Maria Trojan-Bedynski, Doris St. Jacques, Lynn Curry and Season Tse: An antioxidant research project resulting from treatment needs of an 18th century illuminated manuscript

The Haggadah prayer book, created in Altona, Germany in 1763, is part of the collection of Library and Archives Canada. This illuminated manuscript contains iron gall ink and numerous illustrations in pigments which include atacamite/paratacamite, a copper containing pigment. Conservation treatment carried out in 1986 included deacidification with WeiT’o, which was unable to completely protect the paper from continued deterioration caused by the pigments and ink. Additional treatment would be necessary to effectively delay the damage caused by oxidation, catalyzed by copper and iron ions in the ink and pigments.

As many elements in the manuscript are water sensitive, only non-aqueous treatments could be considered. The European co-funded InkCor project identified a number of antioxidants that can be used in non-aqueous solutions. Halides were among the most effective for treatment of both iron and copper inks and pigments. Two possibilities of antioxidants were selected for further testing: tetrabutylammonium bromide (TBAB) and 1-ethyl-3-methylimidazolium bromide (EMIMBr).

Laboratory prepared iron gall ink, iron-copper ink, atacamite and verdigris, were applied to unsized Whatman #1 filter paper. Samples were then pre-aged prior to further treatment. Four combinations of antioxidant and deacidification treatments were used: WeiT’o spray followed by TBAB (in ethanol); WeiT’o followed by EMIMBr; TBAB followed by Bookkeeper spray and EMIMBr followed by Bookkeeper spray. The ink samples received post-treatment aging at 80°C and 65%RH for 36 hours; the pigment samples were aged for 7 days. Both the aged and unaged samples were analyzed using colour measurement, zero-span tensile test, and pH measurement. Elemental analyses using inductively coupled plasma atomic emission spectrometry (ICP-AES) was also carried out. This paper will present the test results of the project, evaluate the four antioxidant and deacidification treatment combinations for their suitability in the treatment of the prayer book and discuss the conservation treatments chosen.

For the purpose of an archivist’s publication (which prompted the initial discussion of a need for additional treatment), wine stains obscuring several of the Haggadah pages, were reduced virtually. The Canadian Conservation Institute (CCI) conducted analyses of the paper, ink and pigments and the CCI Oriel Microfade Tester (O-MFT) was used to test the light-sensitivity of the inks and pigments. For the time being, the badly corroded pages of the manuscript were mechanically stabilized with gelatine-coated Berlin tissue (reactivated with 25:75 water:ethanol). Since the manuscript was removed from its original covers and dismantled during the 1987 treatment, the possibility of rebinding the Haggadah has been considered and discussed with book conservators. Their proposal will also be a part of this presentation.