Search

The first step in preservative measures for artworks in airtight showcases is the exclusion of outgassing from construction materials or, at least, limitation of the emissions to a minimum acceptable level if the volatile organic compounds (VOCs) generated may be qualified as harmless. Once it is ascertained that the objects in the showcases are responsible for VOC emissions, a step forward becomes necessary, implying showcase ventilation with air flowing through active sorbent materials. Solid phase micro-extraction (SPME) followed by GC separation and MS identification has been applied for checking the outgassing characteristics of different types of materials used for the construction of airtight showcases, and the method was found particularly attractive in terms of speed and sensitivity, suitable for measurements in presence of low-emitting materials. Sampling could also be done in the case interiors, thus making possible detection and recognition of emissions from art objects within a case. A comprehensive preventive conservation scheme has been further devised by means of active air circulation within the showcase and functional sorbent materials along the flow, for complete suppression of gaseous compounds. Control of the compounds in the air flow and of their filtration efficacy was achieved by direct sampling, also using SPME fibers. Continuous monitoring of the air quality in the showcases has been developed with insertion of a photoionization detector capable of detecting the VOCs in the air by inducing molecular ionization, and measuring the generated photocurrent. The system is not selective, but gives the total concentration, reaching ppb sensitivity with high-quality data. In addition it includes temperature and humidity sensors, making the whole a useful instrument for environment control. [ABSTRACT FROM AUTHOR]

Yves Klein's Sculptures-Éponge 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. [ABSTRACT FROM AUTHOR]

Mid-infrared Fourier transform fiber-optic reflection spectroscopy (mid-IR FORS) is a noninvasive and flexible spectroscopic technique. It is ideal in the art conservation field because of its portability for on-site and in situ analysis of art objects, analyses that require delicate handling, or analyses of objects that cannot be sampled. This paper studies the applicability of mid-IR FORS for the characterization of commercial artists' alkyd paints cast on different supports. As predicted, the quality of the spectra and intensity of characteristic peaks varied according to reflectivity, roughness, and materials used in the supports. The presence of organic binder was best identified by its carbonyl peak (the most intense) and CH2stretching peaks; however, this was not sufficient to distinguish between oil and alkyd binders. The differentiation and identification of alkyds and oils must rely on the unique fingerprint peaks. However, in some cases, the fingerprint peaks were difficult to interpret because of strong absorptions caused by inorganic paint fillers, often present in modern paint formulations, resulting in anomalous dispersion and reststrahlen distortions. [ABSTRACT FROM AUTHOR]