Decorative Paint and Varnish Finishes

Decorative Paint and Varnish Finishes 

coverings that have a pattern, either in relief or in many colors. They are produced by enamel paints, or enamels, usually based on alkyd resins and their combinations with other resins (such as melamine-formaldehyde) or on glycerol esters of rosin and cellulose. The pattern of the finishes is divided into “hammered,” “shagreen,” crackle, crystallized (frosted), wrinkled (moiré), and multicolored.

Hammered decorative finishes resemble a beaten surface, with traces of hammer blows. So-called pattern-makers (most often organosilicon liquids) are mixed with the enamels used for this purpose; the greater the amount of these components, the finer the pattern. Shagreen finishes appear to have the texture of shagreen leather. The pattern is produced by choosing the proper degree of viscosity of the enamel, thickness of the coat, air pressure in the paint sprayer, and other conditions of formation of the coat. Crackle finishes, which have the appearance of crocodile skin, are produced by using enamels with a high pigment and filler content. Upon drying of such enamels—which are usually applied in several coats—internal pressures arise in the upper paint layers, causing cracks in the coating. Frosted finishes, which resemble the patterns formed by ice crystals on windowpanes, as well as moire finishes, are not widespread, since their production (especially the frosted effect) is accompanied by many technical difficulties. Multicolored decorative paint and varnish finishes are single-layer finishes over which multicolored spots of various shapes are scattered.

Some decorative finishes, such as hammered, shagreen, and crackle, are not only decorative but also have a protective function, which makes possible their use in finishing metal articles, machines, and instruments. Decorative paint and varnish finishes are also applied to articles made of wood and to walls, which usually makes it possible to avoid labor-intensive and expensive priming operations such as puttying, since decorative coatings hide many defects of the painted surface—traces of mechanical processing, corrosion, and so on.

REFERENCES

Payne, H. F. Tekhnologiia organicheskikh pokrytii, vol. 2. Leningrad, 1963. (Translated from English.)
Drinberg, A. la. Tekhnologiia plenkoobrazuiushchikh veshchestv, 2nd ed. Leningrad, 1955.