Patents by Inventor Masaomi Sasaki

Masaomi Sasaki 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: 4965157
    Abstract: Polyolefin derivatives, which are useful not only as the photoconductive materials for electrophotography, but also as a charge transporting material employed in a function-separating type photoconductor which uses an organic or inorganic pigment as a charge generating material, and an electrophotographic photoconductor containing at least one of the above polyolefin derivatives in a photoconductive layer thereof, are disclosed.
    Type: Grant
    Filed: September 16, 1990
    Date of Patent: October 23, 1990
    Assignees: Ricoh Company, Ltd., Hodogaya Chemical Company, Ltd.
    Inventors: Mitsuru Hashimoto, Tomoyuki Shimada, Nobuo Suzuki, Takayuki Sakai, Susumu Suzuka, Masaomi Sasaki
  • Patent number: 4959290
    Abstract: Indenylidene compounds, which are useful not only as the photoconductive material for electrophotography, but also as a charge transporting material employed in a function-separating type photoconductor in which an organic or inorganic pigment is used as a charge generating material, and an electrophotographic photoconductor containing at least one of the above indenylidene compounds in a photoconductive layer thereof, are disclosed.
    Type: Grant
    Filed: December 8, 1988
    Date of Patent: September 25, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Tamotsu Aruga, Masaomi Sasaki, Mitsuru Hashimoto
  • Patent number: 4957838
    Abstract: An electrophotographic photoconductor is disclosed, which comprises an electroconductive support and a photoconductive layer formed thereon comprising as an effective component at least one triphenylamine compound represented by the following formula (I): ##STR1## wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 each represent hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, or a halogen, which may be the same or different. Further, novel triphenylamine compounds for use in the electrophotographic photoconductor are disclosed.
    Type: Grant
    Filed: September 29, 1989
    Date of Patent: September 18, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Tamotsu Aruga, Masaomi Sasaki, Tomoyuki Shimada
  • Patent number: 4931350
    Abstract: An electrophotographic photoconductor is disclosed, which comprises an electroconductive support and a photoconductive layer formed thereon comprising at least one amino compound of the formula: ##STR1## wherein A represents a substituted or unsubstituted aromatic hydrocarbon group; R.sup.1 and R.sup.2 each represent hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group; Ar represents a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted heterocyclic ring; R.sup.3 and R.sup.4 each represent a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, and n is an integer of 0, 1 or 2.
    Type: Grant
    Filed: October 18, 1988
    Date of Patent: June 5, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Masaomi Sasaki, Mitsuru Hashimoto
  • Patent number: 4916039
    Abstract: An electrophotographic photoconductor is disclosed which comprises an electroconductive support and a photoconductive layer formed thereon, which photoconductive layer comprises as a charge generating material an azo pigment having general formula (I): ##STR1## wherein R.sup.1, R.sup.2, X, A and n are respectively defined in the specification.
    Type: Grant
    Filed: July 8, 1988
    Date of Patent: April 10, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuru Hashimoto, Masaomi Sasaki
  • Patent number: 4898800
    Abstract: Charge transporting materials containing compounds having the formula (I): ##STR1## wherein R.sup.1 represents hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a thioalkoxy group, an aryloxy group, a methylenedioxy group, an aralkyl group, a nitro group, or an unsubstituted or substituted aryl group; R.sup.2 represents hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, halogen; and R.sup.3 and R.sup.4 each represent hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, halogen, a dialkylamino group, an amino group, a thioalkoxy group, an aryloxy group, a methylenedioxy group, an aralkyl group, or an unsubstituted or substituted aryl group, k, m and n each represent an integer of 0 to 5, and l represents an integer of 0 to 4, provided that R.sup.1, R.sup.2, R.sup.3 and R.sup.4 cannot be hydrogen at the same time.
    Type: Grant
    Filed: October 20, 1988
    Date of Patent: February 6, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Masaomi Sasaki, Mitsuru Hashimoto, Tamotsu Aruga
  • Patent number: 4892949
    Abstract: An electrophotograhic photoconductor is disclosed which comprises an electroconductive support material and a photosensitive layer comprising at least one of the stilbene compounds of the formula ##STR1## wherein R.sup.1 represents hydrogen or ##STR2## R.sup.2 represents hydrogen, an alkyl group or a substituted or unsubstituted phenyl group; A represents ##STR3## when R.sup.1 is hydrogen; while when R.sup.1 is ##STR4## A represents ##STR5## a 9-anthryl group or a substituted or unsubstituted N-alkylcarbazolyl group, wherein R.sup.3 represents hydrogen, an alkyl group, an alkoxy group, a halogen or a substituted amino group represented by ##STR6## in which R.sup.4 and R.sup.5 independently represent an alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R.sup.4 and R.sup.5 may form a ring in combination, and m is an integer of 0 through 3 and n is an integer of 0 or 1, provided that, when R.sup.1 is hydrogen and n=0, A is ##STR7## in which R.sup.
    Type: Grant
    Filed: August 9, 1988
    Date of Patent: January 9, 1990
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaomi Sasaki
  • Patent number: 4886846
    Abstract: Aromatic diolefinic compounds including 1,4-divinylbenzene derivatives, which are useful not only as organic photoconductive materials for electrophotography, but also as intermediates for producing diethyl aromatic compounds which are also useful as organic photoconductive materials for electrophotography, the aromatic diethyl compounds, an electrophotographic photoconductor containing any of the above aromatic diethyl compounds in a photosensitve layer thereof, and a charge transporting medium containing any of the aromatic diethyl compound are disclosed.
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: December 12, 1989
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Masaomi Sasaki, Mitsuru Hashimoto
  • Patent number: 4859556
    Abstract: An electrophotographic photoconductor is disclosed which comprises an electroconductive support material and a photosensitive layer comprising at least one of the stilbene compounds of the formula ##STR1## wherein R.sup.1 represents hydrogen or ##STR2## R.sup.2 represents hydrogen, an alkyl group or a substituted or unsubstituted phenyl group; A represents ##STR3## when R.sup.1 is hydrogen; while, when R.sup.1 is ##STR4## A represents ##STR5## a 9-anthryl group or a substituted or unsubstituted N-alkylcarbazolyl group, wherein R.sup.3 represents hydrogen, an alkyl group, an alkoxy group, a halogen or a substituted amino group represented by ##STR6## in which R.sup.4 and R.sup.5 independently represent an alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aralkyl group, and R.sup.4 and R.sup.5 may form a ring in combination, and m is an integer of 0 through 3 and n is an integer of 0 or 1, provided that, when R.sup.1 is hydrogen and n=0, A is ##STR7## in which R.sup.
    Type: Grant
    Filed: August 9, 1988
    Date of Patent: August 22, 1989
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaomi Sasaki
  • Patent number: 4830943
    Abstract: A bisazo compound of the general formula: ##STR1## where Ar is selected from the group consisting of substituents (a).about.(i), ##STR2## a dinitro compound, a diamino compound, and a tetrazonium salt, which respectively serve as a starting material, a first intermediate and a second intermediate for producing the above bisazo compound are prepared, and an electrophotographic photoconductor comprising an electroconductive support having thereon a photoconductive layer containing any of the above bisazo compounds is disclosed.
    Type: Grant
    Filed: May 13, 1987
    Date of Patent: May 16, 1989
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaomi Sasaki, Tomoyuki Shimada
  • Patent number: 4777296
    Abstract: Styryl derivatives of the formula ##STR1## and an electrophotographic photoconductor comprising an electroconductive support material and a photosensitive layer comprising at least one styryl derivative of the same formula are disclosed, in which R.sup.1 is selected from the group consisting of an alkyl group, a substituted alkyl group, an aryl group and substituted aryl group; R.sup.2 is selected from the group consisting of hydrogen, an alkyl group, a substituted alkyl group, an aryl group and a substituted aryl group; and Ar represents an aryl group or a substituted aryl group.
    Type: Grant
    Filed: April 29, 1986
    Date of Patent: October 11, 1988
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaomi Sasaki
  • Patent number: 4709096
    Abstract: Stilbene derivatives of the formula (I) ##STR1## and distyryl derivatives of the formula (II), ##STR2## as defined in the specification, and an electrophotographic photoconductor comprising an electroconductive support material and a photosensitive layer overlayed thereon comprising at least one of the above derivatives, are disclosed.
    Type: Grant
    Filed: February 22, 1985
    Date of Patent: November 24, 1987
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaomi Sasaki
  • Patent number: 4672149
    Abstract: The present invention relates to a photoelectric transducer element comprising a light-transmissive front electrode, a photo-active layer and a back electrode, characterized in that said photo-active layer contains an azo compound expressed by the general formula (I), ##STR1## wherein A represents a coupler residue.
    Type: Grant
    Filed: January 3, 1986
    Date of Patent: June 9, 1987
    Assignee: Ricoh Co., Ltd.
    Inventors: Masao Yoshikawa, Akio Kojima, Tetsuro Suzuki, Masaomi Sasaki
  • Patent number: 4620875
    Abstract: An aqueous ink composition is disclosed, which comprises at least: (1) 0.5 to 30 parts by weight of a dye having the formula of ##STR1## wherein R.sup.1 and R.sup.2 each represent hydrogen, an alkyl group, a phenyl group, an acyl group an acetyl group or a phenylsulfonyl group, R.sup.3 and R.sup.4 each represent hydrogen, an alkyl group, an alkoxy group, halogen, a sulfonic acid group, X represents hydrogen, Na, K, Li or an organic amine cation, m is an integer of 0 or 1; and when m is an integer of 0, n is an integer of 1, and Ar.sup.1 and Ar.sup.2 each represent a substituted phenyl group, a substituted naphthyl group or (R.sup.6 represents an alkyl group, a phenyl group, a substituted phenyl group, a cyano group, an alkoxy group, a carboxyl group or a carbamoyl group, and R.sup.7 represents a substituted phenyl group or a substituted naphthyl group) and when m is an integer of 1, n is an integer of 1 or 2 and Ar.sup.1 and Ar.sup.
    Type: Grant
    Filed: April 3, 1985
    Date of Patent: November 4, 1986
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaru Shimada, Masaomi Sasaki
  • Patent number: 4606988
    Abstract: Styryl derivatives of the formula ##STR1## an electrophotographic photoconductor comprising an electroconductive support material and a photosensitive layer comprising at least one styryl derivative of the same formula are disclosed, in which R.sup.1 is selected from the group consisting of an alkyl group, a substituted alkyl group, an aryl group and substituted aryl group; R.sup.2 is selected from the group consisting of hydrogen, an alkyl group, a substituted alkyl group, an aryl group and a substituted aryl group; and Ar represents an aryl group or a substituted aryl group.
    Type: Grant
    Filed: February 15, 1985
    Date of Patent: August 19, 1986
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaomi Sasaki
  • Patent number: 4603097
    Abstract: Styrene derivatives of the formula ##STR1## and an electrophotographic photoconductor comprising an electroconductive support material and a photosensitive layer comprising at least one styrene derivatives of the same formula are disclosed, in which Ar represents an unsubstituted of substituted phenyl group or an unsubstituted or substituted styryl group, R represents hydrogen, a lower alkyl group or an unsubstituted or substituted phenyl group, and A is selected from the group consisting of ##STR2## wherein R.sup.1 represents a lower alkyl group or a lower alkoxy group, R.sup.2 and R.sup.3 each represent a lower alkyl group, an aralkyl group, or an unsubstituted or substituted phenyl group.
    Type: Grant
    Filed: August 31, 1984
    Date of Patent: July 29, 1986
    Assignee: Ricoh Company, Limited
    Inventors: Masayuki Shoshi, Masaomi Sasaki
  • Patent number: 4596754
    Abstract: An electrophotographic printing original plate is disclosed, which comprises an electroconductive support material and an electrophotographic photosensitive layer formed thereon, which electrophotographic photosensitive layer comprises (i) a charge generation layer consisting essentially of a particular azo pigment serving as a charge generating material and (ii) a charge transport layer consisting essentially of a charge transporting material and an alkali-soluble resin; and an electrophotographic printing plate making process using the above printing original plate is also disclosed, which comprises the steps of electrically charging uniformly the above printing original plate, exposing the charged printing original plate to optical images to form latent electrostatic images thereon, developing the latent electrostatic images with toner, fixing the toner images to the printing original plate, and removing the electrophotographic photosensitive layer portions corresponding to the non-image areas of the print
    Type: Grant
    Filed: April 23, 1985
    Date of Patent: June 24, 1986
    Assignee: Ricoh Company, Ltd.
    Inventors: Kyoji Tsutsui, Mitsuru Hashimoto, Masafumi Ohta, Masaomi Sasaki
  • Patent number: 4572884
    Abstract: Stilbene derivatives of the formula ##STR1## and an electrophotographic photoconductor comprising an electroconductive support material and a photosensitive layer comprising at least one stilbene derivative of the same formula are disclosed, in which R.sup.1 represents a lower alkyl group, an alkoxy group or an unsubstituted or substituted phenoxy group or a hydroxyl group, R.sup.2 represents hydrogen, a lower alkyl group or an unsubstituted or substituted phenyl group, Ar represents ##STR2## or a 9-anthryl group, R.sup.3 represents hydrogen, an alkyl group, an alkoxy group halogen or substituted amino group represented by ##STR3## (in which R.sup.4 and R.sup.5 each represent an alkyl group, an unsubstituted or substituted aralkyl group, or an unsubstituted of substituted aryl group), m is an integer of 0, 1, 2 or 3, and n is an integer of 0 or 1.
    Type: Grant
    Filed: November 22, 1983
    Date of Patent: February 25, 1986
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaomi Sasaki
  • Patent number: 4567124
    Abstract: The present invention provides an multilayer type electrophotographic element comprising laminating a charge generating layer containing a trisazo pigment represented by the general formula (1) on an electrically conductive substrate: ##STR1## (wherein, R denotes ##STR2## and laminating a charge transfer layer containing an .alpha.-substituted stilbene compound represented by the general formula (2): ##STR3## (wherein, R.sup.1 denotes a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, R.sup.2, R.sup.3, and R.sup.4 each denotes a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group, and Ar.sup.2 denotes a substituted or unsubstituted arylene group. Ar.sup.1 and R.sup.1 may be combined to form a ring. n is an integer of 0 or 1) and a resinous binder, on the charge generating layer.
    Type: Grant
    Filed: November 9, 1984
    Date of Patent: January 28, 1986
    Assignee: Ricoh Co., Ltd.
    Inventors: Masafumi Ohta, Masaomi Sasaki, Masayuki Shoshi
  • Patent number: 4515883
    Abstract: Stilbene derivatives of the formula (I) ##STR1## and distyryl derivatives of the formula (II), ##STR2## as defined in the specification, and an electrophotographic photoconductor comprising an electroconductive support material and a photosensitive layer overlayed thereon comprising at least one of the above derivatives, are disclosed.
    Type: Grant
    Filed: March 30, 1984
    Date of Patent: May 7, 1985
    Assignee: Ricoh Company, Ltd.
    Inventor: Masaomi Sasaki