Jukan
Semiconductor & AI Infrastructure Research at Citrini
Nittobo's stock is stuck sideways because it will not raise prices despite a severe T-glass shortage. Per Japanese media reports, management plans no further price increases on low-thermal-expansion glass fabric and will instead accelerate capacity in Fukushima and Taiwan to defend market share. Unlike memory makers aggressively raising prices, Nittobo is too conservative and cares too much about customers, which is a reason not to own it. x.com x.com
Nittobo's near-monopoly in T-glass looks durable, because big tech is unlikely to risk irreversible chip problems by switching to a rival's product. Prismark expects the T-glass shortage to widen, as demand from NVIDIA, Google and Amazon, which buy only from Nittobo for AI server substrates, outpaces its capacity growth; its capacity exceeds all rivals combined. A domestic PCB industry source says the shortage will be hard to resolve unless big tech drops its Nittobo-only policy. x.com x.com
Glass fiber cloth is a huge bottleneck for GPUs, ASICs and 800G/1.6T switches, and demand is shifting to alternatives as Nittobo, with 90% of T-glass and 70% of NER-glass, lacks capacity until mid-2027. Taiwan Glass is among the strongest near-term AI plays, with low-CTE output ramped in Q1 2026 and Nvidia/AMD certification. Fulltech is moving to T-glass, and Nan Ya Plastics is integrated via Nittobo. Unitika is most compelling, with asymmetric upside if Qualcomm or hyperscalers sign long deals. … Show more
Nittobo and Ajinomoto are unlikely to deliver alpha because they will not monetize their monopoly pricing power, putting customer relationships ahead of shareholders. SK hynix and Micron raise prices when demand exceeds supply and reinvest profits to widen their technology lead; per @jukan05, Nittobo has no intention of raising prices. In fast-moving chips, customer loyalty does not merit a high valuation premium, even with Ajinomoto holding 95% of ABF film and no qualified Chinese rival yet. … Show more
The move from organic ABF substrates to glass is becoming a necessity for Nvidia's largest packages, and Nittobo, Schmid, LPKF and Ibiden sit at its choke points. Nittobo has a near-monopoly on low-CTE T-Glass fiber amid a shortage; LPKF's LIDE drilling and Schmid's inline systems ride US and EU sovereign AI pushes; Ibiden bridges ABF and glass core. Timing is the risk: TSMC pushed panel-level CoPoS to Q4 2030, so Rubin Ultra may use hybrid glass stiffeners, and Nittobo has already run 9x. x.com … Show more
Furukawa Electric is not worth chasing because companies like it will fail to raise prices on high-demand products and stay committed to low-margin, low-growth segments. This is not a rejection of growth. A post in the thread notes that end customers such as Nvidia and Micron earn 75% gross margins, yet Japanese suppliers prefer to let Americans take the margin. x.com
Unitika may be too small after its restructuring, or too early in its new cycle, to benefit from AI glass demand, so the earlier thesis was too aggressive. Glass fiber and cloth sales fell 9% year over year to ¥33.7 billion, while operating profit rose 436.5% to ¥1.6 billion on one-offs. Unlike the prior quarter's mention of vigorous AI-related E-glass demand, the latest results had no explicit AI language. Its cleaner balance sheet keeps capacity and qualification updates worth watching. x.com
High-grade PCB and low-loss glass-fiber makers Nitto Boseki, Elite Material and Taiwan Union Technology should keep rising as the obvious workaround to an inevitable memory despec for Nvidia's Rubin Ultra and Feynman. All three have more than tripled in the past year, and some are up over 10x in three years. Switching suppliers is harder here than in memory, which is why a few firms dominate, but it is higher risk and new supply coming online has not been analyzed. x.com
United Microelectronics and ABF substrate suppliers look more attractive as advanced packaging becomes heavily constrained and supply additions look gloomy. Per industry insiders, a shortage of T-Glass fiberglass cloth has stretched delivery times for high-grade ABF substrates from 12-18 weeks to over 20 weeks. Analysts expect ABF substrate prices to rise 10-15% quarter over quarter, with tight supply lasting until 2027. x.com
Ajinomoto, Nittobo, Ibiden and AT&S sit in an ABF substrate supply chain consolidated into near-monopolies, where the AI chip bottleneck keeps moving. Nvidia, Intel and AMD are prepaying for suppliers' factories, with Ibiden receiving over 90 billion yen; companies that size do not prepay unless out of options. Ajinomoto holds over 95% of the substrate film market, and Apple, Nvidia and Google are chasing Nittobo's glass fabric. A capex cycle ending in overcapacity is the risk. x.com x.com
