Inventor · disambiguated record
Guido Steffan
Also filed as: BORGMANN ERNST · STEFFAN GUIDO
40 granted patents·186 citations·filing 1978–2000
97Inventor score
Top patents by PatentIndex Score
40 records- 0181US5681957AProcess for the preparation of substituted 2-fluoro-pyrimidinesBAYER AG·Filed 1996·Granted Oct 28, 1997·27 cites·10 claims
- 0280US6355827B1Process for preparing 2-cyanoindan-1-onesBAYER AG·Filed 1998·Granted Mar 12, 2002·20 cites·10 claims
- 0373US6525198B1Method for producing 4,6-dichloropyrimidine with sulfur compounds and phosphorus compoundsBAYER AG·Filed 2000·Granted Feb 25, 2003·5 cites·10 claims
- 0473US6441171B1Method for the production of 4,6-dichloropyrimidine with the aid of phosgeneBAYER AG·Filed 2000·Granted Aug 27, 2002·5 cites·8 claims
- 0570US6296788B1Process for the preparation of Grignard reagents and novel Grignard reagentsBAYER AG·Filed 2000·Granted Oct 2, 2001·6 cites·10 claims
- 0665US4267346AProcess for the preparation of 1,2,4-triazoleBAYER AG·Filed 1979·Granted May 12, 1981·5 cites·7 claims
- 0764US6562970B1Method for producing 4-chloro-6-hydroxypyrimidineBAYER AG·Filed 2000·Granted May 13, 2003·2 cites·10 claims
- 0864US6455725B1Substituted cinnamic acids and cinnamic acid estersBAYER AG·Filed 1999·Granted Sep 24, 2002·8 cites·8 claims
- 0964US4325889AProcess for the preparation of 1-amino-8-naphthol-3,6-disulphonic acid (H-acid)BAYER AG·Filed 1980·Granted Apr 20, 1982·11 cites·5 claims
- 1062US6441170B1Method of producing 4,6-dichloropyrimidine with acid chloridesBAYER AKITNEGESELLSCHAFT·Filed 2000·Granted Aug 27, 2002·3 cites·6 claims
- 1162US5283338AProcess for the preparation of 2-chloropyridinesBAYER AG·Filed 1992·Granted Feb 1, 1994·7 cites·1 claims
- 1261US5719285AProcess for the preparation of polychloropyrimidinesBAYER AG·Filed 1995·Granted Feb 17, 1998·8 cites·14 claims
- 1359US6822095B1Method for producing 4,6-dichloropyrimidineBAYER AG·Filed 2000·Granted Nov 23, 2004·1 cites·9 claims
- 1459US5677453AProcess for the preparation of 4,6-dichloropyrimidinesBAYER AG·Filed 1996·Granted Oct 14, 1997·9 cites·10 claims
- 1557US6369259B1Method of preparing 4,5,6-trichloro-and 2,4,5,6-tetrachloropyrimidineBAYER AG·Filed 2000·Granted Apr 9, 2002·1 cites·2 claims
- 1654US5900509AProcess for the preparation of p-haloalkoxyanilinesBAYER AG·Filed 1998·Granted May 4, 1999·4 cites·10 claims
- 1751US4764621APreparation of 2-chlorobenzthiazoleBAYER AG·Filed 1983·Granted Aug 16, 1988·2 cites·6 claims
- 1850US6015771AThermally-responsive record materialBAYER AG·Filed 1998·Granted Jan 18, 2000·8 cites·17 claims
- 1949US5679826AProcess for the preparation of 2-chloroacrylonitrileBAYER AG·Filed 1996·Granted Oct 21, 1997·4 cites·10 claims
- 2048US5693831A(2,3-dihydro-5-benzofuranyl)-acetonitrileBAYER AG·Filed 1997·Granted Dec 2, 1997·3 cites·11 claims
- 2147US5872283AProcess for decarboxylation of halogenated aromatic carboxylic acidsBAYER AG·Filed 1997·Granted Feb 16, 1999·3 cites·16 claims
- 2247US4341720AProcess for the preparation of oxalyl chlorideBAYER AG·Filed 1981·Granted Jul 27, 1982·3 cites·20 claims
- 2344US5847217AProcess for the preparation of 2-amino-5-alkyl-phenolsBAYER AG·Filed 1997·Granted Dec 8, 1998·2 cites·11 claims
- 2444US4217209AProcess for removing heavy metal sulphides from aqueous systemsBAYER AG·Filed 1978·Granted Aug 12, 1980·10 cites·8 claims
- 2542US5464875AProcess for preparing weakly-basic anion exchangers and reagents suitable for this purposeBAYER AG·Filed 1994·Granted Nov 7, 1995·7 cites·2 claims
- 2641US6433228B1Process for preparing 2-halogenated indan-1-onesBAYER AG·Filed 1998·Granted Aug 13, 2002·2 cites·5 claims
- 2741US6294502B1Thermally-responsive record materialBAYER AG·Filed 1999·Granted Sep 25, 2001·5 cites·10 claims
- 2841US6162917AMethod of preparing 4,5,6-trichloro- and 2,4,5,6-tetrachloropyrimidineBAYER AG·Filed 1997·Granted Dec 19, 2000·2 cites·12 claims
- 2940US6184417B1Method for preparing acetophenones with a fluoralkyl-substituted aromatic nucleusBAYER AG·Filed 1998·Granted Feb 6, 2001·2 cites·9 claims
- 3040US4760209AProcess for preparing 3,5-dichloro-α-methylstyreneBAYER AG·Filed 1986·Granted Jul 26, 1988·2 cites·17 claims
- 3139US4180521AProcess for the preparation of naphthalene-1,3,6-trisulphonic acidBAYER AG·Filed 1978·Granted Dec 25, 1979·1 cites·11 claims
- 3236US4600542ASulphonation products of naphthalene, processes for their preparation, and their useKRAMER AG·Filed 1981·Granted Jul 15, 1986·2 cites·4 claims
- 3336US4163752AProcess for the preparation of aminonaphthalenesulphonic acidsBAYER AG·Filed 1978·Granted Aug 7, 1979·2 cites·18 claims
- 3435US6504059B1Process for converting nitrobenzene to a free aminophenolBAYER AG·Filed 1999·Granted Jan 7, 2003·0 cites·7 claims
- 3535US6025499AProcess for the preparation of a nitropyrazole amideBAYER AG·Filed 1999·Granted Feb 15, 2000·0 cites·3 claims
- 3634US5969152AProcess for the preparation of nitropyrazole estersBAYER AG·Filed 1997·Granted Oct 19, 1999·0 cites·6 claims
- 3733US5723613AProcess for the free-radical chlorination or bromination of methyl aromatic compoundsBAYER AG·Filed 1992·Granted Mar 3, 1998·1 cites·14 claims
- 3832US6197964B1Method for the production of 2,6-dichloro-5-fluoronicotinonitrile and the chemical compound 3-cyano-2-hydroxy-5-fluoropyride-6-one-monosodium salt its tautomersBAYER AG·Filed 1998·Granted Mar 6, 2001·1 cites·10 claims
- 3931US5144065AProcess for the preparation of aminoarylsulphonic acidsBAYER AG·Filed 1991·Granted Sep 1, 1992·1 cites·4 claims
- 4031US4348334AProcess for producing the magnesium salt of 3-nitro-naphthalene-1,5-disulfonic acid (nitro-Armstrong's acid)CIBA GEIGY AG·Filed 1980·Granted Sep 7, 1982·1 cites·16 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →