Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6684910 | Multi-layered pipe | Volker Koestring, Ali Guettouche, Helmut Schroeder | 2004-02-03 |
| 4495128 | Method for coloring polyvinylchloride | — | 1985-01-22 |
| 4477678 | Sulfur-containing flavoring agents | Steven van den Bosch, Dirk K. Kettenes, Kris B. de Ross, Gerben Sipma | 1984-10-16 |
| 4414233 | Methylthiomethyl esters as flavor additives | Steven van den Bosch, Evert van't Land | 1983-11-08 |
| 4380655 | Novel sulfur-containing flavoring agents | Steven van den Bosch, Dirk K. Kettenes, Kris Bart de Roos, Gerben Sipma | 1983-04-19 |
| 4339278 | Coloring composition for coloring thermoplastic polymers | — | 1982-07-13 |
| 4332829 | Methylthiomethyl esters as flavor additives | Steven van den Bosch, Evert van't Land | 1982-06-01 |