This is another example of the role Kumamoto plays in high-tech production in Japan. Kyushu is sometimes called Japan’s “silicone island.” See the following pdf for a detailed discussion of that aspect of Kyushu’s economy:

http://www.siiq.jp/en/pdf/map_of_major.pdf

http://www.imaging-resource.com/news/2016/05/27/ricoh-warns-of-possible-production-delays-in-wake-of-kumamoto-earthquakes