Localized liquid additive applicator system for continuous cylindrical

Abstract

A continuous rod of a product such as a cigarette filter material is coated with a treating liquid by being passed axially through a cylindrical applicator zone comprising a permeable cylindrical wall, the cylindrical wall being concentrically enclosed within a reservoir and manifold zone connected to a source of liquid. The feed supply for the liquid additive can be pressurized and/or heated, so that application of the additive can be in either liquid or vapor form. The process and apparatus of this invention may be used alone or in conjunction with prior art homogeneous applicators and processes. When used to apply a plasticizer to a rod of continuous filament tow, e.g. for use in producing cigarette filters, annular regions of varying concentrations of the plasticizer are produced in the rod. A relatively dense region of plasticized fiber can be produced on the outside of the filter. Filter rods having wrapping paper uniformly adhered about the periphery of the rod can be produced. By installing the applicator apparatus between the transport jet and the garniture tongue of a typical cigarette filter rod making machine, the invention permits the production of satisfactory paper wrapped filter rods having unique depression on loading characteristics.