Frank J. Maile – SCHLENK 
Jiri Filip – SightTex
Realisation of gold-alloy shades using effect pigments
Various effect pigments like pearlescents and metal pigments made of gold or copper-zinc alloys have long been used to decorate surfaces in a wide variety of applications, although there is a difference in color formation. Colors in metallic elements and their alloys can be explained using band theory whereas the formation of (interference) colors in pearlescent pigments occurs through thin layers of higher refractive index deposited on semi-transparent substrates with platelet-like morphology[3]. Furthermore, compared to the physics of the gold-silver-copper alloys and their object surfaces, particle properties such as scattering at pigment edges and particle orientation must be taken into account when processing effect pigments in coatings, printing and plastics applications to achieve gold color shades on objects, since these significantly influence the final appearance [4].
