Thermosetting coatings containing carbodiimides
US5104928A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1990 |
| Grant date | Apr 14, 1992 |
| Priority date | — |
| Expiry date | Jan 12, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09D175/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Thermosetting coating compositions are based on a binder comprising carboxyl functional polyurethane, acrylic copolymer, and if desired a carbodiimide crosslinker. The binder is produced by synthesizing an isocyanate terminated, carboxyl functional urethane prepolymer in the absence of water and organic solvent but in the presence of ethylenic monomers. The organic phase urethane prepolymer dispersed in ethylenic monomers is inverted into water whereupon the urethane prepolymer is extended by reaction with a primary or secondary polyamine such as diamine to produce a high molecular weight polyurethane-urea. Thereafter, the ethylenic monomers are copolymerized to form an aqueous dispersed polyurethane-urea and acrylic copolymer mixture. The resulting polymeric binder is useful in protective surface coatings applied to plastic substrates. A carbodiimide can be added to provide thermosetting crosslinking with the carboxyl functional polyurethane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.