Editing Watercolor painting (section)

==Watercolor paint==
[[File:Watercolours.jpg|thumb|A set of watercolors]]

Watercolor paint consists of four principal ingredients:<ref>"It consists of a mixture of pigments, binders such as gum arabic and humectants such as glycerin, which together with other components, allow the color pigment to join and form the paint paste, which we know as watercolor." {{Harvtxt|Viscarra|2020|p=47}}</ref> a [[pigment]]; [[gum arabic]]<ref>"Turner's surviving watercolour palettes have been found to contain various gum mixtures that generally include arabic, tragacanth, cherry or sarcocolla, and traces of added sugar." {{Harvtxt|Moorby|Chaplin|Warrell|Smibert|2010|p=38}}</ref><ref>"Gum arabic tends to dry out in the paint and is quite brittle, so the other main ingredient is glycerine, which keeps the paint soluble." {{Harvtxt|Chaplin|2001|p=25}}</ref> as a binder to hold the pigment in suspension; additives like [[glycerin]], [[ox gall]],<ref>"so ox gall is added as a wetting agent." {{Harvtxt|Chaplin|2001|pp=25-26}}</ref> [[honey]], and preservatives to alter the [[viscosity]], hiding, durability or color of the pigment and vehicle mixture; and, evaporating water, as a solvent used to thin or dilute the paint for application.

The more general term ''[[watermedia]]'' refers to any painting medium that uses water as a solvent and that can be applied with a [[brush]], [[pen]], or sprayer. This includes most [[ink]]s, watercolors, [[tempera]]s, [[casein paint|casein]]s, [[gouache]]s, and modern [[acrylic paint]]s.

The term "watercolor" refers to paints that use water-soluble, complex carbohydrates as a binder. Originally (in the 16th to 18th centuries), watercolor binders were sugars and/or hide glues, but since the 19th century, the preferred binder is natural [[gum arabic]], with [[glycerin]] and/or [[honey]] as additives to improve plasticity and solubility of the binder, and with other chemicals added to improve product shelf life.

The term "[[bodycolor]]" refers to paint that is opaque rather than transparent. It usually refers to opaque watercolor, known as [[gouache]].<ref>{{Harvtxt|Chilvers|2009}}</ref> Modern acrylic paints use an [[acrylic resin]] dispersion as a binder.

===Commercial watercolors===
[[File:Watercolors by William Reeves, London, inventor of watercolors in cakes, undated - Joseph Allen Skinner Museum - DSC07847.JPG|left|thumb|upright|A [[Reeves and Sons|Reeves]] watercolor box]]
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. [[Reeves and Sons|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.<ref>"...more user-friendly soft watercolour blocks had been introduced by the artists' colourman Reeves." {{Harvtxt|Moorby|Chaplin|Warrell|Smibert|2010|p=40}}</ref>

Modern commercial watercolor paints are available in tubes, pans and liquids.<ref>"...in general it can be liquid, creamy in tubes, solid, in the form of pans, chalk pastels, waxes, markers, pencils, etc." {{Harvtxt|Viscarra|2020|p=47}}</ref> 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 (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 technology|industrial]] [[organic chemistry]], the variety, [[colorfulness|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]]. 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 materials]] industry 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 (grinding)|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.

===Transparency===
In the partisan debates of the 19th-century English art world, gouache was emphatically contrasted to traditional watercolors and denigrated for its high [[hiding power]] or lack of "transparency"; "transparent" watercolors were exalted. The aversion to opaque paint had its origin in the fact that well into the 19th century [[lead white]] was used to increase the covering quality. That pigment tended to soon discolor into black under the influence of sulphurous air pollution, totally ruining the artwork.<ref>{{Harvtxt|Kraaijpoel|Herenius|2007|p=187}}</ref> The traditional claim that "transparent" watercolors gain "luminosity" because they function like a pane of stained glass laid on paper—the color intensified because the light passes through the pigment, reflects from the paper, and passes a second time through the pigment on its way to the viewer—is false. Watercolor paints typically do not form a cohesive paint layer, as do acrylic or [[oil paint|oil]] paints, but simply scatter pigment particles randomly across the [[paper]] surface; the transparency is caused by the paper being visible between the particles.<ref name="Kraaijpoel2007">{{Harvtxt|Kraaijpoel|Herenius|2007|p=183}}</ref> Watercolors may appear more vivid than acrylics or oils because the pigments are laid down in a purer form, with few or no fillers (such as kaolin) obscuring the pigment colors. Typically, most or all of the gum binder will be absorbed by the paper, preventing the binder from changing the visibility of the pigment.<ref name="Kraaijpoel2007" /> The gum being absorbed does not decrease but increase the adhesion of the pigment to the paper, as its particles will then penetrate the fibres more easily. In fact, an important function of the gum is to facilitate the "lifting" (removal) of color, should the artist want to create a lighter spot in a painted area.<ref name="Kraaijpoel2007" /> Furthermore, the gum prevents [[flocculation]] of the pigment particles.<ref name="Kraaijpoel2007" />