Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4855458 | Manufacture of phthalic anhydride by gas phase oxidation of a mixture of o-xylol and naphthalene | Werner Fuhrmann, Manfred zur Hausen | 1989-08-08 |
| 4681046 | Method of utilizing distillation residues of phthalic acid anhydride or maleic acid anhydride | Helmut Scharf | 1987-07-21 |