Hello,
Someone on another forum (who lives in a warm climate) recently mentioned deliberately placing paintings in the sun to speed drying. They do it both when finished and between layers. They mentioned that paint dried to the touch in a matter of hours. It made me curious. It sound convenient but I suspect that there are some inherent dangers to this approach. I looked through the resource documents and there were hints that it was not a best pratcice but I couldn’t find any explicit information. Any insights into potential problems with this practice?
Thanks in advance.
Yes, I had seen that other post and your suggestion to limit sun exposure time – if any. I was wondering if you could expand on the risks posed by “force drying” a painting in the sun.
We recently had a very similar query come in regarding this topic (one that dates back to the time of Jan van Eyck in fact). We recommend reading our response on the other thread which you can findhere and let us know if you have any additional questions.
Probably we should avoid the phrase “forced drying” in this context, and reserve that for paints that either dry by evaporation, or in the case of oil paint, the addition of catalytic metal driers. As you know, oil paints dry by oxidation. In this scenario, the light, and consequent heat, may slightly speed up the oxidation rate (due to the fact that higher temperatures will increase reaction rates) as well as the action of UV light accelerating aging. If taken to extremes, the speed of reactions will be increased more at the surface of the paint than below the surface. This does occur naturally in oil paint films because of the greater availability of oxygen at the surface, but, in theory, you are only exacerbating this with prolonged exposure to heat and unfiltered light.
The effect in reality is probably minimal beyond perhaps jump starting oxidation reactions. I do think that most of the impact of sun is to bleaching out some of the components that contribute to yellowing. Prolonged light exposure should be avoided for obvious reasons including the Increasing fading of sensitive pigments.