Inventor · Willich, DE

Gerhard Fennhoff

31Patents
8h-index
61Co-inventors
74Inventor score

Filing activity: Jan 15, 1991 → Aug 28, 2002

Most-cited inventions

PatentTitleAreaCited byStatus
US5410014A Method of preparing aliphatic-aromatic polycarbonates Chemistry; Metallurgy 33 Expired
US5302774A Process for the production of bisphenols Chemistry; Metallurgy 30 Expired
US5914431A Cocatalysts for the synthesis of bisphenols Chemistry; Metallurgy 28 Expired
US5698600A Process for the production of bisphenols with the use of new cocatalysts Chemistry; Metallurgy 27 Expired
US5780690A Bisphenol synthesis on modified ion-exchange resins using specially purified carbonyl compounds Chemistry; Metallurgy 22 Expired
US6211417A Process for preparing bis-(4-hydroxyaryl) alkanes Chemistry; Metallurgy 20 Expired
US5214072A Purification of polycarbonate, polyester carbonate or polyester waste Emerging Cross-Sectional Technologies 10 Expired
US6288284A Method for producing bis(4-hydroxyaryl)alkanes Emerging Cross-Sectional Technologies 9 Expired
US5151452A Purification of polycarbonate and polyester carbonate waste Emerging Cross-Sectional Technologies 8 Expired
US6307111A Method for continuous production of dihydroxydiarylalkanes Emerging Cross-Sectional Technologies 8 Expired
US5382605A Polycondensates which can be sterilized by .gamma.-radiation Chemistry; Metallurgy 7 Expired
US5357028A Method of preparing polycarbonates and polyester carbonates Chemistry; Metallurgy 6 Expired
US6191316A Method for processing mother liquors from the production of bisphenol Emerging Cross-Sectional Technologies 6 Expired
US6723881B1 Method for conditioning ion exchangers Performing Operations; Transporting 6 Expired
US5393835A Polycarbonate/ABS molding compounds Chemistry; Metallurgy 6 Expired
US6486363B1 Process for the manufacture of bis(4-hydroxyaryl)alkanes Chemistry; Metallurgy 5 Expired
US5464893A Radiation-resistant polycarbonates Chemistry; Metallurgy 5 Expired
US5612398A Radiation-resistant polycarbonates Chemistry; Metallurgy 5 Expired
US5684062A (Co)polycarbonates stabilised against .gamma.-radiation Chemistry; Metallurgy 5 Expired
US5420241A Process for the purification of polycarbonate and polyester carbonate solutions Chemistry; Metallurgy 3 Expired
US5288923A Preparation of ethers of diphenols Chemistry; Metallurgy 3 Expired
US5376715A Heat stabilization or aromatic polycarbonates Chemistry; Metallurgy 3 Expired
US5773491A (Co)polycarbonates stabilized against .gamma.-radiation Chemistry; Metallurgy 3 Expired
US5408027A Process for the production of aliphatic-aromatic polycarbonates Chemistry; Metallurgy 2 Expired
US5399600A Stabilized, flame resistant polycarbonate moulding compounds Chemistry; Metallurgy 2 Expired

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