Near neutral pH pickle on multi-metals
US10941496B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 17, 2019 |
| Grant date | Mar 9, 2021 |
| Priority date | — |
| Expiry date | Jul 23, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23G1/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A near neutral pH pickling composition for the removal of oxides from metallic surfaces, including heat treated steel. The pickling composition comprises a) a water-soluble organic or inorganic nitro compound, wherein a central N atom has an oxidation state of 3+; b) a polarizing agent for the nitro compound, wherein the polarizing agent comprises at least one of a phosphonate and a carboxylate; c) a pH buffer, and d) at least one metal complexing agent. The composition is preferably maintained at a pH between about 4.5 and about 7.5. The near neutral pH pickle composition can be used on various metallic surfaces as well as composite surfaces comprising metallic and non-metallic portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.