| 摘要 |
<p>The invention relates to titanium dioxide sunscreen compositions containing 0.025 to 30 % by weight of phosphate anions. Phosphate anions, preferably in the form of salts, have been found to prevent or reduce the rate of discolouration of titanium dioxide-containing sunscreen compositions caused by light catalysed reduction of titanium (IV) to titanium (III). Discolouration caused by the presence of parahydroxybenzoic acid esters or para-aminobenzoic acids, esters or derivatives thereof in such compositions has also been found to be reduced by the incorporation of phosphate salt. Titanium dioxide particles having a mean primary particle size of less than 100 nm, each of the particles being substantially coated with phosphate anions are also described for use in sunscreen compositions.</p> |
