Inventor · Osaka, JP

Fumio Sugai

26Patents
5h-index
29Co-inventors
69Inventor score

Filing activity: Mar 25, 1994 → Jun 7, 2017

Most-cited inventions

PatentTitleAreaCited byStatus
US5863688A Naphthoquinone derivative Physics 15 Expired
US6127076A Naphthalenetetracarboxylic acid diimide derivatives and photosensitive material for electrophotography Chemistry; Metallurgy 11 Expired
US5994012A Naphthoquinone derivative and electrophotosensitive material using same Physics 10 Expired
US5976742A Naphthoquinone derivative and electrophotographic material using the naphthoquinone derivative Physics 10 Expired
US6174638A Naphthalenetetracarboxylic acid diimide derivatives and photosensitive materials for electrophotography Physics 7 Expired
US5773613A Tryptoanthrinimine derivative and electrophotosensitive material using the same Physics 5 Expired
US5977389A Naphthoquinone derivative Physics 4 Expired
US6346355B2 Electrophotosensitive material Physics 3 Expired
US5468874A Benzothiophene/indole-substituted maleimide derivatives, photochromic material comprising said derivatives and optical recording material using the same material Chemistry; Metallurgy 2 Expired
US5817810A Tryptanthrine compounds Physics 2 Expired
US6500592B2 Electrophotosensitive material Physics 1 Expired
US6395439B1 Naphthoquinone derivative and electrophotosensitive material using the same Physics 1 Expired
US9690217B2 Triarylamine derivative, electrophotographic photosensitive member, and image forming apparatus Physics 1 Active
US9436105B2 Triarylamine derivative and electrophotographic photosensitive member Electricity 1 Active
US10126667B2 Quinone derivative and electrophotographic photosensitive member Physics 0 Active
US9964869B2 Triarylamine derivative, electrophotographic photosensitive member, and method for producing electrophotographic photosensitive member Physics 0 Active
US9447022B2 Triarylamine derivative and electrophotographic photosensitive member Physics 0 Active
US9783493B2 Quinone derivative and electrophotographic photosensitive member Chemistry; Metallurgy 0 Active
US9376371B2 Triphenylamine derivative, method for manufacturing the same, and electrophotographic photosensitive member Physics 0 Active
US9581921B2 Electrophotographic photosensitive member Physics 0 Active
US9494881B2 Triarylamine derivative and electrophotographic photosensitive member Physics 0 Active
US6376142B2 Electrophotosensitive material containing specific maleimide derivative Physics 0 Expired
US9783491B2 Quinone derivative and electrophotographic photosensitive member Physics 0 Active
US7468230B2 Wet-developing electrophotographic photoconductor and wet-developing image Physics 0 Expired
US9454091B2 Hydrazone derivative of triphenylamine and electrophotographic photosensitive member Physics 0 Active

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