One day of dyeing, one week of "lye removal"
In reality, a single day is sufficient to dye one garment. (Excluding cases where the process is split over several days to achieve an extremely dark color.)
So, what are we doing between the dyeing and the finished product? Most of the remaining time is spent on a process called "post-treatment."
Our indigo dyeing is done using a traditional method called "natural lye fermentation," which uses no chemicals whatsoever. As the name suggests, we use "lye" (aku) extracted from hardwood ash to prepare the dye vat. After dyeing, thoroughly washing away this lye—which is unique to indigo—that has settled into the fabric is crucial for the final color.
Depending on the weather, this post-treatment (lye removal) alone takes about one week.
The etymology of the word "akanukeru"
After dyeing, we wash the fabric, dry it in the sun, and soak it in hot water. Repeating this process three to four times causes the brownish lye to leach out into the water. This indicates that the lye is being removed from the fabric.
There is a Japanese term, "akanukeru." It refers to someone becoming sophisticated and losing their rustic appearance, and one theory suggests that this term originates from the process of "removing the lye" (aku-nuki) in indigo dyeing.
The more it is washed, the more the impurities—the lye—are removed; the dullness fades, and the indigo color becomes vivid and clear. People of the past used the term "akanukeru" to describe this beautiful transformation.
Your own personal blue, grown through washing
In our workshop, we perform as much lye removal as possible before delivering the garment to you. However, over time, a little more lye will continue to leach out from deep within the fabric. You will need to continue removing this over several years of daily life.
Sometimes we hear from people who say they haven't washed their indigo products for years, fearing color transfer or fading, but with indigo, the opposite is true. Please wear it daily and do not hesitate to wash it. Soaking it in lukewarm water is ideal, but if that is difficult, regular washing is perfectly fine.
As you repeat the process of washing, the lye will naturally be fully removed, and the indigo color will become even more clear and vivid.
As the dullness fades and it matures into a clear blue, that brilliant indigo color stands as the ultimate testament to the owner’s relationship with the garment and their long-term companionship in daily life. Please wear it often, wash it, and nurture an indigo shade that only you could create.