying to said metal object at least one condensable phosphate selected from the group consisting of alkali metal hydrogen phosphates and alkali metal ammonium phosphates and thereafter heating said object to a temperature above about 400*C whereby said phosphate undergoes condensation to produce a glass-like protective coating. The metal object, which may be bright or freshly surface-oxidized, is preferably iron or an iron alloy and the phosphate preferably is of the formula MenX2PnO(3n 1) IN WHICH EACH X is a hydrogen or ammonium ion, N IS AN INTEGER, Me is an alkali metal ion which, when n is 4 or more, may be partially replaced by a hydrogen, ammonium or equivalent of a polyvalent metal ion.
Inventors
- 👤 Joachim Marx
Bibliographic Details
Claims Analysis
Total Claims: 12References Cited (Backward Citations)
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