The History of Coated Abrasives

The origin of coated abrasives is lost in antiquity. Their development through the ages is the result of the work and contributions of many people. When and where coated abrasives were invented, and when they were first introduced into this country, cannot be answered authoritatively. Coated abrasives have evolved from technological developments to which many people have contributed, rather than from a single invention. As a background for the lessons to follow, a short outline of their development may be helpful.

Dried fish skins were used at an early date for smoothing and polishing wood. This was improved by the development of "shagreen", a material originally made from the skin of certain species of rough scaled sharks. Later, shagreen was made from other types of skins into which a granular material, such as seeds, had been worked to produce the characteristic roughness. It was used both as an abrasive and as an ornamental material depending on the texture. It was in common use in the 16th century as shown by the introduction into the English language of the word "shagreen" at that time. This was an anglicized version of the French word "chagrin", meaning to vex or annoy.

The abrasive paper was sold in the streets of Paris in 1769 as illustrated by an old print of that date, but it is not known how it was made. The first known article describing a method of making coated abrasives was published in 1808. Calcined and ground pumice was mixed with varnish and spread on paper with a brush. Emery cloth was invented in England in 1831 by Lothrop. He used sand, powdered glass, or emery mixed with glue. This mixture was spread on cotton cloth.

A man named Fisher was granted a United States patent in 1835, for a machine and a method for making coated abrasives. Steam was allowed to act on the uncoated side of the paper to prevent curling. The sand was sprinkled from a sieve onto glue coated paper carried by an endless belt. In 1844, Fremy in France began the commercial manufacture of glass and emery paper with a machine of a somewhat different design than the one for which he obtained a patent. In 1856, emery paper of graded degrees of fineness was manufactured in England. Powdered emery was blown into a chamber in which glue coated sheets of paper were hung at various heights. The highest paper received the finest dust, while the lower sheets received the coarser dust. In 1861 a German patent was granted on a flint abrasive paper.

In recent years development work has been done in many countries, and vast improvements have been introduced until coated abrasives have become known as the "Modern Tool of Industry".

In the manufacture of commercial abrasive products, seven distinctly different abrasive materials are employed. In order of their respective hardness (soft to hard), these are crocus, flint, garnet, emery, zirconia alumina, ceramic, aluminum oxide, silicon carbide, and diamonds. The majority of modern coated abrasives have working surfaces of man-made abrasive minerals which are harder, tougher, and sharper than anything nature has to offer except for the diamond.

The bonding materials holding the minerals to the flexible backings, and the backings themselves, have been specifically developed to meet the rigorous demands on these modern tools. The manufacturing controls of coated abrasives are now so great that the consistency of any one product is almost invariably better than that of the material on which it is being used.

Coated abrasive products are employed in the manufacture of almost every product used, whether in the factory, the office, the home, or on the farm. They are used on products on the land, in the air, and on the sea. Even in the rare cases when coated abrasive products were not used directly to make a product. The machines that made the product were themselves usually brought to accurate and polished perfection with the aid of coated abrasives in one form or another.

The coated abrasive industry is very competitive and has become highly technical. During the third quarter of this century, and more particularly over the last 10 years, the coated abrasive industry substantially expanded the use of its products by developing many new and improved items as well as many new end uses for them. There are probably some 40,000 different specifications of these products made and sold by the industry today, as compared to but a few thousand at the beginning of this expansion.