Paint is a chemical covering material which forms a decorative and protective layer when it is applied on a surface. Chemicals that form the paint are divided into four groups. These are; resins (binders), pigments, fillers, solvents and solid substances. The component which provides paint to form a layer is called resinous. Drying rate and shape, adhesion, resistance to environmental conditions, hardness and elasticity, yellowing resistance and other properties of the paint are largely depends on the type of resin. The main reason for the use of pigments in paint is the ability of making the paint colorful and opaque. In addition, some pigments absorb or reflect ultraviolet light and delay the deterioration of the resin. Pigments that are defined as Antikorrosive pigments are especially used at the lining layer of paint systems. This will stop the progression of corrosion by controlling the corrosion reactions.
Solvents are used in order to give the paint viscosity, to solve the low fluidity of solid resins, to give fluidity to low viscosity resins. All solvents used in the painting evaporates into the atmosphere after the application of paint.
Other materials used in the painting are additive materials. Additive materials are used in order to improve certain properties of the paint in very small amounts (%0,01 – 2).
Some examples of the additives;
Wetting: eases the dispersion of pigment in the resin.
Crash Preventives: Slows down pigments collapse.
Dryers: dries the paints quicker.
Surfactants: allows the paint to give a smooth surface.
UV Absorbers: delays yellowing of the paint in UV light.
Anti-foamers: prevents foaming during production and application of paints.
Opacifiers: lowers the brightness of the paint.
Thickeners: Sets the fluidity of the paint.