It’s soft and breathable, absorbent and durable; it’s no wonder that cotton is the world’s favourite natural fibre. It’s used in everything from clothing to cushions and available in varieties from denim to damask.
Today, China and India are home to the bulk of the world’s cotton-growing industry. Meanwhile, the most commonly grown cotton variety is Gossypium hirsutum. Better known as upland cotton, it’s favoured for its high yield and ease of cultivation.
The question is, how is cotton manufactured? We’re following the thread of facts to learn how cotton is made and how cotton is processed from seed to factory and beyond.
Cotton: A Short History
Before asking ‘how is cotton made’, it’s worth noting just how long it has been in use. Thanks to some fascinating archaeological finds, this can be traced back to at least the 5th millennium BC. This was the estimated age of the oldest known cotton fabric, which was discovered in Peru. Other early civilizations in Mexico, Sudan, Egypt, India, China, and Pakistan are also thought to have been growing and using cotton, as early as 3000 BC.
Cotton wouldn’t reach Europe until the 16th century. However, once it did, it would eventually come to transform British commerce. This was neatly summed up by historian Eric Hobsbawm, who said, “Whoever says Industrial Revolution says cotton.” With this rich history in mind, let’s find out how cotton is produced in factories today.
How Cotton Is Made
The following is a general step-by-step breakdown of how cotton is made, from cultivation and harvest. Then we examine how cotton is processed including cotton ginning and quality control.
Native to tropical and subtropical regions, cotton is grown in more than 80 countries around the world. The world’s main producers of cotton are India, China, the US and Brazil. Cotton is usually planted in the spring. It grows in a boll, or protective case, around its seeds. The fabric we know as cotton is a product of the fibres surrounding these seeds. It typically takes around five months for the cotton to be ready for harvest. At this point, the boll is an orb of fluff. It looks a bit like a cross between a dandelion and candy floss.
Harvesting is either done by hand or by a harvesting machine known as a cotton picker. Cotton pickers extract the seed fibres from the bolls, leaving the plant behind. The picked cotton is then formed into a large block called a module and transported to the processing plant or ‘cotton gin’.
In terms of how cotton is processed, the initial process once at the plant is known as cotton ginning. Any large debris within the cotton would have been removed at the farm, but once at the gin, it undergoes a more thorough mechanical cleaning, removing twigs, leaves, burrs and sticks. Next, the cotton is dried to make further processing easier. Any moisture is evaporated using hot air, in a machine known as a hot box. A series of machines then use a mix of screens, saws and centrifugal force to remove any remaining debris.
Sourcing the Lint
The cotton seed is piped to the gin stands. These machines use an array of rotating circular saws to separate the seed from the fluff or ‘lint’. The saw teeth are designed to grab the lint, which is drawn into a flue, taking it to the packing station. The seeds, which are too large to squeeze into the same gap, are left behind. However, they are not discarded. Instead they might be sold as cattle feed or milled into cooking oil.
As for the cotton lint, it is pressed into bales using a tramper machine. For this, the lint is fed into a bale-shaped box up to a weight of 500 pounds, at which point it is pressed into shape. It is then securely tie-wrapped.
In the US and several other cotton manufacturing countries, the cotton trade is highly regulated. As part of this, cotton is allotted a grade based on its colour, cleanliness and general quality. Thus, a machine with gripper arms takes samples from every bale before it’s packed in plastic and labelled with an individual ID number. The samples are given the corresponding ID numbers, allowing for them to be used in the grading process.
How Cotton is Produced
Now you’ve learnt how cotton is produced in factories. So, whether you’re wearing it, sitting on it or have it hanging in fluffy form in your bathroom, you’ve cottoned on to the answer to ‘how is cotton manufactured’. There’s no pulling the cotton wool over your eyes.