January 4th, 2019
WHY DO WE USE LEATHER?
In the beginning
We know that prehistoric men used animal skins to keep themselves warm and this is the beginning of mankind’s love affair with leather. Like every other species, humans had to forage and hunt for food. Fruit, berries and vegetables were relatively easy to source in the wild, but we also needed protein – and that usually came in animal form – so early man needed to hunt. The animals that he caught would provide meat, and the skins and fur could be used for rudimentary clothing. As livestock breeding became more prevalent, skins were in greater supply and could also be used for making tents.
In future generations, life became more sophisticated and we would learn how to cook our food and also how to process our leather. Unprocessed leather becomes stiff when it gets cold and it rots when it gets warm, so the various things that were done to improve these properties eventually became the basis of the tanning industry. To begin with, animal fats would be rubbed into the leather to make it more supple and durable, but an alternative method was to smoke it over burning leaves and branches. In time, the processes were gradually refined and developed and one of the world’s oldest industries was born.
The next stages
Still in ancient times, it was discovered that the tannin contained in the bark of some trees, notably oak, had a positive effect, as did the use of alum, a mineral which was widely available, particularly in volcanic areas. As the properties of leather became more controllable and its appearance was improved, it became more widely used for footwear, shields and harnesses, furniture, water containers and even as a covering for rafts.
Possibly the biggest changes in the last 100 years or so were the discovery of the tanning power of chrome salts and the replacement of tanning pits with the rotating drums that can be seen in most modern tanneries. These two revolutionary changes shortened the tanning period from months to a few days and led to the growth of a much more productive and efficient industry.
The modern process
The main stages in the modern process are:
a) Curing with salt. To stop putrefaction and infection and remove excess water from the skins.
b) Soaking. In water to remove the salt and bring the moisture content back to a desirable level so that the hide or skin can be treated with aqueous chemicals.
c) Liming. To remove the hair and get the skin into the right condition for satisfactory tannage. The remaining hair is removed by a dull knife or machine (Scudding).
d) Pickling. The skins are treated with a mixture of salt and acid to bring down the pH to a very low level so as to facilitate the penetration of mineral tanning agent into the substance.
e) Tanning. This can be either vegetable or mineral. Vegetable tanning uses tannin, which occurs naturally in bark. Vegetable tanned leather is flexible and is used for luggage and furniture and the soles of shoes. Mineral tanning usually uses a chromium salt. In the raw state chrome tanned skins are blue and therefore referred to as ‘wet blue’. Chrome tanning is faster than vegetable tanning and produces a stretchable leather which is excellent for use in handbags and garments.
f) Finishing. Depending on the finish desired, the hide may be waxed, rolled, lubricated, injected with oil, split, shaved and, of course, dyed. Materials such as suedes and nubuck are finished by raising the nap of the leather by rolling with a rough surface.
So, why leather?
So, now we come back to the original question: Why do we use leather? Or, more appropriately, in an age of modern synthetic materials, why do we still use leather? The short answer to that is simply because, as a material, leather is absolutely brilliant! But the longer answer is a strange one – because it’s born out of compromise. If we think of all the properties that we want our shoes to have, leather isn’t really the best answer for any single one of them.
Fine leather Loake Goodyear Welted shoes
But, if you want a material that is reasonably water-resistant, breathes, is flexible and yet durable, there is simply nothing like leather (particularly a full-grain calf leather). After thousands of years, and in an age when scientists are constantly exploring and discovering new materials, leather, along with other natural materials like wool, linen and cotton, continues to provide an absolutely unparalleled balance of all these features. And, when made into fine, handmade shoes, it can look just great!
Leather ages with dignity and, over time, can take on a lovely patina and character. At Loake we would even go as far as to say that it can, especially when in the form of fine handmade shoes, take on a little of the personality of its wearer.