Issued Patents All Time
Showing 51–58 of 58 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4578202 | Cutting oil for working nonferrous metals by cutting | Dieter Schmitt | 1986-03-25 |
| 4496731 | Process for the preparation of perylene-3,4,9,10-tetracarboxylic acid N,N'- d | Ernst Spietschka | 1985-01-29 |
| 4460410 | Process for the manufacture of a perylene tetracarboxylic acid dianhydride pigment | Ernst Spietschka | 1984-07-17 |
| 4456762 | Process for the preparation of 4,7-dichloro-3-hydroxy-thionaphthene | Ernst Spietschka | 1984-06-26 |
| 4431806 | Process for the preparation of pigments of the perylene-3,4,9,10-tetracarboxylic acid diimide series, and their use | Ernst Spietschka | 1984-02-14 |
| 4284789 | Thio-indigo dyestuffs | Ernst Spietschka | 1981-08-18 |
| 4253839 | Process for the fine distribution of pigments of the dioxazine series | Ernst Spietschka, Erich Paulus | 1981-03-03 |
| 4229583 | Process for preparing thio-indigo dyestuffs | Ernst Spietschka | 1980-10-21 |