BY CHRISTINE ALFORD
This self portrait of Leonardo da Vinci is fading with time, although the Renaissance mans’ reputation will never fade. Leonardo da Vinci was the typical ‘Renaissance Man,’ having skills in many different areas of study. As well as being one of the most famous artists in the world, he was also a prolific inventor. He drew many sketches and diagrams of flying machines, helicopters, an armoured tank and even a robot knight! Most of these inventions were never built as Leonardo da Vinci either lost interest or could not find the money to construct them. He was involved in so many other sculptural, scientific and engineering projects that he only finished a few paintings.
Scientists have developed new techniques to understand why old paper fades to that distinctive yellow colour. Joanna Lojewska, a Chemist from the Jagellionian University in Krakow, Poland explains the process:
‘During the centuries, the combined actions of light, heat, moisture, metallic and acidic impurities, and pollutant gases modify the white colour of ancient paper’s main component: cellulose. This phenomenon is known as ‘yellowing’, which causes severe damage and negatively effects the artwork.’
This self-portrait of Leonardo Da Vinci was drawn in red chalk in the early 1500s. As the centuries have passed, the portrait has faded, and the paper has browned and yellowed. Scientists from Italy and Poland are working together to find out how to save great masterpieces such as this. Most museums now store paintings in carefully monitored stores with controlled environmental conditions to prevent further damage to paintings and ancient artefacts.
Their work shows that the portrait was stored in very humid conditions, which has caused it to fade. Adriano Mosca Conte, a scientist at the University of Rome Tor Vergata, stated that:
‘Using our approach we were able to evaluate the state of degradation of Leonardo da Vinci’s self-portrait and other paper specimens from ancient books dating from the 15th century. By comparing the results of ancient papers with those of artificially aged samples, we gained significant insight into the environmental conditions in which Leonardo da Vinci’s self portrait was stored during its lifetime’.
The scientists have discovered that the state of the degradation of ancient paper can actually be measured by identifying the quantity of chromophores in the paper. Chromophores are the light absorbing particles that are responsible for causing the yellowing of cellulose in ancient paper.
This exciting new research can be used to help us to understand how ancient papers, may fade over time and ensure that other great masterpieces are preserved for future generations to enjoy.