What is leather? Summary of Leather Socks 2019

WHAT IS LEATHER?
SYNOPSIS
What is leather?
What is tanning?
1. Where is the skin made from?
2. Raw tanning process (Production processes)
3. Tanning methods
3.a Vegetable - Tanned Leather
3.b Leather by Chrome (Chrome - Tanned Leather)
3.c Leather with Aldehyd (Aldehyde - tanned leather)
3.d Alum Leather
3.e Tanned Leather (Brain Tanned Leathers)
3.f Rose tanned leather
3.g Synthetic - Tanned Leather
3.h Rawhide
3.j Formaldehyde Tanning
4. Types of skin layers - Grades
4.a Grade 1 - Grain Leather (Full-Grain leather)
4.b Grade 2 Leather (Top-grain Leather)
4.c Corrected Grain
4.d Leather Nubbuck (Nubbuck Leather)
4.e Split Leather
4.f Suede Leather
4.g Leather Bicast (Bicast Leather)
4.h Patent Leather
4.j Rolled Leather
5. From other animals (From other animals)
6. Environmentally favorable (Environmental impact)
6.a carbon footprint
6.b Water footprint
6.c Disposal (Disposal)
6.d Chemical waste disposal
7. Role of enzymes
8. Preservation and conditioning Preservation and conditioning
9. In modern culture (In modern culture)
10. Religious sensitivities
11. Alternatives (Alternatives)
12. Some additional information
12.a How many types of leather are on the market?
12.b Where can leather be purchased?
This is a question I received from many friends and customers when buying products at Thuy Bich.

So I rewrite this article to provide knowledge about leather or basic about What is not leather for You, readers, readers have a better view and understand more about leather in English is Leather

Leather is a durable and natural material made by animal skin. The most commonly used raw material is Cowhide. Used in small scale to modern mass production processes.

Leather is used to make many different items including: Leather jackets, leather goods, leather shoes, Footwear, car seats, clothing, bags, book covers, fashion accessories and furniture. .

History shows that leather-crafted products date back to 2200 BC.

WHAT IS A SKIN SKIN?
Tanning is understood as the process of treating leather of animals to produce leather (crocodile leather, cow leather), making the material more durable and much more difficult to decompose. In the past, tanning was treated by the traditional tanning method using tannoit, a plant polyphenol chemical compound that has the ability to bind sustainably to proteins and compounds. Other high molecular weight organic.

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The hides will be stretched onto frames and hung for several days in large tanks with increasing concentrations of tannin. During this process, the leather will become less absorbent and less susceptible to infections, mold attacks, the skin will be softer and be used in the manufacture of leather goods.

However, at the present time the use of manual tanning is no longer common. The introduction of mineral-based tanning technology (Chemical tanning) makes the job easier, increases the productivity, and the supply of leather for the market. After 1980, the use of pentachlorophenol and mercury-containing biocides and their derivatives was banned. The production of mineral tanning became more and more favored by the traditional manufacturing process. However, in some areas with a long tradition, people still use manual methods to retain the methods of handling ancient leather.

To learn more about the types of leather used in daily life, you can go to the article about basic types of leather.

In the article What is tanning, I have presented the similarities, distinctions, similarities and differences, in order to bring the most intuitive information to the reader.



1. WHERE IS LEATHER PRODUCED?
Until now leather products are still being produced manually. Because people still want to make products that have the quality of animal skin. From household furniture to products for daily life or accessories such as: Mens Leather Belt (Belt Leather), Purse, Bags, Backpacks with very high durability.

=https://thuybich.com/da-thuoc-la-gi/have existed for decades from one generation to the next in a family.

Da-thuoc-duoc-san-xuat-tu-dau
Leather is made into sheets
The skin is taken from any animal that humans once took meat. It sounds like something terrible, but the use of the skin is part of recycling to use this excess to create great products in life today.

Leather is a durable and flexible material formed through the tanning of animal skins such as cow, buffalo, goat, lamb, deer, crocodile, ostrich ...

Leather is produced by a variety of methods, from individual to industrial.

The use of leather is to create a variety of leather products including clothing, shoes, hats, wallets, belts, badges, book covers, parchment and upholstered furniture ...

Some of you ask yourself:

+ Is leather toxic?,?

- Properly handled leather will not affect the health of consumers.

+ Is leather need quarantine or not?

- Usually the tannery will check the sheet is taken so you can be assured.

Next we will come to the concept of Tanning, which is the preparation for more clarifications about the types of leather below.

san-product-tu-da-thuoc
Leather products
2. PRODUCTION PROCESSES PROCESS
Leather is produced from slaughtered animals such as: Cow, Buffalo, Goat, Sheep, Deer, Crocodile, Ostrich leather and this is done at tanneries or leather companies with The original purpose was because they didnt want to throw away the skin so they looked for ways to take advantage of it to reuse it.

The leather production process is divided into three stages as follows:

Preparatory stages - Preparatory stages
Tanning - Tanning
Crusting
Surface coating (Surface coating (This is the stage to help the skin become more perfect)
a. First, the leather will be cut in half by placing in a long wooden frame marked with a certain code. After that, the whole pieces will be cut in half to facilitate further operations. In the first stages, the sheets will be cut in half and the symbols will be split into groups.

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Each group will have about 100 plates to be put into the mixer to completely remove the coat on the surface layer, in addition to the process of adding water, Soda complex and Lime amount, this chemical group has The skin elimination effect is very effective and the finished product will be the skin completely clean the fur surface and prepare for the Tanning stage.

= We can summarize as follows: Marking - Soaking - Incubating - Liming - Staking - Cutting - Bleaching - Soaking

b. The Tanning stage will require quite a high level of skill for the workers to be skilled to remove layers of meat, fat and a solution to help the chemicals to be easily absorbed deeply and the skin. at the Tanning stage. At this point, many people will ask, What is leather?, And then there is What is tanning. I mentioned in the previous section. We do not confuse the strange process called Tanning and The durable material created in the Tanning process is Tanning 2.

Leather_tanning, _Fes

After tanning, the skin does not have the perfect characteristics such as the surface is not flexible, rough, absorbed with water, the moisture is still high. This stage will be processed skin after tanning to create the raw leather panels.

Tanned_leatherc. Carpentry is a process of drying and lubricating the skin that includes a lot of activities to soften and can include: splitting, shaving, dyeing, whitening and a number of other methods. The leather plates are put into the press to make the leather the required thickness, the rest of the leather will be recycled as rolled leather. During this process, the worker must constantly check the details to ensure the thinness is eligible, the error in this process is very easy for a company to take great responsibility for inadequate delivery. quality as well as customer request quality products.

d. Next, the skin is put back into the 2nd mixer with a mixture of vegetable leaves, sap and water, dyes will also be added to make the skin resistant to water. Processing time at this stage is also faster and also much softer than the first time. Fine powder will be coated on the skin surface shortly thereafter, to create a layer of skin sticking to the glass surface and of course this glass layer has been coated with a similar layer of powder. The skin will be put into the oven to dry.

Note: Always keep the temperature at a moderate level to avoid crooked, curly corners.

And after 4-6 hours, the skin will be easily removed and sprayed as desired and polished by machine. This process makes the skin brighter as well as more even in the surface layer. However, the machine must not be too strong or hard, which can easily tear the skin.

By now, we have realized that creating a pure leather is not easy at all, Every step requires meticulous, hardworking and whole-heartedly for the work of each worker. leather industry. The production process is so complicated, so here I continue to share with you the common types of leather, how to identify skin types, how to distinguish genuine and fake leather along with specific characteristics about it.

3. SKIN METHOD (TANNING METHODS)
3.A VEGETABLE - TANNED LEATHER
Vegetable tanning is a manual tanning method that uses sources of tannin found in nature such as bark, fruit and leaves in liquid or powder form.

With the toughness, brown color, with the exact shade depending on the mix of materials and the color of the skin.

The brown color originates from the appearance of non-dyed leather.
With its unstable nature in water, it tends to discolor and to soak and let dry, it will shrink and become harder.
In hot water, it shrinks vigorously and partially clogs, becoming rigid and brittle. Boiled leather is an example of this, in which the leather has been hardened by soaking in hot water or boiling in boiling wax or the like (Typical products are Armor, Binding Covers, Hard-Sole Shoes)
This is also the characteristic of oak leather, exploited in traditional shoe polish.

This is the oldest and most popular tanning method in the world. To tan a leather, it takes quite a long time from 20 to 60 days.

For centuries, Tuscany tannery masters have found valuable secrets to continue this traditional craftsmanship passionately, while being flexible when combining traditional and traditional recipes. Advanced technology to produce a perfect leather.

The tanning process is largely different in the way chemicals are used, combining a number of specific methods. Here are some popular types:

3.B LEATHER BY CHROME (CHROME - TANNED LEATHER)
vegetable-and-chrome-tanned-leather
Invented in 1958, processed using chromium sulfate or other chromium salts.

This method produces a green product due to chromium and also produces many other colors.

It takes about 1 day to complete, making this method popular, making it suitable for large-scale production. % of global supply. (Considered the most popular method in modern use).

The final product of this method is usually more supple than vegetable tanning and does not get discolored or severely deformed like using Vegetable - Tanned Leather.

However, because chromium is a heavy metal element, there are many environmental problems that concern the production process when it is impossible to control the amount of waste produced during tanning.

3.C LEATHER BY ALDEHYD (ALDEHYDE - TANNED LEATHER)
By using compounds glutaraldehyde or oxazolidine, also known as White Surf due to the light cream color.

This type of leather does not contain heavy metal components like chromium, often used in shoes for infants and cars.

Fornaldehyd has been used for tanning in the past. However, at the present time, this substance is being phased out due to the chemical composition endangering the production workers and the sensitivity of many people to Fornaldelhyd.

Chamois leather is a tanning form of Aldehyd that creates a porous and highly absorbent leather. Da Charnois is produced by using oxidized sea oil (traditional cod oil) to create aldehydes during production.

3.D LEATHER (ALUM LEATHER)
Alum skin is transformed by using aluminum salts mixed with many binders and protein sources, such as flour and egg yolks.

This type of skin is not really tanned, rather the process is called Tawing and the collected material will turn back to rough skin if it is soaked in water long enough to remove alum salts.

3.E LEATHER BY BRAIN TANNED LEATHERS
Made by the process that requires a lot of workers in the labor process of creating finished products. Use emulsified oils, usually animals such as deer, cattle and buffalo.

Featuring soft, easy to wash.

3.F ROSE TANNED LEATHER
3.G SYNTHETIC - TANNED LEATHER
3.H RAWHIDE
3.J FORMALDEHYDE TANNING
In another article I will clarify the remaining concepts. We only mention the widely used methods as well as the effectiveness in the tanning process.

4. TYPES OF LEATHER - GRADES
leather-101-leather-grades

This is the part where people will find it interesting and less boring. Because most of us have met a lot in life especially when we hold or see leather products.

And right now, try holding the nearest leather product by your side, take a closer look and find out if your skin type is one of the things I will list below.

If classified based on the layers of leather, real leather is classified into three types: Full-grain leather, Top-grain leather and Split / Bicast leather

4.A LEATHER GRADE 1 - FULL LEATHER (FULL-GRAIN LEATHER)
It is the top layer of the skin and retains its original state without any sanding, polishing, etc. This is the best quality skin, and only the cows are taken care of. in strict environment, clean hygiene can avoid scars from scabies, scrub a few hemp rope, cacti or insect bites ... to use leather as full Grain leather.

Full Grain vs Top GrainDa Full Grain retains intact skin particles, the top epidermis of the skin so very natural and durable. The skin surface still penetrates the pores, so Full Grain, if used in shoes, is very airy, especially in hot and humid weather. Full Grain used as a bag is very luxurious, when used will produce a natural patina layer that makes the product color of time, soft ball and very smooth.

So that layer 1 skin is considered the highest quality skin layer. Products made from genuine leather will usually be: Furniture, Shoes made from whole leather.

Whole skin will be finished with an Anilin soluble medicine. Russian leather is a form of whole skin.

Depending on how the skin is treated and dyed, Full Grain is divided into:

- Full Grain Aniline - Grade 1: Rustic leather, only dyed, not covered with 100% natural surface.

- Full Grain Semi-Aniline - Natural Grade 1 skin: A type of leather that penetrates and lightly coats the surface polymer to reduce dirt and water repellency, and still has natural permeability.

- Full Grain Protected Leather (Pigmented Leather) - Grade 1 protective leather: the skin has a surface covered with a thicker polymer layer, no more natural permeability but the advantage is anti-fouling and waterproofing.

Do you own a full Grain leather with a few small scars, some insect bites or marks? Dont assume its not perfect, in fact, for a lot of people, you own very valuable leather goods.

4.B LEATHER GRADE 2 (TOP-GRAIN LEATHER)
Top Grain Leather is the second quality leather after Full Grain, created when part of the top layer of leather is removed so it is quite durable.

Top Grain surface tea is repeated many times for a smooth, glossy surface coating and shaping the skin grain, grain ... according to the manufacturers intentions.

Top Grain leather does not produce a natural patina during use, so with Top Grain leather products, manufacturers often create a very smooth, smooth and soft artificial surface. like Full Grain skin on contact. Due to a top surface coating, Top Grain leather is more resistant to stains, impermeable as long as the surface coating remains intact. use.

This is also a good quality leather and is used very popular in fashion and household products.

4.C CORRECTED GRAIN
Grade 1 leather surface is Grade 1 of cow leather but the surface is treated rub, grinding to eliminate imperfections of skin pieces such as scars heal, scratches ... before covering a layer of surface shaped like Natural leather particles.

This type of leather is commonly used in high-end products. It is durable, uniformly colored and perfect. Because it is grade 1, when using leather, it still creates Patina (natural color) to create a class and luxury for leather products.

4.D DA NUBBUCK (NUBBUCK LEATHER)
Many people confuse Nubuck leather with Velvet or Suede.

Nubuck leather, also known as Buck leather, is genuine leather, abraded to create a smooth cotton surface, when touched very smoothly thanks to the tight structure of the skin layer.

When you gently stroke the surface of the nubuck with your finger, these fine hairs fall to one side, creating a more translucent color than usual.

It is this characteristic that many people confuse nubuck leather with velvet fabric.

When using a damp cloth to wipe the surface of the skin, the color of the leather is darkened, because the nubuck skin has been rubbed against the outer protective layer so the ability of the leather to absorb is very strong.

4.E LEATHER (SPLIT LEATHER)
Split leather is the type of leather made from the fiber of the rest of the skin after the leather used to make the top-grain skin has been separated.

During the split between the top-grain and split skin, the split skin can be split (thinner) into middle split and flesh split.

A very thick piece of leather like the middle split can split into many layers until it is too thin to split any more.

Split leather will then be artificially coated on the surface and embossed with leather grain (bycast leather). Split leather is also used to make suede.

The toughest suede panels are usually made from split split leather or from spilled skin (skin has been shaved to a standard thickness). Suede is usually rough on both sides.

Today, manufacturers will use different techniques to make suede leather from full-grain leather to increase product quality.

Depending on the purpose of use, people can turn the suede upside down to make different products (visible face is not grainy).

However, this is not considered a standard form of suede.

4.F LEATHER (SUADE LEATHER)
Suede, suede here is turned inside out, however suede for the product has separated a layer of outer surface, that is, both sides are inside and are processed to look not too rudimentary .

It looks quite similar to Nubuck leather, but looking closely will not be as smooth as Nubuck, and the durability is also much inferior, because it is the inner