High solid waterborne automotive base coat

As a new paper reveals, an excellent metallic effect can be realised with high solid aqueous automotive base coats.

Waterborne, aluminum effect pigment bearing coatings dry into automotive base coats (WBC) with viewing angle depending light reflectivity: the mirror like 2D pigments are oriented homogeneously not least due to the large shrinkage of shear thinning paint materials with low non volatile content (NVC). The present study describes higher NVC paint materials by making use of exfoliated α‑zirconium phosphate platelets (α-ZrP) and zirconium etidronate (Zr-HEDP) filaments with 7.5 and 0.3 wt%, respectively.

Highly angle dependent reflectivity

In both cases lyotropic liquid crystalline phases yield WBCs with highly angle dependent reflectivity. Analyses of the pigments’ distribution, inclination angles and their interphase with the matrix reveal an increased effective pigment volume fraction through an α-ZrP envelope and the high efficiency of ultra-long Zr-HEDP filaments on the pigments alignment.

The study has been published in Progress in Organic Coatings, Volume 160, November 2021.