Pen and wash

A wash is a term for a visual arts technique resulting in a semi-transparent layer of color. A wash of diluted ink or watercolor paint applied in combination with drawing is called pen and wash, wash drawing, or ink and wash. Normally only one or two colours of wash are used; if more colours are used the result is likely to be classified as a full watercolor painting.

In painting it is a technique in which a paint brush that is very wet with solvent and holds a small load of paint or ink is applied to a wet or dry support such as paper or primed or canvas. The result is a smooth and uniform area that ideally lacks the appearance of brush strokes and is semi-transparent. In East Asian traditions Ink and wash painting is a very important technique, all applied with brushes, especially for landscape painting.

A wash is accomplished by using a large amount of solvent with little paint. Paint consists of a pigment and binder which allows the pigment to adhere to its support. Solvents dilute the binder, thus diluting the binding strength of the paint. Washes can be brittle and fragile paint films because of this. However, when gum arabic watercolor washes are applied to a highly absorbent surface, such as paper, the effects are long lasting.

The wash technique can be achieved by doing the following:

In interior design, a wash or color wash of paint on a wall can be used to create a textured effect as a faux finish.

In ceramics, a wash is typically a coloring oxide thinned with water applied to the piece to achieve an effect similar to a glaze.

Digital image creation software can have features that simulate the painting technique.

Within cinematic representation of the technique, Alfred Hitchcock used a wash of red over closeup of actress Tippi Hedren in Marnie as an expressionistic representation of the character's emotional trauma.

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