No abstract

The study presents an old icon painted in egg tempera on lime wood, with a poor conservation condition and clogged dirt deposits. The icon is attributed to an anonymous painter of XIXth century and to the neo-classical style of painting. The painting layer was done with only a hand full of pigments, earth colors that were often used in painting the icons from XVIIth to XIXth century in Eastern Europe, that have Byzantine influences. Taking into consideration the nature and the structure of the materials from the upper layers of the painting, affected by deposits of dirt over time, a series of cleaning recipes were studied, using the so called cleaning tests with compatible mixtures of different juices and infusion from indigenes plants, that were freshly done and odorless. A low alkaline 95% ethyl alcohol solution, combined with a few drops of ammoniac 25%, was used as a reference system, due to its compatibility with the greasy deposits found on the polychrome layer and on the wood. The cleaning capacity of the new systems used, in comparison with the standard solution, was analyzed through modern analytical methods of evaluating the degree of cleaning, more exactly by means of visible and UV reflectography, CIE L*a*b* colorimetry by reflection assisted by SEM-EDX and IR spectroscopy.

In order to restore the original aesthetic aspect, to improve the state of the age patina and of the gold halo, similar processes are required. The cleaning process is one of the most important aspects for an artwork and is considering a series of deteriorations and degradations, like dirt deposits (clogged or unclogged) opalescent varnish, colors blackening, burns, blisters, gaps (missing ground, painting layer or varnish). This step in the restoration process includes physical and mechanical proceedings like dusting (with a vacuum), brushing (with a brush), scraping (with a scalpel), removal or polishing etc. The scalpel and the milling process are rough unconventional means that are used only in exceptional cases. The wet cleaning of dirt includes classic washing processes, with water or other complex systems of organic solvents (emollients, surface additives or surfactants, mixtures of solvents). Cleaning the clogged dirt deposits with unconventional methods can be done by means of electronic laser, ion and thermal exchange or ultrasounds. Laser cleaning is often used in removing unwanted dirt deposits from different layers of the art piece. A lot of attention goes towards the controlled elimination of the exterior protection layer (varnish), which can be photo- degraded and oxidized by atmospheric exposure. Visual analysis, with enlargers (OM, SEM, AFM etc.) combined with transmission or penetration techniques (radiography, endoscopy, X-ray diffraction etc.) provides information on the superficial structures of the art work. In order to determine the modifications of the desiccant oils, SEM was used to observed the changes in the morphology of the oil painting layers. Gas chromatography/mass spectrometry (GC/MS) can be used to detrmine detergent residues on the painting layer.

Abstract. Old icons, especially those involved in liturgical rituals are affected in time by external agents factors (temperature, humidity, light, pollution, microbiological attack, abrasion etc.), resulting changes of the appearance and of the structural integrity, dirt deposits, altered varnish and painting layer, cracks, material loss etc. In order to remove the dirt deposits, there are used cleaning systems with dry wiping, vacuuming, scraping, washing with organic solvents, ion exchange solutions, polyelectrolyte, surfactants, and so on, by enzymatic systems or by laser pyrolysis. The last two processes being considered aggressive and highly invasive, although they do clean very well adherent dirt deposits, which strongly degraded the varnish to total blackening (the iconographic image cannot be seen). Based on the literature in the fi eld, regarding the nature of the materials used during the painting process and of the types and structures of the deposits, a series of alcoholic solutions of different concentrations were made, as such or basifi ed, which were compared with ecologic synergic systems based on organic uncolored vegetable juices and decoctions from dried plants. The cleaning effectiveness was done by visual analysis and CIE L*a*b* refl ection colorimetry, space proposed by the CIE (International Commission on Illumination) in 1976, was used. This technique permitting to determine by color deviations the critical point where the patina and polychromes layer.Keywords: degraded varnish, deposits of dirt on tempera, wash tests, solvents, vegetable extracts, decoction of dried plants, CIE colorimetry refl ection L*a*b*. IntroductionTo restore the aesthetics of an old icon, blackened in time and to improve the age patina "the golden halo" of an artifact [1-3] requires some cleaning procedures compatible and highly specifi c for adherent deposits. These operations consider a number of issues related to the value of the artifact, the age, the nature of the materials used in the making process, the effects of deterioration and degradation and the nature and aggressiveness of dirt deposits (loose, clogged -strongly adherent). These deposits lead to the darkened varnishes or bleaching of the paintings, along with the burns, blisters, varnish and paint layer warping, greatly affect the integrity and aesthetics, leading to their removal from the liturgical and museum circuit [4][5][6].Cleaning dirt deposits includes dry physical and mechanical processes, wet physicochemical and enzymatic cleanings, or thermal processes by laser pyrolysis. The fi rst group of methods is based on dust removal processes (vacuum), brushes, scraping (with knife), removal or dry polishing which is used for thick adherent deposits (wax, bitumen , paint and other fatty deposits accidentally splashed, or other type of contact etc.). The wet cleaning is applied frequently when using conventional washing solutions by using water or organic solvents in the form of a synergistic washing complex systems (emollients, surfactants or addi...

Wooden icons used in liturgical activities suffer a series of evolutionary deteriorations and degradations over time, due to improper storage and use conditions. The deterioration of the physical state of the structural-functional elements and degradation of the chemical nature of the components often lead old easel paintings to precarious preservation (almost close to pre-collapse), impossible to use or display as an artifact. In this study was included an old oil-painted icon on a carved linden wood support with fine gilded ornaments, which frames a central icon (“Coronation of Virgin Mary”) and a complex Menaion icon system with iconographic scenes. It was made by an anonymous author and dates back to the late 18th and early 19th centuries. As the icon has a special beauty and an ornamental and iconographic complexity, having a great heritage value, it required the elaboration of an optimal preservation–restoration protocol for the museum exhibition. Initially, the nature of the pictorial materials was determined, and their preservation state was evaluated using the OM, SEM-EDX, micro-FTIR methods, and CIE L*a*b* colorimetry and visible and UV reflectography were used in the evaluation of the wash test and in compatibility studies. Based on the data obtained, the optimal materials and procedures for structural reintegration were selected (including support fillings and filling of gaps), then chromatic reintegration and gilding, followed by final revarnishing, with or without patination additives.