Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5053279 | Granular bitumen coated with carbon black or silica | Ivo Daniëls, Reinhard Manner, Walter Barthel | 1991-10-01 |
| 4993884 | Method and spraying apparatus for applying a layer of air-sprayed concrete | Walter Barthel | 1991-02-19 |
| 4375988 | Bituminous binder, process for its production and use | Walter Barthel | 1983-03-08 |