Multi-layer effect pigment
View Patent ↗A multilayer effect pigment includes a transparent substrate, a layer of high refractive index material on the substrate, and alternating layers of low refractive index and high refractive index materials on the first layer, the total number of layers being an odd number of at least three, all adjacent layers differing in refractive index by at least about 0.2 and at least one of the layers having an optical thickness which is different from all of the other layers. The resulting multilayer effect pigment is not a quarter-wave stack. The present effect pigments may be used in cosmetic and industrial applications.
1. A multilayer effect pigment comprising:
a transparent substrate having a first layer of titanium dioxide thereon, said first layer having a thickness of 205±5 nm;
a second layer of silicon dioxide on said first layer, said second layer of silicon dioxide having a thickness of 80±5 nm; and
an outermost titanium dioxide layer placed on said second layer and having a thickness of 205±5 nm, said pigment being red, whereby the pigment is not a quarter-wave stack.