Cel The objective is to develop a standardized method for measuring environmental deterioration of leather and thus provide a basis for conservation. A project has been set up to identify and quantify the chemical and physical changes which occur in naturally deteriorated vegetable tanned leather due to exposure to atmospheric pollutants and to establish the parameters and conditions of an artificial ageing method which bring about the same changes in new leather as in naturally aged leather.Naturally deteriorated historical leathers have been analysed from libraries in Denmark, England, Wales, France and Holland. The content of sulphate and the pH value reflected the degree of pollution and hydrolytical breakdown of the leather. The visual difference between the very deteriorated leathers from the British Library and those in far better condition from the National Library of Wales were very obvious and were closely related to the difference in their sulphate content and pH values. Analysis of hydrothermal stability gives a measure of deterioration and can be correlated with structural changes in the form of a melting or gelatinization of the fibres observed under the microscope. Analysis of moisture absorption indicated that drastic changes in relative humidity during storage would be likely to induce more stress on the more deteriorated leathers.The oxidative breakdown of the collagen has been detected by means of amino acid analysis and naturally aged leathers are characterised by changes in the amino acid distribution of the collagen. In general these changes are loss of the amino acids arginine, hydroxylysine and lysine, and in many cases of the amino acids hydroxyproline and proline, which are all fundamental for the function and stability of the collagen. There are also characteristic changes of the vegetable tannins, which correspond well with the oxidative changes of the collagen. The amount of extractable tannins from leather decreases with increasing deterioration, and at the same time the amount of breakdown products in the form of monomers increases.Ageing experiments on new leathers have shown that pollution with sulphur dioxide and nitrogen oxides at fairly low relative humidity and slightly elevated temperatures in cycles with dry heat at 120 C, can produce chemical and physical changes which are close to that of natural ageing.The serious deterioration, known as red rot, of many vegetable tanned leather objects, in particular bookbindings, has been known since the last century. The cause of deterioration is ascribed mainly to air pollution. Many attempts have been made to develop ageing methods to examine the durability of leather, and to predict the effectiveness of conservation techniques. None of these methods has been recognized as an acceptable standard. In this project changes of leather structure and properties in naturally deteriorated historical leather are evaluated and quantified by means of different analytical methods. These methods include high performance liquid chromatography(HPLC), gas chromatography-mass spectrometry(GC-MS), isoelectric focusing and other relevant chemical and physical techniques. The historical vegetable tanned leather samples are collected in the 4 participating countries. Ageing trials are carried out in 2 different test plants. Materials used for ageing trials and as controls are vegetable tanned leather and untanned hide prepared specially for the project. Artificial ageing parameters include pollution with sulphur dioxide, oxides of nitrogen and ultraviolet light in atmospheric air at known relative humidities and temperature. The establishment of the criteria and parameters for a standard method of ageing will be based on a comparison of the analyses of the natural deteriorated historical leathers and the artificially aged leathers and hides. Dziedzina nauki natural sciencesphysical sciencesopticsmicroscopyengineering and technologyenvironmental engineeringair pollution engineeringnatural sciencesearth and related environmental sciencesenvironmental sciencespollutionagricultural sciencesagriculture, forestry, and fisheriesagriculturehorticulturevegetable growingnatural scienceschemical sciencesorganic chemistryamines Program(-y) FP2-STEP - Two specific research and technological development programmes (EEC) in the field of the environment STEP/EPOCH - STEP -, 1989-1992 Temat(-y) Data not available Zaproszenie do składania wniosków Data not available System finansowania CSC - Cost-sharing contracts Koordynator Kongelige Danske Kunstakademi Wkład UE Brak danych Adres 34,Esplanaden 1263 København K Dania Zobacz na mapie Koszt całkowity Brak danych Uczestnicy (6) Sortuj alfabetycznie Sortuj według wkładu UE Rozwiń wszystko Zwiń wszystko Central Research Laboratory for Objects of Art and Science Niderlandy Wkład UE Brak danych Adres 1070 AC Amsterdam Zobacz na mapie Koszt całkowity Brak danych Koninklijke Bibliotheek Niderlandy Wkład UE Brak danych Adres Prins Willem Alexanderhof 2509 LK s'Gravenhage Zobacz na mapie Koszt całkowity Brak danych Københavns Universitet Dania Wkład UE Brak danych Adres 2A,Øster Farimagsgade 1353 København K Zobacz na mapie Koszt całkowity Brak danych Leather Conservation Centre Zjednoczone Królestwo Wkład UE Brak danych Adres 34 Guildhall Road NN1 1EW Northampton Zobacz na mapie Koszt całkowity Brak danych MUSEUM NATIONAL D'HISTOIRE NATURELLE Francja Wkład UE Brak danych Adres Rue Geoffroy-Saint-Hilaire 36 75005 PARIS Zobacz na mapie Koszt całkowity Brak danych ROYAL INSTITUTE FOR CULTURAL HERITAGE Belgia Wkład UE Brak danych Adres 1,Jubelpark 1 1000 BRUXELLES Zobacz na mapie Koszt całkowity Brak danych
