Rumored Japan photoresist ban sparks Chinas worst fears

Chinese online forums and market chatters have recently been engulfed by speculation that Japan may have halted the export of photoresist, a critical material for semiconductor manufacturing exports, to China.

Although the Japanese government and major Japanese suppliers have made no public announcements, unverified claims alleging that “Canon, Nikon and Mitsubishi Chemical have suspended photoresist shipments to China” spread rapidly across Chinese social media around November 18 to 19, when Chinese and Japanese officials were holding meetings in Beijing to try to ease the rising political tensions between the two countries.

According to the claims, the three Japanese companies had allegedly tightened raw‑material supplies and slowed equipment servicing, creating delays that would ripple through the supply chain. Rather than any formal ban, the claims suggested a pattern of postponed approvals, stretched delivery timelines and reduced technical support that collectively disrupted operational stability.

In fact, Canon and Nikon produce not photoresist but lithography machines and parts, while Mitsubishi Chemical makes Lithomax, a raw material for photoresist manufacturers.

The rumors appeared to be spread by Chinese stock speculators. They went viral alongside reports about Beijing’s decision to halt all imports of Japanese seafood to retaliate against Japan’s Prime Minister Sanae Takaichi’s pro-Taiwan comments.

Beneficiaries of the rumors were shareholders in Chinese firms that might be called upon to try to fill any such gap in supply of photoresist. In the four trading days between November 19 and 24, shares of several Chinese photoresist suppliers and companies labeled with the “photoresist concept” saw notable gains.

Anhui Guofeng New Materials Co Ltd surged 46.5%, while Jiangsu Nata Opto-electronic Materials Co Ltd advanced 11.1%. Red Avenue New Materials Group Co Ltd, the parent company of Beijing Kehua, climbed 14.1% over the same period.

Not all firms benefited. Shares of Shanghai-listed HMT (Xiamen) New Material Technology Co Ltd, owner of Xuzhou B&C Chemical Technology Co Ltd, declined 4.3%. The company’s diversified portfolio, which includes auto parts and fiber products, may have dampened investor enthusiasm for its photoresist exposure.

Photoresist is central to lithography, acting as the light‑sensitive coating that transfers circuit patterns onto silicon wafers. High‑purity formulations are essential, as small inconsistencies can cause defects or production delays. Foundries therefore rely heavily on Japanese suppliers, whose decades of investment and proprietary chemistries underpin their dominance in both mainstream and high‑end segments.

Short-term disruption

While it remains difficult to verify whether Japan has imposed or will launch any export restrictions, the sense of alarm among Chinese commentators continues to deepen.

“Japan’s alleged moves amount to a precise strike on China’s semiconductor supply chain,” a Beijing‑based columnist using the pen name “Diudiu” says in an article. “If raw‑material supplies and equipment maintenance remain disrupted, some wafer‑fabrication plants in China may face complete production shutdowns within a month.”

He says Japan controls over 70% of the global photoresist market, and an astonishing 95% market share for photoresists used in extreme ultraviolet (EUV) lithography. He saysChina can only self-supply5% of the photoresists used in krypton fluoride (KrF) deep ultraviolet (DUV) lithography, and relies totally on Japan’s supply for photoresists used in argon fluoride (ArF)DUV lithography.

KrF DUV lithography is typically used for making 110 to 180 nanometer (nm) chips, while ArF DUV lithography is used for producing 7 to 65 nm chips.

Diudiu says Beijing has already moved to strengthen China’s photoresist capabilities through three initiatives:

• launching China’s first EUV photoresist testing standard in October 2025 to provide a clearer technical framework for domestic development;
• directing the second phase of the National Integrated Circuit Industry Investment Fund to prioritize core materials such as photoresist, ensuring sustained financial backing; and
• urging domestic foundries to adjust procurement strategies by giving greater priority to qualified local photoresist products.

“Japan now controls over 90% of the global high‑end photoresist market and accounts for nearly half of all related patent filings,” says a Zhejiang‑based columnist under the pseudonym “Kong Yiji.”

“Even US and Korean chip giants ultimately depend on Japanese photoresists,” he says. “Tokyo invested early in large‑scale IC‑materials programs, backed by state funding and coordinated research and development, enabling Japanese firms to dominate the full chain from photo‑sensitive resins to additives.”

“When Japan’s Shin‑Etsu Chemical cited production constraints and halted deliveries of photoresists to China in 2021, Semiconductor Manufacturing International Corp (SMIC)’s efficiency dropped by 20%. After Chinese fabs ran out of photoresist inventory,Yangtze Memory had to delay its chip deliveries to mobile and automobile makers.”

Kongsays China has been investing heavily in semiconductor materials and is pursuing a multi‑channel sourcing strategy in recent years. He says imports will still dominate, but China targets to self-supply 40% of the photoresists it needs in 2026.

Kong adds that Kehua has advanced KrF photoresists covering the making of 45-nanometer chips, whilea research team at Peking University has successfully enhanced photoresist stability, gradually extending applicability from 28nm toward more advanced nodes.”

He concludes that these efforts underscore a broader national push to cultivate upstream capabilities, signalling that while Japan’s dominance remains formidable, China’s incremental breakthroughs point to a long‑term shift in materials innovation and supply‑chain resilience.

China’s ultimate deterrence

In July 2019 amid a sovereignty dispute, Japan imposed licensing requirements on exports of three key materials to South Korea: fluorinated polyamides, photoresists and hydrogen fluoride. The chemicals are essential for producing memory chips and smartphones.

The move immediately tightened supply for Samsung Electronics and SK Hynix, which together hold more than 60% of the global memory‑chip market. Tokyo lifted those restrictions in March 2023 as ties with Seoul improved.

“Photoresists typically have a shelf life of only six to 12 months, so large‑scale stockpiling is unrealistic,”writes a Henan‑based columnist using the pseudonym “Mao Ke.” “For large fabs such as SMIC and Hua Hong, any instability in photoresist supply could force advanced production lines to scale back output.”

Mao says that if Japan pushed forward a full photoresist embargo, China would respond with a rare‑earth export ban. He says China controls roughly 90% of the world’s rare‑earth supply, while Japan’s electric vehicle and magnet industries rely heavily on these materials.

He adds that any rare‑earth export curbs would leave Japanese firms facing the same losses seen by Shin‑Etsu Chemical in 2010.

In 2010, Beijing briefly halted rare‑earth exports to Japan during a territorial dispute. At the time, Japan imported about 28,000 metric tons a year, roughly 90% from China.

The shock pushed Japanese companies to diversify rapidly by building several overseas facilities, and Shin‑Etsu Chemical opened a recycling plant in Vietnam capable of recovering around 1,000 tonnes annually from discarded electronics. Japan and Western partners later filed a complaint to the World Trade Organization (WTO), which in August 2014 ruled against China’s export controls.

Read: China’s economic retaliation against Takaichi is just beginning

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