Metal effect pigments, having a surface treatment comprising A) phosphoric acid (H3PO4), B) tetraethyl orthosilicate (TEOS) and C) at least one organic coupling agent to the metal effect pigments, exhibiting excellent humidity resistance performance without any influence on the chroma, luster and color of base metal effect pigments, a process for producing same and their use.

In some implementations, a pigment material includes an encapsulation material; and a flake structure disposed in the encapsulation material. The flake structure may include a core layer, wherein the core layer is a reflector layer, a set of metal barrier layers at least partially encapsulating the core layer, and a set of dielectric layers at least partially sandwiching the set of barrier layers.

There is disclosed a method including chemically converting a first material of a lamellar particle into a compound of the first material. The step of chemical conversion can be performed by a reactant, and the reactant can be in a form of at least one of a solid state, a liquid state, a vapor state, and a plasma state.