Then there is Ajinomoto ($2802.T).

Ajinomoto controls roughly 95% of the ABF film market. ABF is the insulating film laminated between the copper layers of an advanced substrate. So while MEC captures the chemistry required to process the substrate, Ajinomoto supplies one of the critical materials that actually builds it.

The economics are particularly interesting.
Functional Materials was ~30% of FY25 sales, but contributed ~83% of business profit. The segment runs at >50% operating margins. And Ajinomoto’s film consumption scales with layer count and substrate form factor. As substrates get larger and have more layers, ABF content rises with them. This means a relatively small business inside a much larger company is directly exposed to
one of the most constrained and rapidly growing parts of the AI hardware stack. (6/7)