Silicon dioxide, fumed

Pyrogenically produced silica powder having a BET surface area of 30 to 90 m It is prepared by mixing at least one vaporous silicon compound, a free-oxygen containing gas and a fuel gas in a closed burner and burns in the flame tube of the burner below in a flame, separating the resulting solid from the gas mixture and optionally purified, wherein the oxygen content of the free oxygen-containing gas is adjusted so that the lambda value is greater than or equal to 1, and the gamma-value is between 1.2 and 1.8. It can be used in toner applications.