DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT This invention is directed to a process for measuring the thickness of a layer of powder upon a workpiece.
The process comprises the steps of depositing a layer of powder on the surface of a workpiece and simultaneously on the surface of an adjacent wire, directing the powder coated wire past a sensor capable of measuring the diameter of the powder coated wire, and comparing the diameter of the powder coated wire to the diameter of the uncoated wire.
Suitable powders for use according to the present invention include, but are not necessarily limited to, particles of paint, phenolic resin, alkyd resin, urea-formaldehyde resin, rubber, vinyl polymer, polyurethane resin, silicone resin, latex, epoxy resin, styrenic resin, and the like, as well as blends and copolymers thereof.
Generally, the particles range in size from about 15 micrometers to about 250 micrometers.
These powders may be sprayed from conventional powder spray or electrostatic spray devices which are well-known in the art.
The powder is sprayed onto the surface of a workpiece that is to receive a monolithic coating of the sprayed, cured material.
The powder may simply be mechanically sprayed onto the surface of the workpiece, or the spraying process may be assisted by causing the powder to be electrostatically attracted to the surface of the workpiece.
As will be readily apparent to those ordinarily skilled in the art, other conventional methods may also be used to deposit the powder onto the surface of the workpiece, such as for example by sprinkling, dipping, or fluid bed coating.
As the powder is deposited onto the surface of the workpiece, it is simultaneously deposited onto the surface of an adjacent wire.
Conventional wire materials may be used including, by way of example but not limitation, metal, plastic and polymer filaments, textile fibers, and the like, as well as combinations thereof.
The wire is positioned at a distance from about one-half inch to about 6 inches from the surface of the workpiece
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Semiconductor manufacture 
