1
Takeo Kazami, Kiyoshi Sakai, Mitsuru Hashimoto, Masaomi Sasaki, Kyoji Tsutsui, Masafumi Ohta: Electrophotographic element having charge transport layer. Ricoh, Blanchard Flynn Thiel Boutell & Tanis, January 13, 1981: US04245021 (53 worldwide citation)

An electrophotographic element according to the present invention exhibits an exceedingly high sensitivity and it comprises (1) an electroconductive support, a charge producing layer consisting essentially of a charge producing substance and a charge transport layer consisting essentially of a charg ...


2
Masao Yoshikawa, Masayuki Shoshi, Tetsuro Suzuki, Masakatsu Shimoda, Kaoru Teramura, Megumi Kawahara, Akio Kojima, Masaomi Sasaki, Masafumi Ohta: Positively-chargeable single-layered type electrophotographic photoconductor. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt, February 20, 1996: US05492784 (53 worldwide citation)

A positively-chargeable single-layered type organic electrophotographic photoconductor composed of an electroconductive support and an organic single-layered photoconductive layer containing a charge generating material, an organic positive hole transporting material and an organic acceptor compound ...


3
Teruyuki Ohnuma, Tomoyuki Shimada, Masafumi Ohta, Fumio Kawamura, Yohta Sakon, Toshihiko Takahashi: Electroluminescent device. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt, October 6, 1992: US05153073 (46 worldwide citation)

Disclosed herein is an electroluminescent device comprising an anode and a cathode and one or plurality of organic compound layer sandwiched therebetween, at least one of the organic compound layers being composed of an organic compound represented by the general formula (I): ##STR1## (wherein A.sup ...


4
Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai: Electroluminescent device comprising oxadiazole compounds luminescent material, oxadiazole compounds for the device, and method of producing oxadiazole compounds. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt, May 30, 1995: US05420288 (44 worldwide citation)

An electroluminescent device is composed of a negative electrode, a positive electrode, and an organic compound layer which is interposed between the negative electrode and the positive electrode and includes at least one oxadiazole compound with a plurality of aryl oxadiazole structures. Novel oxad ...


5
Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai: Electroluminescent device comprising oxadiazole compounds luminescent material, oxadiazole compounds for the device, and method of producing oxadiazole compounds. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt P C, August 12, 1997: US05656401 (40 worldwide citation)

An electroluminescent device is composed of a negative electrode, a positive electrode, and an organic compound layer which is interposed between the negative electrode and the positive electrode and includes at least one oxadiazole compound with a plurality of aryl oxadiazole structures. Novel oxad ...


6
Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai: Method of producing oxadiazole compounds. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt P C, January 28, 1997: US05597925 (37 worldwide citation)

An electroluminescent device is composed of a negative electrode, a positive electrode, and an organic compound layer which is interposed between the negative electrode and the positive electrode and includes at least one oxadiazole compound with a plurality of aryl oxadiazole structures. Novel oxad ...


7
Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai: Electroluminescent device comprising oxadiazole compounds luminescent material, oxadiazole compounds for the device, and method of producing oxadiazole compounds. Ricoh Company, Oblon Spivak McClelland Maier & Neustadt P C, March 11, 1997: US05610309 (36 worldwide citation)

An electroluminescent device is composed of a negative electrode, a positive electrode, and an organic compound layer which is interposed between the negative electrode and the positive electrode and includes at least one oxadiazole compound with a plurality of aryl oxadiazole structures. Novel oxad ...


8
Akio Kozima, Mitsuru Hashimoto, Masafumi Ohta, Masaomi Sasaki, Zenjiro Okuno: Electrophotographic photosensitive material with electron donors and electron acceptors. Ricoh, Blanchard Flynn Thiel Boutell & Tanis, April 28, 1981: US04264695 (29 worldwide citation)

A photosensitive material for use in electrophotography which comprises a conductive support, a first layer consisting essentially of a substance capable of generating a conductive carrier through light absorption and an electron donor or an electron acceptor, and a second layer consisting essential ...


9
Mitsutoshi Anzai, Akihiro Imai, Masaomi Sasaki, Hiroshi Tamura, Tomoyuki Shimada, Tetsuro Suzuki, Masafumi Ohta: Electrophotographic photoconductor and aromatic polycarbonate resin for use in the same. Ricoh Company, Hodogaya Chemical, Oblon Spivak McClelland Maier & Neustadt P C, May 5, 1998: US05747204 (27 worldwide citation)

An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon, containing a novel aromatic polycarbonate resin having a repeat unit of formula (I): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 each is an alkyl group which may have a substitu ...


10
Tomoyuki Shimada, Masaomi Sasaki, Masafumi Ohta, Akihiro Imai, Mitsutoshi Anzai, Tamotsu Aruga, Kazukiyo Nagai, Katsuhiro Morooka: Electrophotographic photoconductor and aromatic polycarbonate resin for use therein. Ricoh Company, Hodogaya Chemical, Oblon Spivak McClelland Maier & Neustadt P C, February 22, 2000: US06027846 (26 worldwide citation)

An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a structural unit of formula (I), two structural units of formulae (I) and (II), or a repeat unit of for ...