Document b5LqYVQqmzON9JYbQEmxeZrvk
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by weight of the TiC>2/ of cerium cations and an associated 5 quantity of borate anions or polyfunctional organic acid
anions having a solubility in water of at least 10 grains per liter at 25C.
2. A pigment according to claim 1, wherein the
10 alumina or alumina-silica coating constitutes 0.5-10% of
the total weight of the Ti02 particles.
3. A pigment according to claim 2, wherein the alumina or alumina-silica coating constitutes 1-6% of the 15 total weight of the Ti02 particles.
4. A pigment according to claim 3, wherein the alumina or alumina-silica coating constitutes 2-4% of the total weight of the Ti02 particles. 20
5. A pigment according to any one of the preceding claims wherein the associated anions are borate ions.
6. A pigment according to claim 1, wherein the 25 associated anions are polyfunctional organic acid anions
having a solubility in water of at least 10 grams per liter at 25C.
7. A pigment according to any one of claims 1 to 4, 30 wherein the associated anions are citrate, succinate,
fumarate, adipate, tartrate or maleate ions.
8. A coating composition comprising a pigment according to any one of claims 1 to 7, a film-forming 35 material, and a liquid carrier.
N 30938
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CLAIMS 1. A pigment consisting essentially of rutle Ti02
particles bearing coatings of alumina or alumina-silica, the particle surfaces having associated therewith 0.05-2%, by weight of the Ti02 of cerium cations and an associated 5 quantity of borate anions or polyfunctional organic acid anions having a solubility in water of at least 10 grams per liter at 25c.
2. A pigment according to claim 1, wherein the
10 alumina or alumina-silica coating constitutes 0.5-10% of
the total weight of the Tio2 particles.
3. A pigment according to claim 2, wherein the alumina or alumina-silica coating constitutes 1-6% of the 15 total weight of the Tio2 particles.
4. A pigment according to claim 3, wherein the alumina or alumina-silica coating constitutes 2-4% of the total weight of the Ti02 particles. 20
5. A pigment according to any one of the preceding claims wherein the associated anions are borate ions.
6. A pigment according to claim 1, wherein the 25 associated anions are polyfunctional organic acid anions
having a solubility in water of at least 10 grams per liter at 25C.
7. A pigment according to any one of claims 1 to 4, 30 wherein the associated anions are citrate, succinate,
fumarate, adipate, tartrate or maleate ions.
8. A coating composition comprising a pigment according to any one of claims 1 to 7, a film-forming 35 material, and a liquid carrier.
DUP050449440