Archaeology has revealed some great mysteries, from King Tutankhamen’s Tomb to Xian’s hidden Terracotta Army. While many of us have admired these or other ancient treasures, we often give scant thought to how they are preserved for us and future generations to enjoy.
One innovative method of conservation is 3D laser scanning and replication. Recent innovations in 3D printing allow an item to be individually “printed” in 3D materials such as plastics, resins and metals.
As described by the Economist: “Printing in 3D may seem bizarre. In fact it is similar to clicking on the print button on a computer screen and sending a digital file, say a letter, to an inkjet printer. The difference is that the “ink” in a 3D printer is a material which is deposited in successive, thin layers until a solid object emerges.”
In the case of ancient artefacts, the 3D blueprint is created by laser scanning the item, which can then be recreated in high density polyurethane resin modelboard before the finishing touches are applied by hand. Conservation Technologies from the National Museums Liverpool have used this non-contact technology to create a number of impressively accurate copies without any danger to the original item.
Of course, there are more old fashioned uses for polyurethane in the preservation of artefacts. Below, on the left, is the ‘Sea of Galilee Boat’ or the ‘Jesus Boat’ as it is known today. On the right is a picture of the boat, being floated on the Sea of Galilee, 2000 years after it first sunk and was lost in the muddy banks.
The boat was discovered during low tides in 1986. However, with fears of returning waters, dyhydration and disintegration of the wood and damage from locals who believed it contained lost gold, the boat needed to be excavated quickly. It was wrapped in a sheet of polyethylene plastic and then encased in polyurethane spray foam, after which it was refloated onto the Sea of Galilee, all in a matter of 12 days. Following its hasty excavation, it was re-excavated from the polyurethane and submerged in a chemical bath for 7 years before it could be displayed in the Yigal Allon Museum in Israel.
Polyurethane also provides a useful tool for modern avant garde designs for clothing, furniture and technology. Modern artists rely on its versatility to create pieces which are innovative, surprising, deceptive or surreal. Polyurethane is now coming full circle in serving the art of the past as well as the future.