Study of the thermal decomposition of historical metal threads
In this work, it is reported that thermal analysis techniques such as differential thermal analysis and thermogravimetric analysis are very useful for evaluating metals threads and fibres used in the manufacture of historical artifacts. Thermal analysis has been used to characterize the silk, cotton and linen employed as supports and the copper, silver and aluminium as the metallic components in the studied threads. Other organic compounds, mainly added for the conservation of the threads, have also been characterized.
KeywordsHistorical metal threads Metals (Ag, Cu, Al) Cellulosic (linen and cotton) and animal (silk) fibres Organic dyes and mordant Degradation TG–DTG–DTA
The samples were provided by two embroiderers, Fernando Enríquez Morán [http://brenesenlamemoria.blogspot.com.es/2014/10/bordados-fernandez-y-enriquez_5.html] and Eva Díaz Melero, and by Juan Antonio Conde and Antonio Albardonedo (private collections). Samples were collected to aid in the restoration processes of the artwork. The financial support of the Spanish Commission Interministerial of “Economia y Competitividad” (Plan Estatal 2013–2016 Retos–Proyectos I+D+i) under Project BIA2014-55318-R is also acknowledged.
- 1.Braun-Ronsdorf M. Gold and silver fabrics from medieval to modern times. CIBA Rev. 1961;3:2–16.Google Scholar
- 4.Indictor N, Koestler RJ, Wypyski M, Wardwell AE. Metal threads made of proteinaceous substrates examined by scanning electron microscopy-energy dispersive X-ray spectrometry. Stud Conserv. 1989;34(4):171–82.Google Scholar
- 5.Theile, J.M., Guarda, S.O.S., Croquevielle, E., Analysis, conservation and restoration of the metal threads used in Latin American colonial Saints’ robes. In: Proceedings of metal. National Museum of Australia Canberra, Australia; 2004. p. 501–13.Google Scholar
- 8.Bledzki AK. Gassen J (1997) Natural fiber reinforce plastics. In: Cheremisinoff NP, editor. Handbook of engineering polymeric materials. New York: Marcel Dekker Inc.; 1997. p. 810.Google Scholar
- 11.Seonaid MR. Dyes from plants. New York: Litton Educational Publishing Inc.; 1973. p. 32–4.Google Scholar
- 15.Calamari TA, Donaldson DJ, Thibodeaux DP. Distinguishing weathered from unweathered cotton by thermal analysis. Am Dyest Report. 1990;79(7):42–7.Google Scholar
- 18.Sadhir RK, Bajaj P, Singh VP. Effect of oxidizing and reducing agents on indian wools: part III-thermal behaviour. Indian J Fibre Text Res. 1980;5:53–6.Google Scholar
- 19.Hatakeyama T, Lui Z. Handbook of thermal analysis. Hoboken: Wiley; 1998. p. 470.Google Scholar