The present invention relates to a radar-compatible coating comprising metal-effect pigments on a substrate, to a process for the production of such a coating, and to the use of a substrate coated in this manner, in particular in vehicle construction.

To provide a coating film having higher luminance. A coating composition including a coating-film-forming resin and a pigment, wherein: the pigment includes a scaly vapor-deposited metal pigment; and a cured coating film of the coating composition has a sparkle intensity (Si) at an angle of incidence of 45° of 20 or higher, a sparkle area (Sa value) of 10 or higher, and a granularity value (G value) that exceeds 10.

A composite pigment containing a substrate particle and a pigment layer arranged on a surface of the substrate particle, wherein the pigment layer contains a pigment, a resin and a metal oxide, and the metal oxide contains at least one selected from the group consisting of a silicon oxide, a polysiloxane, and composites thereof.

The invention provides a method for applying a new form of protective coating to substrates such as pigments, and also the coated substrates obtainable by this method. The coating are characterized by the fact that they impart good chemical resistivity to the substrate whilst also preserving its optical properties.

A process for producing pigments having a defined size and shape and also pigments produced by this process. The process has the steps: a) production of a three-dimensional surface structure on a substrate, with surface regions which are in each case partly bounded by a plurality of three-dimensional structural elements and are arranged in gaps being formed; b) application of a pigment material layer to the surface structure; c) detachment of the pigment material layer from the surface structure and production of pigments.

An aqueous coloring composition contains a metal pigment, water, and organic solvents. The metal pigment is metal particles having a surface treated with at least one compound represented by formula (1) or (2), and the organic solvents include an organic solvent (A), having a water solubility of 1000 g/L or more at 20° C., and an organic solvent (B), having a water solubility of 100 g/L or less at 20° C.

(R.sup.1—)P(O)(OH).sub.2  (1)

(R.sup.2—O—).sub.aP(O)(OH).sub.3-a  (2)

(In the formulae, R.sup.1 and R.sup.2 independently represent a hydrocarbon group having 12 or more carbon atoms, optionally substituted with one or more substituents, and a represents 1 or 2.)

An aqueous coloring composition contains a metal pigment, water, and organic solvents. The metal pigment is metal particles having a surface treated with at least one compound represented by formula (1) or (2), and the organic solvents include an organic solvent (A), having a water solubility of 1000 g/L or more at 20° C., and an organic solvent (B), having a water solubility of 100 g/L or less at 20° C.

(R.sup.1—)P(O)(OH).sub.2  (1)

(R.sup.2—O—).sub.aP(O)(OH).sub.3-a  (2)

(In the formulae, R.sup.1 and R.sup.2 independently represent a hydrocarbon group having 12 or more carbon atoms, optionally substituted with one or more substituents, and a represents 1 or 2.)

A resin coated inorganic or metallic pigment includes inorganic or metallic particles (A) and an acrylic copolymer (B) formed on the inorganic or metallic particles (A) by subjecting a radically polymerizable unsaturated carboxylic acid or radically polymerizable phosphate monomer (B1) and a monomer (B2) containing 3 to 6 (meth)acryloyloxy groups per molecule to radical polymerization reaction using a polymerization initiator (C) containing a nitrile group, wherein the inorganic or metallic particles (A) are coated with a coating resin including the acrylic copolymer (B), and the acrylic copolymer (B) has at a tail thereof a structure which is derived from the polymerization initiator (C) and which is represented by the following general formula (1): ##STR00001##
wherein R.sup.1 represents a methyl group, and R.sup.2 represents an alkyl group having 2 to 5 carbon atoms, or the like.

An aluminum flake pigment is an aluminum flake pigment including aluminum flakes, wherein the aluminum flakes include small-size aluminum flakes each having a particle size of less than or equal to 1 μm, and in a microscope image when the aluminum flakes are observed using a scanning electron microscope, a ratio of the number of the small-size aluminum flakes is less than or equal to 35% with respect to the number of a whole of the aluminum flakes.

An aluminum flake pigment is an aluminum flake pigment including aluminum flakes, wherein the aluminum flakes include small-size aluminum flakes each having a particle size of less than or equal to 1 μm, and in a microscope image when the aluminum flakes are observed using a scanning electron microscope, a ratio of the number of the small-size aluminum flakes is less than or equal to 35% with respect to the number of a whole of the aluminum flakes.