Carbon coated high luster materials
A platy pigment substrate having a carbon-containing coating thereon is provided wherein the coating comprises a pyrolyzed carbon-containing ionic species. The products of the present invention may be used in any application where pearlescent pigments have been used heretofore including but not limited to automotive and industrial paint applications.
1. A pigment comprising an effect pigment substrate having a pyrolyzed carbon-containing organic coating thereon, said organic coating comprising at least one carbon-containing ionic polymer species and said pyrolyzed carbon-containing organic coating contains below 4 weight percent nitrogen.
2. The pigment of claim 1 wherein said effect pigment substrate is a platy substrate.
3. The pigment of claim 1 wherein said carbon coating is less than about 5% of the total weight of the pigment.
4. The pigment of claim 1 wherein the effect pigment substrate is titanium dioxide-coated mica.
5. The pigment of claim 1 wherein the effect pigment substrate is iron oxide-coated mica.
6. The pigment of claim 1 wherein said carbon-containing ionic polymer species is comprised of a cationic or anionic polymer.
7. The pigment of claim 6 wherein prior to said pyrolysis, said organic coating is comprised of alternating layers of cationic and anionic polymers.
8. The pigment of claim 6 wherein said cationic polymer contains nitrogen.
9. The pigment of claim 6 wherein said anionic polymer contains carboxylic acid or carboxylate groups.
10. The pigment of claim 6 wherein said anionic polymer contains sulfur.
11. The pigment of claim 4 further containing cerium oxide.
12. The pigment of claim 4 further containing a metal oxide and silane coupling agent applied onto said carbon coating so as to improve weatherability of the pigment.
13. The pigment of claim 1 wherein said effect pigment substrate is mica, bismuth oxychloride, glass, platy iron oxide, platy aluminum oxide, platy silicon dioxide, or metal oxide-coated derivatives thereof.
14. The pigment of claim 13 further containing cerium oxide.
15. The pigment of claim 1 containing divalent iron, trivalent iron, or mixtures thereof.
16. The pigment of claim 15 wherein said effect pigment substrate comprises Fe 2 O 3 and TiO 2 coatings on mica.
17. The pigment of claim 1 wherein said substrate is coated with at least one alternating sequence of polydiallyldimethyl animonium chloride and poly (sodium 4-styrene sulfonate).