I’m planning some paintings in tempera grassa. I’ve worked before in the medium, using an emulsion of egg yolk and sun-thickened linseed, almost equal parts each but a bit more yolk so it’s water-soluble. The paint had good working properties, but I’d like a bit more hardness and shine, as one would get by adding dammar (which many tempera grassa recipes call for) but which I don’t want to add (because of the negative attributes of dammar). Is there another resin I could incorporate for a similar affect? Would any of the modern synthetic resins be a possibility?
Thanks,
Koo Schadler
I haven’t tried adding an alkyd – I’ll experiment and let you know how it works. Thanks, Koo
Hi Koo
I would not use any of the synthetic resins used in conservation for this purpose, even those known to be compatible with oils. The problem is that their virtue (similar solubility after aging) is their real deficit in this instance. Have you experimented with alkyd mediums for this purpose? I have not performed these tests nor read about any studies, but they would seem a logical replacement. The stability and insolubility of these resins would be greatly appreciated if they work for your technique. In lieu of this and if you really desire the handling and hardness of a resin, use dammar or perhaps even a true copal medium if you have some on hand. The copal will yellow and become more brittle but it does become less and less soluble over time.
No matter what, and as always, please record you medium use on the back of your artwork 😉