초록 ▼

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

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.

대표청구항 ▼

Apparatus for manufacturing powders or granular materials from liquids capable of quickly forming a coalescent resistant surface in a particular environment, comprising: an electrostatic spray head having a spraying site, an electrically conducting or semiconducting liquid contacting surface and mea

Apparatus for manufacturing powders or granular materials from liquids capable of quickly forming a coalescent resistant surface in a particular environment, comprising: an electrostatic spray head having a spraying site, an electrically conducting or semiconducting liquid contacting surface and means for delivering the said liquid to the spraying site a reference surface external to the sprayhead; high voltage supply means for charging the liquid contacting surface to said high voltage of one polarity relative to a reference surface, said voltage being sufficiently high and in combination the spraying site being sufficiently sharp, as to intensify the electric field strength at the spraying site sufficiently when covered, in use, by the liquid to be sprayed, that the liquid at the spraying site is drawn out preponderantly by electrostatic forces into a spray of at least one cone from which a corresponding ligament issues and breaks up into electrostatically charged droplets; means for providing said environment in a space sufficient that droplets from the spray head form, in flight, particles having a substantially coalescent resistant surface; and means for collecting the particles so formed. A process for manufacturing powders or granular materials from liquids capable of forming a coalescent resistant surface in a particular environment, comprising: delivering said liquid to a spraying site of an electrostatic spray head; making electrical contact with said 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 said 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.