Abstract
Mineral paper, also known as rich mineral paper, is a paper-like material manufactured from calcium carbonate with a small amount of high-density polyethylene (HDPE), instead of traditional cellulose-based fibres. For environmental reasons, mineral paper was designed to degrade when exposed to sunlight. It was the aim of this study to address the research gap in conservation literature describing the properties and degradation patterns of mineral paper. Three mineral paper samples were characterised using visual examination techniques and analysed using Fourier transform infrared spectroscopy with attenuated total reflectance (ATR-FTIR) and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). Calcium carbonate, talc, kaolin, high-density polyethylene and an unknown trace material(s) were identified in these mineral papers. Under accelerated ageing conditions, the mineral paper samples consistently demonstrated a higher rate of chemical and physical degradation compared to a cellulose paper standard when exposed to visible light and ultraviolet radiation. Through this study, a greater understanding was obtained of mineral paper composition, its ageing trajectory, and its response to environmental factors. Further research is required to identify the unknown trace element(s) and whether photo-sensitive additives are present. These results should help to inform the identification, storage, display and treatment of mineral paper-based collections.
Acknowledgements
The authors are grateful to the Grimwade Centre at the University of Melbourne for facilitating the project, Graham Hutchinson at the University of Melbourne School of Earth Sciences for technical assistance with the SEM instrument, and Albertine Hamilton and Marika Kocsis at State Library Victoria for valuable discussions on visual examination. This research was supported by the Australian Government through the Australian Research Council’s Linkage Project funding scheme (project LP160100160) and the University of Melbourne Faculty of Arts Research and Graduate Studies scheme (RAGS). The views expressed herein are those of the authors and are not necessarily those of the Australian Government, the Australian Research Council or the University of Melbourne.
Author Biographies
Cancy Chu is a PhD student at the University of Melbourne researching conservation approaches for plastics in archives. She has completed an MA of Cultural Materials Conservation (2017) specialising in works on paper at the University of Melbourne, and a BA (2015) majoring in Studio Art at Reed College, Portland, Oregon. Her current research is part of an Australian Research Council (ARC) Linkage Project led by Dr Petronella Nel, and is supported by the Australian Commonwealth Government’s Research Training Program and the University of Melbourne’s Melbourne Research Scholarship.
Petronella Nel is a Senior Lecturer at the Grimwade Centre for the Conservation of Cultural Materials of the University of Melbourne. She has a BSc (Honours 1990) in Chemistry, a PhD in Chemistry (2000) and an MA in Cultural Materials Conservation (2006), from the University of Melbourne. She is leading a collaborative ARC Linkage Project ‘A national framework for managing malignant plastics in Museum Collections’. She is interested in developing analytical techniques for characterising materials in order to inform their preservation.