Cork is a versatile material used for over 5000 years in insulation, footwear, and other domestic uses. This article covers everything you need to know about cork fabric and explores its sustainability.
What is cork fabric?
Cork fabric is a type of plant leather; we also call it cork leather. The fabric comes from a specific tree called the cork oak tree. Its entire production process is environmentally friendly, so, like cactus leather, it's one of the most sustainable vegan leather options available today.
You can get cork fabrics in all colors and prints. However, the unique natural pattern we know cork for will remain visible on one side. On the other side of most cork fabric, you'll find cotton, linen, flax, PU, polyester, or some other textile used as interfacing or backing. This backing provides support and flexibility; otherwise, the material would fall apart.
Cork fabric has a wide variety of applications. Manufacturers use it to make purses, bags, belts, table coasters, yoga mats, shoes, garments, wallpapers, upholstery, and flooring. You can use the fabric for virtually anything you can make with leather.
If you enjoy DIY projects, you'll be pleased to know that this cork is relatively easy to work with. It takes to dye easily and presents no more challenges than conventional leather. You can make cool crafts with a sewing machine, glue, and basic DIY tools.
Although cork fabric is reasonably new on the market, it's easy to get for craft projects. You can purchase the sustainable fabric on Amazon, Etsy, or from branded stores like Sallie and MB Cork. You can also support a sustainable leather store nearby by shopping locally.
History of cork fabric
As far back as 3000 B.C., people in Persia, Egypt, China, and Babylon used cork to seal containers and as fishing floaters. Cork entered the footwear industry around 1600 to 1100 B.C. in ancient Greece, where they used it as soles for sandals.
Perhaps the most popular use of cork has been as a bottle stopper for wine bottles. The practice started in the 17th Century with the Benedictine monk Dom Pérignon. Other areas of cork application include medicine and insulation1. Cork has come a long way, and cork fabric is the latest in its line of applications.
Cork production contributes immensely to the local economies where it is grown. Portugal’s production amounts to almost half of the world's cork, and its cork industry employs over 8,000 people and is worth over €1 trillion in exports.
What is cork fabric made of?
Cork is a unique plant material sourced from the bark of the Cork oak (Quercus suber L.). The cork oak is a slow-growing perennial found in specific regions of China, Southern France, North Africa, Italy, Spain, and Portugal.
Cork harvesters peel off the oak trees' outside layer of the trunk. The first harvest happens when the tree is about 25 years old. Subsequent shavings occur every 9 to 12 years, enough time for the bark to attain the perfect level of thickness before harvesting.
Harvesting cork does not harm the tree in any way as long as it is done correctly. The durable tree goes on living and regrows the lost bark. Now, that's amazing, considering they remove over 50% of the bark at once; other trees would die off.
It is a common belief that the cork oak is the only tree to survive after losing massive amounts of its bark. Cork oaks can live for more than 200 years.
Manufacturers often grade cork fabrics according to the quality of raw cork used. The highest-grade materials have fewer holes (bugs), while they make lower-grade ones with post-industrial waste. However, all fabric grades are sustainable options; the right one for you depends on the intended use.
How is cork fabric made?
The process of making cork fabric is simple. However, it requires a lot of patience. That's because there is a lot of waiting involved, right from when the tree is planted to the time of harvest and after.
Let's take a look at the manufacturing process
The first step in cork fabric production is harvesting the bark of the cork oak tree. Growers harvest the bark mostly from the tree's trunk and partly from its main branches.
Cork harvesting is usually done by hand. A skilled worker uses an axe and is careful not to damage the inner layer of the tree. They do the debarking process in summer because it comes off easily when dry.
After the harvest, they keep the rather large bark slabs stacked in storage for about 6 to 9 months. The storage area is usually a shaded but open-airy space.
This storage flattens out the bark slabs' naturally rounded shape and enhances their texture. They may steam the cork on stainless steel panels during this time to help straighten it.
After the texturing, the next step is to boil the cork shavings in clean water for about a day. Some producers may use an autoclave for this process.
The boiling kills any fungus and bacteria that may have thrived on the bark during growth and texturing. It also decreases the density and renders the fabric more elastic.
Once the boiling process is through, they leave the cork to dry in a controlled environment. The timeframe for this second drying varies from manufacturer to manufacturer. Some say two weeks, and others let it dry for a few months.
The goal of drying it a second time is to stabilize the humidity so that further processing is possible.
Making the sheets
The last stage involves removing the outermost layer of the bark and then cutting and gluing it to make long planks. They pass the long planks through machines that press them into a thin cork sheet.
Eco-friendly manufacturers don't discard the tiny cork pieces unsuitable for making long planks. They ground them up and make sheets out of them, too (a bit like chipboard).
Then, they attach the thin cork sheets to a thin layer of fabric support backing. We call them backings, and manufacturers have options from any of several layers, including cotton, linen, hemp, polyester, and PU. Of course, the most sustainable backing fabrics are organic and not plastic-based. Less sustainable backings result in a less sustainable end product.
Qualities of cork fabric
Cork fabric isn't just valued for its plant origins. The fabric is resistant to deterioration and ages well. It can be just as durable as the finest leather. In fact, it may even be stronger.
In addition to its softness and near odorlessness, some qualities endear folks to cork fabric.
Cork is so lightweight that it can float on water. Half the weight of the material is air trapped in its cells.
So you can carry cork wallets, large bags, and other accessories around without worrying about weight. More space and less weight is a convenience this fabric offers.
Cork cells have spaces in them that fill with air. That makes it possible to compress the cork and allow it to recover after compression. This results in a bounciness, allowing the cork to behave like pads.
Being compressible makes the fabric more durable because it is not easily crushed. Also, it gives rise to extensive possibilities for application, especially in areas where we need padded textiles.
Cork's high concentration of suberin and honeycomb cell structure gives it high elasticity. Its elasticity makes it flexible and highly resistant to shock and pressure.
Cork fabric wallets, bags, and other items can stretch reasonably without damage. You don't have to work about your items going out of shape because of a little stretch.
There is a waxy substance in the cork that we call suberin. This substance coats the cork's cells and makes it resistant to water. That's why cork makes such good bottle stoppers.
Low permeability plays a significant role in making the fabric more durable than animal leather.
This fabric is resistant to stain within reason, of course, because it dyes easily. The stain-resistant quality is important to folks who use cork fabric because it naturally comes in light tan shades.
If food, oil, dust, and other stains get on your cork products, you can just wipe them off.
Cork burns slowly, without flames or toxic gases. It is naturally fire-resistant, which is why it's so useful as a fire-retardant material in buildings.
You may not necessarily require fire-resistant bags, belts, or wallets. But accidents happen, and while being close to the fire can irreparably damage plastic vegan leather, cork leather will be fine. Of course, it is always best to play it safe, so we don't recommend testing this out.
Cork's hypoallergenic quality doesn't come from any chemical in the material. Rather, it is a direct result of its ability to repel dust.
Dust mites are a common cause of allergies in the household. They are microscopic organisms that thrive in the dust. But since cork fabric does not attract dust, they can't breed in it; that way, cork may help prevent allergic reactions.
Another important quality of cork fabric is that it doesn't show scratches easily. The cell structure and surface texture enable it to withstand scratches from friction, impact, or abrasion.
That means you don't have to worry too much about scuffing.
Is cork fabric sustainable?
Cork has many strong sustainability points in its favor. If we could put a price on it, the value of environmental services for cork oak forests would be €100 per hectare each year.
Let's look at some things that make cork leather so sustainable.
Renewable raw material
Cork comes from a renewable plant resource, the cork oak. And the tree doesn't even have to be cut down. They just remove the bark, which regenerates within a decade, then remove it again.
The tree suffers zero damage if the debarking is done carefully. Furthermore, cork oaks can live for over 200 years. So, there's no need to disrupt the soil by replanting for a long time.
A common problem with highly demanded plant materials is monoculture plantations that damage native ecosystems. This is not the case with cork oaks.
A cork oak grows in a savannah-like forest called Montado. Those Montados are one of the 36 biodiversity sanctuaries in the world. They have trees, shrubs, and grasses that allow many different native plants and animals to thrive.
Cork oak forests contain 135 plant species per square meter. It is home to endangered animals such as the Imperial eagle, Bonelli eagle, and Iberian lynx.
Reduced Carbon emissions
Planting trees to absorb carbon dioxide is one of the top approaches to fighting climate change. However, when they cut down these trees, usually for commercial purposes, much of the carbon is let back into the atmosphere.
Cork oak trees act as carbon sinks, and these trees are never cut, so they live for centuries, keeping carbon locked in. Some of that carbon is lost during debarking, but a cork oak tree takes in extra CO2 as it regrows its shaved bark.
Cork oak forests worldwide sequester more than 14 million tons of CO2 yearly. In the fight against global warming, that is a significant contribution. Equally important is how the forests improve the air quality of the community.
A cork tree is grown without pesticides. That's because, in the past, the use of chlorophenols to control pests contaminated cork stoppers. The contamination led to fungi growth that tainted the taste of wine. The issue nearly drove the industry into extinction.
Further along the production line, cork requires no additives, tanning, or chemical finishes. You cannot say the same for animal leather, which requires chemical additives and tanning to arrive at the end product. However, cork leather dyed with inorganic chemicals no longer stacks up quite well.
We always advocate recycling over trashing, but sometimes, you just have to throw some things away. It is excellent for the environment when the things we throw away can decompose and turn into soil-enriching organic matter.
Cork is slow to break down, but it will eventually biodegrade. Those with synthetic fiber backing will not decay completely because plastic is not biodegradable. Choose an all-natural cork fabric for 100% biodegradability.
Cork is recyclable, so we can repeatedly turn it into new products. Although, curbside recycling isn't usually available for non-mainstream materials like cork fabric. You'll need to find an interested recycling company to take them.
Also, the cork chips that break off during extraction, processing, or production stages are pretty useful. Manufacturers can grind them up and use them for various cork products.
When isn't cork fabric sustainable?
Cork seems perfect, but its sustainability may need to be improved in some instances. Below are some of those situations.
Humans manage cork forests. Sustainability is compromised if people give up the traditional non-disruptive management style for a more exploitative one.
Mismanagement can come from eliminating native plants to grow more trees or harvesting in a way that intentionally damages the trees.
If they line your cork handbag or shoe with PU or other synthetic textiles, it isn't 100% biodegradable. Also, the environmental concerns about plastic would still apply.
Toxic dyes, fabric protection spray, and other toxic treatments make cork less sustainable.
Transportation and use
They harvest cork by hand; there are no machines spewing fumes at this stage in its production.
However, the impact of cork fabric does not end after production. How they ship it to customers and how customers use and dispose of it matters, too.
Caring for cork fabric
Compared to animal leather, cork leather is much easier to maintain. The material is resistant to dust, water, and stains. If you have cork fabric wallets, totes, etc., the care tips below are useful to ensure they last long.
Gentle hand cleansing
You don't need to machine wash cork items. Just wipe the surface with a soft cloth soaked in soapy water. You can immerse it in warm water for a gentle wash as well.
The best way to get the moisture out of your cork fabric items is to air dry them thoroughly. Don't put them in a dryer; avoid long hours of direct sunlight.
Some cork fabric products will come with specific maintenance instructions. It's best to follow them to the letter in such instances.
Cork, a versatile and impermeable material turned into fabric, is quite sustainable; it doesn't require felling trees or a lot of chemical input. It is better vegan leather than plastic leather and more animal-friendly than animal leather. However, you must ensure that your cork fabric products are sourced responsibly.
Duarte, A. P., & Bordado, J. C. (2015). Cork – A Renewable Raw Material: Forecast of Industrial Potential and Development Priorities. Frontiers in Materials, 2, 116294.