Multilayered interference pigments

US6132873A · kind A · utility

Assignee

• Merck Patent GmbH · DE

Inventors

• Johann Dietz · Dietzenbach, DE
• Manfred Parusel · Munster, DE
• Matthias Schilling · Alsbach, DE
• Klaus Ambrosius · Frankfurt, DE

Key dates

• Filing date: Apr 17, 1998
• Grant date: Oct 17, 2000
• Expiry date: Apr 17, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2993
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Multilayer interference pigments consisting of a transparent carrier material coated with alternating layers of metal oxides of low and high refractive index, the layers of the metal oxides of low refractive index being optically inactive. The thickness of the metal oxide layers of high refractive index is an integral multiple of the optical thickness which is necessary for the desired interference color. The layer thickness of metal oxide layers of low refractive index is from 1 to 20 nm.