Material, Construction and Processes

The dominant class of lustre pigments is based upon oxide coatings of mica platelets, but newer materials have appeared e.g. silica and alumina flakes from Merck, with better performance characteristics than traditional mica. There has also been developments in the technology for the coating of reflective metal platelets, e.g. aluminium, with oxides using chemical vapour deposition that has led to exciting new products.  

By using layers of FCjOj brilliant, intense coloms can be obtained from layers only 50-250 mn in thickness. The FCjOj-mica pigments form absorption and interference coloms simultaneously, the observed coloms again being dependent on the layer thickness. 

Note both sides of piates are covered, not on one side as shown schematicaliy here 

Silica and alumina based pigments. These new substrate materials, SiO and Al Oj which were developed by Merck, are absolntely flat and therefore allow the production of very intense interference colonrs that can be coupled with a variety of goniochromic properties.  

FCjOj/SiOj pigment in conjunction with a mixture of Phthalocyanine Blue (Cl Pigment Blue 15.1) and Phthalocyanine Green (Cl Pigment Green 36) and Carbon Black. 

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