Abstract: A method of atomizing a polar liquid utilizes apparatus comprising a tube having an inlet for liquid and at least one aperture providing an outlet from the tube for the liquid and a field intensifying electrode disposed adjacent the aperture. The method comprises applying a potential difference between the polar liquid and the field intensifying electrode and feeding the liquid along the tube from the inlet to the aperture.In carrying out the method, the tube is supported at a position remote from the aperture and the potential difference, flow rate and tube stiffness are so selected relatively to each other that the tube can be electrostatically maintained in vibration or gyration to cause atomized liquid particles to be thrown from the tube at the aperture.

Abstract: Measurement of the color properties of wet paint, such as lightness by colorimetry or photospectrometry, is carried out on a sample volume contained in a vessel and while the sample volume is subjected to shearing forces and advantageously also turbulence. The shearing and turbulence are created by a rotating disc having a spiral rib configuration on one surface which faces a window through which the measurements are made by a spectrophotometer.

Abstract: Electrostatic spraying apparatus and process for spraying liquids which form a coalescent resistant surface in flight in a particular environment to produce a powder or granular material. The process involves delivering a liquid to a spraying site of an electrostatic spray head; making contact with the liquid via an electrically conducting or semiconducting liquid contacting surface; charging the liquid contacting surface to a high voltage of one polarity relative to a reference surface to intensify the electric field strength at the spraying site sufficiently that the liquid at the spraying site is drawn out preponderantly by electrostatic forces into at least one cone from which a corresponding ligament issues and breaks up into a spray of electrostatically charged droplets; providing the environment in a space sufficient that droplets from the spray head form, in flight, particles having a substantially coalescent resistant surface; and collecting the particles so formed.