In part two of the denim school, I sat down with Johan who explained the most essential things regarding jeans. Jeans is as I mentioned in part 1 a complete science, and this are the most essential parts of it.

Indigo has been used to colour different types of textiles for at least 4000 years, and is the most used dye in the world. It’s a natural colour agent that can be found in several plants, all around the world. It has been regarded as somewhat magical, and was believed to being healthy for the skin as well as scaring of snakes and mosquitoes.

Another aspect of indigo is that the colour surrounds the fibres and actually makes the fabric stronger. A unique feature of indigo is that it does not bond strongly to the fibres. As such, repeated wear and washing causes the dye to lift from the surface of the fibres while leaving the underlining fibres largely intact.

There are three major weaving techniques (we use all three). Right-hand was the first one used by Levis. The grain lines runs from the top right-hand corner of the fabric to the bottom left, and is the most commonly used. It makes the denim (and jeans) quite stiff and hard. The jeans becomes hard wearing but can crack over time, but it also has the benefit that it gets nice patina.

Left-hand is a technique developed by Lee and gives the denim a softer character, but isn’t as durable. In opposite to Right-Hand, the grain lines run from the top left-hand corner towards the bottom right. It also stretches more, and therefore gives a looser fit.

The last type is called Broken twill and was invented by a man called John Neill Walker for Wrangler in 1964. It’s different in that way that its diagonal twill line change direction. Except the unique surface texture, this weave also prevented the legs from twisting, which was a common occurrence at the time.

In the early 30´s a man called Sanford Cluett invented a technique to pre shrink jeans (raw denim usually shrinks 3-4 inches). This technique is still used on basically all jeans today. One of the most common used fadings is whiskers, and is developed either by hand or laser (or natural tear). Another used technique is to use enzymes. The enzymes eats up the indigo leaving the fabric with a washed look, without tearing on the fabric. Some jeans are also given a dirty look by a technique called tinting, which means that you dye the jeans with a base colour.

Selvage is the narrow tightly woven band on either edge of the denim fabric, which prevents the edge of the fabric from unravelling. At first the legendary Cone Mills used different colours of the thread, in order to identify the particular fabrics used by their manufacturers. Levis began with an all white strip and later on had a single red stripe along both selvages, Lee’s had a blue or green strip and Wrangler had a yellow. In the late seventies manufacturers began to shift from 27”-30” shuttle looms to much larger 60”+ modern versions, which were more cost efficient. However it also meant an end too much of the selvage, since the new machines did not have the recognizable selvage on either side.

A common advice when buying raw denim is to wear them as long as you possibly can, the denim gets the most natural look by doing so (something you might already know). Instead of washing them you can put them in the freezer or hang them out to air them. Another piece of advice when buying jeans is that when standing barefoot the jeans should barely touch the floor. Jeans usually shrink one cm. This is a matter of taste of course.