Titanium dioxide pigments with improved gloss and/or durability
AssigneeMillennium Inorganic Chemicals, Inc.
InventorsBrian Tear, John Stratton, Robert Burniston
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Abstract
The present invention provides titanium dioxide pigments with improved gloss and/or durability. The titanium dioxide pigments are made by treating titanium dioxide with a plurality of metal salts under conditions suitable to form the titanium dioxide pigment having improved gloss and/or durability, wherein at least one metal salt is capable of providing a monovalent anion. Preferred pigments of the present invention are substantially-sulfate free.
Claims31
A method for preparing titanium dioxide pigment having improved gloss and/or durability comprising:
- a) treating titanium dioxide with a zirconia compound to form a first layer on the titanium dioxide consisting of sulfate-free zirconia;
- and b) treating the zirconia treated titanium dioxide with an alumina compound to form a second layer comprising sulfate-free alumina under conditions suitable to form the titanium dioxide pigment having improved gloss and/or durability, wherein the titanium dioxide pigment is substantially sulfate-free.
A method for preparing titanium dioxide pigment, having improved gloss and/or durability comprising:
- wet treating titanium dioxide with a sulfate-free alumina compound to form an alumina layer on the titanium dioxide, and wet treating the alumina treated titanium dioxide with a sulfate-free zirconia compound so as to form a sulfate-free zirconia layer thereby forming the titanium dioxide pigment having improved gloss and/or durability, wherein the titanium dioxide pigment is substantially sulfate-free.
A method for preparing titanium dioxide pigment having improved gloss and/or durability, comprising:
- wet treating an aqueous slurry of titanium dioxide with a sulfate-free alumina compound to form an alumina layer on the titanium dioxide, wet treating the alumina treated titanium dioxide with a sulfate-free zirconia compound capable of providing a monovalent anion to form a sulfate-free zirconia layer and wet treating the zirconia layer with a phosphate compound under conditions suitable to form the titanium dioxide pigment having improved gloss and/or durability, wherein the titanium dioxide pigment is substantially sulfate-free.
A titanium dioxide pigment having improved gloss and/or durability produced by a method comprising:
- a) wet treating titanium dioxide with an alumina compound to form a sulfate-free alumina layer on the titanium dioxide;
- b) wet treating the alumina treated titanium dioxide with a sulfate-free zirconia compound to form a sulfate-free zirconia layer;
- and c) wet treating the alumina and zirconia treated titanium dioxide with a sulfate-free phosphate compound under conditions suitable to form the titanium dioxide pigment having improved gloss and/or durability, wherein the titanium dioxide pigment is substantially sulfate-free.
A titanium dioxide pigment having improved gloss and/or durability produced by a method comprising:
- wet treating an aqueous slurry of titanium dioxide with a sulfate-free alumina compound, wet treating the alumina treated titanium dioxide with a sulfate-free zirconia compound capable of providing a monovalent anion to form a sulfate-free zirconia layer, and wet treating the alumina and zirconia treated titanium dioxide with a sulfate-free phosphate compound under conditions suitable to form the titanium dioxide pigment having improved gloss and/or durability, wherein the titanium dioxide pigment is substantially sulfate-free.
A substantially sulfate-free titanium dioxide pigment having improved gloss and/or durability comprising:
- titanium dioxide base, surface treated with an alumina compound, a zirconia compound on the alumina compound and a phosphate compound on the alumina compound.
A substantially sulfate-free titanium dioxide pigment according to claim the alumina compound comprises from about 1% to about 3.0% by weight Al2O3 based on the total weight of the titanium dioxide pigment.
A substantially sulfate-free titanium dioxide pigment having improved gloss and/or durability comprising:
- titanium dioxide base, surface treated with a compound consisting of zirconia, an alumina compound on the zirconia compound, and a phosphate compound on the zirconia compound.
Dependencies are inferred from the claim text.