Metal pretreatment composition containing zirconium, copper, zinc and nitrate and related coatings on metal substrates
US11131027B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 24, 2018 |
| Grant date | Sep 28, 2021 |
| Priority date | — |
| Expiry date | Jul 23, 2039 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12139
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A pretreatment composition for metal that provides enhanced corrosion resistance, enhanced paint adhesion and reduced chip damage to a wide variety of metal substrates. The pretreatment is also cleaner because it is based on zirconium rather than zinc phosphates. The pretreatment coating composition in use preferably comprises 50 to 300 parts per million (ppm) zirconium, 0 to 100 ppm of SiO2, 150-2000 ppm of total fluorine and 10-100 ppm of free fluorine, 150 to 10000 ppm of zinc and 10 to 10000 ppm of an oxidizing agent and has a pH of 3.0 to 5.0, preferably about 4.0. The coating composition can optionally include 0 to 50 ppm of copper. The suitable oxidizing agents can be selected from a large group.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.