Herbert Helfert
18Patents
7h-index
40Co-inventors
66Inventor score
Filing activity: Feb 19, 1974 → Nov 21, 2002
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4052159A | Dyeing process using quaternary ammonium salt as retarder | Emerging Cross-Sectional Technologies | 76 | Expired |
| US4207199A | Solid cold bleach activators for detergents and cleaning agents containing an active oxygen donor | Emerging Cross-Sectional Technologies | 23 | Expired |
| US4061684A | Highly branched polyether polyols of high molecular weight | Chemistry; Metallurgy | 15 | Expired |
| US4275244A | Linear polyalkylene ether glycols of high molecular weight | Emerging Cross-Sectional Technologies | 13 | Expired |
| US4614604A | Lubricants for shaping polyvinyl chloride, which contain esterified oligomeric polyhydric alcohols | Chemistry; Metallurgy | 10 | Expired |
| US4113785A | Polyether polyols and method of preparing same | Emerging Cross-Sectional Technologies | 9 | Expired |
| US4031112A | Cyclic acetals | Chemistry; Metallurgy | 8 | Expired |
| US3963714A | Quaternary ammonium salts | Emerging Cross-Sectional Technologies | 6 | Expired |
| US4294576A | Removal of oligomer deposits from textile materials | Textiles; Paper | 6 | Expired |
| US5710284A | Purification of N-vinylpyrrolidone by crystallization | Chemistry; Metallurgy | 4 | Expired |
| US4151127A | Process for suppressing the foaming of detergents | Chemistry; Metallurgy | 4 | Expired |
| US6703511B2 | Method for obtaining pure n-vinyl pyrrolidone | Chemistry; Metallurgy | 3 | Expired |
| US3945794A | Production of level dyeings on acrylonitrile polymer fibers with basic dyes | Emerging Cross-Sectional Technologies | 3 | Expired |
| US5461159A | Binding chemical impurities contained in crude N-vinylpyrrolid-2-one | Chemistry; Metallurgy | 2 | Expired |
| US5948945A | Prevention of spontaneous decomposition of gaseous acetylene | Chemistry; Metallurgy | 1 | Expired |
| US5723685A | Preparation of monovinyl ethers | Chemistry; Metallurgy | 1 | Expired |
| US6888006B2 | Method for processing pyrollidone and n-vinyl pyrollidone residues | Chemistry; Metallurgy | 0 | Expired |
| US4006093A | Surfactants containing iodine | Chemistry; Metallurgy | 0 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.