Patents by Inventor Visvanathan Ramanathan

Visvanathan Ramanathan 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: 5196521
    Abstract: The dyes of the formula ##STR1## in which R.sub.1 is hydrogen, halogen or CF.sub.3 and R.sub.2 is substituted or unsubstituted alkyl, where R.sub.2 must not be ethoxycarbonylethyl if R.sub.1 is hydrogen are suitable for the dyeing of polyester material in red hues having very good lightfastness.
    Type: Grant
    Filed: June 24, 1991
    Date of Patent: March 23, 1993
    Assignee: Ciba-Geigy Corporation
    Inventors: Visvanathan Ramanathan, Angelo D. Casa
  • Patent number: 4927865
    Abstract: Anthraquinones of formula I ##STR1## wherein X is the group --CR.sup.2 R.sup.3 --, where R.sup.2 is H, --CH or C.sub.1 -C.sub.5 -alkyl and R.sup.3 is H or --CN, R.sup.1 is H or C.sub.1 -C.sub.5 -alkyl and R is a direct bond or linear or branched C.sub.1 -C.sub.18 -alkylene which, alone or together with the --CR.sup.2 R.sup.3 -- group, can be interrupted by one or more --O-- when R.sup.2 and/or R.sup.3 are not --CN, and curable compositions comprising (a) an epoxy resin, (b) a hardener if necessary, (c) an anthraquinone of formula I and (d) an amino alcohol. The cured compositions are photosensitive and are suitable for the preparation of coatings and metallic images by electroless metal deposition.
    Type: Grant
    Filed: May 12, 1989
    Date of Patent: May 22, 1990
    Assignee: Ciba-Geigy Corporation
    Inventors: Rudolf Duthaler, Jurgen Finter, Walter Fischer, Visvanathan Ramanathan
  • Patent number: 4924015
    Abstract: Anthraquinones having .alpha.,.alpha.-(dialkyl)alkyl groups which are functionally substituted, for example by --COOH or --CONH--NH.sub.2, are described. Compositions which contain such anthraquinones, an aminoalcohol and an epoxy resin with or without a hardener are suitable for preparing metallic coatings and images on the cured composition by exposure to light and currentless metal deposition.
    Type: Grant
    Filed: June 20, 1988
    Date of Patent: May 8, 1990
    Assignee: Ciba-Geigy Corporation
    Inventors: Frederick H. Howell, Rudolf Duthaler, Jurgen Finter, Konrad Oertle, Visvanathan Ramanathan
  • Patent number: 4855084
    Abstract: Anthraquinones of formula I ##STR1## wherein X is the group --CR.sup.2 R.sup.3 --, where R.sup.2 is H, --CN or C.sub.1 -C.sub.5 -alkyl and R.sup.3 is H or --CN, R.sup.1 is H or C.sub.1 -C.sub.5 -alkyl and R is a direct bond or linear or branched C.sub.1 -C.sub.18 -alkylene which, alone or together with the --CR.sup.2 R.sup.3 -- group, can be interrupted by one or more --O-- when R.sup.2 and/or R.sup.3 are not --CN, and curable compositions comprising (a) an epoxy resin, (b) a hardener if necessary, (c) an anthraquinone of formula I and (d) an amino alcohol. The cured compositions are photosensitive and are suitable for the preparation of coatings and metallic images by electroless metal deposition.
    Type: Grant
    Filed: June 20, 1988
    Date of Patent: August 8, 1989
    Assignee: Ciba-Geigy Corporation
    Inventors: Rudolf Duthaler, Jurgen Finter, Walter Fischer, Visvanathan Ramanathan
  • Patent number: 4654384
    Abstract: Novel water-soluble triazine compounds of the formula ##STR1## in which D and D.sub.1 independently of one another are radicals of diazo components, R and R.sub.1 independently of one another are hydrogen or C.sub.1 -C.sub.4 -aklyl, X is a monosubstituted or disubstituted amino group, a C.sub.1 -C.sub.4 -alkoxy group or an aryloxy group, the symbols Y are basic or cationic groups, which can be identical or different, l is 2, 3, 4, 5 or 6 and n is 0 or 1, and the number of basic and/or cationic groups Y in the molecule must be equal to or greater than the number of SO.sub.3 H groups are useful as dyes for dyeing and printing textile materials, leather and in particular, paper. The dyeings have good general fastness properties and the effluents remain colorless.
    Type: Grant
    Filed: January 12, 1984
    Date of Patent: March 31, 1987
    Assignee: Ciba-Geigy Corporation
    Inventors: Visvanathan Ramanathan, Peter Mockli
  • Patent number: 4581445
    Abstract: There are described novel cationic benzothiazole disazo compounds of the formula ##STR1## K independently of one another are each a coupling component, R independently of one another are each an unsubstituted or substituted C.sub.1 -C.sub.4 -alkyl group,R.sub.1 independently of one another are each hydrogen, unsubstituted or substituted C.sub.1 -C.sub.4 -alkyl, unsubstituted or substituted C.sub.1 -C.sub.4 -alkoxy, or halogen,X is the direct bond, --(CH.sub.2).sub.y wherein y is a number from 1 to 4, --CH.dbd.CH--, a phenylene group, a naphthylene group, a heterocyclic radical, an --NH-alkylene-(C.sub.1 -C.sub.6)--NH-- radical or an --NH-arylene-NH-- radical, andAn is an anion, with the proviso that when the coupling component K is a dimethylaminophenyl radical, the divalent bridge member X is not the --(CH.sub.2).sub.2 -- group are useful for dyeing and printing textile materials, leather and in particular paper. The dyeings obtained have good fastness properties, especially good fastness on paper to light.
    Type: Grant
    Filed: September 16, 1983
    Date of Patent: April 8, 1986
    Assignee: Ciba-Geigy Corporation
    Inventor: Visvanathan Ramanathan
  • Patent number: 4562247
    Abstract: There are described azo compounds of the formula ##STR1## wherein D.sub.1 and D.sub.2 are each the radical of a diazo component, R is C.sub.1 -C.sub.4 -alkyl or C.sub.1 -C.sub.4 alkyl substituted by C.sub.1 -C.sub.4 -alkoxy or halogen or is phenyl or phenyl substituted by C.sub.1 -C.sub.4 -alkyl, halogen or C.sub.1 -C.sub.4 alkoxy, and Y is a basic or cationic group. These azo compounds can be used as dyes for dyeing and printing natural and synthetic, cationically dyeing substrates, particularly textile materials and paper.
    Type: Grant
    Filed: May 29, 1984
    Date of Patent: December 31, 1985
    Assignee: Ciba Geigy Corporation
    Inventor: Visvanathan Ramanathan
  • Patent number: 4517358
    Abstract: Cationic disazo compounds of the formula ##STR1## wherein K independently of one another are each a coupling component,R independently of one another are each an unsubstituted or substituted C.sub.1 -C.sub.4 -alkyl group,R.sub.1 independently of one another are each hydrogen, unsubstituted or substituted C.sub.1 -C.sub.4 -alkyl, unsubstituted or substituted C.sub.1 -C.sub.4 -alkoxy, or halogen, andAn is an anionare useful as dyes, in particular as paper dyes, whereby dyeings fast to water are obtained. The dyeings obtained have very good fastness to light and to wet processing.Disazo compounds of the formula ##STR2## wherein K and R, are as defined above are useful as disperse dyes and as intermediates in the preparation of the above cationic disazo compounds.
    Type: Grant
    Filed: September 14, 1982
    Date of Patent: May 14, 1985
    Assignee: Ciba-Geigy Corporation
    Inventor: Visvanathan Ramanathan
  • Patent number: 4208324
    Abstract: Azo dyes which are free from acid water-solubilizing groups and correspond to the formula ##STR1## wherein two radicals Z represent groups of the formula --NR'R" and one of the radicals Z represent a group of the formulae --NR'R", OR'" or --S--R'", wherein R', R" and R'"each represents hydrogen, aryl, alkyl, aralkyl, cycloalkyl, an aliphatic or a heterocyclic radical and R' and R" are able to form a ring which contains the amino nitrogen, and the radicals --NR'R" may be the same or different, R is alkyl, substituted alkyl, cycloalkyl or substituted cycloalkyl, n is 1 or 2, Y represents a radical of the formulae --CN or --CONH.sub.2, and D is the radical of an aromatic or heterocyclic diazo component; the nucleus A containing three double bonds if n is 1 and two double bonds if n is 2. The new dyestuffs dye polyester fibres in yellow and red shades.
    Type: Grant
    Filed: July 7, 1978
    Date of Patent: June 17, 1980
    Assignee: Ciba-Geigy Corporation
    Inventor: Visvanathan Ramanathan
  • Patent number: 4179435
    Abstract: Dyestuffs of the formula ##STR1## wherein D is a heterocyclic diazo component,R.sub.1 is an alkyl radical which may be substituted,R.sub.2 is phenylene or alkylened is hydrogen, chloro, lower alkyl, lower alkoxy, aryl, aryloxy or arylmercapto, andR is an optionally substituted alkyl, aryl or amino group, dye polyester fibers in red and blue shades with good fasteners, and are suitable for use in the thermosol process.
    Type: Grant
    Filed: June 22, 1978
    Date of Patent: December 18, 1979
    Assignee: Ciba-Geigy Corporation
    Inventor: Visvanathan Ramanathan
  • Patent number: 4116965
    Abstract: A styryl dye devoid of acid, water-solubilizing groups, of the formula ##STR1## wherein two radicals Z represent groups of the formula --NR'R" and one Z represents a group of the formulae --NR'R", --OR'" or --S--R'", in which each of R', R" and R'" represents hydrogen unsubstituted phenyl, substituted phenyl, benzyl, phenylethyl, cyclohexyl, or an aliphatic radical containing up to 8 carbon atoms and R' and R'" are able to form a ring containing the amino nitrogen and the radicals --NR'R" may be the same or different, Y represents a radical of the formula --CN or --CONH.sub.2, and W represents the radical of an organic compound, which contains an active methylene group and which is bonded to the --CH.dbd. group through the carbon atom of the active methylene group, and Z.sub.3 is furthermore an unsubstituted or a substituted hydrocarbon radical containing up to 8 carbon atoms.
    Type: Grant
    Filed: November 18, 1976
    Date of Patent: September 26, 1978
    Assignee: Ciba-Geigy Corporation
    Inventors: Nalin Binduprasad Desai, Visvanathan Ramanathan
  • Patent number: 4115381
    Abstract: Dyestuffs of the formula ##STR1## wherein D is a diazo component of the benzene series,R.sub.1 is an alkyl radical,R.sub.2 is alkylene andR is alkyl, aryl or di-substituted amino, dye polyester fibers in red and blue shades with good fastness. The dyestuffs can be used in the thermosol process.
    Type: Grant
    Filed: September 14, 1976
    Date of Patent: September 19, 1978
    Assignee: Ciba-Geigy Corporation
    Inventor: Visvanathan Ramanathan
  • Patent number: 4101541
    Abstract: Azo dyestuffs, free from sulfo groups, containing a 3-cyano-1,2,4-thiadiazole diazo component are disclosed. These dyestuffs are useful in dyeing and printing synthetic fibers, for example, especially polyester fibers and polypropylene fibers which have been metal modified.
    Type: Grant
    Filed: October 4, 1976
    Date of Patent: July 18, 1978
    Assignee: Ciba-Geigy Corporation
    Inventors: Jean Claude Petitpierre, Visvanathan Ramanathan
  • Patent number: 4091025
    Abstract: A process for the manufacture of 2,4,6-triamino-5-nitro-pyridines of the general formula ##STR1## wherein each of R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 represents a hydrogen atom, a substituted or unsubstituted aryl, aralkyl or cycloalkyl group or an aliphatic group, and R.sub.1 and R.sub.2, R.sub.3 and R.sub.4, and R.sub.5 and R.sub.6 together can form a ring which contains the amino-nitrogen, which process comprises(a) aminating a 2-halogeno-3-cyano-4,6-diaminopyridine, preferably 2-bromo-3-cyano-4,6-diamino-pyridine either to give the triaminopyridine of the formula ##STR2## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.
    Type: Grant
    Filed: October 7, 1976
    Date of Patent: May 23, 1978
    Assignee: Ciba-Geigy AG
    Inventors: Ulrich Schlesinger, Visvanathan Ramanathan
  • Patent number: 4084053
    Abstract: Polycyclic compounds of the general formula I ##STR1## in which the nucleus A can be further substituted, Y is a hydrogen atom or an optionally substituted hydrocarbon radical, and R.sub.1 and R.sub.2 each denote hydrogen, aryl, aralkyl, cycloalkyl or an aliphatic radical, and R.sub.1 and R.sub.2 can form a ring containing the amine nitrogen and mixtures thereof with one another. The dyestuffs dye natural and synthetic fibres in fast yellow and orange shades.
    Type: Grant
    Filed: June 16, 1975
    Date of Patent: April 11, 1978
    Assignee: Ciba-Geigy Corporation
    Inventors: Nalin Binduprasad Desai, Visvanathan Ramanathan
  • Patent number: 4083688
    Abstract: Polyester fibers dyed with a disazo dyestuff consisting of two N-phenyl-pyrazole monoazo dyestuff moieties bound to each other via the phenyl groups, said phenyl groups attached to each other by an --O--, --S--, --NH--, cyclohexylidene, C.sub.1 -C.sub.2 -alkylene or --O-(C.sub.1 -C.sub.2 -alkylene)-O- divalent radical.
    Type: Grant
    Filed: October 29, 1973
    Date of Patent: April 11, 1978
    Assignee: Ciba-Geigy AG
    Inventor: Visvanathan Ramanathan
  • Patent number: 4068085
    Abstract: An azo dyestuff of the formula ##STR1## wherein two of the radicals Z denote groups of the formula --NR'R" and one radical Z denotes a group of the formulae --NR'R", --OR' or --S-R', and R' and R" and R" each denote hydrogen, aryl, aralkyl, cycloalkyl or an aliphatic radical and R' and R" can form a ring containing the amine nitrogen and the radicals --NR'R" can be identical to, or different from, one another, Z.sub.3 is also a hydrogen, chlorine or bromine atom or an optionally substituted hydrocarbon radical and D is the radical of an aromatic or heterocyclic diazo component. The new dyestuffs dye synthetic fibers, such as polyester and acrylic fibers in fast yellow, and red shades.
    Type: Grant
    Filed: December 1, 1975
    Date of Patent: January 10, 1978
    Assignee: Ciba-Geigy Corporation
    Inventors: Visvanathan Ramanathan, Ulrich Schlesinger, Rene De Montmollin
  • Patent number: 4033943
    Abstract: Water-soluble azo dyes of the formula WHEREIN Y is a fiber-reactive group, n is 1 or 2, m is 0, 1 or 2 and the benzene rings A and B may be further substituted are disclosed. They are useful for dyeing nitrogen-containing fibers and cellulose materials and are distinguished by very bright and brilliant shades, possessing good stability, fastness to light, wet processing and fixation.
    Type: Grant
    Filed: February 21, 1975
    Date of Patent: July 5, 1977
    Assignee: Ciba-Geigy Corporation
    Inventors: Visvanathan Ramanathan, Angelo Della Casa, Rene DE Montmollin, Gert Hegar, Hans Ulrich Schutz
  • Patent number: 4033716
    Abstract: A process for dyeing and printing hydrophilic fibrous material by the transfer printing process using carriers that are treated with at least one transferable, metallizable dye or color former and optionally a binder that is stable below 230.degree. C, which comprises impregnating the material to be dyed or printed with a solution which containsA. at least one organic solvent with a boiling point higher than 100.degree. C andB. at least one compound that yields complex forming metals, drying the impregnated material and bringing it into contact with the treated carrier, then subjecting both material and carrier to a heat treatment, and subsequently providing the resultant print with an aftertreatment.
    Type: Grant
    Filed: October 15, 1974
    Date of Patent: July 5, 1977
    Assignee: Ciba-Geigy AG
    Inventors: Raymond Defago, Visvanathan Ramanathan, Gerhard Back
  • Patent number: 3971740
    Abstract: Azo dyestuffs containing at least one group of formula --X--CO--NR--SO.sub.2 aryl, wherein R is hydrogen alkyl or cycloalkyl and X is an oxygen or sulphur atom or a group of formula --NR.sub.1 --, wherein R.sub.1 is hydrogen alkyl or cycloalkyl. The dyestuffs dye polyester fibers in fast shades.
    Type: Grant
    Filed: March 5, 1974
    Date of Patent: July 27, 1976
    Assignee: Ciba-Geigy AG
    Inventors: Nalin Binduprasad Desai, Ponnusami Jayaraman, Visvanathan Ramanathan, Klaus Artz, Navnitrai Nagarji Naik, Walter Jenny