Bamboo is typically harvested when it is 3-4 years old. The parts of the bamboo stalk that are used to make fabric are the cellulose fibres, which are extracted from the outer layer of the bamboo stalk.
Following the bamboo being harvested, the stems, or culms, can be processed in one of two ways, mechanical or chemical.
Breaking down the bamboo
Both methods start with chopping the stems into bamboo chips, just like the woodchip you’ll be familiar with.
Then these chips are processed differently in the two methods.
In comparison, they are soaked in strong chemicals to soften them in the chemical process.
After this soaking, both methods revert to being the same process.
This soaked pulp is rolled out and dried into sheets.
The sheets are ground up into raw fibres and then the fibres are spun into thread and then woven into fabric.
However, the fabric we end up with is very different depending on the soaking process.
The use of Chemicals in Bamboo processing.
With the chemical soaking, the end result is a rayon or viscose bamboo fabric.
The use of Chemicals in rayon bamboo processing is no less than in the other ways in which we get rayon and viscose. Although the initial growth of the bamboo may be sustainable, we would struggle to maintain its eco-friendly label once we involve the same, chemical-heavy processing.
2) The crushed bamboo cellulose is soaked in a solution of 15% to 20% sodium hydroxide at a temperature between 20 degrees Centigrade to 25 degrees Centigrade for one to three hours to form alkali cellulose;
3) The bamboo alkali cellulose is then pressed to remove any excess sodium hydroxide solution. The alkali cellulose is crushed by a grinder and left to dry for 24 hours;
4) Roughly a 1/3rd as much carbon disulfide is added to the bamboo alkali cellulose to sulfurize the compound causing it to gel. Carbon disulfide is a colorless liquid with an ether-like odor. Exposure can cause dizziness, poor sleep, headache, anxiety, anorexia, weight loss, and vision changes. It can harm the eyes, kidneys, blood, heart, liver, nerves, and skin. Workers may be harmed by carbon disulfide.
5) Any remaining carbon disulfide is removed by evaporation due to decompression and cellulose sodium xanthogenate is the result;
6) A dilute sodium hydroxide solution is added to the cellulose sodium xanthogenate dissolving it to create a viscose solution consisting of about 5% sodium hydroxide and 8% to 17% bamboo fibre cellulose.
7) The viscose bamboo cellulose is forced through spinneret nozzles into a large container of a diluted sulfuric acid solution which hardens the viscose bamboo cellulose sodium xanthogenate and re-converts it to cellulose bamboo fibre threads which are spun into bamboo fibre yarns to be woven into reconstructed and regenerated bamboo fabric.
Regulatory bodies have been very strict about how manufacturers label their clothing and fabrics because rayon and viscose can be produced from many organic sources such as Beech, Pine and Eucluptus.
Manufacturers should say whether their fabric is 100% bamboo viscose or rayon, or if it has a mix of fibres it should state this on the label and packaging.
What’s the difference between Lyocell and Bamboo Linen?
Other bamboo fabrics, such as Lyocell and bamboo linen, have been mechanically ground, pulped with natural enzymes and spun, and are therefore more eco-friendly and a better choice when switching to bamboo.
Now we know to check the labels and look for lyocell or bamboo linen, what’s the difference between the two?
Lyocell is a soft, semi-synthetic fabric which uses a closed-loop manufacturing process making it more eco-friendly than its distance cousin, Rayon.
It looks and feels soft and will be marketed as bamboo fabric, sometimes mixed with lycra or spandex in order to maintain its shape.
Bamboo linen has the feel of linen. A little rougher around the edges but this is due to the 100% natural, mechanical, chemical-free way it has been processed.
Which bamboo fabric is better?
Making good, ethical choices means doing a little bit of homework and reading the labels.
Many manufacturers will attempt to greenwash their products making them out to be more ecologically sustainable than they are however if we look beyond the misguided marketing we can see that even bamboo rayon or bamboo viscose is a better choice than non-bamboo rayon.
Sustainable bamboo fabric is a great choice for eco-conscious consumers. Bamboo is a renewable resource that grows quickly, with some species growing up to 1 meter per day.
It does not require the use of fertilizers or pesticides, and it can be harvested without damaging the environment.
Bamboo fabric is also biodegradable and recyclable, making it a great choice for those looking for sustainable materials. Additionally, bamboo fabric is naturally anti-microbial and odor resistant, making it a great choice for those with sensitive skin or allergies.
Finally, bamboo fabric is incredibly soft and breathable, making it a top choice for clothing and is used in home decor more than you’d think.
5 home decor items which use bamboo fabric;
1. Bamboo Couch
2. Bamboo Ottoman
3. Bamboo Throw Pillows
4. Bamboo Curtains
5. Bamboo Cushions
We don’t have to be perfect, we just have to try to be a little bit better.