The word ‘synthetic’ shows up in a few different ways when talking about leather, and it may not always be clear exactly what it means. In fact, depending on the context, it’s entirely possible to see the materials, the tanning agents, or even the tanning process itself referred to as synthetic in some way. Synthetic tanned leather falls into the last group, but it isn’t just one specific leather tanning method; rather, it’s an entire category in its own right.
What is Synthetic Tanned Leather?
You might be tempted to guess that synthetic tanned leather is simply any leather that has been tanned using synthetic chemicals, like chrome tanned leather, for instance. Speaking literally, this would be correct. In practice, the meaning can be a little more convoluted. Most commonly, ‘synthetic tanned leather’ refers to all leathers tanned with synthetic chemicals except chrome tanned leather.
That might seem like an arbitrary place to draw the line, and in fact not everyone agrees with it. However, there’s a good reason for it. Synthetic tanning is unique because it’s almost always used as part of a combination tanning procedure; that is, alongside another tanning method. In particular, it’s frequently paired up with chrome tanning, so it can be useful to have a term to help distinguish them.
For some examples of what does fall under synthetic tanned leather, look to any leather that uses artificial tanning agents like acrylates, phenols, or most commonly, aldehydes.
Is Synthetic Tanned Leather the Same as Synthetic Leather?
Unfortunately, synthetic tanned leather is completely different from synthetic leather. This is especially inconvenient because they have similar properties and usages, so they’re often used interchangeably despite not actually being related. The silver lining is their names, which make for an easy way to remember which is which.
Synthetic tanned leather is a natural animal hide that has been tanned using synthetic tanning agents. On the other hand, synthetic ‘leather’ isn’t really leather at all. Other names for synthetic leather include vegan leather or faux leather. These names are actually all the same thing: an artificial material made from polyurethane or various plastics, designed to simulate the texture and qualities of an actual tanned hide.
What are the Main Types of Synthetic Tanned Leather?
All synthetic tanned leathers use synthetic tanning agents, which are usually abbreviated to ‘aromatic syntans’. Despite this similarity, there can be big differences depending on the particular tanning agents used.
The most popular syntans are aldehydes such as formaldehyde and glutaraldehyde. Unlike many other syntans, these can produce good quality leather without necessarily needing to be used in combination with another tanning method. They yield a soft and supple leather which is commonly used in industries like fashion, luxury goods, furniture, and automobile interiors.
The biggest drawback to aldehyde tanning would be the aldehydes themselves. Formaldehyde can be a dangerous chemical to work with, with some serious environmental effects as well. If you’re interested in learning more about aldehyde tanning, you can read all about it right here.
In general, synthetic tanned leather isn’t as sturdy as something like vegetable tanned leather, and it can have a uniform texture which may look artificial. For these reasons, syntans other than aldehydes are most often used as re-tanning agents, to help improve leathers that were tanned through other methods.
Many of these syntans fall under the class of phenolic monomers, or simply phenols. When applied to something like chrome tanned leather, phenols can enhance some of the most desirable properties of the leather; things like its texture, lustrousness, and flexibility.
However, phenols have the same problem as aldehydes. This varies depending on the specific chemical in question, but many of them are toxic enough to raise concerns about how safe they are to use.
What is Synthetic Tanned Leather Used For?
Synthetic tanned leather really has two distinct uses, depending on the particular tanning agents involved, and whether they’re used in conjunction with another tanning method.
The syntans most suited for individual use are members of the aldehyde family. As mentioned above, these appear very frequently in furniture: chairs and couches advertised as being made from leather are often made from aldehyde tanned leather or bonded leather.
Their most common role is almost certainly in automobile interiors. The specifics will differ from one manufacturer to another, but a large proportion of car seats and upholsteries are made from aldehyde tanned leather.
Other syntans such as phenols and acrylates find their main use in combination tanning, where they play the part of the re-tanning agent; after a hide has undergone the initial tanning procedure with chrome or vegetable tannins, the syntans essentially serve as a second layer, so to speak. Once it’s in this state, the leather is usually called “wet white”, because it is yet to be dried and dyed.
Is Synthetic Tanned Leather Good?
For something with as much variety as synthetic tanned leather, it’s hard to make a blanket statement covering all the different types. There are definitely some strong advantages to synthetic tanning. Aldehydes can occasionally be a reasonable compromise between chrome and vegetable tannins. Moreover, being able to improve a leather through re-tanning with syntans is a very convenient option to have available.
That said, you may have noticed a pattern when it comes to the flaws of syntans. In particular, they’re nearly all hazardous to some degree. This is determined by the specific chemicals being used, and it’s worth noting that the more popular syntans tend to be on the safer side. It’s still something to be mindful of, especially if sustainability is a concern.
Conclusion
Synthetic tanning is an innovative technique, with an impressive variety of uses. Its ability to enhance other types of leather via combination tanning is an enormous advantage, and aldehyde tanned leather in particular can be a very practical leather even by itself.
For now, the harmful chemicals involved can make this tanning method less desirable than it otherwise might be. However, syntans are being improved all the time, and it will be intriguing to see what kind of possibilities they create in the future.
