Pyrogenically prepared SiO2 powder in the form of aggregated primary particles having a statistical thickness surface area of 10-500 m2/g, a thickening action based on the statistical thickness surface of 4-8 mPas.g/m. A process for preparing the pyrogenic SiO2 powder, which involves: introducing hydrolysable silicon compounds, a primary gas comprising oxygen, and a primary combustion gas into a mixing chamber to produce a mixture; igniting the mixture in a burner to produce a flame, which is burned into a reaction chamber to produce the pyrogenic SiO2 powder and gaseous substances; and separating the pyrogenic SiO2 powder from the gaseous substances, wherein a ratio of the amount of primary combustion gas introduced to a stoichiometric amount of primary combustion gas required, is referred to as primary gamma and has a value of less than 1, and wherein a ratio of the amount of primary gas comprising oxygen introduced to a stoichiometric amount of primary gas comprising oxygen required, is referred to as primary and has a value of greater than 1. A product comprising the pyrogenic silicon dioxide powder, lambda wherein the product is selected from the group consisting of a polyester film, a catalyst support, a polish for chemical mechanical polishing of metallic and oxidic surfaces, paint and an ink.
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