| Number | Name | Date | Kind |
|---|---|---|---|
| D183180 | Phillips | Jul 1958 | |
| D185717 | Newton | Jul 1959 | |
| D231624 | Wilmoth | May 1974 | |
| D268357 | Mader | Mar 1983 | |
| D277221 | Kobayashi | Jan 1985 | |
| D298767 | Szczepanski | Nov 1988 | |
| D307783 | Iinuma | May 1990 | |
| D316583 | Mahaffey et al. | Apr 1991 | |
| 1317146 | Welles | Sep 1919 | |
| 1418038 | Tousey | May 1922 | |
| 1431313 | Lawton | Oct 1922 | |
| 1526438 | Scott | Feb 1925 | |
| 1587758 | Charavay | Jun 1926 | |
| 1662712 | Mensing | Mar 1928 | |
| 1781290 | Margrave | Nov 1930 | |
| 1974389 | Cowdery | Sep 1934 | |
| 2020679 | Fitzpatrick | Nov 1935 | |
| 2023885 | Hinckley | Dec 1935 | |
| 2083189 | Crooker | Jun 1937 | |
| 2573361 | Rodgers, Jr. et al. | Oct 1951 | |
| 2822175 | Redmond | Apr 1958 | |
| 2912245 | Gardner | Nov 1959 | |
| 3416798 | Pennington | Dec 1968 | |
| 3458611 | Roberts | Jul 1958 | |
| 3469338 | Hills | Sep 1969 | |
| 3625518 | Solheim | Dec 1971 | |
| 4498673 | Swanson | Feb 1985 | |
| 4648598 | Kim | Mar 1987 | |
| 4757997 | Roy | Jul 1988 | |
| 5042805 | Nakai | Aug 1991 | |
| 5092599 | Okumoto et al. | Mar 1992 | |
| 5190289 | Nagai et al. | Mar 1993 |
| Number | Date | Country |
|---|---|---|
| 2581319 | Nov 1986 | FRX |
| 16471 | Jan 1910 | GBX |
| 373930 | Jun 1932 | GBX |
| 462155 | Mar 1937 | GBX |
| Entry |
|---|
| "Plastics World", Magazine, Sep. 1984 issue, pp. 39-41. |