Patents Represented by Attorney, Agent or Law Firm Robert T. Barker
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Patent number: 6465437Abstract: This invention relates to a novel crystalline diphosphate salt of (2R,3S,4R,5R,8R,10R,11R,12S,13S,14R)-13-[[2,6-dideoxy-3-C-methyl-3-O-methyl-4-C-[(propylamino)methyl]-&agr;-L-ribo-hexopryanosyl]oxy]-2-ethyl-3,4,10-trihydroxy-3,5,8,10,12,14-hexamethyl-11-[[3,4,6-trideoxy-3-(dimethylamino)-&bgr;-D-xylo-hexopyranosyl]oxy]-1-oxa-6-azacyclopentadecan-15-one that is useful as an antibacterial and antiprotozoal agent in mammals. This invention also relates to pharmaceutical compositions containing the free base of the diphosphate salt and the methods of treating bacterial and protozoal infections in mammals by administering the free base of the diphosphate to mammals requiring such treatment. The free base of the diphosphate salt of the present invention possesses potent activity against various bacterial and protozoal infections when given by parenteral application to mammals.Type: GrantFiled: May 18, 2000Date of Patent: October 15, 2002Assignee: Pfizer Inc.Inventors: Robert J. Rafka, Colman B. Ragan, Douglas J. M. Allen
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Patent number: 6380200Abstract: This invention is directed to methods, pharmaceutical compositions and kits comprising an aldose reductase inhibitor (ARI), a prodrug thereof or a pharmaceutically acceptable salt of said ARI or said prodrug and selective serotonin reuptake inhibitor (SSRI), a prodrug thereof or a pharmaceutically acceptable salt of said SSRI or said prodrug. This invention further relates to methods of using those pharmaceutical compositions for the treatment of diabetic complications such as diabetic neuropathy, diabetic nephropathy, diabetic retinopathy, myocardial infarction, cataracts and diabetic cardiomyopathy.Type: GrantFiled: December 1, 2000Date of Patent: April 30, 2002Assignee: Pfizer, Inc.Inventor: Banavara L. Mylari
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Patent number: 6248858Abstract: Polymerization of polycarbonates is performed by first enhancing the crystallinity of a precursor polycarbonate, such as an oligomer, by contact in pellet form with an alkanol in the liquid or vapor state as non-solvent, and then conducting solid state polymerization in a stream of inert gas such as nitrogen. The solid state polymerization operation includes a stage of heating at a constant temperature in the range of about 215-225° C., optionally combined with a first heating stage at a constant temperature in the range of about 180-190° C. The method is adaptable to continuous operation and produces a polycarbonate having a number average molecular weight, as determined by gel permeation chromatography relative to polystyrene, of at least 15,000.Type: GrantFiled: November 16, 1998Date of Patent: June 19, 2001Assignee: General Electric CompanyInventors: James Day, Godavarthi Satyana Varadarajan
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Patent number: 6214892Abstract: This invention relates to a method of recovering a polymer from an organic mixture comprising polymer and an organic solvent, the method comprising: a) admixing an aqueous solution and the organic mixture by the application of a combined mechanical and hydraulic shear force, the combined mechanical and shear force being sufficient to form a liquid-liquid dispersion; b) removing the organic solvent from the liquid-liquid dispersion thereby forming a remaining solution; and c) separating the polymer from the remaining solution. In one embodiment the polymer is a polycarbonate prepared by the interfacial method, and the organic solvent is methylene chloride.Type: GrantFiled: December 23, 1999Date of Patent: April 10, 2001Assignee: General Electric CompanyInventors: Qiwei He, Paul Russell Wilson, Paul William Buckley, Allen Wai Yee Ko, Larry Allen Divins
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Patent number: 6143858Abstract: This invention relates to polyestercarbonates comprising residues of at least one branched aliphatic dicarboxylic acid, and methods for preparation of polyestercarbonates comprising residues of at least one branched aliphatic dicarboxylic acid. This invention further relates to articles and methods of making articles from the polyestercarbonates.Type: GrantFiled: July 30, 1999Date of Patent: November 7, 2000Assignee: General Electric CompanyInventors: David Paul Mobley, Mohan Amaratunga, Gary Charles Davis, Peter David Phelps
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Patent number: 6140461Abstract: Amorphous precursor polycarbonates, such as oligomers, are converted to high molecular weight polycarbonates in a unitary series of operations that includes contact with an alkanol having a boiling point up to about 180.degree. C. and heating the resulting wetted particles so as to effect solid state polymerization. Heating is at progressively increasing temperatures from below the boiling point of the alkanol to a final level between the Tg and the melting temperature of said enhanced crystallinity polycarbonate.Type: GrantFiled: August 10, 1999Date of Patent: October 31, 2000Assignee: General Electric CompanyInventors: James Day, Bhaskar Bhairavnath Idage
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Patent number: 6117968Abstract: The level of anhydride linkages in copolyestercarbonates is decreased by preparing the copolyestercarbonate interfacially in a two-step method from at least one dihydroxyaromatic compound and at least one dicarboxylic acid. The first step is conducted at a pH in the range of about 4.5-9.5, employing the combination of a phase transfer catalyst such as a tetraalkylammonium halide and a tertiary amine such as triethylamine. The proportion of the phase transfer catalyst is in the range of about 3-12 mole percent based on total dihydroxyaromatic compound and dicarboxylic acid employed. In the second phosgenation step, the pH is raised to at least 10 and a stoichiometric phosgene excess of at least 5% is introduced.Type: GrantFiled: December 23, 1997Date of Patent: September 12, 2000Assignee: General Electric CompanyInventors: Gary Charles Davis, Niles Richard Rosenquist, Paul Dean Sybert
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Patent number: 6103855Abstract: A method of preparing a polycarbonate comprising the steps of:a) charging at least one dihydroxy compound, an inert solvent, water, caustic, carbonyl halide, and catalyst to a vessel, and maintaining the pH of the reaction mixture between about 4 and about 12 during charging; andb) within an interval of between 0 and about 90% of the total carbonyl halide addition to the vessel, activating a reaction system that produces monofunctional aromatic chloroformates (MAC) and introducing the MAC to the vessel within the interval of 0 to about 90% of the total carbonyl halide addition to the vessel; where the MAC reaction system is coupled with the vessel, and where means are provided for delivery of the MAC from the reaction system to the vessel.Type: GrantFiled: March 30, 1999Date of Patent: August 15, 2000Assignee: General Electric CompanyInventors: James Manio Silva, David Michel Dardaris, Larry Ivis Flowers, James Franklin Hoover, Allen Wai-Yee Ko
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Patent number: 6060577Abstract: This invention relates to polycarbonates containing residues derived from alicyclic bisphenols or derivatives of alicyclic bisphenols; and optical articles formed from these polycarbonates. The polycarbonates have suitable properties for use in optical data storage media.Type: GrantFiled: March 18, 1999Date of Patent: May 9, 2000Assignee: General Electric CompanyInventor: Gary Charles Davis
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Patent number: 6060576Abstract: Copolycarbonates of enhanced crystallinity, suitable for solid state polymerization, are prepared by melt blending, under non-reactive conditions, an amorphous precursor polycarbonate such as a bisphenol A polycarbonate with one or more other monomers which may include a spiro(bis)indane bisphenol and/or a phenylindane bisphenol, optionally with a polyoxyalkylene glycol. The resulting blend is pelletized and the crystallinity of the resulting pellets is enhanced, typically by contact with an alkanol liquid or vapor.Type: GrantFiled: January 28, 1999Date of Patent: May 9, 2000Assignee: General Electric CompanyInventors: Marc Brian Wisnudel, James Day, Gautam Chatterjee
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Patent number: 6034142Abstract: Polycarbonates are recycled without the need for chemical modification by dissolution in a solvent followed by removal of any insoluble materials and precipitation by addition of a non-solvent. The precipitation step may be followed by solid state polymerization of the recycled polycarbonate. Particularly when solid state polymerization is to be performed, the use of a combination of solvent and non-solvent which produces a crystalline intermediate is performed, and use of a modifying reagent increasing the hydroxy end group concentration of the polycarbonate may be advantageous.Type: GrantFiled: December 12, 1997Date of Patent: March 7, 2000Assignee: General Electric CompanyInventors: Godavarthi Satyanarayana Varadarajan, Joseph Anthony King, Jr., Bhaskar Bhairavnath Idage, Swaminathan Sivaram, Vishnu Ramchandra Ranade
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Patent number: 6031063Abstract: The crystallinity of an amorphous precursor polycarbonate is enhanced by contact in the liquid or vapor state with a non-solvent which may be water, an alkanol or a mixture thereof and which is dialkyl carbonate-free. Contact temperatures are at least about 75.degree. C. and are further defined by the relationshipT.sub.c .gtoreq.T.sub.b -z,wherein T.sub.c is the contact temperature, T.sub.b is the boiling point of the non-solvent at the contact pressure employed (both in degrees C.) and z is a constant whose value is 60.Type: GrantFiled: August 9, 1999Date of Patent: February 29, 2000Assignee: General Electric CompanyInventors: James Day, Bhaskar Bhairavnath Idage, Andrew James Caruso
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Patent number: 6031062Abstract: Crystallinity of amorphous precursor polycarbonates is enhanced by contact with at least on diaryl carbonate such as diphenyl carbonate, followed by pelletization and heating to a temperature above the melting point of the diaryl carbonate and below the glass transition temperature of the amorphous precursor polycarbonate. The crystallinity enhancement operation may be conducted in the presence of dihydroxyorganic monomers and may be followed by a solid state polymerization operation.Type: GrantFiled: January 28, 1999Date of Patent: February 29, 2000Assignee: General Electric CompanyInventors: James Day, Gautam Chatterjee
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Patent number: 6001953Abstract: The invention relates to polycarbonates suitable for use in optical articles; the polycarbonates contain residues of alicyclic bisphenols and have properties particularly suited for use in high density optical data storage media. The polycarbonates further contain residues of other monomers, such as SBI and its derivatives; bisphenols, such as bisphenol A; CD-1 and its derivatives or some combination of each.Type: GrantFiled: March 18, 1999Date of Patent: December 14, 1999Assignee: General Electric CompanyInventors: Gary Charles Davis, Andrew James Caruso, Joseph Richard Wetzel, Ramesh Hariharan, Marc Brian Wisnudel
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Patent number: 5969086Abstract: Quaternary salts having a double helix structure are prepared by the reaction of dihydroxyaromatic compound, preferably a bisphenol, with an alkali metal hydroxide and a quaternary salt, such as a tetraalkylammonium or hexaalkylguanidinium chloride. The quaternary salts and their alkaline hydrolysis products are useful as catalysts in various reactions, including imide formation from bisphenol salts and halo- or nitro-substituted phthalimides and redistribution and equilibration of polycarbonates.Type: GrantFiled: December 15, 1997Date of Patent: October 19, 1999Assignee: General Electric CompanyInventors: Jimmy Lynn Webb, Thomas Link Guggenheim, Robert Joseph Nick, Patrick Joseph McCloskey, Joseph Anthony King, Jr.
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Patent number: 5948876Abstract: Branched polycarbonates are prepared by the reaction of a linear or branched polycarbonate with a branching resin having a molecular weight up to about 3,000, typically a novolak or a bisphenol polymer. The reaction preferably takes place in the presence of a carbonate equilibration catalyst such as a quaternary bisphenolate.Type: GrantFiled: December 11, 1997Date of Patent: September 7, 1999Assignee: General Electric CompanyInventors: Raphael Mestanza, Patrick Joseph McCloskey, Theodorus Lambertus Hoeks, Adrianus Alphonsus Kusters, Pin-Pin Wu, Ye-Gang Lin