* Posts under ‘Whitney’s Notes’ are for me to organize my notes from conference, my research over special topics and my random work inspired by random things. Please check reference list to find the original content.* 

Posters  I made for leather awareness. Where is leather from, industrially?

Most popular voice:

The global market for beef, and hence hides for leather production, is finely balanced. The supply is clearly based on the demand for beef, rather than the needs of the leather sector. Over recent years, global supply and demand patterns have begun to shift – declining beef consumption in Europe due to various reasons including economic pressures is being offset by rising demand in China. Traditional cattle-exporting countries such as the US are expected to report a slight decline in 2014, while those from South America are predicted to rise, according to the US Department of Agriculture. But while supply and demand patterns are changing geographically, the demand for beef on a global scale is rising – by the end of 2014, global beef and veal exports will have increased by 25% since 2009, according to the US Department of Agriculture.

The livestock and meat sectors should work more closely with leather and other by-product industries to promote how positive whole animal utilisation is across a spectrum of products, including pharmaceuticals and energy as well as leather. One thing is clear, if there is a useful product that can be derived from the live animal and in doing so reduce waste, then that is good news.

The sector does indeed have nothing to hide, in fact, quite the opposite. It produces a whole range of products that the global consumer increasingly demands while all the time striving to improve processes to ensure environmental and social responsibilities are met.Counter argument:

Whether or not you chose to wear leather usually depends on your stance towards meat, be it vegan, vegetarian or carnivore. The issue of whether or not you are at ease with the practices of the meat industry is one for your own conscience: this column aims merely to provide some facts in an area where there is frequent misconception.

Many people happily wear leather on the grounds that it’s a byproduct of animal slaughter for meat and therefore a form of recycling – waste not, want not. But is leather really a byproduct? Yes and no. It might be more accurate to describe it as a subsidy. It’s very hard to get any statistics as the big meat companies are under no obligation to release figures, but the selling of skins can certainly be very profitable for farmers (while meat is not always so). You could therefore argue that by buying leather, you are supporting the meat industry.

Farmers don’t sell hides out of the kindness of their hearts or from a desire to minimize waste. They are in a moneymaking business and need to maximize profits, and the leather industry is worth billions, if not trillions, of dollars annually. The profit depends on the animal involved: while cows, of course, provide most of the leather we use, there’s an increasing demand for more exotic varieties.

Take ostrich, for example – in South Africa, ostrich farms are a developing industry. But there, the conventional picture is reversed: the skins account for some 80% of the slaughtered bird’s value, and it is the meat that is sold as a byproduct. Again, if the bird’s death doesn’t bother you there’s no moral problem, but don’t kid yourself that the leather would have gone to waste if someone didn’t buy it.

Another oddity is that demand is rising for organic or free-range meats, as an increasing number (though still a tiny minority) of people try to source their food as ethically as possible. Yet many of these same people will happily buy cheap leather. This makes no sense: if you won’t tuck into a steak that came from a miserable animal, why buy its skin? Given much of the leather we use comes from countries where animal welfare is firmly at the bottom of the list of priorities, don’t imagine your handbag previously led a happy life.

The softest, most luxurious leather comes from the skin of newborn or even unborn calves, cut prematurely out of their mother’s wombs. Sometimes it will be from the same veal calves whose lives of misery are well documented. Many committed carnivores draw the line at veal: why then wear calfskin?

As I have tried to emphasize, if none of this troubles you then buying leather goods poses no problem. Clearly it would be hypocritical to happily devour a veal escalope but balk at buying a soft leather bag. But if it makes you slightly squeamish, consider cutting down on your leather purchases. If you feel sick, cut out leather altogether. It’s your choice.

You may want to consider the environmental issues before making a decision. The process of tanning leather is incredibly toxic. Most is chrome tanned, which results in carcinogenic chromium (VI) being pumped into the water table. While most factories in Europe and America can no longer get away with this practice, the same cannot be said of the vast leather industry in China, where many bags, jackets, and shoes begin life – including many bound for the luxury market. While leather can be tanned used non-toxic vegetable dyes, chrome tanning is faster and produces a flexible leather that’s better for high-end bags and coats, so there’s no incentive for factories to switch.

So are there any alternatives? Yes, and they’re increasing all the time. Vegetable-tanned or recycled leather is used to make Terra Plana’s ethical shoes, which also feature sustainable rubber soles. Companies like Beyond Skin make shoes from fabrics rather than leather or plastic. And if you’re hunting for accessories rather than shoes, look no further that Matt & Nat, a fantastic company who will provide you with gorgeous bags, purses and wallets.

Of course, PVC and PU plastics used in leather alternatives have environmental problems of their own, which I will come back to in future columns, but many ethical companies, including Bourgeois Boheme, avoid these by using a mix of recycled or biodegradable elements. And before you reply that leather is biodegradable, bear in mind that archaeologists frequently find leather items dating back 12,000 years. That’s a very long time in a landfill.

How is leather tanned?

The tanning process can be defined as a transformation process that reduces the biodegradability of the skin to make it a suitable material for subsequent processing. The tanning process is not a result of modern techniques. Men were tanners much earlier than farmers. After the first attempts at preventing hides from putrefying by using smoke, grease, alum and other agents, the first real tanning was reaches instinctively, and it was vegetable tanning.

Vegetable tanned leather absorbs the traces of out life; it matures, it tans under the sun, it reveals the signs of time and use as the most personal expression of naturalness and truth.

Vegetable-tanning is an extraordinary productive process, performed by the skilled hands of master tanners, based on the exact mix of vegetable tannins, on the good Tuscan water and on all the time necessary. It takes time and patience, and the skillful combination of technology and tradition.

A tannin is a substance contained in many different types of plants and can be concentrated in the bark or in the leaves, wood, roots or even fruits depending on the species. Chestnut tannin is extracted from the trunk of the chestnut tree and is particularly suitable to tan heavy leather and sole leather because it procures a compact yet flexible material with a good water resistance.

Minimize the impact on environment:

Invest on construction of centralized purification systems, organize specific industrial areas, recycle by-products and reuse waste water treatment sludge.

The production process:

1. Hide reception
2. Hide storage
3. Cutting and/or trimming
4. Soaking
5. liming—de-hairing
6. Fleshing and pelt slitting, if necessary
7. Scudding (de-limming and bating)

Chrome tanning, the most common tanning method in the world.

Today, 80-90% of leathers in the world are tanned by chrome tanning.

Chrome tanning uses a solution of chemicals, acids and salts (including chromium sulphate) to tan the hide. It’s a very quick process, taking about a day to produce a piece of tanned leather. First hide are limed to remove hair and then are “pickled” by being left in the acid salt mixture, before being placed in the chromium sulphate. All hides then come out looking light blue (known as “wet blue”).

In 2008, about 24 million tonnes of chromium was produced. About 2% of it has been used for the production of chromium sales, such as chromium sulphate, for the making of leather tanning materials but also for the production of dyestuffs and plastics. Worldwide approximately 480,000 tons of chromium tannins are produced per year.

The most important chrome deposits are found in South Africa accounting for 33% of production, while India and Kazakhstan provided 20% and 17% respectively. Brazil, Finland, Oman, Russia, and Turkey together contributed a further 21%, while some 12 smaller producer countries brought the balance of 9%.

Main advantages of chrome tanning

1. Quick and easy to produce, usually only taking up to a day
2. Water can roll off the surface easily with appropriate retanning and finishing processes
3. Soft and supple to the touch
4. It is possible to obtain leather with a stable color
5. It is cheaper to buy than vegetable tanned leather, which means it is also easier to find
6. It has a high degree of thermal resistance

Disadvantages of chrome tanning

1. Chrome tanning is very bad for the environment.
2. It’s produced with little craftsmanship and very often mass produced
3. It doesn’t wear well with time
4. Chrome tanning often smells of chemicals
5. It doesn’t appear (neither is it) very natural
6. Lacks of charm and warmth

Faux and Future Leather

“Fake leather” are also called: Synthetic leather, pleather, patent leather, Poromeric imitation leather, PVC, faux leather.

VS

3d printed leather

and

Grow your own leather

Reference:

http://www.nothing-to-hide.org/LeatherFacts/Meat_industry:_by-product_recycled/Summary

http://3dprint.com/930/biotech-firm-looking-to-begin-production-of-3d-printed-leather-and-eventually-meat-in-brooklyn/

http://www.tca.uwa.edu.au/vl/vl.html

http://www.decomag.co.uk/content/buy-or-not-buy-leather-tough-decision

http://www.adafruit.com/blog/2013/05/02/fascinating-and-frightening-ways-3d-bioprinting-is-the-next-big-thing-in-medicine-and-science-3dthursday/

http://beforeitsnews.com/green-living/2013/10/faux-leather-3d-printing-leather-without-cruelty-2449618.html

http://ecopolproject.blogspot.com/2013/11/is-3d-printing-and-green-eco-leather.html

http://www.nanalyze.com/2013/07/organovo-co-founder-resigns-from-board/

http://www.theguardian.com/lifeandstyle/2008/aug/27/ethicalfashion.leather