So I haven't done Textiles for about seven years and I found learning about the process of denim pretty interesting. I knew the process of cotton, grown and farmed as a plant then harvested to be spun into thread. The natural colour of cotton is of course off white but for denim, the thread is ring dyed as the dye cannot permeate fully.
To make Denim, which was originally 100% cotton but now has polyester and lycra added for stretch and softness, two threads of cotton are woven together- the Warp and the Weft. The warp which flows veritcally is dyed cotton whilst the Weft which is woven horizontally (weft = left) and this is undyed cotton. This is now the purest form of denim which we now add effects for fashion purposes. The company I worked with worked to 5% BCI Cotton which is ethically sourced.
RHT or Right Hand Twill is woven to the right and seen as more durable than LHT or Left Hand Twill which is woven in the opposite direction (and also the cause of the bottom of jeans leaning more to one side of the leg). Broken Twill is from left to right and back again and gives a herringbone style detail. Slub or Rain denim uses a mixture of fine and course yarns to create the effect of rain whilst this can also be woven on both Warp and Weft for Cross Hatch Denim.
The weights of denim mean different things and are weighed in oz per square yard or occasionally gsm (Grams per sq yard). 'Chambray' denim is very thin and only made with 5oz and often used for Childrenswear. Womenswear jeans are usually 9oz whilst Mens jeans are the heaviest at 12oz.
My favourite bit of denim knowledge was about shade blankets where for very large bulk orders of denim, the fabric will be dyed in batches and a cutting from each batch will be sewn together to create a shade blanket. After washing the final blanket, all the shades are inspected and graded while some shades are rejected for irregularities. I can't tell you how much I'd like to have one of these little denim patchwork blankets...
Once made into jeans, the wet and dry processing can begin. Because of the white cotton weft, it is easy to create effects on denim by scratching off the outer layer of dyed fabric. Distressed patches are created by cutting the raw denim threads carefully before washing. Whiskering, edge grinding, creasing and tagging are all ways of recreating how denim naturally creases with wear. These effects are made with sand paper free hand, over moulds or even sometimes resin is used which is later washed off. Sand blasting is another method that now uses PP spray after the findings that real sand blasting caused severe respiratory disease. Towel washing, acid washing with bleach or enzymes is common as well as stone wash which used real stone to batter the denim but can badly effect the washing drums.
Farming - Spinning - Dyeing - Weaving - Stitching -Wet/Dry Processing - Washing - Rivets, Buttons and Trims.
So now I know a hell of a lot more about denim and hopefully you do too. Thanks, Bee xxx
PS. I recommend 'A Denim Story: Inspiration from Bellbottoms to Boyfriends' by Emily Current and Merritt Elliott as its a lovely coffee table book.
PPS. Denim originated in Nîmes, France and in french it was called 'Fabriqué de Nîmes' later being shortened to just Denim.