Patents by Inventor Chihaya Adachi

Chihaya Adachi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5910561
    Abstract: An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a repeat unit of formula (I), or two repeat units of formulae (II) and (III): ##STR1## wherein Ar.sup.1 to Ar.sup.6, X, n, k and j are as specified in the specification.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: June 8, 1999
    Assignees: Ricoh Company, Ltd., Hodogaya Chemical Co., Ltd.
    Inventors: Chihaya Adachi, Masaomi Sasaki, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Nozomu Tamoto, Akira Katayama, Mitsutoshi Anzai, Akihiro Imai, Katsuhiro Morooka
  • Patent number: 5846680
    Abstract: An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a repeat unit of formula (I), or two repeat units of formulae (II) and (III): ##STR1## wherein Ar.sup.1 to Ar.sup.6, X, n, k and j are as specified in the specification.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: December 8, 1998
    Assignees: Ricoh Company, Ltd., Hodogaya Chemical Co., Ltd.
    Inventors: Chihaya Adachi, Masaomi Sasaki, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Nozomu Tamoto, Akira Katayama, Mitsutoshi Anzai, Akihiro Imai, Katsuhiro Morooka
  • Patent number: 5840454
    Abstract: An aromatic polycarbonate containing a structural unit of the formula: ##STR1## wherein R.sup.1 is a hydrogen atom, a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, Ar.sup.1 is a substituted or unsubstituted aryl group and Ar.sup.2 and Ar.sup.3 are independently a substituted or unsubstituted arylene group. The aromatic polycarbonate is capable of transferring charges and is used for forming a photosensitive layer of an electrophotographic photosensitive medium.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: November 24, 1998
    Assignees: Ricoh Company, Ltd., Hodogaya Chemical Co., Ltd.
    Inventors: Kazukiyo Nagai, Masaomi Sasaki, Hiroshi Tamura, Tetsuro Suzuki, Tomoyuki Shimada, Chihaya Adachi, Chiaki Tanaka, Nozomu Tamoto, Kouji Kishida, Akira Katayama, Mitsutoshi Anzai, Akihiro Imai
  • Patent number: 5789128
    Abstract: An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a repeat unit of formula (I), or two repeat units of formulae (II) and (III): ##STR1## wherein Ar.sup.1 to Ar.sup.6, X, n, k and j are as specified in the specification.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: August 4, 1998
    Assignees: Ricoh Company, Ltd., Hodogaya Chemical Co., Ltd.
    Inventors: Chihaya Adachi, Masaomi Sasaki, Kazukiyo Nagai, Tomoyuki Shimada, Chiaki Tanaka, Nozomu Tamoto, Akira Katayama, Mitsutoshi Anzai, Akihiro Imai, Katsuhiro Morooka
  • Patent number: 5723243
    Abstract: An electrophotographic photoconductor includes an electroconductive support, and a photoconductive layer formed thereon containing as an effective component an aromatic polycarbonate resin having a repeat unit of formula (I), or two repeat units of formula (II) and formula (III): ##STR1## wherein n, Ar.sup.1, Ar.sup.2, Ar.sup.3, R.sup.1, R.sup.2 and X are as specified in the specification, ##STR2## wherein k and j are also as specified in the specification.
    Type: Grant
    Filed: May 16, 1996
    Date of Patent: March 3, 1998
    Assignees: Ricoh Company, Ltd., Hodogaya Chemical Co., Ltd.
    Inventors: Masaomi Sasaki, Hiroshi Tamura, Tomoyuki Shimada, Tetsuro Suzuki, Chiaki Tanaka, Kouji Kishida, Akira Katayama, Kazukiyo Nagai, Chihaya Adachi, Nozomu Tamoto, Mitsutoshi Anzai, Akihiro Imai
  • Patent number: 5709959
    Abstract: An organic thin film electroluminescence (EL) device having an organic light emitting layer consisting of an organic substance placed between an anode and a cathode which face each other is provided, in which the ionization potential (Ip) of the anode satisfies the formula: Ip>5.0 eV.
    Type: Grant
    Filed: September 18, 1995
    Date of Patent: January 20, 1998
    Assignee: Ricoh Company, Ltd.
    Inventors: Chihaya Adachi, Kazukiyo Nagai, Nozomu Tamoto
  • Patent number: 5702833
    Abstract: An organic electroluminescent element having an anode, a cathode, and an organic compound layer provided between the electrodes, the organic compound layer containing an oxadiazole compound of formula (I) or (II): ##STR1## wherein A.sup.1 to A.sup.6 are each an aromatic hydrocarbon group or an aromatic heterocyclic group which may have a substituent; X is a hydrogen atom or a fluorine atom; R.sup.1 and R.sup.2 are each a hydrogen atom, a halogen atom, or an alkyl group which may have a substituent, or an alkoxyl group which may have a substituent; and R.sup.3, R.sup.4 and R.sup.5 are each a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, or hydroxyl group.
    Type: Grant
    Filed: August 14, 1995
    Date of Patent: December 30, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazukiyo Nagai, Chihaya Adachi, Nozomu Tamoto, Yohta Sakon
  • Patent number: 5656401
    Abstract: 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 oxadiazole compounds for use in the electroluminescent device and a method of producing the oxadiazole compounds are disclosed.
    Type: Grant
    Filed: October 12, 1994
    Date of Patent: August 12, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai
  • Patent number: 5610309
    Abstract: 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 oxadiazole compounds for use in the electroluminescent device and a method of producing the oxadiazole compounds are disclosed.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 11, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai
  • Patent number: 5597925
    Abstract: 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 oxadiazole compounds for use in the electroluminescent device and a method of producing the oxadiazole compounds are disclosed.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 28, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai
  • Patent number: 5420288
    Abstract: 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 oxadiazole compounds for use in the electroluminescent device and a method of producing the oxadiazole compounds are disclosed.
    Type: Grant
    Filed: April 14, 1993
    Date of Patent: May 30, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Masafumi Ohta, Yohta Sakon, Toshihiko Takahashi, Chihaya Adachi, Kazukiyo Nagai
  • Patent number: 5382477
    Abstract: There is disclosed an EL element having at least one layer made from organic materials between an electron injection electrode and a hole injection electrode, the organic materials consisting of oxadiazole series compounds which have a plurality of oxadiazole rings.
    Type: Grant
    Filed: February 24, 1992
    Date of Patent: January 17, 1995
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Shogo Saito, Tetsuo Tsutsui, Chihaya Adachi, Yuji Hamada
  • Patent number: 5085947
    Abstract: An electroluminescence device containing a first organic compound having positive-hole-transporting and luminous properties, such as a triphenyl amine compound, a stilbene derivative or a pyrazoline derivative, and a second organic compound having electron-transporting property, such as an oxadiazole derivative, in its luminescence layer interposed between a pair of electrodes.
    Type: Grant
    Filed: December 29, 1989
    Date of Patent: February 4, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Shogo Saito, Tetsuo Tsutui, Chihaya Adachi
  • Patent number: 5085946
    Abstract: An electroluminesence device comprising an organic compound having positive-hole-transporting property and a fluorescent organic compound having electron-transporting property in its luminescence layer interposed between a pair of electrodes. When the electroluminescence device comprises a cyclopentadiene derivative having formula (I) as the fluorescent organic compound, the device can emit blue light which has not been attained so far: ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 each independently represent hydrogen, an alkyl group having 1 to 10 carbon atoms, which may have a substituent, an alicyclic group having 5 to 6 carbon atoms, an alkoxyl group having 1 to 6 carbon atoms, which may have a substituent, a halogen, an acyl group, a hydroxyl group, an aryloxy group, an aryl group which may have a substituent, an allyl group, or an aldehyde group.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: February 4, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Shogo Saito, Tetsuo Tsutsui, Chihaya Adachi
  • Patent number: 5077142
    Abstract: Disclosed herein an electroluminescent device for converting an energy of an electric field applied directly to a light energy and capable of producing surface luminescent for a large area different from conventional incandescent lamps, fluorescent lamps or light emitting diodes.
    Type: Grant
    Filed: April 19, 1990
    Date of Patent: December 31, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Yohta Sakon, Teruyuki Ohnuma, Mitsuru Hashimoto, Shogo Saito, Tetsuo Tsutsui, Chihaya Adachi
  • Patent number: 5059863
    Abstract: An organic electroluminescent device having an organic hole injection transport layer and an organic luminescent layer formed between two conductive layers constituting electrodes, wherein the organic luminescent layer contains a compound selected from the group consisting of a compound of the following formula (I): ##STR1## wherein each of A and B is an aromatic hydrocarbon group which may have a substituent, C is a nitrogen atom which may have a substituent, a sulfur atom, an oxygen atom, or a selenium atom, and D is a nitrogen atom, or a carbon atom which may have a substituent; a compound of the following formula (II): ##STR2## wherein each of E, F, G and .circle.
    Type: Grant
    Filed: July 3, 1990
    Date of Patent: October 22, 1991
    Assignee: Mitsubishi Kasei Corporation
    Inventors: Masashi Tashiro, Shuntaro Mataga, Kazufumi Takahashi, Shogo Saito, Tetsuo Tsutsui, Chihaya Adachi, Yoshiharu Sato, Shuichi Maeda