When automobiles began there was only one seating material considered and it was leather; and that leather was only tanned with vegetable tannins. It is the vegetable tanning process that ages so well and makes leather furniture evolve into that decades old “gentlemen’s club” look of which we are all so fond.
Before automobiles the best such leather was being made for horse drawn carriages and when Rolls Royce began they linked up with a Tanner in the south of England called Connolly, who made a fine line in carriage upholstery leather. For most of the 20th century automobile upholstery remained vegetable tanned, but as demands for lighter weight, anti-fogging and fire retardancy increased a move over to chrome tanning took place. In the 1990s chrome started to lose its place in automobile leather. Some US tanners moved back to vegetable, at least to a degree, but European tanners tended to move to other tanning methods. Sadly Connolly did not survive all these changes as it got into difficulty via a US subsidiary in the late 1990s and closed altogether in 2002.
Not to be deterred Rolls Royce has kept searching for that extra special quality that comes with vegetable tanning and in the developmental electric Rolls Royce produced in 2011 it again returned to a vegetable tannage for the interior. Called Corinova Leather the press release about the new car gets Andrew Monachan, Rolls-Royce Motor Cars General Manager, Leathershop, to explain the leather in detail. “Corinova is an experimental vegetable-tanned leather that allows us to celebrate more of the curves, creases and other features that are part and parcel of the life of the animal. It’s a more sympathetic process that stretches our understanding of Rolls-Royce interior”. This natural vegetable tanning process christened Corinova “gives life to the car, adding definition to the seats, floor and arm rests”.
The press release goes on to explain that most leather produced for automotive applications is chrome tanned. An experimental leather, Corinova distinguishes itself by being entirely chrome free. It starts with a preparation of glutardialdehyde to prepare for tanning. Chestnut extract, sustainably sourced from Southern Europe and Tara powder from crushed fruit of the Tara bush in South America are used for drum-spun colouring. Fruits are harvested without damage to the plant and the product is finished with a combination of natural binders and high tech polymers.
The process lends itself only to certain earthy colours – in the case of Phantom EE a chestnut colour for seat covers and Quebracho Brown for other areas such as the floor and trunk lining, both of which are made of durable saddle leather.
As well as aesthetic differences, Corinova leather presents a number of practical benefits. It uses less paint finish than in standard chrome-tanned leather and creates less waste. It negates the use of petrol-refined products and with further development, it may be possible to use recycled Corinova leather in agriculture to aerate soil.
This is a great return to vegetable tanning for the world’s supreme automobile brand and a sign of the deployment of vegetable tanning back in sectors thought long lost.