That Colorful Coating Paint

IT ADDS color to rooms in our homes, schools, offices and factories. Automobiles and toys are made attractive by it. It protects buildings, farm machinery and tools from the wind, rain, and heat from the sun. Truly, that colorful coating, paint, is enjoying wider popularity than at any time in history.

Thousands of millions of dollars annually are spent for it; Canadians alone lay out almost 200 million dollars a year for paint. In Canada more than 150 paint plants produce this colorful coating. And in the United States over 635,000,000 gallons of paint are sold by manufacturers each year. That is enough paint to cover some 11,400 square miles, or an area almost the size of the Netherlands!

Thousands of Years of Use

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 paints, 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.

Perhaps the most common thinners for paint are either water or turpentine. These are added to thin the paint to the proper viscosity or thickness for easy spreading on a surface. Although thinners, too, might be considered part of the vehicle, they function somewhat differently in a paint. They begin to evaporate after application of the paint on a surface, leaving the film-forming material exposed for permanent drying.

Paint additives often include compounds of lead, manganese or cobalt. These accelerate the drying of the paint.

How Paint Is Made

Paint is basically a dispersion of colored pigments in a vehicle or liquid medium. The paint maker prepares a rather heavy paste by mixing together dry pigments and a portion of the vehicle. This process might be compared with what a housewife does when she mixes ingredients with her mechanical mixer, perhaps in preparing cake batter. In paint making the mixing cycle is continued until a fluid but somewhat lumpy paste is formed.

The next step requires what is known as grinding. A roller mill of steel cylinders that rotate against each other is frequently used for this. The purpose of the grinding is to pull the pigment particles apart so that each particle will be coated by the resinous vehicle. Another type of mill consists of a revolving drum partly filled with steel balls. By constantly revolving for many hours, the steel balls are able to disperse the pigment particles throughout the vehicle.

After the grinding process, the balance of the vehicle as well as the solvent thinners are added. Also, driers often are added at this time. But when the enclosed steel-ball mill is used, all ingredients generally are included from the beginning. Of course, with the development of water-base paints new types of equipment are used for dispersing pigments and liquids. Tinting of the batch comes next, adding just the proper amount of color to give the batch the exact shade desired. Finally, the paint is moved to automatic machines that fill, cover and code the containers.

The Colors to Use

Since all of us enjoy pleasant surroundings, it will be of interest to consider how you might add pleasantness to your home by employing that colorful coating—paint. Home decorators usually choose colors that will complement other articles in a room, such as those in furniture, rugs or draperies.

Light colors in a small room will create an impression of size, a point to remember when decorating apartments. A continuous flow of neutral tints through several rooms adds an air of spaciousness, inviting one to accent these tints with colorful rugs, cushions or pictures. Keep in mind, though, that an excessive number of colors in any one room can give a cluttered look.

Here are additional helpful hints: Tints of yellow, peach and rose are warm colors. They create a comfortable and mellow charm in rooms facing north and east. Greens and blues in their pastel tones are pages from the marvelous creation around us. One can just feel the cool, relaxing atmosphere imparted by these colors in rooms facing south and west. Rich, bright colors, such as reds and oranges, are exciting colors. But a word of caution. One might tire of them easily. They have a stimulating effect, often reflecting youthful personality or that of one who likes change. Therefore, they often can be suited to the bedrooms of children.

When choosing colors, remember that when a paint is spread over a large area it will appear darker than it does on a small color sample. Therefore, select a lighter shade and it will probably be the color you desire when it is applied to a wall. Also, since colors change under artificial light, it is wise to observe color samples both in daylight and in night light.

Selecting the Proper Coating

Paint is made in a number of finishes, ranging from a high gloss to a flat finish. Generally a low gloss or flat finish will give the most pleasing appearance on a large surface. Flat paints have a greater proportion of pigment to binder, hence they have a rougher finish that scatters the light in all directions. Thus, fewer surface irregularities will show when using a flat paint. However, flat finishes have the shortcoming of being more subject to soiling, and are more difficult to clean.

Thus, if frequent cleaning is necessary, as in a kitchen, bathroom, hallway, or in cupboards and on wood trim, it would be practical to apply a semigloss or highgloss paint. Semigloss would seem to be a compromise that will afford ease of cleaning and will not reflect too many surface imperfections.

In living rooms and bedrooms, a pleasing appearance often overshadows serviceability. Hence a home decorator might choose a flat finish. In the closets, though, where there might be a tendency to mark up the walls, a semigloss paint will make for easier cleaning and a brighter appearance. But since a flat paint has more hiding power and thus often requires but one coat, this is something to consider if time and cost are factors.