Inventor · Frankfurt am Main, DE

Siegfried Schiessler

15Patents
6h-index
12Co-inventors
63Inventor score

Filing activity: Dec 21, 1973 → Jun 7, 1995

Most-cited inventions

PatentTitleAreaCited byStatus
US5071482A Pigment preparations Chemistry; Metallurgy 9 Expired
US4018791A Process for the preparation of highly pure halogenated phthalocyanine pigment Chemistry; Metallurgy 9 Expired
US5071483A Process for the preparation of pigment preparations of the anthanthrone series Chemistry; Metallurgy 9 Expired
US3972987A Process for regenerating sulfuric acid Chemistry; Metallurgy 9 Expired
US4010240A Process for the regeneration of sulfuric acid Chemistry; Metallurgy 7 Expired
US4224222A Process for preparing copper phthalocyanine pigments of the .alpha.-modification Chemistry; Metallurgy 7 Expired
US4153602A Process for the preparation of a N,N'-dimethyl-perylene-3,4,9,10-tetracarboxylic acid diimide pigment Chemistry; Metallurgy 6 Expired
US5698705A Isoindoline pigments Chemistry; Metallurgy 6 Expired
US4056534A Process for preparing copper phthalocyanine pigments of the .alpha.-modification Chemistry; Metallurgy 5 Expired
US5329046A Biscationic acid amide and imide derivatives and processes for their preparation Chemistry; Metallurgy 2 Expired
US4599431A Process for the preparation of naphthalene-1,4,5,8-tetracarboxylic acid and its 1,8-monoanhydride in a high degree of purity Chemistry; Metallurgy 2 Expired
US5074919A Preparation of vat dyes and pigments of the perinone series Chemistry; Metallurgy 1 Expired
US4684753A Process for preparing 1,3,6,8-tetrabromopyrene Chemistry; Metallurgy 1 Expired
US4010180A Process for the purification of copper phthalocyanine Chemistry; Metallurgy 1 Expired
US4939193A Use of the alpha-modification of cis-naphthoylenebis(benzimidazole) for pigmenting polyolefins Chemistry; Metallurgy 0 Expired

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