Commercial watercolors

Watercolor painters before the turn of the 18th century had to make paints themselves using pigments purchased from an apothecary or specialized "colorman", and mixing them with gum arabic or some other binder. The earliest commercial paints were small, resinous blocks that had to be wetted and laboriously "rubbed out" in water to obtain a usable color intensity. William Reeves started his business as a colorman around 1766. In 1781, he and his brother, Thomas Reeves, were awarded the Silver Palette of the Society of Arts, for the invention of the moist watercolor paint-cake, a time-saving convenience, introduced in the "golden age" of English watercolor painting. The "cake" was immediately soluble when touched by a wet brush.

Modern commercial watercolor paints are available in two forms: tubes or pans. The majority of paints sold today are in collapsible small metal tubes in standard sizes and formulated to a consistency similar to toothpaste by being already mixed with a certain water component. For use, this paste has to be further diluted with water. Pan paints (actually small dried cakes or bars of paint in an open plastic container) are usually sold in two sizes, full pans and half pans.

Owing to modern industrial organic chemistry, the variety, saturation, and permanence of artists' colors available today has been vastly improved. Correct and non-toxic primary colors are now present through the introduction of hansa yellow, phthalo blue and quinacridone (PV 122). From such a set of three colors, in principle all others can be mixed, as in a classical technique no white is used. The modern development of pigments was not driven by artistic demand. The art materialsindustry is too small to exert any market leverage on global dye or pigment manufacture. With rare exceptions such as aureolin, all modern watercolor paints utilize pigments that have a wider industrial use. Paint manufacturers buy, by industrial standards very small, supplies of these pigments, mill them with the vehicle, solvent, and additives, and package them. The milling process with inorganic pigments, in more expensive brands, reduces the particle size to improve the color flow when the paint is applied with water.