Composite paint film
US5075165A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 1990 |
| Grant date | Dec 24, 1991 |
| Priority date | — |
| Expiry date | May 11, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31699
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A composite paint film formed on a steel sheet of an automotive vehicle body. The composite paint film comprises an electrodeposition paint film (I) coated on the steel sheet, and an intermediate coat paint film (II) coated on the first paint film. The electrodeposition paint film is formed of an epoxy-based cationic electrodeposition paint composition and has a minimum melt viscosity not less than 0.2 during hardening. The epoxy-based cationic electrodeposition paint composition includes an amine-added epoxy resin (1) of the type which may be hardened with a blocked isocyanate, a colloidal silica-containing gelled particulate (2), and an alkyltin ester compound of a liquid aliphatic carboxylic acid. The above-mentioned colloidal silica-containing gelled particulate is formed by dispersing a mixture of an acrylic copolymer having a hydrolizable alkoxysilane group and a cationic group and a cationic acidic colloidal silica in water to carry out a cross-linking reaction in particles of the colloidal silica. The second paint film (II) has a hardening starting time ranging from 15 to 20 minutes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.