Pearlescent pigments coated with a metal oxide/hydroxide layer and an acrylic copolymer

A pearlescent pigment comprising a platelet-shaped substrate, a metal oxide coating comprising:

• a metal oxide layer having a refractive index of greater than 1.8;
• and
• a protective layer,
• wherein the protective layer comprises a metal oxide/hydroxide layer and optionally boroxide, applied to which is an organic aftercoat of an acrylic copolymer,
• wherein the metal oxide/hydroxide of the protective layer is selected from oxides/hydroxides of silicon (silicon oxide, silicon oxide hydrate), aluminium, zirconium, magnesium, calcium, iron(III), yttrium, cerium, zinc and combinations thereof, and
• wherein the acrylic copolymer comprises as copolymerized units the following monomers
• (A) an ethylenically unsaturated monomer containing at least one amino group;
• (B) an ethylenically unsaturated monomer containing no amino group;
• (C) optionally a hydroxy- or alkoxyalkyl(meth)acrylate of the formula
• CH2═CH(R1)—COO—C1H2t—OR2
• (D) a (poly)alkyleneglycolmono(meth)acrylate of the formula
• CH2═CH(R1)—COO—(CmH2mO)—OR2
• wherein R1 is hydrogen or methyl and R2 is hydrogen or C1-C6alkyl, t is an integer of 2, 3, 4, 5 or 6;
• and m is an integer of 2 or 3 and n is an intekger of 2 to 20.