Process for inhibiting corrosion of metal and corrosion-inhibiting layer use therein
US4816303A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 1987 |
| Grant date | Mar 28, 1989 |
| Priority date | — |
| Expiry date | Jun 15, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31678
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Corrosion of ferrous metal and aluminum surfaces, in particular, is inhibited by a layer of an organic-metallic complex of a polyamine with a (i) metal oxide, or (ii) metallate ion, or (iii) water-soluble metallate salt, in aqueous systems having a pH greater than about 7. The polyamine contains at least four (4) amine groups, two of which are secondary amine groups. The effect of the N atoms stretched over the length of the polyamine produces a "caging effect"0 which immobilizes the oxide, or metallate ions, thus forming the protective layer. The organic-metallic complex deposited on the metal's surface forms the "amine-metallic" layer which may be either an "amine-metal oxide complex" which is a coordination complex, or, an "amine-metallate complex". The amine-metallate complex may be either an ionic complex of "amine.metallate ions", or, a mixture of the polyamine and metallate salt which mixture is not a complex, but in solution, behaves like one, and is therefore referred to as an admixture complex of an "amine+metallate salt". The organic-metallic complex may be present in a concentration from about 10 ppm to about 5% by wt in neutral or basic aqueous solution. In the lower r…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.