| Number | Date | Country | Kind |
|---|---|---|---|
| 5-082576 | Mar 1993 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 4788599 | Sugishima | Nov 1988 | |
| 4816867 | Ito | Mar 1989 | |
| 4941017 | Mishima et al. | Jul 1990 | |
| 5001574 | Shimizu | Mar 1991 | |
| 5049932 | Sumida | Sep 1991 |
| Entry |
|---|
| Patent Abstracts of Japan, JP 1-219852, Sep. 1, 1989. |
| Patent Abstracts of Japan, JP 63-179662, Jul. 23, 1988. |