Paint is any liquid, liquifiable, or mastic composition which after application to a substrate in a thin layer is converted to an opaque solid film.

Paint is used to protect, preserve, decorate (such as adding color), or add functionality to an object or surface by covering it with a pigmented coating. An example of protection is to retard corrosion of metal. An example of decoration is to add festive trim to a room’s interior. An example of added functionality is to modify light reflection or heat radiation of a surface. Another example of functionality is the use of color to identify hazards or to identify the function of equipment and pipelines.

As a verb, painting is the application of paint. Someone who paints artistically is usually called a painter or artist, while someone who paints commercially is often referred to as a painter and decorator, or house painter.

Paint can be applied to almost any kind of object. It is used, among many other uses, in the production of art, in industrial coating, as a driving aid (road surface marking), or as a barrier to prevent corrosion or water damage. Paint is a semifinished product, or intermediate good as the final product is the painted article itself.

Paint can also be mixed with glaze to create various textures and patterns. This process is referred to as faux finish and is quite popular with discerning homeowners, architects and interior designers.

The use of Paint is not of recent origin. Ancient peoples, particularly the Egyptians, realized that certain pigments found in the soil could be mixed with a liquid and applied to their buildings. For example, colorful reds and yellows were obtained by mixing ochers with water.

Also, pigments were imported from other countries to supplement those found in the Egyptian soil. From the madder roots, which were imported from India, various shades of red, violet and brown were prepared. And from the indigo plant a deep blue color was produced.

Other civilizations were quick to copy the techniques of paint making developed by the Egyptians. Roman artists made use of the same colors and, with few exceptions, the same methods of producing them. However, after the fall of the Roman Empire of the West in 476 C.E. the art of making paints virtually disappeared.

It was near the end of the Middle Ages that the use of paint for decorative and protective purposes began its reemergence in England. At first paints were used chiefly on churches. Then they were used on public buildings and the houses of the wealthy. Since paint was expensive to produce, it was a mark of social distinction to have one’s dwelling painted.

It was not until the 1700’s that paint was made commercially by a few persons who went into the business in the United States and Europe. These early manufacturers produced only the materials for paint; the painter was required to do his own mixing and formulating. It was not until 1867 that prepared paints were first marketed. The development in the late 1800’s of new machines for grinding and mixing enabled paint manufacturers to turn out large volumes of paint, and soon paint making entered an era of rapid development.

The Ingredients

It is estimated now that most paint manufacturers carry an inventory of almost 1,000 different items. Perhaps as many as 500 of these are in daily use. Great strides have been made in the development of new paints. Indeed, not long ago a popular magazine observed: “Eighty-five percent of the paints on sale today didn’t even exist five years ago.” Yet, paint raw materials might be classified into four main groups:Pigments,vehicles,solvents or thinners and additives.

Pigments are the substances that give color and opacity to paint coatings. The ancients frequently used vegetable and animal matter to color their Paint, but these are of little importance in paint making today. Still used, however, are earth pigments, called natural or mineral pigments. These are obtained from certain earths that are mined, finely ground and refined. But the most commonly used pigments today are chemical ones.

The vehicle is that part of the paint that carries the pigment. It may consist of oils or varnishes. Drying oils that are used in paint vehicles have the property of converting from a liquid to a solid state when exposed to the oxygen of the air. The paint vehicle thus dries and hardens when it contacts the air. The resulting hard film holds the pigment on the painted surface