| Number | Name | Date | Kind | 
|---|---|---|---|
| 4232112 | Kuse | Nov 1980 | |
| 4587195 | Ishikawa et al. | May 1986 | |
| 4895786 | Kurematsu et al. | Jan 1990 | |
| 5043253 | Ishikawa | Aug 1991 | |
| 5147765 | Goto et al. | Sep 1992 | |
| 5221597 | Fujita et al. | Jun 1993 | 
| Number | Date | Country | 
|---|---|---|
| 2203302 | Jun 1973 | DEX | 
| 10104809 | JPX | |
| 58-222156 | Dec 1983 | JPX | 
| 1158443 | Mar 1989 | JPX | 
| 1062642 | Nov 1989 | JPX | 
| Entry | 
|---|
| Research Disclosure 37336 and 20733. |