Since ancient times, humans have treaded upon the skin of animals. This can be traced back to literally all major cultures and civilizations of the world.
Called as “Leder” in old English and Proto-German, it meant “tanned or otherwise dressed hide or skin of an animal”. In ancient Roman, Greek, Indian, Egyptian, and Mesopotamian civilizations as early as 3000 BC, the use of leather products for making shoes and gloves and drinking water bags are found.
The use of leather in the modern day has seen strong criticism on moral and environmental accounts. With 14% by volume and 70 times more potent than CO2, Methane (CH4) is effectively the highest contributor for climate change. Recent demands have come up for reducing leather consumption and replacing it with artificial leather made out of petroleum products and microorganisms.
Artificial leather has been in high demand since its emergence as a replacement for natural leather. The demand for the same has increased exponentially in the past few decades. The graph below shows the hike in artificial leather demand.
Figure 1 growth in demands of artificial leather
The synthetic leather market in Europe is expected to grow from US$ 5,914.40 million in 2021 to US$ 9,123.76 million by 2028; it is estimated to grow at a CAGR of 6.4% from 2021 to 2028.
The polyurethane segment led the Europe synthetic leather market, based on type, in 2020.
In Europe, currently, France, the UK, and Russia are the worst-impacted countries by the COVID-19 pandemic.
Multiple primary interviews have been conducted with industry participants and commentators to validate the data as well as to gain more analytical insights into the topic. Participants of this process include industry experts such as VPs, business development managers, market intelligence managers, and national sales managers—along with external consultants such as valuation experts, research analysts, and key opinion leaders—specializing in the Europe synthetic leather market. Alfatex Italia; BASF SE; Fujian Polytech Technology Corp., Ltd.; H.R.Polycoats Pvt. Ltd.; KURARAY CO., LTD.; Mayur Uniquoters Limited; Nan Ya Plastics; San Fang Chemical Industry Co., Ltd; and Teijin Limited are among the players operating in the market.
Replacement of artificial leather in what products
How are Artificial Leather made?
PU based
Polyurethane-based leather is created by coating a fabric such as polyester or cotton with a flexible polymer. It is then treated by various processes to make it look like real leather. Polyurethane-based leather is waterproof, lightweight, and soft. It does not fade or crack when exposed to sunlight.
This synthetic leather does not require additional plasticizers as it is made by using soft polymers. Polyurethane upholstery is the realistic imitation of genuine leather in terms of surface feel and overall appearance. There is a high demand for polyurethane-based leather in the automotive and clothing industries.
PVC based Faux Leather
PVC leather fabric is very similar to PU leather fabric. Instead of polyurethane, PVC leather fabric is made by combining polyvinylchloride with stabilizers (to protect), plasticizers (to soften), and lubricants (to make it flexible), and then applying them to a base material. Again, the base materials are typically polyester, cotton, nylon, or rayon.
PU and PVC Leather Difference
Structure: As previously explained, PU leather and PVC leather differ in their structures. PVC has more layers underneath its coating, making it tougher and more durable. PU, on the other hand, has less layers, making it more pliable and flexible to work with. PU can even wrinkle and stain like natural leather would while PVC can stand more extreme wear and weather condition.
Breathability: Due to its foam layer underneath its surface coating and skin layer, PVC leather is much less breathable than PU. This gives PU leather the advantage when it comes to being the preferred material for wearable clothing items. However, since PU leather has more pores on its surface, this gives PU leather the risk of absorbing stains and other unwanted particles. This is why most upholstery uses PVC leather instead.
Suede
Suede is a word that originated in medieval France for the product called “gants de suede” which translates to “Gloves from Sweden”. The product was typically derived from sheep leather. The upper grain of which needs to be scrapped to expose the napped underside of the hide. Such appearance gives an extremely soft finish and touch especially when made with lighter and thinner hide such as sheep. Suede could be tanned and dyed and made into products for which conventional hide leather would be otherwise too stiff.
In a nutshell, suede leather is soft, delicate, pliable, brush-textured, napped, and are used in application where a lot of stiffness and strength is not required. They are excellent clothing materials for winter. Sheepskin is usually used for making suede leather.
Artificial suede
To resemble the original suede, recent times have come up with artificial variants of the same. The terms is so common that the word “suede” itself becomes confusing. It is now synonymous and more naturally understood as artificial leather. The following is the method of preparing artificial suede or widely known as MICROSUEDE.
Microsuede:
To put it plainly, Microsuede is a type of microfibers. To understand Microsuede, let’s first check what microfibers are. Fibres which are less than 1 den are categorised as microfibers. Microfibers are produced within a range of 0.3 to 1 dtex (approx. same den). Diameters of the same are 10 µm or less. Microfibres are produced using one of the following many technologies:
(den = no. of gram in 9000 meters)
Figure 6 Microfiber Suede (source google)
- Dissolved type – by dissolving the outer sheath fibre in a bi-component yarn
- Split type – by physically or chemically splitting the bi-co yarn into two.
- Direct spun type – directly extruding by melt spinning process.
- Other methods
- Super-drawing technique
- Sheath-core spinning method
- Flash spinning
Microsuede is a human-made polyester fabric, made up of millions of very fine microfibres. Microsuede is cheaper than genuine suede and is more resistant to wear and stains. It also comes in lots of different colors and can be printed in various patterns. [HAR21]
Figure 7 Artificial leather – Microsuede based on PU/Nylon mix used in mechanical gloves by Mallcom India Limited
Plant-based
Of the environmental concerns lately, the leather industry has also seen a paradigm shift. The demand of mushroom (mycelium) based leather have soared greatly. A company called Mylo has patented plant based leather using the mycelium species of mushroom.
Mycelium is the vegetative part of mushrooms which can grow on literally anything. From bread, to rotten vegetables to saw dust to fruitpulp. Mycelium forms a network of fibrils in the substrate to eventually form a single system of organism that lives off the substrate. Apart from Mylo which uses Mycelium for the cultivation of leather, another type of artificial leather called Muskin has been invented.
Figure 8 Mycelium fungus growth (source wikipedia)
The cultivation requires one to isolate a particular variant of fungi and transfer to inoculate the same into a fungal biomass using a substrate like bread or vegetables and saw dust. Post processes using glycerol is performed to increase the tenacity to a level closer to original leather.
Figure 9 Mycelium leather (course bloomberg)
The plant based leathers have been a much talked of topic in recent times however the mechanical properties remain a question. Plant based leather are nowhere in comparison with the animal leather in terms of mechanical strength. The cost of producing plant based leathers is however already at par with animal leather. The cost certainly is predicted to go down with increase in the production in mass. [ERK22]
Bibliography
- [ERK22] – E.R. Kanishka B.Wijayarathna et. al.
Fungal textile alternatives from bread waste with leather-like properties. https://doi.org/10.1016/j.resconrec.2021.106041
- [HAR21] – Harshani Wijendra, Sri Lanka Institute of Textile & Apparel Technology (SLITA)
Manufacturing Process of Microfibres: Methods, Materials and Treatments https://textilelearner.net/manufacturing-process-of-microfibres/
