Method for forming multilayer coating film
US11634597B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 17, 2019 |
| Grant date | Apr 25, 2023 |
| Priority date | — |
| Expiry date | Apr 6, 2041 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K3/013
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method for forming a multilayer coating film which includes forming an uncured coating film by applying a first aqueous base coating composition, forming an uncured coating film by applying a second aqueous base coating composition, forming an uncured coating film by applying a clear coating composition, and simultaneously heat curing the obtained coating films. The first aqueous base coating composition contains a carbodiimide compound, the clear coating composition contains a hydroxyl group-containing acrylic resin (A) having a hydroxyl value of 120 to 160 mgKOH/g and an acid value of 5 to 10 mgKOH/g, a polyisocyanate compound (B), and a polycarbonate diol compound (C). The component (A) has a hydroxyl group-containing alkyl moiety having 3 or less carbon atoms, and the ratio of the numbers of moles of the isocyanate functional groups of the component (B) and the hydroxyl group functional groups of the component (A) is 1.15 to 1.35.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.