Issued Patents All Time
Showing 26–46 of 46 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5512686 | Method for the purification of dioxydiphthalic anhydride and ester intermediate made therein | Willis T. Schwartz, Frank J. Dinan | 1996-04-30 |
| 5498691 | Bis-m-benzotrifluoride compounds | Henry Lin, Robert A. Buchanan, Robert L. Ostrozynski | 1996-03-12 |
| 5484879 | Polyimides containing fluorine | Robert A. Buchanan, Ronald F. Spohn | 1996-01-16 |
| 5475149 | Method for ether formation | Robert A. Buchanan, Henry Lin | 1995-12-12 |
| 5322954 | Synthesis of 4-substituted phthalic anhydrides | Karl W. Seper, Gary H. Olsen | 1994-06-21 |
| 5304682 | Method of making 1,1'-sulfonylbis[3-nitro-5-(trifluoromethyl)benzene] | Henry Lin | 1994-04-19 |
| 5294738 | Process for selective hydrodefluorination | Lawrence B. Fertel, William S. Derwin | 1994-03-15 |
| 5185471 | Method for ether formation | Robert A. Buchanan | 1993-02-09 |
| 5185451 | Bis-imides of dioxydiphthalic acid | Willis T. Schwartz, Frank J. Dinan | 1993-02-09 |
| 5166404 | Dioxydiphthalic acid esters | Willis T. Schwartz, Frank J. Dinan | 1992-11-24 |
| 5153335 | Process for the preparation of oxydiphthalic anhydride and acyloxyphthalic anhydrides | — | 1992-10-06 |
| 5117002 | Preparation of diphenyl ether | Robert A. Buchanan | 1992-05-26 |
| 5101006 | Polyimides and copolyimides based on halo-oxydiphthalic anhydrides | Willis T. Schwartz | 1992-03-31 |
| 5089631 | Dioxydiphthalic anhydride | Willis T. Schwartz | 1992-02-18 |
| 5003086 | Process of preparing dioxydiphthalic anhydride | Willis T. Schwartz | 1991-03-26 |
| 5003031 | Polyimides and co-polyimides based on dioxydiphthalic anhydride | Willis T. Schwartz | 1991-03-26 |
| 4990670 | Method of making 1,1'-oxybis (3-nitro-5-trifluoromethyl)-benzene | Henry Lin | 1991-02-05 |
| 4978798 | Method of making halobenzophenones and intermediates thereof | — | 1990-12-18 |
| 4948904 | Process for the preparation of oxydiphthalic anhydrides | — | 1990-08-14 |
| 4946985 | Catalyzed process for the preparation of oxydiphthalic anhydrides | — | 1990-08-07 |
| 4943642 | Halo-oxydiphthalic anhydrides | Willis T. Schwartz | 1990-07-24 |