Why Are Most Jeans Blue?

Jeans styles may come and go, but a few features of the garment have remained constant throughout the decades. Whether they're skinny or ultra-baggy, most jeans have metal rivets, teeny pockets, and are made from blue denim. Blue may seem like an odd choice for a pair of pants that many people wear every day, but there's a good reason it became the standard.

According to Reader's Digest, blue has been the default color for denim since before Levi Strauss patented workers' trousers with rivets in 1873. When exposed to hot water, most dyes will permeate fabric and set in the fibers. This isn't the case with indigo dye. Indigo sticks to the outside of fibers, and in hot water, the dye gradually fades instead of seeping deeper into the material. As the indigo washes away, it brings minuscule amounts of thread with it.

This outcome would be undesirable with more delicate clothing items, but it works perfectly for denim. The material is so stiff to begin with that losing some fibers won't ruin it. Rather, a few hot washes give the fabric a softer, worn-in feel that many people cherish in their favorite pair of jeans. Because old blue jeans stay strong even as they get more comfortable, they were the favorite trousers of many laborers in the 19th century.

Most jeans are made with synthetic indigo dye today, and they're still built to get softer the longer you own them. A good wash can help break in sturdy denim, but you may want to wait to toss your brand-new pair in the washing machine. Jeans that have been worn for a few months before their first wash fade less evenly than jeans that are cleaned right away. This results in a fade pattern that's unique the wearer, which is something to consider if you care about giving your pants a distinct look.

[h/t Reader's Digest]

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