Patents by Inventor Tamotsu Aruga

Tamotsu Aruga 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: 5248826
    Abstract: An electrophotographic photoconductor comprising an electroconductive support and a photoconductive layer formed thereon comprising as an effective component at least one polyether compound represented by formula (I): ##STR1## wherein Ar represents a phenylene group or a biphenylene group; R.sup.1 and R.sup.2 each represent an alkyl group which may have a substituent, or an aryl group which may have a substituent; and n is an integer of 1 to 4. Furthermore, charge transporting material comprising the above polyether compound, polyether compounds having formula (II) for use in the electrophotographic photoconductor and a method of preparing the same are disclosed, ##STR2## wherein m is an integer of 1 or 2.
    Type: Grant
    Filed: July 29, 1992
    Date of Patent: September 28, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaomi Sasaki, Tamotsu Aruga, Tomoyuki Shimada
  • Patent number: 5233090
    Abstract: [2,2]paracyclophane compounds having formula (I): ##STR1## wherein R.sup.1 and R.sup.2 independently represent an alkyl group having 1 to 4 carbon atoms, which may have a substituent, or an aryl group which may have a substituent, provided that R.sup.1 and R.sup.2 may not be a methyl group at the same time, and methods of producing the same are disclosed. These compounds are useful as an effective photoconductive component for an electrophotographic photoconductor which is composed of an electroconductive support and a photoconductive layer formed thereon.
    Type: Grant
    Filed: November 6, 1991
    Date of Patent: August 3, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Masaomi Sasaki, Tamotsu Aruga
  • Patent number: 5219692
    Abstract: An electrophotographic photoconductor comprising an electroconductive support, and a photoconductive layer formed thereon comprising at least one tertiary amine compound having a condensed polycyclic hydrocarbon group of formula (I): ##STR1## wherein A.sup.1 and A.sup.2 each independently represent an unsubstituted or substituted alkyl group or aryl group, and Ar represents an unsubstituted or substituted condensed polycyclic hydrocarbon group. Furthermore, novel tertiary amine compounds having a condensed polycyclic hydrocarbon group are disclosed.
    Type: Grant
    Filed: March 8, 1990
    Date of Patent: June 15, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Masaomi Sasaki, Tamotsu Aruga
  • Patent number: 5158850
    Abstract: An electrophotographic photoconductor comprising an electroconductive support and a photoconductive layer formed thereon comprising as an effective component at least one polyether compound represented by formula (I): ##STR1## wherein Ar represents a phenylene group or a biphenylene group; R.sup.1 and R.sup.2 each represent an alkyl group which may have a substituent, or an aryl group which may have a substituent; and n is an integer of 1 to 4. Furthermore, charge transporting material comprising the above polyether compound, polyether compounds having formula (II) for use in the electrophotographic photoconductor and a method of preparing the same are disclosed, ##STR2## wherein m is an integer of 1 or 2.
    Type: Grant
    Filed: December 13, 1990
    Date of Patent: October 27, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaomi Sasaki, Tamotsu Aruga, Tomoyuki Shimada
  • Patent number: 5098807
    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 [2,2]paracyclophane compound formula (I): ##STR1## wherein R.sup.1 and R.sup.2 independently represent an alkyl group having 1 to 4 carbon atoms, which may have a substituent, or an aryl group which may have a substituent; R.sup.3 and R.sup.4 each represent hydrogen, an alkyl group having 1 to 4 carbon atoms, an alkoxyl group having 1 to 4 carbon atoms, or a halogen; and m is an integer of 1 to 3, and n is an integer of 1 to 4, and R.sup.3 and R.sup.4 may be the same or different when m and n are both 2 or more. Furthermore, novel [2,2]paracyclophane compounds for use in the electrophotographic photoconductor and methods of producing the same are disclosed.
    Type: Grant
    Filed: October 31, 1989
    Date of Patent: March 24, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Masaomi Sasaki, Tamotsu Aruga
  • Patent number: 5059708
    Abstract: A pyrene-ring-containing olefin compound of formula [I]: ##STR1## wherein R is a hydrogen atom, an unsubstituted or substituted alkyl group, or an unsubtituted or substituted aryl group; Y is an unsubstituted or substituted aliphatic hydrocarbon group, a cyclic hydrocarbon group, or an aromatic group; and n is an integer of 1 to 3, and when n is 1, Y and R may be bonded to form a ring; an intermediate for producing the above olefin compound, which is a phosphonic acid ester of formula [II]: ##STR2## wherein R.sup.1 is an alkyl group with 1 to 4 carbon atoms; and a method of producing the above olefin compound are disclosed.
    Type: Grant
    Filed: January 16, 1991
    Date of Patent: October 22, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Tamotsu Aruga, Masaomi Sasaki, Tomoyuki Shimada, Hiroshi Adachi
  • Patent number: 5047590
    Abstract: Compounds having formula (I), which are useful as starting or intermediate materials for preparing organic photoconductive materials, or as organic photoconductive materials: ##STR1## wherein R.sup.1 is a nitro group, an amino group or a diphenylamino group which may have a substituent; and R.sup.2 is hydrogen or an alkyl group having 1 to 6 carbon atoms, and methods of preparing the above compounds are disclosed.
    Type: Grant
    Filed: May 29, 1990
    Date of Patent: September 10, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Tomoyuki Shimada, Masaomi Sasaki, Tamotsu Aruga
  • Patent number: 4992350
    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 biphenyl compound represented by the following formula (I): ##STR1## wherein R.sup.1 and R.sup.2 each represent an alkyl group which may have a substituent, an alkoxyl group which may have a substituent, or an aryl group which may have a substituent, provided that at least one of R.sup.1 and R.sup.2 represents an unsubstituted or substituted aryl group. Furthermore, charge transporting materials comprising the above biphenyl compound and novel biphenyl compounds having formula (II) for use in the electrophotographic photoconductor are disclosed.
    Type: Grant
    Filed: September 19, 1989
    Date of Patent: February 12, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaomi Sasaki, Tamotsu Aruga, Tomoyuki Shimada
  • 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: 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: 4793860
    Abstract: An aqueous ink composition comprises (a) a dye having formula (I) in an amount of 0.5 to 6.0 wt. %, in which 20% or more of the total of the cations of --SO.sub.3 X and --OX groups directly connected to the aromatic rings thereof is replaced by Li.sup.+ ion or a quaternary ammonium ion, ##STR1## wherein X represents a cation; R.sup.1 represents hydrogen, a hydroxyl group, an alkyl group having 1 to 4 carbon atoms, or an amino group; R.sup.2 represents ##STR2## (in which R.sup.5 and R.sup.6 each represent hydrogen, an alkyl group having 1 to 4 carbon atoms, a hydroxyethyl group, or a cyanoethyl group); R.sup.3 represents hydrogen, --SO.sub.3 X; R.sup.4 represents hydrogen, or a --C.sub.2 H.sub.4 OX, (b) a polyhydric alcohol in an amount of at least 10 wt. %; and (c) water.
    Type: Grant
    Filed: April 2, 1987
    Date of Patent: December 27, 1988
    Assignee: Ricoh Company, Ltd.
    Inventors: Kakuji Murakami, Masaru Shimada, Tamotsu Aruga, Hiroyuki Uemura, Kiyofumi Nagai
  • Patent number: 4740420
    Abstract: A recording medium for ink-jet printing comprising a support material containing at least in the surface portion thereof a water-soluble metal salt with the ion valence of the metal thereof being 2 to 4 and a cationic organic material.
    Type: Grant
    Filed: June 20, 1986
    Date of Patent: April 26, 1988
    Assignee: Ricoh Company, Ltd.
    Inventors: Eiichi Akutsu, Tadashi Fujii, Kakuji Murakami, Tamotsu Aruga
  • Patent number: 4737190
    Abstract: An aqueous ink composition for ink-jet recording comprising an aqueous solution of a water-soluble dye of formula (I) and a humectant dissolved in water: ##STR1## wherein R.sup.1 and R.sup.2 each represent hydrogen, an alkyl group, an alkoxy group, halogen, a carboxyl group or a sulfonic acid group; R.sup.3 and R.sup.4 each represent a hydroxyl group, halogen, an alkoxy group, an unsubstituted or substituted amino group; X represents --O--, --CH.sub.2 --, --C.sub.2 H.sub.4 --, --CH.dbd.CH--, --S--, --SO.sub.2 -- or --; Ar.sup.1 and Ar.sup.2 each represent an unsubstituted or substituted phenyl group, an unsubstituted or substituted naphthyl group; M represents hydrogen ion, an alkali metal cation, amine cation or an ammonium ion; and n is an integer of 1, 2 or 3.
    Type: Grant
    Filed: October 22, 1985
    Date of Patent: April 12, 1988
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaru Shimada, Toshiyuki Kawanishi, Kakuji Murakami, Tamotsu Aruga, Hiroyuki Uemura
  • Patent number: 4713113
    Abstract: An aqueous ink composition for ink-jet recording comprising an aqueous solution of a water-soluble dye of formula (I) and a humectant dissolved in water: ##STR1## wherein R.sup.1 and R.sup.2 each represent hydrogen, an alkyl group, an alkoxy group, halogen, a carboxyl group or a sulfonic acid group; A represents ##STR2## wherein R.sup.3 represents an alkyl group, a phenyl group, a carbamoyl group or a carboxyl group; R.sup.4 represents an unsubstituted or substituted phenyl group, an unsubstituted or substituted napthyl group, or an unsubstituted or substituted alkyl group; R.sup.5 represents a hydroxyl group or an amino group; R.sup.6 represents a hydroxyl group or an unsubstituted or substituted amino group; M represents hydrogen, an alkali metal cation, amine cation or an ammonium ion; m is an integer of 0 or 1; and n is an integer of 1, 2 or 3.
    Type: Grant
    Filed: October 22, 1985
    Date of Patent: December 15, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaru Shimada, Toshiyuki Kawanishi, Kakuji Murakami, Tamotsu Aruga, Hiroyuki Uemura
  • Patent number: 4711668
    Abstract: An aqueous ink composition comprising a water-soluble dye having the formula (I) in an amount sufficient for ink printing and water, ##STR1## wherein R.sup.1 and R.sup.2 each represent hydrogen, a lower alkyl group, a lower alkoxy group or halogen; R.sup.3 represents hydrogen, a lower alkyl group, a lower alkoxy group, halogen, a sulfonic acid group or a sulfonate group; Z.sup.1 and Z.sup.2 each represent hydrogen, a lower alkyl group, a phenyl group, an acetyl group, an alkyl sulfonyl group, a benzoyl group which may have a substituent, a benzenesulfonyl group which may have a substituent, or a 1,3,5-triazine group which may have a substituent; M represents hydrogen, an alkali metal or NH.sub.4.sup.+ ; and n is an integer of 1 or 2.
    Type: Grant
    Filed: April 14, 1986
    Date of Patent: December 8, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaru Shimada, Toshiyuki Kawanishi, Kakuji Murakami, Tamotsu Aruga, Hiroyuki Uemura, Kiyofumi Nagai
  • Patent number: 4680235
    Abstract: A recording material for ink jet printing for forming images thereon with an ink composition by ink jet printing is disclosed, which comprises a base material and a surface recording layer formed thereon, the surface recording layer contains at least a surface active agent which does not form a material insoluble in the ink composition in combination with a dye contained in the ink composition.
    Type: Grant
    Filed: March 22, 1985
    Date of Patent: July 14, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Kakuji Murakami, Eiichi Akutsu, Tamotsu Aruga
  • Patent number: 4647310
    Abstract: An aqueous ink composition for ink-jet recording comprising an aqueous solution of a water-soluble dye of formula (I) and a humectant dissolved in water: ##STR1## wherein Ar represents an unsubstituted or substituted phenyl group, or an unsubstituted or substituted naphthyl group; X represents a hydroxyl group, an alkoxy group, a halogen atom, an alkylamino group, a hydroxyalkylamino group, a cyclic amino group or an anilino group; M represents hydrogen, K, Na, Li, NH.sub.4 or an organic amine cation; and n is an integer of 1 or 2.
    Type: Grant
    Filed: February 24, 1986
    Date of Patent: March 3, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaru Shimada, Toshiyuki Kawanishi, Kakuji Murakami, Tamotsu Aruga, Hiroyuki Uemura, Kiyofumi Nagai
  • Patent number: 4631085
    Abstract: An aqueous ink composition for ink-jet recording comprising an aqueous solution of a water-soluble dye of formula (I) and a humectant dissolved in water: ##STR1## wherein R.sup.1 represents ##STR2## wherein R.sup.4 represents an alkyl group or a hydroxyalkyl group; R.sup.2 represents hydrogen, an alkyl group, an acetyl group, an unsubstituted or substituted benzoyl group, an unsubstituted or substituted benzenesulfonyl group, or a substituted 1,3,5-triazine ring; R.sup.3 represents hydrogen, an alkyl group, an alkoxy group, halogen or a sulfonic acid group; M represents hydrogen ion, an alkali metal cation, amine cation or an ammonium ion; and n is an integer of 1, 2 or 3.
    Type: Grant
    Filed: October 22, 1985
    Date of Patent: December 23, 1986
    Assignee: Ricoh Company, LTD.
    Inventors: Toshiyuki Kawanishi, Masaru Shimada, Kakuji Murakami, Tamotsu Aruga, Hiroyuki Uemura
  • Patent number: RE33155
    Abstract: An aqueous ink is disclosed, which comprises a first magenta dye having the formula (I), a second magenta dye having the formula (II), a water-soluble organic solvent having a boiling point of 100.degree. C. or higher, water and a preservative and anti-mold agent: ##STR1## wherein K.and R.sup.2 each represent ##STR2## (in which R.sup.5, R.sup.6, R.sup.7 and R.sup.8 each represent a lower alkyl group, an amino group, a sulfonic acid group in the form of an alkali metal salt, or a carboxyl group in the form of an alkali metal salt); R.sup.3 and R.sup.4 each represent a lower alkyl group, an amino group, a sulfonic acid group in the form of an alkali metal salt, or a carboxyl group in the form of an alkali metal salt; and k, l, m and n each represent an integer of 0, 1 or 2.
    Type: Grant
    Filed: April 5, 1988
    Date of Patent: January 30, 1990
    Assignee: Ricoh Company, Limited
    Inventors: Eiichi Akutsu, Kakuji Murakami, Tamotsu Aruga