How are oil paints made- - National Gallery

The idea of mixing oil with coloured powder, called pigment, to make glossy, slow-drying paint stretches back a long, long way. The oldest known oil paintings date back to the 8th or 9th century, when Buddhists in Afghanistan used oil blended with pigments to make religious murals. Of course, we're not talking about the kind of thick, black oil we use in cars. Paint needs colourless, transparent, drying oils, which are found inside walnuts, or more often in the seeds of the flax plant. When you squash flax seeds with a lot of force, tiny amounts of oil are squeezed out, and if you blend that with the coloured pigment, you get a nice, thick, glossy paint. Sounds easy, eh? We can do that with machines these days. But a long time ago, they relied on grinding the seeds between stones, sometimes by hand, but also in a stone press pulled by animals. Needless to say, you need to use a lot of seeds. Unlike water-based paints, such as egg tempera or watercolour, oil paint dries slowly over time, so artists could blend it on the canvas as they worked. Light interacts with oil paint differently to water-based paint. Less light is scattered from the surface of the pigment particles when they're combined with oil, making a glossy paint with a more intense colour than for the same pigment in water-based paint. So oil colours... The use of oil paints by European artists reached new levels of sophistication in the 13th and 14th centuries, especially in Northern Europe where Flemish painters like Jan van Eyck were able to achieve much more realistic effects and richer colours after blending and layering their paints. Soon enough, its popularity spread to famous Italian painters like Leonardo da Vinci and Michelangelo. Up until the end of the 19th century, to stop their oil paints from drying before they could use them, artists had to store oil paint in pig's bladders, or more cleanly, in blast syringes. But when the tin tube was invented, oil paints could be more easily and less messily carried around. Painters like Vincent van Gogh, Claude Monet and J.M.W. Turner all took full advantage of being able to paint outdoors or en plein air with their handy tube paints. Oil paint is unique, drying slower so that you can blend the paint and create different effects. Artists can apply it thinly and smoothly, or thicker to make visible brush marks, or can build up multiple layers, giving rich colours with a vibrant set unmatched by other artists' mediums.