MITRA Forum Question Details

Hello, I hope that a paper conservator will also add to this reply. 
Applying an acrylic medium to the back of on oil-drenched paper isn't something that we'd recommend. The ammonia in the acrylic medium might promote degradation processes (hydrolysis) in the oil paint layers and it's maybe better not to add anything permanent to the reverse when it's not clear if it will help or harm. The majority of conservation literature seems to show that oil paintings on paper are best reinforced by gluing Japanese Paper to the reverse using reversible adhesives. You could use the conservator listings on AIC (American Institute for Conservation) to find a professional paper conservator to work with. Alternatively you could mount your paintings on acid free cardboard to provide a little more support.​​

​The oil would likely have soaked into the fibers of the paper meaning that the medium would only surround the oil penetrated areas, not size them. Sizing is an important step when isolating cellulose from drying oils and we stress this on MITRA. However, the damage caused by oil on cellulose is often over estimated. Oil sticks also contain a lot of wax or other less fluid components which may help mitigate suffusion.