PROCESS FOR THE PRODUCTION OF A DARK-COLOR MULTI-LAYER COATING

摘要

A process for the production of a dark-color multi-layer coating, comprising the successive steps: (1) applying an NIR-opaque coating layer A' from a waterborne pigmented coating composition A to a substrate, (2) applying a coating layer B' from a waterborne pigmented coating composition B onto the substrate provided with coating layer A', (3) subjecting the coated substrate obtained in step (2) to a drying step, (4) applying a clear coat layer, and (5) curing the coating layers simultaneously; wherein both coating compositions A and B comprise aqueous microgel and sheet silicate, wherein the pigment content of coating composition A comprises < 90 wt.% of aluminum flake pigments and has such a composition that coating layer A' exhibits low NIR absorption, wherein the pigment content of coating composition B consists 50 to 100 wt.% of black pigment with low NIR absorption and 0 to 50 wt.% of further pigment.