On an oil painting the layers of paint harden due to a chemical...
On an oil painting the layers of paint harden due to a chemical reaction with the oxygen in the air. As a manufacturer we must always choose an unsaturated oil, that is to say an oil that is still capable of absorbing oxygen from the air and which allows the colour to harden. All the oil colours in the Isaro range are ground in pure linseed oil.
Among the siccative oils that may be suitable for the manufacture of traditional oil colours, linseed oil is, due to its chemical composition, the most siccative. It also has the characteristic of forming a highly resistant protective film (linoxyn). Linseed oil was therefore an obvious choice for Isaro. Linseed oil is sometimes criticized for yellowing; however it should always be borne in mind that this photosensitivity can be reversed. It is due to its high polyunsaturated fatty acid content, which also makes it so siccative. All the pigments used to manufacture Isaro colours are highly resistant to light.