They’re so much of a part of our daily lives that we often fail to notice them. They’re versatile and have become a staple in all our wardrobes. How did they first come about though?
They were invented by Jacob W. Davis in partnership with Levi Strauss & Co. in 1871. Originally designed for cowboys and miners, jeans became popular in the 1950s among teenagers, especially members of the greaser subculture.
Traditionally, jeans were dyed to a blue color using natural indigo dye. Most denim is now dyed using synthetic indigo. Approximately 20 thousand tons of indigo are produced annually for this purpose, though only a few grams of the dye are required for each pair. For other colors of denim other dyes must be used. Currently, jeans are produced in any color that can be achieved with cotton.
Indigo dye is an organic compound with a distinctive blue color (see indigo). Historically, indigo was a natural dye extracted from plants, and this process was important economically because blue dyes were once rare. A large percentage of indigo dye produced today – several thousand tons each year – is synthetic. It is the blue often associated with blue jeans.
The primary use for indigo is as a dye for cotton yarn, which is mainly for the production of denim cloth for blue jeans. On average, a pair of blue jean trousers requires 3–12 g of indigo. Small amounts are used for dyeing wool and silk.
There are various dyeing and sizing processes, which can be classified into four categories.
- Continuous Indigo-Rope dyeing and sizing.
- Continuous Indigo dyeing and sizing.
- Indigo-back beam dyeing and sizing.
- Continuous dyeing and sizing.