Patents by Inventor Timothy D. Dunbar

Timothy D. Dunbar 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: 11844849
    Abstract: Dental compositions and methods of formulating a dental composition are described. In one embodiment, the dental composition comprises a polymerizable resin comprising one or more ethylenically unsaturated monomers or oligomers and nanoparticles. The nanoparticles have a refractive index of at least 1.600 and an average discrete or aggregate particle size of no greater than 100 nm. The dental composition further comprises inorganic metal oxide filler having a discrete or aggregate average particle size of at least 200 nm. The nanoparticles are present at a concentration to provide a refractive index differential between the cured polymerizable resin and inorganic metal oxide filler such that the contrast ratio of the dental composition is at least 40.
    Type: Grant
    Filed: January 7, 2022
    Date of Patent: December 19, 2023
    Assignee: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Bradley D. Craig, Timothy D. Dunbar, Karsten Dede, Adrian S. Eckert, Ahmed S. Abuelyaman, Gregory A. Kobussen, Christoph H. Thalacker, Paul J. Homnick
  • Patent number: 11553996
    Abstract: A radiation curable composition including at least one radiation hardenable component, a photo-initiator, and a filler material having a population of particulates in an amount greater than or equal to 50% by weight of the printable composition. The population of particulates exhibits a median diameter (D50) of greater than or equal to 0.3 micrometer on a volume-average basis as determined using the Particle Size Test Method, and the radiation curable composition exhibits a viscosity of less than or equal to 150 Pa s when measured using the Viscosity Test Method. A method, apparatus, and systems for producing composite articles by selectively exposing a portion of the radiation curable composition to a source of actinic radiation to at least partially cure the exposed portion of the radiation curable composition, thereby forming a hardened layer, preferably by an additive manufacturing process such as stereophotolithography, are also described. The composite articles may include composite dental restorations.
    Type: Grant
    Filed: August 22, 2018
    Date of Patent: January 17, 2023
    Assignee: 3M Innovative Properties Company
    Inventors: Zeba Parkar, James D. Hansen, Tianyu Wu, Carsten Franke, Timothy D. Dunbar, Gregory A. Kobussen, Ahmed S. Abuelyaman, Bradley D. Craig
  • Patent number: 11377573
    Abstract: A curable composition that includes a urethane multifunctional (meth)acrylate, an inorganic filler having a primary particle dimension of at least 200 nm, a photoinitiator system that can be activated by electromagnetic radiation in the range of 340-550 nm, a reactive diluent, and a reinforcing silica having a primary particle dimension of 100 nm of less. The sum of the absolute value of the difference in the refractive index of the filler and the refractive index of the composition cured without filler plus the birefringence of the filler is 0.054 or less, i.e. 0.054?|nfiller?nmatrix|+?filler, where nfiller is the refractive index of the filler, nmatrix is the refractive index of the composition cured without filler, and ?filler is the birefringence of the filler.
    Type: Grant
    Filed: September 5, 2019
    Date of Patent: July 5, 2022
    Assignee: 3M Innovative Properties Company
    Inventors: Ying Lin, Sheng Ye, Timothy D. Dunbar, Bradley D. Craig, Dong-Wei Zhu, Matthew J. Kryger, Richard J. Pokorny, Michael A. Kropp
  • Publication number: 20220125687
    Abstract: Dental compositions and methods of formulating a dental composition are described. In one embodiment, the dental composition comprises a polymerizable resin comprising one or more ethylenically unsaturated monomers or oligomers and nanoparticles. The nanoparticles have a refractive index of at least 1.600 and an average discrete or aggregate particle size of no greater than 100 nm. The dental composition further comprises inorganic metal oxide filler having a discrete or aggregate average particle size of at least 200 nm. The nanoparticles are present at a concentration to provide a refractive index differential between the cured polymerizable resin and inorganic metal oxide filler such that the contrast ratio of the dental composition is at least 40.
    Type: Application
    Filed: January 7, 2022
    Publication date: April 28, 2022
    Inventors: Bradley D. Craig, Timothy D. Dunbar, Karsten Dede, Adrian S. Eckert, Ahmed S. Abuelyaman, Gregory A. Kobussen, Christoph H. Thalacker, Paul J. Homnick
  • Patent number: 11246808
    Abstract: Dental compositions and methods of formulating a dental composition are described. In one embodiment, the dental composition comprises a polymerizable resin comprising one or more ethylenically unsaturated monomers or oligomers and nano-particles. The nanoparticles have a refractive index of at least 1.600 and an average discrete or aggregate particle size of no greater than 100 nm. The dental composition further comprises inorganic metal oxide filler having a discrete or aggregate average particle size of at least 200 nm. The nanoparticles are present at a concentration to provide a refractive index differential between the cured polymerizable resin and inorganic metal oxide filler such that the contrast ratio of the dental composition is at least 40.
    Type: Grant
    Filed: February 1, 2017
    Date of Patent: February 15, 2022
    Assignee: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Bradley D. Craig, Timothy D. Dunbar, Karsten Dede, Adrian S. Eckert, Ahmed S. Abuelyaman, Gregory A. Kobussen, Christoph H. Thalacker, Paul J. Homnick
  • Publication number: 20210198520
    Abstract: A curable composition that includes a urethane multifunctional (meth)acrylate, an inorganic filler having a primary particle dimension of at least 200 nm, a photoinitiator system that can be activated by electromagnetic radiation in the range of 340-550 nm, a reactive diluent, and a reinforcing silica having a primary particle dimension of 100 nm of less. The sum of the absolute value of the difference in the refractive index of the filler and the refractive index of the composition cured without filler plus the birefringence of the filler is 0.054 or less, i.e. 0.054?|nfiller?nmatrix|+?filler, where nfiller is the refractive index of the filler, nmatrix is the refractive index of the composition cured without filler, and ?filler is the birefringence of the filler.
    Type: Application
    Filed: September 5, 2019
    Publication date: July 1, 2021
    Inventors: Ying Lin, Sheng Ye, Timothy D. Dunbar, Bradley D. Craig, Dong-Wei Zhu, Matthew J. Kryger, Richard J. Pokorny, Michael A. Kropp
  • Publication number: 20200197138
    Abstract: A radiation curable composition including at least one radiation hardenable component, a photo-initiator, and a filler material having a population of particulates in an amount greater than or equal to 50% by weight of the printable composition. The population of particulates exhibits a median diameter (D50) of greater than or equal to 0.3 micrometer on a volume-average basis as determined using the Particle Size Test Method, and the radiation curable composition exhibits a viscosity of less than or equal to 150 Pa s when measured using the Viscosity Test Method. A method, apparatus, and systems for producing composite articles by selectively exposing a portion of the radiation curable composition to a source of actinic radiation to at least partially cure the exposed portion of the radiation curable composition, thereby forming a hardened layer, preferably by an additive manufacturing process such as stereophotolithography, are also described. The composite articles may include composite dental restorations.
    Type: Application
    Filed: August 22, 2018
    Publication date: June 25, 2020
    Inventors: Zeba Parkar, James D. Hansen, Tianyu Wu, Carsten Franke, Timothy D. Dunbar, Gregory A. Kobussen, Ahmed S. Abuelyaman, Bradley D. Craig
  • Publication number: 20190038516
    Abstract: Dental compositions and methods of formulating a dental composition are described. In one embodiment, the dental composition comprises a polymerizable resin comprising one or more ethylenically unsaturated monomers or oligomers and nano-particles. The nanoparticles have a refractive index of at least 1.600 and an average discrete or aggregate particle size of no greater than 100 nm. The dental composition further comprises inorganic metal oxide filler having a discrete or aggregate average particle size of at least 200 nm. The nanoparticles are present at a concentration to provide a refractive index differential between the cured polymerizable resin and inorganic metal oxide filler such that the contrast ratio of the dental composition is at least 40.
    Type: Application
    Filed: February 1, 2017
    Publication date: February 7, 2019
    Inventors: Bradley D. Craig, Timothy D. Dunbar, Karsten Dede, Adrian S. Eckert, Ahmed S. Abuelyaman, Gregory A. Kobussen, Christoph H. Thalacker, Paul J. Homnick
  • Patent number: 10028894
    Abstract: The invention relates to a curable composition for dental use comprising polyoxymetalates and/or derivatives thereof in an amount of at least about 5 wt.-% with respect to the weight of the composition.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: July 24, 2018
    Assignee: 3M Innovative Properties Company
    Inventors: Adam D. Miller, Matthew H. Frey, Timothy D. Dunbar, Henry Loll, Christoph Thalacker
  • Publication number: 20160199267
    Abstract: The invention relates to a curable composition for dental use comprising polyoxymetalates and/or derivatives thereof in an amount of at least about 5 wt.-% with respect to the weight of the composition.
    Type: Application
    Filed: September 4, 2014
    Publication date: July 14, 2016
    Inventors: Adam D. Miller, Matthew H. Frey, Timothy D. Dunbar, Henry Loll, Christoph Thalacker
  • Patent number: 9320685
    Abstract: Dental compositions are described comprising an addition-fragmentation agent of the formula: wherein R1, R2 and R3 are each independently Zm-Q-, a (hetero)alkyl group or a (hetero)aryl group with the proviso that at least one of R1, R2 and R3 is Zm-Q-; Q is a linking group have a valence of m+1; Z is an ethylenically unsaturated polymerizable group; m is 1 to 6; each X1 is independently —O— or —NR4—, where R4 is H or C1-C4 alkyl; and n is 0 or 1. Also described are dental articles prepared from a dental composition comprising an addition-fragmentation agent and methods of treating a tooth surface.
    Type: Grant
    Filed: May 8, 2015
    Date of Patent: April 26, 2016
    Assignee: 3M Innovative Properties Company
    Inventors: William H. Moser, Guy D. Joly, Larry R. Krepski, Babu N. Gaddam, Ahmed S. Abuelyaman, Bradley D. Craig, Timothy D. Dunbar, Chuntao Cao, Joel D. Oxman, Afshin Falsafi, Hoa T. Bui
  • Publication number: 20150238389
    Abstract: Dental compositions are described comprising an addition-fragmentation agent of the formula: wherein R1, R2 and R3 are each independently Zm-Q-, a (hetero)alkyl group or a (hetero)aryl group with the proviso that at least one of R1, R2 and R3 is Zm-Q-; Q is a linking group have a valence of m+1; Z is an ethylenically unsaturated polymerizable group; m is 1 to 6; each X1 is independently —O— or —NR4—, where R4 is H or C1-C4 alkyl; and n is 0 or 1. Also described are dental articles prepared from a dental composition comprising an addition-fragmentation agent and methods of treating a tooth surface.
    Type: Application
    Filed: May 8, 2015
    Publication date: August 27, 2015
    Inventors: William H. Moser, Guy D. Joly, Larry R. Krepski, Babu N. Gaddam, Ahmed S. Abuelyaman, Bradley D. Craig, Timothy D. Dunbar, Chuntao Cao, Joel D. Oxman, Afshin Falsafi, Hoa T. Bui
  • Patent number: 9072664
    Abstract: Powder drug compositions exhibiting improved flow properties are manufactured by spraying a suspension of surface-modified nanoparticles having an average particle size diameter of less than 100 nm in a dryable liquid carrier onto particles of a powder ingredient of a drug composition. The liquid carrier is rapidly dried so as to leave the nanoparticles on the powder. Other ingredients of the powder drug composition can also be added.
    Type: Grant
    Filed: April 17, 2009
    Date of Patent: July 7, 2015
    Assignee: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Stephen W. Stein, Michael W. Mueting, Timothy D. Dunbar
  • Patent number: 9056043
    Abstract: Dental compositions are described comprising an addition-fragmentation agent comprising at least one ethylenically unsaturated terminal group and a backbone unit comprising an ?,?-unsaturated carbonyl; at least one monomer comprising at least two ethylenically unsaturated group; and inorganic oxide filler. The addition-fragmentation agent is preferably free-radically cleavable. The addition-fragmentation agent preferably comprises at least two ethylenically unsaturated terminal groups, such as (meth)acTylate groups. In some embodiments, the addition-fragmentation agent has the formula: wherein R1, R2 and R3 are each independently Zm, -Q-, a (hetero)alkyl group or a (hetero)aryl group with the proviso that at least one of R1, R2 and R3 is Zm-Q-; Q is a linking group have a valence of m+1; Z is an ethylenically unsaturated polymerizable group; m is 1 to 6; each X1 is independently —O— or —NR4—, where R4 is H or C1-C4 alkyl; and n is 0 or 1.
    Type: Grant
    Filed: February 8, 2012
    Date of Patent: June 16, 2015
    Assignee: 3M Innovative Properties Company
    Inventors: Guy D. Joly, Larry R. Krepski, Babu N. Gaddam, Ahmed S. Abuelyaman, Bradley D. Craig, Timothy D. Dunbar, Chuntao Cao, Joel D. Oxman, Afshin Falsafi, William H. Moser, Hoa T. Bui
  • Patent number: 9012531
    Abstract: Hardenable compositions are described comprising at least one multifunctional ethylenically unsaturated isocyanurate monomer and at least one multifunctional ethylenically unsaturated tricyclodecane monomer. In favored embodiments, the compositions further comprise filler and are suitable dental restorations.
    Type: Grant
    Filed: February 6, 2012
    Date of Patent: April 21, 2015
    Assignee: 3M Innovative Properties Company
    Inventors: Ahmed S. Abuelyaman, Adrian S. Eckert, Sumita B. Mitra, Timothy D. Dunbar, Bradley D. Craig, Chuntao Cao
  • Patent number: 8834832
    Abstract: A process comprises (a) combining (1) at least one base and (2) at least one metal carboxylate salt comprising (i) a metal cation selected from metal cations that form amphoteric metal oxides or oxyhydroxides and (ii) a lactate or thiolactate anion, or metal carboxylate salt precursors comprising (i) at least one metal salt comprising the metal cation and a non-interfering anion and (ii) lactic or thiolactic acid, a lactate or thiolactate salt of a non-interfering, non-metal cation, or a mixture thereof; and (b) allowing the base and the metal carboxylate salt or metal carboxylate salt precursors to react.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: September 16, 2014
    Assignee: 3M Innovative Properties Company
    Inventor: Timothy D. Dunbar
  • Publication number: 20140220512
    Abstract: Hardenable compositions are described comprising at least one multifunctional ethylenically unsaturated isocyanurate monomer and at least one multifunctional ethylenically unsaturated tricyclodecane monomer. In favored embodiments, the compositions further comprise filler and are suitable dental restorations.
    Type: Application
    Filed: February 6, 2012
    Publication date: August 7, 2014
    Applicant: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Ahmed S. Abuelyaman, Adrian S. Eckert, Sumita B. Mitra, Timothy D. Dunbar, Bradley D. Craig, Chuntao Cao
  • Publication number: 20130316307
    Abstract: Dental compositions are described comprising an addition-fragmentation agent comprising at least one ethylenically unsaturated terminal group and a backbone unit comprising an ?,?-unsaturated carbonyl; at least one monomer comprising at least two ethylenically unsaturated group; and inorganic oxide filler. The addition-fragmentation agent is preferably free-radically cleavable. The addition-fragmentation agent preferably comprises at least two ethylenically unsaturated terminal groups, such as (meth)acTylate groups. In some embodiments, the addition-fragmentation agent has the formula: wherein R1, R2 and R3 are each independently Zm, -Q-, a (hetero)alkyl group or a (hetero)aryl group with the proviso that at least one of R1, R2 and R3 is Zm-Q-; Q is a linking group have a valence of m+1; Z is an ethylenically unsaturated polymerizable group; m is 1 to 6; each X1 is independently —O— or —NR4—, where R4 is H or C1-C4 alkyl; and n is 0 or 1.
    Type: Application
    Filed: February 8, 2012
    Publication date: November 28, 2013
    Applicant: 3M INNOVATIVE PROPERTIES COMPANY
    Inventors: Guy D. Joly, Larry R. Krepski, Babu N. Gaddam, Ahmed S. Abuelyaman, Bradley D. Craig, Timothy D. Dunbar, Chuntao Cao, Joel D. Oxman, Afshin Falsafi, William H. Moser, Hoa T. Bui
  • Patent number: 8383682
    Abstract: A composition comprises surface-modified nanoparticles of at least one amphoteric metal oxide or oxyhydroxide. The nanoparticles bear, on at least a portion of their surfaces, a surface modification comprising (i) at least one surface modifier selected from lactate, thiolactate, and mixtures thereof, and (ii) at least one surface modifier selected from halide, nitrate, acetate, carbonate, formate, propionate, sulfate, bromate, perchlorate, tribromoacetate, trichloroacetate, trifluoroacetate, carboxylate comprising from one to about four alkyleneoxy moieties, chlorate, and mixtures thereof.
    Type: Grant
    Filed: December 16, 2008
    Date of Patent: February 26, 2013
    Assignee: 3M Innovative Properties Company
    Inventor: Timothy D. Dunbar
  • Patent number: 8236277
    Abstract: A process comprises (a) combining (1) at least one base and (2) at least one metal carboxylate salt comprising (i) a metal cation selected from metal cations that form amphoteric metal oxides or oxyhydroxides and (ii) a carboxylate anion comprising from one to four alkyleneoxy moieties, or metal carboxylate salt precursors comprising (i) at least one metal salt comprising the metal cation and a non-interfering anion and (ii) at least one carboxylic acid comprising from one to four alkyleneoxy moieties, at least one salt of the carboxylic acid and a non-interfering, non-metal cation, or a mixture thereof; and (b) allowing the base and the metal carboxylate salt or metal carboxylate salt precursors to react.
    Type: Grant
    Filed: December 18, 2007
    Date of Patent: August 7, 2012
    Assignee: 3M Innovative Properties Company
    Inventor: Timothy D. Dunbar