Cocoon-shaped rutile-type titanium dioxide, as well as cosmetics and external additives for toner comprising the same

摘要

The present invention provides products comprising rutile-type titanium dioxide of a specific shape, i.e., cosmetics which have high UV blocking ability, provide a good feel upon use without leaving squeakiness or graininess on the skin, and also give a natural bare skin appearance without causing white masking, due to adequate tinting strength and covering power, as well as external additives for toner which are excellent in prevention of filming on a photosensitive member and inhibition of aggregation between toner particles. The present invention is directed to rutile-type titanium dioxide having a specific surface area of 120 to 180 m 2 /g in the form of oriented and aggregated particles, in which the major axial planes of rod-shaped particles each having a minor axial diameter of 3 to 10 nm are oriented and aggregated in the minor axial direction, wherein the oriented and aggregated particles have an apparent mean major axial length of 80 to 300 nm, an apparent mean minor axial length of 30 to 150 nm, and an apparent mean axial ratio (apparent mean major axial length/apparent mean minor axial length) of 1.1 to 4, and wherein both major axial ends of the oriented and aggregated particles are round- or elliptical-shaped, as well as cosmetics comprising this titanium dioxide, and external additives for toner comprising this titanium dioxide which is hydrophobically treated.