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In the stabilisation of unbound paint layers on paper and fragile papers with misted adhesive solutions, the distribution of the consolidant determines whether the stabilisation treatment is effective. Knowing the distribution of the adhesive throughout the pigment-paper matrix is therefore crucial. It was studied by labelling gelatine and methylcellulose solutions with fluorescent dyes. Their distribution was analysed in thin sections by fluorescence microscopy. The penetration of the misted 0.25-1% adhesive solutions into powdery pigment layers was investigated by simulating gouaches and pastels with a low ratio of binding agent vs. pigment. The penetration of these dilute adhesives into paper substrates was evaluated using four types of paper with different porosities. The following application techniques were compared: repeated applications with and without intermediate drying, applying the aerosol on the suction table and adding alcohol to the consolidant to decrease its surface tension. The results show that the distribution of misted adhesives is governed by the method of application. Drying between applications diminished the penetration of a 1% gelatine solution. The penetration behaviour of the misted adhesives was influenced by the water absorbency of the paper. Porous papers are completely saturated by 0.5% gelatine solutions. On samples with a low porosity, the adhesive was deposited mainly at the surface. Immersing the papers in 0.5% solutions of gelatine or methylcellulose always led to a full penetration of the paper with the adhesive, regardless of the water absorbency of the paper. Aerosol misting allowed a highly localized precise application, making it a suitable method for local stabilisation of media and paper.

AbstractAbout 1400 works on paper in the collection of the Kupferstichkabinett, Staatliche Museen zu Berlin were analysed for sheet dimensions and their aspect ratios and considered for storage- and handling-related damages. A new stacked enclosure system was developed for objects measuring up to 1350 × 950 mm to upgrade flat file storage, to reduce the risk of mechanical damage and improve the ease of handling in the museum study room and for exhibition preparation. Five defined standard dimensions for oversized artworks on paper and for enclosures and frames were introduced at the museum. They reflect the most common aspect ratios of 1:1.4 followed by 1:1.3. The new enclosure system consists of an outer shallow cardboard tray that holds up to five artworks enclosed in a folder. The folders are made either of cardboard, of a corrugated backboard and a cardboard cover, or of a corrugated backboard faced with museum board to which the object can be hinged; the latter serves as a mounting board for framing when the front cardboard cover is folded back. The trays are stackable. The corrugated cardboard walls of the tray retard the transfer of external relative humidity fluctuations into the stacked storage system.

The case study describes the treatment of an etching that had been bleached in the past with 4% hydrogen peroxide and had subsequently suffered extensive colour reversion in the form of foxing and overall discolouration. Staining was most likely caused by the action of hydrogen peroxide on previously unnoticed iron particles in the paper. The print now underwent treatment to stabilize the damaged paper. The print was immersed for 50 seconds in 0.1 M hydrochloric acid HCl (pH 1.1) to extract as much as possible of the iron contamination from the paper; this was followed after rinsing steps by complexation of remaining iron ions through immersion in a calcium phytate solution (1.75 mmol/L, pH 5.3). The treatment, which included extensive rinsing, significantly diminished the foxing stains. No further bleaching treatment was conducted to diminish remaining stains so as not to risk further destabilization of the pre-damaged paper.

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