What is a varnish

Varnish is a protective coating that forms a transparent and hard protective film. Used for wood and other materials. The most common is a combination of drying oil and resin, solvents, or diluents. The lacquer creates a glossy surface on the material, but the new can also be matt or semi-glossy. 

The lacquers are colorless or slightly colored, transparent, pigment-free. They can only be applied as the last layer that forms a protective film. The lacquer on the wood creates a cover that overlays the drawing of wood. 

The lacquer is used on wooden and metallic materials, especially on vertical or sloping surfaces. It can be used both indoors and outdoors. In a quiescent state, the lacquer is a thick gel which is disrupted when mixed and is fluid. When painting, he should not run over the brush.