There has been Mitsuibishi branded colour film for a long time. It was in ISO 100, 200 & 400 speeds but sellers on ebay only seem to sell ISO 100 at present. The close-up of the box on some of the listings says Mitsuibishi Paper Mills Ltd and made in Japan. As Konica disappeared some years back, and this stuff is fresh, I suspect it is made by Fuji. The emulsion numbers look like very much like Fuji ones. As far as I know, they are the only company in Japan still manufacturing film, but perhaps someone resident there could confirm?