Patent ID: 8215822

Claim:
An ultrasonic mixing system for preparing an antimicrobial formulation, the mixing system comprising: a treatment chamber comprising: an elongate housing having longitudinally opposite ends and an interior space, the housing being generally closed at least one longitudinal end and having a first inlet port for receiving a formulation into the interior space of the housing; a second inlet port for receiving an antimicrobial agent; and at least one outlet port through which an antimicrobial formulation is exhausted from the housing following ultrasonic mixing of the formulation and antimicrobial agent to form the antimicrobial formulation, the outlet port being spaced longitudinally from the first and second inlet ports such that the formulation and antimicrobial agent flow longitudinally within the interior space of the housing from the first and second inlet ports to the outlet port; and an elongate ultrasonic waveguide assembly extending longitudinally within the interior space of the housing and being operable at a predetermined ultrasonic frequency to ultrasonically energize and mix the formulation and antimicrobial agents flowing within the housing, the waveguide assembly comprising an elongate ultrasonic horn disposed at least in part intermediate the first and second inlet ports and the outlet port of the housing and having an outer surface located for contact with the formulation and antimicrobial agents flowing within the housing from the first and second inlet ports to the outlet port, and a plurality of discrete agitating members in contact with and extending transversely outward from the outer surface of the horn intermediate the first and second inlet ports and the outlet port in longitudinally spaced relationship with each other, the agitating members and the horn being constructed and arranged for dynamic motion of the agitating members relative to the horn upon ultrasonic vibration of the horn at the predetermined frequency and to operate in an ultrasonic cavitation mode of the agitating members corresponding to the predetermined frequency and the formulation and antimicrobial agents being mixed in the chamber, wherein the ratio of the transverse length of at least one of the agitating members to the thickness of the agitating member is in the range of about 2:1 to about 6:1.