Patents by Inventor Tomiko Kawakami

Tomiko Kawakami 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: 4508570
    Abstract: An aqueous ink for ink-jet printing comprises as its main components (i) a water-soluble direct dye and/or acid dye, (ii) a polyhydric alcohol and/or an alkyl ether thereof, (iii) water, and (iv) at least one water-soluble non-ionic surface active agent selected from the group consisting of a polyoxyethylene alkyl amine of formula (I), a polyoxyethylene alkyl phenyl ether of formula (II) and a polyoxyethylene alkyl ether of formula (III): ##STR1## where R.sup.1 represents a group derived from a chain hydrocarbon with 16 to 19 carbon atoms; m, an integer of 0 through 18; and n, an integer of 0 through 18; where m+n equals 8 through 18; ##STR2## where R.sup.2 represents a group derived from a chain hydrocarbon with 7 to 12 carbon atoms; and x represents an integer of 12 through 20; ##STR3## where R.sup.3 and R.sup.4 each represent a group derived from a chain hydrocarbon with 6 to 8 carbon atoms; and y represents an integer of 10 through 15.
    Type: Grant
    Filed: October 18, 1982
    Date of Patent: April 2, 1985
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadashi Fujii, Tomoyuki Yamaguchi, Kakuji Murakami, Tomiko Kawakami, Hiroko Uenozono
  • Patent number: 4338388
    Abstract: An electrophotographic element is prepared by forming a photoconductive layer containing a hydrazone compound therein on an electroconductive support member. The hydrazone compounds represented by the following general formula, are useful as photoconductive materials and as charge transport materials for use in electrophotography: ##STR1## wherein Ar represents a substituted or unsubstituted condensed polycyclic group or heterocyclic group, and R represents a methyl group, an ethyl group, a benzyl group or a phenyl group. The condensed polycyclic group includes a naphthalene ring, and an anthracene ring. The heterocyclic ring includes nitrogen, oxygen and sulfur.
    Type: Grant
    Filed: October 10, 1979
    Date of Patent: July 6, 1982
    Assignee: Ricoh Company, Limited
    Inventors: Kiyoshi Sakai, Mitsuru Hashimoto, Tomiko Kawakami
  • Patent number: 4325871
    Abstract: A bis-azo compound of the formula ##STR1## wherein A represents ##STR2## wherein R represents alkyl, alkoxy, nitro, dialkylamino or halogen, and n represents an integer 0, 1, 2 or 3 and when n is 2 or 3, R represents identical or different substituents selected from the group of alkyl, alkoxy, nitro, dialkylamino and halogen. The bis-azo compound is useful as a photoconductive material for the preparation of electrophotographic photoconductors.
    Type: Grant
    Filed: June 11, 1980
    Date of Patent: April 20, 1982
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaomi Sasaki, Mitsuru Hashimoto, Tomiko Kawakami
  • Patent number: 4297426
    Abstract: An electrophotographic element comprising a conductive substrate and a mono-layer type or multi-layer type photosensitive layer, superposed thereon, containing a photoconductive material in which said photoconductive material is a hydrazone compound having the following general formula (I) or an anile compound having the following general formula (II): ##STR1## [where R.sub.1 is a methyl, ethyl 2-hydroxyethyl or 2-chloroethyl group; R.sub.2 is a methyl, ethyl, benzyl or phenyl group; and R.sub.3 is chlorine, bromine, a C.sub.1 -C.sub.4 alkyl group, a C.sub.1 -C.sub.4 alkoxy group, a dialkylamino group with C.sub.1 -C.sub.4 alkyl or a nitro group.] ##STR2## [where R.sub.1 is the same as the said general formula (I); and R.sub.4 is a substituted or non-substituted phenyl, naphthyl, heterocyclic or C.sub.1 -C.sub.10 alkyl group.
    Type: Grant
    Filed: May 21, 1980
    Date of Patent: October 27, 1981
    Assignee: Ricoh Co., Ltd.
    Inventors: Kiyoshi Sakai, Mitsuru Hashimoto, Tomiko Kawakami
  • Patent number: 4268596
    Abstract: The present invention provides an electrophotographic element which comprises an electroconductive support and a photosensitive layer, formed thereon, which contains some disazo pigment expressed by the general formula ##STR1## [wherein A represents ##STR2## (wherein X represents aromatic ring, hetero ring or substitutes thereof, R.sub.1 represents aromatic ring, hetero ring or substitutes thereof, Ar.sub.2 and Ar.sub.3 represents aromatic ring or substitutes thereof, R.sub.1 and R.sub.3 represents hydrogen, lower alkyl group, phenyl group or substitutes thereof, and R.sub.2 represents lower alkyl group, carboxyl group or esters thereof)].
    Type: Grant
    Filed: November 21, 1979
    Date of Patent: May 19, 1981
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaomi Sasaki, Mitsuru Hashimoto, Tomiko Kawakami
  • Patent number: 4247614
    Abstract: The present invention provides an electrophotographic element which comprises some disazo pigment expressed by the general formula ##STR1## [wherein R.sub.1 represents a member selected from the group consisting of hydrogen atom, methyl radical, ethyl radical, methoxy radical, ethoxy radical, chlorine atom, bromine atom, nitro radical, dimethylamino radical, diethylamino radical and phenyl radical; A represents ##STR2## (wherein R.sub.2 represents hydrogen atom or chlorine atom) or ##STR3## and n is an interger of 1 or 2.] as effective component contained in the photosensitive layer thereof.
    Type: Grant
    Filed: November 16, 1979
    Date of Patent: January 27, 1981
    Assignee: Ricoh Co., Ltd.
    Inventors: Masafumi Ohta, Kiyoshi Sakai, Mitsuru Hashimoto, Masaomi Sasaki, Tomiko Kawakami