Abstract: A sprayable aqueous coating composition for motor vehicles comprising an aqueous dispersion of addition polymer microparticles having a crosslinked core and a non-crosslinked stabilising mantle containing acid groups, characterised in that the crosslinked core comprises: i) a crosslinked inner core of an addition polymer and ii) a crosslinked outer core of addition polymer which is made from at least 10% by weight of monomers having a solubility in water of less than 0.1% by weight ratio of the inner core to the outer core being in the range 10:90 to 90:10.

Abstract: The invention provides an aqueous coating composition which comprises a film forming polymer and a particulate metallic pigment characterized in that the composition contains as corrosion inhibition agent for the pigment a phosphatic material containing at least one acidic hydroxyl group or a salt thereof linked to a phosphorus atom and which has been obtained by the co-reaction of (i) an addition polymer carrying a functional hydroxyl group, (ii) a monohydric alcohol or phenol and (iii) a compound containing in the molecule the grouping: ##STR1## or a compound equivalent in structure to such a grouping.

Abstract: The tendency of metallic pigments, especially of aluminum flake pigments, to react with the aqueous medium of a water-born paint composition with the generation of gaseous material is prevented or reduced by incorporating in the composition an agent containing in the molecule at least one P--OH group, or a salt derivative thereof, which is obtained by reacting a compound containing the grouping --O--PO(OH.sub.2) with one or more epoxide group-containing compounds at least one of which also contains at least one aromatic or alicyclic group.