A very thin paint film applied to the back side of a prepainted sheet specified to have one finished side. The wash coat provides protection in coiling , storage, fabricating and handling.

A coating applied to the back or unexposed side of the strip. Its purpose is to protect the top coat during transit and prevent corrosion of the reverse side. It also provides lubrication for roll forming. It is not closely controlled for color, gloss or applied dry film thickness. Not to be confused with back coat.

A thin solution of shellac, lacquer or other material applied over a stain to enrich it and to stiffen the fibers of the wood so they can be easily sanded. In special cases, a wash coat is applied to the bare wood to prevent succeeding coats from discoloring it or to enable a glaze to be wiped off easily.

Typically uses as the first coat of a finish. The wash coat is used to change the appearance or porosity of a surface.

Extremely thin coating of paint, shellac, varnish, etc. which seals the surface so that the colors do not bleed through the final coat.

A very thin coat of finishing material, usually shellac.