Vesiculated polymer granules containing TiO.sub.2

A vesiculated pigment granule having a diameter of 1-50 microns, the granule comprising

• (a) 1-60%, by weight, of TiO.sub.2 particles in a matrix of an unsaturated polyester resin cross-linked with a polymerizable unsaturated monomer,
• (b) 5-95%, by volume, of voids, and
• (c) 0.5-4.0%, by weight of the TiO.sub.2, of a phosphate ester represented by the structure
• (R--O--(CH.sub.2).sub.y ].sub.n O).sub.x PO.sub.4-x Z.sub.3-x
• where
• R is an aliphatic hydrocarbon radical of 4-16 carbon atoms, an octylphenol radical or a nonylphenyl radical,
• n is 4-12,
• x is 1 or 2,
• y is 2 or 3, and
• z is H, Na or K.