Inventor · Heidelberg, DE

Erwin Hahn

51Patents
9h-index
87Co-inventors
77Inventor score

Filing activity: Jul 17, 1978 → Jan 10, 1995

Most-cited inventions

PatentTitleAreaCited byStatus
US5076808A Dyeing of polyamide substrates with an organic N-nitroso-hydroxylamine as light stabilizer Emerging Cross-Sectional Technologies 56 Expired
US5470502A Fluorescent pigments Chemistry; Metallurgy 54 Expired
US4286959A Disperse dye formulations Textiles; Paper 15 Expired
US5306815A Azo dyes with a coupling component of the quinoline series Chemistry; Metallurgy 15 Expired
US4846892A Tetrachloroperylene-3,4,9,10-tetracarboxylic acid diimide pigment and its use Chemistry; Metallurgy 13 Expired
US5410053A Rhodamine derivatives Physics 13 Expired
US5382476A Recycling of cured aminoplast resins Emerging Cross-Sectional Technologies 12 Expired
US4670591A Preparation of N-.alpha.-alkoxyethylformamides Chemistry; Metallurgy 10 Expired
US4668775A .alpha.-methine substituted thiophene monoazo dye Emerging Cross-Sectional Technologies 9 Expired
US4885396A Process for the preparation of 2-hydroxy-4-(2'-hydroxyethoxy) benzophenones Chemistry; Metallurgy 7 Expired
US4908041A Navy and black dye mixtures: thiophene azo disperse dye and red, yellow or orange disperse dye Emerging Cross-Sectional Technologies 6 Expired
US5560961A Process of making metal-coated melamine/formaldehyde resin fibers Textiles; Paper 6 Expired
US5154763A Stabilized aqueous alkyldiketene emulsions Textiles; Paper 6 Expired
US5131981A Coloring paper Textiles; Paper 6 Expired
US4751288A Azo dyes containing 2-amino-3-cyano-5-formylthiophene derivatives as diazo components and substituted aniline compounds as coupling components Emerging Cross-Sectional Technologies 5 Expired
US5112362A Navy dye mixtures of azo disperse dyes for polyester Emerging Cross-Sectional Technologies 5 Expired
US5286401A Use of heterocyclic compounds as bleach activators or optical brighteners in washing and cleaning agents Chemistry; Metallurgy 5 Expired
US4393005A Cationic phthalocyanine dyes Chemistry; Metallurgy 5 Expired
US4764599A Disazo compounds containing an N,N-bis(2-amino-benzoyl)piperazine derivative as the diazo component Emerging Cross-Sectional Technologies 5 Expired
US5356938A Recycling of cured aminoplast resins Emerging Cross-Sectional Technologies 4 Expired
US5051504A Doubled triphenylmethane dyes having bis acylpiperazine linkage Chemistry; Metallurgy 4 Expired
US4694075A Bisazo compounds containing anthranilic acid and thiazole moieties Chemistry; Metallurgy 4 Expired
US5270456A Azo dyes with A2-aminothiophene dye azo component and a coupling component and coupling component of the diphenylamine series Emerging Cross-Sectional Technologies 3 Expired
US4970321A Preparation of cyclic N,N'-dimethylureas Chemistry; Metallurgy 3 Expired
US5062861A Novel navy and black disperse dye mixtures including amino-phenyl thiophene azo disperse dye and red, yellow or orange disperse dyes Emerging Cross-Sectional Technologies 2 Expired

Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.