Pickling solution
US3936316A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 29, 1972 |
| Grant date | Feb 3, 1976 |
| Priority date | — |
| Expiry date | Nov 29, 1992 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23G1/02
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The invention is for a process and composition for pickling metals, especially iron based metals, prior to metal finishing. A hydrohalide acid pickling solution is used which solution is characterized by the addition of urea. The urea substantially reduces, even completely eliminates, the excessive liberation of noxious and corrosive hydrohalide acid fumes normally associated with such pickling operations. This is an advantage as it greatly reduces the cost of the pickling operation as the consumption of acid is dramatically reduced. Moreover, there is less injury to personnel and equipment contacted with said fumes. Finally, a metal surface treated with the pickling solution of the invention is improved as there is less pitting and the surface is more active to a metal depositing solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.