Number | Name | Date | Kind |
---|---|---|---|
2591379 | Schradermeier | Apr 1952 | |
4111813 | Preus | Sep 1978 | |
4668201 | Stark | May 1987 | |
4821670 | Foxcroft | Apr 1989 | |
5002511 | Maki | Mar 1991 |
Number | Date | Country |
---|---|---|
0523977 | Feb 1956 | BEX |
0269431 | Jun 1988 | EPX |
Entry |
---|
"Pelaspan Expandable Polystyrene", Catalog 171-90, Dow Chemical Company, Feb. 1958, p. 32. |