| 摘要 |
<p>The present invention relates to an iron oxide pigment containing precipitated crystalline titanium dioxide, obtainable by a process comprising the steps of adding an aqueous solution of at least one titanyl salt to an iron oxide pigment dispersion to form a reaction mixture; precipitating titanium dioxide on said iron oxide pigment by adding an alkali, wherein the titanium dioxide is precipitated at least partially in a crystalline form; and isolating the resulting titanium dioxide-containing iron oxide pigment from the reaction mixture,
wherein the iron oxide pigment dispersion and/or the reaction mixture is heated to a temperature of at least 50°C, and the pH of the reaction mixture during addition of the titanyl salt solution and/or the alkali to the iron oxide pigment dispersion is maintained below 6 and wherein the iron oxide pigment is selected from yellow iron oxide, red iron oxide and mixtures thereof, and its use as a photocatalytic material.</p> |
