Water miscible oil paint

Water miscible oil paint (also called "water soluble" or "water mixable") is oil paint either engineered or an emulsifier has been added, to be thinned and cleaned up with water, thus making it possible to avoid using chemicals such as turpentine, whose fumes may be harmful if inhaled (making it necessary to take precautions, such as using the solvent in a ventilated environment). Water miscible oil paint can be mixed and applied using the same techniques as traditional oil-based paint, but while still wet it can be effectively removed from brushes, palettes, and rags with ordinary soap and water. Its water solubility comes from the use of an oil medium in which one end of the molecule has been altered to bind loosely to water molecules, as in a solution.

The traditional rule of gradation of layers — "fat over lean," or flexible over less flexible — applies to water miscible oil paint as it does to traditional oil, and in this respect the two kinds of paint behave in the same way. However, their handling is slightly different: when thinned with water to a considerably liquid phase, water miscible oil paint tends to feel and behave like watercolor (although, unlike watercolor, and to a greater extent than traditional oil, it may lose adhesion to the ground or support if over-thinned); by contrast, when used as a short paste without water for heavy impasto work, it tends to drag, developing a consistency somewhat "gummier" or tackier than the more buttery one characteristic of oils. At midrange (between short paste and long paste) water miscible oil paint is gouache-like, sharing the properties of both transparent watercolor and opaque oil (in the manner of watercolor, for example, some colors will darken upon drying, the more so as more water is mixed into the paint, and in the manner of oil, the paint film will have some thickness to it). Also gouache-like is the overall effect, which tends to be matte as compared to the glossier oil, but this too is a property that will vary, depending on the pigment used and on any mediums (or diluents) mixed into it, as well as on the pastiness of the paint (as a general rule, the pastier, the glossier). The handling of water miscible oil paint, in summary, changes considerably as it passes from one phase to another: this makes it a versatile medium but, by the same token, it also requires the artist to develop by experience specific skills with which to successfully manipulate it and exploit its range to achieve the desired effect.

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