relative to the solid component the titania nanoparticles manufactured according to the present invention described above have a monodisperse spherical form with nearly identical size the surfaces of these monodisperse spherical particles is coated with a hydrophobic substance thereby enabling effective use as a external toner additive the size of titania nanoparticles of the present invention thus manufactured can be adjusted at will when used as an external toner additive the size should be from 30 to 200 nm as needed the spheres may have a median diameter of 30 nm 50 nm 100 nm 150 nm or 200 nm in addition the titania nanoparticles of the present invention show a contact angle of 100 u00b0 or greater with respect to water in the case of the contact angle with water the measured limit value was 170 u00b0 but in theory it could be up to 180 u00b0 if said contact angle with water is less than 100 u00b0 hydrophobicity will suffer and when used as an external toner additive the print quality of the toner may suffer due to either the adsorption of airborne moisture or the formation of aggregates in addition it is preferable that the specific surface area of the titania nanoparticles be between 20 and 100 m2 g if said specific surface area is less than 20 m2 g the aggregation of particles may be severe because this makes it difficult for the final coating of the toner with external additive to be uniform it may cause a problematic deterioration in toner print quality if it exceeds 100 m2 g this indicates that the initial particles will be very small which also makes the hydrophobic coating of individual.