Thomas A. Johnson
30Patents
14h-index
17Co-inventors
78Inventor score
Filing activity: May 14, 1979 → Sep 11, 2000
Most-cited inventions
| Patent | Title | Area | Cited by | Status |
|---|---|---|---|---|
| US4316840A | Reforming linear polyamines | Chemistry; Metallurgy | 38 | Expired |
| US4578517A | Polyalkylene polyamines from alkanolamine and ammonia or amines using group IIIB metal acid phosphate catalysts | Chemistry; Metallurgy | 37 | Expired |
| US4314083A | Preparation of linear polyalkylene polyamines | Chemistry; Metallurgy | 29 | Expired |
| US4394524A | Preparation of polyalkylene polyamines from ammonia, alkyleneamine, and alkanolamine | Emerging Cross-Sectional Technologies | 28 | Expired |
| US4316841A | Reforming linear polyamines | Chemistry; Metallurgy | 27 | Expired |
| US4463193A | Production of noncyclic polyalkylene polyamines | Human Necessities | 22 | Expired |
| US4560798A | Production of aminoethylethanolamine using rare earth metal or strontium hydrogen phosphates as catalysts | Performing Operations; Transporting | 21 | Expired |
| US4605770A | Noncyclic polyalkylene polyamines by the reaction of an alkanolamine compound and an alkyleneamine compound in the presence of a Group IIA or Group IIIB metal acid phosphate catalyst | Chemistry; Metallurgy | 20 | Expired |
| US5869653A | Hydrogenation of nitriles to produce amines | Chemistry; Metallurgy | 20 | Expired |
| US4503253A | Production of noncyclic polyalkyene polyamines | Chemistry; Metallurgy | 19 | Expired |
| US4617418A | Polyalkylene polyamines via vapor phase reaction | Chemistry; Metallurgy | 19 | Expired |
| US4720588A | Polyalkylene polyamines via vapor phase reaction using inert gas | Chemistry; Metallurgy | 18 | Expired |
| US4362886A | Preparation of linear polyalkylene polyamines using metal catalyst | Chemistry; Metallurgy | 15 | Expired |
| US4918233A | Production of ethylenediamine from monoethanolamine and ammonia | Chemistry; Metallurgy | 15 | Expired |
| US4399308A | Lewis acid halide catalysts for preparation of polyamines | Chemistry; Metallurgy | 14 | Expired |
| US4224249A | Toluene diamine from non-washed dinitrotoluene | Chemistry; Metallurgy | 14 | Expired |
| US4766247A | Color reduction of polyamines by mild catalytic hydrogenation | Chemistry; Metallurgy | 12 | Expired |
| US5075507A | Process for the preparation of bis(aminopropyl)aliphatic glycols | Chemistry; Metallurgy | 9 | Expired |
| US6395188B1 | Treatment of water containing organic wastes with ammonium nitrate | Emerging Cross-Sectional Technologies | 9 | Expired |
| US4990672A | Propylene-linked polyethylene polyamines and a process for making same | Chemistry; Metallurgy | 7 | Expired |
| US6332986A | Treatment of water containing organic wastes with ammonium nitrate | Emerging Cross-Sectional Technologies | 6 | Expired |
| US4597911A | Production of amino aliphatic and cycloaliphatic hydrogen sulfates | Chemistry; Metallurgy | 4 | Expired |
| US5769959A | Process for removing insoluable N-vinyl amide polymer from equipment | Chemistry; Metallurgy | 4 | Expired |
| US5081305A | Process for the preparation of bis(aminopropoxy)alkanes | Emerging Cross-Sectional Technologies | 3 | Expired |
| US4709028A | Synthesis of heterocyclic amines via the reaction of dialkylene glycol and ammonia | Chemistry; Metallurgy | 2 | Expired |
Source: USPTO / EPO open patent data. Inventor disambiguation is heuristic; counts are objective bibliographic measures.