Conservation of a Chine-collé Etching by Menci Clement Crnčić

Članak opisuje nova saznanja o tehničkom aspektu grafika Mencija Clementa Crnčića, kao i nove pristupe u restauriranju grafika chine-collé, čiji se nosilac sastoji od dvaju slojeva papira, različite strukture i gramature, spojenih u procesu tiskanja. Opisani su postupci konzerviranja i restauriranja koloriranog bakropisa chine-collé naziva Pod zidom koji je pretrpio znatna oštećenja uzrokovana kemijskim, mehaničkim i biološkim čimbenicima. Uz poderotine, napuknuća i brojna oštećenja površinskog sloja nosioca i medija, estetskom dojmu i vrijednosti umjetnine uvelike su naštetile diskoloracija te masna i vodena mrlja. S obzirom na to da se radi o laminiranom papirnatom nosiocu, poseban izazov u radu bilo je provođenje mokrih tretmana, u cilju uklanjanja mrlja, diskoloracije i kiselosti iz papira, zbog rizika od delaminacije. Nakon opsežnih kemijsko-fizikalnih istraživanja i provedenih suhih tretmana, pokazalo se nužnim (te uz poseban oprez mogućim) provesti tretmane u vodenim otopinama, koji su uključivali pranje, neutralizaciju i izbjeljivanje papira. Izvedena je metoda bijeljenja na suncu, kao najblaža i najsigurnija metoda bijeljenja papira, čija je prednost i to što se izvodi istovremeno s postupkom neutralizacije, u vodenoj otopini kalcijeva hidroksida. Takav pristup rezultirao je uspješnim uklanjanjem mrlja i diskoloracije, čime je postignuto željeno estetsko i strukturno poboljšanje stanja umjetnine.The paper describes the treatment of the chine-collé colour etching Pod zidom, made around 1910 by Menci Clement Crnčić (1865–1930). The artwork was executed on paper with a composite structure, that consists of the imagebearing layer made of thin hand-made paper (chine), adhered to the secondary support (plate paper) made of heavier machine-made paper, during the printing process. The print suffered from severe damage caused by grime, insects, water and inadequate handling and storage. In addition to extensive surface and ingrained dirt on both sides of the paper, nearly the whole top third of the print was significantly discoloured by an oil stain, and the bottom right corner by a water stain (tide line). The paper support became brittle due to acidity, which, in addition to mishandling, resulted in mechanical damage: tears, fraying and cracking, particularly around the margins and in the upper part of the print, with a crack running almost the entire length of the horizontal line. Silverfish (Lepisma saccharina) caused significant abrasion on the top layer of the paper support, on both the margins and the image, leading to several holes, and adding to the paper’s fragility. As the structural and aesthetic aspects of the print were both greatly compromised, the request of the owner, and the goal of conservation treatment, was to strengthen the weakened structure of the artwork, as well as to improve its aesthetic value by reducing discoloration and stains. Due to the delicate nature of the chine-collé print, careful planning and a cautious approach was necessary in order to avoid treatments that might result in the separation of the two sheets forming the paper support. After thorough physical and chemical analysis of both the support and media, followed by the removal of surface impurities using a dry cleaning method, aqueous procedures to reduce the discoloration, stains and acidity proved to be necessary, and actually possible with a sensitive approach. The complex conservation treatment included cleaning with gels and solvents, capillary and blotter washing, deacidification and bleaching. Sun bleaching was chosen as the most sensible treatment method; it is least harmful to cellulose, and simultaneously used for deacidification in an aqueous solution with calcium hydroxide. After the desired aesthetic improvement was achieved, tears and creases were repaired with Japanese paper and wheat starch paste, while the areas of surface loss damaged by silverfish were filled with micro-cellulose powder and thin methylcellulose. An empirical understanding of the properties of the object combined with a careful approach to planning the conservation procedures were key to the success of the project. This approach, which could have compromised the bond between chine and plate paper, ultimately resulted in the successful removal of stains and discoloration, achieving the desired aesthetic and structural improvement of the object