COTTON

 

Jeans are made out of denim fabric which is primarily made with cotton. Cotton is a thirsty crop and requires water for growth. The majority of cotton is still being grown conventionally, relying on pesticides and chemicals. Alternative methods such as the Better Cotton Initiative (BCI), E3 Cotton and organic cotton, rely on less or no chemicals and reduced water intake during the growth of the cotton. After harvesting the raw cotton undergoes an array of cleaning and blending processes to produce a strong yarn during spinning. The cotton fabric for denim is created using two types of yarn. The lengthwise yarn is known as warp and the crosswise yarn is the weft. For denim fabric, only the warp yarn undergoes the dyeing process, and the weft yarn is left white.

 

Indigo

 

Indigo is the colourant which gives denim and jeans their distinctive and famous blue colour. Indigo occurs naturally, derived from plants in the genus Indigofera and has been used for dyeing for over 6000 years. Since the early 1900s synthetically created indigo largely replaced natural indigo. Indigo synthesis results in the formation of indigo powder or granules. Today, there are two main physical forms of indigo. Powder/granule indigo typically contains 88-96% of indigo molecules. Indigo can undergo further processing to form pre-reduced liquid indigo, which is achieved through the indigo reduction using hydrogen gas. Pre-reduced indigo typically has an indigo molecule concentration of 20-40%. This form of indigo allows the saving of 40-70% sodium hydrosulfite and 35-60% of caustic soda in the dyeing process, which contributes to better quality, industrial hygiene (health and safety), making the product more environmentally friendly and sustainable.

 

INDIGO DYEING

 

Indigo is a vat dye. Vat dyes are in pigment form which turns into water-soluble dyes by going through a chemical reduction using a reducing agent and caustic soda. The most common reducing agent is hydrosulphite. Only the reduced form of indigo can bind to the cotton fibre. The indigo dyeing process is unique, combining different dyeing techniques, exhaust and continuous dyeing. To ensure an effective dyeing process other chemicals, wetting, dispersing and complexing agents, and physical parameters, such as temperature and pressure, are considered in the dying process. Typically, the yarn is dyed in a continuous process, using a sequence of multiple dye baths, where the yarn is dipped into the dye bath and the indigo dye is being exhausted, followed by the exposure to air to undergo oxidation, which allows the indigo dye to be fixed as a pigment. The number of dye baths (dips) and the concentration of the chemicals in the dye baths determine the contrast and colour of the denim fabric. Utilising one to thirty dye baths is possible, but typically the warp yarn goes through an average of six to eight dyeing baths. Innovative dyeing equipment, like modified dye boxes, foam dyeing and spray dyeing, has emerged in recent years to reduce the energy, water and chemical consumption, improving the sustainability of the denim dyeing.

 

FABRIC PRODUCTION

 

Once the warp yarn has been dyed, the warp and weft yarn are woven together to produce denim fabric. Traditionally woven denim is made from 3x1 right hand twill (RHT) warp faced fabric. This refers to the number of weft threads per warp threads used. Denim that utilises a 3x1 weave are heavier. Lighter denim, will use a 2x1 weave. In addition to the influencing the weight of the fabric, the warp and weft count used influences numerous fabric properties, such as fabric tightness, cover, tensile and tear strength.

 

GARMENT PRODUCTION

 

Once the denim fabric has been produced, the garments will begin assembly. The fabric will be cut into the desired shape, which would usually be pre-determined by the design of the fashion designer. The pieces of denim are then sewn together to produce the garment.

 

GARMENT TREATMENT

 

The finished garment will undergo further treatment in the laundry, all which impact the appearance, aesthetics and the feeling of the denim garment. There are endless variations of treatments for denim, being achieved through chemical (i.e. bleaching, enzyme washing and acid washing), a mechanical treatment (i.e. stone washing, micro-sanding, laser), or a combination of both. Garment treatments create the individual look that denim and jeans are famous for, from raw to the distressed look. The finished garment is ready for labelling and can be distributed to retailers.

 

 

 

 

 

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GENERAL TERMS & CONDITIONS OF SALE

general terms & conditions of purchase