Process for the application of thin,continuous phosphate layers on metal surfaces
Abstract
Abstract A PROCESS FOR THE APPLICATION OF CONTINUOUS PHOSPHATE COATINGS ON IRON, STELL AND ZINC SURFACES. THE LAYERS ARE OF A THICKNESS OF ONE MICRON OR LESS AND ARE OF PARTICULAR HARDNESS. THESE COATINGS ARE PRODUCED BY SPRAYING ON THE METAL SURFACES AN AQUEOUS SOLUTION CONTAINING, ASIDE FROM ZINC-, PHOSPHATE-AND NITRATE IONS, NO2-INS, WATER-SOLUBLE GLYCEROPHOSPHATE AND NONIONIC DETERGENTS, ALL IN PREDETERMINED AMOUNTS IN VERY NARROW LIMITS. FOR THE COATING OF ZINC SURFACES, AN ADDITION OF A FLUORO-COMPLEX IS OPPORTUNE. THE RATIO OF TOTAL ACID TO FREE ACID IS TO BE HELD AT 8 TO 12. IN THE PROCESS ACCORDING TO THE INVENTION, A PRETREATMENT, E.G., DEGREASING, NOT ONLY IS NOT REQUIRED BUT ACTUALLY MAY BE DELETERIOUS. PHOSPHATE LAYERS OF 0.5 MICRON READILY CANA BE ATTAINED.
Inventors
- 👤 Rudolf Wagenknecht
- 👤 Hans Gotta
- 👤 Brigitte Spei
- 👤 Karl-Heinz Gottwald
Bibliographic Details
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| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |