JSR: The Ex-Rubber Maker Whose Photoresist Is in a Third of the World's Chips

As we saw in Japan Makes ~90% of the World's Photoresist, Japanese companies control most semiconductor materials. If Shin-Etsu Chemical supplies the substrate — the wafer — JSR supplies the light-sensitive coating that goes on top of it. For how these roles fit into the broader industry, our map of the six roles of semiconductor companies (in Japanese) adds useful context.

What kind of company is JSR Corporation?

JSR Corporation is a Japanese materials maker best known as one of the world's leading suppliers of photoresist, a material indispensable to semiconductor manufacturing. It was founded in 1957 as Japan Synthetic Rubber Co., a state-backed company created to domesticate synthetic rubber production, and grew on rubber for automobile tires. It renamed itself JSR in 1997 and, building on the polymer technology honed in synthetic rubber, progressively shifted its center of gravity to semiconductor materials.

For the fiscal year ended March 2025 (April 2024 to March 2025), consolidated revenue was 405.0 billion yen, with about 7,645 employees and an overseas revenue ratio of 70.2%. R&D spending was 34.2 billion yen — roughly 8% of revenue — making JSR a decidedly research-driven company (JSR Corporation).

What defines JSR is its bold pivot from rubber to advanced materials. Its name appears nowhere on a finished smartphone or AI server, but its products are deeply embedded in the lithography chemicals used to make the chips inside them.

How is JSR's revenue structured?

JSR's business consists of three main segments. The pillar is the Digital Solutions segment, centered on semiconductor materials; alongside it sit the Life Sciences segment (diagnostics and drug-discovery support) and the Plastics segment (ABS resins and other synthetic resins). Digital Solutions covers electronic materials such as photoresist as well as display materials for LCD and OLED panels.

The most recent audited segment revenue (fiscal year ended March 2024) breaks down as follows.

(Source: JSR Corporation)

By revenue, Digital Solutions and Life Sciences are roughly comparable, but semiconductor materials are the profit engine. In the fiscal year ended March 2025, companywide operating profit was negative 209.1 billion yen (reflecting Life Sciences impairments and acquisition-related amortization), while core operating profit excluding those items was 0.2 billion yen. Semiconductor materials earn steadily; losses in Life Sciences have been canceling them out (JSR Corporation).

Where does JSR's technological strength lie?

JSR's technological strength lies in photoresist — above all, its head start in EUV resist. Photoresist is a light-sensitive chemical coated onto the wafer whose properties change when exposed to light. A lithography machine projects the circuit pattern onto this film; after development, the circuit shape emerges. How fine a circuit can be printed depends directly on the resolving power of this chemical.

JSR applied the polymer-design expertise it built in synthetic rubber to the molecular design of resists. It holds high share in ArF immersion resist (a lithography method that fills the gap between lens and wafer with water to boost resolution) for leading-edge logic, and its resist is estimated to be used in roughly one-third of all semiconductors produced worldwide. Because even a minute defect or particle in the film ruins the circuit and drags down yield (the share of good chips), purity and reproducibility engineering form the core of its competitiveness.

In 2021 the company went further, acquiring US-based Inpria for approximately 514 million dollars. Inpria is the world leader in metal-oxide EUV resist — a chemistry fundamentally different from conventional organic resists that is considered capable of printing finer circuits at higher resolution. When leading-edge EUV lithography machines from ASML (in Japanese) print circuits, JSR's metal-oxide resist stands ready as a leading candidate for the light-sensitive layer.

What role does JSR play in the supply chain?

JSR sits upstream in the supply chain, supplying lithography-step consumables to foundries and IDMs (chipmakers that handle everything from design to manufacturing in-house). Making chips requires resist optimized for each circuit generation (node), coated onto and consumed with every single wafer. As long as production continues, resist keeps being ordered — the source of JSR's stable revenue.

This is where qualification carries enormous weight. Before adopting a new resist, chipmakers run prototypes and evaluations over long periods, tuning quality to their own volume production lines. Once a resist is designed in, switching to a rival product is anything but simple, and switching costs stay high.

The more advanced chips are produced for generative AI, the more lithography passes are run at leading-edge nodes — and the more resist is consumed. In other words, growth in AI server demand ripples all the way upstream to materials makers like JSR.

What do JSR's market position and competitive structure look like?

JSR is ranked at or near the global top in advanced-lithography photoresist chemicals, with research-firm tallies putting its share above 20% in 2024. Photoresist is an oligopoly in which five Japanese-linked players (JSR, Tokyo Ohka Kogyo, Shin-Etsu Chemical, Fujifilm, plus Dow- and Merck-affiliated suppliers) account for roughly 90% of the global market, and JSR is among the front-runners (Toyo Keizai Online).

A five-forces view of this market looks like this.

The biggest entry barriers are purity and qualification track record. Only a handful of companies worldwide can reliably supply resist at leading-edge-node requirements, and without years of quality qualification a supplier simply is not adopted. Because this is not a price-driven market, incumbent positions are hard to dislodge. For the broader strength of Japan's materials supply base, see Japan Makes ~90% of the World's Photoresist.

What are JSR's weaknesses and risks?

The biggest weakness is the struggling Life Sciences business. Centered on biopharmaceutical development and contract manufacturing, the segment has posted continued losses, and in the fiscal year ended March 2025 it booked large impairment charges. This dragged companywide operating profit down to negative 209.1 billion yen.

The semiconductor materials side is not immune to market cycles either. When foundries cut capital spending or chip inventories are being worked down, resist demand temporarily softens. In addition, earnings are highly concentrated in the single domain of semiconductor materials, leaving results heavily exposed to the single tailwind of AI demand.

On the governance side, JSR was taken private under the Japan Investment Corporation (JIC) in 2024, so parent-led restructuring will continue for the several years until any relisting. The business portfolio could shift substantially during that process, leaving residual uncertainty.

What are JSR's recent moves?

JSR is pursuing two things at once: concentrating on semiconductor materials and scaling up EUV resist. In April 2024, a tender offer by a JIC-affiliated acquisition vehicle succeeded, and JSR was delisted from the Tokyo Stock Exchange Prime Market that June. The deal was valued at roughly 900 billion yen, and JIC now effectively holds 100% of the private company. The aim is to step away from short-term earnings pressure and focus on long-term structural reform and leading-edge investment (DigiTimes).

In EUV resist, JSR is accelerating the commercialization of the metal-oxide resist that came with the 2021 Inpria acquisition. In 2024 it announced a new development site for metal-oxide resist in the Kanto area and a plant at JSR Micro Korea in Cheongju, South Korea, to handle final production. The Korean plant is slated to start up in 2026, securing quality assurance and capacity in step with adoption evaluations at major customers (JSR Corporation).

Meanwhile, the Life Sciences portfolio is being pared back — including the sale of the in-vitro diagnostics business to Tokuyama for approximately 82 billion yen — as the company reorganizes around semiconductor materials (JSR Corporation).

JSR rarely makes headlines. But the finer AI-era chips become, the more quietly indispensable the company that controls the light-sensitive material that prints their circuits.

Key takeaways

• JSR was founded in 1957 as Japan's state-backed synthetic rubber company and is now a materials giant whose photoresist is used in roughly one-third of the world's chips.
• Consolidated revenue for the fiscal year ended March 2025 was 405.0 billion yen; the Digital Solutions segment centered on semiconductor materials is the earnings pillar, alongside Life Sciences and Plastics.
• Its key strength is a head start in EUV resist, having acquired metal-oxide EUV resist technology through the 2021 purchase of Inpria.
• Customers are foundries and IDMs; because photoresist is a consumable where purity and qualification form the entry barrier, switching costs are high.
• Taken private by government-backed JIC in 2024. Key risks are market cyclicality, the struggling Life Sciences business, and concentration in a single materials domain.