“Tokuno Blue” represents one of the techniques Momotaro Jeans is most proud of—an exceptionally deep, highly saturated indigo that stands apart even within the denim industry.
In fact, when Momotaro Jeans was founded over twenty years ago, they had already mastered and implemented this ultra-deep rope-dyeing method. Over time, the fabric develops strong contrast and layered fading—an unmistakable signature that denim enthusiasts have long admired and talked about.
Tokuno Blue isn’t a completely new idea, but rather a further refinement of that original technique—pushing the depth and saturation of indigo even further.
Why does Tokuno Blue look so deep?
What makes Tokuno Blue truly distinctive comes down to how Momotaro Jeans adjusts the yarn density to minimize the visibility of the white weft yarn.
Denim is a type of twill fabric. During weaving, the shuttle moves back and forth across the loom, interlacing the warp and weft yarns.
Simply put, the warp yarns are the indigo-dyed (blue) part you see on the surface, while the weft yarns remain white.
To achieve a purer, darker indigo appearance, Momotaro Jeans packs the yarns more tightly—adjusting from the standard 64 yarns per inch to 67 yarns per inch.
With less white weft showing through, the surface reads as a richer, more continuous indigo—this is the look that defines Tokuno Blue.
The dyeing behind Tokuno Blue
Now that we’ve covered the fabric structure, let’s talk about dyeing. Momotaro Jeans’ indigo stands out for a reason—there are many details behind how it’s achieved.
To create Tokuno Blue, fabric construction alone isn’t enough. The most important part is still the dyeing itself.
Darker isn’t always better.
Most indigo denim is dyed using rope-dyeing, and in Japan, truly experienced facilities capable of consistent rope-dyeing are relatively rare. Typically, repeating the dye dips around 8–12 times is considered a standard range. Over-dyeing, however, can make the dye bind too aggressively to the yarn, resulting in a slightly sticky feel and less nuanced fading.
What Momotaro does well isn’t just the final color—it’s the control. By repeating the rope-dyeing process around 29–30 times, they build the indigo gradually, layer by layer, producing a striking visual depth while keeping the hand feel clean.
The dye recipe itself is a closely guarded secret—developed together with the craftspeople at Japan’s legendary denim mill Kaihara. Through rope-dyeing, the yarn is dipped into indigo, then exposed to air to oxidize.
When indigo first attaches to the yarn, it appears yellowish-brown. Once the yarn is lifted out of the dye bath and meets the air, oxidation occurs—and it gradually turns into the blue we recognize.
In the hands of skilled craftspeople, the yarn repeatedly moves between the indigo bath and open air—over and over again.
This is one of the main reasons Momotaro’s indigo looks so deep: the process is repeated around 29–30 times, taking far more time than a typical dyeing routine.
After dyeing, the yarn is rinsed and set, then dried to finish. Only then is the Tokuno Blue warp yarn complete.
Next, it’s sent to vintage shuttle looms at the mill, woven together with the weft yarn, and turned into the Tokuno Blue denim Momotaro is known for.
In the image, you can see that even after so many dye dips, the core of the yarn remains white.
That white core is exactly what creates beautiful, high-contrast fading over time—and it’s one of the biggest reasons raw denim is so compelling.
Tokuno Blue may take longer to show its full character compared to standard denim, but once it does, it becomes something uniquely yours—shaped by craftsmanship, time, and wear.
