Reducing Particle Adhesion by Insulating the Original Surface

Reducing Particle Adhesion by Insulating the Original Surface 

In order to reduce the adhesion of dust particles and powders to painted surfaces, the surfaces may be insulated by the application of some sort of thin liquid or solid film or by the use of multilayer coatings. Then the adhesion of microscopic particles will be determined not by the properties of the paint material, but by the nature of the film. When a thin liquid film is applied, we are essentially replacing adhesion in gas by adhesion in a liquid, and this will reduce the adhesive forces (see Chapter VI). 

A thin film of water can be formed on a surface by imposing an electric field. This displaces the positive charges on the particles toward the cathode (substrate), at the same time attracting water, a film of which on the cathode acts as a wetting interlayer and thus reduces the forces of adhesion and friction. This technique can be used in practice. For example, an electrode may be 

The surfaces of railroad cars, vehicles, instruments, and various types of industrial equipment can be protected by means of an emulsion of wax in water, specifically, the protective wax Expotect. After applying the emulsion and drying, the surface carries a coating that acts as a reliable barrier. The wax layer cannot be wiped off manually. Moisture, dust, soot, and other contaminants are kept away from the original surface. The layer of wax is readily removable, taking with it the contaminants that have adhered to the coating [229]. 

Multilayer coatings are used in the atomic energy industry for protection against radioactive substances such coatings are applied to readily accessible surfaces of simple configurations, such as walls, floors, and partitions. When the coating has been subjected to radioactive contamination, the outer layer is easily removed or washed off. Certain special plastic formulations are used in the atomic industry as barrier coatings [230]. 

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