Leafing aluminium pigments
Leafing aluminium pigments exhibit a distinct tendency to float to the surface of the coating and to align parallel to the surface of the powder coating film.
Compared to coarse aluminium pigment particles, fine leafing aluminium pigments can move more easily towards the surface of the highly viscous melt of the powder coating film during the high-temperature curing process – resulting in more distinctive orientation and parallel alignment to the surface of the powder coating film.
For powder coatings therefore the special rule applies: the finer the leafing pigments, the more defined the chrome effect. Especially fine leafing aluminium pigments create powder coatings with particularly brilliant effects with extraordinary reflecting power and chrome-like optical appearance.
As a result of their distinct orientation close to the surface of the coating film, the leafing aluminium pigments are not completely embedded in the protective matrix of the powder coating and are therefore less well protected from mechanical or chemical influences than non-leafing aluminium pigments.
Therefore it is necessary to overcoat metallic powder coatings with a protective clear coat in order to protect the leafing metallic powder coating finish from unwanted corrosion processes and pigment abrasion.