From hide to leather, process involves lots of resources, energy and manpower, Upcycling is a better option compared to recycling of leather garment waste wherever possible.
Though Upcycling is done in India , the products are either exported or sold in local lower end of the market. The quality and finishing of the products sold in India are low and does not match the requirements of current trend and market.
What is leather?
The Standard Definition of leather is Hide or skin with its original fibrous structure more or less intact, tanned to be rot proof. The hair or wool may, or may not, have been removed. It is also made from a hide or skin that has been split into layers or segmented either before or after tanning.
The history of leather
Primitive man hunted wild animals for food, he removed the hides and skins from the dead animal carcass and used them as crude tents, clothing and footwear. The earliest record of the use of leather dates from the Paleolithic period. Cave paintings discovered in caves near Lerida in Spain depict the use of leather clothing. Excavation of Paleolithic sites has yielded bone tools used for scraping hides and skins to remove hair.
The skins rapidly putrefied and became useless, so a method of preservation was needed. The earliest method was to stretch the hides and skins on the ground to dry, rubbing them with fats and animals brains while they dried. This had a limited preserving and softening action. Primitive man also discovered that the smoke of wood fires could preserve hides and skins, as did treating them with an infusion of tannin containing barks, leaves, twigs and fruits of certain trees and plants. It seems likely that man first discovered how to make leather when he found that animal skins left lying on a wet forest floor became tanned naturally by chemicals released by decaying leaves and vegetation. Much later the use of earth salts containing alum as a tanning agent to produce soft white leather was discovered. The alum leathers could be dyed with naturally occurring dyestuffs in various plants.
Wall paintings and artifacts in Egyptian tombs indicate that leather was used for sandals, clothes, gloves, buckets, bottles, shrouds for burying the dead and for military equipment. The ancient Greeks and Romans also made extensive use of leather and it has remained an important industrial raw material since those times. The Romans used leather on a wide scale for footwear, clothes, and military equipment including shields, saddles and harnesses. Excavation of Roman sites in Great Britain has yielded large quantities of leather articles such as footwear and clothing.
The manufacture of leather was introduced to Britain by invaders, the Romans, and by religious communities, whose monks were experts at making leather, especially vellum and parchment for writing purposes. The ancient Britons had many uses for leather from footwear, clothing and leather bags, to articles of warfare. The hulls of the early boats, known as coracles, were also covered in leather. Through the centuries leather manufacture expanded steadily and by mediaeval times most towns and villages had a tannery, situated on the local stream or river, which they used as a source of water for processing and as a source of power for their water wheel driven machines.
Composition of leather:
There are basically just three main materials from which hides and skins are made, Water(60%), protein(25%) and fat(15%).
The protein is mainly collagen (found in many cosmetics) and it is this collagen that is transformed into leather by the tanning process.Raw hides and skins have four main parts - an epidermis, grain, corium and flesh. Two of these layers - the epidermis (which is a thin protective layer of cells during the life of an animal) and fleshy remains - are removed during tanning by a process called liming. This leaves just the grain and the corium.
The grain layer is made of collagen and elastin protein fibers (found in many moisturizers and facial creams), and its structure varies quite a bit depending on the age, breed and lifestyle of the animal. The grain carries many distinctive marks such as insect bites, growth marks and wound scars giving the leather a unique appearance.
The corium is packed with collagen protein fibers, arranged in larger bundles and interwoven to give the structure great strength, excellent elasticity and durability. The thickness of the corium increases with age which is why calfskins are thinner, smoother and softer than the hides of mature animals. Hides from cows are smoother, thinner and softer than the hides of mature male bull hides which are thick, tough, course grained and very strong. Thick hides are often too thick for their end use and so they sometimes have to be split layer wise through the corium which is used mainly as suede leather. The uncut corium layer with natural grain layer is called as Napa. Also an artificial grain layer to the flesh split is applied to make it look like grain leather or Napa. However the strength of the suede is reduced compared to Napa since the corium lacks the strength of the corium found in the grain layer.
Different hides used and why:
Cowhide and, to a lesser extent, bull hide, are raw materials with the thickness and intrinsic collagen fiber structure to make strong, dense leather after appropriate tanning processes, for many uses, in varied industries. In fact, most cowhides, and almost all bull hides, are so thick along the spine, that they are routinely reduced in thickness by a process called skiving, to enable their use in upholstery, luggage, clothing, and footwear applications. Pigskins, goat skins, sheep skins, and deer skins are much thinner, and have a less dense fiber structure. It is hard to skin a pig intact, in fact, much of the commercial products in pig skins are so thin, they can be diverted for higher value human food products. All goat skins, lamb skins, sheep skins deer skins are not dense, fibrous tissues naturally, and are most valued in applications where their supple, stretchy nature has value, as in gloves, slippers, and shoe and garment linings.
Chicken skin is just too soft and not nearly fibrous enough to make good commercial leather. And, its value as human and animal food far exceeds its value as leather stock. Some birds, like the ostrich and emu, do yield skins with enough collagen fiber tissue to make worthwhile leather, and are highly priced, especially in footwear and luggage applications, for their unique spotted appearance (due to the quill pores) and color. Some fish, including sharks, rays and the scale less relatives of lungfish such as eels, can be skinned, and the skins carefully turned into specialty leather, by salt tanning or chrome tanning processes. The old salt pit methods for tanning shark skin are so heavily stinking, that they've ceased production entirely, except, perhaps in some tribal areas in Brazil or Africa. What shark skin we get commercially today, is generally politely and commercially chrome tanned in small pieces from frozen carcass waste.
Seal skin, walrus skin, whale skin, and dolphin leather have very small commercial markets, but out of these, seal skins are still the most valued. The 2004 seal harvest was worth only $16.5 million CAD, according to Canadian authorities, however, which, on a worldwide basis, is insignificant, compared to more commercial sources of skins for leather, such as cowhide.
However, the primary value for any animal, to humans, is still food. Even rattlesnakes and alligators bring more for their meat, than for their hides, hides traditionally being offal. Offal dealers very well know that old offal stinks to high heaven, and is a cost to its owners, in terms of disposal. Thus, offal dealers, including those setting the markets for raw skins, are always willing to let the current crop of hides, renderings, and offal sit, against a lower price they offer. Except perhaps in exotic categories, like snake skins, and some shark and fish skins, where there is no commercial market for the meat due to foul taste or questionable palatability.
Processing of leather (tanning)
The pre-1900 tanning process of crude leathers involves air or salt drying of the animal skin, which was then tanned with vegetable tannins or oils. First immersing the raw hides and skins in a fermenting solution of organic matter in which bacteria grew and attacked the hides or skins, results in loosening of the hair or wool and also dissolves some of the skin protein. The hair or wool is then scraped off with primitive blunt stone or wooden scrapers. The fat or meat still adhering to the flesh side was removed in a similar manner. Tanning, the conversion of pelt into leather, was done by using tannic acid from the hardwood trees, but the explorers also learned brain tanning from the Mandan Indians. This is the process where they take the animal brain, smash it up and boil it in water to make a paste. After boiling, the mushy solution is allowed to cool down, enough to smear it onto the hide. Fold or roll the hide in the brain solution and let it sit overnight to soak. The rule of thumb is that each animal has enough brain to tan its own hide.
Further additions of ground bark/organic solutions were made from time to time until the tannin solution had penetrated right through the skin structure, taking up to two years for very thick hides. The leather was then hung up for several days in open sheds. The hide is then stretched until it becomes completely dry. This is done by hand. If stopped before it is absolutely dry, it will stiffen up and it will have to retanned all over again. The hide is then smoked over a very smoky but not hot fire. It is done until the entire skin has a nice brownish color. The smoking permanently preserves the skin so that it can get wet and not stiffen up. Then the dressing of leather is done which involves paring or shaving it to a level thickness, coloring, treatment with oils and greases, drying and final treatment of the grain surface with waxes, proteins such as blood and egg albumins, and shellac to produce attractive surface finishes.
During the middle ages leather was used for all kinds of purposes such as, footwear, clothes, leather bags, cases and trunks, leather bottles, saddlery and harness, for the upholstery of chairs, and couches, book binding and military uses. It was also used to decorate coaches, sedan chairs and walls. Many leather articles have been recovered from the Mary Rose, a Tudor vessel which sank in 1545.
The majority of the leather was tanned with oak bark, but soft clothing, gloving and footwear leathers were tanned with alum, oil, and combinations of these two materials.
With the discovery and introduction of basic chemicals like lime and sulphuric acid, tanners gradually abandoned their traditional methods and leather production slowly became a chemically based series of processes. Sir Humphrey Davy, the inventor of the miner's safety lamp, investigated some of these processes.
The growth of industrialization in the 18th and 19th centuries created a demand for many new kinds of leathers like belting leathers to drive the machines being introduced into industry, special leathers for use in looms in the textile industry, leathers for use as diaphragms and washers, leathers for use in transport and for furniture upholstery.
At the end of the nineteenth century, the invention of the motor car, modern roads, new ranges of coal tar dyestuffs, the demand for softer, lightweight footwear with a fashionable appearance, and a general rise in the standard of living created a demand for soft, supple, colorful leather. The traditional vegetable tanned leather was too hard and thick for these requirements and thus, the use of the salts of the metal chromium was adopted and chrome tanning became the tannage for modern footwear and fashion leathers. It produces soft, supple, beautiful and fine leathers.
Importance of leather Industries in India:
When we see the history of leather in India, it was constrained to a certain class of people. Tanning was done by a distinct caste called “Chammars” which has reference in Rig-veda. The skin cuts the vibration and effect of what happens in the past, after which if one sits on that spot to meditate, one does not get affected by the doings of the past. This is the reason of usage of animal skin in ancient India only by certain class of people.
Historically though tanning of leather was practiced by untouchables, through imperialism the leather industry got introduced to India and south India in particular due to the access to harbors by British, French and Portugal. India with its largest livestock population in the world makes it rich in raw material resources. Diversified caste systems in India also helps in the availability of different hides like cow, sheep, goat, pig etc. The temperate land in India which is a prime criterion for tanning, crafted a niche for the industry to draw attention of the West to reap the benefit from this God gifted land of animals. The growth of this industry from the yesteryear has been gradual yet phenomenal. From being a mere manufacturer of semi finished leather more than a century ago it climbed up the ladder. The industry grew so much that it had to import raw material to bridge the demand-supply gap. The Govt. policies changed in mid 80’s, which eventually banned the export of the semi finished leather. This policy came as a blessing in disguise that forced the tanners to move the ladder up ahead in their processes, ultimately giving much more value addition to their own products thereby increasing manifold times the revenue from foreign trade. This sparked the boom in the industry in the late 80’s where this cottage industry moved to be called small and now medium and large scale industries.
In the past one decade the government has been encouraging the modernization of Tanneries and FDI(Foreign Direct Investment). This may be because of high competition from China. All the leather manufacturing countries faced the problem of extinction because of Chinese cheap labor and less expensive products. This was countered by India by its quality products. Now only Vaniyambadi town contains more than 100 tanneries (both wet and dry tanneries).
Today the Leather Industry holds a prominent place in the Indian economy. This sector is known for its consistency in high export earnings and it is among the top ten foreign exchange earners for the country. The major production centers for leather and leather products are located in Tamil Nadu – (Chennai, Ambur, Ranipet, Vaniyambadi, Trichy, Dindigul), West Bengal –( Kolkata ; Uttar Pradesh – Kanpur, Agra & Noida), Maharashtra – (Mumbai),Punjab – (Jallandhar) ; Karnataka – (Bangalore) ; Andhra Pradesh – (Hyderabad), Haryana -( Ambala, Gurgaon, Panchkula and Karnal) and Delhi.
Alternatives to leather in the market:
Composting leather (Eco leather): A man-made alternative to traditional leather that is made from discarded leather off-cuts. The process of making composition leather is eco-friendly as it recycles waste leather that is normally sent to landfill and uses just water alone (rather than resins and glues unlike bonded leather) to bind the fibers together. The fibers are combined with a high-tensile textile core and sealed to maintain strength and durability. This leather weighs 40% less than traditional leather, this is then finished to add color, grains and textures plus specific performance requirements such as scuff protection and fire resistance.
Polyurethane: These leather look a likes are considered safe, as this is considered as an eco friendly option.
PVC (Poly Vinyl Chlorate): This non eco friendly option is used most widely and is inexpensive too. Although PVC is an animal-free choice to leather, it does contain petroleum together with other toxic chemicals. These products contained shockingly high levels of chemicals which could be usually a recognized toxin linked to some host of health problems like cancer, infertility, and Alzheimer's.
PVC is a plastic material and it is not usually recyclable because of which it usually sits in landfills. PVC is normally a waste nightmare adding to the carbon footprint that just won't go apart at any time inside the next 100 many years or so.
References
http://www.wikipedia.org/
http://articles.timesofindia.indiatimes.com/2011-02-05/style-guide/28370643_1_leather-bags-colour
http://www.suite101.com/content/history-of-leather-making-a123901
http://www.managementparadise.com/forums/articles/20769-overview-leather-industries-india.html
http://EzineArticles.com/?expert=Lynda_Lacroix
www.barefootleather.co.uk
http://www.indianmirror.com/indian-industries/leather.html
http://www.leatherresource.com/history.html
http://www.leathercraftsecrets.com/leatherwork/tooling.htm
http://whttp://www.hayden-fan.net/category/leather/ww.ecodomo.com/faq.html#1
http://compositionleather.com/glossary#aniline%20leather
http://www.all-about-leather.co.uk/what-is-leather/where-does-leather-come-from.htm
http://www.eleathergroup.com/
http://www.hayden-fan.net/category/leather/
http://wiki.answers.com
http://www.lycos.com/info/leather--people.html
http://www.ivy-rose.co.uk/Articles/recycling-and-upcycling
http://progressivetimes.wordpress.com/2010/02/17/recycling-vs-upcycling-what-is-the-difference/
http://www.ivy-rose.co.uk/Articles/recycling-and-upcycling
http://progressivetimes.wordpress.com/2010/02/17/
http://www.youtube.com/watch?v=ufZix3J3S1g&feature=related
Cradle to Cradle: Remaking the Way We Make Things
by William McDonough and Michael Braungart
Mohammad Javed (leather scrap collector), Vaniyambadi
Sridhar Shenoy (Quality control Dept.), Vaniyambadi
Srikant Kumar (Managing Director), Broadway fashions Pvt. Ltd, Bangalore
Roopa M Patil (Merchandiser), Namaste garments, Bangalore
Rakesh K R ,Sales manager, TVS motors
Eco leather
A man-made alternative to traditional leather that is made from discarded leather off-cuts.
The process of making composition leather is eco-friendly as it recycles waste leather that is normally sent to landfill and uses just water alone (rather than resins and glues) to bind the fibers together.
The fibers are combined with a high-tensile textile core and sealed to maintain strength and durability.
Any required color, texture and grains can be added including specific performance requirements such as scuff protection and fire resistance.
This leather weighs 40% less than traditional leather.
