Issued Patents All Time
Showing 1–23 of 23 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4987221 | Bisdiazonium salts of 4,4'-diamino-3,3'-dialkoxybiphenyls and a process for their preparation | Hasso Hertel, Heinrich Frolich | 1991-01-22 |
| 4987258 | 4,4'-diaminodiphenyl compounds, process for their preparation and their use | Heinrich Frolich, Kurt Habig | 1991-01-22 |
| 4973672 | Water-soluble aminonaphthol disazo dyestuffs, their preparation and their use | Wolfgang Bauer | 1990-11-27 |
| 4906735 | Process for the manufacture of a monoazo acetoacetylaminobenzimidazolone | — | 1990-03-06 |
| 4720541 | Process for improving the application properties of disazo pigments | Wolfgang Rieper | 1988-01-19 |
| 4696675 | Process for preparing water-insoluble blue azo dyes on the fiber: hydroxynaphthoic amide and diazotized di-alkoxy-benzidine | Hasso Hertel, Heinrich Frolich | 1987-09-29 |
| 4686287 | Disazo compounds derived from acetoacetylamino-benzimidazol-2-ones | — | 1987-08-11 |
| 4677200 | Amino compounds derived from 5-acetoacetylamino-benzimidazolones | — | 1987-06-30 |
| 4665163 | Diaryl pigments with improved heat stability obtained by coupling bis-diazotized diamines with acetoacetanilides | Heinrich Frolich, Hans-Joachim Lenz | 1987-05-12 |
| 4607096 | Azo pigments obtained by diazotizing in a dipolar aprotic organic solvent | Josef Landler, Erhard Worfel | 1986-08-19 |
| 4589921 | Process for improving the application properties of pigment yellow 13 | Wolfgang Rieper | 1986-05-20 |
| 4555568 | Monoazo compounds derived from 3-nitro-4-amino-benzoates and 5-(2'-hydroxy-3'-naphthoylamino)-benzimidazolones | — | 1985-11-26 |
| 4504416 | Azo compounds deriving from amino benzoic acid anilides and acetoacetylamino-benzimidazolone | Manfred Pesenacker | 1985-03-12 |
| 4476052 | Azo pigment having improved hiding power and a process for its preparation | Joachim Ribka, Friedrich Weingarten, Wolfgang Rieper | 1984-10-09 |
| 4405793 | 1,3,4-Oxadiazoles | Otto Fuchs, Dieter Weber, Reinhard Zunker | 1983-09-20 |
| 4370269 | Monoazo pigment derived from acetoacetylamino benzimidazolone | Friedrich Weingarten, Ernst Klappert | 1983-01-25 |
| 4368155 | Monoazo compounds derived from meta-amino-benzoic acid anilides and acetoacetylamino-benzimidazolone | Manfred Pesenacker | 1983-01-11 |
| 4302388 | Monoazo compounds deriving from meta-amino-benzoic acid anilides and acetoacetyl amino-benzimidazolone | Manfred Pesenacker | 1981-11-24 |
| 4302389 | Azo compounds deriving from amino benzoic acid anilides and acetoacetylamino-benzimidazolone | Manfred Pesenacker | 1981-11-24 |
| 4287122 | Monoazo compounds from 1-aminobenzene-2-carboxylic acid derivatives and their use as colorants | Ernst Klappert, Konrad Lohe | 1981-09-01 |
| 4251441 | Pigments of mixtures of methoxynitrobenzene-azo-methoxy-acetanilides | Heinrich Frolich | 1981-02-17 |
| 4195020 | Dichloro-phenyl-azo-acetoacetylamino-benzimidazolone pigments | Joachim Ribka | 1980-03-25 |
| 4182708 | Process for the preparation of azo pigments by diazotizing in a dipolar aprotic organic solvent and azo pigments obtained therefrom | Josef Landler, Erhard Worfel | 1980-01-08 |