Issued Patents All Time
Showing 26–50 of 52 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4477489 | Method of making magnetic recording medium | Akio Yanai, Ryuji Shirahata | 1984-10-16 |
| 4475946 | Ferromagnetic metal particles of iron alloyed with Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Si, P, Mo, Sn, Sb and Ag coated with mono- or dialkoxysilanes | Akihiro Matsufuji, Shizuo Umemura, Masashi Aonuma, Hajime Miyatsuka | 1984-10-09 |
| 4448843 | Magnetic recording medium | Yasuyuki Yamada, Ryuji Shirahata, Akio Yanai | 1984-05-15 |
| 4446816 | Apparatus for manufacturing a magnetic recording medium | Ryuji Shirahata | 1984-05-08 |
| 4442159 | Magnetic recording medium | Shin-ichiro Dezawa, Goro Akashi | 1984-04-10 |
| 4439795 | Magnetic recording medium | Goro Akashi | 1984-03-27 |
| 4439796 | Magnetic recording medium | Goro Akashi | 1984-03-27 |
| 4437882 | Ferromagnetic powder treated with an organic silane compound | Shizuo Umemura, Akihiro Matsufuji, Masashi Aonuma, Hajime Miyatsuka | 1984-03-20 |
| 4414271 | Magnetic recording medium and method of preparation thereof | Ryuji Shirahata, Yasuyuki Yamada, Goro Akashi | 1983-11-08 |
| 4414270 | Magnetic recording medium | Takahito Miyoshi, Toshimitu Okutu, Goro Akashi, Masaaki Fujiyama | 1983-11-08 |
| 4412507 | Magnetic recording medium manufacturing device | Ryuji Shirahata | 1983-11-01 |
| 4410565 | Method of making a magnetic recording medium | Ryuji Shirahata, Yasuo Tamai | 1983-10-18 |
| 4409281 | Magnetic recording medium | Goro Akashi | 1983-10-11 |
| 4395439 | Method of manufacturing magnetic recording medium | Ryuji Shirahata | 1983-07-26 |
| 4368237 | Process for producing magnetic recording device | Yasuyuki Yamada, Goro Akashi | 1983-01-11 |
| 4354908 | Process for the production of magnetic recording members | Ryuji Shirahata, Yasuo Tamai, Masaaki Suzuki | 1982-10-19 |
| 4333985 | Magnetic recording medium | Ryuji Shirahata, Akio Yanai | 1982-06-08 |
| 4333988 | Magnetic recording media | Yasuyuki Yamada, Kenichi Masuyama | 1982-06-08 |
| 4286299 | Magnetic head assembly for recording or reproducing vertically magnetized records | Ryuji Shirahata | 1981-08-25 |
| 4267207 | Process for producing cobalt-containing ferromagnetic iron oxide powder | Koji Sasazawa, Goro Akashi, Kouichi Masaki, Shinichiro Dezawa | 1981-05-12 |
| 4260466 | Method of producing magnetic recording medium | Ryuji Shirahata, Yasuyuki Yamada, Goro Akashi | 1981-04-07 |
| 4251843 | Disc jacket for retaining magnetic recording disc | Kenichi Masuyama, Yasuyuki Yamada | 1981-02-17 |
| 4250225 | Process for the production of a magnetic recording medium | Ryuji Shirahata, Masaaki Suzuki, Hiroshi Amari | 1981-02-10 |
| 4241368 | Magnetic sheet recorder with a magnetic sheet surface treating means | Eiichi Tadokoro | 1980-12-23 |
| 4226681 | Process for the production of a magnetic recording medium | Ryuji Shirahata | 1980-10-07 |