Producer
Toyobo Co., Ltd.
Osaka-based Japanese diversified materials conglomerate (TSE: 3101). In 2022, spun out its specialty materials businesses into Toyobo MC Corporation (subsidiary), which produces: ZYLON® (PBO fiber — the world's sole commercial producer), IZANAS® (ultra-high-molecular-weight polyethylene fiber), TSUNOOGA® (high-strength polyethylene), HOLLOSEP® (cellulose triacetate hollow fiber membranes for dialysis and water treatment), VYLON® (polyester resins), BREATHAIR® (3D polyester cushioning). ZYLON PBO fiber (decomposition temperature 650°C, LOI 68) is produced at the Iwakuni Production Center in Iwakuni, Yamaguchi Prefecture. Full-scale ZYLON production began 1998. Toyobo MC is simultaneously the world's only PBO fiber producer AND the world's leading hemodialysis membrane maker — two life-critical medical and safety products from one Japanese specialty chemicals company. Toyobo paid $66M in 2018 to resolve False Claims Act allegations related to defective Zylon-containing bulletproof vests sold to US law enforcement (2003-2018 litigation).
3
Inputs supplied
2
Goods downstream
3
Facilities
1
Stories
What they make
3 inputs Toyobo Co., Ltd. supplies
Click an input to see every good that depends on it, every country that produces it, and every other company in the supply chain.
chemical
Sole supplierPBO / Zylon Fiber (Poly-p-phenylene benzobisoxazole) →
manufactured
Sole supplierCellulose Triacetate (CTA) Hollow Fiber Membrane →
manufactured
Cellulose Triacetate (CTA) Hollow Fiber Membrane →
Where it shows up
Goods downstream
Essential goods that depend on something Toyobo Co., Ltd. makes, pick one to see the full supply chain.
Where they make it
3 facilities
Toyobo Iwakuni Production Center →
JPmanufacturing
The original and still-primary CTA hollow fiber dialyzer membrane production facility globally; located in Iwakuni, Yamaguchi Prefecture, Japan. Operated since early 1980s. Prior to July 2024, was the ONLY commercial CTA membrane facility in the world. A second joint facility with Nipro opened at Odate, Akita in July 2024 — but both remain in Japan, preserving Japan-country-level concentration risk.
Toyobo MC PBO Fiber Plant →
JPOsaka Prefecture, Japan · manufacturing
Iwakuni Production Center, Iwakuni City, Yamaguchi Prefecture, Japan — Toyobo MC's primary specialty fiber and membrane production site. Houses the Iwakuni Environment and Fiber Plant (produces ZYLON PBO fiber, high-performance fibers), Iwakuni Membrane Plant (HOLLOSEP dialysis/RO membranes), and Iwakuni Resin and Chemical Plant. Full-scale ZYLON PBO production began 1998. World's only commercial-scale PBO fiber production facility. Any disruption at Iwakuni — earthquake (Yamaguchi Prefecture is in a seismically active region), industrial accident, business decision, or supply chain failure — eliminates 100% of premium-grade global PBO supply with no viable substitute. Toyobo MC does not publicize the precise plant address for competitive and security reasons. Also: adjacent to Teijin's Teijinconex meta-aramid plant (also in Iwakuni) — two critical single-source protective fiber types produced in the same city.
Toyobo Odate Akita CTA Hollow Fiber Plant (Joint with Nipro) →
JPAkita · processing
Second Toyobo CTA hollow fiber production site, opened July 2024. Joint plant within Nipro's Odate Factory (Hanukiyachi, Niida, Odate City, Akita Prefecture). Toyobo runs the front-end hollow fiber spinning (16,000 m² of 31,000 m² total); Nipro runs the back-end dialyzer assembly (15,000 m²). Built in response to 7%/year global dialysis patient growth. Partially mitigates the single-site Iwakuni chokepoint — but both sites remain in Japan.
What else they do
Business segments
The company's full revenue map, where this supply-chain role fits within their broader business.
HOLLOSEP® Cellulose Triacetate Hollow Fiber Membranes (Dialysis)
35%ZYLON® PBO Fiber (World's Sole Commercial Producer)
12%IZANAS® UHMWPE Fiber & High-Strength Polyethylene
15%Specialty Films, Resins & Other
38%
Stories from the supply chain
Editorial about Toyobo Co., Ltd.
Intelligence
What's known
Sourced claims about this company's role in supply chains, chokepoints, concentration, incidents, dual-use connections.
Did you know2024
Toyobo MC Corporation's ZYLON PBO fiber is simultaneously: (1) the suspension line material for SpaceX Crew Dragon Mk3 parachutes (protecting astronauts on re-entry); (2) a required wheel tether material in Formula One and IndyCar (preventing wheels from becoming projectiles in crashes); (3) a component of TenCate AGILITY firefighter turnout gear (protecting firefighters from thermal exposure); (4) used in racing yacht standing rigging (structural safety in ocean sailing); and (5) the material that — in a different application (bulletproof vests) — failed to protect two police officers in 2003, leading to one death, 98,000 vest recalls, and a $66M DOJ settlement. One Japanese fiber. One plant. Protecting astronauts, race car drivers, firefighters, and sailors — and having previously failed to protect police officers. All from the same production line in Iwakuni.
Wikipedia ↗Incident2018
In June 2003, two police officers were shot while wearing Zylon-containing bulletproof vests: Officer Tony Zeppetella (Oceanside, CA) was killed; Officer Ed Limbacher (Forest Hills, PA) was permanently injured. NIJ investigation revealed 58% of tested used Zylon vests failed to stop rated rounds. Toyobo had known about Zylon's degradation problem since at least 2001 — when it paid Second Chance Body Armor $1.421 million to continue selling Zylon vests despite internal knowledge of the problem. Toyobo also destroyed internal memos and published misleading degradation data. Result: 98,000 vests recalled, Second Chance went bankrupt, NIJ effectively decertified Zylon from body armor in 2005, and Toyobo paid $66 million in March 2018 to settle US False Claims Act allegations — 15 years after the scandal began. No criminal charges were filed.
U.S. Department of Justice ↗Note2021
In November 2021, Toyobo and Nipro announced a joint CTA dialyzer production plant at Nipro's Odate factory in Akita Prefecture, which started operating in July 2024. Toyobo runs the front-end hollow fiber spinning (16,000 m² of 31,000 m² total facility) while Nipro runs back-end dialyzer assembly. This represents the first time in 40+ years that CTA hollow fiber production has been expanded to a second facility. However, both facilities remain in Japan, so earthquake, tsunami, or supply chain risks at the Japan country level (e.g., acetic anhydride supply for acetylation) persist.
Toyobo Co., Ltd. ↗Capacity2023
Toyobo's HOLLOSEP cellulose triacetate (CTA) hollow fiber membrane is used in dialyzers manufactured by Nipro, Nikkiso, Kawasumi, B. Braun Avitum, and other dialyzer brands — making Toyobo an invisible backbone supplier for the majority of dialyzers produced by companies other than Fresenius (which uses its own Helixone polysulfone). Approximately 800 million hemodialysis sessions are performed globally per year; if each uses one dialyzer, 800 million CTA membranes must be produced annually. Toyobo's Iwakuni production center (Yamaguchi Prefecture) produces the vast majority of this supply. Unlike Fresenius, which is visible as the dialyzer brand, Toyobo is invisible to patients and clinicians — it is the fiber inside the device they depend on for survival, produced by a company most people associate with the fiber in their sportswear or mattress cushions.
Toyobo Co., Ltd. ↗Origin2023
Toyobo Co., Ltd. (Toyo Boseki Kabushiki-gaisha) was founded in 1882 in Osaka as a cotton spinning company — one of Japan's oldest textile manufacturers. Over 140 years, it evolved from cotton textiles through synthetic fibers to advanced specialty materials. The HOLLOSEP CTA hollow fiber membrane emerged from Toyobo's expertise in extruding very fine, controlled-pore-size cellulose fibers — a direct evolution from textile fiber manufacturing. ZYLON PBO fiber was developed in partnership with the US Air Force Materials Laboratory and licensed from DOW Chemical; Toyobo commercialized it as the world's only PBO fiber producer in 1998. Toyobo thus represents a complete transformation from cotton cloth to life-critical specialty materials — from commodity textile fiber to the artificial kidney membrane and the (once-promised) bulletproof wonder fiber.
Toyobo Co., Ltd. ↗