Willi Helfer
10Patents
3h-index
18Co-inventors
53Inventor score
Filing activity: Jul 21, 1997 → Dec 30, 2008
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US5808073A | Preparation and purification of perylene-3,4-dicarbimides | Chemistry; Metallurgy | 24 | Expired |
| US6136976A | Process for producing perylene-3, 4-dicarboxylic acid imides | Chemistry; Metallurgy | 10 | Expired |
| US7145010B2 | Tert-alkylphenoxy-substituted polycyclic compounds | Chemistry; Metallurgy | 4 | Expired |
| US7446198B2 | 9-Cyano-substituted perylene-3, 4-dicarboxylic monoimides | Physics | 1 | Expired |
| US7358362B2 | Method for the production of terylene-3,4:11,12-tetracarboxydiimides by direct synthesis | Chemistry; Metallurgy | 1 | Expired |
| US7393956B2 | Method for the production of perylen-3,4:9,10-tetracarboxylic acid diimides and perylen-3,4:9,10-tetracarboxylic acid dianhydride and naphtalene-1,8-dicarboxylimides | Chemistry; Metallurgy | 0 | Expired |
| US7550606B2 | 9-cyano-substituted perylene-3,4-dicarboxylic acid monoimides | Physics | 0 | Active |
| US7851628B2 | Conversion of perylene-3,4:9,10-tetracarboximides to a form suitable for use as fluorescent dyes | Chemistry; Metallurgy | 0 | Active |
| US7807836B2 | Preparation of perylen-3,4:9,10-tetracarboxylic dianhydride and also of naphtalene-1,8-dicarboximides | Chemistry; Metallurgy | 0 | Active |
| US7753967B2 | Method for converting perylen-3,4:9,10-tetracarboxylic acid diimides into a form suitable for use as a fluorescent dye | Chemistry; Metallurgy | 0 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.