Abstract: A container for the electrostatic spraying of liquids, especially pesticides, having an integral conductive spray nozzle formed from two concentric tubes in which axial ribs and grooves between the tubes provide a liquid pathway to the nozzle mouth. Air is bled into the container in use through an extended pathway provided by a helical thread on the surface of a bung in the upper end of the inner tube.

Abstract: A liquid container adapted to form part of an electrostatic spraying apparatus and having attached to it a high voltage generator to supply the voltage required for the electrostatic spraying. The container and apparatus also include the electrical contacts necessary to connect the generator to an electrical power supply and to the electrostatic spraying apparatus.

Abstract: A holder for receiving a container which contains a liquid suitable for electrostatic spraying and which has a spray orifice comprises a body having a high voltage generator; a power source therefor; a field-intensifying electrode; electrical connections for connecting the electrode to an output terminal of the high voltage generator and for connecting the output terminal and the field-intensifying electrode to earth; a mounting device complementary to a mounting device on the container for locating the container on the holder with the spray orifice adjacent the electrode, the complementary mounting device having an electrical contact complementary to one on the container; and electrical connections for connecting the contact to the other output terminal of the high voltage generator.

Abstract: Spraying apparatus for spraying liquid pesticides on to crops growing in the ground includes a plurality of electrostatic spraying devices mounted on a boom which can be mounted on a powered vehicle such as a tractor or an aircraft. Each spraying device includes a spray-head having an at least electrically semi-conducting surface charged to a potential of the order of 1-20 kilovolts, a field intensifying electrode mounted adjacent the spray-head surface and being so sited relative to the spray-head surface that the electrostatic field thereat causes pesticide liquid delivered thereto to atomize without substantial corona discharge to form electrically charged particles.

Abstract: A system for the electrostatic spraying of liquids, particularly suitable for the application of pesticides at low volume. A sealable demountable container and support are provided, liquid being supplied from the container for atomization to an electrically conductive nozzle charged from one output terminal of a high voltage generator. Another output terminal of the high voltage generator connects to a field-intensifying electrode adjacent the nozzle, the electric circuit in the holder being completed by connections in the container. The nozzle and electrical power source preferably are carried on the container.

Abstract: A device to use as an agricultural sprayer, comprising a rotatable conductive sprayhead in the form of a disc or cup, means for supplying spray liquid from a reservoir to an inner surface of the sprayhead, an electric motor for rotating the sprayhead about its axis at a rate of 1000 to 8000 rpm, a circular induction electrode disposed adjacent the sprayhead rim, a high voltage generator for charging the electrode to a pontential in the range 1 to 3 Kilovolts, and means for earthing the sprayhead.

Abstract: An electrostatic pump in an electrostatic sprayer is disclosed which comprises an ion injection electrode means disposed in a liquid conduit for conveying liquid to a sprayhead, downstream of the ion injection electrode is an ion discharge electrode means comprising an earthed ring, a potential difference is provided between the electrodes to provide hydrostatic pressure for conveying liquid in a conduit to the sprayhead.

Abstract: Electrostatic spraying of liquid compositions is carried out by supplying the liquid to a spray orifice, preferably of capillary dimensions, having a charged surface which is electrically conducting or semi-conducting and which is adjacent a field intensifying electrode, the arrangement being such that the liquid is drawn out primarily by electrostatic forces, atomized into electrically charged particles without substantial corona discharge and projected past the field intensifying electrode. The spraying process and apparatus has particular utility in the spraying of liquid pesticide compositions at ultra-low volume, in that the droplets are of uniform size and are electrostatically attracted to the plants so as to wrap around the leaves of the planets and coat both the upper and lower surfaces of the leaves.

Abstract: An electrostatically sprayable insecticidal formulation comprising a solution of from 0.5 to 50% of permethrin or like compound in an organic solvent medium, the medium being formulated so that the formulation has a resistivity at 20.degree. C. in the range 1.times.10.sup.6 to 1.times.10.sup.10 ohm centimeter and a viscosity at 20.degree. C. of 5 to 50 centistokes.

Abstract: A liquid container is provided adapted to form a part of apparatus for electrostatic spraying of liquids, such as pesticides. The container includes a body having an orifice for delivering liquid to a spray nozzle, and a closure for sealing the orifice prior to location of the container on the apparatus. The orifice is opened only when the container is mounted on the apparatus, and the orifice is reclosed when removed from the apparatus. An electrostatic valve may comprise the closure.

Abstract: A system for the electrostatic spraying of liquids, particularly suitable for the application of pesticides at low volume. A sealable demountable container and support are provided, liquid being supplied from the container for atomization to an electrically conductive nozzle charged from one output terminal of a high voltage generator. Another output terminal of the high voltage generator connects to a field-intensifying electrode adjacent the nozzle, the electric circuit in the holder being completed by connections in the container. The nozzle and electrical power source preferably are carried on the container.

Abstract: A container for use in the electrostatic spraying of liquids, and a holder suitable for receiving the container. The container has a spray nozzle with at least part of the surface of the spray nozzle being electrically conductive. An electrode is disposed about the nozzle and insulated therefrom. A mounting structure is provided on the holder for locating the container, and separate electrical connections from the nozzle and the electrode to separate contacts on the mounting structure are so placed that when the container is located on the holder by the mounting structure each contact can make connection with one output terminal of a high voltage generator carried by the holder.