The influence of pollutants on accelerated ageing of parchment with iron gall inks (original) (raw)

A study of the deterioration of aged parchment marked with laboratory iron gall inks using FTIR-ATR spectroscopy and micro hot table

Heritage Science, 2016

A great number of historic manuscripts, drawings, etc., many of which are stored and/or exhibited in museums, archives and various collections contain iron gall inks (IGIs) as base scripting material. Although the severe deterioration effect of IGIs on paper has been recognized and its chemistry has been explored, little focus has been given on IGIs on parchment. A study was designed to investigate laboratory iron gall inks containing ferrous sulphate and gallic acid (LIG formulation) and with added quantities of gum arabic (LIGG formulation). Specimens marked with the above ink types were artificially aged at 80 °C and 80 % RH for up to 32 days. Micro hot table (MHT) thermal analysis showed a decrease in the shrinkage temperatures in inked areas of aged parchment of up to 15.5 °C. Results of FTIR-ATR spectroscopy showed intense migration of sulphate ions from inked spots to neighbouring ink-free areas at the surface of parchment in both ink formulations, also confirmed by SEM microanalysis results. This effect peaked at short-moderate times of artificial ageing, where calcium sulphate was identified and located at the surface of ink-free areas. Moreover, early signs for gelatinization of collagen also resulted from analysis of Amide I and II infrared bands, where the random coil content increased upon ageing as compared to the helical one.

Treat or Not to Treat — That is the Question : Options for the Conservation of Iron-Gall Ink on Paper

2020

Treatment options for iron-gall ink corrosion on paper, including the phytate treatment, were compared and evaluated in a joint research project. Mounting papers from the late eighteenth century offered the chance to test and evaluate conservation methods on naturally aged inks and papers. Samples of newly produced ink on rag paper could be submitted to mechanical testing. The treated mounting papers and the new samples were artificially aged in order to evaluate the long-term effects of treatments. Evaluation was done by visual assessment, measurement of pH, color, scanning electron microscopy (SEM), tear resistance, tear index, folding endurance, micro x-ray-fluorescence analysis (μ-XRF) of iron intensities, x-ray absorption near edge structure (XANES), photometric measurement of cellulose degradation products, determination of carbonyl groups, and molar mass distribution. The results have shown that the combined phytate treatment stabilizes ink corrosion on paper. No additional d...

Room-Temperature Study of Iron Gall Ink Impregnated Paper Degradation under Various Oxygen and Humidity Conditions: Time-Dependent Monitoring by Viscosity and X-ray Absorption Near-Edge Spectrometry Measurements

Analytical Chemistry, 2011

Many western manuscripts were written using iron gall inks. These inks can damage the paper via two major mechanisms: (a) acid hydrolysis, enhanced by humidity, and (b) oxidative depolymerization provoked by the presence of oxygen and free iron(II) ions. The degradation of unsized Whatman paper impregnated with different combinations of iron sulfate, gallic acid, and gum arabic was studied at room temperature in order to assess the relative importance of each mechanism. The samples were stored in various environments including a dry and/or an oxygen-free atmosphere. The cellulose depolymerization was monitored by viscometry and related to changes in the oxidation state of iron, determined by X-ray absorption near-edge spectrometry. The results indicate that residual amounts of oxygen (less than 0.1%) promote cellulose depolymerization, whereas the level of relative humidity has no impact. The cellulose depolymerization also appears closely correlated to oxidative mechanisms. Regarding the oxidation of iron, it only occurs in the simultaneous presence of oxygen and moisture, suggesting the occurrence of rustlike oxidative mechanisms. Finally, the presence of gallic acid has a strong influence, which is only partially explained by its capacity to reduce iron(III) to iron(II).

Study of the copper effect in iron-gall inks after artificial ageing

Chemical Papers, 2018

Iron-gall inks consist of a mixture of vitriols (sulphates of certain metals), gall nut extracts and arabic gum. The association of the iron(II) sulphate present in vitriols, and the gallic acids present in the gall nut extracts induces, after exposure to oxygen, the formation of dark coloured compounds of ink. In addition to iron, this kind of inks contains other metals, such as copper, zinc, and nickel. Among them, copper could be considered the most important because, owing to its catalytic ability, it can be involved in the processes concerning formation and stability of iron complexes, which are responsible for the ink dark colour. For this purpose, four different iron-gall inks containing increasing amounts of copper sulphate were prepared according to a traditional receipt and applied on paper supports. The ink-stained paper specimens were subjected to an intense analytical program to investigate their chemical and physical modifications after artificial ageing (both temperature/humidity and ultraviolet light ageing). The role of copper in the iron-gall inks was evaluated using optical microscopy, colorimetric measurements, X-ray fluorescence (XRF), X-ray diffraction analysis (XRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX) and Fourier transform infrared spectroscopy (FTIR). For the evaluation of the oxidation state of iron and copper, X-ray absorption spectroscopy (XANES) was used. All results indicate that the presence of copper in iron-gall ink causes colour variation, affects the migratory behaviour of iron in the paper, increases the formation of secondary products particularly when ageing process based on temperature/humidity variations is considered.

Historical iron gall ink containing documents — Properties affecting their condition

Analytica Chimica Acta, 2006

Iron gall ink, also referred to as iron gallotannate ink, is one of the most important inks in the history of western civilisation, and was in widespread use from the middle ages until the 20th century. Unfortunately, iron ions and acids present in these inks induce enhanced degradation of paper, thus severely damaging numerous historical artefacts. Yet, when examining documents, it is frequently observed that not all materials containing iron gall ink are suffering from ink corrosion. While some are completely destroyed, others may be in excellent condition even centuries after their creation. In order to establish the main properties of materials, common to severely degraded documents, the effects of the type and quantity of metal ions in the ink, as determined by in-air PIXE method, pH of the ink on paper, grammage of paper, its absorptivity and the width of ink lines were evaluated against the extent of corrosion. Using multiple linear regression analysis, a correlation has been obtained between the width of the applied ink lines, pH, grammage of paper and the extent of ink corrosion. Based on these factors, which can be acquired non-destructively from most historical documents, it is therefore possible to predict the stability of historical iron gall ink containing paper.

Influence of antioxidant and neutralization on stability of historical document models with iron-gall inks

This work is concerned with retardation of the degradation of historical documents written in iron-gall ink. The main objective was to examine the effect of MMMC (methoxy magnesium methyl carbonate) neutralization agent on the stability of the paper substrate during accelerated ageing. Changes were monitored in the mechanical, chemical and optical properties of the paper caused by accelerated ageing by dry hot air (at 105 o C) and wet hot air (at 80 o C and 50% RH). Whatman paper substrate was modified with gelatine combined with aluminium sulphate. The effect of the deacidification agent used, MMMC, and of the antioxidant BHT on the inked paper substrate was determined on the basis of the results of the individual measurements.

Study of Iron Gall Inks, Ingredients and Paper Composition Using Non-Destructive Techniques

Heritage

Old manuscripts are among the most important elements of the cultural and historical heritage of ancient knowledge. Unfortunately, many of them suffer from degradation, mostly those written with iron gall inks. In the present work, a study using non-destructive techniques was designed with the aim of analyzing the elemental composition and structural characteristics of iron gall inks, reproduced in laboratory, paper and their interaction when the ink is deposited on paper, inducing the paper degradation. Proton induced X-ray emission, X-ray diffraction and Fourier-transform infrared spectroscopy provided the elemental and structural information, and photography under infrared (IR) and ultraviolet (UV) light allowed the differentiation between manufactured inks. Results show that the first step of inked paper deterioration is due to acid-hydrolysis of the cellulose and the presence of reactive Fe(II) species by reducing the crystallinity index of the paper, which is affected dependin...