Titanium dioxide, usage

Divestment of the nitrogen fertiliser and titanium dioxide businesses, and expansion of the environmental business announced as a result of changes to the business strategy, should result in a substantial reduction in energy usage and releases to air and water in 2000. 

Paints and pigments 400 000 A declining usage. Titanium dioxide is now increasingly made by the chloride and not the sulphate route... 

Filler usage parallels standard PVC formulating, except that the use of hydrous hllers (ATH, magnesium hydroxide, hydrous silica, zeolite) can lead to viscosity instability, particularly with carboxylated grades. The latter are sufficiently sensitive that silica or ATH surface treatments of titanium dioxide (a beneht everywhere else) can destabilize solution viscosity. In some cases, viscosity build can be reversed with low levels (0.25-1 percent) of citric acid or lauryl acid orthophosphate. 

The compounds used are semirigid and, in some cases, ABS blends. In the case of a straight PVC compound, 30-40 phr of a low-volatility phthalate or trimellitate plasticizer is used. From 15 to 20 phr calcium carbonate is supplemented with 1 phr titanium dioxide, 1-2 phr antimony trioxide for improved flame resistance, 2-3 phr ESO, colorants as required, and about 0.1 phr (or less) stearic acid. The stabilizers used are barium/zinc or calcium/zinc powders supplemented with mineral acid absorbers and also a source of perchlorate anion. The latter is active in scavenging amine catalysts migrating fiom the PUR layer, which rapidly discolor PVC. If need be, minor amounts of dispersion resin or of acryhc processing aid can be added to compounds such as the above to improve flowability. Although principally used in the United States for instrument panels, European and Japanese usage in arm and head rests has also been reported. 

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