As a crafter, I often spend time admiring various crafts. An extensive range of colors, textures, patterns, and feel makes every piece unique. To further my appreciation of the material I work with, I have been researching the tanning process to learn how each step impacts how leather is made.
How leather is made is the tanning process and steps used to turn raw animal hide into leather. These steps include cleaning, preserving, adding color, and protecting the material. Each tannery will have its own methods. When finished, this creates a natural, durable, and luxurious material.
Let’s explore how leather is made by following each step and its role in the final product.
What Is Making Leather?
Making leather is the process of taking raw animal hides, typically a byproduct of the meat industry, and turning them into useable and durable material. The hides undergo various tanning processes that clean, preserve, color, and protect the skin.
When the raw hides are soaked in tannins, they bond to the hide’s fibers, preventing the skin from decomposing and providing the material with longevity. If no other steps occur, saturating the skin with tannins is enough to turn it into leather.
Over time, however, different steps have been developed to process the leather further, including adding color, texture, and a finishing coat. While these steps are not necessary to produce leather, they are used in most hides, opening up the variety of leather to be used for different products.
What We’ll Explore
- Clearing up Myths & Misconceptions
- History of How Leather Is Made
- How Leather Is Made Overview Table
- Methods for Making Leather
- How Is Leather Made
- How High-Quality Leather Is Made
- How Faux Leather Is Made
- How Vegan leather Is Made
- Pros of How Leather Is Made
- Cons of How Leather is made
- How To Improve How Leather is Made
- My Personal Research Into How Leather Is Made
- Helpful How Leather Is Made Insights
- Key Takeaways
Clearing Up Myths & Misconceptions
Although many companies will use terms such as “vegan leather,” the material they are referring to is not leather. This is used to mislead customers into thinking their material is leather without using animals. However, leather, by definition, is an animal product, specifically their skin. If a material is made using plastic, fruits, or any other alternative, it cannot actually be leather.
This by no means discounts alternative materials, as many alternatives may still be high quality and have similar characteristics as real leather. Synthetic materials are a great option for some who value different qualities in their material. However, it is key for customers to identify this marketing term to help them better understand what they are purchasing and allow them to make an informed decision.
History of How Leather Is Made
Leather has been around since the Stone Age, but has used different methods to preserve the material. At the time when an animal was harvested, their brains and fatty organs were saved to be pooled. The animal hides were soaked in this mixture, stuffing the hide with oils and fats.
This would help preserve the leather but left a pungent smell. The alternative method of tanning is similar to what we still use today. Tree bark, plant leaves, and roots were forced into a hide by rubbing the material. This would become known as vegetable tanning, producing firmer leather.
While similar principles apply in the tanning process, we have developed ways to avoid unwanted characteristics. Urine, for example, was removed from most tanning processes, helping avoid unpleasant smells. Another area of improvement was the addition of the dying and finishing process. These two steps allow leather to be colored and add an additional layer of protection, helping prolong the life of an already strong material.
How Leather Is Made Overview Table
| Characteristic | Details |
| Hides Used | All leather must come from an animal’s skin. The hides used are often a byproduct from the meat industry but can be harvested in other ways. The quality of the skin helps shape the quality of the leather. |
| Tanning Method | Tanning is preserving the animal hide by preventing it from rotting and deteriorating. This is done with the use of tannins. Each company will have its own unique tanning mixture derived from various sources. |
| Dying | While leather can be left undyed, most will have color added. The dying process applies color to the leather through machines or by hand. |
| Finishing | Adding a finishing coat to the hide is an optional step when making leather. These coats act as a protective barrier preventing water and other damage forms. They are typically wax, acrylic, or oil-based. |
Methods for Making Leather
Where many variables go into how leather is made, the main changes occur depending on what leather is tanned with.
Vegetable Tanning
Vegetable tanning is a popular method as it is one of the most natural ways to preserve hides. It uses tree bark, plant roots, and leaves that slowly saturate the leather. This process can take up to a month but results in firm leather with many sought-after characteristics, such as the ability to patina, be burnished, and be carved.
Chromium Tanning
However, the most common leather available is chromium tanned leather. This process uses chromium sulfate to preserve the hide. The biggest benefits include production speed, a softer leather, and the ability to dye more easily. However, the chrome tanning process does not allow the leather to patina, carve, or burnish, losing some of its natural appeal.
Oil Tanning
Another common method for producing leather is through oil tanning. Oil tanned leather starts using the same process as chromium tanned but is then stuffed with various oils and hot waxes. This makes the hide more supple, but more importantly, it increases its durability and wear resistance. Since the hides are stuffed, they also become more water-resistant than most leathers. Similar to chrome tanned leather, oil tanned hides do not patina, carve, or burnish.
How Is Leather Made
Raw Materials
The raw materials from leather are often a byproduct of other industries. The biggest supplier of raw hides comes from the meat industry, where animals are used for their meat, leaving their skins to be used by the tanneries. However, this is not always the case, as some exotic animals are hunted solely for their hide — their skins may be highly sought after in the leather industry.
Tanning
The tanning process of leather is the most important step during manufacturing. The leather fibers become coated by using various tannins from different sources, including animal fat, chromium, tree bark, or leaves. Allowing them to resist degrading over time by preventing the hide from rotting. Each tanning method requires various amounts of time, up to a day, and adds different qualities to the leather depending on the methods used.
Re-tanning
As the name suggests, re-tanning is a process some leather manufacturers use to provide their products with various qualities. Since each tanning method provides the leather with different characteristics, treating it twice will expand on it. This can be done in any combination but is typically a mixture of vegetable and chrome tanning, improving the final physical performance of the leather by making it more wear-resistant while keeping the natural elements.
Drying
During the tanning process, drying is used multiple times. The first is after the leather has been washed and scraped. Water often saturates the hide during this cleaning process, and drying will allow more tannins to penetrate the leather.
Once the leather has been tanned, it is also stretched to dry. During this period, the stretching will help increase the size of the leather hide, while the drying will prepare the leather to receive dye in the next step of the manufacturing process.
Dying
Dying leather is the process of adding color to hides. This can be done in many ways, but the most common method is drum dying. This process places the finished hides in a vat filled with the color they will be. This helps fully saturate the leather with the color and may slightly soften it as it turns.
Another common way to dye leather is by passing it under a spray gun. This method covers the surface of the leather in dye but leaves the flesh side natural, providing a unique look and more targeted coloring.
Splitting
Splitting is removing the surface of the leather from the flesh side. This is typically done to make a hide thinner but may also be used to create suede. Splitting can be done before the tanning process to produce two separate leathers or after a hide has been processed to thin it for a consumer. When purchasing leather online, companies often offer splitting, allowing customers to receive any leather in any thickness they want.
Finishing
The final step in the leather-making process is finishing the leather. This step adds a protective layer to the surface of the leather. Layers can be made from wax, oils, or plastic. While not all leathers are finished, those will be slightly more durable and water-resistant.
How High-Quality Leather is Made
High-quality leather starts as a high-quality hide. These hides will have a dense fiber, with little to no blemishes on the surface. Typically, this requires the animal to be harvested at a young age. The tanning process also plays a significant role in the final product. Regardless of the method used, high-quality leather is thoroughly treated. This deep penetration of the tannins will provide a great platform for color and ensure the leather is well preserved.
After the leather has been dried, the dyeing process can take place. High-quality leathers often have a color added by hand, but it is not a requirement. In fact, some chromium tanned leathers often drum-dye to continue to soften the leather. The last step is to add a finishing coat. While plenty of high-quality leathers choose an aniline finish for a natural look, waxed or oil finishes are also popular.
This informative video by FeniceCareSystem provides an in-depth look at the tanning process, detailing the transformation of a hide step by step.
How Faux Leather Is Made
Unlike real leather, faux leather uses no animal hides in its manufacturing. Instead, the material attempts to achieve similar characteristics of leather using artificial materials. The general steps for making faux leather can include:
- Add a polyurethane base to a vat where flame retardant and UV protection chemicals can be mixed in.
- Liquid vinyl is then added to the mixture.
- Once thoroughly mixed, dyes can be added to give faux leather its color.
- This finish mixture is bonded to textured paper through heat and pressure, creating faux leather.
How Vegan Leather Is Made
While vegan leather is often be classified as faux leather, many types are available with different manufacturing processes. These include leather made from mushrooms, apples, cacti, and more. Vegan leather aims to produce a material that mimics leather qualities without animal skins while being more sustainable.
The current process for making vegan leather starts by harvesting the required base. Cactus, for example, will have its leaves cut and left to dry. Once the material is ready for further processing, it is ground into a fine powder. The powder is combined with a stabilizer, typically polyurethane, to help create a similar structure as real leather. At this point, the manufacturing process is the same as faux leather, adding dyes for color before adhering the mixture to paper-like material.
Pros of How Leather Is Made
The biggest pro regarding how leather is made is the final product. Leather is a high-quality material that offers durability, longevity, and versatility. It has been used in countless products for years with no signs of decreasing production. In addition, leather is biodegradable, making it a great choice for the environment.
Another benefit of how leather is made is using animal skin as a byproduct. While this may not be true for all leather hides, most leather we come across daily will have been salvaged from the meat industry. When animals are harvested, their skins are left over, often leading to additional waste.
Tanneries take these skins and transform them into the high-quality material we’ve come to know. Some tanneries take this a step further by pledging only to use byproduct skins, making their choice of skins more ethical.
When the raw hides are soaked in tannins, they bond to the fibers of the hide, preventing the skin from decomposing and providing the material with its longevity.
Cons of How Leather Is Made
The biggest con around leather making is the ethical concerns involved. While tanneries often use byproduct hides, this is not always the case, leading to some animals being hunted for their pelt. This has impacted some wildlife, resulting in farms to ensure populations don’t drop.
Similarly, the tanning process raises environmental concerns due to water usage. Tanneries use excessive amounts of water and often improperly dispose of the contaminated water generated. This leads to potentially tainted drinking water or farmlands when unregulated.
Yet another area of concern when making leather is the health risks to the people who produce it. While some tanneries have tried reducing work-related illnesses, most have not. The prolonged exposure to tanning chemicals and fumes commonly leads to chemical burns and chronic respiratory issues.
J Kanagaraj, K C Velappan, N K Chandra Babu, and S Sadulla, from the Central Leather Research Institute in Tamil Nadu, India, researched the effects of solid leather waste and proposed ways to prevent environmental damage. They found improper disposal creates harmful sludge, tainting the surrounding land, and suggested using leftover leather trimmings to create gelatin and glue to reduce the waste generated by a tannery.
How To Improve How Leather Is Made
The biggest improvement to how leather is made is advancements in water conservation and safer work practices. While this may not improve the overall quality of the leather produced, it has the much more important effect of changing the negative impacts of the industry. As it stands, many tanneries go unregulated, resulting in excessive water usage and improper disposal of tainted water.
This often leads to surrounding environments losing potential farming land and safe drinking water. To combat this, institutions around the work have placed more restrictions on how tanneries must handle their water needs, requiring locations to recycle a designated percentage and lower the amount of chromium remaining in the water to a safer level.
Working as a tanner is a demanding and dangerous career. The prolonged exposure to fumes often causes chronic health problems. To combat this, a well-regulated tannery will have proper protective equipment and limit the time exposed to harmful chemicals when possible.
Unfortunately, regulation is far from ideal globally, and ideally, the chemicals used should be reevaluated to protect workers. Vegetable tanned leather, for example, does not require harmful chemicals like chromium. With future discoveries possible, a big change in how leather is made would be finding a more friendly tanning method.
My Personal Research Into How Leather Is Made
While every step when making leather is important to produce the highest quality results, I decided to look at what makes the biggest impact in the process by researching the key areas and techniques used in the tanning process that separate good leather from great leather.
Hide Chosen
The first largest impact when making leather is the hide chosen for use. There is a large difference between high and low-quality hides that carry over throughout the tanning process. A high-quality hide will have a tighter grain, less blemishes, and may even be softer if using younger animals.
Low-quality hides may have a loose grain, many surface blemishes, or other undesirable traits. While the tanning process can work to make a lower-quality hide better, the limit of what is possible is raised by starting with the best hides.
Grain Type Used
While it can be argued that the grain type does not indicate the quality of a hide, it is clear that the potential it provides is higher. A full grain leather hide will not only be more durable and have a longer life, but it also contains an added visual appeal from a natural surface. This goes hand in hand with the hide chosen as lower quality hides will most likely require the surface to be removed to create nicer leather.
When discussing full grain leather, many automatically assume it will be vegetable tanned. However, this is not always the case. The benefits of full grain leather can also be seen in chrome tanned. One of the stand-out features that make Nappa leather so renowned is its use of full grain, highlighting the importance of keeping as much of the leather intact as possible when looking to produce high-quality leather.
Tanning Time
Many crafters have a preference between the tanning methods used to make leather. Vegetable tanned is often considered the best, producing the most natural finish. Despite this, the time the leather spends in the tanning mixture is often overlooked. A vegetable tanned leather that has been rushed will not be as high quality as another tannage type that has been thoroughly processed.
A great marker of this is how the leather looks from the inside. An off-color or bluish shade indicates that the leather was not fully saturated. This can lead to less durability and impact the way the dye penetrates the leather. High-quality leather will take up to a month to fully process, resulting in softer, more uniform leather.
Conclusion
Understanding what sets some leather apart is key to finding the best leather. While each step plays an important role in the final product, these are significant areas that can make or break a hide. Along with each tannerie’s proprietary tanning mixture, these steps help quality tanneries set themselves apart from their competition.
Helpful How Leather Is Made Insights
How is leather made step by step?
Leather begins as raw animal skin salted for preservation and shipped to a tannery. The leather is washed at the tannery, and the hair is scraped away. Hides are placed in vats containing various tannins, turning the raw skin into leather. The new leather is dyed and has a finishing coat added for protection.
Can leather be made without killing animals?
Unfortunately, real leather can’t be made without killing animals. Leather is the skin of an animal that has been processed into the material. However, many alternatives to leather on the market provide similar characteristics to real leather.
Is 100% leather made from animals?
Yes, all 100% leather will have come from an animal. Typically, this will be farm animals such as cows, sheep, or pigs, but it can be made from any animal. Exotic leathers, for example, use various reptile skins to create luxurious leather.
How is leather actually made?
As many people know, leather is made from raw animal skin. The step that transforms it from the skin into leather is the tanning process. This step uses tannins found in chemicals and naturally to prevent the skin from rotting — the tannins bond to the leather fibers, preventing bacteria from building up. After the skin has been treated with the tannins, it is now leather. Steps such as splitting, dyeing, milling, or finishing are all optional.
What is 100% leather made of?
Leather that is 100% will be made from the preserved skin of an animal. The percentage used when marketing this leather ensures customers that the product they purchase will not have any filler material added. Since there is no further information, there is no way to tell what animal the leather came from.
Key Takeaways
- Leather is one of the strongest and longest-lasting materials available.
- When animal skins soak in tannin mixtures, they are preserved and become leather.
- Most leather tanneries only use hides from the meat industry, making leather a byproduct.
In Closing
With leather being a cornerstone of our craft, learning how it is made provides invaluable information. It deepens the appreciation for the material and provides more details about what makes great leather, allowing crafters to choose better what leather will work for them.