A photographic journey through the tanneries that produce NEGRONI’s leather.This time, we visit the production site of Sanyo Co., Ltd., a tannery with over a century of history, based in Himeji, Hyogo Prefecture.
Where leather is born
Himeji, Hyogo Prefecture. The lime that once supported the white walls of Himeji Castle, along with the region’s pure water sources, laid the foundation for a thriving leather industry. Today, this area accounts for approximately 70% of all cowhide produced in Japan, making it one of the country’s foremost leather-producing regions.
Nestled in this historic area is Sanyo Co., Ltd., a long-established tannery founded in 1911. Before visiting, let’s take a brief look at the area’s rich history in leathercraft. Himeji has long been known for producing “Himeji Shironameshi-gawa”, a white-tanned leather crafted using natural ingredients like lime, salt, and rapeseed oil. Records of this technique appear in the Harima Fudoki—a local chronicle compiled in the 8th century—as well as in the Engishiki, a legal document from the Heian period. The techniques have been passed down through generations for over a thousand years.
A blend of natural conditions and human ingenuity led to the area’s leather-making legacy: the river’s flow, a dry climate, access to salt and raw hides, and proximity to urban centres. During the Muromachi period, leather was used for saddlery and armour, and by the mid-Edo period, its use had expanded into everyday items such as document cases and bags. The people of Himeji lived with leather as part of daily life. To this day, the tradition continues quietly in this region.
In the Meiji era, as Japan underwent rapid modernisation, leather-making techniques also shifted to Western methods. Strong, supple leather was in high demand for military use, and tanning methods such as vegetable tanning and chrome tanning were introduced throughout the country. In Himeji, Russian-style vegetable tanning arrived in 1905 (Meiji 38), and the Himeji Leather Plant was established as a facility to put the method into practice. With the later addition of chrome tanning, the local leather industry quickly modernised, and the area grew to become a leading leather production hub in Japan.
Sanyo Co., Ltd., our destination for this visit, is a prestigious tannery that has its roots in the original Himeji Leather Plant. We visited on a crisp, sunny day in late February.
The morning air in Himeji was chilly, and a stillness hung over the factory grounds.
Sanyo starts work early—at 6:30am. By the time we arrived, operations were already underway. Steam rose from the back of the facility, escaping slowly from the drums and hot water used in the tanning process. You could sense the heat and humidity seeping into the cool morning air.
Guiding us through the facility were Mr. Shiota, Executive Director in charge of rawhide procurement and quality control, and Mr. Tamotsu, the Director and Head of Manufacturing. Accompanying them was Mr. Matsumoto, who has been responsible for Negroni’s leather coordination since the brand’s founding. Together, we toured the tannery, observing the machinery, the processes, and the people at work—learning step by step how the leather used in our products comes to life.
Traditional Vegetable Pit Tanning
Sanyo is one of the few tanneries in Japan that still operates a traditional “vegetable tanning pit” system. This pit-based process, which dates back to the Meiji era, remains virtually unchanged to this day. Around 30 pits are filled with tannin solutions extracted from plants such as mimosa and chestnut, into which the hides are soaked in succession for weeks or even months. Skilled tanners oversee this delicate process, adjusting the tannin concentrations according to daily variations in temperature and humidity. The steps may appear simple, but they are vital to the final leather quality. It’s these precise, consistent efforts that create leather with enduring strength.
Preparing the Base
After the pit tanning is complete, the leather is slowly dried and conditioned to create a base for dyeing. At this stage, it hasn’t yet been coloured. This untreated leather, called shitaji-nume, takes on a soft beige hue rich with vegetable tannins, exuding a quiet yet powerful presence.
The dried leather may still have slight unevenness. To correct this, it is carefully ironed at high temperatures, smoothing the surface and ensuring a consistent texture. This crucial step, carried out by expert hands judging each piece individually, has a major impact on the final dyed finish.
Sanyo also supports modern tanning techniques, such as chrome tanning and combination tanning. Chrome-tanned leather, known as “wet blue”, takes on a distinctive pale blue tint. Unlike vegetable tanning, it offers superior softness and water resistance, allowing for more specific usage based on the material’s properties.
By preserving age-old techniques while meeting the demands of today’s products, Sanyo embodies the essence of thoughtful craftsmanship.
Layering Colour
Once prepared, the leather begins to absorb colour—a gradual process that enhances the material’s natural beauty.
Dyeing takes place in rotating “dye drums”. Vegetable-tanned leather is especially delicate; the density of the fibres and the surface texture cause variations in dye absorption. To ensure precision, Sanyo uses a small test drum called a shiken-taiko to assess how the leather takes the dye before beginning the full-scale process. Only after confirming colour depth, vibrancy, and texture is the leather moved to the main dyeing drum.
Chrome-tanned leather, by contrast, offers more uniformity and easier dye penetration, but still demands close attention. The temperature, pH levels, and even water hardness must be fine-tuned to allow the colour to set in the most natural way.
In both methods, the goal is to discover the colour that the leather wants to be. Rather than forcing it into a predetermined shade, the craftsman’s skill and the material’s unique character come together to create a singular, unrepeatable hue.
Once dyed, the leather is hung on elevated conveyors to dry. Bathed in natural light and air from above, the material gradually releases moisture. Knowing exactly when the drying is “just right” takes years of experience—even slight residual moisture can significantly affect later processing.
Each piece of dyed leather is now ready for the next stage, gradually taking shape into something beautiful. No two hides are exactly alike; every piece carries its own distinct character.
