Method of performing pre-paint treatment of automobile body and automobile body
US11702757B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Mar 23, 2022 |
| Grant date | Jul 18, 2023 |
| Priority date | — |
| Expiry date | Mar 23, 2042 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25D13/20
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Provided is a method of performing pre-paint treatment of an automobile body including a high-tensile steel sheet, in which desirable corrosion resistance can be obtained after painting. A method of performing pre-paint treatment of an automobile body, the method including performing an alkaline degreasing step, a first water-washing step, a chemical conversion treatment step, a second water-washing step, and a cationic electrodeposition painting step, in this order, wherein the chemical conversion treatment step is performed using an chemical conversion treatment agent including zirconium (A), free fluorine ions (B), an allylamine-diallylamine copolymer (C), aluminum ions (D), nitrate ions (E) each at a predetermined concentration; the allylamine-diallylamine copolymer (C) forms an acid addition salt having an anionic counter ion, and the pKa of an acid thereof falls within the range of −3.7 to 4.8; and the content percentage of diallylamine is 80 mol % or more and 98 mol % or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.