Study on laser cleaning of Sculptures-Eponge by Yves Klein

Yves Klein's Sculptures-Eponge are natural sea sponges soaked in International Klein Blue (IKB), assembled on metal pedestals. This work examines the constituent materials, the execution technique and the deterioration problems of the sculptures which are covered by a friable matt paint, in order to define the guidelines for treatment and collections care. For the experimental work, samples were prepared in the laboratory with the same materials and techniques used by the artist. In order to solve problems relating to removal of dust deposits, many aspects were considered in the evaluation process, such as the presence of an organic and porous support, not discussion in the existing literature, the poor cohesion of the surface and Klein's specific recommendations for handling his Monochromes only with gloves, and removing dust while avoiding any contact with the painted layers. Photo-ablation using laser radiation was identified as a possible solution. Three Nd:YAG lasers with different pulse durations (short free-running (SFR), long Q-switched (LQS), and Q-switched (QS)) operating at 1064 nm were tested on two kinds of support (samples of sponges saturated of IKB and glass slides painted with the same color) and on two different types of dirt (one only deposited and another adhered to the support). The interaction of laser radiation with the support and with the paint layers, and the effectiveness of cleaning operations, was monitored with a stereo microscope and a scanning electron microscope (SEM). It was possible to define a method which was then applied for the removal of particulate dirt from a blue sponge stored in the Museum of Modern Art, Turin, Italy.