| Number | Name | Date | Kind |
|---|---|---|---|
| 4130603 | Tanaka et al. | Dec 1978 | |
| 5269950 | Iwamoto et al. | Dec 1993 |
| Entry |
|---|
| Chemical Abstract No. 93:48470, abstract of Japanese Patent Specification No. 55-030413, Mar. 1980. |
| Chemical Abstract No. 103:197234, abstract of German Patent Specification No. 221772, May 1985. |
| Chemical Abstract No. 115:138127, abstract of Japanese Patent Specification No. 03-040867, Feb. 1991. |
| Chemical Abstract No. 115:138162, abstract of Japanese Patent Specification No. 03-040873, Feb. 1991. |