Aminoplast-based crosslinkers and powder coating compositions containing such crosslinkers
US6500545B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 21, 2000 |
| Grant date | Dec 31, 2002 |
| Priority date | — |
| Expiry date | Sep 21, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31942
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention provides a crosslinking agent having reactive benzoxazine groups which is the ungelled reaction product of (a) at least one mono-hydroxy aromatic compound and (b) at least one aminotriazine compound having one or less non-alkylated NH group present in a molar ratio of reactant (a) to reactant (b) ranging from 1.0 to 3.0: 1.0, provided that where reactant (a) is a single ring monohydroxy aromatic compound, the molar ratio of reactant (a) to reactant (b) ranges from 1.0 to 1.8:1.0 and from 2.2 to 3.0:1.0. The crosslinking agent is essentially free of hydroxyl functionality and has a glass transition temperature of at least 25° C. The present invention is further directed to a method for preparing the above-described crosslinking agent. Also provided is a curable powder coating composition comprising a solid particulate, film-forming mixture of (A) a polymer having functional groups reactive with aminotriazine and/or benzoxazine groups, the polymer having a glass transition temperature of at least 30° C.; and (B) the previously described crosslinking agent. Multilayer composite coating compositions are also provided including a base coat deposited from a …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.