Friendly Fashion: Mercerised cotton for long-life knitwear
- Beth Griffiths
- Apr 8, 2020
- 4 min read
I'm a big fan of mercerised cotton yarns for both knitting and crocheting. I've used mercerised cotton for knitwear for a long time: I incorporated them in many university projects (including my final graduate collection); I've used them to make knitwear pieces for myself; and now I'm using them for products on my online shop. Utilising mercerised cotton for fashion and textile products has a lot of benefits - including beneficial physical and aesthetic properties, and positive environmental implications.
Fibers, fabrics and their properties
Textiles are made from synthetic (plastic) fibers, cellulose (plant) fibers and animal fibers. Fibers are spun into yarns that are then woven or knitted into fabrics.
Natural fibres take time to grow harvest and process. Natural fibres (except silk) are short staple fibres. Their short length and naturally occurring properties can limit the uses and, therefore, the end products that they can be used for. Synthetic fibres are extruded as long filament fibres. These man-made fibres can contain whatever properties the manufacturer desires. The birth of fast-fashion meant that manufacturers needed to produce products fast enough to meet (and encourage) demand and cheaply enough to make a profit, which in turn meant that synthetic fibres started to be used more and more for our clothing.
Despite being cost-effective, time-effective and variable, synthetic fibres are detrimental to our planet. These fibres are created from crude-oil, a finite commodity that took millions of years to be created. They also tend to require a lot of heat, water and energy to produce, dye and press. At the end of its life, a synthetic product does not break-down easily or naturally, so (unless the product is recycled) it can be in landfill or an ocean for an incomprehensible number of years; fabrics such as polyester, nylon and acrylic take between 20 - 200 years to decompose.
Cotton, however, is a natural cellulose fiber, meaning that once the garments life-cycle is over it can decompose without leaving much of a trace. Wearing clothes made from natural fibres has a smaller impact on the environment during the "use" phase of its life-cycle too. This is due to natural fabrics not releasing plastic into the oceans and waterways. Every time a synthetic fabric is washed, tiny particles of plastic (micro-plastics) are washed from the item of clothing and drained away with the spent water. Furthermore, there tends to be a general fear of shrinking clothes made from natural fibres (particularly wool and cotton) resulting in people washing them on lower and gentler cycles... which can reduce energy usage!
As I mentioned before, fibres have properties which can restrict the products they are suitable to make.
Properties of cotton:
- Cool to wear, unless brushed
- Breathable
- Very comfortable, unless wet
- Highly absorbent, slow drying
- Strong, durable, abrasion resistant (good for workwear)
- Soft
- Good drape
- Creases badly, poor elasticity
- Washable, iron-able, may shrink
Cotton has many naturally occurring good qualities which make it a popular choice for textiles manufacture. These beneficial properties can be enhanced by applying finishes.
Mercerisation
Mercerisation is a chemical finishing treatment that can be applied to cellulose textile fibers. The process involves treating the cotton fibers with sodium hydroxide and then washing them clean. The treatment changes the structure of the fibers, resulting in a stronger, more durable fiber which improves the overall strength of the fabric. During the treatment process the fibres are shrunk which leads to dramatically less shrinkage in the final textile product.
Mercerisation has an impact on the aesthetic quality of cotton too. The process improves the dye up-taking properties of the fiber, meaning that a smaller amount of dye/weaker concentration of dye is needed to produce the same vividness of colour. The treatment also improves lustre, giving the cotton fibers a sheen and silk-like look. Mercerised cotton yarns often give a crisper, cleaner look to knitted and crocheted pieces; stitch patterns and colour changes often look more defined. [Some of this definition is also down to the how tightly yarns are spun: a yarn's twist will affect the fabrics weight and flexibility.]
This extra durability means that garments made from mercerised cotton will last longer and be more resistant to wear and tear. In regards to knitwear specifically, when mercerised yarns are knitted they hold shape better and for longer than "regular" cotton. Mercerised cotton is also less prone to pilling (forming fluff/balls of fibers on the surface of the fabric).
Buying durable, great quality garments that last reduces the amount an individual consumer buys (and throws away), reducing the person's environmental impact.
There is a dark side to cotton manufacture. Cotton requires a tremendous amount of water to grow and be processed. In mass production this water is often wasted, with harmful chemicals added to improve crop yields. Sourcing organic cotton is a way to reduce the negative effects of growing and harvesting cotton. "Organic cotton" is non-genetically modified, natural form of cotton - and the plants are grown without the use of synthetic fertilisers, pesticides or other chemicals.
There are also negatives to some chemical finishes (such as bleaching) that are added to fibers. The chemicals used can be damaging to ecosystems and need to be used and disposed of carefully. Closed loop manufacturing systems can reduce chemical and water waste contaminating waterways. Biotechnology is constantly evolving to try and reduce pollutants and environmental impact - Biostoning and Biopolishing are processes that utilise enzymes instead of chemicals to finish cellulose fibers.
Buying fashion and textile products responsibly and consciously is important - and buying ethically sourced products made from organic, mercerised cotton could be a good place to start!
If you've taken the time to read this, thank you! - Beth, thedaftduck x
References:
Cresswell, L., 2002.Textiles At The Cutting Edge. London: Forbes Publications, pp.18, 19, 240, 241, 293, 294, 295.
Science direct . c2020. Science Direct Cellulose Fiber. [Online]. [8 April 2020]. Available from: https://www.sciencedirect.com/topics/engineering/cellulose-fibre
You can check out my shop on nuMONDAY, where you'll find one-off pieces and made to order knits! And follow daftduck_ on instagram for work in progress updates, house-plant pics and vegetable growing!#shopsmall #stopthrowawayfashion
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