Linseed oil is an oil derived from the seeds of the flax plant. It is a type of drying oil—that is, it takes in oxygen from the air to form a tough film that resists breaking, chipping, and changes in the weather. Linseed oil is used primarily in printing inks, paints, varnishes, linoleum, and other industrial products. In addition, it is sometimes used as a protective treatment for concrete.
Flax seeds are made up of about 40 per cent oil and 60 per cent water and solid material. To obtain linseed oil, workers grind the flax seeds into a meal and heat it. This meal is then either crushed by a hydraulic press or treated with chemicals called solvents to extract the oil. The oil is refined to remove impurities. Freshly extracted linseed oil is dark brown, but the refined product is light yellow. The remaining meal, which is high in protein, is used as feed for livestock.
Today, synthetic chemicals have replaced many of the uses of seed oil. As a result, world production of the oil is declining.
