Patent ID: 8568628

Claim:
A method of preparing a toner, comprising: periodically dripping and discharging droplets of a toner constituent liquid comprising a resin and a colorant with a dripper, the dripper comprising a thin film being a metallic film having a thickness of from 5 to 500 μm and having a planar shape, and comprising plural nozzles configured to discharge the droplets in a liquid discharge direction, and an electromechanical converter configured to oscillate the thin film and including an oscillator disposed to oscillate the plural nozzles, wherein one oscillator causes a plurality of the nozzles discharge a liquid; and solidifying the droplets to form toner particles, wherein each particular nozzle of the plural nozzles has an aperture in a liquid contact surface of the thin film, the liquid contact surface being in contact with the toner constituent liquid, and an aperture in a liquid discharge surface of the thin film from which a droplet is discharged, the aperture in the liquid discharge surface of the thin film having a circular or an ellipsoidal cross-sectional shape and a cross-sectional area smaller than a cross-sectional area of the aperture contacting the toner constituent liquid, the nozzle is tapered from the aperture in the liquid contact surface of the thin film toward the aperture in the liquid discharge surface of the thin film, and the nozzle gradually narrows from the liquid contact surface to the liquid discharge surface such that a cross-section of the nozzle along the liquid discharge direction has curved sides, and wherein the plural nozzles through which the droplets are discharged are disposed on the thin film to form one or more offset arrays, and wherein a pitch between the nozzles, which are formed by nickel electroforming and are disposed on the thin film to form the offset arrays, has a length not less than 3 times as long as a diameter of the aperture discharging the droplet.