Each month, we offer the spotlight to one of our funded researchers to exhibit their research projects in more detail.
The Featured Researcher for November 2023 was Kathryn (Katie) Raeburn McClure with a PhD Project titled Synthetic Caledon textile dyes: development of analytical protocols for identification and colour preservation in heritage collections.
Supervisors: Prof Anita Quye, History of Art, University of Glasgow; Dr David France, Chemistry, University of Glasgow
However, synthetically dyed textiles hold within their fibres little-told stories about human history. Each textile preserves information about the scientific and industrial developments leading to the discovery and manufacture of each component used to make it. It holds information about how and where it was made, and the experiences of the skilled chemists, weavers, and dyers who created it. Within its structure and colour, it also holds visual stories about the history of fashion and design, and information about what the manufacturers wanted to create and prioritise in their work.
My PhD research focuses on a unique, culturally important group of synthetic textile dyes, first discovered in 1901, and referred to by chemists as the ‘anthraquinoid vat dyes’.
Throughout the twentieth-century (and possibly until today), these ‘anthraquinoid vat dyes’ have been considered the gold-standard for ‘unfadeable’ textile dyes. Resistance to fading on sunlight exposure or washing had been a quality that had eluded synthetic dyers before the discovery of this dye group. The reason for this ‘unfadeable’ quality was that these new dyes possessed highly unusual chemical structures, which made them insoluble and chemically stable and thus very difficult to break down or wash off.
Figure 1: Caledon Jade Green (or Vat Green 1), a revolutionary green anthraquinoid vat dye developed in Grangemouth, Scotland.
These unique chemical properties had tangible impacts on how these dyes were used, and how their novel and unique qualities impacted the world of fashion and design. The dyes introduced new hues – most notably a rich green (a notoriously difficult colour to obtain). They allowed for high quality, brightly coloured curtains and upholstery which didn’t fade on exposure to the sun. Above all, their hard-wearing nature changed public expectations about how long textiles can and should last.
Figure 2: Advertisement for Sundour ‘Unfadeable’ Fabrics, dyed with anthraquinoid vat dyes, from The Times, (1924), 04 Nov, 1, available here [accessed 25 Oct 2023].
Alongside this broad-scale impact, the chemical identification of one of these dyes on a heritage textile can also tell us about the object we find it on. Identifying anthraquinoid vat dyes in collections raises questions such as: ‘Why would the manufacturer decide to use this expensive dye?’, ‘Was fade resistance essential to its function?’, ‘Did they require a particular colour only available from this class?’, ‘How will this object react if we put it on display in a gallery or museum?’. Asking these questions can help us to understand and share the stories of the textiles in our collections.
Using the chemistry of these dyes as a key to unlock new information about our past, my PhD research attempts to: reveal stories about the objects in our heritage collections, unravel little-discussed histories of the people and discoveries of science and industry, and inform the preservation and care of precious dyed textiles in heritage collections.
