Paint is a very complex material consisting of many components. Modern paints can have ten to twenty components, each responsible to give a specific quality to the paint. However, basically all paints consist of the following five components.
1. Base Pigment
White lead, red lead, aluminium powder, etc were the pigments that were used initially in oil paint. These materials form the bulk of the paint in a finely divided state. It gives the durability and protection to the painted surface as they have high resistance to the elements. The base should suit the material to be protected. For example, white lead gives no protection to steel. It is used only for wood work. Red lead base is used for steel.
2. Vehicle or Binder
Materials like linseed oil when used as binder facilitate the spread of the paint and also bind the paint and the surface together. Binder can be oils, resins, and bitumen or cellulose derivatives.
3. Solvent or Thinner
It adjusts the viscosity of the paint to suit the method of application. Turpentine is generally used as a thinner in oil paints. In emulsion paints, water is used as a thinner.
It accelerates the process of drying of the paint. Substances like cobalt, lead, manganese dissolved in volatile liquids are used as driers.
5. Colouring Pigments or Extenders
They are added to give colouring and may also act as partially cheap substitute for the expensive base pigment.