Inventor · disambiguated record
Ernst Spietschka
Also filed as: SPIETSCHKA ERNST
43 granted patents·479 citations·filing 1973–1990
98Inventor score
Files withHOECHST AG43
Top patents by PatentIndex Score
43 records- 0196US4253839AProcess for the fine distribution of pigments of the dioxazine seriesHOECHST AG·Filed 1978·Granted Mar 3, 1981·34 cites·15 claims
- 0295US4496731AProcess for the preparation of perylene-3,4,9,10-tetracarboxylic acid N,N'-dHOECHST AG·Filed 1983·Granted Jan 29, 1985·30 cites·10 claims
- 0394US4599408APerylene-3,4,9,10-tetracarboxylic acid monoanhydride monoimidesHOECHST AG·Filed 1984·Granted Jul 8, 1986·27 cites·4 claims
- 0494US4431806AProcess for the preparation of pigments of the perylene-3,4,9,10-tetracarboxylic acid diimide series, and their useHOECHST AG·Filed 1981·Granted Feb 14, 1984·28 cites·7 claims
- 0591US4709029AProcess for the preparation of perylene-3,4,9,10-tetracarboxylic acid monoanhydride monoimidesHOECHST AG·Filed 1986·Granted Nov 24, 1987·32 cites·6 claims
- 0689US4714666APerylene tetracarboxylic acid imide pigments in an electrophotographic recording materialHOECHST AG·Filed 1986·Granted Dec 22, 1987·37 cites·16 claims
- 0788US4501906AMonoalkali metal salts of perylene-3,4,9,10-tetracarboxylic acid monoanhydride and process for their manufacturingHOECHST AG·Filed 1983·Granted Feb 26, 1985·24 cites·8 claims
- 0884US4018791AProcess for the preparation of highly pure halogenated phthalocyanine pigmentHOECHST AG·Filed 1973·Granted Apr 19, 1977·12 cites·2 claims
- 0981US4594420APerylene-3,4,9,10-tetracarboxylic acid monoanhydride monoimide and monoimidazolide compounds, processes for their preparation and their useHOECHST AG·Filed 1984·Granted Jun 10, 1986·13 cites·7 claims
- 1080US4831140AProcess for the preparation of arylimides of perylene-3,4,9,10-tetracarboxylic acidHOECHST AG·Filed 1986·Granted May 16, 1989·16 cites·7 claims
- 1180US4705572AProcess for the preparation of pigments of the anthanthrone seriesHOECHST AG·Filed 1986·Granted Nov 10, 1987·14 cites·5 claims
- 1279US4124768AProcess for preparing pure substituted 2,5-diarylamino-terephthalates and the corresponding free acidsHOECHST AG·Filed 1976·Granted Nov 7, 1978·12 cites·17 claims
- 1379US4116923ADyed polyesters, process for their preparation and their use for the dyeing of plasticsHOECHST AG·Filed 1977·Granted Sep 26, 1978·24 cites·15 claims
- 1478US3939093ADaylight fluorescent pigmentsHOECHST AG·Filed 1974·Granted Feb 17, 1976·9 cites·12 claims
- 1575US5154770AMix-crystal pigments based on perylenetetracarbimides, process for their preparation and their useHOECHST AG·Filed 1990·Granted Oct 13, 1992·13 cites·2 claims
- 1675US4797162AProcess for the preparation of perylene-3,4,9,10-tetracarboxylic acid N,N'-dHOECHST AG·Filed 1986·Granted Jan 10, 1989·11 cites·3 claims
- 1775US4588814AProcess for the preparation of 3,4,9,10-perylenetetracarboxylic acid diimideHOECHST AG·Filed 1984·Granted May 13, 1986·10 cites·1 claims
- 1874US4758665AProcess for preparing high-hiding gamma-modification of unsubstituted linear transquinacridoneHOECHST AG·Filed 1986·Granted Jul 19, 1988·11 cites·15 claims
- 1974US4224222AProcess for preparing copper phthalocyanine pigments of the α-modificationHOECHST AG·Filed 1978·Granted Sep 23, 1980·8 cites·4 claims
- 2073US4655845AProcess for preparing organic pigments having excellent application propertiesHOECHST AG·Filed 1985·Granted Apr 7, 1987·10 cites·4 claims
- 2173US4153602AProcess for the preparation of a N,N'-dimethyl-perylene-3,4,9,10-tetracarboxylic acid diimide pigmentHOECHST AG·Filed 1976·Granted May 8, 1979·8 cites·11 claims
- 2272US4742170AMix-crystal pigments based on perylenetetracarbimides, process for their preparation, and their useHOECHST AG·Filed 1985·Granted May 3, 1988·10 cites·4 claims
- 2369US4769460AMix-crystal pigments based on perylenetetracarbimides, process for preparing and their useHOECHST AG·Filed 1988·Granted Sep 6, 1988·9 cites·1 claims
- 2469US4002642AProcess for the preparation of polyhalo copper phthalocyaninesHOECHST AG·Filed 1975·Granted Jan 11, 1977·8 cites·11 claims
- 2562US4212975AProcess for the manufacture of the gamma-crystal modification of linear trans-quinacridoneHOECHST AG·Filed 1978·Granted Jul 15, 1980·5 cites·11 claims
- 2662US4056534AProcess for preparing copper phthalocyanine pigments of the α-modificationHOECHST AG·Filed 1975·Granted Nov 1, 1977·6 cites·3 claims
- 2759US4758664AProcess for the preparation of linear quinacridonesHOECHST AG·Filed 1986·Granted Jul 19, 1988·6 cites·11 claims
- 2859US4010180AProcess for the purification of copper phthalocyanineHOECHST AG·Filed 1973·Granted Mar 1, 1977·4 cites·6 claims
- 2957US4229583AProcess for preparing thio-indigo dyestuffsHOECHST AG·Filed 1978·Granted Oct 21, 1980·3 cites·6 claims
- 3057US4009180AContinuous process for preparing copper phthalocyanineHOECHST AG·Filed 1973·Granted Feb 22, 1977·4 cites·4 claims
- 3155US3984433AProcess for preparing copper phthalocyanine pigments of the α-modificationHOECHST AG·Filed 1973·Granted Oct 5, 1976·13 cites·4 claims
- 3253US4650879AProcess for the preparation of perylene-3,4,9,10-tetracarboxylic dianhydrideHOECHST AG·Filed 1986·Granted Mar 17, 1987·4 cites·2 claims
- 3348US4732618APowdered pigments with improved rheological properties, processes for their preparation and their use with a content of at least 5% of unsubstituted quinacridoneHOECHST AG·Filed 1985·Granted Mar 22, 1988·11 cites·8 claims
- 3446US4284789AThio-indigo dyestuffsHOECHST AG·Filed 1980·Granted Aug 18, 1981·2 cites·2 claims
- 3545US4693753APigments of the quinacridonequinone series, process for their preparation and their useHOECHST AG·Filed 1986·Granted Sep 15, 1987·3 cites·5 claims
- 3645US4599431AProcess for the preparation of naphthalene-1,4,5,8-tetracarboxylic acid and its 1,8-monoanhydride in a high degree of purityHOECHST AG·Filed 1984·Granted Jul 8, 1986·2 cites·8 claims
- 3745US4460410AProcess for the manufacture of a perylene tetracarboxylic acid dianhydride pigmentHOECHST AG·Filed 1982·Granted Jul 17, 1984·2 cites·13 claims
- 3838US4617403AProcess for preparing a pigment based on 4,4',7,7'-tetrachlorothioindigoHOECHST AG·Filed 1984·Granted Oct 14, 1986·1 cites·5 claims
- 3937US4689087AProcess for the preparation of an organic pigment on the basis of 4,4',7,7'-tetrachloro-thio-indigoHOECHST AG·Filed 1985·Granted Aug 25, 1987·1 cites·5 claims
- 4037US4684753AProcess for preparing 1,3,6,8-tetrabromopyreneHOECHST AG·Filed 1986·Granted Aug 4, 1987·1 cites·7 claims
- 4135US4456762AProcess for the preparation of 4,7-dichloro-3-hydroxy-thionaphtheneHOECHST AG·Filed 1982·Granted Jun 26, 1984·0 cites·6 claims
- 4233US3974177AProcess for the purification of crude polyhalo copper phthalocyaninesHOECHST AG·Filed 1975·Granted Aug 10, 1976·1 cites·8 claims
- 4332US4614803AProcess for the preparation of dry alkali metal salts of 1,8-naphthalimideHOECHST AG·Filed 1985·Granted Sep 30, 1986·0 cites·7 claims
Join the waitlist — get patent alerts
Get an alert when Ernst Spietschka files or is granted a new patent.
We store only your email — no account needed. See our privacy policy.
Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →