| Number | Date | Country | Kind |
|---|---|---|---|
| 5-206530 | Aug 1993 | JPX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2590529 | Gillies et al. | Mar 1952 | |
| 4228124 | Kashihara et al. | Oct 1980 |
| Entry |
|---|
| Patent Abstracts of Japan, vol. 016, No. 244 (C-0947), 4 Jun. 1992. |
| Patent Abstracts of Japan, vol. 007, No. 252 (C-194), 9 Nov. 1983. |
| Patent Abstracts of Japan, Section Ch, Week 7951, Derwent Publications Ltd., London, GB. |