Inventor · disambiguated record
Helmold Von Plessen
Also filed as: VON PLESSEN HELMOLD
14 granted patents·83 citations·filing 1974–1994
90Inventor score
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14 records- 0189US4479924AProcess for the separation of heavy metal compounds from phosphoric acidHOECHST AG·Filed 1983·Granted Oct 30, 1984·31 cites·5 claims
- 0264US4794204AProcess for the removal of dimethyl ether in methyl chlorideHOECHST AG·Filed 1987·Granted Dec 27, 1988·9 cites·2 claims
- 0361US3972987AProcess for regenerating sulfuric acidHOECHST AG·Filed 1974·Granted Aug 3, 1976·10 cites·21 claims
- 0460US4916257AProcess for the purification of 2-hydroxynaphthalene-6-carboxylic acidHOECHST AG·Filed 1989·Granted Apr 10, 1990·6 cites·9 claims
- 0549US4010240AProcess for the regeneration of sulfuric acidHOECHST AG·Filed 1974·Granted Mar 1, 1977·7 cites·10 claims
- 0644US5464876AProcess for the recovery of valuable materials during the work-up of polyvinyl chlorideHOECHST AG·Filed 1994·Granted Nov 7, 1995·8 cites·2 claims
- 0742US4194952AProcess for regenerating waste sulfuric acidERCO IND LTD·Filed 1977·Granted Mar 25, 1980·5 cites·4 claims
- 0834US4925959ADioxane adduct of 2-hydroxynaphthalene-6-carboxylic acid and process for the preparation thereofHOECHST AG·Filed 1989·Granted May 15, 1990·0 cites·1 claims
- 0931US5047558AProcess for the preparation of a dioxane adduct of 2-hydroxynaphthalene-6-carboxylic acidHOECHST AG·Filed 1990·Granted Sep 10, 1991·0 cites·4 claims
- 1030US5308600AProcess for conditioning waste sulfuric acidHOECHST AG·Filed 1991·Granted May 3, 1994·2 cites·19 claims
- 1130US4145393AProcess for the protection against corrosion of cast iron in boiling concentrated sulfuric acidHOECHST AG·Filed 1977·Granted Mar 20, 1979·2 cites·4 claims
- 1228US4150103AFoam prevention during the regeneration of waste sulfuric acid with aromatic nitro compoundsHOECHST AG·Filed 1977·Granted Apr 17, 1979·0 cites·6 claims
- 1328US4148858AProcess for the protection against corrosion of cast iron boilersHOECHST AG·Filed 1977·Granted Apr 10, 1979·0 cites·5 claims
- 1428US4032622AMethod of concentrating sulfuric acid using a boiler of improved cast ironHOECHST AG·Filed 1976·Granted Jun 28, 1977·3 cites·2 claims
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Identity basis: PatentsView inventor disambiguation (2025Q4-odp release). How scoring works →