Old oil paintings are suffering from chemical “acne”

WHEN AN OIL portray is dried and completed, it’s supposed to remain that method. But when Ida Bronken, an artwork conservator, started to organize Jean-Paul Riopelle’s “Composition 1952” for show in 2006, she observed drops of moist paint had been trickling down the canvas from deep inside the masterpiece’s layers. Equally odd had been the tiny, exhausting, white lumps poking via the portray’s floor, as if it had a case of adolescent pimples. Different sections appeared delicate and moist; some paint layers had been coming aside “like two items of buttered bread”, Ms Bronken says.