Culture, Trends & Stories

A Walkthrough Of How Denim Is Made

Most of us have at least one pair of jeans, but how much do you know about the processes that goes into making them? In this article, we attempt to break down the whole creation process — fibre to fabric.

February 8, 2021
Written by
Melinda Junata

We typically think of denim as coarse and uncomfortable but also simple, stylish. We can all probably name some big brands synonymous to jeans like Levi's, Lee, Wrangler, and so on. I always thought that these brands made every pair of their denim from scratch, but oh boy I was wrong. There's a whole lot more to make a pair than what most people would know.

After spending the past year working closely with product developers, designers, and denim enthusiasts, I want to invite others like me to learn more about denim's craftsmanship. I'm by no means a denim or textile expert. However, I do have access to experts and people who have been in the industry for generations. For 2021, I will be sharing this series 'On Denim' to breakdown the making, culture and history behind the indigo wardrobe staple.

Breaking It Down, From Fibre to Fabric

The biggest realisation for me was learning that brands like Levi's or Tommy Hilfiger do not fabricate denim. In other words, they do not weave their fabric. The denim supply chain is far more intricate than it appears. For starters, fashion brands source their denim fabric from denim mills which specialise in making denim fabric. Italy, Turkey, China, India, Pakistan and Vietnam are home to some of the most popular denim mills.

Step One: Getting The Cotton

Close-up Photo of Cotton Fibres

Denim's rigidity and sturdiness come from its primary material - cotton. Cotton is grown almost everywhere on earth, excluding Antarctica. Most denim mills get practically all of their cotton from the largest cotton growers in China, USA, India or Pakistan.

It takes about 140 days for the cotton seed to grow until the fruit, the fully ball called the cotton boll, is ready to be picked by a cotton picker machine or by hand.

Step Two: Turning Cotton Fibres Into Yarns

Ring Spinning Process

Cotton is a type of plant-based fibre and transforms it into a durable, long interlocked yarn; cotton fibres have to be spun or twisted in a spinning process. Before the spinning machine's invention in the Industrial Revolution, the spinning process was a manual process, done by hand. Currently, there are two types of yarn spinning techniques: ring spinning and open-ended spinning. Most manufacturers highly favour the latter one as it is faster and cheaper.

Step Three: Dyeing The Yarns

Gradients of Indigo Slasher Dyed Yarns

Dyeing is quite a unique process. There are two techniques to dyeing denim yarns: slasher and rope dyeing. Soaking in dye vats is a requisite to both methods as it allows indigo to penetrate deeper into the threads. In particular, indigo is where the fabric gets its deep blue colour. But sometimes it is dyed with sulphur to make black or coloured denim. What's unique about denim's dyeing process is its dependency on oxygen. When the cotton yarn comes out from its first dyeing vat, it is green in colour. But will turn blue over time as it dries up when exposed to oxygen. This part of the process is called oxidation.

Left: Yarn entering vat filled with indigo dyestuff
Right: Finished indigo dyed yarn

The denim dyeing process will only reach to the outer layer of the yarn and leave the core of the yarn white. As a result, the undyed yarn core will slowly reveal itself as you wear and wash your denim. This is the reason behind of denim fades. Note that wear fades is more evident in raw denim than pre-washed or industrially treated jeans.

Step Four: Weaving the Dyed Yarns

The typical denim weaving process involves two yarns woven together that lets the indigo-dyed threads interlace with un-dyed threads. The combination of dyed and un-dyed threads gives denim its characteristic of a blue front and a white back. Shuttle looms - an old-school weaving method is still in fashion today and is a characteristic of popular high-end selvedge denim. Nowadays, most denim mills use shuttle-less looms for weaving, allowing manufacturers to produce more fabrics in less time.

Selvedge Denim Weaving Process

The selvedge is popular because of its unwashed characteristics. Denim enthusiast prefer selvedge denim because of its commonly sold in raw indigo colour, which allow them give the denim unique fades by wearing them. People try to not wash their raw denim to keep the indigo last longer and create higher fade contrast.

Denim fabrics have to go through a rigorous quality assessment. When the material passes the evaluation, it is ready to be shipped to a garment factory that will transform the denim fabric into wearable jeans.

From Denim to Jeans

Denim Hunter, a leading denim blog, defined Jeans as trousers made from denim with common features such as five pockets, a fly at the front, five belt loops, and a yoke at the back.

Step Five: Designing the Jeans

Designers will always try to incorporate aspects of the end-users' lifestyle when designing a pair of jeans. By asking questions about the utility and demographic, designers can evaluate the technical specifications, draw out a technical sketch and specify the jeans treatment in a tech pack.

Step Six: Cutting Jeans Pattern & Sewing The Final Piece

Garment makers will trim the denim fabrics from the denim mills roughly into 20 pieces based on a design pattern that is part of the garment tech pack. They will also prepare the buttons, zippers, labels, and leather patches for sewing during this step.

Step Seven: Laundry Treatments

At this stage, you're probably wondering how was the light blue distressed pair you own looks the way that it does. Getting a pair of jeans to look distressed or washed out happens in the laundering, pre-wash or pre-distressing treatment phase. Some people do not have the patience to fade their jeans over several years. Hence, companies like Jeanologia or Tonello exist to create machines and laundry technologies to wash down the indigo colour to the designer's desire. Other than fading, some jeans are distressed by stone washing or laser to make it appear unmistakably vintage with wear and tear that generally comes with usage over time.

So Now You Know Something About Denim and Jeans

It broadly takes about seven steps to transform that fluffy little white ball into a timeless clothing piece that most people own for decades. In the next article, we will be covering a more in-depth exploration of buying denim and how can you be more conscious, while doing so. Share this article with your family, friends or colleagues to let them know how denim is made. Until next time!

This article is made possible thanks to Jorgen Sevild's guidance, Denim Hunter blog, and Blue Blooded: Denim Hunters and Jeans Culture book.