Why Is Linseed Oil Used As a Drying Oil in Paint?

Linseed oil comes from the flax seed.

The oil in oil paints serves four functions. It holds dry pigment and makes its application possible, it binds the pigment in place, it holds the paint to the surface to which it is applied and it increases the richness and tone of the color of the paint. Vegetable oils in general do these things the best, and linseed oil in particular offers advantages over other oils such as walnut or safflower.

Application

Linseed oil mixed with dry pigment creates a smooth and soft paint mixture that you can apply in many different ways. Right out of the tube, you can make beautiful, thick impasto. If you mix it with a solvent such as mineral spirits, you can thin it to a wash consistency.

Binding

Linseed oil binds or holds the pigments in place after it dries. This is the meaning of a drying oil. The oil does not evaporate over time, but undergoes a complex chemical change, transforming into a flexible and permanent material that fixes the pigments in the paint into place.

Adhesive

In addition to fixing the pigments in the paint, the linseed oil will also adhere to the surface on which it is applied. It will stick to canvas or panel immediately, and as it dries it creates a glue-like bond that will hold for centuries.

Visual

Linseed oil, when it dries, helps create the luminous and jewel-like colors that oil paint is prized for. The pigment itself, beginning as a dry powder, needs the oil's richness to bring out its tone.

Advantages

Linseed oil, derived from the flax seed, has several advantages over other oils. It is economical and can be refined to a very pure state. It is almost universally present in artist's oil colors as it does not yellow significantly over time and change the color of the paint. Occasionally, manufacturers will use a poppy oil with a white paint, as it is slightly lighter in color and therefore less visible when mixed with pure white pigments. Artists should only use cold-pressed linseed oil, as heat extracted oils are not as permanent.

References

• "The Artist's Handbook;" Ralph Mayer; 1991