Nitrogen doped carbon-coated effect pigments and their manufacture
US6436538B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 13, 1999 |
| Grant date | Aug 20, 2002 |
| Priority date | — |
| Expiry date | Aug 13, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2998
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention relates to a collection of composite plateletlike particles comprising a core and at least one coating layer consisting essentially of a compound having from 60 to 95% by weight of carbon and from 5 to 25% by weight of nitrogen, the balance to 100% being selected from elements of the group consisting of hydrogen, oxygen and sulfur.The invention also relates to processes for the manufacture thereof, to polymer compositions containing it, and to the use thereof as effect pigments.Preferably, the process for preparing the instant collection of particles comprises the steps of(a) suspending plateletlike particles in a liquid;(b) optionally adding a surface modifier, a polymerisation catalyst or both;(c) before or after step (b), adding one or more polymers containing nitrogen and carbon atoms, or one or more monomers which are capable to polymerize to said polymer;(d) effecting a polymeric coating layer to be formed on the surface of said plateletlike particles from the polymers or monomers added at step (c);(e) isolating said plateletlike particles having said polymeric coating layer from the suspension; and(f) heating said plateletlike particles having said polymeric co…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.