Number | Date | Country | Kind |
---|---|---|---|
2404999 | Feb 1974 | DT |
Number | Name | Date | Kind |
---|---|---|---|
2109514 | Van Duzee et al. | Mar 1938 | |
2121723 | Bass et al. | Jun 1938 | |
2121724 | Bass et al. | Jun 1938 | |
3450772 | Bridger et al. | Jun 1969 | |
3654364 | Meckel et al. | Apr 1972 |
Entry |
---|
Powanol -- Glycol Ether Solvents (1957), p. 3. |
Number | Date | Country | |
---|---|---|---|
Parent | 541669 | Jan 1975 |