Mitsui Chemicals to Buy Chip Materials Maker JSR in $11.6 Billion Deal

Mitsui Chemicals is buying JSR, one of the world’s most important makers of the chemicals used to build advanced computer chips, in a deal worth 1.84 trillion yen — about $11.6 billion.

The Japanese chemicals group announced the deal on Monday, 9 November 2026. It is buying JSR from Japan Investment Corp (JIC), a state-backed fund, together with the Development Bank of Japan (DBJ). It is the largest deal ever in Japan’s chemicals sector, and one of the biggest ever in the semiconductor materials industry.

The deal matters far beyond Japan. Almost every advanced chip in the world — in smartphones, laptops, cars and the data centres that power artificial intelligence — depends on materials like the ones JSR makes. Bringing JSR together with Mitsui will create Japan’s largest supplier of the chemicals used in the most advanced chipmaking.

What the deal is

Under the agreement, Mitsui Chemicals and the Development Bank of Japan will acquire all of JSR’s shares from funds managed by JIC Capital. Mitsui’s board approved the deal on 9 November and signed a share purchase agreement the same day.

The headline price is 1.84 trillion yen ($11.6 billion). That figure is made up of an equity value of 1.3921 trillion yen, plus 447.9 billion yen of interest-bearing debt and other items. The final amount can still change slightly before the deal closes, because it is subject to adjustments at completion.

Mitsui will hold all of the voting rights in JSR once the deal is done. The Development Bank of Japan will invest 200 billion yen and will hold non-voting preferred shares — in plain terms, it is putting money in but will not control the company.

The deal is JSR’s second change of ownership in three years. JIC, a fund overseen by Japan’s finance ministry, took JSR private in 2024 for about 900 billion yen and removed it from the Tokyo Stock Exchange in June that year. JIC then ran an auction to find a buyer, and Mitsui won.

To put the size of the deal in context, it is more than double the $4.55 billion that Showa Denko paid for Hitachi Chemical in 2020 — until now one of the biggest deals in this part of the chip industry.

Why JSR matters: the chemicals that print chips

To understand why JSR is worth $11.6 billion, it helps to understand how a computer chip is made.

A chip starts as a thin disc of silicon called a wafer. To build the tiny circuits on that wafer, chipmakers use a process called lithography. They coat the wafer with a light-sensitive chemical called a photoresist, then shine light through a patterned mask to print the circuit design onto the wafer. The photoresist is the material that makes this printing possible.

JSR makes photoresists. According to Mitsui’s own investor presentation, JSR is the world’s second-largest maker of photoresists for advanced logic chips — the powerful processors used in phones, computers and AI systems. It is also the only company able to offer both leading types of photoresist for extreme ultraviolet (EUV) lithography.

EUV is the most advanced form of lithography in use today. It uses extremely short-wavelength light to print circuits so small they are measured in nanometres — billionths of a metre. Only a handful of companies in the world can supply the materials for it, and the machines that do the printing are made by the Dutch company ASML. JSR supplies the light-sensitive materials used with those machines.

JSR also owns Inpria, a United States company that develops metal-oxide resists for the next generation of EUV machines. Inpria has a joint development project with South Korea’s SK hynix for photoresists used in next-generation memory chips.

The business is growing fast. JSR’s semiconductor materials sales rose from 157.9 billion yen in the financial year 2024 to 196.0 billion yen in the financial year 2025, according to Mitsui’s presentation. For the financial year ended March 2026, JSR reported revenue of 440.7 billion yen and core operating profit of 62.3 billion yen, with 6,951 employees.

Why Mitsui wants JSR

Mitsui Chemicals is itself a major player in chip materials, but in a different corner of the process. It is the world’s top maker of EUV pellicles — ultra-thin membranes that protect the masks used in extreme ultraviolet lithography from dust and damage. A single speck of dust on a mask can ruin a whole batch of chips, so pellicles are essential.

Buying JSR would bring together the world’s leading pellicle maker with the world’s second-largest maker of advanced photoresists. The combined company would offer a wider range of the materials chipmakers need for both EUV and older deep ultraviolet lithography, including polishing materials, resin tapes and thick-film resists used in chip packaging.

Mitsui says the deal should bring it an additional 40 billion yen in annual profit. It is also part of a bigger, government-backed effort to consolidate Japan’s fragmented semiconductor materials industry. Japan already dominates many of the specialist materials used in chipmaking, but its companies are often small and split across many suppliers. The Japanese government has been pushing them to join forces so they can compete with larger rivals and keep supply chains secure.

That push is happening against the backdrop of the artificial intelligence boom. Demand for advanced chips is surging as companies build ever-larger data centres, and governments around the world are treating chip supply chains as a matter of national security. Japan wants to make sure the materials its chip industry depends on stay in strong, well-funded hands.

How Mitsui will pay for it — a very big bet

The most striking thing about this deal is its size compared with the buyer. Mitsui’s own market value is about 664.6 billion yen, according to LSEG data cited by Reuters. That is far smaller than the 1.84 trillion yen it is paying for JSR. In other words, Mitsui is buying a company worth nearly three times its own stock market value.

To fund the purchase, Mitsui plans to take out a bridge loan of 1.64 trillion yen from its main banks, and to sell new shares worth up to 150 billion yen. The money raised from selling shares will be used to pay back part of the loan. The Development Bank of Japan’s 200 billion yen investment also helps fund the deal.

Mitsui has said it plans to sell off JSR’s life sciences unit and other non-core businesses to raise money and sharpen the focus on chip materials. It aims to get its finances back into sound shape within three years of the deal.

That is a bold plan, and it carries real risk. Taking on a loan far larger than the company’s own value means Mitsui will be under pressure to make the deal work quickly. But it also shows how seriously Japan’s chemicals industry is taking the race to supply the world’s most advanced chipmakers.

What happens next

The deal is not done yet. It still needs competition and foreign-investment clearances in Japan and other countries, because JSR sells its materials to chipmakers around the world. Those reviews can take months.

Mitsui says it aims to complete the acquisition in the second half of the financial year ending March 2028 — that is, between October 2027 and March 2028. The company has warned that the timetable could change depending on how the regulatory reviews go.

If the deal closes as planned, the combined business will be Japan’s largest integrated supplier of advanced lithography chemicals. It will sit at the heart of the supply chain for the world’s most advanced chips, alongside a small group of Japanese, American and European materials companies.

What it means for the chip industry — and for ordinary people

For most people, this deal will never be visible. No one buys a photoresist or a pellicle in a shop. But the materials JSR and Mitsui make are inside every advanced chip, and advanced chips are inside almost everything: phones, laptops, cars, medical equipment, and the servers that run AI services.

When the supply of these materials is disrupted, the effects ripple outwards. During the global chip shortage a few years ago, car factories stopped, electronics prices rose and waiting times for new products stretched to months. Governments and companies have been working ever since to make chip supply chains stronger and less fragile.

Deals like this one are part of that effort. A bigger, better-funded JSR should be able to invest more in developing the next generation of photoresists, which chipmakers will need as they move to even smaller and more powerful chips. That matters for the pace at which new technology reaches consumers.

There is also a competitive angle. Japan’s materials companies face growing competition from rivals in South Korea, China and the United States. By combining two of its strongest players, Japan is betting that scale will help its companies stay ahead in a technology that underpins the entire digital economy.

Why this matters

This is not just a big number on a stock exchange announcement. It is a sign of how the global chip industry is changing. The materials that make advanced chips possible are becoming as strategically important as the chips themselves, and the companies that control them are becoming more valuable — and more contested — than ever.

Mitsui is paying a huge price, and taking on a huge loan, to own one of those companies. If the bet pays off, Japan will have a national champion in chip materials to match its ambitions in semiconductors. If it does not, Mitsui will be left carrying a very large debt. Either way, the deal will shape who supplies the chemicals behind the world’s most advanced chips for years to come.

Frequently asked questions

What is JSR?

JSR is a Japanese company that makes photoresists and other advanced materials used to manufacture semiconductors. Photoresists are light-sensitive chemicals that let chipmakers print circuit patterns onto silicon wafers. JSR is the world’s second-largest maker of photoresists for advanced logic chips.

How much is Mitsui Chemicals paying for JSR?

The deal is worth 1.84 trillion yen, about $11.6 billion. That includes an equity value of 1.3921 trillion yen plus 447.9 billion yen of debt and other items.

Who is selling JSR?

Japan Investment Corp (JIC), a state-backed fund overseen by Japan’s finance ministry. JIC took JSR private in 2024 for about 900 billion yen and then ran an auction to find a buyer.

What is a photoresist?

A photoresist is a light-sensitive coating applied to a silicon wafer during chipmaking. When light is shone through a patterned mask, the photoresist records the circuit design, which is then etched into the wafer. Without photoresists, modern chips could not be made.

What is EUV lithography?

EUV stands for extreme ultraviolet. It is the most advanced method of printing circuits onto chips, using extremely short-wavelength light to create features measured in nanometres. It is used to make the most powerful processors in phones, computers and AI data centres.

When will the deal close?

Mitsui aims to complete the acquisition in the second half of the financial year ending March 2028, between October 2027 and March 2028, subject to competition and foreign-investment approvals in Japan and other countries.

Conclusion

Mitsui Chemicals’ $11.6 billion purchase of JSR is the biggest deal Japan’s chemicals sector has ever seen, and one of the largest ever in semiconductor materials. It brings together the world’s leading maker of EUV pellicles with the world’s second-largest maker of advanced photoresists, creating a Japanese champion in the materials that make the most advanced chips possible.

The deal is a bold bet. Mitsui is paying nearly three times its own market value, funded by a huge bank loan and a share sale, and it still needs regulatory approval in several countries. But it reflects a wider shift: as artificial intelligence drives demand for ever more powerful chips, the chemicals and materials behind them have become strategically vital — and Japan is determined to keep its lead.

If the deal closes on schedule, the combined company will sit at the centre of the global chip supply chain. For the millions of people who use the phones, computers and services those chips power, the effects will be invisible — but they will be real.

Sources

• Reuters: “Mitsui Chemicals and DBJ to buy JSR for $11.6 billion, filing shows” — https://www.reuters.com/world/asia-pacific/mitsui-chemicals-dbj-buy-jsr-116-billion-filing-shows-2026-11-09/
• The Japan Times: “Mitsui Chemicals to buy JSR” — https://www.japantimes.co.jp/business/2026/11/09/companies/mitsui-chemicals-jsr-takeover/
• TechNode: “Mitsui Chemicals JSR acquisition” — https://technode.global/2026/11/09/mitsui-chemicals-jsr-acquisition/
• 985 The River (Reuters): “Mitsui Chemicals and DBJ to buy JSR for $11.6 billion, filing shows” — https://985theriver.com/2026/11/08/mitsui-chemicals-and-dbj-to-buy-jsr-for-11-6-billion-filing-shows/
• FN News: “Mitsui Chemicals to buy JSR” — https://en.fnnews.com/news/202611091159388314
• PakTechStan: “Mitsui Chemicals to buy JSR for $11.6 billion in Japan’s biggest chip materials deal” — https://paktechstan.com/article/mitsui-chemicals-to-buy-jsr-for-11-6-billion-in-japan-s-biggest-chip-materials-deal

This article is for general information and education only. It is not legal or financial advice.