MERCK PATENTS LUSTROUS
BLACK INTERFERENCE PIGMENTS
Patent No. U.S. 7,303,622 B2
Merck Patent has received a
patent for lustrous black interference
pigments comprised of a mixture
of different substrates having a
coating of Fe3O4; a colorless coating
consisting of one or more layers each
having a refractive index of n<1.8; a
coating with an absorbent, highrefractive-
index material which contains
Fe3O4, a black sulfide, a black
oxynitride or a mixture thereof, and
which only covers part of the underlying
surface; and optionally an
outer protective layer.