Natural Pigments

The reaction of natural and synthetic mineral pigments with binders containing lipids, such as egg yolk, drying oils, etc., has been reported by various authors.

Generally, the formation of metallic soaps with the free fatty acids in the binders is assumed to be the reaction. These metallic soaps may act as driers, accelerating the oxidation and polymerization ...

Du Fresnoy wrote about colors that appear on the palette of 17th century artists, such as Rembrandt and Rubens, and that appear in Roger de Piles’ translation of De Arte Graphica:
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Where do all the different brands of drying oils in artists’ supply shops originate? Artists’ materials manufacturers do not process their own oil, but rather purchase it in bulk from large industrial sources. For example, there are two major producers of linseed oil in North America and at least two in Europe, but there are many brands of linseed and stand oils offered by artist materials companies. Artist materials companies do not have the resources to process linseed oil, which today is a very specialized and large-scale industry.

About Linseed Oil
Linseed oil is obtained by various methods, including pre-expelling, followed by hexane extraction of the resulting press cake. The oil is refined to ...