Dyed lustrous pigments
AssigneeMerck Patent GmbH
InventorsHorst Bernhard, Kurt Marquard
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Abstract
Lustrous pigments having a wide range of colors and especially suitable for the cosmetics industry are produced by forming an aluminum lake on a micaceous pigment coated with aluminum hydroxide.
Claims21
In a colored lustrous pigment composition comprising translucent micaceous flakes coated with a dyestuff, the improvement wherein said dyestuff is an aluminum lake fixed onto the surface of the micaceous pigment by a smooth and uniform intermediate coating of aluminum hydroxide, the aluminum of said aluminum hydroxide being a chemically bound portion of said aluminum lake, the pigment composition being substantially devoid of agglomerated flakes and being substantially color fast.
A pigment composition comprising a micaceous pigment coated with a chelation compound of aluminum, said chelation compound having a solubility at 22.degree. C. of less than 1 g. per liter of water and being capable of being reacted with a diazotized amine to form an azo dyestuff, wherein interposed between said chelation compound and said micaceous pigment is a smooth and uniform coating of aluminum hydroxide, the aluminum of said hydroxide being a part of said chelation compound.
Dependencies are inferred from the claim text.