US20060189113A1 - Metal nanoparticle compositions - Google Patents

Metal nanoparticle compositions Download PDF

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Publication number
US20060189113A1
US20060189113A1 US11331211 US33121106A US2006189113A1 US 20060189113 A1 US20060189113 A1 US 20060189113A1 US 11331211 US11331211 US 11331211 US 33121106 A US33121106 A US 33121106A US 2006189113 A1 US2006189113 A1 US 2006189113A1
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composition
metal
ink
present
surface
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Abandoned
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US11331211
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Karel Vanheusden
Klaus Kunze
Hyungrak Kim
Aaron Stump
Allen Schult
Mark Hampden-Smith
Chuck Edwards
Anthony James
James Caruso
Toivo Kodas
Scott Haubrich
Mark Kowalski
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Cabot Corp
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Cabot Corp
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER
    • B22F1/00Special treatment of metallic powder, e.g. to facilitate working, to improve properties; Metallic powders per se, e.g. mixtures of particles of different composition
    • B22F1/0003Metallic powders per se; Mixtures of metallic powders; Metallic powders mixed with a lubricating or binding agent
    • B22F1/0007Metallic powder characterised by its shape or structure, e.g. fibre structure
    • B22F1/0011Metallic powder characterised by size or surface area only
    • B22F1/0018Nanometer sized particles
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER
    • B22F1/00Special treatment of metallic powder, e.g. to facilitate working, to improve properties; Metallic powders per se, e.g. mixtures of particles of different composition
    • B22F1/0003Metallic powders per se; Mixtures of metallic powders; Metallic powders mixed with a lubricating or binding agent
    • B22F1/0007Metallic powder characterised by its shape or structure, e.g. fibre structure
    • B22F1/0011Metallic powder characterised by size or surface area only
    • B22F1/0018Nanometer sized particles
    • B22F1/0022Dispersions or suspensions thereof
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER
    • B22F9/00Making metallic powder or suspensions thereof
    • B22F9/16Making metallic powder or suspensions thereof using chemical processes
    • B22F9/18Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
    • B22F9/24Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B82NANOTECHNOLOGY
    • B82YSPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00Nanotechnology for materials or surface science, e.g. nanocomposites
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; MISCELLANEOUS COMPOSITIONS; MISCELLANEOUS APPLICATIONS OF MATERIALS
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D11/00Inks
    • C09D11/02Printing inks
    • C09D11/10Printing inks based on artificial resins
    • C09D11/101Inks specially adapted for printing processes involving curing by wave energy or particle radiation, e.g. with UV-curing following the printing
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; MISCELLANEOUS COMPOSITIONS; MISCELLANEOUS APPLICATIONS OF MATERIALS
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D11/00Inks
    • C09D11/30Inkjet printing inks
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; MISCELLANEOUS COMPOSITIONS; MISCELLANEOUS APPLICATIONS OF MATERIALS
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D11/00Inks
    • C09D11/30Inkjet printing inks
    • C09D11/38Inkjet printing inks characterised by non-macromolecular additives other than solvents, pigments or dyes
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B3/00Extraction of metal compounds from ores or concentrates by wet processes
    • C22B3/20Treatment or purification of solutions, e.g. obtained by leaching
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01BCABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/20Conductive material dispersed in non-conductive organic material
    • H01B1/22Conductive material dispersed in non-conductive organic material the conductive material comprising metals or alloys
    • HELECTRICITY
    • H01BASIC ELECTRIC ELEMENTS
    • H01LSEMICONDUCTOR DEVICES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H01L21/00Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
    • H01L21/02Manufacture or treatment of semiconductor devices or of parts thereof
    • H01L21/04Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer, carrier concentration layer
    • H01L21/18Manufacture or treatment of semiconductor devices or of parts thereof the devices having at least one potential-jump barrier or surface barrier, e.g. PN junction, depletion layer, carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic System or AIIIBV compounds with or without impurities, e.g. doping materials
    • H01L21/28Manufacture of electrodes on semiconductor bodies using processes or apparatus not provided for in H01L21/20 - H01L21/268
    • H01L21/283Deposition of conductive or insulating materials for electrodes conducting electric current
    • H01L21/288Deposition of conductive or insulating materials for electrodes conducting electric current from a liquid, e.g. electrolytic deposition
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K1/00Printed circuits
    • H05K1/02Details
    • H05K1/09Use of materials for the metallic pattern or other conductive pattern
    • H05K1/092Dispersed materials, e.g. conductive pastes or inks
    • H05K1/097Inks comprising nanoparticles, i.e. inks which are sinterable at low temperatures
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22FWORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER
    • B22F2998/00Supplementary information concerning processes or compositions relating to powder metallurgy
    • B22F2998/10Processes characterised by the sequence of their steps
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B11/00Obtaining noble metals
    • C22B11/04Obtaining noble metals by wet processes
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22BPRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B23/00Obtaining nickel or cobalt
    • C22B23/04Obtaining nickel or cobalt by wet processes
    • C22B23/0453Treatment or purification of solutions, e.g. obtained by leaching
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2203/00Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
    • H05K2203/01Tools for processing; Objects used during processing
    • H05K2203/0104Tools for processing; Objects used during processing for patterning or coating
    • H05K2203/013Inkjet printing, e.g. for printing insulating material or resist
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/10Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
    • H05K3/12Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using thick film techniques, e.g. printing techniques to apply the conductive material or similar techniques for applying conductive paste or ink patterns
    • H05K3/1241Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using thick film techniques, e.g. printing techniques to apply the conductive material or similar techniques for applying conductive paste or ink patterns by ink-jet printing or drawing by dispensing
    • H05K3/125Apparatus or processes for manufacturing printed circuits in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern using thick film techniques, e.g. printing techniques to apply the conductive material or similar techniques for applying conductive paste or ink patterns by ink-jet printing or drawing by dispensing by ink-jet printing
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Process efficiency
    • Y02P10/21Process efficiency by recovering materials
    • Y02P10/212Recovering metals from waste
    • Y02P10/234Recovering metals from waste by hydro metallurgy
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00Nanotechnology
    • Y10S977/70Nanostructure
    • Y10S977/773Nanoparticle, i.e. structure having three dimensions of 100 nm or less
    • Y10S977/775Nanosized powder or flake, e.g. nanosized catalyst
    • Y10S977/777Metallic powder or flake
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S977/00Nanotechnology
    • Y10S977/84Manufacture, treatment, or detection of nanostructure
    • Y10S977/895Manufacture, treatment, or detection of nanostructure having step or means utilizing chemical property
    • Y10S977/896Chemical synthesis, e.g. chemical bonding or breaking

Abstract

A metal nanoparticle composition for the fabrication of conductive features. The metal nanoparticle composition advantageously has a low viscosity permitting deposition of the composition by direct-write tools. The metal nanoparticle composition advantageously also has a low conversion temperature, permitting its deposition and conversion to an electrical feature on polymeric substrates.

Description

    CROSS-REFERENCE TO RELATED APPLICATIONS
  • [0001]
    This application claims the benefit of U.S. Provisional Application Serial Nos. 60/643,577; 60/643,629; and 60/643,378, all filed on Jan. 14, 2005, the entireties of which are all incorporated herein by reference.
  • BACKGROUND OF THE INVENTION
  • [0002]
    1. Field of the Invention
  • [0003]
    The present invention relates to metal nanoparticle compositions that are useful for the production of electrically conductive features. The compositions may advantageously be deposited on a variety of substrates and processed into electrically conductive features at low temperatures. The compositions can also have a viscosity which allows the deposition of the compositions using direct-write tools, such as ink-jet devices.
  • [0004]
    2. Discussion of Background Information
  • [0005]
    The electronics, display and energy industries rely on the formation of coatings and patterns of conductive materials to form circuits on organic and inorganic substrates. The primary methods for generating these patterns are screen printing for features larger than about 100 μm and thin film and etching methods for features smaller than about 100 μm. Other subtractive methods to attain fine feature sizes include the use of photo-patternable pastes and laser trimming.
  • [0006]
    One consideration with respect to patterning of conductors is cost. Non-vacuum, additive methods generally entail lower costs than vacuum and subtractive approaches. Some of these printing approaches utilize high viscosity flowable liquids. Screen-printing, for example, uses flowable mediums with viscosities of thousands of centipoise. At the other extreme, low viscosity compositions can be deposited by methods such as ink-jet printing. However, low viscosity compositions are not as well developed as the high viscosity compositions.
  • [0007]
    Ink-jet printing of conductors has been explored, but the approaches to date have been inadequate for producing well-defined features with good electrical properties, particularly at relatively low temperatures.
  • [0008]
    There exists a need for compositions for the fabrication of conductive features for use in electronics, displays, and other applications. Further, there is a need for compositions that have low processing temperatures to allow deposition onto organic substrates and subsequent thermal treatment. It would also be advantageous if the compositions could be deposited with a fine feature size, such as not greater than about 100 μm, while still providing electronic features with adequate electrical and mechanical properties.
  • [0009]
    An advantageous metal nanoparticle composition and its associated deposition technique for the fabrication of electrically conductive features would combine a number of attributes. The conductive feature would have high conductivity, preferably close to that of the pure bulk metal. The processing temperature would be low enough to allow formation of conductors on a variety of organic substrates (polymers). The deposition technique would allow deposition onto surfaces that are non-planar (e.g., not flat). The conductor would also have good adhesion to the substrate. The composition would desirably be inkjet printable, allowing the introduction of cost-effective material deposition for production of devices such as flat panel displays (PDP, AMLCD, OLED). The composition would desirably also be flexo, gravure, or offset printable, again enabling lower cost and higher yield production processes as compared to screen printing.
  • [0010]
    Further, there is a need for electronic circuit elements and complete electronic circuits fabricated on inexpensive, thin and/or flexible substrates, such as paper, using high volume printing techniques such as reel-to-reel printing. Recent developments in organic thin film transistor (TFT) technology and organic light emitting device (OLED) technology have accelerated the need for complimentary circuit elements that can be written directly onto low cost substrates. Such elements include conductive interconnects, electrodes, conductive contacts and via fills.
  • SUMMARY OF THE INVENTION
  • [0011]
    The present invention is directed to metal nanoparticle compositions that can be deposited onto a substrate using, for example, direct-write methods such as ink-jet deposition. The metal nanoparticle compositions preferably exhibit a low processing (curing) temperature, thereby permitting the formation of electrically conductive features on a variety of substrates, including organic substrates. The metal nanoparticle compositions can be deposited onto a substrate and processed by heating and/or irradiation to form features with good electrical and/or mechanical properties.
  • [0012]
    In particular, the present invention provides a composition which is suitable for the fabrication of an electrically conductive feature by using a direct-write tool. The composition comprises metal nanoparticles which carry thereon a substance that is capable of substantially preventing an agglomeration of the nanoparticles (hereafter referred to as “anti-agglomeration substance”) and a vehicle that is capable of forming a dispersion with the metal nanoparticles.
  • [0013]
    The present invention also provides a composition for the fabrication of a conductive feature by ink-jet printing, which composition comprises at least about 5 weight percent of metal nanoparticles which carry thereon an organic substance that is capable of substantially preventing an agglomeration of the nanoparticles, and a vehicle that comprises a mixture of organic solvents. The composition has a surface tension at 20° C. of from about 20 dynes/cm to about 40 dynes/cm and a viscosity at 20° C. of from about 5 cP to about 15 cP.
  • [0014]
    The present invention also provides a composition for providing a substrate with a metal structure (e.g., a discrete feature, a metal layer, etc.). The composition comprises at least about 10 weight percent of substantially non-agglomerated metal nanoparticles which have adsorbed thereon a polymer, and a vehicle which comprises an organic solvent that is capable of dissolving the polymer. The composition has a surface tension at 20° C. of not higher than about 60 dynes/cm and a viscosity at 20° C. of not higher than about 30 cP.
  • [0015]
    The present invention further provides a composition for ink-jet printing, which composition comprises metal nanoparticles and is capable of being deposited on a substrate by ink-jet printing of the composition in not more than two passes (e.g., a single pass) of an ink-jet printing head as a line that can be rendered electrically conductive.
  • [0016]
    The present invention also provides a printed metallic feature which comprises a metal and a vinyl pyrrolidone polymer in a weight ratio of from about 100:1 to about 5:1.
  • [0017]
    Further, the present invention provides a substrate which has a metal structure thereon. The metal structure comprises. voids that are at least partially filled with an organic polymer, e.g., a vinyl pyrrolidone polymer.
  • [0018]
    The present invention also provides a method for the fabrication of a conductive feature on a substrate, which method comprises forming the feature by applying a composition according to the present invention to the substrate and subjecting the feature to heat and/or radiation and/or pressure to render the feature electrically conductive.
  • [0019]
    The present invention also provides a method for the fabrication of a conductive feature on a substrate. The method comprises
      • (a) depositing on the substrate a composition comprising (i) metal nanoparticles which carry thereon a substance that is capable of substantially preventing an agglomeration of the nanoparticles and (ii) a liquid vehicle that comprises a solvent that is capable of dissolving the agglomeration-preventing substance; and
      • (b) converting the deposited composition to a conductive feature by subjecting it to heat and/or pressure and/or radiation.
  • [0022]
    The present invention also provides a further method for the fabrication of a conductive feature on a substrate. This method comprises
      • (a) ink-jet printing on the substrate a composition comprising (i) at least about 10% by weight of substantially non-agglomerated silver nanoparticles which carry thereon a vinyl pyrrolidone polymer and (ii) a liquid vehicle; and
      • (b) converting the printed composition to a conductive feature by subjecting the composition to heat and/or pressure and/or radiation.
  • [0025]
    The present invention also provides the use of a composition for the fabrication of an electrically conductive feature, wherein the composition comprises (a) metal nanoparticles which carry thereon a substance that is capable of substantially preventing an agglomeration of the nanoparticles and (b) a vehicle that is capable of forming a dispersion with the metal nanoparticles, the composition being suitable for the fabrication of an electrically conductive feature by using a direct-write tool.
  • [0026]
    The present invention also provides a security feature which comprises a metal and is both semi-transparent and reflective in the visible light range. In one embodiment, the security feature is ink-jet printed and may additionally be luminescent. In another embodiment, when the security feature is ink-jet printed, the feature is made by a process which comprises ink-jet printing a composition which comprises substantially non-agglomerated metal nanoparticles on a substrate.
  • [0027]
    The present inventiton also provides an optically variable security feature, wherein the security feature comprises a metal and is ink-jet printed. In one embodiment, the feature is made by a process which comprises ink-jet printing a composition which comprises substantially non-agglomerated metal nanoparticles on a substrate.
  • [0028]
    The present invention also provides a security feature which comprises a metal pattern, wherein the metal pattern is made by a process which comprises ink-jet printing. In one embodiment, the metal pattern is made by a process which comprises ink-jet printing a composition which comprises substantially non-agglomerated metal nanoparticles on a substrate.
  • [0029]
    The present invention also provides an ink, comprising: liquid vehicle; and metallic nanoparticles in an amount greater than about 40 weight percent, based on the total weight of the ink.
  • [0030]
    The present invention also provides a process for making an ink-jet printable ink for the fabrication of electric and electronic devices. The process comprises combining metal nanoparticles which carry thereon an anti-agglomeration substance with at a liquid vehicle to form a dispersion having a nanoparticle concentration of at least about 5% by weight and a surface tension at 20° C. of from about 20 dynes/cm to about 60 dynes/cm and a viscosity at 20° C. of from about 3 cP to about 15 cP.
  • [0031]
    The metal nanoparticle compositions of the present invention can, for example, be utilized to form complex, high precision circuitry having good electrical properties. For example, the compositions and methods of the present invention can be utilized to form conductive features on a substrate, wherein the features have a feature size (i.e., average width of the smallest dimension) of not greater than about 200 micrometers (μm), e.g., not greater than about 150 μm, not greater than about 100 μm, not greater than about 75 μm, not greater than about 50 μm, or not greater than about 25 μm.
  • [0032]
    The electrically conductive features formed according to the present invention can have good electrical properties. By way of non-limiting example, they may have a resistivity that is not greater than about 30 times the resistivity of the pure bulk metal, e.g., not greater than about 20 times, not greater than about 10 times, not greater than about 5 times, or not greater than about 3 times the resistivity of the pure bulk metal.
  • [0033]
    The method for forming the electronic features according to the present invention can also involve a relatively low processing temperature (i.e., the minimum temperature that is required to impart electrical conductivity to a deposited composition). In one aspect, the processing temperature may be not greater than about 250° C., e.g., not greater than about 225° C., not greater than about 200° C., or not greater than about 185° C. In some aspects, the processing temperature may be not greater than about 150° C., e.g., not greater than about 125° C., or not greater than about 100° C.
  • BRIEF DESCRIPTION OF THE DRAWING
  • [0034]
    The present invention will be better understood in view of the following non-limiting FIGURE, wherein:
  • [0035]
    FIG. 1 illustrates continuous feature ink-jet printing by adequate drop placement, taking into account ink drop volume and wetting behavior on the substrate.
  • DETAILED DESCRIPTION OF THE PRESENT INVENTION
  • [0036]
    Nanoparticles
  • [0037]
    The metal of the nanoparticles of the compositions of the present invention preferably is a metal which exhibits a low bulk resistivity such as, e.g., a bulk resistivity of less than about 15 micro-Ω cm, e.g., less than about 10 micro-Ω cm, or less than about 5 micro-Ω cm. Non-limiting examples of metals for use in the present invention include transition metals as well as main group metals such as, e.g., silver, gold, copper, nickel, cobalt, palladium, platinum, indium, tin, zinc, titanium, chromium, tantalum, tungsten, iron, rhodium, iridium, ruthenium, osmium and lead. Non-limiting examples of preferred metals for use in the present invention include silver, gold, copper, nickel, cobalt, rhodium, palladium and platinum. Silver, copper and nickel are particularly preferred metals for the purposes of the present invention. Silver is the most preferred metal.
  • [0038]
    The compositions of the present invention also may comprise mixtures of two or more different metal nanoparticles and/or may comprise nanoparticles wherein two or more metals are present in a single nanoparticle, for example, in the form of an alloy or a mixture of these metals. Non-limiting examples of alloys include Ag/Ni, Ag/Cu, Pt/Cu, Ru/Pt, fr/Pt and Ag/Co. Also, the nanoparticles may have a core-shell structure made of two different metals such as, e.g., a core of silver and a shell of nickel (e.g. a silver core having a diameter of about 20 nm surrounded by an about 15 nm thick nickel shell).
  • [0039]
    The composition of the present invention may comprise metallic nanoparticles in an amount greater than about 50 weight percent, based on the total weight of the composition. In another embodiment, the composition of the present invention may comprise metallic nanoparticles in an amount greater than about 60 weight percent, based on the total weight of the composition. In yet another embodiment, the composition of the present invention may comprise metallic nanoparticles in an amount greater than about 40 weight percent and less than about 90 weight percent, based on the total weight of the composition. In still another embodiment, the composition of the present invention may comprise metallic nanoparticles in an amount from about 50 to about 80 weight percent, based on the total weight of the composition.
  • [0040]
    The anti-agglomeration substance that is present on the metal nanoparticles of the present invention is used to prevent a substantial agglomeration of the nanoparticles. Due to their small size and the high surface energy associated therewith, nanoparticles usually show a strong tendency to agglomerate and form larger secondary particles (agglomerates). The anti-agglomeration substance shields (e.g., sterically and/or through charge effects) the nanoparticles from each other to at least some extent and thereby substantially prevents a direct contact between individual nanoparticles. The anti-agglomeration substance is preferably adsorbed on the surface of the metal nanoparticles. The term “adsorbed” as used herein includes any kind of interaction between the anti-agglomeration substance and a nanoparticle surface (e.g., the metal atoms on the surface of a nanoparticle) that manifests itself in an at least (and preferably) weak bond between the anti-agglomeration substance and the surface of a nanoparticle. Preferably, the bond is a non-covalent bond, but still strong enough for the nanoparticle/anti-agglomeration substance combination to withstand a washing operation with a solvent that is capable of dissolving the anti-agglomeration substance. In other words, merely washing the metal nanoparticles with the solvent at room temperature will preferably not remove more than a minor amount (e.g., less than about 10%, less than about 5%, or less than about 1%) of the anti-agglomeration substance that is in intimate contact with (and (weakly) bonded to) the nanoparticle surface. Of course, any anti-agglomeration substance that is not in intimate contact with a nanoparticle surface but merely accompanies the bulk of the nanoparticles (e.g., as an impurity/contaminant), i.e., without any significant interaction therewith, will preferably be removable from the nanoparticles by washing the latter with a solvent for the anti-agglomeration substance.
  • [0041]
    The anti-agglomeration substance does not have to be present as a continuous coating (shell) on the entire surface of a metal nanoparticle. Rather, in order to prevent a substantial agglomeration of the nanoparticles it will often be sufficient for the anti-agglomeration substance to be present on only a part of the surface of a metal nanoparticle.
  • [0042]
    While the anti-agglomeration substance will usually be a single substance or at least comprise two or more substances of the same type, the present invention also contemplates the use of two or more different types of anti-agglomeration substances. For example, a mixture of two or more different low molecular weight compounds or a mixture of two or more different polymers may be used, as well as a mixture of one or more low molecular weight compounds and one or more polymers. The term “anti-agglomeration substance” as used herein includes all of these possibilities.
  • [0043]
    A preferred and non-limiting example of an anti-agglomeration substance for use in the present invention includes a substance that is capable of electronically interacting with a metal atom of a nanoparticle. Usually, a substance that is capable of this type of interaction will comprise one or more atoms (e.g., one or two atoms) with one or more free electron pairs such as, e.g., oxygen, nitrogen and sulfur. Particularly preferred anti-agglomeration substances comprise one or two O and/or N atoms (per monomer unit in the case of a polymer). The atoms with a free electron pair will usually be present in the substance in the form of a functional group such as, e.g., a hydroxy group, a carbonyl group, an ether group and an amino group, or as a constituent of a functional group that comprises one or more of these groups as a structural element thereof. Non-limiting examples of functional groups include —COO—, —O—CO—O—, —CO—O—CO—, —C—O—C—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical (e.g., an aliphatic or aromatic, unsubstituted or substituted radical comprising from about 1 to about 20 carbon atoms). Such functional groups may comprise the above (and other) structural elements as part of a cyclic structure (e.g., in the form of a cyclic ester, amide, anhydride, imide, carbonate, urethane, urea, and the like).
  • [0044]
    The anti-agglomeration substance may be inorganic or organic and may comprise a low molecular weight compound, preferably a low molecular weight organic compound, e.g., a compound having a molecular weight of not higher than about 500, more preferably not higher than about 300, and/or may comprise an oligomeric or polymeric, preferably organic compound having a (weight average) molecular weight of at least about 1,000, for example, at least about 3,000, at least about 5,000, or at least about 8,000, but preferably not higher than about 500,000, e.g., not higher than about 200,000, or not higher than about 100,000. By way of non-limiting example, in the case of polyvinylpyrrolidone, which is a non-limiting example of a preferred anti-agglomeration substance for use in the present invention, the preferred weight average molecular weight is in the range of from about 3,000 to about 60,000 and a particularly preferred average molecular weight is about 10,000.
  • [0045]
    In general, it is preferred for the anti-agglomeration substance to have a total of at least about 10 atoms per molecule which are selected from C, N and O, e.g., at least about 20 such atoms or at least about 50 such atoms. More preferably, the anti-agglomeration substance has a total of at least about 100 C, N and O atoms per molecule, e.g., at least about 200, at least about 300, or at least about 400 C, N and O atoms per molecule. In the case of polymers these numbers refer to the average per polymer molecule.
  • [0046]
    Non-limiting examples of the low molecular weight anti-agglomeration substance for use in the present invention include fatty acids, in particular, fatty acids having at least about 8 carbon atoms. Non-limiting examples of oligomers/polymers for use as the anti-agglomeration substance in the process of the present invention include homo- and copolymers (including polymers such as, e.g., random copolymers, block copolymers and graft copolymers) which comprise units of at least one monomer which comprises one or more O atoms and/or one or more N atoms. A non-limiting class of preferred polymers for use as anti-agglomeration substance in the present invention are polymers that form a dative bond to the metal nanoparticle surface. Such a dative bond is advantageously weak enough to break during heating after the nanoparticles have been applied to a substrate (e.g., by ink-jet printing). Thereby this dative bond will enable the nanoparticles to neck and form a conductive network, without the need to remove the polymer form the printed layer by combustion or volatilization. Another non-limiting class of preferred polymers for use in the present invention (which overlaps with the former class of preferred polymers) is constituted by polymers which comprise at least one monomer unit which includes at least two atoms which are selected from O and N atoms. Corresponding monomer units may, for example, comprise at least one hydroxyl group, carbonyl group, ether linkage and/or amino group and/or one or more structural elements of formula —COO—, —O—CO—O—, —CO—O—CO—, —C—O—C—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical (e.g., an aliphatic or aromatic, unsubstituted or substituted radical comprising from about 1 to about 20 carbon atoms).
  • [0047]
    Non-limiting examples of corresponding polymers include polymers which comprise one or more units derived from the following groups of monomers:
      • (a) monoethylenically unsaturated carboxylic acids of from about 3 to about 8 carbon atoms and salts thereof. This group of monomers includes, for example, acrylic acid, methacrylic acid, dimethylacrylic acid, ethacrylic acid, maleic acid, citraconic acid, methylenemalonic acid, allylacetic acid, vinylacetic acid, crotonic acid, fumaric acid, mesaconic acid and itaconic acid. The monomers of group (a) can be used either in the form of the free carboxylic acids or in partially or completely neutralized form. For the neutralization alkali metal bases, alkaline earth metal bases, ammonia or amines, e.g., sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, magnesium oxide, calcium hydroxide, calcium oxide, ammonia, triethylamine, methanolamine, diethanolamine, triethanolamine, morpholine, diethylenetriamine or tetraethylenepentamine may, for example, be used;
      • (b) the esters, amides, anhydrides and nitriles of the carboxylic acids stated under (a) such as, e.g., methyl acrylate, ethyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl acrylate, hydroxyethyl acrylate, 2- or 3-hydroxypropyl acrylate, 2- or 4-hydroxybutyl acrylate, hydroxyethyl methacrylate, 2- or 3-hydroxypropyl methacrylate, hydroxyisobutyl acrylate, hydroxyisobutyl methacrylate, monomethyl maleate, dimethyl maleate, monoethyl maleate, diethyl maleate, maleic anhydride, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, acrylamide, methacrylaamide, N,N-dimethylacrylamide, N-tert-butylacrylamide, acrylonitrile, methacrylonitrile, 2-dimethylaminoethyl acrylate, 2-dimethylaminoethyl methacrylate, 2-diethylaminoethyl acrylate, 2-diethylaminoethyl methacrylate and the salts of the last-mentioned monomers with carboxylic acids or mineral acids and the quatemized products;
      • (c) acrylamidoglycolic acid, vinylsulfonic acid, allylsulfonic acid, methallylsulfonic acid, styrenesulfonic acid, 3-sulfopropyl acrylate, 3-sulfopropyl methacrylate and acrylamidomethylpropanesulfonic acid and monomers containing phosphonic acid groups, such as, e.g., vinyl phosphate, allyl phosphate and acrylamidomethylpropanephosphonic acid; and esters, amides and anhydrides of these acids;
      • (d) N-vinyllactams such as, e.g., N-vinylpyrrolidone, N-vinyl-2-piperidone and N-vinylcaprolactam;
      • (e) vinyl acetal, vinyl butyral, vinyl alcohol and ethers and esters thereof (such as, e.g., vinyl acetate, vinyl propionate and methylvinylether), allyl alcohol and ethers and esters thereof, N-vinylimidazole, N-vinyl-2-methylimidazoline, and the hydroxystyrenes.
  • [0053]
    Corresponding polymers may also contain additional monomer units, for example, units derived from monomers without functional group, halogenated monomers, aromatic monomers etc. Non-limiting examples of such monomers include olefins such as, e.g., ethylene, propylene, the butenes, pentenes, hexenes, octenes, decenes and dodecenes, styrene, vinyl chloride, vinylidene chloride, tetrafluoroethylene, etc. Further, the polymers for use as adsorptive substance in the process of the present invention are not limited to addition polymers, but also comprise other types of polymers, for example, condensation polymers such as, e.g., polyesters, polyamides, polyurethanes and polyethers, as well as polysaccharides such as, e.g., starch, cellulose and derivatives thereof, etc.
  • [0054]
    Other non-limiting examples of polymers which are suitable for use as anti-agglomeration substance in the present invention are disclosed in e.g., U.S. Patent Application Publication 2004/0182533 A1, the entire disclosure whereof is expressly incorporated by reference herein.
  • [0055]
    Preferred polymers for use as anti-agglomeration substance in the present invention include those which comprise units derived from one or more N-vinylcarboxamides of formula (I)
    CH2═CH—NR3—CO—R4  (I)
    wherein R3 and R4 each independently represent hydrogen, optionally substituted alkyl (including cycloalkyl) or optionally substituted aryl (including alkaryl and aralkyl) or heteroaryl (e.g., C6-20 aryl such as phenyl, benzyl, tolyl and phenethyl, and C4-20 heteroaryl such as pyrrolyl, furyl, thienyl and pyridinyl).
  • [0056]
    R3 and R4 may, e.g., independently represent hydrogen or C1-12 alkyl, particularly C1-6 alkyl such as methyl and ethyl. R3 and R4 together may also form a straight or branched chain containing from about 2 to about 8, preferably from about 3 to about 6, particularly preferably from about 3 to about 5 carbon atoms, which chain links the N atom and the C atom to which R3 and R4 are bound to form a ring which preferably has about 4 to about 8 ring members. Optionally, one or more carbon atoms may be replaced by heteroatoms such as, e.g., oxygen, nitrogen or sulfur. Also optionally, the ring may contain a carbon-carbon double bond.
  • [0057]
    Non-limiting specific examples of R3 and R4 are methyl, ethyl, isopropyl, n-propyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-hexyl, n-heptyl, 2-ethylhexyl, n-octyl, n-decyl, n-undecyl, n-dodecyl, n-tetradecyl, n-hexadecyl, n-octadecyl and n-eicosyl. Non-limiting specific examples of R3 and R4 which together form a chain are 1,2-ethylene, 1,2-propylene, 1,3-propylene, 2- methyl-1,3-propylene, 2-ethyl-1,3-propylene, 1,4-butylene, 1,5-pentylene, 2-methyl- 1,5-pentylene, 1,6-hexylene and 3-oxa- 1,5-pentylene.
  • [0058]
    Non-limiting specific examples of N-vinylcarboxamides of formula (I) are N-vinylformamide, N-vinylacetamide, N-vinylpropionamide, N-vinylbutyramide, N-vinylisobutyramide, N-vinyl-2-ethylhexanamide, N-vinyldecanamide, N-vinyldodecanamide, N-vinylstearamide, N-methyl-N-vinylformamide, N-methyl-N-vinylacetamide, N-methyl-N-vinylpropionamide, N-methyl-N-vinylbutyramide, N-methyl-N-vinylisobutyramide, N-methyl-N-vinyl-2-ethylhexanamide, N-methyl-N-vinyldecanamide, N-methyl-N-vinyldodecanamide, N-methyl-N-vinylstearamide, N-ethyl-N-vinylformamide, N-ethyl-N-vinylacetamide, N-ethyl-N-vinylpropionamide, N-ethyl-N-vinylbutyramide, N-ethyl-N-vinylisobutyramide, N-ethyl-N-vinyl-2-ethylhexanamide, N-ethyl-N-vinyldecanamide, N-ethyl-N-vinyldodecanamide, N-ethyl-N-vinylstearamide, N-isopropyl-N-vinylformamide, N-isopropyl-N-vinylacetamide, N-isopropyl-N-vinylpropionamide, N-isopropyl-N-vinylbutyramide, N-isopropyl-N-vinylisobutyramide, N-isopropyl-N-vinyl-2-ethylhexanamide, N-isopropyl-N-vinyldecanamide, N-isopropyl-N-vinyldodecanamide, N-isopropyl-N-vinylstearamide, N-n-butyl-N-vinylformamide, N-n-butyl-N-vinylacetamide, N-n-butyl-N-vinylpropionamide, N-n-butyl-N-vinylbutyramide, N-n-butyl-N-vinylisobutyramide, N-n-butyl-N-vinyl-2-ethylhexanamide, N-n-butyl-N-vinyldecanamide, N-n-butyl-N-vinyldodecanamide, N-n-butyl-N-vinylstearamide, N-vinylpyrrolidone, N-vinyl-2-piperidone and N-vinylcaprolactam.
  • [0059]
    Particularly preferred polymers for use as anti-agglomeration substance in the present invention include polymers which comprise monomer units of one or more unsubstituted or substituted N-vinyllactams, preferably those having from about 4 to about 8 ring members such as, e.g., N-vinylcaprolactam, N-vinyl-2-piperidone and N-vinylpyrrolidone. These polymers include homo- and copolymers. In the case of copolymers (including, for example, random, block and graft copolymers), the N-vinyllactam (e.g., N-vinylpyrrolidone) units are preferably present in an amount of at least about 10 mole-%, e.g., at least about 30 mole-%, at least about 50 mole-%, at least about 70 mole-%, at least about 80 mole-%, or at least about 90 mole-%. By way of non-limiting example, the comonomers may comprise one or more of those mentioned in the preceding paragraphs, including monomers without functional group (e.g., ethylene, propylene, styrene, etc.), halogenated monomers, etc.
  • [0060]
    If the vinyllactam (e.g., vinylpyrrolidone) monomers (or at least a part thereof) carry one or more substituents on the heterocyclic ring, non-limiting examples of such substituents include alkyl groups (for example, alkyl groups having from 1 to about 12 carbon atoms, e.g., from 1 to about 6 carbon atoms such as, e.g., methyl, ethyl, propyl and butyl), alkoxy groups (for example, alkoxy groups having from 1 to about 12 carbon atoms, e.g., from 1 to about 6 carbon atoms such as, e.g., methoxy, ethoxy, propoxy and butoxy), halogen atoms (e.g., F, Cl and Br), hydroxy, carboxy and amino groups (e.g., dialkylamino groups such as dimethylamino and diethylamino) and any combinations of these substituents.
  • [0061]
    Non-limiting specific examples of vinyllactam polymers for use in the present invention include homo- and copolymers of vinylpyrrolidone which are commercially available from, e.g., International Specialty Products (www.ispcorp.com). In particular, these polymers include
      • (a) vinylpyrrolidone homopolymers such as, e.g., grades K-15 and K-30 with K-value ranges of from 13-19 and 26-35, respectively, corresponding to average molecular weights (determined by GPC/MALLS) of about 10,000 and about 67,000;
      • (b) alkylated polyvinylpyrrolidones such as, e.g., those commercially available under the trade mark GANEX® which are vinylpyrrolidone-alpha-olefin copolymers that contain most of the alpha-olefin (e.g., about 80% and more) grafted onto the pyrrolidone ring, mainly in the 3-position thereof; the alpha-olefins may comprise those having from about 4 to about 30 carbon atoms; the alpha-olefin content of these copolymers may, for example, be from about 10% to about 80% by weight;
      • (c) vinylpyrrolidone-vinylacetate copolymers such as, e.g., random copolymers produced by a free-radical polymerization of the monomers in a molar ratio of from about 70/30 to about 30/70 and having weight average molecular weights of from about 14,000 to about 58,000;
      • (d) vinylpyrrolidone-dimethylaminoethylmethacrylate copolymers;
      • (e) vinylpyrrolidone-methacrylamidopropyl trimethylammonium chloride copolymers such as, e.g., those commercially available under the trade mark GAFQUAT®;
      • (f) vinylpyrrolidone-vinylcaprolactam-dimethylaminoethylmethacrylate terpolymers such as, e.g., those commercially available under the trade mark GAFFIX®;
      • (g) vinylpyrrolidone-styrene copolymers such as, e.g., those commercially available under the trade mark POLECTRON®; a specific example thereof is a graft emulsion copolymer of about 70% vinylpyrrolidone and about 30% styrene polymerized in the presence of an anionic surfactant;
      • (h) vinylpyrrolidone-acrylic acid copolymers such as, e.g., those commercially available under the trade mark ACRYLIDONE® which are produced in the molecular weight range of from about 80,000 to about 250,000.
  • [0070]
    The weight ratio of metal in the metal nanoparticles and anti-agglomeration substance(s) carried thereon can vary over a wide range. The most advantageous ratio depends, inter alia, on factors such as the nature of the anti-agglomeration substance (polymer, low molecular weight substance, etc.) and the size of the metal cores of the nanoparticles (the smaller the size the higher the total surface area thereof and the higher the amount of anti-agglomeration substance that will desirably be present). Usually, the weight ratio will be not higher than about 100:1, e.g., not higher than about 50:1, or not higher than about 30:1. On the other hand, the weight ratio will usually be not lower than about 5:1, e.g., not lower than about 10:1, not lower than about 15:1, or not lower than about 20:1.
  • [0071]
    Metal nanoparticles suitable for use in the present invention can be produced by a number of methods. A non-limiting example of such a method, commonly known as the polyol process, is disclosed in U.S. Pat. No. 4,539,041. A modification of this method is described in, e.g., P.-Y. Silvert et al., “Preparation of colloidal silver dispersions by the polyol process” Part 1—Synthesis and characterization, J. Mater. Chem., 1996, 6(4), 573-577; Part 2—Mechanism of particle formation, J. Mater. Chem., 1997, 7(2), 293-299. The entire disclosures of these documents are expressly incorporated by reference herein. Briefly, in the polyol process a metal compound is dissolved in, and reduced by a polyol such as, e.g., a glycol at elevated temperature to afford corresponding metal particles. In the modified polyol process the reduction is carried out in the presence of a dissolved polymer, i.e., polyvinylpyrrolidone.
  • [0072]
    A particularly preferred modification of the polyol process for producing metal nanoparticles which carry an anti-agglomeration substance such as polyvinylpyrrolidone thereon is described in U.S. Provisional Application Serial Nos. 60/643,378 and 60/643,629 entitled “Production of Metal Nanoparticles,” and “Separation of Metal Nanoparticles,” respectively, the entire disclosures of which are expressly incorporated by reference herein. In a preferred aspect of this modified process, a dissolved metal compound (e.g., a silver compound such as silver nitrate) is combined with and reduced by a polyol (e.g., ethylene glycol, propylene glycol and the like) at an elevated temperature (e.g., at about 120° C.) and in the presence of a heteroatom containing polymer (e.g., polyvinylpyrrolidone) which serves as anti-agglomeration substance.
  • [0073]
    According to a preferred aspect of the present invention, the metal nanoparticles exhibit a narrow particle size distribution. A narrow particle size distribution is particularly advantageous for direct-write applications because it results in a reduced clogging of the orifice of a direct-write device by large particles and provides the ability to form features having a fine line width, high resolution and high packing density.
  • [0074]
    The metal nanoparticles for use in the present invention preferably also show a high degree of uniformity in shape. Preferably, the metal nanoparticles for use in the compositions of the present invention are substantially spherical in shape. Spherical particles are particularly advantageous because they are able to disperse more readily in a liquid suspension and impart advantageous flow characteristics to the metal nanoparticle composition, particularly for deposition using an ink-jet device or similar tool. For a given level of solids loading, a low viscosity metal nanoparticle composition having spherical particles will have a lower viscosity than a composition having non-spherical particles, such as flakes. Spherical particles are also less abrasive than jagged or plate-like particles, reducing the amount of abrasion and wear on the deposition tool.
  • [0075]
    In a preferred aspect of the present invention, at least about 90%, e.g., at least about 95%, or at least about 99% of the metal nanoparticles comprised in the present compositions are substantially spherical in shape. In another preferred aspect, the metal nanoparticle compositions are substantially free of particles in the form of flakes.
  • [0076]
    In yet another preferred aspect, the particles are substantially free of micron-size particles, i.e., particles having a size of about 1 micron or above. Even more preferably, the nanoparticles may be substantially free of particles having a size (=largest dimension, e.g., diameter in the case of substantially spherical particles) of more than about 500 nm, e.g., of more than about 200 nm, or of more than about 100 nm. In this regard, it is to be understood that whenever the size and/or dimensions of the metal nanoparticles are referred to herein and in the appended claims, this size and these dimensions refer to the nanoparticles without anti-agglomeration substance thereon, i.e., the metal cores of the nanoparticles. Depending on the type and amount of anti-agglomeration substance, an entire nanoparticle, i.e., a nanoparticle which has the anti-agglomeration substance thereon, may be significantly larger than the metal core thereof. Also, the term “nanoparticle” as used herein and in the appended claims encompasses particles having a size/largest dimension of the metal cores thereof of up to about 900 nm, preferably of up to about 500 nm, more preferably up to about 200 nm, or up to about 100 nm.
  • [0077]
    By way of non-limiting example, not more than about 5%, e.g., not more than about 2%, not more than about 1%, or not more than about 0.5% of the metal nanoparticles may be particles whose largest dimension (and/or diameter) is larger than about 200 nm, e.g., larger than about 150 nm, or larger than about 100 nm. In a particularly preferred aspect, at least about 90%, e.g., at least about 95%, of the metal nanoparticles will have a size of not larger than about 80 nm and/or at least about 80% of the metal nanoparticles will have a size of from about 20 nm to about 70 nm. For example, at least about 90%, e.g., at least about 95% of the nanoparticles may have a size of from about 30 nm to about 50 nm.
  • [0078]
    In another aspect, the metal nanoparticles may have an average particle size (number average) of at least about 10 nm, e.g., at least about 20 nm, or at least about 30 nm, but preferably not higher than about 80 nm, e.g., not higher than about 70 nm, not higher than about 60 nm, or not higher than about 50 nm. For example, the metal nanoparticles may have an average particle size in the range of from about 25 nm to about 75 nm.
  • [0079]
    In yet another aspect of the present invention, at least about 80 volume percent, e.g., at least about 90 volume percent of the metal nanoparticles may be not larger than about 2 times, e.g., not larger than about 1.5 times the average particle size (volume average).
  • [0080]
    As indicated above, nanoparticles may form agglomerates as a result of their relatively high surface energies, as compared to larger particles. Even in the presence of the anti-agglomeration substance the compositions of the present invention may contain a minor amount of agglomerates in the form of soft agglomerates, particularly after storage for extended periods of time. However it is known that such soft agglomerates may be dispersed easily by treatments such as exposure to ultrasound in a liquid medium, sieving, high shear mixing and 3-roll milling.
  • [0081]
    The average particle sizes and particle size distributions described herein may be measured by mixing samples of the powders in a liquid medium and exposing the resultant suspension to ultrasound through either an ultrasonic bath or horn. The ultrasonic treatment supplies sufficient energy to disperse the soft agglomerates into primary particles. The primary particle size and size distribution may then be measured by, e.g., SEM or TEM. Thus, the references to particle size herein refer to the primary particle size, such as after lightly dispersing soft agglomerates of the particles.
  • [0082]
    The nanoparticles that are useful in metal nanoparticle compositions according to the present invention preferably have a high degree of purity. For example, the particles (without anti-agglomeration substance) may include not more than about 1 atomic percent impurities, e.g., not more than about 0.1 atomic percent impurities, preferably not more than about 0.01 atomic percent impurities. Impurities are those materials that are not intended in the final product (e.g., the conductive feature) and that adversely affect the properties of the final product. For many electronic applications, the most critical impurities to avoid are Na, K, Cl, S and F.
  • [0083]
    The metal nanoparticles carrying an anti-agglomeration substance thereon for use in to the present invention may, of course, also be produced by processes which are different from the (modified) polyol process referred to above. By way of non-limiting example, particles coated with an anti-agglomeration substance may be produced by a spray pyrolysis process. One or more coating precursors can vaporize and fuse to the hot nanoparticle surface and thermally react resulting in the formation of a thin film coating by chemical vapor deposition (CVD). Preferred coatings deposited by CVD include metal oxides. Further, the coating can be formed by physical vapor deposition (PVD) wherein a coating material physically deposits on the surface of the particles. Preferred coatings deposited by PVD include organic materials. Alternatively, a gaseous coating precursor can react in the gas phase forming small particles, for example, less than about 5 nanometers in size, which then diffuse to the larger metal nanoparticle surface and sinter onto the surface, thus forming a coating. This method is referred to as gas-to-particle conversion (GPC). Another possible surface coating method is surface conversion of the particles by reaction with a vapor phase reactant to convert the surface of the nanoparticles to a different material than that originally contained in the particles.
  • [0084]
    In another aspect, the metal nanoparticles can be coated with an intrinsically conductive polymer (which at the same time may serve as an anti-agglomeration substance), preventing agglomeration in the composition and providing a conductive patch after solidification of the composition.
  • [0085]
    Vehicle
  • [0086]
    The vehicle for use in the compositions of the present invention is preferably a liquid which is capable of stably dispersing the metal nanoparticles carrying the anti-agglomeration substance thereon, e.g., are capable of affording a dispersion that can be kept at room temperature for several days or even one, two, three weeks or months or even longer without substantial agglomeration and/or settling of the metal nanoparticles. To this end, it is preferred for the vehicle and/or individual components thereof to be compatible with the surface of the nanoparticles, e.g., to be capable of interacting (e.g., electronically and/or sterically and/or by hydrogen bonding and/or dipole-dipole interaction, etc.) with the surface of the nanoparticles and in particular, with the anti-agglomeration substance.
  • [0087]
    It is particularly preferred for the vehicle to be capable of dissolving the anti-agglomeration substance to at least some extent, for example, in an amount (at 20° C.) of at least about 5 g of anti-agglomeration substance per liter of vehicle, particularly in an amount of at least about 10 g of anti-agglomeration substance, e.g., at least about 15 g, or at least about 20 g per liter of vehicle, preferably in an amount of at least about 100 g, or at least about 200 g per liter of vehicle. In this regard, it is to be appreciated that these preferred solubility values are merely a measure of the compatibility between the vehicle and the anti-agglomeration substance. They are not to be construed as indication that in the compositions of the present invention the vehicle is intended to actually dissolve the anti-agglomeration substance and remove it from the surface of the nanoparticles. On the contrary, the vehicle will usually not remove the anti-agglomeration substance from the surface of the nanoparticles to more than a minor extent, if at all.
  • [0088]
    In view of the preferred interaction between the vehicle and/or individual components thereof and the anti-agglomeration substance on the surface of the nanoparticles, the most advantageous vehicle and/or component thereof for a composition according to the present invention is largely a function of the nature of the anti-agglomeration substance. For example, an anti-agglomeration substance which comprises one or more polar groups such as, e.g., a polymer like polyvinylpyrrolidone will advantageously be combined with a vehicle which comprises (or predominantly consists of) one or more polar components (solvents) such as, e.g., a protic solvent, whereas an anti-agglomeration substance which substantially lacks polar groups will preferably be combined with a vehicle which comprises, at least predominantly, aprotic, non-polar components.
  • [0089]
    Particularly if the compositions of the present invention are intended for use in direct-write applications such as, e.g., ink-jet printing, the vehicle is preferably selected to also satisfy the requirements imposed by the direct-write method and tool such as, e.g., an ink-jet head, particularly in terms of viscosity and surface tension of the composition. These requirements are discussed in more detail further below. Another consideration in this regard is the compatibility of the nanoparticle composition with the substrate in terms of, e.g., wetting behavior (contact angle with the substrate).
  • [0090]
    In a preferred aspect, the vehicle of a composition according to the present invention may comprise a mixture of at least two solvents, preferably at least two organic solvents, e.g., a mixture of at least three organic solvents, or at least four organic solvents. The use of more than one solvent is preferred because it allows, inter alia, to adjust various properties of a composition simultaneously (e.g., viscosity, surface tension, contact angle with intended substrate etc.) and to bring all of these properties as close to the optimum values as possible.
  • [0091]
    The solvents comprised in the vehicle may be polar or non-polar or a mixture of both, mainly depending on the nature of the anti-agglomeration substance. The solvents should preferably be miscible with each other to a significant extent. Non-limiting examples of solvents that are useful for the purposes of the present invention include alcohols, polyols, amines, amides, esters, acids, ketones, ethers, water, saturated hydrocarbons, and unsaturated hydrocarbons.
  • [0092]
    Particularly in the case of an anti-agglomeration substance which comprises one or more heteroatoms which are available for hydrogen bonding, ionic interactions, etc. (such as, e.g., O and N), it is advantageous for the vehicle of a composition according to the present invention to comprise one or more polar solvents and, in particular, protic solvents. For example, the vehicle may comprise a mixture of at least two protic solvents, or at least three protic solvents. Non-limiting examples of such protic solvents include alcohols (e.g., aliphatic and cycloaliphatic alcohols having from 1 to about 12 carbon atoms such as, e.g., methanol, ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, sek.-butanol, tert-butanol, the pentanols, the hexanols, the octanols, the decanols, the dodecanols, cyclopentanol, cyclohexanol, and the like), polyols (e.g., alkanepolyols having from 2 to about 12 carbon atoms and from 2 to about 4 hydroxy groups such as, e.g., ethylene glycol, propylene glycol, butylene glycol, 1,3-propanediol; 1,3-butanediol, 1,4-butanediol, 2-methyl-2,4-pentanediol, glycerol, trimethylolpropane, pentaerythritol, and the like), polyalkylene glycols (e.g., polyalkylene glycols comprising from about 2 to about 5 C2-4 alkylene glycol units such as, e.g., diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene gycol, tripropylene glycol and the like) and partial ethers and esters of polyols and polyalkylene glycols (e.g., mono(C1-6 alkyl) ethers and monoesters of the polyols and polyalkylene glycols with C1-6 alkanecarboxylic acids, such as, e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether and diethylene glycol monobutyl ether (DEGBE), ethylene gycol monoacetate, diethylene glycol monoacetate, and the like).
  • [0093]
    In one aspect of the composition of the present invention, the vehicle may comprise at least two solvents, e.g., at least three solvents, which solvents are preferably selected from C2-4 alkanols, C2-4 alkanediols and glycerol. For example, the vehicle may comprise ethanol, ethylene glycol and glycerol such as, e.g., from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on the total weight of the vehicle. In a preferred aspect, the vehicle may comprise about 40% by weight of ethylene glycol, about 35% by weight of ethanol and about 25% by weight of glycerol.
  • [0094]
    In another aspect of the composition of the present invention, the vehicle may comprise a C1-4 monoalkyl ether of a C2-4 alkanediol and/or of a polyalkylene glycol.
  • [0095]
    In yet another aspect, the vehicle may comprise not more than about 5 weight percent of water, e.g., not more than about 2 weight percent, or not more than about 1 weight percent of water, based on the total weight of the vehicle. For example, the vehicle may be substantially anhydrous.
  • [0096]
    Non-limiting further examples of organic solvents that may advantageously be used as the vehicle or a component thereof, respectively, of the compositions of the present invention include N,N-dimethylformamide, N,N-dimethylacetamide, ethanolamine, diethanolamine, triethanolamine, trihydroxymethylaminomethane, 2-(isopropylamino)-ethanol, 2-pyrrolidone, N-methylpyrrolidone, acetonitrile, the terpineols, ethylene diamine, benzyl alcohol, isodecanol, nitrobenzene and nitrotoluene.
  • [0097]
    As discussed in more detail below, when selecting a solvent combination for the vehicle of the composition of the present invention, it is desirable to also take into account the requirements, if any, imposed by the deposition tool (e.g., in terms of viscosity and surface tension of the composition) and the surface characteristics (e.g., hydrophilic or hydrophobic) of the intended substrate. In the case of preferred compositions of the present invention, particularly those intended for ink-jet printing with a piezo head, the preferred viscosity thereof (measured at 20° C.) is not lower than about 5 cP, e.g., not lower than about 8 cP, or not lower than about 10 cP, and not higher than about 30 cP, e.g., not higher than about 20 cP, or not higher than about 15 cP. Preferably, the viscosity shows only small temperature dependence in the range of from about 20° C. to about 40° C., e.g., a temperature dependence of not more than about 0.4 cP/° C. It has surprisingly been found that in the case of preferred vehicles for use in the present invention the presence of metal nanoparticles does not significantly change the viscosity of the vehicle, at least at relatively low loadings such as, e.g., up to about 20 weight percent. This may in part be due to the usually large difference in density between the vehicle and the nanoparticles which manifests itself in a much lower number of particles than the number of particles that the mere weight percentage thereof would suggest.
  • [0098]
    Further, the above preferred compositions of the present invention exhibit preferred surface tensions (measured at 20° C.) of not lower than about 20 dynes/cm, e.g., not lower than about 25 dynes/cm, or not lower than about 30 dynes/cm, and not higher than about 40 dynes/cm, e.g., not higher than about 35 dynes/cm.
  • [0099]
    In other embodiments, the composition of the present invention comprises water. The composition of the present invention may comprise up to 50% by weight of water. In one embodiment, the composition of the present invention may comprise from about 30% to about 50% by weight water; from about 45% to about 48% by weight water; or from about 30% to about 48% by weight water.
  • [0100]
    Optional Additives
  • [0101]
    Additives may optionally be present in the metal nanoparticle compositions of the present invention. Non-limiting examples of such additives will be discussed below. If the compositions of the present invention are intended for use in the production of conductive materials it should be taken into account that additives will in many cases have an adverse effect on the conductivity of the final material, in particular, if they can be removed from the material only with difficulty (e.g., by decomposition with the application of high temperatures) or not at all. Therefore it will usually be desirable to keep the amount of conductivity-impairing additives at a minimum in these cases. Of course, if the composition of the present invention is intended for a non-electrical use (for example, if the composition is to be used for decorative purposes, graphic applications, mirror applications etc.), the selection of the types and amounts of additives will not be influenced by considerations relating to conductivity.
  • [0102]
    The metal nanoparticle compositions of the present invention may include an adhesion promoter for improving the adhesion of the metal (e.g., conductive feature) to the underlying substrate. It has been found that metal structures made from the compositions according to the present invention show a satisfactory to excellent adhesion to various substrates without the presence of adhesion promoters. For example, in the case of preferred compositions such as those which comprise metal nanoparticles and in particular, silver nanoparticles and polyvinylpyrrolidone as anti-agglomeration substance it has been found that the anti-agglomeration substance itself may act as adhesion promoter, especially in the case of polymeric substrates. Further, the adhesive strength may be dependent, inter alia, on the processing temperature of the deposited composition. Particularly, even in the absence of separately added adhesion promoter the preferred compositions of the present invention have been found to exhibit very good adhesion to FR4 (glass fibers impregnated with epoxy resin) substrates when processed (cured) in the temperature range of from about 100° C. to about 180° C., satisfactory to very good adhesion to Mylar® substrates in the temperature range of from about 100° C. to about 180° C., satisfactory adhesion to Kapton® substrates at temperatures of about 200° C. and higher, and to glass substrates at temperatures of about 350° C. and higher. Good to excellent adhesion to ITO substrates has been observed at temperatures of about 350° C. and higher.
  • [0103]
    Especially in the case of glass surfaces the adhesion of silver nanoparticle compositions according to the present invention can be (significantly) improved by the addition of an adhesion promoter. Non-limiting examples of adhesion promoters for use in the present invention (with silver and other metals which would benefit from the use of an adhesion promoter) include metals as well as metal compounds which are oxides or can be converted to oxides by thermal decomposition, oxidation in an oxygen containing atmosphere, etc. Non-limiting examples of metals for the adhesion promoter include B, Si, Pb, Cu, Zn, Ni and Bi. Especially in the case of a glass substrate, a low melting point glass is yet another example of a suitable adhesion promoter. A specific example of a preferred adhesion promoter is bismuth nitrate (which decomposes to form bismuth oxide at a temperature of about 260° C.). By way of non-limiting example, an atomic ratio Ag:Bi in the range of from about 15:1 to about 7:1 may be particularly advantageous. The addition of bismuth nitrate results in a consistently good adhesion of deposited silver to glass surfaces over the entire tested temperature range of from about 100° C. to about 550° C.
  • [0104]
    In the case of, e.g., nickel, on the other hand, the adhesion to glass substrates is good even without the presence of an adhesion promoter. This may be due to the formation of nickel oxide during the thermal processing of a deposited nickel nanoparticle composition of the present invention.
  • [0105]
    Of course, in addition to bismuth nitrate and the other adhesion promoters mentioned above, there is a variety of other adhesion promoters that can afford desirable results when added to the compositions of the present invention. The effectiveness of a given adhesion promoter will usually depend, inter alia, on the metal of the nanoparticle, the substrate, the processing temperature, etc. The adhesion promoter is preferable soluble in the vehicle of the composition of the present invention but may also be present in the form of, e.g., ultrafine particles that are dispersed in the liquid vehicle. In other words, adhesion promoters can be added to the ink in particulate form (e.g., in the case Ni in the form of nickel nanoparticles). Further non-limiting examples of adhesion promoters for use in the present invention are disclosed in, e.g., U.S. Pat. No. 5,750,194, the entire disclosure whereof is incorporated by reference herein in its entirety. Furthermore, polymers such as, e,g., polyamic acid, acrylics and styrene acrylics can improve the adhesion of a metal to a polymer substrate, as can substances such as coupling agents, titanates and silanes.
  • [0106]
    An adhesion promoter can also be added to the ink in the form of a chemical precursor to a metal such as, e.g., in the form of a metal salt (e.g., a carboxylate or nitrate), a metal alkoxide, etc. Adhesion promoters can also be applied to the substrate prior to printing of a nanoparticle ink, preferably by the same printing method but optionally also by an alternative method such as, e.g., spin coating or dip coating.
  • [0107]
    It also is to be noted that, in certain cases the polymer which serves the function of an anti-agglomeration substance for the nanoparticles of, e.g., an ink, may also provide improved structural integrity on a variety of substrates when curing is performed at relatively low temperatures (e.g., from about 75° C. to about 350° C.). At such low temperatures, the polymer (shell) will not volatilize, but rather rearrange while allowing the metal cores of the particles to touch and sinter together. The polymer now can serve the function of adhesion promoter between the Ag particles and the substrate. In addition, it may also provide additional cohesive strength between individual particles.
  • [0108]
    The metal nanoparticle compositions of the present invention can also include rheology modifiers. Non-limiting examples of rheology modifiers that are suitable for use in the present invention include SOLTHIX 250 (Avecia Limited), SOLSPERSE 21000 (Avecia Limited), styrene allyl alcohol (SAA), ethyl cellulose, carboxy methylcellulose, nitrocellulose, polyalkylene carbonates, ethyl nitrocellulose, and the like. These additives can reduce spreading of a metal nanoparticle composition after deposition, as discussed in more detail below.
  • [0109]
    The metal nanoparticle compositions of the present invention may include further additives such as, e.g., wetting angle modifiers, humectants, crystallization inhibitors and the like. Of particular interest are often crystallization inhibitors as they prevent crystallization and the associated increase in surface roughness and film uniformity during curing at elevated temperatures and/or over extended periods of time. However, it is preferred for the nanoparticle compositions of the present invention to be substantially free of metal precursor compounds such as those disclosed in, e.g., published U.S. Patent Application Nos. 2003/0148024 A1and 2003/0180451 A1, the entire disclosures whereof are expressly incorporated by reference herein. Also, compositions in accordance with the present invention preferably do not comprise added binder, e.g., polymeric binder. In this regard it is to be noted that, in the case of polymeric anti-agglomeration substances such as, e.g., polyvinylpyrrolidone, the anti-agglomeration substance itself may serve as a binder, as explained in more detail below.
  • [0110]
    It is preferred for the total loading of metal nanoparticles in the compositions of the present invention to be not higher than about 75% by weight, such as from about 5% by weight to about 60% by weight, based on the total weight of the composition. Loadings in excess of the preferred amounts can lead to undesirably high viscosities and/or undesirable flow characteristics. Of course, the maximum loading which still affords useful results also depends on the density of the metal. In other words, the higher the density of the metal of the nanoparticles, the higher will be the acceptable and desirable loading in weight percent. In preferred aspects of the compositions of the present invention, the nanoparticle loading is at least about 10% by weight, e.g., at least about 15% by weight, at least about 20% by weight, or at least about 40% by weight. Depending on the metal, the loading will often not be higher than about 65% by weight, e.g. not higher than about 60% by weight. These percentages refer to the total weight of the nanoparticles, i.e., including any anti-agglomeration substance carried (e.g., adsorbed) thereon.
  • [0111]
    The metal nanoparticle compositions of the present invention can also include plasticizing agents. Without being bound by any particular theory, it is possible that plasticizing agents cause the anti-agglomeration substance on the surface of the metal nanoparticles to at least partially expose the metal nanoparticle core. In one embodiment, the exposing occurs at room temperature. Examples of plasticizing agents that may be used in the present invention include, but are not limited to water, phthalic esters (e.g., di-2-ethylhexyl phthalate, di-n-octyl phthalate, di-i-octyl phthalate, di-i-decyl phthalate, di-n-undecyl phthalate, and di-n-tridecyl phthalate), aromatic alkyl tricarboxylates (e.g., tri-2-ethylhexyl trimellitate), phosphate esters, aliphatic acid esters (e.g., dialkyl adipates like bis(1-butylpentyl) adipate and di-2-ethyhexyl adipate), sebacates (e.g., di-2-ethyhexyl sebacate), azelates (e.g., di-2-ethyhexyl azelate), benzoates, butylates, epoxy aliphatic acid esters, glycolic acid esters, propionic acid esters, sulfonates, carboxylates, succinic acid esters, maleates, fumaric acid esters, phthalic acid esters, stearic acid esters, amines (e.g., butylamine), sugars (e.g., glucose and xylose), amino acids (e.g., lysine), aldehydes (e.g., hexanal), carbonates (e.g., ethylene carbonate), amides, ethers, alcohols (e.g., ethanol, ethylene glycol, polyethylene glycol, and glycerol), lactones, and expoxidized oils (e.g., epoxidized linseed oil and epoxidized soya oil).
  • [0112]
    The metal nanoparticle compositions of the present invention can also include surfactants. Without being bound by any particular theory, it is possible that surfactants also cause the anti-agglomeration substance on the surface of the metal nanoparticles to at least partially expose the metal nanoparticle core. Examples of surfactants that may be used in the present invention include, but are not limited to fatty acid esters, fatty amines, glycerol, and glycerol esters.
  • [0113]
    Substrates
  • [0114]
    Preferred metal nanoparticle compositions according to the present invention can be deposited and converted to a conductive feature at low temperatures, thereby enabling the use of a variety of substrates having a relatively low softening (melting) or decomposition temperature.
  • [0115]
    Non-limiting examples of substrates that are particularly advantageous according to the present invention include substrates comprising one or more of fluorinated polymer, polyimide, epoxy resin (including glass-filled epoxy resin), polycarbonate, polyester, polyethylene, polypropylene, polyvinyl chloride, ABS copolymer, synthetic paper, flexible fiberboard, non-woven polymeric fabric, cloth and other textiles. Other particularly advantageous substrates include cellulose-based materials such as wood or paper, and metallic foil and glass (e.g., thin glass). The substrate may be coated. Although the compositions of the present invention can be used particularly advantageously for temperature-sensitive substrates, it is to be appreciated that other substrates such as, e.g., metallic and ceramic substrates can also be used in accordance with the present invention.
  • [0116]
    Of particular interest for display applications are glass substrates and ITO coated glass substrates. Other glass coatings that the metal features may be printed on in flat panel display applications include semiconductors such as c—Si on glass, amorphous Si on glass, poly-Si on glass, and organic conductors and semiconductors printed on glass. The glass may also be substituted with, e.g., a flexible organic transparent substrate such as PET or PEN. The metal (e.g., Ag) may also be printed on top of a black layer or coated with a black layer to improve the contrast of a display device. Other substrates of particular interest include printed circuit board substrates such as FR4, textiles including woven and non-woven textiles.
  • [0117]
    Another substrate of particular interest is natural or synthetic paper, in particular, paper that has been coated with specific layers to enhance gloss and accelerate the infiltration of ink solvent or ink vehicle. A preferred example of a glossy coating for ink-jet paper includes alumina nanoparticles such as fumed alumina in a binder. Also, an Ag ink according to the present invention that is ink-jet printed on EPSON glossy photo paper and heated for about 30 min at about 100° C. is capable of exhibiting highly conductive Ag metal lines with a bulk conductivity in the 10 micro-Ω cm range.
  • [0118]
    According to a preferred aspect of the present invention, the substrate onto which the metal nanoparticle composition is deposited may have a softening and/or decomposition temperature of not higher than about 225° C., e.g., not higher than about 200° C., not higher than about 185° C., not higher than about 150° C., or not higher than about 125° C.
  • [0119]
    Deposition of Fine Features
  • [0120]
    A difficulty that may be encountered in the printing and processing of low viscosity metal nanoparticle compositions is that the composition can wet the surface and rapidly spread to increase the width of the deposit, thereby negating the advantages of fine line printing. This is particularly true when ink-jet printing is employed to deposit fine features such as interconnects, because ink-jet technology puts relatively strict upper boundaries on the viscosity of the composition that can be employed. Nonetheless, ink-jet printing is a preferred low-cost, large-area deposition technology that can be used to deposit the metal nanoparticle compositions of the present invention. It has surprisingly been found that the preferred compositions of the present invention and in particular, compositions comprising silver nanoparticles carrying thereon polyvinylpyrrolidone as anti-agglomeration substance in a vehicle which comprises a mixture of protic solvents such as, e.g., a mixture of ethylene glycol, ethanol and glycerol, can be deposited on a variety of substrates without any significant spreading, thereby enabling the production of very fine conductive features.
  • [0121]
    According to a preferred aspect of the present invention, the metal nanoparticle compositions can be confined on the substrate, thereby enabling the formation of features having a small minimum feature size, the minimum feature size being the smallest dimension in the x-y axis, such as the width of a conductive line. The preferred metal nanoparticle compositions of the present invention can be confined to regions having a width of not greater than about 200 μm, preferably not greater than about 150 μm, e.g., not greater than about 100 μm, or not greater than about 50 μm, even without the use of any anti-spreading additives and/or without resorting to any measures such as those discussed below.
  • [0122]
    In some cases it may, however, be advantageous to add small amounts of rheology modifiers such as styrene allyl alcohol (SAA) and other polymers to the metal nanoparticle composition to reduce spreading. Spreading can also be controlled by rapidly drying the compositions during printing by irradiating the composition during deposition.
  • [0123]
    Spreading can also be controlled by the addition of a low decomposition temperature polymer in monomer form. The monomer can be polymerized during deposition by thermal or radiation (e.g., ultraviolet) means, providing a network structure to maintain line shape. The resultant polymer can then be either retained or removed during subsequent processing of the conductor.
  • [0124]
    Another method comprises patterning an otherwise non-wetting substrate with wetting enhancement agents that control the spreading and also yield increased adhesion. By way of non-limiting example, this may be achieved by functionalizing the substrate surface with functional groups such as, e.g., hydroxide or carboxylate groups.
  • [0125]
    The fabrication of features with feature widths of not greater than about 100 μm or features with a minimum feature size of not greater than about 100 μm from a low viscosity composition may require the confinement of the metal nanoparticle composition so that the composition does not spread over certain defined boundaries. Various methods can be used to confine the composition on a surface, including surface energy patterning by increasing or decreasing the hydrophobicity (surface energy) of the surface in selected regions corresponding to where it is desired to confine the metal nanoparticles or eliminate the metal nanoparticles. These methods can be classified as physical barrier, electrostatic barrier, magnetic barrier, surface energy difference, and process related methods such as increasing the metal nanoparticle viscosity to reduce spreading, for example by freezing or drying the composition very rapidly once it strikes the surface.
  • [0126]
    In physical barrier approaches, a confining structure is formed that keeps the metal nanoparticle composition from spreading. These confining structures may be trenches and cavities of various shapes and depths below a flat or curved surface which confine the flow of the metal nanoparticle composition. Such trenches can be formed by chemical etching or by photochemical means. The physical structure confining the metal nanoparticle composition can also be formed by mechanical means including embossing a pattern into a softened surface or means of mechanical milling, grinding or scratching features. Trenches can also be formed thermally, for example by locally melting a low melting point coating such as a wax coating. Alternatively, retaining barriers and patches can be deposited to confine the flow of a composition within a certain region. For example, a photoresist layer can be spin coated on a polymer substrate. Photolithography can be used to form trenches and other patterns in the photoresist layer. These patterns can be used to retain metal nanoparticle composition that is deposited onto these preformed patterns. After drying, the photolithographic mask may or may not be removed with the appropriate solvents without removing the deposited metal. Retaining barriers can also be deposited with direct-write deposition approaches such as ink-jet printing or any other direct-write approach, as disclosed herein.
  • [0127]
    For example, a polymer trench can be ink-jet printed onto a flat substrate by depositing two parallel lines with narrow parallel spacing. A metal nanoparticle composition of the present invention can be printed between the two polymer lines to confine the composition. Another group of physical barriers include printed lines or features with a certain level of porosity that can retain a low viscosity composition by capillary forces. The confinement layer may comprise particles applied by any of the techniques disclosed herein. The particles confine the metal nanoparticle composition that is deposited onto the particles to the spaces between the particles because of wetting of the particles by the metal nanoparticle composition.
  • [0128]
    Surface energy patterning can be classified by how the patterning is formed, namely by mechanical, thermal, chemical or photochemical means. In mechanical methods, the physical structure confining the metal nanoparticle composition is formed by mechanical means including embossing a pattern into a softened surface, milling features, or building up features to confine the composition. In thermal methods, heating of the substrate is used to change the surface energy of the surface, either across the entire surface or in selected locations, such as by using a laser or thermal print head. In chemical methods, the entire surface or portions of the surface are chemically modified by reaction with some other species. In one aspect, the chemical reaction is driven by local laser heating with either a continuous wave or pulsed laser. In photochemical methods, light from either a conventional source or from a laser is used to drive photochemical reactions that result in changes in surface energy.
  • [0129]
    The methods of confining metal nanoparticle compositions disclosed herein can involve two steps in series—first the formation of a confining pattern, that may be a physical or chemical confinement method, and second, the application of a metal nanoparticle composition to the desired confinement areas.
  • [0130]
    Offset printing or lithographic printing can be used to print high resolution patterns that correspond to at least two levels of surface energies. In one aspect, the printing is carried out on a hydrophobic surface and a hydrophilic material is printed. The regions where no printing occurs correspond to hydrophobic material. A hydrophobic metal nanoparticle composition can then be printed onto the hydrophobic regions thereby confining the composition. Alternatively, a hydrophilic nanoparticle composition can be printed onto the hydrophilic electrostatically printed regions. The width of the hydrophobic and hydrophilic regions may be not greater than about 100 μm, e.g., not greater than about 75 μm, not greater than about 50 μm, or not greater than about 25 μm.
  • [0131]
    The metal nanoparticle composition confinement may be accomplished by applying a photoresist and then laser patterning the photoresist and removing portions of the photoresist. The confinement may be accomplished by a polymeric resist that has been applied by another jetting technique or by any other technique resulting in a patterned polymer. In one aspect, the polymeric resist is hydrophobic and the substrate surface is hydrophilic. In that case, the metal nanoparticle composition utilized is hydrophilic resulting in confinement of the composition in the portions of the substrate that are not covered by the polymeric resist.
  • [0132]
    A laser can be used in various ways to modify the surface energy of a substrate in a patterned manner. The laser can be used, for example, to remove hydroxyl groups through local heating. These regions are converted to more hydrophobic regions that can be used to confine a hydrophobic or hydrophilic metal nanoparticle composition. The laser may also be used to remove selectively a previously applied surface layer formed by chemical reaction of the surface with a silanating agent.
  • [0133]
    In one aspect, a surface is laser processed to increase the hydrophilicity in regions where the laser strikes the surface. A polyimide substrate is coated with a thin layer of hydrophobic material, such as a fluorinated polymer. A laser, such as a pulsed yttrium aluminum garnet (YAG), excimer or other ultraviolet (UV) or shorter wavelength pulsed laser, can be used to remove the hydrophobic surface layer exposing the hydrophilic layer underneath. Translating (e.g., on an x-y axis) the laser allows patterns of hydrophilic material to be formed. Subsequent application of a hydrophilic metal nanoparticle composition to the hydrophilic regions allows confinement of the composition. Alternatively, a hydrophobic metal nanoparticle composition can be used and applied to the hydrophobic regions resulting in composition confinement.
  • [0134]
    In another aspect, a surface is laser processed to increase the hydrophobicity in regions where the laser strikes the surface. A hydrophobic substrate such as a fluorinated polymer can be chemically modified to form a hydrophilic layer on its surface. Suitable modifying chemicals include solutions of sodium naphthalenide. Suitable substrates include polytetrafluoroethylene and other fluorinated polymers. The dark hydrophilic material formed by exposing the polymer to the solution can be removed in selected regions by using a laser. Continuous wave and pulsed lasers can be used. Hydrophilic metal nanoparticle compositions, for example aqueous based compositions, can be applied to the remaining dark material. Alternatively, hydrophobic metal nanoparticle compositions, such as those based on solutions in non-polar solvents, can be applied to the regions where the dark material was removed leaving the hydrophobic material underneath. Ceramic surfaces can be hydroxylated by heating in moist air or otherwise exposing the surface to moisture. The hydroxylated surfaces can be silanated to create a monolayer of hydrophobic molecules. The laser can be used to selectively remove the hydrophobic surface layer exposing the hydrophilic material underneath. A hydrophobic patterned layer can be formed directly by micro-contact printing using a stamp to apply a material that reacts with the surface to leave exposed a hydrophobic material such as, e.g., an aliphatic hydrocarbon chain. The metal nanoparticle composition can be applied directly to the hydrophilic regions or hydrophobic regions using a hydrophilic or hydrophobic metal nanoparticle composition, respectively.
  • [0135]
    A surface with patterned regions of hydrophobic and hydrophilic regions can be formed by micro-contact printing. In this approach, a stamp is used to apply a reagent to selected regions of a surface. This reagent can form a self-assembled monolayer that provides a hydrophobic surface. The regions between the hydrophobic surface regions can be used to confine a hydrophilic metal nanoparticle composition.
  • [0136]
    Metal nanoparticle composition modification can also be employed to confine the composition on the substrate. Such methods restrict spreading of the compositions by methods other than substrate modification. A metal nanoparticle composition including a binder can be used for surface confinement. By way of non-limiting example, the binder can be chosen such that it is a solid at room temperature, but is a liquid suitable for ink-jet deposition at higher temperatures. These compositions are suitable for deposition through, for example, a heated ink-jet head.
  • [0137]
    Binders can also be used in the metal nanoparticle compositions of the present invention to provide mechanical cohesion and limit spreading of the composition after deposition, especially in non-electric and non-electronic applications. By way of non-limiting example, the binder may be a solid at room temperature. During ink-jet printing, the binder is heated and becomes flowable. In one aspect, the binder is a solid at room temperature, when heated to greater than about 50° C. the binder melts and flows allowing for ease of transfer and good wetting of the substrate, then upon cooling to room temperature the binder becomes solid again maintaining the shape of the deposited pattern. The binder can also react in some instances. Preferred binders include waxes, polymers such as, e.g., styrene allyl alcohols, polyalkylene carbonates and polyvinyl acetals, cellulose based materials, tetradecanol, trimethylolpropane and tetramethylbenzene. The preferred binders have good solubility in the vehicle used in the metal nanoparticle composition and should be processable in the melt form. For example, styrene allyl alcohol is soluble in dimethylacetamide, solid at room temperature and becomes fluid-like upon heating to about 80° C.
  • [0138]
    The binder in many cases should depart out of the ink-jet printed feature or decompose cleanly during thermal processing, leaving little or no residuals after processing the metal nanoparticle composition. The departure or decomposition can include vaporization, sublimation, unzipping, partial polymer chain breaking, combustion, or other chemical reactions induced by a reactant present on the substrate material, or deposited on top of the material.
  • [0139]
    In a preferred aspect of the present invention, the anti-agglomeration substance will also serve the function of a binder. A non-limiting example of such an anti-agglomeration substance/binder is a polymer such as polyvinylpyrrolidone. For example, upon heating the deposited nanoparticle composition, the polymer may become mobile and form a polymeric matrix or the like in which the metal nanoparticles are embedded.
  • [0140]
    Other methods for controlling the spreading during printing of a low viscosity metal nanoparticle composition according to the present invention include depositing a composition onto a cooled substrate, freezing the composition as the droplets contact the substrate, removing at least the solvent without melting the composition, and converting the remaining components of the composition to the desired structure or material. The melting point of the composition is preferably less than about 25° C. Preferred solvents include higher molecular weight alcohols. It is preferred to cool the substrate to less than about 10° C.
  • [0141]
    Yet another method for controlling the spreading during printing according to the present invention comprises the steps of depositing a metal nanoparticle composition onto a porous substrate, thereby limiting the spreading of the composition, and converting the composition to a desired structure, e.g., a conductive feature. In one aspect, the porosity in the substrate is created by laser patterning. The porosity can be limited to the very surface of the substrate.
  • [0142]
    Yet another method for controlling the spreading of a low viscosity metal nanoparticle composition according to the present invention includes the steps of patterning the substrate to form regions with two distinct levels of porosity where the porous regions form the pattern of a desired structure. The metal nanoparticle composition can then be deposited, such as by ink-jet printing, onto the regions defining the pattern thereby confining the metal nanoparticle composition to these regions, and converting the deposited metal nanoparticle composition to a desired structure, e.g., a conductive feature. Preferred substrates are polyimide, and epoxy laminates. In one aspect the patterning may be carried out with a laser. In another aspect the patterning may be carried out using photolithography. In another aspect, capillary forces pull at least some portion of the composition into the porous substrate.
  • [0143]
    Spreading of the metal nanoparticle composition is influenced by a number of factors. A drop of liquid placed onto a surface will either spread or not depending on the surface tension of the liquid, the surface tension of the solid and the interfacial tension between the solid and the liquid. If the contact angle is greater than 90 degrees, the liquid is considered non-wetting and the liquid tends to bead or shrink away from the surface. For contact angles less than 90 degrees, the liquid can spread on the surface. For the liquid to completely wet, the contact angle must be zero. For spreading to occur, the surface tension of the liquid must be lower than the surface tension of the solid on which it resides.
  • [0144]
    In one aspect of the present invention, a metal nanoparticle composition may be applied, e.g., by ink-jet deposition, to an unpatterned substrate. Unpatterned refers to the fact that the surface energy (surface tension) of the substrate has not been intentionally patterned for the sole purpose of confining the composition. It is to be understood that variations in surface energy (used synonymously herein with surface tension) of the substrate associated with devices, interconnects, vias, resists and any other functional features may already be present. For substrates with surface tensions of less than about 30 dynes/cm, a hydrophilic metal nanoparticle composition may be based on ethanol, glycerol, ethylene glycol, and other solvents or liquids having surface tensions of greater than about 30 dynes/cm, more preferably greater than about 40 dynes/cm and preferably greater than about 50 dynes/cm and even greater than about 60 dynes/cm. For substrates with surface tensions of less than about 40 dynes/cm, the solvents should have surface tensions of greater than about 40 dynes/cm, preferably greater than about 50 dynes/cm and even more preferably greater than about 60 dynes/cm. For substrates with surface tensions of less than about 50 dynes/cm, the surface tension of the metal nanoparticle composition should be greater than about 50 dynes/cm, preferably greater than about 60 dynes/cm. Alternatively, the surface tension of the composition can for example be chosen to be at least about 5 dynes/cm, at least about 10 dynes/cm, at least about 15 dynes/cm, at least about 20 dynes/cm, or at least about 25 dynes/cm greater than that of the substrate. Continuous ink jet heads often require surface tensions of about 40 to about 50 dynes/cm. Bubble-jet ink jet heads often require surface tensions of about 35 to about 45 dynes/cm. The previously described methods are particularly preferred for these types of deposition approaches.
  • [0145]
    In another aspect, a metal nanoparticle composition may be applied, e.g., by ink-jet deposition, to an unpatterned low surface energy (hydrophobic) surface that has been surface modified to provide a high surface energy (hydrophilic). The surface energy can be increased by hydroxylating the surface by various means known to those of skill in the art including exposing to oxidizing agents and water, heating in moist air and the like. The surface tension of the metal nanoparticle composition can then, for example, be chosen to be at least about 5, at least about 10, at least about 15, at least about 20, or at least about 25 dynes/cm lower than that of the substrate. Piezo-jet ink jet heads operating with hot wax often require surface tensions of about 25 to about 30 dynes/cm. Piezo-jet ink jet heads operating with UV curable inks often require surface tensions of about 25 to about 30 dynes/cm. Bubble-jet ink jet heads operating with UV curable inks often require surface tensions of about 20 to about 30 dynes/cm. Surface tensions of roughly about 20 to about 30 dynes/cm are usually required for piezo-based ink jet heads using solvents. The previously described methods are particularly preferred for these types of applications.
  • [0146]
    Most electronic substrates with practical applications have low values of surface tension, in the range of from about 18 (polytetrafluoroethylene) to about 45 dynes/cm, often from about 20 to about 40 dynes/cm. In one approach of confining a metal nanoparticle composition to a narrow line or other shape, a hydrophilic pattern corresponding to the pattern of the desired conductor feature may be formed on the surface of a substrate through the methods discussed herein. A particularly preferred method uses a laser. For example, a laser can be used to remove a hydrophobic surface layer exposing a hydrophilic layer underneath. In one aspect, the hydrophilic material pattern on the surface has a surface energy that is at least about 5, at least about 10, at least about 15, at least about 20, at least about 25, or at least about 30 dynes/cm greater than that of the surrounding substrate. In another aspect, the surface tension of the composition is chosen to be lower than the surface tension of the hydrophilic region but higher than the surface tension of the hydrophobic region. The surface tension of the composition can, for example, be chosen to be at least about 5, at least about 10, at least about 15, at least about 20 or at least about 25 dynes/cm smaller than that of the hydrophilic regions. The surface tension of the composition can be chosen to be about 5, about 10, about 15, about 20, or about 25 dynes/cm higher than that of the hydrophobic regions. In another approach, the surface energy of the composition is higher than the surface energy of both the hydrophobic and hydrophilic regions. The surface tension of the composition may, for example, be chosen to be at least about 5, at least about 10, at least about 15, at least about 20, or at least about 25 dynes/cm higher than that of the hydrophilic regions. The surface tension of the ink may, for example, be chosen to be at least about 5, at least about 10, at least about 15, at least about 20, or at least about 25 dynes/cm smaller than that of the hydrophilic regions. This approach is preferred for aqueous-based metal nanoparticle compositions and compositions with high surface tensions in general. Continuous ink jet heads often require surface tensions of from about 40 to about 50 dynes/cm. Bubble-jet ink jet heads often require surface tensions of from about 35 to about 45 dynes/cm. The previously described methods are particularly preferred for these types of applications that can handle compositions with high surface tensions.
  • [0147]
    In another approach to confining a composition to a narrow feature, a hydrophilic surface, or a hydrophobic surface that is rendered hydrophilic by surface modification, may be patterned with a hydrophobic pattern. In one aspect, the hydrophobic pattern may, for example, have a surface energy that is at least about 5, at least about 10, at least about 15, at least about 20, at least about 25 or at least about 30 dynes/cm smaller than that of the surrounding substrate. This can be done by removing a hydrophilic surface layer using a laser to expose a hydrophobic region underneath. A hydrophobic metal nanoparticle composition may be applied to the hydrophobic surface regions to confine the composition. In another aspect, the hydrophobic composition may, for example, have a surface energy that is at least about 5, at least about 10, at least about 15, at least about 20, at least about 25 or at least about 30 dynes/cm lower than that of the surrounding substrate. In another aspect, the hydrophobic composition may, for example, have a surface energy that is at least about 5, at least about 10, at least about 15, at least about 20, at least about 25 or at least about 30 dynes/cm higher than that of the surrounding substrate. In another aspect, the hydrophobic metal nanoparticle composition may, for example, have a surface energy that is at least about 5, at least about 10, at least about 15, at least about 20, at least about 25 or at least about 30 dynes/cm lower than that of the hydrophobic surface pattern. In another aspect, the hydrophobic nanoparticle composition may, for example, have a surface energy that is at least about 5, at least about 10, at least about 15, at least about 20, at least about 25 or at least about 30 dynes/cm higher than that of the hydrophobic surface pattern. In another aspect, the surface tension of the composition may be smaller than that of the hydrophilic regions and greater than that of the hydrophobic regions. The hydrophilic surface may, for example, have a surface tension of greater than about 40, greater than about 50 or greater than about 60 dynes/cm. When the hydrophobic surface has a surface energy of greater than about 40 dynes/cm, it is preferred to use a composition with a surface tension of less than about 40, even less than about 30 dynes/cm, or less than about 25 dynes/cm. When the hydrophobic surface has a surface energy of greater than about 50 dynes/cm, it is preferred to use a composition with a surface tension of less than about 50, preferably less than about 40, even less than about 30 dynes/cm, and more preferably less than about 25 dynes/cm. When the hydrophobic surface has a surface tension of greater than about 40 dynes/cm, it is preferred to use a composition with a surface tension of less than about 40, less than about 35, less than about 30 and even less than about 25 dynes/cm.
  • [0148]
    For ink-jet heads and other deposition techniques that require surface tensions greater than about 30 dynes/cm, a particularly preferred method for confining a metal nanoparticle composition to a surface involves increasing the hydrophilicity of the surface to provide a surface tension greater than about 40, greater than about 45 or greater than about 50 dynes/cm and then providing a hydrophobic surface pattern with a surface tension that is lower than that of the surrounding surface. For example, the surface tension of the pattern may be at least about 5, at least about 10, at least about 15, at least about 20 or at least about 25 dynes/cm higher than the surface tension of the surrounding substrate.
  • [0149]
    Surfactants, i.e., molecules with hydrophobic tails corresponding to lower surface tension and hydrophilic ends corresponding to higher surface tension may be used to modify the compositions and substrates to achieve the required values of surface tensions and interfacial energies.
  • [0150]
    For the purposes of this application, hydrophobic means a material that repels water. Hydrophobic materials have low surface tensions. They also do not have functional groups for forming hydrogen bonds with water.
  • [0151]
    Hydrophilic means a material that has an affinity for water. Hydrophilic surfaces are wetted by water. Hydrophilic materials also have high values of surface tension. They can also form hydrogen bonds with water. The surface tensions for different liquids are listed in Table 1 and the surface energies for different solids are listed in Table 2.
    TABLE 1
    Surface Tensions of Various Liquids
    Surface Tension
    Liquid Temp (° C.) (dynes/cm)
    Water 20 72.75
    Acetamide 85 39.3
    Acetone 20 23.7
    Acetonitrile 20 29.3
    n-Butanol 20 24.6
    Ethanol 20 24
    Hexane 20 18.4
    Isopropanol 20 22
    Glycerol 20 63.4
    Ethylene 20 47.7
    glycol
    Tolulene 20 29
  • [0152]
    TABLE 2
    Surface Energies of Various Solids
    Surface Energy
    Material (dynes/cm)
    Glass 30
    PTFE 18
    Polyethylene 31
    Polyvinychloride 41
    Polyvinylidene 25
    fluoride
    Polypropylene 29
    Polystyrene 33
    Polyvinylchloride 39
    Polysulfone 41
    Polycarbonate 42
    Polyethylene 43
    terephthalate
    Polyacrylonitrile 44
    Cellulose 44
  • [0153]
    Deposition of Metal Nanoparticle Compositions
  • [0154]
    The metal nanoparticle compositions of the present invention can be deposited onto surfaces using a variety of tools such as, e.g., low viscosity deposition tools. As used herein, a low viscosity deposition tool is a device that deposits a liquid or liquid suspension onto a surface by ejecting the composition through an orifice toward the surface without the tool being in direct contact with the surface. The low viscosity deposition tool is preferably controllable over an x-y grid, referred to herein as a direct-write deposition tool. A preferred direct-write deposition tool according to the present invention is an ink-jet device. Other examples of direct-write deposition tools include aerosol jets and automated syringes, such as the MICROPEN tool, available from Ohmcraft, Inc., of Honeoye Falls, N.Y.
  • [0155]
    For use in an ink-jet, the viscosity of the metal nanoparticle composition of the present invention preferably is not greater than about 50 cP, e.g., in the range of from about 10 to about 40 cP. For use in an aerosol jet atomization, the viscosity is preferably not greater than about 20 cP. Automated syringes can use compositions having a higher viscosity, such as up to about 5000 cP.
  • [0156]
    A preferred direct-write deposition tool for the purposes of the present invention is an ink-jet device. Ink-jet devices operate by generating droplets of the composition and directing the droplets toward a surface. The position of the ink-jet head is carefully controlled and can be highly automated so that discrete patterns of the composition can be applied to the surface. Ink-jet printers are capable of printing at a rate of about 1000 drops per jet per second or higher and can print linear features with good resolution at a rate of about 10 cm/sec or more, up to about 1000 cm/sec. Each drop generated by the ink-jet head includes approximately 25 to about 100 picoliters of the composition, which is delivered to the surface. For these and other reasons, ink-jet devices are a highly desirable means for depositing materials onto a surface.
  • [0157]
    Typically, an ink-jet device includes an ink-jet head with one or more orifices having a diameter of not greater than about 100 μm, such as from about 50 μm to about 75 μm. Droplets are generated and are directed through the orifice toward the surface being printed. Ink-jet printers typically utilize a piezoelectric driven system to generate the droplets, although other variations are also used. Ink-jet devices are described in more detail in, for example, U.S. Pat. Nos. 4,627,875 and 5,329,293, the disclosures whereof are incorporated by reference herein in their entireties.
  • [0158]
    It is also expedient to simultaneously control the surface tension and the viscosity of the metal nanoparticle composition to enable the use of industrial ink-jet devices. Preferably the surface tension is from about 10 to about 50 dynes/cm, such as from about 20 to about 40 dynes/cm, while the viscosity is maintained at a value of not greater than about 50 centipoise.
  • [0159]
    According to one aspect, the solids loading of particles in the metal nanoparticle composition is preferably as high as possible without adversely affecting the viscosity or other desired properties of the composition. As set forth above, a metal nanoparticle composition according to the present invention preferably has a particle loading of not higher than about 75 weight percent, e.g., from about 5 to about 50 weight percent.
  • [0160]
    The metal nanoparticle compositions of the present invention which are intended for use in an ink-jet device may also include surfactants to maintain the particles in suspension. Co-solvents, also known as humectants, can be used to prevent the metal nanoparticle composition from crusting and clogging the orifice of the ink-jet head. Biocides can also be added to prevent bacterial growth over time. Non-limiting examples of corresponding ink-jet liquid vehicle compositions are disclosed in, e.g., U.S. Pat. Nos. 5,853,470; 5,679,724; 5,725,647; 4,877,451; 5,837,045 and 5,837,041, the entire disclosures whereof are incorporated by reference herein. The selection of such additives is based upon the desired properties of the composition, as is known to those skilled in the art. As set forth above, if the composition is intended for the fabrication of electrically conductive features, care should be taken that the additives of the composition do not have a significant adverse effect on the conductivity of the final feature and/or can be removed easily.
  • [0161]
    The metal nanoparticle compositions according to the present invention can also be deposited by aerosol jet deposition. Aerosol jet deposition allows the formation of conductive features having a feature width of, e.g., not greater than about 200 μm, such as not greater than about 150 μm, not greater than about 100 μm and even not greater than about 50 μm. In aerosol jet deposition, the metal nanoparticle composition is aerosolized into droplets and the droplets are transported to the substrate in a flow gas through a flow channel. Typically, the flow channel is straight and relatively short.
  • [0162]
    The aerosol can be created using a number of atomization techniques. Examples include ultrasonic atomization, two-fluid spray head, pressure atomizing nozzles and the like. Ultrasonic atomization is preferred for compositions with low viscosities and low surface tension. Two-fluid and pressure atomizers are preferred for higher viscosity fluids. Solvent or can be added to the metal nanoparticle composition during atomization, if necessary, to keep the concentration of metal nanoparticle components substantially constant during atomization.
  • [0163]
    The size of the aerosol droplets can vary depending on the atomization technique. In one aspect, the average droplet size is not greater than about 10 μm, e.g., not greater than about 5 μm. Large droplets can be optionally removed from the aerosol, such as by the use of an impactor.
  • [0164]
    Low aerosol concentrations require large volumes of flow gas and can be detrimental to the deposition of fine features. The concentration of the aerosol can optionally be increased, such as by using a virtual impactor. The concentration of the aerosol may be greater than about 106 droplets/cm3, e.g., greater than about 107 droplets/cm3. The concentration of the aerosol can be monitored and the information can be used to maintain the mist concentration within, for example, about 10% of the desired mist concentration over a period of time.
  • [0165]
    The droplets may be deposited onto the surface of the substrate by inertial impaction of larger droplets, electrostatic deposition of charged droplets, diffusional deposition of sub-micron droplets, interception onto non-planar surfaces and settling of droplets, such as those having a size in excess of about 10 μm.
  • [0166]
    Examples of tools and methods for the deposition of fluids using aerosol jet deposition include those disclosed in U.S. Pat. Nos. 6,251,488; 5,725,672 and 4,019,188, the entire disclosures whereof are incorporated by reference herein.
  • [0167]
    The metal nanoparticle compositions of the present invention can also be deposited by a variety of other techniques including intaglio, roll printer, spraying, dip coating, spin coating, and other techniques that direct discrete units of fluid or continuous jets, or continuous sheets of fluid to a surface. Other examples of advantageous printing methods for the compositions of the present invention include lithographic printing and gravure printing. For example, gravure printing can be used with metal nanoparticle compositions having a viscosity of up to about 5,000 centipoise. The gravure method can deposit features having an average thickness of from about 1 μm to about 25 μm and can deposit such features at a high rate of speed, such as up to about 700 meters per minute. The gravure process also comprises the direct formation of patterns onto the surface.
  • [0168]
    Lithographic printing methods can also be utilized with the nanoparticle compositions of the present invention. In the lithographic process, the inked printing plate contacts and transfers a pattern to a rubber blanket and the rubber blanket contacts and transfers the pattern to the surface being printed. A plate cylinder first comes into contact with dampening rollers that transfer an aqueous solution to the hydrophilic non-image areas of the plate. A dampened plate then contacts an inking roller and accepts the ink only in the oleophilic image areas.
  • [0169]
    Using one or more of the foregoing deposition techniques, it is possible to deposit the metal nanoparticle composition on one side or both sides of a substrate. Further, the processes can be repeated to deposit multiple layers of the same or different metal nanoparticle compositions on a substrate.
  • [0170]
    An optional first step may comprise a surface modification of the substrate as is discussed above. The surface modification may be applied to the entire substrate or may be applied in the form of a pattern, such as by using photolithography. The surface modification may, for example, include increasing or decreasing the hydrophilicity of the substrate surface by chemical treatment. For example, a silanating agent can be used on the surface of a glass substrate to increase the adhesion and/or to control spreading of the metal nanoparticle composition through modification of the surface tension and/or wetting angle. The surface modification may also include the use of a laser to clean the substrate. The surface may also be subjected to mechanical modification by contacting with another type of surface. The substrate may also be modified by corona treatment.
  • [0171]
    For example, a line of polyimide can be printed prior to deposition of a metal nanoparticle composition, such as a silver metal nanoparticle composition, to prevent infiltration of the composition into a porous substrate, such as paper. In another example, a primer material may be printed onto a substrate to locally etch or chemically modify the substrate, thereby inhibiting the spreading of the metal nanoparticle composition being deposited in the following printing step. In yet another example, a via can be etched by printing a dot of a chemical that is known to etch the substrate. The via can then be filled in a subsequent printing process to connect circuits being printed on the front and back of the substrate.
  • [0172]
    As is discussed above, the deposition of a metal nanoparticle composition according to the present invention can be carried out, for example, by pen/syringe, continuous or drop on demand ink-jet, droplet deposition, spraying, flexographic printing, lithographic printing, gravure printing, other intaglio printing, and others. The metal nanoparticle composition can also be deposited by dip-coating or spin-coating, or by pen dispensing onto rod or fiber type substrates. Immediately after deposition, the composition may spread, draw in upon itself, or form patterns depending on the surface modification discussed above. In another aspect, a method is provided for processing the deposited composition using 2 or more jets or other ink sources. An example of a method for processing the deposited composition is using infiltration into a porous bed formed by a previous fabrication method. Another exemplary method for depositing the composition is using multi-pass deposition to build the thickness of the deposit. Another example of a method for depositing the composition is using a heated head to decrease the viscosity of the composition.
  • [0173]
    The properties of the deposited metal nanoparticle composition can also be subsequently modified. This can include freezing, melting and otherwise modifying the properties such as viscosity with or without chemical reactions or removal of material from the metal nanoparticle composition. For example, a metal nanoparticle composition including a UV-curable polymer can be deposited and immediately exposed to an ultraviolet lamp to polymerize and thicken and reduce spreading of the composition. Similarly, a thermoset polymer can be deposited and exposed to a heat lamp or other infrared light source.
  • [0174]
    After deposition, the metal nanoparticle composition may be treated to convert the metal nanoparticle composition to the desired structure and/or material, e.g., a conductive feature. The treatment can include multiple steps, or can occur in a single step, such as when the metal nanoparticle composition is rapidly heated and held at the processing temperature for a sufficient amount of time to form a conductive feature.
  • [0175]
    An optional, initial step may include drying or subliming of the composition by heating or irradiating. In this step, material (e.g., solvent) is removed from the composition and/or chemical reactions occur in the composition. Non-limiting examples of methods for processing the deposited composition in this manner include methods using a UV, infrared (IR), laser or a conventional light source. Heating rates for drying the metal nanoparticle composition are preferably greater than about 10° C./min, more preferably greater than about 100° C./min and even more preferably greater than about 1000° C./min. The temperature of the deposited metal nanoparticle composition can be raised using hot gas or by contact with a heated substrate. This temperature increase may result in further evaporation of vehicle and other species. A laser, such as an IR laser, can also be used for heating. An IR lamp, a hot plate or a belt firnace can also be utilized. It may also be desirable to control the cooling rate of the deposited feature.
  • [0176]
    The metal nanoparticle compositions of the present invention can be processed for very short times and still provide useful materials. Short heating times can advantageously prevent damage to the underlying substrate. For example, thermal processing times for deposits having a thickness on the order of about 10 μm may be not greater than about 100 milliseconds, e.g., not greater than about 10 milliseconds, or not greater than about 1 millisecond. The short heating times can be provided using laser (pulsed or continuous wave), lamps, or other radiation. Particularly preferred are scanning lasers with controlled dwell times. When processing with belt and box furnaces or lamps, the hold time may often be not longer than about 60 seconds, e.g., not longer than about 30 seconds, or not longer than about 10 seconds. The heating time may even be not greater than about 1 second when processed with these heat sources, and even not greater than about 0.1 second while still providing conductive materials that are useful in a variety of applications. The preferred heating time and temperature will also depend on the nature of the desired feature, e.g., of the desired electronic feature. It will be appreciated that short heating times may not be beneficial if the solvent or other constituents boil rapidly and form porosity or other defects in the feature.
  • [0177]
    By way of non-limiting example, a printed feature in accordance with the present invention may be cured by a number of different methods including thermal, UV and pressure-based curing. The thermal curing can be effected by removing the solvents at low temperatures and creating a reflective print. On some substrates such as paper, no thermal curing step may be necessary at all, while in others a mild thermal curing step such as short exposure to an IR lamp may be sufficient. In this particular embodiment, the metallic ink has a higher absorption cross-section for the IR energy derived from the lamp than the surrounding substrate and so the printed metallic feature is preferentially thermally cured.
  • [0178]
    In cases where the ink contains a photoactive reagent a printed metallic feature in accordance with the present invention may also be cured by irradiation with UV light. The photoactive reagent may, for example, be a monomer or low molecular weight polymer which polymerizes on exposure to UV light resulting in a robust, insoluble metallic layer. In cases where electric conductivity is important, a photoactive metal species may, for example, be incorporated into the ink to provide good connectivity between the nanoparticles in the ink after curing. In this embodiment, the photoactive metal-containing species is photochemically reduced to form the corresponding metal.
  • [0179]
    In a flurther aspect of the present invention, the printed metallic ink may be cured by compression. This can be achieved by exposing the substrate containing the printed feature to any of a variety of different processes that “weld” the nanoparticles in the ink. Non-limiting examples of these processes include stamping and roll pressing. For example, for applications in the security industry, subsequent processing steps in the construction of a secure document are likely to include intaglio printing which will result in the exposure of the substrate containing the printed metallic feature to high pressure and temperatures in the range of from about 50° C. to about 100° C. The temperature or the pressure or both combined will usually be sufficient to cure the metallic ink and create a reflective and/or conductive feature. Of course, any combination of heating, pressing and UV-curing may be used for curing a printed feature in accordance with the present invention.
  • [0180]
    In one aspect of the present invention, the deposited metal nanoparticle composition may be converted to an electrically conductive feature at temperatures of not higher than about 300° C., e.g., not higher than about 250° C., not higher than about 225° C., not higher than about 200° C., or even not higher than about 185° C. In many cases it will be possible to achieve substantial conductivity at temperatures of not higher than about 150° C., e.g., at temperatures of not higher than about 125° C., or even at temperatures of not higher than about 100° C. Any suitable method and device and combinations thereof can be used for the conversion, e.g., heating in a furnace or on a hot plate, irradiation with a light source (UV lamp, IR or heat lamp, laser, etc.), combinations of any of these methods, to name just a few.
  • [0181]
    By way of non-limiting example, after heating to a temperature of about 200° C., or even to a temperature of about 150° C., a deposited composition of the present invention may show a resistivity which is not higher than about 30 times, e.g., not higher than about 20 times, not higher than about 10 times, or not higher than about 5 times the resistivity of the pure bulk metal.
  • [0182]
    The particles in the metal nanoparticle composition may optionally be (fully) sintered. The sintering can be carried out using, for example, furnaces, light sources such as heat lamps and/or lasers. In one aspect, the use of a laser advantageously provides very short sintering times and in one aspect the sintering time is not greater than about 1 second, e.g., not greater than about 0.1 seconds, or even not greater than about 0.01 seconds. Laser types include pulsed and continuous wave lasers. In one aspect, the laser pulse length is tailored to provide a depth of heating that is equal to the thickness of the material to be sintered.
  • [0183]
    It will be appreciated from the foregoing discussion that two or more of the latter process steps (drying, heating and sintering) can be combined into a single process step. Also, one or more of these steps may optionally be carried out in a reducing atmosphere (e.g., in an H2/N2 atmosphere for metals that are prone to undergo oxidation, especially at elevated temperature, such as e.g., Ni) or in an oxidizing atmosphere.
  • [0184]
    The deposited and treated material, e.g., a conductive feature may be post-treated. The post-treatment can, for example, include cleaning and/or encapsulation of the conductive feature (e.g., in order to protect the deposited material from oxygen, water or other potentially harmful substances) or other modifications. The same applies to any other metal structures that may be formed (e.g., deposited) with a nanoparticle composition of the present invention.
  • [0185]
    One exemplary process flow includes the steps of: forming a structure by conventional methods such as lithographic, gravure, flexo, screen printing, photo patterning, thin film or wet subtractive approaches; identifying locations requiring addition of material; adding material by a direct deposition of a low viscosity composition; and processing to form the final product. In a specific aspect, a circuit may be prepared by, for example, screen-printing and then be repaired by localized printing of a low viscosity metal nanoparticle composition of the present invention.
  • [0186]
    More specifically, the present invention also provides a method for the repair of a feature by, e.g., ink-jet printing or syringe dispensing. In one aspect, the method includes the steps of ink-jet printing a metal nanoparticle composition of the present invention onto a repair region and heating to temperatures sufficient to convert the metal nanoparticle composition to a conductor. According to one aspect of the present invention, the repair feature is a ball grid array (BGA). According to another aspect, the feature is a circuit pattern in a low temperature co-fire ceramic (LTCC) layer. In one aspect, the pattern is not yet sintered while in another aspect the pattern is already sintered. In one aspect, a laser can be used to heat the repair section. The repair can be carried out prior to processing of the part. The repair can be made to a metallic conductor or other electronic feature. The repaired portion can have been formed by screen-printing or photo-patterning of a particle-containing composition. In one aspect, laser trimming is used to further define the repair region after ink-jet deposition.
  • [0187]
    According to one aspect of the present invention, the repaired feature preferably has a minimum feature size that is not greater than about 250 μm and more preferably is not greater than about 100 μm. According to one aspect, the repaired feature has a minimum feature size not greater than about 10 μm. The repair can be made to features derived from various processes such as chemical vapor deposition, evaporation, sputtering or other thin film techniques.
  • [0188]
    In another aspect, features larger than approximately 100 μm are first prepared by screen-printing. Features not greater than about 100 μm are then deposited by a direct deposition method using a metal nanoparticle composition of the present invention.
  • [0189]
    Preferably, a conductive feature made with a composition of the present invention has a resistivity that is not greater than about 20 times the bulk resistivity of the pure metal, e.g., not greater than about 10 times the bulk resistivity, not greater than about 5 times the bulk resistivity, or even not greater than about 2 times the bulk resistivity of the pure metal.
  • [0190]
    In accordance with the direct-write processes, the present invention comprises the formation of features for devices and components having a small minimum feature size. For example, the method of the present invention can be used to fabricate features having a minimum feature size (the smallest feature dimension in the x-y axis) of not greater than about 200 μm, e.g., not greater than about 150 μm, or not greater than about 100 μm. These feature sizes can be provided using ink-jet printing and other printing approaches that provide droplets or discrete units of composition to a surface. The small feature sizes can advantageously be applied to various components and devices, as is discussed below.
  • [0191]
    Ink Curing and Processing
  • [0192]
    A nanoparticle composition of the present invention which has been applied (e.g., printed) on a substrate may be cured by a number of different methods including, but not limited to thermal, UV and pressure-based curing. By way of non-limiting example, thermal curing can be effected by removing the vehicle (solvents) at low temperatures and creating a reflective print. On some substrates such as paper, no thermal curing step may be necessary, while in others a mild thermal curing step such as, e.g., short exposure to an infra-red lamp may be sufficient. In this particular embodiment, the metallic ink may have a higher absorption cross-section for the IR energy derived from the heat lamp compared to the surrounding substrate and so the applied composition may be preferentially thermally cured.
  • [0193]
    The applied composition (e.g., a printed feature) may also be cured by irradiation with UV light where the ink contains a photoreactive reagent. The photoreactive reagent may, for example, be a monomer or low molecular weight polymer which polymerizes on exposure to UV light resulting in a robust, insoluble metallic layer. In cases where electronic conductivity is important, a photoreactive metal species may be incorporated into the ink to provide good connectivity between the nanoparticles in the ink after curing. In this particular embodiment, the photoactive metal-containing species is photochemically reduced to form the corresponding metal.
  • [0194]
    According to a further non-limiting example, the applied (e.g., printed) composition may be cured by compression. This may be achieved, for example, by exposing the article comprising the applied composition to any of a variety of different processes that “weld” the nanoparticles in the composition (ink). Non-limiting examples of corresponding processes include stamping and roll pressing. In particular, for applications in the security industry (discussed in detail below), subsequent processing steps in the construction of a secure document may include intaglio printing which will result in the exposure of a substrate comprising a deposited metallic feature to high pressure and temperatures in the range of from, e.g., about 50° C. to about 100° C. The temperature or the pressure or both combined should be sufficient to cure the metallic ink and create a reflective and/or conductive feature.
  • [0195]
    It will be appreciated by those skilled in the art that any combination of heating, pressing, UV-curing or any other type of radiation curing may be useful in creating desired properties of a (e.g., printed) feature.
  • [0196]
    A metal nanoparticle composition (ink) of the present invention comprises two basic components: particles and a liquid vehicle. The liquid vehicle provides the liquid properties to the ink, enabling it to be printed and dispensed onto the substrate. The nanoparticles have two main components: a metal core and a preferably organic surface material in the form of, e.g., a surface layer, capping, coating, or shell (anti-agglomeration substance). The organic surface material preferably stabilizes the particles, preventing agglomeration in the liquid phase and providing surface functionality that enables a stable dispersion in the liquid vehicle. After printing, the liquid vehicle is removed (evaporated) and the organic surface material no longer is needed for any of these functions. In fact, the organic material can now be considered an obstacle for sintering of the metallic particles, inhibiting charge transport. In a particularly preferred aspect of the present invention, the organic surface material is attached to (adsorbed on) the metal nanoparticle in a dative manner, allowing sintering at very low temperatures (for example, in the range of from about 100° C. to about 150° C.). This means that the organic surface material will not evaporate or otherwise become volatile and leave the printed feature at these low temperatures. Instead, the organic material is assumed to move out of the way, allowing the metal particles to touch and sinter together, while a substantial amount of the organic material remains present as part of the printed feature. In another preferred aspect, the organic material (polymer) may assume a new function: it may promote adhesion of the printed metal structure to a range of organic and polymeric substrates such as, e.g., paper, FR4 or Mylar® (PET) and provide structural strength. As a result of the low-temperature sintering mechanism, a continuous percolation network may be formed that provides continuous channels for the conduction of electrons to flow throughout the printed structure without obstacles.
  • [0197]
    When high conductivity and a dense, high metal-content material are desired, a higher-temperature sintering may be performed (for example, in the range of from about 300° C. to about 550° C.). During such treatment the organic surface material may—at least in part—volatilize. As a result, sintering will occur more rapidly and a much denser metal structure may be formed as compared to a low-temperature structure.
  • [0198]
    After an ink is printed on the substrate, it may be heated to yield the desired electrical performance, adhesion, and abrasion resistance. This heating can be accomplished in a variety of ways such as hot plate, convection oven, infrared radiation, laser radiation, UV exposure, etc. In general, the resistivity of a printed structure will drop with curing temperature and curing time. In one aspect, the detailed time-temperature profile may play a role in the final electrical performance of the printed line or feature: by way of non-limiting example, drying the ink at about 80° C. before heating it to about 120° C. may in some cases result in a feature with a significantly lower conductivity than that of a feature that was printed and immediately heated to about 120° C. without allowing it to dry.
  • [0199]
    The electrical performance of a cured printed line is often described in terms of the bulk resistivity of the cured line. These values are obtained by measuring the resistance (R) of the printed line, the length (l), and the average cross sectional area (width times thickness: w.d). The bulk resistivity (ρ) is calculated using the equation: ρ(Ω cm)=R (Ω) X w.d/l (cm). The most accurate data are obtained when using the ratiometric resistance measurement procedure which eliminates contact resistance. When adequate sensing probes are used that do not damage the printed metal, in combination with printed contact pads, a two-point probe measurement can also be used to provide reliable data.
  • [0200]
    In a preferred aspect of the present invention the peak curing temperature and the curing time are the main factors that determine the ultimate electrical performance of the printed metals. In addition, secondary parameters such as heating profile (ramp rate, drying or no drying prior to heating), substrate type (e.g., coated paper, PET, glass, etc.) curing ambient, and heating method (e.g., oven, laser, IR, etc.) may also play a role.
  • [0201]
    In a preferred aspect of the present invention, high conductivity can be achieved after very short curing times at temperatures above about 200° C. For example, a 60 second cure at 300° C. may yield a printed Ag line with a bulk resistivity value of about 3.8 μΩ cm. In another example, high electrical conductivity can be accomplished with curing times in the single digit second range at temperatures of from about 250° C. to about 550° C. Curing processes such as in-line RTP (rapid thermal processing) can be used to cure the printed features after printing and achieve the desired electrical properties. This will enable a significant reduction in tact time in a manufacturing process when compared to competing materials and processes.
  • [0202]
    In another preferred aspect of the present invention, the organic material may be attached to the metal nanoparticles in a dative manner. When low temperature sintering is performed (e.g., in the range of from about 75° C. to about 250° C.), the organic material will usually not evaporate or otherwise become volatile and leave the printed feature. Instead, it is assumed that the organic material moves out of the way, allowing the metal particles to touch and sinter together, while a substantial amount of the organic material remains present as part of the printed feature. In a preferred aspect of the present invention, the resulting material may be a nanocomposite which comprises a substantially uniform mixture of metal and organic material. Both phases (metal, organic material) may form substantially uniform inclusions with a size in the range of from, e.g., about 5 nm to about 60 nm. In an even more preferred aspect, the metal inclusions may be physically necked together, forming an interconnected percolation network. The organic component of the composite may, for example, represent not more than about 50% by volume of the nanocomposite, e.g., not more than about 45% by volume, not more than about 40% by volume, not more than about 35% by volume, or not more than about 25% by volume of the total nanocomposite.
  • [0203]
    In one embodiment, the invention relates to an ink, comprising a liquid vehicle; and metallic nanoparticles in an amount greater than about 40 weight percent, based on the total weight of the ink. Such an ink is suitable for direct write printing applications. In some embodiments, the nanoparticles comprise nanoparticles prepared by a process which comprises a reduction of a metal compound by a polyol. In other embodiments, the ink comprises at least about 10 weight percent of the nanoparticles.
  • [0204]
    In some embodiments, at least about 90% of the nanoparticles in the ink are of substantially spherical shape. In other embodiments, at least about 90% of the nanoparticles in the ink have a particle size of not more than about 80 nm. In still other embodiments, at least about 80% of the nanoparticles in the ink have a particle size in the range of from about 10 nm to about 70 nm. In yet other embodiments, the ink is substantially free of particles having a particle size of more than about 100 nm. In one embodiment, the metallic nanoparticles in the ink have an average particle size of less than about 500 nm or less than about 100 nm.
  • [0205]
    In some embodiments, the metallic nanoparticles in the ink comprise a metal selected from the group consisting of silver, gold, platinum, palladium, iron, nickel, copper, rhodium and alloys thereof. Preferably, the ink comprises silver.
  • [0206]
    In some embodiments, the ink comprises the metallic nanoparticles in an amount greater than about 50 weight percent or in an amount greater than about 60 weight percent, based on the total weight of the ink. In other embodiments, the ink comprises the metallic nanoparticles in an amount greater than about 40 weight percent and less than about 90 weight percent or in an amount from about 50 to about 80 weight percent, based on the total weight of the ink. In a preferred embodiment, the ink has a surface tension of from about 25 to about 70 dynes/cm.
  • [0207]
    In one embodiment, the liquid vehicle has a surface tension, in the absence of the nanoparticles, of from about 25 to about 70 dynes/cm. In other embodiments, the ink has a surface tension at 20° C. of not higher than about 30 cPs. In still other embodiments, the ink has a surface tension at 20° C. of not higher than about 40 dynes/cm.
  • [0208]
    In one embodiment, the ink has a viscosity of from about 8 to about 25 centipoise. In one embodiment, the the liquid vehicle has a viscosity, in the absence of the nanoparticles, of from about 1 to about 25 cPs.
  • [0209]
    In a preferred embodiment, the ink has substantially no sedimentation after 7 days at room temperature.
  • [0210]
    In some embodiments, the ink may further comprise an agglomeration-preventing substance, the agglomeration-preventing substance comprising an organic substance. In some embodiments, the agglomeration-preventing substance comprises a polymer. In some embodiments, the polymer comprises a polymer of vinyl pyrrolidone (e.g., vinyl pyrrolidone homopolymer).
  • [0211]
    In other embodiments, the vehicle in the ink is capable of dissolving the agglomeration-preventing substance. In one embodiment, the vehicle capable of dissolving the agglomeration-preventing substance comprises water. In other embodiments, the vehicle comprises in the ink comprises ethanol, ethylene glycol and glycerol. In such cases, the vehicle comprises from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on a total weight of the vehicle.
  • [0212]
    Conductor Properties and Structure
  • [0213]
    The conductors formed by the compositions and methods of the present invention may have combinations of various characteristics. The conductive features preferably have a high purity, a high electrical conductivity and/or high electromigration resistance. High conductivity can, for example, be provided through compositions comprising nanoparticles of, e.g., silver, platinum, palladium, gold, nickel and/or copper.
  • [0214]
    It will be appreciated that the properties of the conductive feature may vary depending upon the particular application. For example, where a relatively low conductivity is acceptable it may be desirable for some applications to process the deposited feature at a very low temperature. According to one aspect, a metal nanoparticle composition may be deposited and processed at a temperature of not greater than 125° C., where the resistivity of the feature is not greater than about 100 times the resistivity of the pure bulk metal, more preferably not greater than about 50 times the resistivity of the bulk metal and even more preferably not greater than about 30 times the resistivity of the bulk metal.
  • [0215]
    After heating, the compositions of the present invention may yield solids with specific bulk resistivity values. As a background, bulk resistivity values of a number of solids are provided in Table 3.
    TABLE 3
    Bulk Resistivity of Various Materials
    Bulk Resistivity
    Material (micro-Ω cm)
    Silver (Ag - thick film material fired at 850° C.) 1.59
    Copper (Cu) 1.68
    Gold (Au) 2.24
    Aluminum (Al) 2.64
    Ferro CN33-246 (Ag + low melting glass, fired at 2.7-3.2
    150° C.)
    SMP Ag flake + metal nanoparticle formulation, 4.5
    250° C.
    Molybdenum (Mo) 5.2
    Tungsten (W) 5.65
    Zinc (Zn) 5.92
    Nickel (Ni) 6.84
    Iron (Fe) 9.71
    Palladium (Pd) 10.54
    Tin (Sn) 11
    Solder (Pb—Sn; 50:50) 15
    Lead 20.64
    Titanium nitrate (TiN transparent conductor) 20
    5029 (state of the art Ag filled polymer, 150° C.) 18-50
    DuPont Polymer Thick Film (Cu filled polymer)  75-300
    ITO (In2O3:Sn) 100
    Zinc oxide (ZnO doped-undoped) 120-450
    Carbon (C-graphite) 1375
    KIA SCC-10 (doped silver phosphate glass, 330° C. 3000
    soft point)
    Ruthenium oxide RuO2 type conductive oxides   5000-10,000
    Bayer conductive polymer Baytron-P 1,000,000
  • [0216]
    The compositions and methods of the present invention advantageously allow the fabrication of various unique structures.
  • [0217]
    In one aspect, the average thickness of the deposited structure (feature) may be greater than about 0.01 μm, e.g., greater than about 0.05 μm, greater than about 0.1 μm, or greater than about 0.5 μm. The thickness can even be greater than about 1 μm, such as greater than about 5 μm. These thicknesses can be obtained by ink-jet deposition or deposition of discrete units of material in a single pass or in two or more passes. For example, a single layer can be deposited and dried, followed by one or more repetitions of this cycle, if desired.
  • [0218]
    Vias can also be filled with the metal nanoparticle compositions of the present invention. For example, the via can be filled, dried to remove the volume of the solvent, filled further and two or more cycles of this type can be used to fill the via. The via may then be processed to convert the material to its final composition. After conversion, it is also possible to add more metal nanoparticle composition, dry and then convert the material to product to replace the volume of material lost upon conversion to the final product.
  • [0219]
    The compositions and methods of the present invention can also be used to form dots, squares and other isolated regions of material. The regions can have a minimum feature size of not greater than about 250 μm, such as not greater than about 100 μm, and even not greater than about 50 μm, such as not greater than about 25 μm, or not greater than about 10 μm. These features can be deposited by ink-jet printing of a single droplet or multiple droplets at the same location with or without drying in between deposition of droplets or periods of multiple droplet deposition. In one aspect, the surface tension of the metal nanoparticle composition on the substrate material may be chosen to provide poor wetting of the surface so that the composition contracts onto itself after printing. This provides a method for producing deposits with sizes equal to or smaller than the droplet diameter.
  • [0220]
    The compositions and methods of the present invention can also be used to form lines. In one aspect, the lines can advantageously have an average width of not greater than about 250 μm, such as not greater than about 200 μm, not greater than about 150 μm, not greater than about 100 μm, or not greater than about 50 μm.
  • [0221]
    In one aspect of the present invention a line may be formed on a substrate by depositing a metal nanoparticle composition (e.g., a composition comprising silver nanoparticles) on a substrate in not more than two passes of an ink-jet printing head, e.g., in a single pass of the head, which line can be rendered electrically conductive by heating and/or irradiating the line.
  • [0222]
    The compositions and methods of the present invention produce features that have good adhesion to substrates of many different materials, e.g., polymeric materials, cellulose-based materials, textiles, glass, metal and ceramic.
  • [0223]
    In one aspect, the compositions of the present invention can be used to ink-jet print structures with a specifically targeted structure thickness and sheet resistivity (expressed in Ω/sq). An exact amount of metal (e.g., Ag) per unit area can be printed by adjusting the dots per inch (dpi) data contained in the print file, the inkjet drop volume, and the solid loading of the ink. Multiple pass printing can also be used to print thicker layers. Continuous conductive features can be ink-jet printed by adequate drop placement, and by controlling dpi, drop volume, and wetting behavior on the substrate.
  • [0224]
    The schematic in FIG. 1 shows the basic principle of continuous feature ink-jet printing by adequate drop placement, taking into account ink drop volume and wetting behavior on the substrate. The worksheet in FIG. 1 provides an example of how to control the Ag ink thickness and sheet resistivity of an inkjet printed line.
  • [0225]
    In this specific example, lines were ink-jet printing with a Spectra SE-128 head on a photo-paper substrate. The performance of the printed trace compared to the equivalent fully dense feature (optimum performance) yields a correction factor for this particular application. Using this general approach, an application specific scaling factor can be calculated for any application by measuring the sheet resistivity value of a printed feature and correlating it to the other parameters. The application specific formula of the form (0.016×4.2 X μm×Ω/sq)/(A×B×C×E) can then be used to accurately predict the performance of printed features for a specific ink (volume loading), a specific print file (dpi), print head parameters (drop volume), substrate, and curing process (correction factor).
  • [0226]
    In another aspect, the compositions and methods of the present invention can also be used to print multilayer structures. For example, an adhesion material/promoter can be printed prior to printing of the metal structure. By way of non-limiting example, in a preferred aspect of the present invention, a metal, metal oxide, or low melting point glass structure may be ink-jet printed on a glass substrate followed by ink-jet printing of a metal (e.g., silver) structure on top of the first printed structure. After heating, the adhesion material/promoter will improve the adhesion of the metal (Ag) structure to the glass substrate. In another non-limiting example, a metal, metal oxide, or low melting point glass structure may be ink-jet printed on an ITO coated glass substrate followed by ink-jet printing of a metal (e.g., silver) structure on top of the first printed structure. After heating, the adhesion material/promoter structure will improve adhesion of the metal structure to the glass substrate.
  • [0227]
    In another non-limiting example, a black structure may be printed prior to the printing of a metal structure. In a preferred aspect, a carbon containing material and/or a metal oxide (chromium oxide, ruthenium oxide, cobalt oxide, etc.) may be printed in a line on a glass substrate or an ITO coated glass substrate, followed by ink-jet printing of a metal (e.g., silver) line on top of the first printed line. These two printed lines will appear black when viewed through the glass substrate. This is an important feature for flat panel display applications such as plasma displays, where a high contrast ratio between light and dark is required during viewing of the display. In addition, this black structure may in some preferred aspects also enhance the adhesion of the silver layer to the substrate which may be, for example, glass or ITO coated glass.
  • [0228]
    In yet another non-limiting example, a diffusion barrier material may be printed prior to the printing of the metal (e.g., Ag) structure. By way of non-limiting example, a Ni nanoparticle ink layer may be ink-jet printed on top of a Si substrate (crystalline Si, poly Si, or amorphous Si), for example, an amorphous Si electrode or a poly-Si source or drain of a thin film transistor device in an active matrix backplane of a LCD display. A metal (preferably, silver) line or electrode may be subsequently printed on top of the Ni layer. The Ni layer will provide a diffusion barrier for diffusion of Ag into the Si material. This is important as Si contamination is known to interfere with proper Si transistor device operation. It will be appreciated by those skilled in the art that other diffusion barrier materials can be selected, including materials that react with the silicon layer and form a silicide which acts as a diffusion barrier.
  • [0229]
    In yet another non-limiting example, a protective layer may be printed on top of the printed metal (e.g., Ag) structure. This protective layer provides protection against, e.g., chemical agents that are present in the gas or liquid to which the printed structure may be exposed after it is printed. For example, a glass or polymer overcoat may be printed on top of a metal (e.g., Ag) structure to prevent oxidation or blackening of the metal due to exposure to the ambient. In another example, a Ni layer may be printed on top of an Ag structure to prevent corrosion of the Ag during subsequent processing steps. Such processing steps may include liquid etching, gas plasma etching, or other processes which are commonly used in the manufacture of transistors and flat panel displays. It will be appreciated by those skilled in the art that other protective overcoat layer materials may be selected as well.
  • [0230]
    Applications
  • [0231]
    The metal nanoparticle compositions and methods of the present invention may advantageously be used, for example, for the fabrication of printed metallic features which may be electrically conductive or non-conductive, and may be transparent, semi-transparent and/or reflective in the visible light range and/or in any other range such as, e.g., in the UV and/or IR ranges. (The terms “feature” and “structure” as used herein and in the appended claims include any two- or three-dimensional structure including, but not limited to, a line, a dot, a patch, a continuous or discontinuous layer (e.g., coating) and in particular, any structure that is capable of being formed on any substrate.) In particular, the metal nanoparticle compositions and methods of the present invention can be used in a variety of electronic and non-electronic applications such as, e.g., RF ID antennas and tags, digitally printed multi-layer circuit boards, printed membrane keyboards, smart packages, security documents, “disposable electronics” printed on plastics or paper stock, interconnects for applications in printed logic, passive matrix displays, and active matrix backplanes for applications such as OLED displays and TFT AMLCD technology. In the following some non-limiting examples of the types of devices and components to which the methods and compositions of the present invention are applicable will be described in more detail.
  • [0232]
    The compositions and methods of the present invention can be used to fabricate antennas for RF (radio frequency) tags and smart cards. In one aspect, the antenna comprises a material with a sheet resistivity of from about 10 to about 100,000 ohms/square. In another aspect, the antenna comprises a silver conductor with a resistivity that is not greater than three times the resistivity of substantially pure silver.
  • [0233]
    The compositions can also serve as solder replacements. Such compositions can include silver, lead or tin.
  • [0234]
    The compositions and methods can be utilized to provide connection between chips and other components in smart cards and RF tags.
  • [0235]
    In one aspect, the surface to be printed onto is not planar and a non-contact printing approach is used. The non-contact printing approach can be ink-jet printing or another technique providing deposition of discrete units of fluid onto the surface. Examples of surfaces that are non-planar include in windshields, electronic components, electronic packaging and visors.
  • [0236]
    The compositions and methods provide the ability to print disposable electronics such as for games included in magazines. The compositions can advantageously be deposited and reacted on cellulose-based materials such as paper or cardboard. The cellulose-based material can be coated if necessary to prevent bleeding of the metal nanoparticle composition into the substrate. For example, the cellulose-based material could be coated with a UV curable polymer.
  • [0237]
    The compositions and methods can be used to form under-bump metallization, redistribution patterns and basic circuit components.
  • [0238]
    The compositions and methods of the present invention can also be used to fabricate microelectronic components such as multichip modules, particularly for prototype designs or low-volume production
  • [0239]
    Another technology where the direct-write deposition of electronic features according to the present invention provides significant advantages is for flat panel displays, such as plasma display panels. Ink-jet deposition of metal powders is a particularly usefuil method for forming the electrodes for a plasma display panel. The nanoparticle compositions and methods according to the present invention can advantageously be used to form the electrodes, as well as the bus lines and barrier ribs, for the plasma display panel. Typically, a metal paste is printed onto a glass substrate and is fired in air at from about 450° C. to about 600° C. Direct-write deposition of metal nanoparticle compositions offers many advantages over paste techniques including faster production time and the flexibility to produce prototypes and low-volume production applications. The deposited features will have high resolution and dimensional stability, and will have a high density.
  • [0240]
    Another type of flat panel display is a field emission display (FED). The compositions and methods of the present invention can advantageously be used to deposit the microtip emitters of such a display. More specifically, a direct-write deposition process such as an ink-jet deposition process can be used to accurately and uniformly create the microtip emitters on the backside of the display panel.
  • [0241]
    The present invention is also applicable to inductor-based devices including transformers, power converters and phase shifters. Examples of such devices are illustrated in, e.g., U.S. Pat. Nos. 5,312,674; 5,604,673 and 5,828,271, the entire disclosures whereof are incorporated by reference herein. In such devices, the inductor is commonly formed as a spiral coil of an electrically conductive trace, typically using a thick-film paste method. To provide the most advantageous properties, the metallized layer, which is typically silver, must have a fine pitch (line spacing). The output current can be greatly increased by decreasing the line width and decreasing the distance between lines. The direct-write process of the present invention is particularly advantageous for forming such devices, particularly when used in a low-temperature co-fired ceramic package (LTCC).
  • [0242]
    The present invention can also be used to fabricate antennas such as antennas used for cellular telephones. The design of antennas typically involves many trial and error iterations to arrive at the optimum design. The direct-write process of the present invention advantageously permits the formation of antenna prototypes in a rapid and efficient manner, thereby reducing a product development time. Examples of microstrip antennas are illustrated in, e.g., U.S. Pat. Nos. 5,121,127; 5,444,453; 5,767,810 and 5,781,158, the entire disclosures whereof are incorporated herein by reference. The methodology of the present invention can be used to form the conductors of an antenna assembly.
  • [0243]
    Additional applications of the metal nanoparticle compositions and methods of the present invention include low cost or disposable electronic devices such as electronic displays, electrochromic, electrophoretic and light-emitting polymer-based displays. Other applications include circuits embedded in a wide variety of devices such as low cost or disposable light-emitting diodes, solar cells, portable computers, pagers, cell phones and a wide variety of internet compatible devices such as personal organizers and web-enabled cellular phones.
  • [0244]
    The compositions and methods of the present invention can also produce conductive patterns that can be used in flat panel displays. The conductive materials used for electrodes in display devices have traditionally been manufactured by commercial deposition processes such as etching, evaporation, and sputtering onto a substrate. In electronic displays it is often necessary to utilize a transparent electrode to ensure that the display images can be viewed. Indium tin oxide (ITO), deposited by means of vacuum-deposition or a sputtering process, has found widespread acceptance for this application. For rear electrodes (i.e., the electrodes other than those through which the display is viewed) it is often not necessary to utilize transparent conductors. Rear electrodes can therefore be formed from conventional materials and by conventional processes. Again, the rear electrodes have traditionally been formed using costly sputtering or vacuum deposition methods. The compositions according to the present invention allow the direct deposition of metal electrodes onto low temperature substrates such as plastics. For example, a silver metal nanoparticle composition can be ink-jet printed and heated at 150° C. to form 150 μm by 150 μm square electrodes with good adhesion and sheet resistivity values.
  • [0245]
    In one aspect, the metal nanoparticle compositions of the present invention may be used to interconnect electrical elements on a substrate, such as non-linear elements. Non-linear elements are defined herein as electronic devices that exhibit nonlinear responses in relationship to a stimulus. For example, a diode is known to exhibit a nonlinear output-current/input-voltage response. An electroluminescent pixel is known to exhibit a non-linear light-output/applied-voltage response. Nonlinear devices also include, but are not limited to, transistors such as TFTs and organic field effect transistors (OFETs), emissive pixels such as electroluminescent pixels, plasma display pixels, field emission display (FED) pixels and organic light emitting device (OLED) pixels, non emissive pixels such as reflective pixels including electrochromic material, rotatable microencapsulated microspheres, liquid crystals, photovoltaic elements, and a wide range of sensors such as humidity sensors.
  • [0246]
    Nonlinear elements, which facilitate matrix addressing, are an essential part of many display systems. For a display of MxN pixels, it is desirable to use a multiplexed addressing scheme whereby M column electrodes and N row electrodes are patterned orthogonally with respect to each other. Such a scheme requires only M+N address lines (as opposed to M×N lines for a direct-address system requiring a separate address line for each pixel). The use of matrix addressing results in significant savings in terms of power consumption and cost of manufacture. As a practical matter, the feasibility of using matrix addressing usually hinges upon the presence of a nonlinearity in an associated device. The nonlinearity eliminates crosstalk between electrodes and provides a thresholding function. A traditional way of introducing nonlinearity into displays has been to use a backplane having devices that exhibit a nonlinear current/voltage relationship. Examples of such devices include thin-film transistors (TFT) and metal-insulator-metal (MIM) diodes. While these devices achieve the desired result, they involve thin-film processes, which suffer from high production costs as well as relatively poor manufacturing yields.
  • [0247]
    The present invention allows the direct printing of the conductive components of nonlinear devices including the source, the drain and the gate. These nonlinear devices may include directly printed organic materials such as OFET or organic thin film transistors (OTFT), directly printed inorganic materials and hybrid organic/inorganic devices such as a polymer based field effect transistor with an inorganic gate dielectric. Direct printing of these conductive materials will enable low cost manufacturing of large area flat displays.
  • [0248]
    The compositions and methods of the present invention are capable of producing conductive patterns that can be used in flat panel displays to form, e.g., the address lines or data lines. The present invention provides ways to form address and data lines using deposition tools such as an ink-jet device. The metal nanoparticle compositions of the present invention allow printing on large area flexible substrates such as plastic substrates and paper substrates, which are particularly useful for large area flexible displays. Address lines may additionally be insulated with an appropriate insulator such as a non-conducting polymer or other suitable insulator. Alternatively, an appropriate insulator may be formed so that there is electrical isolation between row conducting lines, between row and column address lines, between column address lines or for other purposes. By way of non-limiting example, these lines can be printed with a thickness of, e.g., about one μm and a line width of about 100 μm by ink-jet printing the metal nanoparticle composition. These data lines can be printed continuously on large substrates with an uninterrupted length of several meters. Surface modification can be employed, as is discussed above, to confine the composition and to enable printing of lines as narrow as about 10 μm. The deposited lines can be heated to about 200° C. to form metal lines with a bulk conductivity that is not less than about 10 percent of the conductivity of the equivalent pure metal.
  • [0249]
    Flat panel displays may incorporate emissive or reflective pixels. Some examples of emissive pixels include electroluminescent pixels, photoluminescent pixels such as plasma display pixels, field emission display (FED) pixels and organic light emitting device (OLED) pixels. Reflective pixels include contrast media that can be altered using an electric field. Contrast media may be electrochromic material, rotatable microencapsulated microspheres, polymer dispersed liquid crystals (PDLCs), polymer stabilized liquid crystals, surface stabilized liquid crystals, smectic liquid crystals, ferroelectric material, or other contrast media well known in art. Many of these contrast media utilize particle-based non-emissive systems. Examples of particle-based non-emissive systems include encapsulated electrophoretic displays (in which particles migrate within a dielectric fluid under the influence of an electric field); electrically or magnetically driven rotating-ball displays as disclosed in, e.g., U.S. Pat. Nos. 5,604,027 and 4,419,383, which are incorporated herein by reference in their entireties; and encapsulated displays based on micromagnetic or electrostatic particles as disclosed in, e.g., U.S. Pat. Nos. 4,211,668, 5,057,363 and 3,683,382, which are incorporated by reference herein in their entireties. A preferred particle non-emissive system is based on discrete, microencapsulated electrophoretic elements, examples of which are disclosed in U.S. Pat. No. 5,930,026 which is incorporated by reference herein in its entirety.
  • [0250]
    In another aspect, the present invention relates to the direct printing of conductive features, such as electrical interconnects and electrodes for addressable, reusable, paper-like visual displays. Examples of paper-like visual displays include “gyricon” (or twisting particle) displays and forms of electronic paper such as particulate electrophoretic displays (available from E-ink Corporation, Cambridge, Mass.). A gyricon display is an addressable display made up of optically anisotropic particles, with each particle being selectively rotatable to present a desired face to an observer. For example, a gyricon display can incorporate “balls” where each ball has two distinct hemispheres, one black and the other white. Each hemisphere has a distinct electrical characteristic (e.g., zeta potential with respect to a dielectric fluid) so that the ball is electrically as well as optically anisotropic. The balls are electrically dipolar in the presence of a dielectric fluid and are subject to rotation. A ball can be selectively rotated within its respective fluid-filled cavity by application of an electric field, so as to present either its black or white hemisphere to an observer viewing the surface of the sheet.
  • [0251]
    In a preferred aspect, a metal electrode may be printed for the purpose of charge injection into a conducting or semiconducting polymer layer. For many applications, it is preferred that this metal electrode has a work function that is matched to the work function of the polymer. In a preferred aspect, a printed Ni electrode with a work function of more that 5 eV is used to ink-jet charge carriers into a conducting polymer layer, for example a source electrode or a drain electrode layer.
  • [0252]
    In another aspect, the present invention relates to electrical interconnects and electrodes for organic light emitting displays (OLEDs). Organic light emitting displays are emissive displays consisting of a transparent substrate coated with a transparent conducting material (e.g., ITO), one or more organic layers and a cathode made by evaporating or sputtering a metal of low work function characteristics (e.g., calcium or magnesium). The organic layer materials are chosen so as to provide charge injection and transport from both electrodes into the electroluminescent organic layer (EL), where the charges recombine to emit light. There may be one or more organic hole transport layers (HTL) between the transparent conducting material and the EL, as well as one or more electron injection and transporting layers between the cathode and the EL. The metal nanoparticle compositions according to the present invention allow the direct deposition of metal electrodes onto low temperature substrates such as flexible large area plastic substrates that are particularly preferred for OLEDs. For example, a metal nanoparticle composition of the present invention may be ink-jet printed and heated at 150° C. to form a 150 μm by 150 μm square electrode with good adhesion and a sheet resistivity. The compositions and printing methods of the present invention also enable printing of row and column address lines for OLEDs. These lines can be printed with a thickness of about one μm and a line width of about 100 μm using ink-jet printing. These data lines can be printed continuously on large substrates with an uninterrupted length of several meters. Surface modification can be employed, as is discussed above, to confine the metal nanoparticle composition and to enable printing of such lines as narrow as about 10 μm. The printed ink lines can be heated to, e.g., about 150° C. and form metal lines with a bulk conductivity that is at least about 5 percent of the conductivity of the equivalent pure metal.
  • [0253]
    In a particularly preferred aspect of the present invention, an optically reflective metal anode may be ink-jet printed using a silver nanoparticle ink. The top emission anode may be printed on top of an organic layer and processed at a temperature below about 180° C. and for a period of less than 5 minutes so that the organic layer does not get damaged. A layer comprising a light-emitting polymer may be printed on top of this electrode. This emission anode may be less than about 200 micrometer wide and may be used for charge injection into said light emitting polymer. The electrode may be reflective to ensure that light generated in the OLED device stack is reflected back towards the viewer.
  • [0254]
    In another aspect, the present invention relates to electrical interconnects and electrodes for liquid crystal displays (LCDs), including passive-matrix and active-matrix. Particular examples of LCDs include twisted nematic (TN), supertwisted nematic (STN), double supertwisted nematic (DSTN), retardation film supertwisted nematic (RFSTN), ferroelectric (FLCD), guest-host (GHLCD), polymer-dispersed (PD), polymer network (PN).
  • [0255]
    Thin film transistors (TFTs) are well known in the art, and are of considerable commercial importance. Amorphous silicon-based thin film transistors are used in active matrix liquid crystal displays. One advantage of thin film transistors is that they are inexpensive to make, both in terms of the materials and the techniques used to make them. In addition to making the individual TFTs as inexpensively as possible, it is also desirable to inexpensively make the integrated circuit devices that utilize TFTs. Accordingly, inexpensive methods for fabricating integrated circuits with TFTs, such as those of the present invention, are an enabling technology for printed logic.
  • [0256]
    For many applications, conductive polymers are not adequately conductive to achieve the desired switching speeds of an integrated circuit due to high RC time constants. Printed pure metals, as enabled by the metal nanoparticle compositions of the present invention, achieve the required performance. By way of non-limiting example, a metal interconnect printed by using a silver metal nanoparticle composition as provided by the present invention may result in a reduction of the resistance (R) and an associated reduction in the time constant (RC) by a factor of about 100,000, or even by a factor of about 1,000,000, as compared to current conductive polymer interconnect materials used to connect polymer transistors.
  • [0257]
    Field-effect transistors (FETs), with organic semiconductors as active materials, are the key switching components in contemplated organic control, memory, or logic circuits, also referred to as plastic-based circuits. An expected advantage of such plastic electronics is the ability to fabricate them more easily than traditional silicon-based devices. Plastic electronics thus provide a cost advantage in cases where it is not necessary to attain the performance level and device density provided by silicon-based devices. For example, organic semiconductors are expected to be much more readily printable than vapor-deposited inorganics, and are also expected to be less sensitive to air than recently proposed solution-deposited inorganic semiconductor materials. For these reasons, there have been significant efforts expended in the area of organic semiconductor materials and devices.
  • [0258]
    Organic thin film transistors (TFTs) are expected to become key components in the plastic circuitry used in display drivers of portable computers and pagers, and memory elements of transaction cards and identification tags. A typical organic TFT circuit contains a source electrode, a drain electrode, a gate electrode, a gate dielectric, an interlayer dielectric, electrical interconnects, a substrate, and semiconductor material. The metal nanoparticle compositions of the present invention may be used to deposit several of the components of this circuit.
  • [0259]
    One of the most significant factors in bringing organic TFT circuits into commercial use is the ability to deposit all the components on a substrate quickly, easily and inexpensively as compared with silicon technology (i.e., by reel-to-reel printing). The metal nanoparticle compositions of the present invention enable the use of low cost deposition techniques, such as ink-jet printing, for depositing these components.
  • [0260]
    The metal nanoparticle compositions of the present invention are particularly useful for the direct printing of electrical connectors as well as antennae of smart tags, smart labels, and a wide range of identification devices such as radio frequency identification (RFID) tags. In a broad sense, the metal nanoparticle compositions can be utilized for electrical connection of semiconductor radio frequency transceiver devices to antenna structures and particularly to radio frequency identification device assemblies. A radio frequency identification device (“RFID”) by definition is an automatic identification and data capture system comprising readers and tags. Data is transferred using electric fields or modulated inductive or radiating electromagnetic carriers. RFID devices are becoming more prevalent in such configurations as, for example, smart cards, smart labels, security badges, and livestock tags.
  • [0261]
    The present invention also comprises a wide variety of security and authentication applications. For example, with the advent and growth of desktop publishing and color-photocopiers, the opportunities for document and coupon fraud have increased dramatically. The present invention has utility in a variety of areas including coupon redemption, inventory security, currency security, compact disk security and driver's license and passport security. The present invention can also be utilized as an effective alternative to magnetic strips. Presently, magnetic strips include identification numbers such as credit card numbers that are programmed at the manufacturer. These strips are prone to failure and are subject to fraud because they are easily copied or modified. To overcome these shortcomings, circuits can be printed on the substrate and encoded with specific consumer inforrnation. Thus, the present invention can be used to improve the security of credit cards, ATM cards and any other tracking card, which uses magnetic strips as a security measure.
  • [0262]
    In another security application aspect of the present invention, metallic features can be printed on various articles to produce overt security features. For example, such features are useful in applications that provide security to currency (e.g. bank notes) or brand protection to branded goods. By way of non-limiting example, a unique metallic, reflective feature may be digitally printed on a surface to provide an easily recognizable and reflective metallic feature. The combination of the reflective, metallic nature of the feature and the digital nature of the information printed by, e.g., ink-jet printing, can provide multiple levels of security to the substrate. The security provided by such features may be further enhanced by combining the printed metallic feature with other security features such optically variable features, embossing, watermarks, holograms, as well as with other features of the metallic ink itself such as electrical conductivity and magnetism.
  • [0263]
    By way of non-limiting example, a metallic nanoparticle composition according to the present invention can be printed in such a way as to produce a semi-transparent feature in the visible region of the electromagnetic spectrum. The semi-transparency of this feature enables multiple security features to be combined in unique combinations, one being visible through the other. The extent of optical semi-transparency compared to reflectivity of this feature can be adjusted according to the layer characteristics and the processing conditions. By way of example, a reflective semi-transparent feature can be printed over the surface of other overt features such as color images, watermarks, holograms and the like, or combined with covert features such as, e.g., luminsecent materials such as UV or anti-stokes phosphors as well as other covert features. The semi-transparent coating may also optionally be electroncially conductive or magnetic adding an additional level of covert security to these features. A semi-transparent coating can also be created in a way that results in selective transparency in other regions of the electromagnetic spectrum such as, e.g., the ultraviolet and infrared regions.
  • [0264]
    In another non-limiting aspect, layers comprising different nanoparticle compositions of the present invention may be printed to achieve selective transparancy according to the physical characteristics of the nanoparticle metals that are printed. For example, by printing two different nanoparticle inks over a color feature, optical transparency of a specific color may be achieved.
  • [0265]
    A semi-transparent metal nanoparticle coating according to the present invention may be achieved by a number of different methods. By way of non-limiting example, the digital resolution of a feature that is printed can be reduced to reduce the quantity of material printed on a substrate surface, resulting in an increase of the optical transparency by reducing the amount of surface area that is covered. For example, the nanoparticle ink can be diluted to reduce the metal nanoparticle content and printed to result in a thinner layer that fully covers the surface.
  • [0266]
    The curing process of the deposited (printed) nanoparticle composition of the present invention may also have a strong influence on the level of transparency compared to its reflectivity. Usually a higher loading of metal nanoparticles, a higher curing temperature and a longer curing time will all contribute to higher reflectivity and lower optical transparency of printed feature. A lower curing temperature will usually lead to lower reflectivity, but increased transparency. Optimum conditions for achieving a combination of increased optical transparency and increased reflectivity usually include thinner layers of complete coverage of nanoparticles cured to give a more continuous film.
  • [0267]
    In another security application aspect of the present invention, the metal nanoparticle composition (ink) may contain a coloring pigment and/or a dye such that when the ink is printed and cured, the feature has a metallic luster and in addition is of a color that is not characteristic of the metal itself. By way of non-limiting example, a gold luster may be achieved by mixing a yellow dye with a silver nanoparticle ink. In a further aspect, a fluorescent or phosphorescent additive may be incorporated in the metal nanoparticle composition of the present invention, in which case a feature produced therefrom may have a combination of properties that include metallic luster (an overt feature) and luminescence (a covert feature) which can be detected by exposure to electromagnetic radiation of suitable wavelength, for example, by UV light of short (e.g., about 254 nm) or long (e.g., about 365 nm) wavelengths. In a further aspect, the pigment or dye may also be luminescent, resulting in a combination of characteristics where the printed metallic feature has a metallic luster, the color of which (in ordinary light) is determined by the nature of the pigment or dye, but under irradiation with, e.g., UV light, a visible light emission is observed.
  • [0268]
    In another security application aspect, the metal nanoparticle composition of the present invention may be printed onto a substrate that is subsequently used to produce security threads. In this embodiment, the composition may be printed onto, for example, paper or an organic polymer substrate together with a number of additional security features. The additional use of digital printing assists in providing variable information that creates an additional barrier to counterfeiting of the article. In a typical application, the thread may be used to provide an added level of security to bank notes.
  • [0269]
    In yet another security application aspect of the present invention, a printed metallic feature may be used as part of a security feature that has unique optical characteristics such as an optically variable feature. By way of non-limiting example, the metal nanoparticle composition of the present invention may be used to print a metallic feature in a certain pattern that is highly reflective after curing. This reflective metallic feature can be used as the base layer in a series of printed layers to create an optical feature. A second layer can be added over the surface of the reflective metallic layer, the second layer being optically transparent. A non-limiting example of the second layer is a magnesium fluoride layer. A third layer may then be printed over the surface of the second layer such that it has the properties of being semi-transparent and reflective with respect to visible light. A non-limiting example of this third layer is another coating of the metal nanoparticle ink that is printed and cured in a way that provides for a very thin layer. The effect created by this three layer stack (sandwich) is an optical interference pattern between the light that is reflected by the top layer (the third layer) and the base layer (the first reflective metal ink layer), resulting in a unique color as the article on which these layers are printed is tilted (changed in angle) with respect to the viewer. The optical variations that may be created by this kind of structure can be varied by the composition of the layers that comprise this structure and the thickness of the printed layers, in addition to the unique optical interference patterns created by the stack.
  • [0270]
    The material of the second, middle layer of the sandwich can be almost any material that isoptically transparent by virtue of either its inherent phyical absorption spectrum and/or by the fact that it is comprised of particles with a size in the range that reduces light scattering. The material may be inorganic organic (such as, e.g., an organic polymer) or a mixture of both. Materials with high refactive index such as, e.g., TiO2 provide for enhanced effects. The material may also have some other functional characteristics such as be comprised of luminescent particles such that the feature has a combination of overt and covert properties.
  • [0271]
    In another security application aspect of the present invention, the conductivity of a printed metal layer may provide a security feature in an article. By way of non-limiting example, a printed metallic feature may be cured under conditions that result in electrical conductivity, thus providing an additional level of security. The presence of electrical conductivity can be determined, for example, by a contact method such as, e.g., 2-point or 4-point probe measurements, or by contact-less methods in which the presence of a conductive feature is determined in an electric or magnetic field. For example, the printed metallic feature can be constructed with dimensions (thickness, width and length) in which the electrical conductivity of the feature may vary as a function of the position within the feature where the measurement is made. This provides for an additional level of security in this feature.
  • [0272]
    A printed metallic feature made from the compositions and by the methods of the present invention can be combined with other security features to create additional levels of security. The additional security features may be overt or covert. Non-limiting examples of additional overt features include optically variable features, holograms, embossing, water marks and the like. Non-limiting examples of additional covert features include luminescent materials such as UV excitable phosphors or up-conversion phosphors.
  • [0273]
    It has recently been demonstrated that silver and gold metal nanoparticles increase the emission characteristics of luminescent materials by acting as a sensitizer or “antenna”. A metal nanoparticle composition of the present invention printed over the surface of a phosphor powder layer may improve the luminescence characteristics of that layer to achieve luminescent characteristics that are unique in terms of brightness and emission spectral features for that combination of materials. By way of non-limiting example, gold nanoparticles in combination with Gd2O3:Tb phosphor particles lead to enhanced emission. The same applies to silver nanoparticles in combination with Eu3+ doped glasses.
  • [0274]
    The metal nanoparticle compositions of the present invention also enable the low cost, high volume, highly customizable production of electronic labels. Such labels can be formed in various sizes and shapes for collecting, processing, displaying and/or transmitting information related to an item in human or machine readable form. The metal nanoparticle compositions of the present invention can be used to print the conductive features required for forming, e.g., the logic circuits, electronic interconnections and antennae in electronic labels. The electronic labels can be an integral part of a larger printed item such as a lottery ticket structure with circuit elements disclosed in a pattern as disclosed in U.S. Pat. No. 5,599,046, the entire disclosure whereof is incorporated by reference herein.
  • [0275]
    In another aspect of the present invention, the conductive patterns made in accordance with the present invention can be used as electronic circuits for making photovoltaic panels. Screen-printing is conventionally used in mass scale production of solar cells. Typically, the top contact pattern of a solar cell consists of a set of parallel narrow finger lines and wide collector lines deposited essentially at a right angle to the finger lines on a semiconductor substrate or wafer. Such front contact formation of crystalline solar cells is performed with standard screen-printing techniques. Direct printing of these contacts with the metal nanoparticle compositions of the present invention provides the advantages of production simplicity, automation, and low production cost.
  • [0276]
    Low series resistance and low metal coverage (low front surface shadowing) are basic requirements for the front surface metallization in solar cells. Minimum metallization widths of about 100 to about 150 μm are obtained using conventional screen-printing. This causes a relatively high shading of the front solar cell surface. In order to decrease the shading, a large distance between the contact lines, i.e., 2 to 3 mm is required. On the other hand, this implies the use of a highly doped, conductive emitter layer. However, the heavy emitter doping induces a poor response to short wavelength light. Narrower conductive lines may be printed using the metal nanoparticle compositions and printing methods of the present invention. The metal nanoparticle compositions of the present invention may enable direct printing of finer features down to about 50 μm. The metal nanoparticle compositions of the present invention further may enable the printing of pure metals with resistivity values of the printed features as low as 2 times the bulk resistivity after processing at temperatures as low as about 200° C.
  • [0277]
    The low processing and direct-write deposition capabilities according to the present invention are suitable also for large area solar cell manufacturing on organic and flexible substrates. This is particularly usefuil in manufacturing novel solar cell technologies based on organic photovoltaic materials such as organic semiconductors and dye sensitized solar cell technology as disclosed in U.S. Pat. No. 5,463,057, the entire disclosure whereof is incorporated by reference herein. The metal nanoparticle compositions according to the present invention can be directly printed and heated to yield a bulk conductivity that may be no less than about 10 percent of the conductivity of the equivalent pure metal, and achieved by heating the printed features at temperatures below about 200° C. on polymer substrates such as plexiglass (PMMA).
  • [0278]
    Another aspect of the present invention comprises the production of an electronic circuit for making printed wiring board (PWBs) and printed circuit boards (PCBs). In conventional subtractive processes used to make printed-wiring boards, wiring patterns are formed by preparing pattern films. The pattern films are prepared by means of a laser plotter in accordance with wiring pattern data outputted from a CAD (computer-aided design system), and are etched on copper foil by using a resist ink or a dry film resist. In such conventional processes, it is necessary to first form a pattern film, and to prepare a printing plate in the case when a photo-resist ink is used, or to take the steps of lamination, exposure and development in the case when a dry film resist is used.
  • [0279]
    Such methods can be said to be methods in which the digitized wiring data are returned to an analog image-forming step. Screen-printing has a limited work size because of the printing precision of the printing plate. The dry film process is a photographic process and, although it provides high precision, it requires many steps, resulting in a high cost especially for the manufacture of small lots.
  • [0280]
    The metal nanoparticle compositions and methods of the present invention offer solutions to overcome the limitations of the current PWB formation process. For example, they do not generate any waste. The methods of the present invention may be a single step direct printing process and are compatible with small-batch and rapid turn around production runs. For example, a copper nanoparticle composition can be directly printed onto FR4 (an epoxy resin impregnated fiberglass) to form interconnection circuitry. These features are formed by heating printed copper nanoparticles in an N2 ambient at about 150° C. to form copper lines with a line width of not greater than about 100 μm, a line thickness of not greater than about 5 μm, and a bulk conductivity that is at least about 10 percent of the conductivity of the pure copper metal.
  • [0281]
    In another non-limiting example, Ag may be ink-jet printed on a PCB (printed circuit board) and used as a seed layer for Cu electroplating or electroless deposition of Cu. Ag may also be used to ink-jet print electrodes for embedded passives for PCBs.
  • [0282]
    Patterned electrodes obtained by one aspect of the present invention can also be used for screening electromagnetic radiation or earthing electric charges, in making touch screens, radio frequency identification tags, electrochromic windows and in imaging systems, e.g., silver halide photography or electrophotography. A device such as the electronic book described in U.S. Pat. No. 6,124,851, the entire disclosure whereof is incorporated by reference herein, can also be formed using the compositions of the present invention.
  • [0283]
    In addition, metal nanoparticles (e.g., silver nanoparticles) having a size of less than about 100 nm have outstanding optical characteristics in that they are perfectly reflective, i.e., do not diffract incident light, resulting in a perfect mirror finish on articles onto which they are applied. This is a valuable property for, e.g., graphic and mirror applications.
  • [0284]
    The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.
  • [0285]
    The present invention is further illustrated with reference to an exemplary embodiment thereof wherein silver is the metal of the nanoparticles and polyvinylpyrrolidone is the anti-agglomeration substance.
  • EXAMPLE 1 Preparation of Silver Nanoparticles Carrying PVP Thereon
  • [0286]
    In a mixing tank a solution of 1000 g of PVP (M.W. 10,000, Aldrich) in 2.5 L of ethylene glycol is prepared and heated to 120° C. In a second mixing tank, 125 g of silver nitrate is dissolved in 500 ml of ethylene glycol at 25° C. These two solutions are rapidly combined (within about 5 seconds) in a reactor, in which the combined solutions (immediately after combination at a temperature of about 114° C.) are stirred at 120° C. for about 1 hour. The resultant reaction mixture is allowed to cool to room temperature and about 0.25 L of ethylene glycol is added thereto to replace evaporated ethylene glycol. This mixture is stirred at high speed for about 30 minutes to resuspend any particles that have settled during the reaction. The resultant mixture is transferred to a mixing tank where 12 L of acetone and about 1 L of ethylene glycol are added. The resultant mixture is stirred thoroughly and then transferred to a centrifuge where it is centrifuged for about 20 minutes at 1,500 g to separate the silver nanoparticles from the liquid phase. This affords 70 g of nanoparticles which have PVP adsorbed thereon. The particles are subsequently suspended in 2,000 ml of ethanol to remove, inter alia, excess PVP, i.e., PVP that is not adsorbed on the nanoparticles but is present merely as a contaminant. At this point, the ethanol suspension of particles is preferably filtered through a 1.5 μm nylon filter, thus filtering out particles that are larger than 1.5 μm. The filtrate is subsequently centrifuged and the resulting cake is dried in a vacuum oven at about 35° C. and about 10-2 torr to afford dry nanoparticles. These nanoparticles exhibit a PVP content of about 4 to about 8 weight percent, depending on the time the nanoparticles have been in contact with the ethanol.
  • [0287]
    Alternatively, the ethanol suspension may be centrifuged without first filtering through a 1.5 μm nylon filter. The resultant filter cake of nanoparticles is dried in a vacuum oven at about 35° C. and about 10−2 torr to afford dry nanoparticles. These nanoparticles, like the particles obtained after filtering through a 1.5 μm filter, exhibit a PVP content of about 4 to about 8 weight percent, depending on the time the nanoparticles have been in contact with the ethanol.
  • [0288]
    ICP (inductively coupled plasma) data indicates that the longer the particles are in contact with the ethanol, the more of the acetone and ethylene glycol present in the PVP matrix is displaced by ethanol, resulting in particles with an increasingly higher silver content.
  • [0289]
    It is believed that several characteristics of the reagents that are used in the process described above may ultimately affect the particle size distribution (PSD) of the nanoparticles produced by the process. At least four such characteristics are the water content of the PVP, the 2-pyrrolidone content of the PVP (PVP inherently contains 2-pyrrolidone), the formic acid content of the PVP and the water content of the ethylene glycol used.
  • [0290]
    Although the reasons are not entirely clear at this time, it has been observed that the water content of the PVP may have an effect on the PSD of the nanoparticles produced by the process described above. PVP is a hygroscopic substance that typically has a residual amount of water contained therein. In some cases, the presence of water in the PVP leads to the production of nanoparticles with a desirable PSD. In other cases, however, when the water content in the PVP is reduced, the same result is observed. Thus, it is not entirely clear if it is preferable to have PVP where the water content has been reduced or PVP where the residual water content is not reduced. In one embodiment, the water content of the PVP is about 1-10% by weight, or about 1-8% by weight, or about 2-10% by weight or preferably about 2-7% by weight. The water content of the PVP may be reduced by heating the PVP at about 70-80° C. overnight (e.g., 8-14 hours). The PVP may optionally be stirred while it is heated. In addition, the heating may be optionally performed under an inert atmosphere (e.g., argon and nitrogen) or in vacuo.
  • [0291]
    Although the reasons are not entirely clear at this time, it has also been observed that the presence of 2-pyrrolidone in the PVP may have an effect on the PSD of the nanoparticles produced by the process described above. 2-pyrrolidone is a contaminant comprised in the PVP that results from the synthesis of PVP. In one embodiment, the 2-pyrrolidone content of the PVP is about 1-10% by weight, or about 1-8% by weight, or about 1-5% by weight or preferably about 5% by weight.
  • [0292]
    In addition, although the reasons are not entirely clear at this time, it has also been observed that the presence of formic acid in the PVP may have an effect on the PSD of the nanoparticles produced by the process described above. Formic acid is a contaminant that may be comprised in the PVP that results from the synthesis of PVP. In some cases, the presence of formic acid in the PVP leads to the production of nanoparticles with a desirable PSD. In other cases, however, when the formic acid content in the PVP is reduced, the same result is observed. Thus, it is not clear if it is preferable to have PVP where the formic acid content has been reduced or PVP where the formic acid content is not reduced. In one embodiment, the formic acid content of the PVP is about 0-2% by weight, or about 0-1% by weight, or about 0-0.8% by weight or preferably about 0.3% by weight. The formic acid content of the PVP may be reduced by heating the PVP at about 70-80° C. overnight (e.g., 8-14 hours). The PVP may optionally be stirred while it is heated. In addition, the heating may be optionally performed under an inert atmosphere (e.g., argon and nitrogen) or in vacuo.
  • [0293]
    Finally, although the reasons are not entirely clear at this time, it has also been observed that the presence of water in the ethylene glycol may have an effect on the PSD of the nanoparticles produced by the process described above. It is possible that some water must be present in the ethylene glycol in order to produce nanoparticles with a desirable PSD. Without being bound by any particular theory, it is possible that the presence of water content in ethylene glycol influences the equilibrium between ethylene glycol and its decomposition product, acetaldehyde, according to the reaction shown below:
    Figure US20060189113A1-20060824-C00001
  • [0294]
    Even though it is possible that it is produced in an extremely small quantity (i.e., the equilibrium favors ethylene glycol), the acetaldehyde produced, in turn, acts as a reducing agent for the silver nitrate, thereby effecting the reduction of silver ions in silver nitrate to silver metal. The silver metal, in turn, can precipitate out of the ethylene glycol solution prior to mixing the silver nitrate/ethylene glycol solution with the PVP/ethylene glycol solution. It is possible that the precipitation of silver metal in the silver nitrate/ethylene glycol solution, prior to mixing with the PVP/ethylene glycol solution, could lead to the production of nanoparticles once the solutions are mixed, where the nanoparticles have an undesirable PSD (e.g., a polydisperse powder fraction with an increased amount of large particles and agglomerates). In one embodiment, the water content of the ethylene glycol is about 0.01-0.10% by weight, or about 0.01-0.05% by weight, or about 0.01-0.04% by weight or preferably about 0.04% by weight.
  • EXAMPLE 2 Effect of PVP Molecular Weight on Resistivity and Curing Temperature
  • [0295]
    Silver nanoparticles can be synthesized using 58,000 g/mol PVP using a process substantially the same as the process used to synthesize silver nanoparticles using 10,000 g/mol PVP by mixing a PVP/ethylene glycol solution with a silver nitrate/ethylene glycol solution. Once the reaction is complete, 250 mL of ethylene glycol is mixed into the reaction solution after cooling down. The resulting solution is equally divided into five 4-L Nalgene® bottles. 200 mL of ethylene glycol and 3 L of acetone are added to each plastic bottle. The bottles are sealed with lids and shaken up to create a black precipitate suspension in the solvent mixture. The suspensions are transferred to centrifuge bottles and centrifuged at 2,200 RPM for 10 minutes. The clear, light orange supernatants are discarded to leave behind a reflective, silver cake. More black suspension is added to the same bottles and the separation steps are repeated until all of the silver nanoparticles are caked in the bottom of the centrifuge bottles. 600 mL of ethanol are added to each centrifuge bottle to remove, inter alia, excess PVP. At this point, the ethanol suspension of particles is preferably filtered through a 1.5 μm nylon filter, thus filtering out particles that are larger than 1.5 μm. The filtrate is subsequently centrifuged and the resulting cake is dried in vacuo for 2-3 hours.
  • [0296]
    Alternatively, the ethanol suspension may be centrifuged without filtering through a 1.5 μm nylon filter. In this case, the bottles are centrifuged at 2,200 RPM overnight, and the clear, dark orange supernatants are discarded to leave behind a highly reflective, bluish-silver cake. The silver nanoparticles are then dried in vacuo for 2-3 hours to form gold-colored granules.
  • [0297]
    Silver nanoparticle inks are spin coated onto glass and tested to ascertain the electrical properties. Liquid crystal display (LCD) glass slides are cut into 2″ squares and given 5 minutes of UV-Ozone treatment. This is followed by wiping the slides with a lint-free cloth wetted with acetone and then another lint-free cloth wetted by denatured ethanol. In succession, each slide is secured to a 2″ vacuum chuck on the spin coater. The slide is spun at 500 RPM for 10 seconds while 0.8 mL of silver ink is dispensed using a micropipette, after which the slide is spun at 1,000 RPM for 20 seconds. After spin coating, slides are placed in a pre-heated Despatch oven set to either 100 or 120° C. for 60 minutes to cure the silver ink films. Then the silver-coated slides are removed and allowed to cool. Each slide is placed on the four-point probe station, and five resistance measurements are taken near the center of the silver films. After the measurements are taken, a 1-2 mm wide, 0.5-1 cm long scratch is made in the center of each film using a stainless steel scalpel. When making the scratch, enough pressure is applied to remove the ink layer but not enough to significantly scratch the glass substrate. Then the layer thickness is measured across five locations along the scratch, using the scratch as a reference, on the Zygo profilometer. Finally, the resistance and thickness measurements are used to calculate the resistivity for each silver film.
  • [0298]
    The electrical testing of six silver inks formulated from different silver nanoparticles made with the 10,000 g/mol PVP it was observed that the average resistivity of the samples cured at 100° C. is 101× bulk silver over a range of 22.1-234× bulk silver. For curing at 120° C., the average resistivity of the samples is 17.8× bulk silver over a range of 14.3-24.2× bulk silver. Unexpectedly, for the ink sample made with silver nanoparticles formed in the presence of 58,000 g/mol PVP, the average resistivity is 12.8× bulk silver when cured at 100° C. and 7.20× bulk silver when cured at 120° C. It is evident from the data given above that, relative to inks that employ 10,000 g/mol PVP, the ink that employs 58,000 g/mol PVP results in superior electrical performance at a relatively low curing temperature. The ability of achieving such superior electrical performance at relatively low curing temperatures with inks comprising 58,000 g/mol PVP facilitates printing such inks on flexible substrates.
  • EXAMPLE 3 Preparation and Testing of Composition for Ink-Jet Printing
  • [0299]
    Silver nanoparticles prepared according to the process described in Example 1 (ranging from about 30 nm to about 50 nm in size) are suspended in a solvent mixture composed of, in weight percent based on the total weight of the solvent mixture, 40% of ethylene glycol, 35% of ethanol and 25% of glycerol to produce an ink for ink-jet printing. The concentration of the silver particles in the ink is 20% by weight.
  • [0300]
    The ink had the following properties:
    Viscosity* (22° C.) 14.4 cP
    Surface tension** (25° C.) 31 dynes/cm
    Density 1.24 g/cc

    *measured at 100 rpm with a Brookfield DVII+ viscometer (spindle no. 18)

    **measured with a KSV Sigma 703 digital tensiometer with a standard Du Nouy ring method
  • [0301]
    The ink is chemically stable for 6 months, some sedimentation occurring after 7 days at room temperature.
  • [0302]
    Printing and Properties of Printed Features
  • [0303]
    A Spectra SE 128 head (a commercial piezo ink-jet head) is loaded with the ink of Example 3 and the following optimized printing parameters are established:
    Optimized Jetting Parameters (at 22-23° C.):
    Pulse Voltage 120 Volts
    Pulse Frequency 500 Hz (for up to one 1 hour
    of continuous operation)
    Pulse Rise Time 2.5 μs
    Pulse Width 12.0 μs
    Pulse Fall Time 2.5 μs
    Meniscus Vacuum 3.0 inches of water
    Performance Summary:
    Drop Size 39 μm (calculated volume 31 pL)
    Drop Velocity 0.33 m/s
    Spot Size (average) 70 μm (on Kapton ®; measured
    using optical microscope)
  • [0304]
    The deposited ink can be rendered conductive after curing in air at temperatures as low as 100° C. The ink exhibits a high metal yield, allowing single pass printing.
  • [0305]
    Using the above optimized jetting parameters, the ink of Example 3 is deposited in a single pass with a Spectra SE 128 head on a Kapton® substrate and on a glass substrate to print a line. The line has a maximum width of about 140 μm (Kaptong) and about 160 μm (glass) and a parabolic cross-section. The thickness of the line at the edges averages about 275 nm (Kapton®) and about 240 nm (glass) and the maximum height of the line is about 390 nm (Kapton® and glass). The differences between Kapton® and glass reflect the different wetting behavior of the ink on these two types of substrate materials.
  • [0306]
    Single pass printing with the ink of Example 3 affords a sheet resistivity of from about 0.1 to about 0.5 Ω/sq. The printed material shows a bulk resistivity in the fully sintered state of from about 4 to about 5 μΩ·cm (about 2.5-3 times the bulk resistivity of silver).
  • [0307]
    The polymer (polyvinylpyrrolidone (PVP)) on the surface of the silver nanoparticles allows the sintering of a deposited ink at very low temperatures, e.g., in the range of from about 100° C. to about 150° C. The PVP does not volatilize or significantly decompose at these low temperatures. Without wishing to be bound by any theory, it is believed that at these low temperatures the polymer moves out of the way, allowing the cores of the nanoparticles to come into direct contact and sinter together (necking). In comparison to its anti-agglomeration effect in the printing ink prior to printing, the polymer in the deposited and heat-treated ink assumes a new function, i.e., it promotes the adhesion of the printed material to a range of polymeric substrates such as, e.g., FR4 (fiberglass-epoxy resin) and Mylar® (polyethylene terephthalate) and provides structural strength. As a result of the low-temperature sintering mechanism a continuous percolation network is formed that provides continuous channels for the conduction of electrons to flow throughout the material without obstacles. This is fundamentally different from the traditional polymer thick film approach, where electrical conductivity is established during thermal curing as a result of polymer matrix shrinkage, inducing compressive stress on the flake particles and causing a reduction in their large contact resistance.
  • [0308]
    When higher-temperature sintering is performed (at about 300° C. to about 550° C.), the polymer volatilizes. As a result, sintering will occur and in comparison to low-temperature sintering a much denser metal material is formed. This leads to a better conductivity (close to the conductivity of the bulk metal), better adhesion to substrates such as glass, and better structural integrity and/or scratch resistance.
  • [0309]
    In the low temperature sintering range (from about 100° C. to about 150° C.), the present ink can advantageously be employed for applications such as, e.g., printed RF ID antennas and tags, digitally printed circuit boards, smart packages, “disposable electronics” printed on plastics or paper stock, etc. In the medium temperature range (from about 150° C. to about 300° C.) the ink may, for example, be used for printing interconnects for applications in printed logic and printed active matrix backpanes for applications such as polymer electronics, OLED displays, AMLCD technology, etc. In the high temperature range (from about 300° C. to about 550° C.) its good performance and adhesion to glass make it usefuil for printed display applications such as, e.g., plasma display panels.
  • [0310]
    Electric Performance
  • [0311]
    After the ink is printed on the substrate, it needs to be treated thermally and/or by irradiation to yield the desired electrical performance, adhesion and abrasion resistance. This treatment can be accomplished in a variety of ways such as hot plate, convection oven, infrared radiation, laser radiation, UV exposure, etc.
  • [0312]
    As a general rule, the resistivity of a printed feature will drop with curing temperature and curing time. The detailed time-temperature profile may also play a role. For example, drying the ink at a temperature of not higher than about 80° C., e.g., not higher than about 70° C., or not higher than about 60° C. before heating it to a temperature of at least about 100° C., e.g., at least about 110° C., or at least about 120° C. may result in a feature with lower conductivity than that of a line that was immediately heated to a temperature of at least about 100° C., e.g., at least about 110° C., or at least about 120° C. without allowing it to dry first.
  • [0313]
    The peak curing temperature and the curing time are main factors that determine the ultimate performance of a feature made from an ink of the present invention. In addition, secondary parameters such as heating profile (ramp rate, drying prior to curing), substrate type (coated paper, PET, glass etc.), curing ambient and heating method (oven, laser, IR etc.) may also play a role.
  • [0314]
    In one experiment, a line was printed on a Kapton® substrate using the ink of Example 3 under ambient conditions and then immediately transferred to an oven at a predetermined temperature without drying the ink. At oven temperatures above about 200° C. high conductivity could be achieved after very short curing times. For example, a 60 second cure at an oven temperature of 300° C. yielded a printed silver line exhibiting a bulk resistivity of 3.8 μΩ cm. After 60 seconds at 250° C. and after about 15 minutes at 200° C. the resistivity was about 10 μΩ cm. After about 60 minutes at 150° C. a resistivity of about 13 μΩ cm was obtained and remained substantially constant thereafter. From an extrapolation of the obtained data it is expected that in the temperature range from about 350° C. to about 400° C. a full curing can be accomplished in less than 10 seconds, which will enable curing processes such as in-line RTP (rapid thermal processing), and the associated reduction in tact time in a manufacturing process.
  • [0315]
    In this regard, it is to be noted that using the bulk resistivity value of a printed silver conductor and comparing it to the bulk resistivity of a fully dense silver object of the same geometry (length, width and layer thickness) does not usually provide a reliable indication of the actual conductivity of the printed metal. This applies particularly to low curing temperatures (e.g., below about 150° C.). In these cases, the final deposit has a significant amount of residual porosity and contains a significant amount of polymer. For example, the actual metal content may be less than 50 weight percent. Conductivity in these materials is accomplished through necking of the Ag particles which results in an efficient percolation network. It is therefore more straightforward to compare the sheet resistivities (expressed as Ω/sq) of a printed feature and a fully dense feature that has the same silver content per unit area as the printed feature.
  • [0316]
    Adhesion to the Substrate
  • [0317]
    The silver nanoparticles of the composition of Example 3 carry polymer (PVP) on the surfaces thereof. This polymer may provide improved structural integrity of a printed feature on a variety of substrates when curing is carried out at relatively low temperatures (e.g., at temperatures of from about 100° C. to about 250° C.). As set forth above, since at these temperatures the polymer will not volatilize/decompose, it is believed that the polymer merely rearranges to allow the metal cores of the particles to come into contact with each other and sinter together. In this case, the polymer can serve as adhesion promoter between the silver particles and the substrate. In addition, the polymer may provide additional cohesive strength between individual particles.
  • [0318]
    A stringent adhesion test according to ASTM D3359-02 was performed to evaluate the adhesion performance of the silver ink on a variety of substrates as a function of the curing temperature. In this test, adhesion is rated on a scale from 0 (poor) to 5 (good) based on the percentage of flaking from a cross-cut area. Using a sharp blade, horizontal and vertical lines are made with 1 mm spacing. Scotch adhesive tape is applied under pressure and peeled off under an angle of 180°. The results obtained were as follows:
  • [0319]
    On an FR4 substrate the adhesion was rated almost 4 in the curing temperature range of from 100° C. to 175° C.
  • [0320]
    On a Mylar® substrate the adhesion was between about 2 and 3.5 in the curing temperature range of from 100° C. to 175° C. On a Kapton® substrate the adhesion was about 1.5 at curing temperatures of 200° C. and 250° C. On an ITO substrate the adhesion was between about 1.5 and about 4.5 in the curing temperature range of from 350° C. to 550° C. On a glass substrate the adhesion was between about 1 and about 2 in the curing temperature range of from 350° C. to 550° C. An addition to the ink of bismuth nitrate in a weight ratio of Ag:Bi of about 12:1 afforded an adhesion rating on glass between about 3 and about 4 in the temperature range of from 100° C. to 550° C.
  • EXAMPLE 4 Coductivity Testing of Compositions on Various Paper Substrates
  • [0321]
    It was found that the Ag ink composition of Example 3 yields ink-jet printed lines on Epson Gloss IJ ink-jet paper that exhibit an electric resistance after annealing at 100° C. which is comparable to that of the same ink printed on Kapton and annealed at 200° C.
  • [0322]
    In one set of tests, the following experiments were carried out:
      • An aqueous silver ink was jetted onto glossy IJ photo paper (Canon), producing three groups of 4 lines; 1 set as single pass, 1 set as double pass, and 1 set as triple pass. All three sets were annealed on a hot plate set to 200° C. for 30 minutes. After the anneal, the lines were tested for electrical conductivity; all lines failed to exhibit conductivity.
      • The solvent-based Ag ink of Example 3 was printed on EPSON S041286 Gloss photo paper to produce samples for comparison testing with a commercially available Ag ink sample (Nippon Paint) printed on Cannon gloss paper (model not known). Two samples were printed, 1 coupon with a single print pass and 1 coupon with a double print pass.
        • The double pass print was annealed at 100° C. for 60 minutes.
        • The commercial Ag ink sample was cured at 100° C. for 60 minutes.
        • The single pass print was annealed at 100° C. for 110 minutes.
  • [0328]
    Both samples produced with the ink of Example 3 exhibited very good conductivity, comparable to the same silver ink, printed on Kapton, and annealed at 200° C. for 30 minutes.
  • [0329]
    The commercially available ink yielded a conductivity much worse than that of the ink samples according to the present invention.
  • [0330]
    The ink of Example 3 was printed on four different substrates: (a) Kapton HN-300, (b) Hammermill 05502-0 gloss color copy paper, (c) Canon Bubblejet Gloss Photo Paper GP-301 and (d) Epson Gloss Photo Paper for ink-jet S041286.
  • [0331]
    The results listed in the table below confirm the superior performance of the Example 3 ink/Epson paper combination.
    Cure Approx.
    Temp/ Resistivity pH of
    Ink Substrate Time (μΩ*cm)1 Substrate3
    Example 3 Kapton 200° C./  21 N/A
    30 min
    Example 3 Kapton 100° C./ 180 N/A
    60 min
    Example 3 Epson Photo Paper 100° C./  16 4-5
    60 min
    Example 3 Xerox High Gloss 100° C./ No N/A
    60 min Conductivity
    Example 3 Canon Photo Paper 100° C./ 525 6.5-7  
    60 min
    Commercial Canon Photo Paper 100° C./ 54002 6.5-7  
    60 min
    N/A HP Premium satin N/A N/A 5.0
    Gloss
    N/A HP Premium Gloss N/A N/A 5.0
    N/A Kodak Premium N/A N/A 5.5
    Gloss
    N/A Kodak Ultima N/A N/A 5.0-5.5
    N/A Canon PP101 N/A N/A 6.5
    N/A Canon PR101 N/A N/A 6.5-7.0
    N/A Fuji N/A N/A 7.0

    1assuming 1-micron line thickness

    2average based on fewer measurements than ink of Example 3

    3pH of the substrate determined using solution indicator kit: VWR VW 5704-1 Universal Indicator solution (isopropanol 50% (v/v), NaOH, H2O).
  • [0332]
    The results shown in the table above suggest that it is possible that the pH of the substrate may have an effect on the resistivity of the inks printed thereon. It is contemplated that an ink that is printed on an acidic substrate will have a lower resistivity than an ink printed on a relatively more basic substrate (compare Example 3 ink printed on Epson photo paper versus the same ink printed on Canon photo paper).
  • [0333]
    It is known that Canon photo paper is coated with basic alumina, while Epson photo paper is coated with silica. See, e.g., Blum, A. E. and Eberl, E. E., Clays and Clay Minerals 52: 589-602 (2004), the contents of which are incorporated herein by reference in their entirety. Other coatings, e.g., alumina doped silica, are also known in the art. See, e.g., European Patent Application EP0995718, the contents of which are incorporated herein by reference in their entirety. It is possible that the silica coating on the Epson paper imparts acidic properties in the paper. Likewise, it is possible that the alumina coating on the Canon paper imparts less acidic properties in that paper.
  • [0334]
    The reasons for the apparent effect of substrate pH on the resistivity of the ink printed thereon are not entirely clear at this time. It is possible that, in addition to the substrate pH, other substrate characteristics, alone, or in conjunction with the presence of certain materials found in the ink formulation, may be the actual factors that cause inks printed on certain substrates to have lower resistivities than when they are printed on other substrates. Such characteristics may include the nature of coatings on the substrate and substrate porosity.
  • [0335]
    As mentioned above, Epson paper is coated with silica, while the Canon paper is coated with basic alumina. Without being bound by any particular theory, it is possible that the PVP on the nanoparticles adsorbs to some extent on the silica coating on the Epson paper, thereby exposing the silver nanoparticle surface. Adsorption of the PVP on silica may be expected, since it is known that silica has a high affinity for PVP. See, e.g., Blum, A. E. and Eberl, E. E., Clays and Clay Minerals 52: 589-602 (2004), the contents of which are incorporated herein by reference in their entirety. When the ink is subsequently cured, the exposed silver nanoparticles may be in closer contact with one another and may sinter to form a network with decreased resistivity.
  • [0336]
    It is also possible that the substrate porosity may lead to inks with decreased resistivity upon curing. Without being bound by any particular theory, it is possible that the substrate porosity, in conjunction with the presence of plasticizing agents (e.g., glycerol) in the ink formulation may be aiding in the adsorption of PVP on the substrate, thereby exposing the silver of the nanoparticles. Without being bound by any particular theory, it is possible that plasticizing agents sufficiently soften PVP such that the PVP can migrate onto the substrate and away from the silver nanoparticles. When the ink is subsequently cured, the exposed silver nanoparticles may be in closer contact with one another and may sinter to form a network with decreased resistivity.
  • EXAMPLE 5 Aqueous Ink Formulation
  • [0337]
    An ink-jet printable ink is prepared by combining 16 parts by weight of silver nanoparticles similar to those prepared in Example 1, 42 parts by weight of ethylene glycol and 42 parts by weight of water. The ink shows the following properties;
    Viscosity (25° C.) 3.9 cPs
    Surface Tension (20° C.) 58.3 dynes/cm
    Density (RT) 1.2 g/cm3
  • [0338]
    It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words that have been used are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein. Instead, the invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.

Claims (253)

  1. 1. A composition for the fabrication of an electrically conductive feature, wherein the composition comprises (a) metal nanoparticles which carry thereon a substance that is capable of substantially preventing an agglomeration of the nanoparticles and (b) a vehicle that is capable of forming a dispersion with the metal nanoparticles, the composition being suitable for the fabrication of an electrically conductive feature by using a direct-write tool.
  2. 2. The composition of claim 1, wherein the nanoparticles comprise at least one of silver, gold, copper, nickel, rhodium, palladium and platinum.
  3. 3. The composition of claim 1, wherein the nanoparticles comprise silver.
  4. 4. The composition of claim 1, wherein at least about 90% of the nanoparticles are of substantially spherical shape.
  5. 5. The composition of claim 1, wherein at least about 90% of the nanoparticles have a particle size of not more than about 80 nm.
  6. 6. The composition of claim 1, wherein at least about 80% of the nanoparticles have a particle size in the range of from about 10 nm to about 70 nm.
  7. 7. The composition of claim 1, wherein the composition is substantially free of particles having a particle size of more than about 100 nm.
  8. 8. The composition of claim 1, wherein the composition comprises at least about 10 weight percent of the nanoparticles.
  9. 9. The composition of claim 1, wherein the agglomeration-preventing substance comprises an organic substance.
  10. 10. The composition of claim 1, wherein the agglomeration-preventing substance comprises a polymer.
  11. 11. The composition of claim 10, wherein the polymer comprises units of a monomer which comprises at least one heteroatom selected from O and N.
  12. 12. The composition of claim 10, wherein the polymer comprises units of a monomer which comprises one or more of a hydroxyl group, a carbonyl group, an ether group and an amino group.
  13. 13. The composition of claim 10, wherein the polymer comprises units of at least one monomer which comprises a structural element selected from —COO—, —O—CO—O—, —C—O—C—, —CO—O—CO—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  14. 14. The composition of claim 10, wherein the polymer comprises a polymer of vinyl pyrrolidone.
  15. 15. The composition of claim 14, wherein the polymer of vinyl pyrrolidone comprises a homopolymer.
  16. 16. The composition of claim 10, wherein the polymer has a weight average molecular weight of from about 1,000 to about 100,000.
  17. 17. The composition of claim 1, wherein the vehicle is capable of dissolving the agglomeration-preventing substance.
  18. 18. The composition of claim 17, wherein the vehicle capable of dissolving the agglomeration-preventing substance comprises water.
  19. 19. The composition of claim 18, wherein the composition comprises the metallic nanoparticles in an amount greater than about 50 weight percent, based on the total weight of the composition.
  20. 20. The composition of claim 19, wherein the composition comprises the metallic nanoparticles in an amount greater than about 60 weight percent, based on the total weight of the composition.
  21. 21. The composition of claim 18, wherein the composition comprises the metallic nanoparticles in an amount greater than about 40 weight percent and less than about 90 weight percent, based on the total weight of the composition.
  22. 22. The composition of claim 21, wherein the composition comprises the metallic nanoparticles in an amount from about 50 to about 80 weight percent, based on the total weight of the composition.
  23. 23. The composition of claim 18, wherein the vehicle comprises ethanol, ethylene glycol and glycerol.
  24. 24. The composition of claim 23, wherein the vehicle comprises from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on a total weight of the vehicle.
  25. 25. The composition of claim 18, wherein the composition has a surface tension at 20° C. of not higher than about 30 cPs.
  26. 26. The composition of claim 18, wherein the composition has a surface tension at 20° C. of not higher than about 40 dynes/cm.
  27. 27. The composition of claim 1, wherein the vehicle comprises a mixture of at least two organic solvents.
  28. 28. The composition of claim 1, wherein the vehicle comprises a mixture of at least three organic solvents.
  29. 29. The composition of claim 1, wherein the vehicle comprises a protic organic solvent.
  30. 30. The composition of claim 29, wherein the vehicle comprises at least two protic organic solvents.
  31. 31. The composition of claim 30, wherein the protic organic solvents are selected from alcohols and polyols.
  32. 32. The composition of claim 1, wherein the vehicle comprises glycerol.
  33. 33. The composition of claim 1, wherein the vehicle comprises at least two solvents selected from C2-4 alkanols, C2-4 alkanediols and glycerol.
  34. 34. The composition of claim 1, wherein the vehicle comprises a C1-4 monoalkyl ether of at least one of a C2-4 alkanediol and a polyalkylene glycol.
  35. 35. The composition of claim 1, wherein the vehicle comprises ethanol, ethylene glycol and glycerol.
  36. 36. The composition of claim 35, wherein the vehicle comprises from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on a total weight of the vehicle.
  37. 37. The composition of claim 1, wherein a printed feature made from the composition can be rendered electrically conductive by heating the feature to a temperature of not higher than about 200° C.
  38. 38. The composition of claim 1, wherein an ink-jet printed feature made from the composition can be rendered electrically conductive by heating the feature to a temperature of not higher than about 150° C.
  39. 39. The composition of claim 1, wherein the composition has a viscosity at 20° C. of not higher than about 30 cPs.
  40. 40. The composition of claim 1, wherein the composition has a surface tension at 20° C. of not higher than about 40 dynes/cm.
  41. 41. The composition of claim 1, wherein the composition further comprises an adhesion promoter.
  42. 42. The composition of claim 42, wherein the adhesion promoter comprises a bismuth compound.
  43. 43. The composition of claim 1, wherein the composition is substantially free of a metal precursor compound.
  44. 44. The composition of claim 1, wherein the nanoparticles comprise nanoparticles prepared by a process which comprises a reduction of a metal compound by a polyol.
  45. 45. The composition of claim 1, wherein a resistivity of the conductive feature after heating to 200° C. is not higher than about 30 times a resistivity of a bulk metal.
  46. 46. A composition for the fabrication of a conductive feature by ink-jet printing, wherein the composition comprises (a) at least about 5 weight percent of metal nanoparticles which carry thereon an organic substance which is capable of substantially preventing an agglomeration of the nanoparticles and (b) a vehicle which comprises a mixture of organic solvents, the composition having a surface tension at 20° C. of from about 20 dynes/cm to about 40 dynes/cm and a viscosity at 20° C. of from about 5 cP to about 15 cP.
  47. 47. The composition of claim 46, wherein the nanoparticles comprise at least one of silver, gold, copper, nickel, palladium and platinum.
  48. 48. The composition of claim 46, wherein at least about 90% of the nanoparticles are of substantially spherical shape.
  49. 49. The composition of claim 46, wherein at least about 90% of the nanoparticles have a particle size of not more than about 80 nm.
  50. 50. The composition of claim 46, wherein the composition comprises at least about 10 weight percent of the nanoparticles.
  51. 51. The composition of claim 47, wherein the composition comprises at least about 15 weight percent of the nanoparticles.
  52. 52. The composition of claim 50, wherein the substance that is carried on the nanoparticles comprises a polymer, which polymer comprises units of at least one monomer which comprises a structural element selected from —COO—, —O—CO—O—, —C—O—C—, —CONR—, —CO—O—CO—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  53. 53. The composition of claim 52, wherein the polymer comprises polyvinylpyrrolidone.
  54. 54. The composition of claim 52, wherein the polymer has a weight average molecular weight of at least about 3,000.
  55. 55. The composition of claim 52, wherein a weight ratio of the metal and the polymer is from about 100:1 to about 10:1.
  56. 56. The composition of claim 52, wherein the vehicle comprises a mixture of at least three organic solvents.
  57. 57. The composition of claim 56, wherein the vehicle comprises at least one polyol.
  58. 58. The composition of claim 57, wherein the vehicle comprises glycerol.
  59. 59. The composition of claim 46, wherein the vehicle comprises at least two solvents selected from C2-4 alkanols, C2-4 alkanediols and glycerol.
  60. 60. The composition of claim 46, wherein the vehicle comprises ethanol, ethylene glycol and glycerol.
  61. 61. The composition of claim 46, wherein a printed feature made from the composition can be rendered electrically conductive by heating it to a temperature of not higher than about 150° C.
  62. 62. The composition of claim 46, wherein the composition further comprises an adhesion promoter.
  63. 63. A composition for ink-jet printing, wherein the composition comprises metal nanoparticles and is capable of being deposited in not more than two passes of an ink-jet printing head on a substrate as a line that can be rendered electrically conductive.
  64. 64. The composition of claim 63, wherein the line can be deposited in a single pass of the head.
  65. 65. The composition of claim 63, wherein the line can be rendered electrically conductive by heating it to a temperature of not higher than about 150° C.
  66. 66. The composition of claim 63, wherein the nanoparticles comprise at least one of silver, gold, copper, nickel, palladium and platinum.
  67. 67. The composition of claim 63, wherein the nanoparticles comprise silver.
  68. 68. The composition of claim 66, wherein the nanoparticles are substantially non-agglomerated.
  69. 69. The composition of claim 63, wherein the composition further comprises a mixture of organic solvents.
  70. 70. The composition of claim 63, wherein the composition further comprises ethanol, ethylene glycol and glycerol.
  71. 71. The composition of claim 69, wherein the composition has a surface tension at 20° C. of at least about 20 dynes/cm and a viscosity at 20° C. of not higher than about 30 cPs.
  72. 72. The composition of claim 63, wherein the nanoparticles comprise nanoparticles prepared by a process which comprises a reduction of a metal compound by a polyol.
  73. 73. The composition of claim 63, wherein the nanoparticles have adsorbed thereon an organic polymer.
  74. 74. The composition of claim 73, wherein the organic polymer comprises a vinyl pyrrolidone polymer.
  75. 75. The composition of claim 74, wherein a weight ratio of the metal and the vinyl pyrrolidone polymer is from about 50:1 to about 5:1.
  76. 76. The composition of claim 74, wherein the composition is substantially free of an added binder.
  77. 77. The composition of claim 63, wherein a resistivity of the line after heating to 200° C. is not higher than about 20 times a resistivity of a bulk metal.
  78. 78. The composition of claim 63, wherein a line deposited with a single pass of the head has a maximum thickness of at least about 0.3 μm.
  79. 79. A composition for providing a substrate with a metal structure, wherein the composition comprises (a) at least about 10 weight percent of substantially non-agglomerated metal nanoparticles which have adsorbed thereon a polymer and (b) a vehicle which comprises an organic solvent that is capable of dissolving the polymer, the composition having a surface tension at 20° C. of not more than about 60 dynes/cm and a viscosity at 20° C. of not higher than about 30 cP.
  80. 80. The composition of claim 79, wherein the nanoparticles comprise silver.
  81. 81. The composition of claim 80, wherein at least about 80% of the nanoparticles have a particle size of not more than about 80 nm.
  82. 82. The composition of claim 81, wherein the composition is substantially free of particles having a particle size of more than about 100 nm.
  83. 83. The composition of claim 80, wherein the composition comprises at least about 15 weight percent of the nanoparticles.
  84. 84. The composition of claim 79, wherein a weight ratio of the metal and the polymer is from about 100:1 to about 10:1.
  85. 85. The composition of claim 79, wherein the polymer comprises at least one structural element selected from —COO—, —O—CO—O—, —C—O—C—, —CONR—, —CO—O—CO—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  86. 86. The composition of claim 85, wherein the polymer comprises units of vinyl pyrrolidone.
  87. 87. The composition of claim 79, wherein the vehicle comprises at least two solvents selected from C2-4 alkanols, C2-4 alkanediols, polyalkylene glycols and glycerol.
  88. 88. The composition of claim 79, wherein the vehicle comprises ethanol, ethylene glycol and glycerol.
  89. 89. A printed metallic feature, wherein the feature comprises a metal and a vinyl pyrrolidone polymer in a weight ratio of from about 100:1 to about 5:1.
  90. 90. The feature of claim 89, wherein the metal comprises at least one of gold, silver, copper, nickel, rhodium, palladium and platinum.
  91. 91. The feature of claim 89, wherein the metal comprises silver.
  92. 92. The feature of claim 89, wherein the vinyl pyrrolidone polymer comprises polyvinylpyrrolidone.
  93. 93. The feature of claim 92, wherein the weight ratio is not lower than about 10:1.
  94. 94. The feature of claim 89, wherein the feature is electrically conductive.
  95. 95. The feature of claim 94, wherein the feature has a resistivity which is not higher than about 20 times that of a pure bulk metal.
  96. 96. The feature of claim 89, wherein the feature has a minimum size of not greater than about 150 μm.
  97. 97. A substrate which has the feature of claim 89 thereon.
  98. 98. The substrate of claim 97, wherein the substrate comprises a glass substrate.
  99. 99. The substrate of claim 97, wherein the substrate comprises a cellulose-based material.
  100. 100. The substrate of claim 97, wherein the substrate has a softening point of not higher than about 225° C.
  101. 101. The substrate of claim 97, wherein the substrate has a softening point of not higher than about 185° C.
  102. 102. The substrate of claim 97, wherein the substrate comprises at least one of a fluorinated polymer, a polyimide, an epoxy resin, a polycarbonate, a polyester, polyethylene, polypropylene, polyvinyl chloride, an ABS copolymer, a flexible fiber board, a non-woven polymeric fabric and a cloth.
  103. 103. The substrate of claim 97, wherein the feature consists essentially of silver and the vinyl pyrrolidone polymer in a weight ratio of from about 50:1 to about 20:1 and has a resistivity of not more than about 20 times that of pure bulk silver and wherein the substrate has a softening point of not higher than about 225° C.
  104. 104. The substrate of claim 103, wherein the feature has a minimum feature size of not greater than about 200 μm.
  105. 105. An interconnect which comprises the feature of claim 89.
  106. 106. An RF tag which comprises the feature of claim 89.
  107. 107. A smart card which comprises the feature of claim 89.
  108. 108. A flat panel display which comprises the feature of claim 89.
  109. 109. An inductor-based device which comprises the feature of claim 89.
  110. 110. A security document which comprises the feature of claim 89.
  111. 111. A credit card which comprises the feature of claim 89.
  112. 112. A bank note which comprises the feature of claim 89.
  113. 113. A substrate having a metal structure thereon, wherein the metal structure comprises voids that are at least partially filled with an organic polymer.
  114. 114. The substrate of claim 113, wherein the metal comprises at least one of gold, silver, copper, nickel, palladium and platinum.
  115. 115. The substrate of claim 113, wherein the metal comprises silver.
  116. 116. The substrate of claim 113 wherein the polymer comprises a vinyl pyrrolidone polymer.
  117. 117. The substrate of claim 113, wherein the weight ratio of the metal and the polymer is from about 100:1 to about 10:1.
  118. 118. The substrate of claim 113, wherein the structure comprises a conductive feature.
  119. 119. The substrate of claim 113, wherein the structure comprises a line, a dot, a patch or a layer.
  120. 120. The substrate of claim 119, wherein the line, dot, patch or layer has a thickness of not more than about 0.5 mm.
  121. 121. The substrate of claim 113, wherein the substrate comprises a glass substrate.
  122. 122. The substrate of claim 113, wherein the substrate has a softening point of not higher than about 225° C.
  123. 123. A method for the fabrication of a conductive feature on a substrate, wherein the method comprises forming the feature by applying the composition of claim 1 to the substrate and subjecting the feature to at least one of heat, pressure and radiation to render it conductive.
  124. 124. The method of claim 123, wherein the composition is applied by ink-jet printing.
  125. 125. The method of claim 123, wherein the method comprises rendering the feature conductive without substantially decomposing the agglomeration-preventing substance.
  126. 126. The method of claim 123, wherein the nanoparticles comprise silver and the agglomeration-preventing substance comprises a vinyl pyrrolidone polymer.
  127. 127. A method for the fabrication of a conductive feature on a substrate, wherein the method comprises forming the feature by applying the composition of claim 46 to the substrate and subjecting the feature to at least one of heat, pressure and radiation to render it conductive.
  128. 128. A method for the fabrication of a conductive feature on a substrate, wherein the method comprises forming the feature by applying the composition of claim 63 to the substrate and subjecting the feature to at least one of heat and radiation to render it conductive.
  129. 129. A method for providing a substrate with a metal structure, wherein the method comprises applying the composition of claim 79 to the substrate.
  130. 130. A method for the fabrication of a conductive feature on a substrate, wherein the method comprises depositing on the substrate a composition comprising (i) metal nanoparticles which carry thereon a substance that is capable of substantially preventing an agglomeration of the nanoparticles and (ii) a liquid vehicle that comprises a solvent which is capable of dissolving the agglomeration-preventing substance; and converting the deposited composition to a conductive feature by subjecting the composition to at least one of heat, pressure and radiation.
  131. 131. The method of claim 130, wherein the nanoparticles comprise at least one of gold, silver, copper, nickel, rhodium, palladium and platinum.
  132. 132. The method of claim 130, wherein the nanoparticles comprise silver.
  133. 133. The method of claim 130, wherein at least about 90% of the nanoparticles have a particle size of less than about 80 nm.
  134. 134. The method of claim 131, wherein the composition comprises at least about 10 weight percent of the nanoparticles.
  135. 135. The method of claim 130, wherein the agglomeration-preventing substance comprises a polymer that comprises at least one structural element selected from —COO—, —O—CO—O—, —CO—O—CO—, —C—O—C—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  136. 136. The method of claim 135, wherein the polymer comprises units of vinyl pyrrolidone.
  137. 137. The method of claim 130, wherein the vehicle comprises a mixture of at least two protic organic solvents.
  138. 138. The method of claim 130, wherein the vehicle comprises at least two solvents selected from C2-4 alkanols, C2-4 alkanediols and glycerol.
  139. 139. The method of claim 130, wherein the vehicle comprises from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on a total weight of the vehicle.
  140. 140. The method of claim 130, wherein the composition has a viscosity at 20° C. of not higher than about 30 cPs and a surface tension at 20° C. of not higher than about 60 dynes/cm.
  141. 141. The method of claim 130, wherein the composition is heated to a temperature of not higher than about 200° C.
  142. 142. The method of claim 130, wherein the minimum feature size is not greater than about 150 μm.
  143. 143. The method of claim 130, wherein the substrate comprises a glass substrate.
  144. 144. The method of claim 130, wherein the substrate comprises a cellulose-based substrate.
  145. 145. The method of claim 130, wherein the substrate comprises a material having a softening point of not higher than 225° C.
  146. 146. The method of claim 130, wherein the method comprises depositing the composition by using an ink-jet device.
  147. 147. The method of claim 130, wherein the conductive feature has a resistivity of not greater than about 30 times a resistivity of a bulk metal.
  148. 148. A method for the fabrication of a conductive feature on a substrate, wherein the method comprises ink-jet printing on the substrate a composition comprising (i) at least about 10% by weight of substantially non-agglomerated silver nanoparticles which carry thereon a vinyl pyrrolidone polymer and (ii) a liquid vehicle; and converting the printed composition to a conductive feature by subjecting the composition to at least one of heat, pressure and radiation.
  149. 149. The method of claim 148, wherein the liquid vehicle comprises from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on a total weight of the liquid vehicle.
  150. 150. The method of claim 148, wherein a weight ratio of the silver and the polymer is from about 100:1 to about 10:1.
  151. 151. The method of claim 148, wherein the polymer comprises a homopolymer of vinyl pyrrolidone.
  152. 152. The method of claim 148, wherein the polymer has a weight average molecular weight of from about 3,000 to about 100,000.
  153. 153. The method of claim 148, wherein at least about 90% of the nanoparticles have a particle size of not more than about 80 nm.
  154. 154. The method of claim 148, wherein the composition has a surface tension at 20° C. of from about 20 dynes/cm to about 60 dynes/cm and a viscosity at 20° C. of from about 3 cP to about 15 cP.
  155. 155. The method of claim 148, wherein the feature has a resistivity which is not higher than about 10 times that of pure bulk silver.
  156. 156. The method of claim 148, wherein the printed composition is heated to a temperature of not higher than about 200° C.
  157. 157. The method of claim 148, wherein the feature has a minimum size of not greater than about 150 μm.
  158. 158. A conductive feature made by the method of claim 130.
  159. 159. A conductive feature made by the method of claim 148.
  160. 160. A process for producing an ink-jet printable ink for the fabrication of electric and electronic devices, wherein the process comprises combining metal nanoparticles which carry thereon a substance that is capable of substantially preventing an agglomeration of the nanoparticles with a liquid vehicle to form a dispersion that has a surface tension at 20° C. of from about 20 dynes/cm to about 60 dynes/cm and a viscosity at 20° C. of from about 3 cP to about 15 cP and a nanoparticle concentration of at least about 5% by weight.
  161. 161. The process of claim 160, wherein the nanoparticles comprise at least one of gold, silver, copper, nickel, rhodium, palladium and platinum.
  162. 162. The process of claim 160, wherein the nanoparticles comprise silver.
  163. 163. The process of claim 160, wherein at least about 90% of the nanoparticles have a particle size of not more than about 80 nm.
  164. 164. The process of claim 160, wherein the nanoparticle concentration is at least about 10% by weight.
  165. 165. The process of claim 160, wherein the agglomeration-preventing substance comprises a polymer that comprises at least one structural element selected from —COO—, —O—CO—O—, —CO—O—CO—, —C—O—C—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  166. 166. The process of claim 160, wherein the polymer comprises units of vinyl pyrrolidone.
  167. 167. The process of claim 165, wherein a weight ratio of the metal and the polymer is from about 100:1 to about 10:1.
  168. 168. The process of claim 160, wherein the liquid vehicle comprises a mixture of at least two organic solvents.
  169. 169. The process of claim 168, wherein the at least two organic solvents are selected from C2-4 alkanols, C2-4 alkanediols and glycerol.
  170. 170. The process of claim 169, wherein the liquid vehicle comprises from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on a total weight of the solvents.
  171. 171. A process for making a metal-polymer nanocomposite which comprises applying a composition comprising substantially non-agglomerated metal nanoparticles which have a polymer adsorbed thereon and a liquid vehicle onto a substrate and thereafter removing the vehicle to leave behind the nanocomposite.
  172. 172. The process of claim 171, wherein the process further comprises heating the nanocomposite to a temperature between a softening point and a decomposition point of the polymer.
  173. 173. The process of claim 171, wherein the process further comprises causing the polymer on the surface of the nanoparticles to at least partially expose metal cores of individual nanoparticles and permit direct contact therebetween.
  174. 174. The process of claim 173, wherein the composition further comprises a plasticizing agent, the plasticizing agent causing the polymer on the surface of the nanoparticles to at least partially expose the metal cores.
  175. 175. The process of claim 174, wherein the exposing occurs at room temperature.
  176. 176. The process of claim 174, wherein the plasticizing agent comprises a plasticizing agent selected from the group consisting of phthalic esters, phosphate esters, aliphatic acid esters, benzoates, butylates, epoxy aliphatic acid esters, glycolic acid esters, propionic acid esters, sulfonates, carboxylates, succinic acid esters, maleates, fumaric acid esters, phthalic acid esters, stearic acid esters, amides, ethers, alcohols, and lactones.
  177. 177. The process of claim 176, wherein the plasticizing agent comprises ethanol, ethylene glycol, glycerol, dioctyl phthalate, dibutyl phthalate, or dialkyl adipate.
  178. 178. The process of claim 173, wherein the composition further comprises a surfactant.
  179. 179. The process of claim 178, wherein the surfactant comprises a surfactant selected from the group consisting of fatty acid esters, fatty amines, glycerol, and glycerol esters.
  180. 180. The process of claim 171, wherein the nanoparticles comprise at least one of silver, gold, copper, nickel, rhodium, palladium and platinum.
  181. 181. The process of claim 171, wherein the nanoparticles comprise silver.
  182. 182. The process of claim 171, wherein the polymer comprises units of a monomer which comprises at least one heteroatom selected from O and N.
  183. 183. The process of claim 171, wherein the polymer comprises units of a monomer which comprises one or more of a hydroxyl group, a carbonyl group, an ether group and an amino group.
  184. 184. The process of claim 171, wherein the polymer comprises units of at least one monomer which comprises a structural element selected from —COO—, —O—CO—O—, —C—O—C—, —CO—O—CO—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  185. 185. The process of claim 171, wherein the polymer comprises a polymer of vinyl pyrrolidone.
  186. 186. The process of claim 185, wherein the polymer of vinyl pyrrolidone comprises a homopolymer.
  187. 187. A metal-polymer nanocomposite comprising a substantially uniform mixture of a metal and an organic material wherein the metal and the organic material form substantially uniform inclusions having a size of from about 5 nm to about 60 nm.
  188. 188. The nanocomposite of claim 187, wherein the metal comprises at least one of silver, gold, copper, nickel, rhodium, palladium and platinum.
  189. 189. The nanocomposite of claim 187, wherein the metal comprises silver.
  190. 190. The nanocomposite of claim 187, wherein the organic material comprises a polymer.
  191. 191. The nanocomposite of claim 190, wherein the polymer comprises units of a monomer which comprises at least one heteroatom selected from O and N.
  192. 192. The nanocomposite of claim 190, wherein the polymer comprises units of a monomer which comprises one or more of a hydroxyl group, a carbonyl group, an ether group and an amino group.
  193. 193. The nanocomposite of claim 190, wherein the polymer comprises units of at least one monomer which comprises a structural element selected from —COO—, —O—CO—O—, —C—O—C—, —CO—O—CO—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  194. 194. The nanocomposite of claim 190, wherein the polymer comprises a polymer of vinyl pyrrolidone.
  195. 195. The nanocomposite of claim 194, wherein the polymer of vinyl pyrrolidone comprises a homopolymer.
  196. 196. A metal-polymer nanocomposite comprising a substantially uniform mixture of a metal and an organic material wherein the metal and the organic material form substantially uniform inclusions and wherein the metal inclusions are physically necked together.
  197. 197. The nanocomposite of claim 196, wherein the organic material accounts for not more than about 50% by volume of the nanocomposite.
  198. 198. The nanocomposite of claim 196, wherein the organic material accounts for not more than about 25% by volume of the nanocomposite.
  199. 199. The nanocomposite of claim 196, wherein the metal comprises at least one of silver, gold, copper, nickel, rhodium, palladium and platinum.
  200. 200. The nanocomposite of claim 196, wherein the organic material comprises a polymer.
  201. 201. The nanocomposite of claim 200, wherein the polymer comprises units of a monomer which comprises at least one heteroatom selected from O and N.
  202. 202. The nanocomposite of claim 200, wherein the polymer comprises units of a monomer which comprises one or more of a hydroxyl group, a carbonyl group, an ether group and an amino group.
  203. 203. The nanocomposite of claim 200, wherein the polymer comprises units of at least one monomer which comprises a structural element selected from —COO—, —O—CO—O—, —C—O—C—, —CO—O—CO—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  204. 204. The nanocomposite of claim 200, wherein the polymer comprises a polymer of vinyl pyrrolidone.
  205. 205. The nanocomposite of claim 204, wherein the polymer of vinyl pyrrolidone comprises a homopolymer.
  206. 206. A process for the fabrication of a metallic feature on a substrate, wherein the process comprises forming the feature by printing a composition which comprises substantially non-agglomerated metal nanoparticles which carry a polymer on a surface thereof on a substrate and subjecting the feature to at least one of heat, pressure and radiation.
  207. 207. The process of claim 206, wherein the nanoparticles comprise at least one of silver, gold, copper, nickel, rhodium, palladium and platinum.
  208. 208. The process of claim 206, wherein the nanoparticles comprise silver.
  209. 209. The process of claim 206, wherein the polymer comprises units of a monomer which comprises at least one heteroatom selected from O and N.
  210. 210. The process of claim 206, wherein the polymer comprises units of a monomer which comprises one or more of a hydroxyl group, a carbonyl group, an ether group and an amino group.
  211. 211. The process of claim 206, wherein the polymer comprises units of at least one monomer which comprises a structural element selected from —COO—, —O—CO—O—, —C—O—C—, —CO—O—CO—, —CONR—, —NR—CO—O—, —NR1—CO—NR2—, —CO—NR—CO—, —SO2—NR— and —SO2—O—, wherein R, R1 and R2 each independently represent hydrogen or an organic radical.
  212. 212. The process of claim 206, wherein the polymer comprises a polymer of vinyl pyrrolidone.
  213. 213. The process of claim 212, wherein the polymer of vinyl pyrrolidone comprises a homopolymer.
  214. 214. The process of claim 206, wherein the process comprises printing an adhesion material on the substrate and printing the metal nanoparticle composition on the adhesion material.
  215. 215. The process of claim 214, wherein the adhesion material is selected from a metal, a metal oxide, a low-melting glass and combinations thereof.
  216. 216. The process of claim 215, wherein the substrate comprises a glass substrate.
  217. 217. The process of claim 206, wherein the process comprises printing a black-colored material on the substrate and printing the metal nanoparticle composition on the black-colored material.
  218. 218. The process of claim 217, wherein the black-colored material is selected from a carbon-containing material, a metal oxide, and combinations thereof.
  219. 219. The process of claim 218, wherein the metal oxide is selected from chromium oxide, ruthenium oxide, cobalt oxide, and combinations thereof.
  220. 220. The process of claim 206, wherein the process comprises printing a diffusion barrier material on the substrate and printing the metal nanoparticle composition on the diffusion barrier material.
  221. 221. The process of claim 220, wherein the diffuision barrier material comprises nickel and the metal comprises silver.
  222. 222. The process of claim 206, wherein the process comprises printing a protective material on the metallic feature at least one of before and after subjecting the feature to at least one of heat, pressure and radiation.
  223. 223. An ink, comprising:
    liquid vehicle; and
    metallic nanoparticles in an amount greater than about 40 weight percent, based on the total weight of the ink.
  224. 224. The ink of claim 223, wherein the ink is suitable for direct write printing applications.
  225. 225. The ink of claim 223, wherein the ink comprises the metallic nanoparticles in an amount greater than about 50 weight percent, based on the total weight of the ink.
  226. 226. The ink of claim 225, wherein the ink comprises the metallic nanoparticles in an amount greater than about 60 weight percent, based on the total weight of the ink.
  227. 227. The ink of claim 223, wherein the ink comprises the metallic nanoparticles in an amount greater than about 40 weight percent and less than about 90 weight percent, based on the total weight of the ink.
  228. 228. The ink of claim 227, wherein the ink comprises the metallic nanoparticles in an amount from about 50 to about 80 weight percent, based on the total weight of the ink.
  229. 229. The ink of claim 223, wherein the ink has a surface tension of from about 25 to about 70 dynes/cm.
  230. 230. The ink of claim 223, wherein the ink has a viscosity of from about 8 to about 25 centipoise.
  231. 231. The ink of claim 223, wherein the metallic nanoparticles comprise a metal selected from the group consisting of: silver, gold, platinum, palladium, iron, nickel, copper, rhodium and alloys thereof.
  232. 232. The ink of claim 223, wherein the liquid vehicle has a viscosity, in the absence of the nanoparticles, of from about 1 to about 25 cPs.
  233. 233. The ink of claim 223, wherein the liquid vehicle has a surface tension, in the absence of the nanoparticles, of from about 25 to about 70 dynes/cm.
  234. 234. The ink of claim 223, wherein the ink has substantially no sedimentation after 7 days at room temperature.
  235. 235. The ink of claim 223, wherein the metallic nanoparticles have an average particle size of less than about 500 nm.
  236. 236. The ink of claim 235, wherein the metallic nanoparticles have an average particle size of less than about 100 nm.
  237. 237. The ink of claim 231, wherein the metal comprises silver.
  238. 238. The ink of claim 223, wherein at least about 90% of the nanoparticles are of substantially spherical shape.
  239. 239. The ink of claim 223, wherein at least about 90% of the nanoparticles have a particle size of not more than about 80 nm.
  240. 240. The ink of claim 223, wherein at least about 80% of the nanoparticles have a particle size in the range of from about 10 nm to about 70 nm.
  241. 241. The ink of claim 223, wherein the ink is substantially free of particles having a particle size of more than about 100 nm.
  242. 242. The ink of claim 223, wherein the ink comprises at least about 10 weight percent of the nanoparticles.
  243. 243. The ink of claim 223, wherein the ink further comprises an agglomeration-preventing substance, the agglomeration-preventing substance comprising an organic substance.
  244. 244. The ink of claim 243, wherein the agglomeration-preventing substance comprises a polymer.
  245. 245. The ink of claim 244, wherein the polymer comprises a polymer of vinyl pyrrolidone.
  246. 246. The ink of claim 245, wherein the polymer of vinyl pyrrolidone comprises a homopolymer.
  247. 247. The ink of claim 223, wherein the vehicle is capable of dissolving the agglomeration-preventing substance.
  248. 248. The ink of claim 247, wherein the vehicle capable of dissolving the agglomeration-preventing substance comprises water.
  249. 249. The ink of claim 223, wherein the vehicle comprises ethanol, ethylene glycol and glycerol.
  250. 250. The ink of claim 249, wherein the vehicle comprises from about 35% to about 45% by weight of ethylene glycol, from about 30% to about 40% by weight of ethanol and from about 20% to about 30% by weight of glycerol, based on a total weight of the vehicle.
  251. 251. The ink of claim 223, wherein the ink has a viscosity at 20° C. of not higher than about 30 cPs.
  252. 252. The ink of claim 223, wherein the ink has a surface tension at 20° C. of not higher than about 40 dynes/cm.
  253. 253. The ink of claim 223, wherein the nanoparticles comprise nanoparticles prepared by a process which comprises a reduction of a metal compound by a polyol.
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Cited By (130)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060292777A1 (en) * 2005-06-27 2006-12-28 3M Innovative Properties Company Method for making electronic devices using metal oxide nanoparticles
US20070042434A1 (en) * 2003-05-14 2007-02-22 Petra Von Stein Method for identifying tff2 regulating agents and agents identified using said method
US20070144305A1 (en) * 2005-12-20 2007-06-28 Jablonski Gregory A Synthesis of Metallic Nanoparticle Dispersions
GB2436739A (en) * 2006-03-31 2007-10-03 Int Rectifier Corp Process for fabricating a semiconductor package
US20070281177A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Colored Reflective Features And Inks And Processes For Making Them
US20070281136A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Ink jet printed reflective features and processes and inks for making them
US20070281091A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Polyimide insulative layers in multi-layered printed electronic features
US20070281140A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Colored reflective features and inks and processes for making them
US20070278422A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Printable reflective features formed from multiple inks and processes for making them
US20070279182A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Printed resistors and processes for forming same
US20070277685A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Process for printing features with smaller dimensions
US20070281099A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Solderable pads utilizing nickel and silver nanoparticle ink jet inks
US20070279718A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Reflective features with co-planar elements and processes for making them
US20070283848A1 (en) * 2006-06-08 2007-12-13 Samsung Electro-Mechanics Co., Ltd. Metal ink composition for inkjet printing
US20070290175A1 (en) * 2006-05-31 2007-12-20 Cabot Corporation Production of metal nanoparticles from precursors having low reduction potentials
US20080060549A1 (en) * 2005-08-26 2008-03-13 Ittel Steven D Preparation of silver particles using thermoplastic polymers
US20080145560A1 (en) * 2006-09-22 2008-06-19 Oscar Khaselev Solvent systems for metals and inks
US20080145633A1 (en) * 2006-06-19 2008-06-19 Cabot Corporation Photovoltaic conductive features and processes for forming same
US20080157064A1 (en) * 2007-01-02 2008-07-03 Chunghwa Picture Tubes, Ltd. Organic thin film transistor and method for manufacturing the same
US20080158072A1 (en) * 2006-12-30 2008-07-03 Brian Matthew Logan Antenna constructions for electronic devices and methods for manufacturing such antenna constructions
WO2008097502A1 (en) * 2007-02-02 2008-08-14 The Regents Of The University Of California Massively parallel assembly of composite structures using depletion attraction
WO2008100568A1 (en) * 2007-02-17 2008-08-21 Nanogram Corporation Functional composites, functional inks and applications thereof
US20080199669A1 (en) * 2007-02-15 2008-08-21 Chun-Yu Lee Zinc oxide nanoparticle-containing organic-inorganic composite film, fabrication method for the same and electroluminescent element implemented by the same
US20080259147A1 (en) * 2007-04-23 2008-10-23 Oriakhi Christopher O Intercalated compound
US20080257204A1 (en) * 2007-04-23 2008-10-23 Oriakhi Christopher O Ink composition and method for forming the same
US20080257211A1 (en) * 2007-04-18 2008-10-23 Oriakhi Christopher O Metallic inkjet ink and method for forming the same
WO2008157612A1 (en) * 2007-06-21 2008-12-24 Enthone Inc. Codeposition of copper nanoparticles in through silicon via filling
US20080318757A1 (en) * 2007-06-19 2008-12-25 Cabot Corporation Nanoglass and flame spray processes for producing nanoglass
WO2009015020A1 (en) * 2007-07-20 2009-01-29 Fry's Metals, Inc. Electrical conductors and methods of making and using them
WO2009017648A1 (en) * 2007-07-26 2009-02-05 The Ex One Company, Llc Nanoparticle suspensions for use in the three-dimensional printing process
US20090069605A1 (en) * 2007-09-12 2009-03-12 Shanghai Huayi Acrylic Acid Co., Ltd. Catalyst composition and producing process thereof for use in manufacturing methacrolein
US20090096351A1 (en) * 2007-10-12 2009-04-16 Cabot Corporation Reflective layers for electronic devices
US20090120238A1 (en) * 2007-11-09 2009-05-14 Samsung Electro-Mechanics Co., Ltd. Method of manufacturing metal nanoparticles
US20090148978A1 (en) * 2007-12-07 2009-06-11 Cabot Corporation Processes for forming photovoltaic conductive features from multiple inks
WO2009096802A1 (en) * 2008-01-31 2009-08-06 Ydreams - Informática, S.A. Processing of electric and/or electronic elements on cellulosic material substrates
WO2009108304A1 (en) * 2008-02-26 2009-09-03 Cambrios Technologies Corporation Methods and compositions for ink jet deposition of conductive features
US20090230506A1 (en) * 2008-03-11 2009-09-17 Hynix Semiconductor Inc. Semiconductor device and method for fabricating the same
US20090242854A1 (en) * 2008-03-05 2009-10-01 Applied Nanotech Holdings, Inc. Additives and modifiers for solvent- and water-based metallic conductive inks
US20090252924A1 (en) * 2005-11-04 2009-10-08 Mitsui Mining & Smelting Co., Ltd. Nickel ink and conductor film formed of nickel ink
US20090281635A1 (en) * 2008-05-09 2009-11-12 Boston Scientific Scimed, Inc. Antimicrobial medical devices
US20090281558A1 (en) * 2008-05-09 2009-11-12 Boston Scientific Scimed, Inc. Surgical meshes with radiopaque coatings
US20090297829A1 (en) * 2008-06-02 2009-12-03 Bayer Materialscience Llc Process for incorporating metal nanoparticles in a polymeric article and articles made therewith
EP2131979A2 (en) * 2007-03-01 2009-12-16 Pchem Associates, Inc. Shielding based on metallic nanoparticle compositions and devices and methods thereof
WO2010003056A1 (en) * 2008-07-02 2010-01-07 Applied Nanotech Holdings, Inc. Metallic pastes and inks
US20100015462A1 (en) * 2008-02-29 2010-01-21 Gregory Jablonski Metallic nanoparticle shielding structure and methods thereof
US20100041133A1 (en) * 2008-08-13 2010-02-18 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Biological targeting compositions and methods of using the same
US20100040546A1 (en) * 2008-08-13 2010-02-18 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Biological targeting compositions and methods of using the same
US20100042072A1 (en) * 2008-08-13 2010-02-18 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Biological targeting compositions and methods of using the same
US20100084599A1 (en) * 2008-10-03 2010-04-08 Lewis Jennifer A Metal nanoparticle inks
US20100127223A1 (en) * 2008-11-24 2010-05-27 E. I. Du Pont De Nemours And Company High conductivity polymer thick film silver conductor composition for use in rfid and other applications
US20100140550A1 (en) * 2008-11-20 2010-06-10 Eos Gmbh Electro Optical Systems Method for identifying laser sintering powders
US20100151120A1 (en) * 2008-12-12 2010-06-17 Tsinghua University Method for making conductive wires
US7751208B2 (en) 2007-03-30 2010-07-06 Cambridge Semiconductor Limited Forward power converter controllers
US20100173095A1 (en) * 2009-01-07 2010-07-08 Tsinghua University Inkjet ink and method for making conductive wires using the same
WO2010114769A1 (en) * 2009-03-31 2010-10-07 Applied Nanotech Holdings, Inc. Metallic ink
US20100255290A1 (en) * 2009-04-07 2010-10-07 Tsinghua University Carbon nanotube metal nanoparticle composite and method for making the same
US20100269635A1 (en) * 2005-01-14 2010-10-28 Cabot Corporation Production of metal nanoparticles
US20100269634A1 (en) * 2005-01-14 2010-10-28 Cabot Corporation Production of metal nanoparticles
US20100323102A1 (en) * 2009-06-23 2010-12-23 Xerox Corporation System and Method for Preparing Conductive Structures Using Radiation Curable Phase Change Gel Inks
US20110092961A1 (en) * 2008-08-13 2011-04-21 Searete Llc Artificial cells
US7931941B1 (en) 2004-10-29 2011-04-26 Pchem Associates, Inc. Synthesis of metallic nanoparticle dispersions capable of sintering at low temperatures
WO2011053811A1 (en) * 2009-10-30 2011-05-05 The Board Of Trustees Of The Leland Stanford Junior University Conductive fibrous materials
US20110115086A1 (en) * 2009-11-13 2011-05-19 Xerox Corporation Metal nonoparticle compositions
US20110169888A1 (en) * 2005-09-12 2011-07-14 Electronics For Imaging, Inc. Metallic ink jet printing system for graphics applications
US7994640B1 (en) 2007-07-02 2011-08-09 Novellus Systems, Inc. Nanoparticle cap layer
US20110215279A1 (en) * 2010-03-04 2011-09-08 Lockheed Martin Corporation Compositions containing tin nanoparticles and methods for use thereof
CN102189788A (en) * 2010-03-17 2011-09-21 精工爱普生株式会社 Printing device and printing method
US8033715B2 (en) 2007-11-08 2011-10-11 Illinois Institute Of Technology Nanoparticle based thermal history indicators
US8039379B1 (en) * 2007-07-02 2011-10-18 Novellus Systems, Inc. Nanoparticle cap layer
US20120020033A1 (en) * 2009-02-04 2012-01-26 Bare Conductive Ltd Skin-Safe Conductive Ink and Method for Application on the Body
US8158032B2 (en) * 2010-08-20 2012-04-17 Xerox Corporation Silver nanoparticle ink composition for highly conductive features with enhanced mechanical properties
US20120100374A1 (en) * 2008-09-15 2012-04-26 Lockheed Martin Corporation Metal nanoparticles and methods for producing and using same
WO2012075394A1 (en) * 2010-12-02 2012-06-07 Applied Nanotech Holdings, Inc. Nanoparticle inks for solar cells
US20120178241A1 (en) * 2011-01-07 2012-07-12 International Business Machines Corporation Conductive metal and diffusion barrier seed compositions, and methods of use in semiconductor and interlevel dielectric substrates
WO2012105310A1 (en) * 2011-02-02 2012-08-09 コニカミノルタホールディングス株式会社 Organic electroluminescence element and illumination device
US8278216B1 (en) 2006-08-18 2012-10-02 Novellus Systems, Inc. Selective capping of copper
US20120279766A1 (en) * 2011-05-06 2012-11-08 Xerox Corporation Method of fabricating high-resolution features
US20120308720A1 (en) * 2007-04-19 2012-12-06 Mitsubishi Materials Corporation Conductive reflective film and production method thereof
US8334464B2 (en) 2005-01-14 2012-12-18 Cabot Corporation Optimized multi-layer printing of electronics and displays
US20120319152A1 (en) * 2011-06-14 2012-12-20 Won Hwa Park Light emitting device package
US8383014B2 (en) 2010-06-15 2013-02-26 Cabot Corporation Metal nanoparticle compositions
WO2013036523A1 (en) * 2011-09-06 2013-03-14 Henkel Corporation Conductive material and process
US20130062555A1 (en) * 2011-09-11 2013-03-14 Acta Technology Inc Nanofluids and a method of making nanofluids for ground source heat pumps and other applications
US8422197B2 (en) 2009-07-15 2013-04-16 Applied Nanotech Holdings, Inc. Applying optical energy to nanoparticles to produce a specified nanostructure
US8499445B1 (en) * 2011-07-18 2013-08-06 Endicott Interconnect Technologies, Inc. Method of forming an electrically conductive printed line
US8512417B2 (en) 2008-11-14 2013-08-20 Dune Sciences, Inc. Functionalized nanoparticles and methods of forming and using same
US20130222496A1 (en) * 2010-12-23 2013-08-29 Hewlett-Packard Development Company, L.P. Optically clear fluid composition
US20130305943A1 (en) * 2011-02-08 2013-11-21 Lg Chem, Ltd. Ink composition for printing, and printing method using same
CN103430241A (en) * 2011-02-28 2013-12-04 无限科技全球公司 Metallic nanofiber ink, substantially transparent conductor, and fabrication method
US8623938B2 (en) 2010-12-31 2014-01-07 Tsinghua University Inkjet ink and method for making the same
WO2014011578A1 (en) * 2012-07-09 2014-01-16 Applied Nanotech Holdings, Inc. Photosintering of micron-sized copper particles
US8647979B2 (en) 2009-03-27 2014-02-11 Applied Nanotech Holdings, Inc. Buffer layer to enhance photo and/or laser sintering
WO2014028280A2 (en) * 2012-08-16 2014-02-20 Nthdegree Technologies Worldwide Inc. Conductive, metallic and semiconductor ink compositions
US20140072720A1 (en) * 2012-05-22 2014-03-13 University Of Massachusetts Patterned nanoparticle structures
US20140178601A1 (en) * 2011-09-06 2014-06-26 Henkel IP & Holding GmbH Conductive material and process
US20140197354A1 (en) * 2011-09-11 2014-07-17 Acta Technology Inc. Method of making nanaofluids for ground souce heat pumps and other applications
US20140262443A1 (en) * 2013-03-14 2014-09-18 Cambrios Technologies Corporation Hybrid patterned nanostructure transparent conductors
US20140287159A1 (en) * 2013-03-21 2014-09-25 Intrinsiq Materials, Inc. Conductive paste formulations for improving adhesion to plastic substrates
US8846778B2 (en) 2008-12-22 2014-09-30 Canadian Bank Note Company, Limited Method and composition for printing tactile marks and security document formed therefrom
US8865027B2 (en) 2005-08-12 2014-10-21 Cambrios Technologies Corporation Nanowires-based transparent conductors
US20140356524A1 (en) * 2013-05-31 2014-12-04 Basf Corporation Nanostructure Dispersions And Transparent Conductors
US20150034996A1 (en) * 2013-08-01 2015-02-05 Epistar Corporation Light-emitting device
US20150056426A1 (en) * 2012-02-29 2015-02-26 Yisum Research Development Company Of The Hebrew University Of Jerusalem Ltd. Inks containing metal precursors nanoparticles
US8968824B2 (en) * 2013-03-14 2015-03-03 Dowa Electronics Materials Co., Ltd. Method for producing silver conductive film
US20150069649A1 (en) * 2013-09-12 2015-03-12 The Exone Company Powder Particle Layerwise Three-Dimensional Printing Process
US9011570B2 (en) 2009-07-30 2015-04-21 Lockheed Martin Corporation Articles containing copper nanoparticles and methods for production and use thereof
US20150125624A1 (en) * 2013-11-01 2015-05-07 Tyco Electronics Corporation Spray Application Process for Three Dimensional Articles
WO2015073933A1 (en) * 2013-11-15 2015-05-21 University Of Utah Research Foundation Nanoparticle light filtering method and apparatus
US9072185B2 (en) 2009-07-30 2015-06-30 Lockheed Martin Corporation Copper nanoparticle application processes for low temperature printable, flexible/conformal electronics and antennas
US20150191611A1 (en) * 2012-06-19 2015-07-09 Chameleon Innovations Australia (Cia) Pty Ltd Composition
US9088071B2 (en) 2010-11-22 2015-07-21 ChamTech Technologies, Incorporated Techniques for conductive particle based material used for at least one of propagation, emission and absorption of electromagnetic radiation
US9139917B2 (en) 2009-10-16 2015-09-22 Paul Gregory O'BRIEN Transparent conductive porous nanocomposites and methods of fabrication thereof
US9196760B2 (en) 2011-04-08 2015-11-24 Ut-Battelle, Llc Methods for producing complex films, and films produced thereby
EP2930722A4 (en) * 2012-12-07 2015-12-09 Fujifilm Corp Process for manufacturing conductive film and printed wiring board
US9231212B2 (en) 2011-05-23 2016-01-05 Koninklijke Philips N.V. Fabrication apparatus for fabricating a layer structure
US20160009930A1 (en) * 2014-07-09 2016-01-14 Patrick Pagani Radio frequency indentification (rfid) ink
US9312404B2 (en) 2006-06-30 2016-04-12 Mitsubishi Materials Corporation Composition for manufacturing electrode of solar cell, method of manufacturing same electrode, and solar cell using electrode obtained by same method
US20160118156A1 (en) * 2013-06-07 2016-04-28 Seiko Pmc Corporation Metal nanowire-containing composition
DE102014117519A1 (en) * 2014-11-28 2016-06-02 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. A process for the preparation and testing of workpieces and workpiece
US9378861B2 (en) 2009-11-30 2016-06-28 Lockheed Martin Corporation Nanoparticle composition and methods of making the same
US20160281229A1 (en) * 2012-11-29 2016-09-29 Lg Chem, Ltd. Gas barrier film with protective coating layer containing inorganic particles
US9472787B2 (en) 2011-05-23 2016-10-18 Oledworks Gmbh Fabrication apparatus for fabricating a patterned layer
US9533523B2 (en) 2006-05-31 2017-01-03 Sicpa Holding Sa Reflective features with co-planar elements and processes for making them
US20170015849A1 (en) * 2014-02-28 2017-01-19 Dnp Fine Chemicals Co., Ltd. Ink composition for inkjet recording, method for producing printed material, and printing method
US9603260B2 (en) 2009-11-13 2017-03-21 Teknologian Tutkimuskeskus Vtt Oy Method and products related to deposited particles
US9606277B2 (en) 2011-01-17 2017-03-28 University Of Utah Research Foundation Apparatus and methods for reducing frequency or severity of photophobic responses or modulating circadian cycles
US9730333B2 (en) 2008-05-15 2017-08-08 Applied Nanotech Holdings, Inc. Photo-curing process for metallic inks
US9764157B2 (en) 2011-01-17 2017-09-19 University Of Utah Research Foundation Methods, systems, and apparatus for reducing the frequency and/or severity of photophobic responses or for modulating circadian cycles
US9899234B2 (en) 2014-06-30 2018-02-20 Lam Research Corporation Liner and barrier applications for subtractive metal integration
KR101860603B1 (en) 2011-09-06 2018-05-23 헨켈 아이피 앤드 홀딩 게엠베하 Conductive material and process

Families Citing this family (113)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE69819740T2 (en) * 1997-02-24 2004-09-30 Superior Micropowders Llc, Albuquerque Aerosol method and apparatus, particulate products, electronic devices and products thereof
US8167393B2 (en) 2005-01-14 2012-05-01 Cabot Corporation Printable electronic features on non-uniform substrate and processes for making same
WO2006076605A3 (en) * 2005-01-14 2006-11-23 Cabot Corp Circuit modeling and selective deposition
WO2006076607A1 (en) * 2005-01-14 2006-07-20 Cabot Corporation Ink-jet printing of passive electricalcomponents
WO2006076604A3 (en) * 2005-01-14 2006-09-21 Cabot Corp Processes for planarizing substrates and encapsulating printable electronic features
US7547347B2 (en) * 2005-05-13 2009-06-16 University Of Rochester Synthesis of nano-materials in ionic liquids
US7732330B2 (en) 2005-06-30 2010-06-08 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device and manufacturing method using an ink-jet method of the same
KR100716201B1 (en) * 2005-09-14 2007-05-10 삼성전기주식회사 Metal nanoparticles and method for manufacturing thereof
US9149545B2 (en) * 2005-11-02 2015-10-06 General Electric Company Nanoparticle-based imaging agents for X-ray/computed tomography and methods for making same
US8703235B2 (en) * 2007-02-23 2014-04-22 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Preparation of metal nanowire decorated carbon allotropes
KR100790948B1 (en) * 2006-05-25 2008-01-03 삼성전기주식회사 Method for preparing metal nanoparticles and metal nanoparticles prepared using the same
US7967891B2 (en) 2006-06-01 2011-06-28 Inco Limited Method producing metal nanopowders by decompositon of metal carbonyl using an induction plasma torch
WO2007149881A3 (en) * 2006-06-19 2008-03-13 Cabot Corp Metal-containing nanoparticles, their synthesis and use
US8454721B2 (en) * 2006-06-21 2013-06-04 Cambrios Technologies Corporation Methods of controlling nanostructure formations and shapes
KR100836659B1 (en) * 2006-07-06 2008-06-10 삼성전기주식회사 Method for manufacturing metal nanoparticles
KR100790458B1 (en) * 2006-07-10 2008-01-02 삼성전기주식회사 Copper nano-particles and preparation method thereof
US7615096B1 (en) * 2006-07-28 2009-11-10 National Taiwan University Method for manufacturing metal nanoparticle
CN101511952B (en) * 2006-08-07 2012-07-25 印可得株式会社 Process for preparation of silver nanoparticles, and the compositions of silver ink containing the same
US7736485B2 (en) * 2006-08-11 2010-06-15 Aqua Resources Corporation Nanoplatelet magnesium hydroxides and methods of preparing same
US8822030B2 (en) 2006-08-11 2014-09-02 Aqua Resources Corporation Nanoplatelet metal hydroxides and methods of preparing same
US20080085410A1 (en) * 2006-10-06 2008-04-10 General Electric Company Composition and associated method
JP5309521B2 (en) 2006-10-11 2013-10-09 三菱マテリアル株式会社 Forming an electrode method using an electrode-forming composition and a method for manufacturing the same, and the composition
US8246814B2 (en) * 2006-10-20 2012-08-21 Saudi Arabian Oil Company Process for upgrading hydrocarbon feedstocks using solid adsorbent and membrane separation of treated product stream
DE102007037079A1 (en) * 2006-10-25 2008-04-30 Bayer Materialscience Ag Formulation for use in generation of electrical conductive or optical coatings, comprises silver metal particles, solvent, dispersion agent and additives
KR100874709B1 (en) * 2006-11-14 2008-12-18 광주과학기술원 Synthesis and application of groundwater treatment of zero-valent iron nanowires
US8088193B2 (en) * 2006-12-16 2012-01-03 Taofang Zeng Method for making nanoparticles
ES2304101B1 (en) * 2007-02-16 2009-08-13 Universidad De La Rioja Method of production of silver nanoparticles.
US7854997B2 (en) * 2007-02-28 2010-12-21 The Boeing Company Adherends with enhanced surfaces
US7680553B2 (en) * 2007-03-08 2010-03-16 Smp Logic Systems Llc Methods of interfacing nanomaterials for the monitoring and execution of pharmaceutical manufacturing processes
KR100850874B1 (en) 2007-04-23 2008-08-07 전자부품연구원 Manufacturing method of ni nano-particles, ni nano-particles and ink composition comprising the same
KR20090010477A (en) * 2007-07-23 2009-01-30 삼성전기주식회사 Method for manufacturing nickel nanoparticles
KR101104123B1 (en) * 2007-08-09 2012-01-13 (주) 파루 Silver Nanogels for Conductive Inks
EP2190614A2 (en) * 2007-09-19 2010-06-02 E. I. du Pont de Nemours and Company Preparation of silver spheres by the reduction of silver polyamine complexes
KR100922810B1 (en) * 2007-12-11 2009-10-21 주식회사 잉크테크 A method for fabricating blackened conductive patterns
WO2009082493A1 (en) * 2007-12-24 2009-07-02 Saudi Arabian Oil Company Membrane desulfurization of liquid hydrocarbon feedstreams
WO2009126341A3 (en) * 2008-01-14 2009-12-23 Taofang Zeng Method for making nanoparticles or fine particles
US7922787B2 (en) * 2008-02-02 2011-04-12 Seashell Technology, Llc Methods for the production of silver nanowires
US7977240B1 (en) 2008-02-13 2011-07-12 Kovio, Inc. Metal inks for improved contact resistance
US8038926B2 (en) * 2008-03-07 2011-10-18 Drexel University Method for making carbon nanotubes with embedded nanoparticles
EP2262851B1 (en) * 2008-03-13 2017-09-27 Board of Regents, The University of Texas System Covalently functionalized particles for synthesis of new composite materials
US8852316B2 (en) * 2008-04-28 2014-10-07 Tata Chemicals Limited Process for the preparation of silver nano particles
WO2010002922A3 (en) * 2008-06-30 2010-05-14 Life Technologies Corporation Methods for isolating and purifying nanoparticles from a complex medium
WO2010010026A3 (en) * 2008-07-23 2010-06-03 Construction Research & Technology Gmbh Method for producing metal nanoparticles in polyols
KR20100016821A (en) * 2008-08-05 2010-02-16 삼성전기주식회사 Preparing method of nickel nanoparticles
KR100978671B1 (en) * 2008-08-05 2010-08-30 삼성전기주식회사 Metal nanoparticle dispersion
CN102119182B (en) * 2008-08-08 2013-02-06 建筑研究和技术有限公司 Production of silylated polyurethane and/or polyurea
US8419822B2 (en) * 2008-08-18 2013-04-16 Xerox Corporation Methods for producing carboxylic acid stabilized silver nanoparticles
US8298314B2 (en) * 2008-08-18 2012-10-30 Xerox Corporation Silver nanoparticles and process for producing same
KR101127056B1 (en) * 2008-09-25 2012-03-23 삼성전기주식회사 Method for preparing metal nanoparticles using matal seed and metal nanoparticles comprising metal seed
KR101089299B1 (en) * 2008-11-18 2011-12-02 광 석 서 Method for producing metal nanowire using ionic liquid
DE102009015470A1 (en) * 2008-12-12 2010-06-17 Byk-Chemie Gmbh A method for producing metal nanoparticles and metal nanoparticles obtained in this manner and their use
WO2010100107A3 (en) * 2009-03-02 2010-11-11 Colorobbia Italia S.P.A. Process for preparing stable suspensions of metal nanoparticles and the stable colloidal suspensions obtained thereby
US8277651B2 (en) 2009-03-13 2012-10-02 Terrasep, Llc Methods and apparatus for centrifugal liquid chromatography
US20100242679A1 (en) * 2009-03-29 2010-09-30 Yi-Hsiuan Yu Method for continuously fabricating silver nanowire
US9273378B2 (en) 2009-04-24 2016-03-01 Japan Science And Technology Agency Fine solid solution alloy particles and method for producing same
US20110024159A1 (en) * 2009-05-05 2011-02-03 Cambrios Technologies Corporation Reliable and durable conductive films comprising metal nanostructures
CN102460600B (en) * 2009-05-05 2016-06-01 凯博瑞奥斯技术公司 Comprising a reliable and durable conductive film metallic nanostructures
US20110000823A1 (en) * 2009-07-01 2011-01-06 Feras Hamad Membrane desulfurization of liquid hydrocarbons using an extractive liquid membrane contactor system and method
US20110023658A1 (en) * 2009-08-03 2011-02-03 Seashell Technology, Llc Methods For The Production Of Silver Nanocubes
US8541098B2 (en) * 2009-08-24 2013-09-24 Cambrios Technology Corporation Purification of metal nanostructures for improved haze in transparent conductors made from the same
CN102762324B (en) * 2009-08-25 2016-06-08 凯博瑞奥斯技术公司 Control of a method for metallic nanostructures
GB0915251D0 (en) * 2009-09-02 2009-10-07 Univ Bangor Low temperature platinisation for dye-sensitised solar cells
WO2011038309A1 (en) * 2009-09-26 2011-03-31 Ferro Corporation Silver ribbons, methods of their making and applications thereof
US8741801B2 (en) * 2009-11-23 2014-06-03 The Research Foundation For The State University Of New York Catalytic platinum and its 3d-transition-metal alloy nanoparticles
US8592339B2 (en) * 2009-11-23 2013-11-26 The Research Foundation For The State University Of New York Catalytic platinum-copper alloy nanoparticles
FR2954361B1 (en) 2009-12-23 2012-06-15 Arjo Wiggins Fine Papers Ltd printable sheet ultra smooth and recyclable and process for its manufacture
US8569894B2 (en) 2010-01-13 2013-10-29 Advanced Semiconductor Engineering, Inc. Semiconductor package with single sided substrate design and manufacturing methods thereof
US20110218304A1 (en) * 2010-03-03 2011-09-08 Tecona Technologies, Inc. Low cost and high yield method of making large quantity and homogenous metal nanoparticles and controlling their solubility
US8405213B2 (en) 2010-03-22 2013-03-26 Advanced Semiconductor Engineering, Inc. Semiconductor package including a stacking element
GB201011660D0 (en) * 2010-07-09 2010-08-25 Birkeland Innovasjon As Process
US8641798B2 (en) * 2010-07-13 2014-02-04 The United States of America, as represented by the Secretary of Commerce, NIST One-step synthesis of monodisperse AU-CU nanocubes
WO2012011774A3 (en) 2010-07-22 2012-05-31 공주대학교산학협력단 Method for manufacturing silver nanowires
ES2350351B2 (en) * 2010-07-30 2012-02-02 Universidade De Santiago De Compostela Process for the preparation of nanoparticles in ionic liquids.
US9070793B2 (en) 2010-08-02 2015-06-30 Advanced Semiconductor Engineering, Inc. Semiconductor device packages having electromagnetic interference shielding and related methods
US9487399B2 (en) * 2010-08-17 2016-11-08 Jalaledin Ghanavi Method for the synthesis of metallic nano products
WO2012061171A3 (en) 2010-11-03 2012-09-27 Cabot Corporation Metallic dispersions for inkjet printing
WO2012074355A1 (en) * 2010-12-03 2012-06-07 Mimos Berhad Preparation of silver nanoparticles
US9017449B2 (en) * 2010-12-09 2015-04-28 Carestream Health, Inc. Nanowire preparation methods, compositions, and articles
US9017450B2 (en) * 2010-12-09 2015-04-28 Carestream Health, Inc. Nanowire preparation methods, compositions, and articles
DE102010063342A1 (en) * 2010-12-17 2012-06-21 Laser Zentrum Hannover E.V. A process for the manufacture of micro-nano combined active systems
US9406658B2 (en) 2010-12-17 2016-08-02 Advanced Semiconductor Engineering, Inc. Embedded component device and manufacturing methods thereof
CN103329049B (en) 2011-01-31 2016-03-16 惠普发展公司,有限责任合伙企业 Liquid electrophotographic ink and its preparation method
FR2971167B1 (en) * 2011-02-03 2013-03-15 Commissariat Energie Atomique A method of separating at least one element platinoide an acidic aqueous solution comprising, in addition to this element platinoide, one or more other chemical elements
US9272334B2 (en) * 2011-04-12 2016-03-01 GM Global Technology Operations LLC Synthesis of platinum-alloy nanoparticles and supported catalysts including the same
US8741026B2 (en) * 2011-05-23 2014-06-03 Carestream Health, Inc. Branched nanowire preparation methods, compositions, and articles
US8956439B2 (en) * 2011-05-23 2015-02-17 Carestream Health, Inc. Zero-valent catalysis of metal ion reduction methods, compositions, and articles
DE102011108089B4 (en) * 2011-07-18 2015-11-12 Technische Universität Dresden A process for the production of thin electrically conductive layers of silver, a silver complex, the solution as well as a use of the silver complex in a solution
US20140377126A1 (en) * 2011-09-16 2014-12-25 Japan Science And Technology Agency Ruthenium nanoparticles with essentially face-centered cubic structure and method for producing the same
DE102011085642A1 (en) * 2011-11-03 2013-05-08 Bayer Materialscience Aktiengesellschaft A method for producing a metal nanoparticle dispersion, the metal nanoparticle dispersion as well as their use
KR20130067615A (en) * 2011-12-14 2013-06-25 한국전자통신연구원 Synthesis of metal oxide nanoparticles
EP2802711B1 (en) 2012-01-13 2017-10-25 Arjo Wiggins Fine Papers Limited Method for producing a sheet
FR2985744B1 (en) * 2012-01-13 2014-11-28 Arjo Wiggins Fine Papers Ltd Method for producing an electrically conductive sheet
US20130192423A1 (en) * 2012-01-27 2013-08-01 Blue Nano Inc. Method of producing silver nanowires
RU2486033C1 (en) * 2012-04-06 2013-06-27 Федеральное государственное бюджетное учреждение науки Институт химии твердого тела и механохимии Сибирского отделения Российской академии наук (ИХТТМ СО РАН) Method of producing nano-sized powders of iron-nickel solid solution
US8721763B2 (en) * 2012-08-01 2014-05-13 Chung Shan Institute Of Science And Technology Method for separating metal nanoparticles from colloidal metal solution
DE112013004232T5 (en) 2012-08-31 2015-08-20 Corning Incorporated The silver recovery process and products produced thereby Silver
CN104685076B (en) * 2012-08-31 2017-05-31 康宁股份有限公司 Synthesis of silver and silver-low dispersion thus prepared product based on
ES2472116B1 (en) * 2012-12-27 2015-04-16 Asociación Empresarial De Investigación Centro Tecnológico Del Mueble Y La Madera De La Región De Murcia Process for manufacturing polyurethane foam with antimicrobial properties and polyurethane foam thus obtained
WO2014138749A1 (en) * 2013-03-08 2014-09-12 Innova Dynamics, Inc. Production of nanostructures
US20140349025A1 (en) * 2013-05-23 2014-11-27 E I Du Pont De Nemours And Company Conductive compositions and methods relating thereto
KR20140144807A (en) * 2013-06-11 2014-12-22 삼성디스플레이 주식회사 Fabricating method for metal nanowire and fabricating method for transparent conductor using the same
KR20150020452A (en) 2013-08-14 2015-02-26 삼성디스플레이 주식회사 Method of manufacturing silver nanowire
WO2015102863A1 (en) * 2013-12-31 2015-07-09 Rhodia Operations Processes for making silver nanostructures
US9349540B2 (en) * 2014-04-03 2016-05-24 National Chiao Tung University Method for manufacturing platinum nanoparticle solution and self-assembled platinum counter electrode thereof
KR20170018897A (en) * 2014-06-16 2017-02-20 오사카 유니버시티 Method for synthesizing silver particles, silver particles, method for manufacturing electroconductive paste, and electroconductive paste
CN104028775A (en) * 2014-06-19 2014-09-10 中国航空工业集团公司北京航空材料研究院 Preparation method for monodisperse uniform-particle-size silver nanoparticles
DE102015013238A1 (en) 2014-10-28 2016-04-28 Dow Global Technologies Llc A method of low oxygen concentration for the production of silver nanowires
DE102015013219A1 (en) 2014-10-28 2016-04-28 Dow Global Technologies Llc A process for the production of silver nanowires
CN104668575A (en) * 2014-12-02 2015-06-03 中国科学院化学研究所 Nanometer silver powder dispersible in weak solvents and application of nanometer silver powder to conductive ink preparation
US9388477B1 (en) * 2015-01-20 2016-07-12 Uchicago Argonne, Llc Noble metal superparticles and methods of preparation thereof
RU2610197C2 (en) * 2015-07-29 2017-02-08 Федеральное Государственное Унитарное Предприятие "Государственный Ордена Трудового Красного Знамени Научно-Исследовательский Институт Химических Реактивов И Особо Чистых Химических Веществ" Colloidal solution of nanosilver in ethylene-glycol and method of its production
CN105710383A (en) * 2016-04-30 2016-06-29 安徽农业大学 Method for preparing Cu powder by reducing CuO by adopting glycerinum
RU2644907C1 (en) * 2016-11-08 2018-02-14 Федеральное государственное унитарное предприятие "Институт химических реактивов и особо чистых химических веществ Национального исследовательского центра "Курчатовский институт" (НИЦ "Курчатовский институт"-ИРЕА) Method of producing ultra-high molecular polyethylene (uhmpe) impregnated by silver nanoparticles

Citations (97)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3313632A (en) * 1962-11-27 1967-04-11 Engelhard Ind Inc Gold-silver coordination compounds and decorating compositions containing same
US3814696A (en) * 1972-06-19 1974-06-04 Eastman Kodak Co Colloidal metal in non-aqueous media
US4019188A (en) * 1975-05-12 1977-04-19 International Business Machines Corporation Micromist jet printer
US4186244A (en) * 1977-05-03 1980-01-29 Graham Magnetics Inc. Novel silver powder composition
US4255291A (en) * 1979-06-21 1981-03-10 E. I. Du Pont De Nemours And Company Air-fireable conductor composition
US4266229A (en) * 1979-03-26 1981-05-05 Whittaker Corporation Light sensitive jet inks
US4333966A (en) * 1979-07-30 1982-06-08 Graham Magnetics, Inc. Method of forming a conductive metal pattern
US4381945A (en) * 1981-08-03 1983-05-03 E. I. Du Pont De Nemours And Company Thick film conductor compositions
US4508753A (en) * 1982-08-19 1985-04-02 Gte Automatic Electric Inc. Method of producing fine line conductive/resistive patterns on an insulating coating
US4517252A (en) * 1983-05-06 1985-05-14 The Boeing Company Pre-alloyed thick film conductor for use with aluminum wire bonding and method of bonding
US4650108A (en) * 1985-08-15 1987-03-17 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Method for forming hermetic seals
US4668533A (en) * 1985-05-10 1987-05-26 E. I. Du Pont De Nemours And Company Ink jet printing of printed circuit boards
US4720418A (en) * 1985-07-01 1988-01-19 Cts Corporation Pre-reacted resistor paint, and resistors made therefrom
US4753821A (en) * 1984-09-19 1988-06-28 Bayer Aktiengesellschaft Process for the partial metallization of substrate surfaces
US4808274A (en) * 1986-09-10 1989-02-28 Engelhard Corporation Metallized substrates and process for producing
US4891242A (en) * 1986-07-05 1990-01-02 Kabushiki Kaisha Toyoda Jidoshokki Seisakusho Substrate of a hybrid ic, method of forming a circuit pattern and apparatus of forming the same
US4892798A (en) * 1988-12-13 1990-01-09 Minnesota Mining And Manufacturing Company Electrophoretic imaging metal-toner fluid dispersion
US4931168A (en) * 1986-03-07 1990-06-05 Masahiro Watanabe Gas permeable electrode
US4931323A (en) * 1987-12-10 1990-06-05 Texas Instruments Incorporated Thick film copper conductor patterning by laser
US5011627A (en) * 1988-03-19 1991-04-30 Degussa Aktiengesellschaft Screen-printable paste for manufacturing electrically conductive coatings
US5091003A (en) * 1990-06-15 1992-02-25 Ford Motor Company Ink compositions and method for placing indicia on glass
US5121127A (en) * 1988-09-30 1992-06-09 Sony Corporation Microstrip antenna
US5176764A (en) * 1991-05-08 1993-01-05 The Goodyear Tire & Rubber Company Tire assembly with inner and outer tires having cooperating vent components
US5176744A (en) * 1991-08-09 1993-01-05 Microelectronics Computer & Technology Corp. Solution for direct copper writing
US5183784A (en) * 1990-02-21 1993-02-02 Johnson Matthey Inc. Silver-glass pastes
US5215820A (en) * 1990-11-30 1993-06-01 Mitsubishi Rayon Co., Ltd. Metal-electroconductive polymer composite fine particles and method for preparing same
US5216207A (en) * 1991-02-27 1993-06-01 David Sarnoff Research Center, Inc. Low temperature co-fired multilayer ceramic circuit boards with silver conductors
US5312674A (en) * 1992-07-31 1994-05-17 Hughes Aircraft Company Low-temperature-cofired-ceramic (LTCC) tape structures including cofired ferromagnetic elements, drop-in components and multi-layer transformer
US5312480A (en) * 1990-12-18 1994-05-17 Degussa Aktiengesellschaft Gold(I) mercaptocarboxylic acid esters, method of their preparation and use
US5378508A (en) * 1992-04-01 1995-01-03 Akzo Nobel N.V. Laser direct writing
US5378408A (en) * 1993-07-29 1995-01-03 E. I. Du Pont De Nemours And Company Lead-free thick film paste composition
US5384953A (en) * 1993-07-21 1995-01-31 International Business Machines Corporation Structure and a method for repairing electrical lines
US5395452A (en) * 1992-06-19 1995-03-07 Fujitsu Limited Apparatus made of silica for semiconductor device fabrication
US5403375A (en) * 1992-05-04 1995-04-04 H.C. Starck Gmbh & Co. Kg Fine-particle metal powders
US5421926A (en) * 1992-02-27 1995-06-06 Sumitomo Metal Mining Co., Ltd. Transparent conductive substrate and method of making the same
US5494550A (en) * 1993-09-07 1996-02-27 Sensormatic Electronics Corporation Methods for the making of electronic article surveillance tags and improved electronic article surveillance tags produced thereby
US5501150A (en) * 1994-07-11 1996-03-26 Agfa-Gevaert, N.V. Process for the production of a printing plate by inkjet
US5599046A (en) * 1994-06-22 1997-02-04 Scientific Games Inc. Lottery ticket structure with circuit elements
US5601638A (en) * 1994-11-21 1997-02-11 Sumitomo Metal (Smi) Electronics Devices Inc. Thick film paste
US5604027A (en) * 1995-01-03 1997-02-18 Xerox Corporation Some uses of microencapsulation for electric paper
US5604673A (en) * 1995-06-07 1997-02-18 Hughes Electronics Low temperature co-fired ceramic substrates for power converters
US5712673A (en) * 1993-12-01 1998-01-27 Dai Nippon Printing Co., Ltd. Thermal transfer recording medium and thermal transfer recording method
US5716663A (en) * 1990-02-09 1998-02-10 Toranaga Technologies Multilayer printed circuit
US5725647A (en) * 1996-11-27 1998-03-10 Minnesota Mining And Manufacturing Company Pigmented inks and humectants used therewith
US5725672A (en) * 1984-02-13 1998-03-10 Jet Process Corporation Apparatus for the high speed, low pressure gas jet deposition of conducting and dielectric thin sold films
US5746868A (en) * 1994-07-21 1998-05-05 Fujitsu Limited Method of manufacturing multilayer circuit substrate
US5747222A (en) * 1995-09-12 1998-05-05 Samsung Aerospace Industries, Ltd. Multi-layered circuit substrate and manufacturing method thereof
US5750194A (en) * 1990-03-29 1998-05-12 Vacuum Metallurgical Co., Ltd. Process for producing a metal paste
US5756008A (en) * 1996-08-14 1998-05-26 E. I. Du Pont De Nemours And Company Water cleanable silver composition
US5759712A (en) * 1997-01-06 1998-06-02 Hockaday; Robert G. Surface replica fuel cell for micro fuel cell electrical power pack
US5767810A (en) * 1995-04-24 1998-06-16 Ntt Mobile Communications Network Inc. Microstrip antenna device
US5879715A (en) * 1997-09-02 1999-03-09 Ceramem Corporation Process and system for production of inorganic nanoparticles
US5882722A (en) * 1995-07-12 1999-03-16 Partnerships Limited, Inc. Electrical conductors formed from mixtures of metal powders and metallo-organic decompositions compounds
US5894038A (en) * 1997-02-28 1999-04-13 The Whitaker Corporation Direct deposition of palladium
US5909083A (en) * 1996-02-16 1999-06-01 Dai Nippon Printing Co., Ltd. Process for producing plasma display panel
US6019926A (en) * 1997-02-20 2000-02-01 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Adminstration Reflective silvered polyimide films via in situ thermal reduction silver (I) complexes
US6025026A (en) * 1997-06-30 2000-02-15 Transitions Optical, Inc. Process for producing an adherent polymeric layer on polymeric substrates and articles produced thereby
US6027762A (en) * 1996-05-23 2000-02-22 Mitsumi Electric Co., Ltd. Method for producing flexible board
US6074725A (en) * 1997-12-10 2000-06-13 Caliper Technologies Corp. Fabrication of microfluidic circuits by printing techniques
US6080261A (en) * 1995-08-25 2000-06-27 Popat; Ghanshyam H. Adhesive image transfer technique
US6177151B1 (en) * 1999-01-27 2001-01-23 The United States Of America As Represented By The Secretary Of The Navy Matrix assisted pulsed laser evaporation direct write
US6190731B1 (en) * 1996-03-12 2001-02-20 Berhan Tecle Method for isolating ultrafine and fine particles and resulting particles
US6197147B1 (en) * 1995-12-22 2001-03-06 Hoescht Research & Technology Deutschland Gmbh & Co. Kg Process for continuous production of membrane-electrode composites
US6197366B1 (en) * 1997-05-06 2001-03-06 Takamatsu Research Laboratory Metal paste and production process of metal film
US6200405B1 (en) * 1996-07-26 2001-03-13 Taiyo Yuden Co., Ltd. Method of manufacturing laminated ceramic electronic parts
US6207268B1 (en) * 1996-11-12 2001-03-27 Dai Nippon Printing Co., Ltd. Transfer sheet, and pattern-forming method
US6214259B1 (en) * 1998-08-10 2001-04-10 Vacuum Metallurgical Co., Ltd. Dispersion containing Cu ultrafine particles individually dispersed therein
US6214520B1 (en) * 1999-01-15 2001-04-10 3M Innovative Properties Company Thermal transfer element for forming multilayer devices
US6238734B1 (en) * 1999-07-08 2001-05-29 Air Products And Chemicals, Inc. Liquid precursor mixtures for deposition of multicomponent metal containing materials
US6245494B1 (en) * 1998-08-27 2001-06-12 Agfa-Gevaert Method of imaging a heat mode recording element comprising highly dispersed metal alloys
US6251488B1 (en) * 1999-05-05 2001-06-26 Optomec Design Company Precision spray processes for direct write electronic components
US6251471B1 (en) * 1999-05-12 2001-06-26 University Of New Hampshire Surface trace electrical feedthru
US6336889B1 (en) * 1998-01-16 2002-01-08 Toyota Jidosha Kabushiki Kaisha Drive control system for hybrid vehicles
US6338809B1 (en) * 1997-02-24 2002-01-15 Superior Micropowders Llc Aerosol method and apparatus, particulate products, and electronic devices made therefrom
US6348295B1 (en) * 1999-03-26 2002-02-19 Massachusetts Institute Of Technology Methods for manufacturing electronic and electromechanical elements and devices by thin-film deposition and imaging
US6358611B1 (en) * 1996-12-19 2002-03-19 Tomoe Works Co., Ltd. Ultrafine particles comprising an organometallic core and process for the production thereof
US6358567B2 (en) * 1998-12-23 2002-03-19 The Regents Of The University Of California Colloidal spray method for low cost thin coating deposition
US6368378B2 (en) * 1999-12-22 2002-04-09 Mitsui Mining And Smelting Co., Ltd. Paste to be fired for forming circuit board and method for preparing surface-modified silver powder
US6372158B1 (en) * 1999-10-29 2002-04-16 Matsushita Electric Industrial Co., Ltd. Conductive paste
US6379745B1 (en) * 1997-02-20 2002-04-30 Parelec, Inc. Low temperature method and compositions for producing electrical conductors
US6380778B2 (en) * 2000-05-12 2002-04-30 Hitachi, Ltd. Semiconductor integrated circuit
US6379742B1 (en) * 1994-06-22 2002-04-30 Scientific Games Inc. Lottery ticket structure
US6395053B1 (en) * 1998-02-05 2002-05-28 Motorola, Inc. Method of forming metal colloids, metal colloids and method of forming a metal oxide sensitive layer for a chemical sensor device
US6399230B1 (en) * 1997-03-06 2002-06-04 Sarnoff Corporation Multilayer ceramic circuit boards with embedded resistors
US6503831B2 (en) * 1997-10-14 2003-01-07 Patterning Technologies Limited Method of forming an electronic device
US20030009726A1 (en) * 2001-07-04 2003-01-09 Industrial Technology Research Institute Method and apparatus for the formation of laminated circuit having passive componets therein
US6537359B1 (en) * 1998-03-03 2003-03-25 National Starch And Chemical Investment Holding Corporation Conductive ink or paint
US20030060038A1 (en) * 1999-12-21 2003-03-27 Plastic Logic Limited Forming interconnects
US6541433B2 (en) * 2000-07-20 2003-04-01 Beiersdorf Ag Shaped soap product comprising talc, one or more fatty acids in the form of their alkali soaps and one or more nonionic surfactants with the simultaneous absence of alkyl (oligo)glycosides
US20030083203A1 (en) * 2001-10-22 2003-05-01 Seiko Epson Corporation Apparatus and methods for forming film pattern
US20030085057A1 (en) * 2001-10-31 2003-05-08 Seiko Epson Corporation Method for forming a line pattern, line pattern, and electro-optic device
US20040038808A1 (en) * 1998-08-27 2004-02-26 Hampden-Smith Mark J. Method of producing membrane electrode assemblies for use in proton exchange membrane and direct methanol fuel cells
US6730400B1 (en) * 1999-06-15 2004-05-04 Teruo Komatsu Ultrafine composite metal particles and method for manufacturing same
US6855196B2 (en) * 2000-04-17 2005-02-15 Matsushita Electric Industrial Co., Ltd. Ink for a display panel and method for producing plasma display panel using the ink
US20050037614A1 (en) * 2003-08-15 2005-02-17 Semiconductor Energy Laboratory Co., Ltd. Method for manufacturing wiring and method for manufacturing semiconductor device
US6880909B2 (en) * 2003-04-22 2005-04-19 Lexmark International Inc. Method and apparatus for adjusting drop velocity
US6881239B2 (en) * 2001-12-21 2005-04-19 Kawatetsu Mining Co., Ltd. Ultrafine metal powder slurry with high dispersibility

Family Cites Families (258)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2785964A (en) 1953-08-17 1957-03-19 Phillips Petroleum Co Process, apparatus, and system for producing, agglomerating, and collecting carbon black
US3401020A (en) 1964-11-25 1968-09-10 Phillips Petroleum Co Process and apparatus for the production of carbon black
US3683382A (en) 1969-05-29 1972-08-08 Honeywell Inc Recording medium responsive to force fields and apparatus for recording and reproducing signals on the medium
USRE28972E (en) 1969-07-10 1976-09-21 Boehringer Ingelheim Gmbh 5-Aryl-1H-1,5-benzodiazepine-2,4-diones
US3922388A (en) 1971-03-02 1975-11-25 Honeywell Inc Method of making an encapsulated thick film resistor and associated encapsulated conductors for use in an electrical circuit
US3922355A (en) 1972-08-23 1975-11-25 Uncle Ben S Australia Pty Method of preparing colored mammary gland tissue
US3957694A (en) * 1974-09-27 1976-05-18 General Electric Company Radiation curable inks
US4094853A (en) 1975-05-15 1978-06-13 Kenrich Petrochemicals, Inc. Alkoxy titanate salts useful as coupling agents
US4051074A (en) * 1975-10-29 1977-09-27 Shoei Kagaku Kogyo Kabushiki Kaisha Resistor composition and method for its manufacture
JPS6118734B2 (en) 1976-09-07 1986-05-14 Fuji Photo Film Co Ltd
US4105483A (en) 1977-02-14 1978-08-08 Globe Industries Corporation Printing ink transfer process
US4211668A (en) 1977-03-07 1980-07-08 Thalatta, Inc. Process of microencapsulation and products thereof
US4289534A (en) 1977-05-03 1981-09-15 Graham Magnetics, Inc. Metal powder paint composition
US4463030A (en) 1979-07-30 1984-07-31 Graham Magnetics Incorporated Process for forming novel silver powder composition
US4130671A (en) 1977-09-30 1978-12-19 The United States Of America As Represented By The United States Department Of Energy Method for preparing a thick film conductor
US4419383A (en) 1979-12-26 1983-12-06 Magnavox Government And Industrial Electronics Company Method for individually encapsulating magnetic particles
US4407674A (en) 1980-03-03 1983-10-04 Ercon, Inc. Novel electroconductive compositions and powder for use therein
US4487811A (en) 1980-12-29 1984-12-11 General Electric Company Electrical conductor
US4370308A (en) 1981-05-15 1983-01-25 Cabot Corporation Production of carbon black
US4416932A (en) 1981-08-03 1983-11-22 E. I. Du Pont De Nemours And Company Thick film conductor compositions
US4388346A (en) * 1981-11-25 1983-06-14 Beggs James M Administrator Of Electrodes for solid state devices
US4418099A (en) 1982-02-05 1983-11-29 Engelhard Corporation Non-burnished precious metal composition
FR2537898B1 (en) 1982-12-21 1985-04-26 Univ Paris
US4775439A (en) 1983-07-25 1988-10-04 Amoco Corporation Method of making high metal content circuit patterns on plastic boards
JPH0461034B2 (en) 1983-09-12 1992-09-29 Canon Kk
JPH0130794B2 (en) 1984-03-16 1989-06-21 Okuno Chem Ind Co
US5049434A (en) 1984-04-30 1991-09-17 National Starch And Chemical Investment Holding Corporation Pre-patterned device substrate device-attach adhesive transfer system
US4548879A (en) 1984-05-21 1985-10-22 Rohm And Haas Company Solderable polymer thick films
US4599277A (en) 1984-10-09 1986-07-08 International Business Machines Corp. Control of the sintering of powdered metals
US4594311A (en) * 1984-10-29 1986-06-10 Kollmorgen Technologies Corporation Process for the photoselective metallization on non-conductive plastic base materials
US4697041A (en) * 1985-02-15 1987-09-29 Teijin Limited Integrated solar cells
US4859241A (en) 1986-04-16 1989-08-22 Johnson Matthey Inc. Metal flake and use thereof
US4877647A (en) 1986-04-17 1989-10-31 Kansas State University Research Foundation Method of coating substrates with solvated clusters of metal particles
US5039552A (en) 1986-05-08 1991-08-13 The Boeing Company Method of making thick film gold conductor
US4746838A (en) * 1986-07-30 1988-05-24 Telegenix, Inc. Ink for forming resistive structures and display panel containing the same
US4879104A (en) 1987-06-16 1989-11-07 Cabot Corporation Process for producing carbon black
US4948623A (en) 1987-06-30 1990-08-14 International Business Machines Corporation Method of chemical vapor deposition of copper, silver, and gold using a cyclopentadienyl/metal complex
US4857241A (en) 1987-12-10 1989-08-15 Colgate-Palmolive Company Apparatus for making post-foaming gels and method
DE3843412A1 (en) 1988-04-22 1990-06-28 Bayer Ag New polythiophene, process for their production and their use
US5132248A (en) 1988-05-31 1992-07-21 The United States Of America As Represented By The United States Department Of Energy Direct write with microelectronic circuit fabrication
US5045141A (en) 1988-07-01 1991-09-03 Amoco Corporation Method of making solderable printed circuits formed without plating
US4877451A (en) 1988-08-17 1989-10-31 Xerox Corporation Ink jet inks containing colored silica particles
WO1990007858A3 (en) 1988-12-24 1990-08-09 Technology Applic Co Ltd Improved method for making printed circuits
US5962085A (en) 1991-02-25 1999-10-05 Symetrix Corporation Misted precursor deposition apparatus and method with improved mist and mist flow
JP2538043B2 (en) 1989-04-05 1996-09-25 松下電器産業株式会社 Pattern - pattern using the same and emissions forming material - down forming method for manufacturing a substrate
GB8917078D0 (en) 1989-07-26 1989-09-13 Emi Plc Thorn An electrically conductive ink
US5028473A (en) 1989-10-02 1991-07-02 Hughes Aircraft Company Three dimensional microcircuit structure and process for fabricating the same from ceramic tape
CA2033139A1 (en) 1989-12-26 1991-06-27 Akira Shibata Silver-metal oxide composite material and process for producing the same
US5057363A (en) 1989-12-27 1991-10-15 Japan Capsular Products Inc. Magnetic display system
US5075262A (en) 1990-02-21 1991-12-24 Johnson Matthey, Inc. Silver-glass pastes
JPH03281783A (en) 1990-03-29 1991-12-12 Vacuum Metallurgical Co Ltd Formation of thin metallic film
DE69121449T2 (en) 1990-04-12 1997-02-27 Matsushita Electric Ind Co Ltd Conductive ink composition and method for producing a thick-film pattern
US5059242A (en) 1990-04-27 1991-10-22 Firmstone Michael G Seed layer compositions containing organogold and organosilver compounds
US5281261A (en) * 1990-08-31 1994-01-25 Xerox Corporation Ink compositions containing modified pigment particles
US5153023A (en) 1990-12-03 1992-10-06 Xerox Corporation Process for catalysis of electroless metal plating on plastic
US5329293A (en) 1991-04-15 1994-07-12 Trident Methods and apparatus for preventing clogging in ink jet printers
US5139818A (en) 1991-06-06 1992-08-18 General Motors Corporation Method for applying metal catalyst patterns onto ceramic for electroless copper deposition
US5539041A (en) 1991-06-11 1996-07-23 Fiberite, Inc. Siloxane and phosphazene modified cyanate resin compositions
US5244538A (en) 1991-07-26 1993-09-14 Microelectronics And Computer Technology Corporation Method of patterning metal on a substrate using direct-write deposition of a mask
US5250229A (en) 1991-10-10 1993-10-05 E. I. Du Pont De Nemours And Company Silver-rich conductor compositions for high thermal cycled and aged adhesion
FR2682625B1 (en) 1991-10-18 1997-04-11 Degussa Prod Ceramiques metal powders and metal alloys in the form of spherical and compact microcrystalline grains, and method and apparatus for manufacturing the powders.
JP3535157B2 (en) 1992-03-05 2004-06-07 キャボット コーポレイション The method of manufacturing the carbon black and the novel carbon black
US5270368A (en) 1992-07-15 1993-12-14 Videojet Systems International, Inc. Etch-resistant jet ink and process
GB9217811D0 (en) 1992-08-21 1992-10-07 Graetzel Michael Organic compounds
US5332646A (en) 1992-10-21 1994-07-26 Minnesota Mining And Manufacturing Company Method of making a colloidal palladium and/or platinum metal dispersion
US5444453A (en) 1993-02-02 1995-08-22 Ball Corporation Microstrip antenna structure having an air gap and method of constructing same
US5433893A (en) 1993-02-03 1995-07-18 Chemet Corporation Conductive compositions
EP0641670B1 (en) 1993-09-07 1996-07-31 AGFA-GEVAERT naamloze vennootschap Ink jet printing method
EP0665705B1 (en) 1993-12-30 2009-08-19 Kabushiki Kaisha Miyake Circuit-like metallic foil sheet and the like and process for producing them
US5559057A (en) 1994-03-24 1996-09-24 Starfire Electgronic Development & Marketing Ltd. Method for depositing and patterning thin films formed by fusing nanocrystalline precursors
DE19502434A1 (en) 1994-04-29 1995-11-02 Hewlett Packard Co System and method for incremental production of circuit boards
US5571311A (en) 1994-12-15 1996-11-05 Cabot Corporation Ink jet ink formulations containing carbon black products
DE69536111D1 (en) * 1994-12-15 2010-11-18 Cabot Corp With diazonium salts reacted Russ and products
EP0729189A1 (en) * 1995-02-21 1996-08-28 Interuniversitair Micro-Elektronica Centrum Vzw Method of preparing solar cells and products obtained thereof
DE69629864D1 (en) 1995-04-03 2003-10-16 Canon Kk A process for the preparation of a electron-emitting device, an electron source and an image forming apparatus
DE69622618T2 (en) 1995-04-04 2003-03-20 Canon Kk Metal-containing composition for forming an electron-emitting device and method for producing an electron-emitting device, an electron source and an image forming apparatus
US5781158A (en) 1995-04-25 1998-07-14 Young Hoek Ko Electric/magnetic microstrip antenna
US6548036B2 (en) 1995-05-04 2003-04-15 Cabot Corporation Method for producing carbon black
US5565143A (en) 1995-05-05 1996-10-15 E. I. Du Pont De Nemours And Company Water-based silver-silver chloride compositions
US6118426A (en) 1995-07-20 2000-09-12 E Ink Corporation Transducers and indicators having printed displays
US6124851A (en) 1995-07-20 2000-09-26 E Ink Corporation Electronic book with multiple page displays
JP3585598B2 (en) 1995-08-25 2004-11-04 大日本印刷株式会社 Thermal transfer sheet
JP3017422B2 (en) * 1995-09-11 2000-03-06 キヤノン株式会社 Photovoltaic element array and a manufacturing method thereof
US5679724A (en) 1995-09-29 1997-10-21 Xerox Corporation Submicron particles for ink jet inks
US5759230A (en) 1995-11-30 1998-06-02 The United States Of America As Represented By The Secretary Of The Navy Nanostructured metallic powders and films via an alcoholic solvent process
US5814683A (en) * 1995-12-06 1998-09-29 Hewlett-Packard Company Polymeric additives for the elimination of ink jet aerosol generation
US5932280A (en) 1995-12-19 1999-08-03 Ncr Corporation Printed circuit board having printed resistors and method of making printed resistors on a printed circuit board using thermal transfer techniques
US5826329A (en) 1995-12-19 1998-10-27 Ncr Corporation Method of making printed circuit board using thermal transfer techniques
US6103868A (en) 1996-12-27 2000-08-15 The Regents Of The University Of California Organically-functionalized monodisperse nanocrystals of metals
EP0910935A1 (en) 1996-06-12 1999-04-28 Brunel University Electrical circuit
US5747562A (en) * 1996-06-14 1998-05-05 Cabot Corporation Ink and coating compositions containing silicon-treated carbon black
US5837045A (en) 1996-06-17 1998-11-17 Cabot Corporation Colored pigment and aqueous compositions containing same
US5998085A (en) 1996-07-23 1999-12-07 3M Innovative Properties Process for preparing high resolution emissive arrays and corresponding articles
US5801108A (en) 1996-09-11 1998-09-01 Motorola Inc. Low temperature cofireable dielectric paste
US5874770A (en) 1996-10-10 1999-02-23 General Electric Company Flexible interconnect film including resistor and capacitor layers
DE69733393D1 (en) 1996-10-21 2005-07-07 Dainippon Printing Co Ltd Transfer layer and method for forming a pattern
US5930026A (en) 1996-10-25 1999-07-27 Massachusetts Institute Of Technology Nonemissive displays and piezoelectric power supplies therefor
US6099897A (en) 1997-01-29 2000-08-08 Mitsuboshi Belting Ltd. Method for producing metal particulate dispersion and metal particle-carrying substance
US5838271A (en) 1997-01-31 1998-11-17 Lg Semicon Co., Ltd. Digital to analog converter and bias circuit therefor for providing weighed currents
US6274412B1 (en) 1998-12-21 2001-08-14 Parelec, Inc. Material and method for printing high conductivity electrical conductors and other components on thin film transistor arrays
DE69737328T2 (en) 1997-02-20 2007-11-22 Partnerships Ltd., Inc. Low temperature process and compositions for making elektischer manager
US6109175A (en) 1997-02-21 2000-08-29 Ricoh Microelectronics Co., Ltd. Intaglio printing method, intaglio printer, method of formation of bumps or wiring pattern, apparatus therefor, bump electrode and printed circuit board
US6103393A (en) 1998-02-24 2000-08-15 Superior Micropowders Llc Metal-carbon composite powders, methods for producing powders and devices fabricated from same
US6753108B1 (en) 1998-02-24 2004-06-22 Superior Micropowders, Llc Energy devices and methods for the fabrication of energy devices
DE69819740T2 (en) * 1997-02-24 2004-09-30 Superior Micropowders Llc, Albuquerque Aerosol method and apparatus, particulate products, electronic devices and products thereof
US6660680B1 (en) 1997-02-24 2003-12-09 Superior Micropowders, Llc Electrocatalyst powders, methods for producing powders and devices fabricated from same
US6159267A (en) * 1997-02-24 2000-12-12 Superior Micropowders Llc Palladium-containing particles, method and apparatus of manufacture, palladium-containing devices made therefrom
US5846615A (en) 1997-02-28 1998-12-08 The Whitaker Corporation Direct deposition of a gold layer
US5828271A (en) 1997-03-06 1998-10-27 Northrop Grumman Corporation Planar ferrite toroid microwave phase shifter
US5837041A (en) 1997-04-15 1998-11-17 Xerox Corporation Ink cartridges having ink compositions with pigmented particles and methods for their manufacture and use
US5853470A (en) 1997-04-28 1998-12-29 Eastman Kodak Company Pigmented ink jet inks containing aldehydes
KR100274317B1 (en) 1997-08-26 2001-01-15 정명식 Fabricating method of filling up hole of chemical vapor deposition
US7115218B2 (en) 2001-06-28 2006-10-03 Parelec, Inc. Low temperature method and composition for producing electrical conductors
US6090671A (en) 1997-09-30 2000-07-18 Siemens Aktiengesellschaft Reduction of gate-induced drain leakage in semiconductor devices
JP2001518693A (en) 1997-09-30 2001-10-16 パレレック,インコーポレイテッド Manufacture of thin metal material
WO1999016556A1 (en) 1997-09-30 1999-04-08 Partnerships Limited, Inc. Method for metallizing holes
US6743319B2 (en) 1998-09-30 2004-06-01 Paralec Inc. Adhesiveless transfer lamination method and materials for producing electronic circuits
US6268014B1 (en) * 1997-10-02 2001-07-31 Chris Eberspacher Method for forming solar cell materials from particulars
DE69841544D1 (en) 1997-12-05 2010-04-22 Sumitomo Electric Industries dispersion optical fiber with flat
JPH11186572A (en) * 1997-12-22 1999-07-09 Canon Inc Photoelectromotive force element module
JP4003273B2 (en) 1998-01-19 2007-11-07 セイコーエプソン株式会社 The pattern formation method and substrate manufacturing apparatus
WO1999038176A1 (en) 1998-01-22 1999-07-29 Matsushita Electric Industrial Co., Ltd. Ink for electronic component, method for producing electronic component by using the ink for electronic component, and ink-jet device
DE69910539T2 (en) 1998-01-29 2004-06-24 Cabot Corp., Boston A process for purifying a dispersion and inkjet inks Preparation of
US6506438B2 (en) * 1998-12-15 2003-01-14 E Ink Corporation Method for printing of transistor arrays on plastic substrates
US6329899B1 (en) 1998-04-29 2001-12-11 Microcoating Technologies, Inc. Formation of thin film resistors
US6262129B1 (en) 1998-07-31 2001-07-17 International Business Machines Corporation Method for producing nanoparticles of transition metals
US6153348A (en) 1998-08-07 2000-11-28 Parelec Llc Electrostatic printing of conductors on photoresists and liquid metallic toners therefor
US6780765B2 (en) 1998-08-14 2004-08-24 Avery N. Goldstein Integrated circuit trenched features and method of producing same
US6277740B1 (en) 1998-08-14 2001-08-21 Avery N. Goldstein Integrated circuit trenched features and method of producing same
US6294401B1 (en) 1998-08-19 2001-09-25 Massachusetts Institute Of Technology Nanoparticle-based electrical, chemical, and mechanical structures and methods of making same
US6697694B2 (en) * 1998-08-26 2004-02-24 Electronic Materials, L.L.C. Apparatus and method for creating flexible circuits
EP0982090B1 (en) 1998-08-27 2003-05-02 Agfa-Gevaert Method of preparation of recording elements
JP3323887B2 (en) 1998-09-08 2002-09-09 富士ゼロックス株式会社 Ink jet printer and a printing method
US20030020768A1 (en) * 1998-09-30 2003-01-30 Renn Michael J. Direct write TM system
US6636676B1 (en) 1998-09-30 2003-10-21 Optomec Design Company Particle guidance system
DE19847161A1 (en) 1998-10-14 2000-04-20 Degussa By aerosol-doped, pyrogenically produced silicon dioxide
US6707680B2 (en) 1998-10-22 2004-03-16 Board Of Trustees Of The University Of Arkansas Surface applied passives
US20040206941A1 (en) 2000-11-22 2004-10-21 Gurin Michael H. Composition for enhancing conductivity of a carrier medium and method of use thereof
US20030151030A1 (en) 2000-11-22 2003-08-14 Gurin Michael H. Enhanced conductivity nanocomposites and method of use thereof
US6344271B1 (en) 1998-11-06 2002-02-05 Nanoenergy Corporation Materials and products using nanostructured non-stoichiometric substances
WO2000029208A1 (en) 1998-11-16 2000-05-25 Parelec Inc. Electrically heatable, transparent windows and mirrors and method for production
EP1022560B1 (en) 1999-01-21 2004-12-22 Sony International (Europe) GmbH Nanoparticle structure for use in an electronic device, especially in a chemical sensor
JP3571957B2 (en) 1999-03-30 2004-09-29 京都エレックス株式会社 Method for producing a conductive paste and a ceramic multilayer substrate
WO2000072224A1 (en) 1999-05-24 2000-11-30 Potomac Photonics, Inc. Material delivery system for miniature structure fabrication
US6811885B1 (en) 1999-06-06 2004-11-02 Agfa-Gevaert Acid stable aqueous dispersion of metal particles and applications
US6667360B1 (en) 1999-06-10 2003-12-23 Rensselaer Polytechnic Institute Nanoparticle-filled polymers
JP4948726B2 (en) * 1999-07-21 2012-06-06 イー インク コーポレイション The preferred method of fabricating an electronic circuit elements for controlling the electronic display
US6143356A (en) 1999-08-06 2000-11-07 Parelec, Inc. Diffusion barrier and adhesive for PARMOD™ application to rigid printed wiring boards
US6317023B1 (en) 1999-10-15 2001-11-13 E. I. Du Pont De Nemours And Company Method to embed passive components
KR20010070288A (en) 1999-12-09 2001-07-25 마에다 시게루 Solution containing metal component, method of and apparatus for forming thin metal film
DE60043359D1 (en) 2000-01-21 2009-12-31 Midwest Research Inst A process for the manufacture of thin-film conductors by decomposition of metal chelates in combination with metal
US6501663B1 (en) 2000-02-28 2002-12-31 Hewlett Packard Company Three-dimensional interconnect system
US6360656B2 (en) 2000-02-28 2002-03-26 Minolta Co., Ltd. Apparatus for and method of printing on three-dimensional object
US20020020491A1 (en) * 2000-04-04 2002-02-21 Price David M. High speed flip chip assembly process
WO2001082315A1 (en) 2000-04-20 2001-11-01 Parelec, Inc. Compositions and method for printing resistors, capacitors and inductors
WO2001087503A1 (en) 2000-05-12 2001-11-22 Parelec, Inc. Additive electronic circuits on thermally unstable substrates
US20030211246A1 (en) 2001-05-11 2003-11-13 Kydd Paul H. Additive electronic circuits on thermally unstable substrates
CN1217787C (en) 2000-06-30 2005-09-07 微涂技术股份有限公司 Polymer coatings
JP4035968B2 (en) 2000-06-30 2008-01-23 セイコーエプソン株式会社 A method of forming a conductive film pattern
GB0016747D0 (en) 2000-07-08 2000-08-30 Johnson Matthey Plc Ink
WO2002009884A3 (en) 2000-07-28 2002-09-19 Univ Fraser Simon Methods for the lithographic deposition of materials containing nanoparticles
US7351449B2 (en) 2000-09-22 2008-04-01 N Gimat Co. Chemical vapor deposition methods for making powders and coatings, and coatings made using these methods
JP4871443B2 (en) 2000-10-13 2012-02-08 株式会社アルバック Method of manufacturing a metal ultrafine particle dispersion liquid
JP5008216B2 (en) 2000-10-13 2012-08-22 株式会社アルバック Preparation of the inkjet ink
US6649138B2 (en) 2000-10-13 2003-11-18 Quantum Dot Corporation Surface-modified semiconductive and metallic nanoparticles having enhanced dispersibility in aqueous media
US7081214B2 (en) 2000-10-25 2006-07-25 Harima Chemicals, Inc. Electroconductive metal paste and method for production thereof
JP4677092B2 (en) 2000-12-04 2011-04-27 株式会社アルバック Electrode forming method of a flat panel display
GB0030095D0 (en) 2000-12-09 2001-01-24 Xaar Technology Ltd Method of ink jet printing
JP2004516641A (en) 2000-12-22 2004-06-03 コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィKoninklijke Philips Electronics N.V. Electrolytic emitting device and manufacturing method thereof
US6467897B1 (en) 2001-01-08 2002-10-22 3M Innovative Properties Company Energy curable inks and other compositions incorporating surface modified, nanometer-sized particles
US6599631B2 (en) 2001-01-26 2003-07-29 Nanogram Corporation Polymer-inorganic particle composites
CA2433059C (en) 2001-01-30 2009-05-12 The Procter & Gamble Company Coating compositions for modifying surfaces
US6686045B2 (en) * 2001-01-31 2004-02-03 Shin-Etsu Chemical Co., Ltd. Composite fine particles, conductive paste, and conductive film
US6875253B2 (en) * 2001-02-08 2005-04-05 Hitachi Maxell, Ltd. Metal alloy fine particles and method for producing thereof
US6830806B2 (en) 2001-04-12 2004-12-14 Kreido Laboratories Methods of manufacture of electric circuit substrates and components having multiple electric characteristics and substrates and components so manufactured
US6855367B2 (en) 2001-04-20 2005-02-15 Atsushita Electric Industrial Co., Ltd. Method of producing electronic parts, and member for production thereof
JP4328614B2 (en) 2001-06-01 2009-09-09 株式会社アルバック Micro-deposition apparatus
US20040231594A1 (en) 2001-06-01 2004-11-25 Edwards Charles O. Microdeposition apparatus
US20040173144A1 (en) 2002-05-31 2004-09-09 Edwards Charles O. Formation of printed circuit board structures using piezo microdeposition
US20030215565A1 (en) 2001-10-10 2003-11-20 Industrial Technology Research Institute Method and apparatus for the formation of laminated circuit having passive components therein
US6652967B2 (en) 2001-08-08 2003-11-25 Nanoproducts Corporation Nano-dispersed powders and methods for their manufacture
US7220370B2 (en) 2001-08-22 2007-05-22 Sumitomo Electric Industries, Ltd. Plating and production methods for producing a fine metal component using a conductive paste
CA2457847A1 (en) 2001-08-24 2003-03-06 Commonwealth Scientific And Industrial Research Organisation Functionalised nanoparticle films
CA2459235C (en) 2001-09-03 2009-11-10 Basf Aktiengesellschaft Method for increasing the whiteness of paper by means of cationic polyelectrolytes
US20060001726A1 (en) * 2001-10-05 2006-01-05 Cabot Corporation Printable conductive features and processes for making same
US7629017B2 (en) 2001-10-05 2009-12-08 Cabot Corporation Methods for the deposition of conductive electronic features
US6951666B2 (en) 2001-10-05 2005-10-04 Cabot Corporation Precursor compositions for the deposition of electrically conductive features
US20030148024A1 (en) 2001-10-05 2003-08-07 Kodas Toivo T. Low viscosity precursor compositons and methods for the depositon of conductive electronic features
EP1448725A4 (en) 2001-10-05 2008-07-23 Cabot Corp Low viscosity precursor compositions and methods for the deposition of conductive electronic features
US20030108664A1 (en) 2001-10-05 2003-06-12 Kodas Toivo T. Methods and compositions for the formation of recessed electrical features on a substrate
US7524528B2 (en) * 2001-10-05 2009-04-28 Cabot Corporation Precursor compositions and methods for the deposition of passive electrical components on a substrate
US6701605B2 (en) 2001-10-09 2004-03-09 Sonoco Development, Inc. Conductive electrical element and antenna with ink additive technology
US6936181B2 (en) 2001-10-11 2005-08-30 Kovio, Inc. Methods for patterning using liquid embossing
US20030070569A1 (en) 2001-10-11 2003-04-17 Colin Bulthaup Micro-stencil
US6562403B2 (en) 2001-10-15 2003-05-13 Kansas State University Research Foundation Synthesis of substantially monodispersed colloids
US20030073042A1 (en) 2001-10-17 2003-04-17 Cernigliaro George J. Process and materials for formation of patterned films of functional materials
KR20040077655A (en) 2001-10-19 2004-09-06 슈페리어 마이크로파우더스 엘엘씨 Tape compositions for the deposition of electronic features
JP2005507452A (en) * 2001-11-01 2005-03-17 イシウム リサーチ デベロップメント カンパニー オブ ザ ヘブリュー ユニバーシティー オブ イエルサレム Inkjet ink containing metal nanoparticles
US7553512B2 (en) 2001-11-02 2009-06-30 Cabot Corporation Method for fabricating an inorganic resistor
US20030146019A1 (en) 2001-11-22 2003-08-07 Hiroyuki Hirai Board and ink used for forming conductive pattern, and method using thereof
US6814795B2 (en) * 2001-11-27 2004-11-09 Ferro Corporation Hot melt conductor paste composition
US7674401B2 (en) 2001-12-18 2010-03-09 Asahi Kasei Kabushiki Kaisha Method of producing a thin conductive metal film
JP3803062B2 (en) 2001-12-27 2006-08-02 矢崎総業株式会社 Vehicle for the pointing device
EP1323793A1 (en) 2001-12-29 2003-07-02 Korea Advanced Institute of Science and Technology Metallic nanoparticle cluster ink and method for forming metal pattern using the same
DE10209835A1 (en) 2002-03-06 2003-10-16 Bosch Gmbh Robert Water-soluble paste and the use thereof
JP3966034B2 (en) 2002-03-14 2007-08-29 セイコーエプソン株式会社 Ejection pattern data generating method and ejection pattern data generating device
US20030185889A1 (en) 2002-03-27 2003-10-02 Jixiong Yan Colloidal nanosilver solution and method for making the same
KR20040089453A (en) 2002-03-28 2004-10-21 신꼬오덴기 고교 가부시키가이샤 Wiring structure and its manufacturing method
JP3805273B2 (en) 2002-03-29 2006-08-02 Uht株式会社 The multilayer electronic component manufacturing apparatus
DE60325033D1 (en) 2002-04-10 2009-01-15 Fujikura Ltd Conductive composition; conductive film and method of operations department of the film
JP4042497B2 (en) 2002-04-15 2008-02-06 セイコーエプソン株式会社 Method of forming a conductive layer pattern, the wiring board, an electronic device, the electronic device, as well as non-contact card medium
US6773614B2 (en) 2002-04-16 2004-08-10 Hewlett-Packard Development Company, L.P. Method of patterning conductive films
EP1383364A3 (en) 2002-05-23 2006-01-04 Nashua Corporation Circuit elements having an ink receptive coating and a conductive trace and methods of manufacture
US6827772B2 (en) 2002-05-24 2004-12-07 Cabot Corporation Carbon black and compositions containing same
CN1322075C (en) * 2002-06-13 2007-06-20 耐诺泡德斯工业有限公司 A method for the production of conductive and transparent nano-coatings and nano-inks and nano-powder coatings and inks produced thereby
US7736693B2 (en) * 2002-06-13 2010-06-15 Cima Nanotech Israel Ltd. Nano-powder-based coating and ink compositions
KR20060012545A (en) 2002-07-03 2006-02-08 나노파우더스 인더스트리어스 리미티드. Low sintering temperatures conductive nano-inks and a method for producing the same
KR100453131B1 (en) * 2002-08-10 2004-10-15 율촌화학 주식회사 Nano-sized Metals or Metal Salts Stabilized by Using Chain-end Functionalized Polymers and Their Synthetic Methods
US6890050B2 (en) 2002-08-20 2005-05-10 Palo Alto Research Center Incorporated Method for the printing of homogeneous electronic material with a multi-ejector print head
US20040058457A1 (en) 2002-08-29 2004-03-25 Xueying Huang Functionalized nanoparticles
JP2004111253A (en) 2002-09-19 2004-04-08 Asahi Glass Co Ltd Conductive composition for electrical connection of electronic device, and electron device
GB0221893D0 (en) 2002-09-20 2002-10-30 Avecia Ltd Process
JP4687107B2 (en) 2002-09-25 2011-05-25 コニカミノルタホールディングス株式会社 Electrical circuit, a thin film transistor, a manufacturing method and a manufacturing method of a thin film transistor of an electrical circuit
JP3801158B2 (en) 2002-11-19 2006-07-26 セイコーエプソン株式会社 Method of manufacturing a multilayer wiring board, a multilayer wiring board, an electronic device and electronic apparatus
CN100445096C (en) 2002-11-27 2008-12-24 株式会社爱发科 Industrial microdeposition system including masking to reduce the impact of droplet alignment and droplet volume tolerances and errors
US7914617B2 (en) 2002-11-27 2011-03-29 Tapesh Yadav Nano-engineered inks, methods for their manufacture and their applications
US7585349B2 (en) * 2002-12-09 2009-09-08 The University Of Washington Methods of nanostructure formation and shape selection
US20040126708A1 (en) 2002-12-31 2004-07-01 3M Innovative Properties Company Method for modifying the surface of a polymeric substrate
GB0300529D0 (en) 2003-01-10 2003-02-12 Qinetiq Nanomaterials Ltd Improvements in and relating to ink jet deposition
GB2412090B (en) 2003-01-10 2006-10-11 Qinetiq Nanomaterials Ltd Improvements in and relating to deposited structures
KR100614551B1 (en) 2003-01-14 2006-08-25 샤프 가부시키가이샤 Wiring Material, Wiring Substrate and Manufacturing Method Thereof, Display Panel, Fine Particle Thin Film Material, Substrate Including Thin Film Layer and Manufacturing Method Thereof
US7380690B2 (en) 2003-01-17 2008-06-03 Ricoh Company, Ltd. Solution jet type fabrication apparatus, method, solution containing fine particles, wiring pattern substrate, device substrate
WO2005044451A9 (en) 2003-10-29 2005-06-30 Conductive Inkjet Tech Ltd Electrical connection of components
US7141185B2 (en) 2003-01-29 2006-11-28 Parelec, Inc. High conductivity inks with low minimum curing temperatures
US7211205B2 (en) 2003-01-29 2007-05-01 Parelec, Inc. High conductivity inks with improved adhesion
WO2004068918A3 (en) 2003-01-31 2005-03-10 Aktina Ltd Method for producing thin silver layers
WO2004075211A1 (en) * 2003-02-20 2004-09-02 The Regents Of The University Of California Method of forming conductors at low temperatures using metallic nanocrystals and product
JP4332360B2 (en) 2003-02-28 2009-09-16 大日本印刷株式会社 Method of manufacturing a wettability pattern forming coating solution and patterned product
KR100401335B1 (en) 2003-03-08 2003-09-29 Mijitech Co Ltd Metal nanoparticle surface-coated with silicon oxides and preparation thereof
US6921626B2 (en) 2003-03-27 2005-07-26 Kodak Polychrome Graphics Llc Nanopastes as patterning compositions for electronic parts
JP2004304129A (en) 2003-04-01 2004-10-28 Seiko Epson Corp Pattern forming method by droplet discharge method, and forming method for multilevel interconnection structure
KR20030044987A (en) 2003-05-22 2003-06-09 넵테크놀로지주식회사 Manufacturing method of liquid laundry detergent with nano-sized silver colloid
JP3861854B2 (en) 2003-05-28 2006-12-27 セイコーエプソン株式会社 A method of manufacturing an electro-circuit
WO2004105985A1 (en) 2003-05-29 2004-12-09 Seagate Technology Llc Synthesis of iron-based alloy nanoparticles
US7393081B2 (en) 2003-06-30 2008-07-01 Semiconductor Energy Laboratory Co., Ltd. Droplet jetting device and method of manufacturing pattern
US20050089683A1 (en) * 2003-09-12 2005-04-28 Fuji Photo Film Co., Ltd. Magnetic particles and method of producing the same and magnetic recording medium
JP4157468B2 (en) 2003-12-12 2008-10-01 日立電線株式会社 Wiring board
KR101215119B1 (en) 2004-03-01 2012-12-24 스미토모덴키고교가부시키가이샤 Metallic colloidal solution and inkjet-use metallic ink
US7718094B2 (en) * 2004-06-18 2010-05-18 The Research Foundation Of State University Of New York Preparation of metallic nanoparticles
US20060083694A1 (en) * 2004-08-07 2006-04-20 Cabot Corporation Multi-component particles comprising inorganic nanoparticles distributed in an organic matrix and processes for making and using same
US20060115536A1 (en) * 2004-11-12 2006-06-01 Board Of Regents, The University Of Texas System Glycerin based synthesis of silver nanoparticles and nanowires
GB0427164D0 (en) 2004-12-11 2005-01-12 Eastman Kodak Co Conductive silver dispersions and uses thereof
US20060158497A1 (en) 2005-01-14 2006-07-20 Karel Vanheusden Ink-jet printing of compositionally non-uniform features
WO2006076607A1 (en) 2005-01-14 2006-07-20 Cabot Corporation Ink-jet printing of passive electricalcomponents
US7575621B2 (en) 2005-01-14 2009-08-18 Cabot Corporation Separation of metal nanoparticles
WO2006076603A3 (en) 2005-01-14 2006-11-16 Cabot Corp Printable electrical conductors
WO2006078828A3 (en) 2005-01-21 2007-01-18 Cabot Corp Method of making nanoparticulates and use of the nanoparticulates to make products using a flame reactor
US20090053400A1 (en) * 2005-02-23 2009-02-26 La Vega Fernando De Ink jet printable compositions for preparing electronic devices and patterns

Patent Citations (99)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3313632A (en) * 1962-11-27 1967-04-11 Engelhard Ind Inc Gold-silver coordination compounds and decorating compositions containing same
US3814696A (en) * 1972-06-19 1974-06-04 Eastman Kodak Co Colloidal metal in non-aqueous media
US4019188A (en) * 1975-05-12 1977-04-19 International Business Machines Corporation Micromist jet printer
US4186244A (en) * 1977-05-03 1980-01-29 Graham Magnetics Inc. Novel silver powder composition
US4266229A (en) * 1979-03-26 1981-05-05 Whittaker Corporation Light sensitive jet inks
US4255291A (en) * 1979-06-21 1981-03-10 E. I. Du Pont De Nemours And Company Air-fireable conductor composition
US4333966A (en) * 1979-07-30 1982-06-08 Graham Magnetics, Inc. Method of forming a conductive metal pattern
US4381945A (en) * 1981-08-03 1983-05-03 E. I. Du Pont De Nemours And Company Thick film conductor compositions
US4508753A (en) * 1982-08-19 1985-04-02 Gte Automatic Electric Inc. Method of producing fine line conductive/resistive patterns on an insulating coating
US4517252A (en) * 1983-05-06 1985-05-14 The Boeing Company Pre-alloyed thick film conductor for use with aluminum wire bonding and method of bonding
US5725672A (en) * 1984-02-13 1998-03-10 Jet Process Corporation Apparatus for the high speed, low pressure gas jet deposition of conducting and dielectric thin sold films
US4753821A (en) * 1984-09-19 1988-06-28 Bayer Aktiengesellschaft Process for the partial metallization of substrate surfaces
US4668533A (en) * 1985-05-10 1987-05-26 E. I. Du Pont De Nemours And Company Ink jet printing of printed circuit boards
US4720418A (en) * 1985-07-01 1988-01-19 Cts Corporation Pre-reacted resistor paint, and resistors made therefrom
US4650108A (en) * 1985-08-15 1987-03-17 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration Method for forming hermetic seals
US4931168A (en) * 1986-03-07 1990-06-05 Masahiro Watanabe Gas permeable electrode
US4891242A (en) * 1986-07-05 1990-01-02 Kabushiki Kaisha Toyoda Jidoshokki Seisakusho Substrate of a hybrid ic, method of forming a circuit pattern and apparatus of forming the same
US4808274A (en) * 1986-09-10 1989-02-28 Engelhard Corporation Metallized substrates and process for producing
US4931323A (en) * 1987-12-10 1990-06-05 Texas Instruments Incorporated Thick film copper conductor patterning by laser
US5011627A (en) * 1988-03-19 1991-04-30 Degussa Aktiengesellschaft Screen-printable paste for manufacturing electrically conductive coatings
US5121127A (en) * 1988-09-30 1992-06-09 Sony Corporation Microstrip antenna
US4892798A (en) * 1988-12-13 1990-01-09 Minnesota Mining And Manufacturing Company Electrophoretic imaging metal-toner fluid dispersion
US5716663A (en) * 1990-02-09 1998-02-10 Toranaga Technologies Multilayer printed circuit
US5183784A (en) * 1990-02-21 1993-02-02 Johnson Matthey Inc. Silver-glass pastes
US5750194A (en) * 1990-03-29 1998-05-12 Vacuum Metallurgical Co., Ltd. Process for producing a metal paste
US5091003A (en) * 1990-06-15 1992-02-25 Ford Motor Company Ink compositions and method for placing indicia on glass
US5215820A (en) * 1990-11-30 1993-06-01 Mitsubishi Rayon Co., Ltd. Metal-electroconductive polymer composite fine particles and method for preparing same
US5312480A (en) * 1990-12-18 1994-05-17 Degussa Aktiengesellschaft Gold(I) mercaptocarboxylic acid esters, method of their preparation and use
US5216207A (en) * 1991-02-27 1993-06-01 David Sarnoff Research Center, Inc. Low temperature co-fired multilayer ceramic circuit boards with silver conductors
US5176764A (en) * 1991-05-08 1993-01-05 The Goodyear Tire & Rubber Company Tire assembly with inner and outer tires having cooperating vent components
US5176744A (en) * 1991-08-09 1993-01-05 Microelectronics Computer & Technology Corp. Solution for direct copper writing
US5421926A (en) * 1992-02-27 1995-06-06 Sumitomo Metal Mining Co., Ltd. Transparent conductive substrate and method of making the same
US5378508A (en) * 1992-04-01 1995-01-03 Akzo Nobel N.V. Laser direct writing
US5403375A (en) * 1992-05-04 1995-04-04 H.C. Starck Gmbh & Co. Kg Fine-particle metal powders
US5395452A (en) * 1992-06-19 1995-03-07 Fujitsu Limited Apparatus made of silica for semiconductor device fabrication
US5312674A (en) * 1992-07-31 1994-05-17 Hughes Aircraft Company Low-temperature-cofired-ceramic (LTCC) tape structures including cofired ferromagnetic elements, drop-in components and multi-layer transformer
US5384953A (en) * 1993-07-21 1995-01-31 International Business Machines Corporation Structure and a method for repairing electrical lines
US5378408A (en) * 1993-07-29 1995-01-03 E. I. Du Pont De Nemours And Company Lead-free thick film paste composition
US5494550A (en) * 1993-09-07 1996-02-27 Sensormatic Electronics Corporation Methods for the making of electronic article surveillance tags and improved electronic article surveillance tags produced thereby
US5712673A (en) * 1993-12-01 1998-01-27 Dai Nippon Printing Co., Ltd. Thermal transfer recording medium and thermal transfer recording method
US6379742B1 (en) * 1994-06-22 2002-04-30 Scientific Games Inc. Lottery ticket structure
US5599046A (en) * 1994-06-22 1997-02-04 Scientific Games Inc. Lottery ticket structure with circuit elements
US5501150A (en) * 1994-07-11 1996-03-26 Agfa-Gevaert, N.V. Process for the production of a printing plate by inkjet
US5751325A (en) * 1994-07-11 1998-05-12 Agfa-Gevaert, N.V. Ink jet printing process
US5746868A (en) * 1994-07-21 1998-05-05 Fujitsu Limited Method of manufacturing multilayer circuit substrate
US5601638A (en) * 1994-11-21 1997-02-11 Sumitomo Metal (Smi) Electronics Devices Inc. Thick film paste
US5604027A (en) * 1995-01-03 1997-02-18 Xerox Corporation Some uses of microencapsulation for electric paper
US5767810A (en) * 1995-04-24 1998-06-16 Ntt Mobile Communications Network Inc. Microstrip antenna device
US5604673A (en) * 1995-06-07 1997-02-18 Hughes Electronics Low temperature co-fired ceramic substrates for power converters
US5882722A (en) * 1995-07-12 1999-03-16 Partnerships Limited, Inc. Electrical conductors formed from mixtures of metal powders and metallo-organic decompositions compounds
US6080261A (en) * 1995-08-25 2000-06-27 Popat; Ghanshyam H. Adhesive image transfer technique
US5747222A (en) * 1995-09-12 1998-05-05 Samsung Aerospace Industries, Ltd. Multi-layered circuit substrate and manufacturing method thereof
US6197147B1 (en) * 1995-12-22 2001-03-06 Hoescht Research & Technology Deutschland Gmbh & Co. Kg Process for continuous production of membrane-electrode composites
US5909083A (en) * 1996-02-16 1999-06-01 Dai Nippon Printing Co., Ltd. Process for producing plasma display panel
US6190731B1 (en) * 1996-03-12 2001-02-20 Berhan Tecle Method for isolating ultrafine and fine particles and resulting particles
US6027762A (en) * 1996-05-23 2000-02-22 Mitsumi Electric Co., Ltd. Method for producing flexible board
US6200405B1 (en) * 1996-07-26 2001-03-13 Taiyo Yuden Co., Ltd. Method of manufacturing laminated ceramic electronic parts
US5756008A (en) * 1996-08-14 1998-05-26 E. I. Du Pont De Nemours And Company Water cleanable silver composition
US6207268B1 (en) * 1996-11-12 2001-03-27 Dai Nippon Printing Co., Ltd. Transfer sheet, and pattern-forming method
US5725647A (en) * 1996-11-27 1998-03-10 Minnesota Mining And Manufacturing Company Pigmented inks and humectants used therewith
US6358611B1 (en) * 1996-12-19 2002-03-19 Tomoe Works Co., Ltd. Ultrafine particles comprising an organometallic core and process for the production thereof
US5759712A (en) * 1997-01-06 1998-06-02 Hockaday; Robert G. Surface replica fuel cell for micro fuel cell electrical power pack
US6379745B1 (en) * 1997-02-20 2002-04-30 Parelec, Inc. Low temperature method and compositions for producing electrical conductors
US6019926A (en) * 1997-02-20 2000-02-01 The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Adminstration Reflective silvered polyimide films via in situ thermal reduction silver (I) complexes
US6338809B1 (en) * 1997-02-24 2002-01-15 Superior Micropowders Llc Aerosol method and apparatus, particulate products, and electronic devices made therefrom
US5894038A (en) * 1997-02-28 1999-04-13 The Whitaker Corporation Direct deposition of palladium
US6399230B1 (en) * 1997-03-06 2002-06-04 Sarnoff Corporation Multilayer ceramic circuit boards with embedded resistors
US6197366B1 (en) * 1997-05-06 2001-03-06 Takamatsu Research Laboratory Metal paste and production process of metal film
US6025026A (en) * 1997-06-30 2000-02-15 Transitions Optical, Inc. Process for producing an adherent polymeric layer on polymeric substrates and articles produced thereby
US5879715A (en) * 1997-09-02 1999-03-09 Ceramem Corporation Process and system for production of inorganic nanoparticles
US6713389B2 (en) * 1997-10-14 2004-03-30 Stuart Speakman Method of forming an electronic device
US6503831B2 (en) * 1997-10-14 2003-01-07 Patterning Technologies Limited Method of forming an electronic device
US6074725A (en) * 1997-12-10 2000-06-13 Caliper Technologies Corp. Fabrication of microfluidic circuits by printing techniques
US6336889B1 (en) * 1998-01-16 2002-01-08 Toyota Jidosha Kabushiki Kaisha Drive control system for hybrid vehicles
US6395053B1 (en) * 1998-02-05 2002-05-28 Motorola, Inc. Method of forming metal colloids, metal colloids and method of forming a metal oxide sensitive layer for a chemical sensor device
US6537359B1 (en) * 1998-03-03 2003-03-25 National Starch And Chemical Investment Holding Corporation Conductive ink or paint
US6214259B1 (en) * 1998-08-10 2001-04-10 Vacuum Metallurgical Co., Ltd. Dispersion containing Cu ultrafine particles individually dispersed therein
US6245494B1 (en) * 1998-08-27 2001-06-12 Agfa-Gevaert Method of imaging a heat mode recording element comprising highly dispersed metal alloys
US20040038808A1 (en) * 1998-08-27 2004-02-26 Hampden-Smith Mark J. Method of producing membrane electrode assemblies for use in proton exchange membrane and direct methanol fuel cells
US6358567B2 (en) * 1998-12-23 2002-03-19 The Regents Of The University Of California Colloidal spray method for low cost thin coating deposition
US6214520B1 (en) * 1999-01-15 2001-04-10 3M Innovative Properties Company Thermal transfer element for forming multilayer devices
US6177151B1 (en) * 1999-01-27 2001-01-23 The United States Of America As Represented By The Secretary Of The Navy Matrix assisted pulsed laser evaporation direct write
US6348295B1 (en) * 1999-03-26 2002-02-19 Massachusetts Institute Of Technology Methods for manufacturing electronic and electromechanical elements and devices by thin-film deposition and imaging
US6251488B1 (en) * 1999-05-05 2001-06-26 Optomec Design Company Precision spray processes for direct write electronic components
US6251471B1 (en) * 1999-05-12 2001-06-26 University Of New Hampshire Surface trace electrical feedthru
US6730400B1 (en) * 1999-06-15 2004-05-04 Teruo Komatsu Ultrafine composite metal particles and method for manufacturing same
US6238734B1 (en) * 1999-07-08 2001-05-29 Air Products And Chemicals, Inc. Liquid precursor mixtures for deposition of multicomponent metal containing materials
US6372158B1 (en) * 1999-10-29 2002-04-16 Matsushita Electric Industrial Co., Ltd. Conductive paste
US20030060038A1 (en) * 1999-12-21 2003-03-27 Plastic Logic Limited Forming interconnects
US6368378B2 (en) * 1999-12-22 2002-04-09 Mitsui Mining And Smelting Co., Ltd. Paste to be fired for forming circuit board and method for preparing surface-modified silver powder
US6855196B2 (en) * 2000-04-17 2005-02-15 Matsushita Electric Industrial Co., Ltd. Ink for a display panel and method for producing plasma display panel using the ink
US6380778B2 (en) * 2000-05-12 2002-04-30 Hitachi, Ltd. Semiconductor integrated circuit
US6541433B2 (en) * 2000-07-20 2003-04-01 Beiersdorf Ag Shaped soap product comprising talc, one or more fatty acids in the form of their alkali soaps and one or more nonionic surfactants with the simultaneous absence of alkyl (oligo)glycosides
US20030009726A1 (en) * 2001-07-04 2003-01-09 Industrial Technology Research Institute Method and apparatus for the formation of laminated circuit having passive componets therein
US20030083203A1 (en) * 2001-10-22 2003-05-01 Seiko Epson Corporation Apparatus and methods for forming film pattern
US20030085057A1 (en) * 2001-10-31 2003-05-08 Seiko Epson Corporation Method for forming a line pattern, line pattern, and electro-optic device
US6881239B2 (en) * 2001-12-21 2005-04-19 Kawatetsu Mining Co., Ltd. Ultrafine metal powder slurry with high dispersibility
US6880909B2 (en) * 2003-04-22 2005-04-19 Lexmark International Inc. Method and apparatus for adjusting drop velocity
US20050037614A1 (en) * 2003-08-15 2005-02-17 Semiconductor Energy Laboratory Co., Ltd. Method for manufacturing wiring and method for manufacturing semiconductor device

Cited By (216)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070042434A1 (en) * 2003-05-14 2007-02-22 Petra Von Stein Method for identifying tff2 regulating agents and agents identified using said method
US7931941B1 (en) 2004-10-29 2011-04-26 Pchem Associates, Inc. Synthesis of metallic nanoparticle dispersions capable of sintering at low temperatures
US20100269634A1 (en) * 2005-01-14 2010-10-28 Cabot Corporation Production of metal nanoparticles
US8668848B2 (en) 2005-01-14 2014-03-11 Cabot Corporation Metal nanoparticle compositions for reflective features
US20100269635A1 (en) * 2005-01-14 2010-10-28 Cabot Corporation Production of metal nanoparticles
US8334464B2 (en) 2005-01-14 2012-12-18 Cabot Corporation Optimized multi-layer printing of electronics and displays
US8597397B2 (en) 2005-01-14 2013-12-03 Cabot Corporation Production of metal nanoparticles
US7507618B2 (en) * 2005-06-27 2009-03-24 3M Innovative Properties Company Method for making electronic devices using metal oxide nanoparticles
US20060292777A1 (en) * 2005-06-27 2006-12-28 3M Innovative Properties Company Method for making electronic devices using metal oxide nanoparticles
US9899123B2 (en) 2005-08-12 2018-02-20 Jonathan S. Alden Nanowires-based transparent conductors
US8865027B2 (en) 2005-08-12 2014-10-21 Cambrios Technologies Corporation Nanowires-based transparent conductors
US20080060549A1 (en) * 2005-08-26 2008-03-13 Ittel Steven D Preparation of silver particles using thermoplastic polymers
US7604756B2 (en) * 2005-08-26 2009-10-20 E. I. Du Pont De Nemours And Company Preparation of silver particles using thermoplastic polymers
US8430498B2 (en) 2005-09-12 2013-04-30 Electronics For Imaging, Inc. Metallic ink jet printing system and method for graphics applications
US8814346B2 (en) 2005-09-12 2014-08-26 Electronics For Imaging, Inc. Metallic ink jet printing system and method for graphics applications
US8317311B2 (en) * 2005-09-12 2012-11-27 Electronics For Imaging, Inc. Metallic ink jet printing system for graphics applications
US8740367B2 (en) 2005-09-12 2014-06-03 Electronics For Imaging, Inc. Metallic ink jet printing system for graphics applications
US20110169888A1 (en) * 2005-09-12 2011-07-14 Electronics For Imaging, Inc. Metallic ink jet printing system for graphics applications
US20090252924A1 (en) * 2005-11-04 2009-10-08 Mitsui Mining & Smelting Co., Ltd. Nickel ink and conductor film formed of nickel ink
US8486306B2 (en) * 2005-11-04 2013-07-16 Mitsui Mining & Smelting Co., Ltd. Nickel ink and conductor film formed of nickel ink
US20070144305A1 (en) * 2005-12-20 2007-06-28 Jablonski Gregory A Synthesis of Metallic Nanoparticle Dispersions
GB2436739A (en) * 2006-03-31 2007-10-03 Int Rectifier Corp Process for fabricating a semiconductor package
GB2436739B (en) * 2006-03-31 2008-03-12 Int Rectifier Corp Process for fabricating a semiconductor package
US7625637B2 (en) 2006-05-31 2009-12-01 Cabot Corporation Production of metal nanoparticles from precursors having low reduction potentials
US20070279718A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Reflective features with co-planar elements and processes for making them
US20070281099A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Solderable pads utilizing nickel and silver nanoparticle ink jet inks
US20070277685A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Process for printing features with smaller dimensions
US20070279182A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Printed resistors and processes for forming same
US20070278422A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Printable reflective features formed from multiple inks and processes for making them
US9533523B2 (en) 2006-05-31 2017-01-03 Sicpa Holding Sa Reflective features with co-planar elements and processes for making them
US20070281140A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Colored reflective features and inks and processes for making them
US20070290175A1 (en) * 2006-05-31 2007-12-20 Cabot Corporation Production of metal nanoparticles from precursors having low reduction potentials
US20070281091A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Polyimide insulative layers in multi-layered printed electronic features
US20070281136A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Ink jet printed reflective features and processes and inks for making them
US8790459B2 (en) 2006-05-31 2014-07-29 Cabot Corporation Colored reflective features and inks and processes for making them
US20070281177A1 (en) * 2006-05-31 2007-12-06 Cabot Corporation Colored Reflective Features And Inks And Processes For Making Them
US8047575B2 (en) 2006-05-31 2011-11-01 Cabot Corporation Printable features formed from multiple inks and processes for making them
US8105643B2 (en) 2006-05-31 2012-01-31 Cabot Corporation Process for printing features with smaller dimensions
US20120036702A1 (en) * 2006-05-31 2012-02-16 Cabot Corporation Printable Features Formed from Multiple Inks and Processes for Making Them
US8070186B2 (en) 2006-05-31 2011-12-06 Cabot Corporation Printable reflective features formed from multiple inks and processes for making them
US20070283848A1 (en) * 2006-06-08 2007-12-13 Samsung Electro-Mechanics Co., Ltd. Metal ink composition for inkjet printing
US20080145633A1 (en) * 2006-06-19 2008-06-19 Cabot Corporation Photovoltaic conductive features and processes for forming same
US9312404B2 (en) 2006-06-30 2016-04-12 Mitsubishi Materials Corporation Composition for manufacturing electrode of solar cell, method of manufacturing same electrode, and solar cell using electrode obtained by same method
US9620668B2 (en) 2006-06-30 2017-04-11 Mitsubishi Materials Corporation Composition for manufacturing electrode of solar cell, method of manufacturing same electrode, and solar cell using electrode obtained by same method
US8278216B1 (en) 2006-08-18 2012-10-02 Novellus Systems, Inc. Selective capping of copper
US20080145560A1 (en) * 2006-09-22 2008-06-19 Oscar Khaselev Solvent systems for metals and inks
US8597548B2 (en) 2006-09-22 2013-12-03 Alpha Metals, Inc. Solvent systems for metals and inks
WO2008036752A3 (en) * 2006-09-22 2008-06-19 Fry Metals Inc Solvent systems for metals and inks
US7453407B2 (en) 2006-12-30 2008-11-18 The Goodyear Tire & Rubber Company Antenna constructions for electronic devices and methods for manufacturing such antenna constructions
US20080158072A1 (en) * 2006-12-30 2008-07-03 Brian Matthew Logan Antenna constructions for electronic devices and methods for manufacturing such antenna constructions
US7858969B2 (en) * 2007-01-02 2010-12-28 Chunghwa Picture Tubes, Ltd. Organic thin film transistor and method for manufacturing the same
US20080157064A1 (en) * 2007-01-02 2008-07-03 Chunghwa Picture Tubes, Ltd. Organic thin film transistor and method for manufacturing the same
US20090324904A1 (en) * 2007-02-02 2009-12-31 The Regents Of The University Of California Massively Parallel Assembly of Composite Structures Using Depletion Attraction
WO2008097502A1 (en) * 2007-02-02 2008-08-14 The Regents Of The University Of California Massively parallel assembly of composite structures using depletion attraction
US9051176B2 (en) 2007-02-02 2015-06-09 The Regents Of The University Of California Massively parallel assembly of composite structures using depletion attraction
US20080199669A1 (en) * 2007-02-15 2008-08-21 Chun-Yu Lee Zinc oxide nanoparticle-containing organic-inorganic composite film, fabrication method for the same and electroluminescent element implemented by the same
US8119233B2 (en) 2007-02-17 2012-02-21 Nanogram Corporation Functional composites, functional inks and applications thereof
WO2008100568A1 (en) * 2007-02-17 2008-08-21 Nanogram Corporation Functional composites, functional inks and applications thereof
EP2131979A2 (en) * 2007-03-01 2009-12-16 Pchem Associates, Inc. Shielding based on metallic nanoparticle compositions and devices and methods thereof
EP2131979A4 (en) * 2007-03-01 2013-03-06 Pchem Associates Inc Shielding based on metallic nanoparticle compositions and devices and methods thereof
US7763362B2 (en) 2007-03-01 2010-07-27 Pchem Associates, Inc. Shielding based on metallic nanoparticle compositions and devices and methods thereof
US7751208B2 (en) 2007-03-30 2010-07-06 Cambridge Semiconductor Limited Forward power converter controllers
US7615111B2 (en) * 2007-04-18 2009-11-10 Hewlett-Packard Development Company, L.P. Metallic inkjet ink and method for forming the same
US20080257211A1 (en) * 2007-04-18 2008-10-23 Oriakhi Christopher O Metallic inkjet ink and method for forming the same
US20120308720A1 (en) * 2007-04-19 2012-12-06 Mitsubishi Materials Corporation Conductive reflective film and production method thereof
US20080259147A1 (en) * 2007-04-23 2008-10-23 Oriakhi Christopher O Intercalated compound
US7897203B2 (en) 2007-04-23 2011-03-01 Hewlett-Packard Development Company, L.P. Intercalated compound
US20080257204A1 (en) * 2007-04-23 2008-10-23 Oriakhi Christopher O Ink composition and method for forming the same
US7641728B2 (en) 2007-04-23 2010-01-05 Hewlett-Packard Development Company, L.P. Ink composition and method for forming the same
US8404160B2 (en) 2007-05-18 2013-03-26 Applied Nanotech Holdings, Inc. Metallic ink
US8058195B2 (en) 2007-06-19 2011-11-15 Cabot Corporation Nanoglass and flame spray processes for producing nanoglass
US20080318757A1 (en) * 2007-06-19 2008-12-25 Cabot Corporation Nanoglass and flame spray processes for producing nanoglass
WO2008157612A1 (en) * 2007-06-21 2008-12-24 Enthone Inc. Codeposition of copper nanoparticles in through silicon via filling
US7994640B1 (en) 2007-07-02 2011-08-09 Novellus Systems, Inc. Nanoparticle cap layer
US8039379B1 (en) * 2007-07-02 2011-10-18 Novellus Systems, Inc. Nanoparticle cap layer
US20090061169A1 (en) * 2007-07-20 2009-03-05 Oscar Khaselev Electrical conductors and methods of making and using them
US8304062B2 (en) 2007-07-20 2012-11-06 Fry's Metals, Inc. Electrical conductors and methods of making and using them
WO2009015020A1 (en) * 2007-07-20 2009-01-29 Fry's Metals, Inc. Electrical conductors and methods of making and using them
WO2009017648A1 (en) * 2007-07-26 2009-02-05 The Ex One Company, Llc Nanoparticle suspensions for use in the three-dimensional printing process
US20090069605A1 (en) * 2007-09-12 2009-03-12 Shanghai Huayi Acrylic Acid Co., Ltd. Catalyst composition and producing process thereof for use in manufacturing methacrolein
US20090096351A1 (en) * 2007-10-12 2009-04-16 Cabot Corporation Reflective layers for electronic devices
US8033715B2 (en) 2007-11-08 2011-10-11 Illinois Institute Of Technology Nanoparticle based thermal history indicators
US7867316B2 (en) * 2007-11-09 2011-01-11 Samsung Electro-Mechanics Co., Ltd. Method of manufacturing metal nanoparticles
US20090120238A1 (en) * 2007-11-09 2009-05-14 Samsung Electro-Mechanics Co., Ltd. Method of manufacturing metal nanoparticles
US8372472B2 (en) 2007-12-07 2013-02-12 Cabot Corporation Forming photovoltaic conductive features from multiple inks
US20090148978A1 (en) * 2007-12-07 2009-06-11 Cabot Corporation Processes for forming photovoltaic conductive features from multiple inks
US8101231B2 (en) 2007-12-07 2012-01-24 Cabot Corporation Processes for forming photovoltaic conductive features from multiple inks
WO2009096802A1 (en) * 2008-01-31 2009-08-06 Ydreams - Informática, S.A. Processing of electric and/or electronic elements on cellulosic material substrates
US20110149529A1 (en) * 2008-01-31 2011-06-23 Elvira Maria Correia Fortunato Processing of electric and/or electronic elements on cellulosic substrates
WO2009108304A1 (en) * 2008-02-26 2009-09-03 Cambrios Technologies Corporation Methods and compositions for ink jet deposition of conductive features
US20090223703A1 (en) * 2008-02-26 2009-09-10 Adrian Winoto Method and composition for screen printing of conductive features
US8632700B2 (en) 2008-02-26 2014-01-21 Cambrios Technologies Corporation Methods and compositions for ink jet deposition of conductive features
US20090283304A1 (en) * 2008-02-26 2009-11-19 Adrian Winoto Methods and compositions for ink jet deposition of conductive features
US8815126B2 (en) 2008-02-26 2014-08-26 Cambrios Technologies Corporation Method and composition for screen printing of conductive features
US20100015462A1 (en) * 2008-02-29 2010-01-21 Gregory Jablonski Metallic nanoparticle shielding structure and methods thereof
US20090242854A1 (en) * 2008-03-05 2009-10-01 Applied Nanotech Holdings, Inc. Additives and modifiers for solvent- and water-based metallic conductive inks
US8506849B2 (en) 2008-03-05 2013-08-13 Applied Nanotech Holdings, Inc. Additives and modifiers for solvent- and water-based metallic conductive inks
US20090230506A1 (en) * 2008-03-11 2009-09-17 Hynix Semiconductor Inc. Semiconductor device and method for fabricating the same
US7915096B2 (en) * 2008-03-11 2011-03-29 Hynix Semiconductor Inc. Semiconductor device and method for fabricating the same
US20110175192A1 (en) * 2008-03-11 2011-07-21 Hynix Semiconductor Inc. Semiconductor device and method for fabricating the same
US8373201B2 (en) 2008-03-11 2013-02-12 Hynix Semiconductor Inc. Semiconductor device and method for fabricating the same
US9333063B2 (en) 2008-05-09 2016-05-10 Boston Scientific Scimed, Inc. Antimicrobial medical devices
US20090281558A1 (en) * 2008-05-09 2009-11-12 Boston Scientific Scimed, Inc. Surgical meshes with radiopaque coatings
US20090281635A1 (en) * 2008-05-09 2009-11-12 Boston Scientific Scimed, Inc. Antimicrobial medical devices
US9427297B2 (en) 2008-05-09 2016-08-30 Boston Scientific Scimed, Inc. Surgical meshes with radiopaque coatings
US9730333B2 (en) 2008-05-15 2017-08-08 Applied Nanotech Holdings, Inc. Photo-curing process for metallic inks
US20090297829A1 (en) * 2008-06-02 2009-12-03 Bayer Materialscience Llc Process for incorporating metal nanoparticles in a polymeric article and articles made therewith
WO2010003056A1 (en) * 2008-07-02 2010-01-07 Applied Nanotech Holdings, Inc. Metallic pastes and inks
KR101610790B1 (en) 2008-07-02 2016-04-12 어플라이드 나노테크 홀딩스, 인크. Metallic pastes and inks
US20100041133A1 (en) * 2008-08-13 2010-02-18 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Biological targeting compositions and methods of using the same
US20110092961A1 (en) * 2008-08-13 2011-04-21 Searete Llc Artificial cells
US20100040546A1 (en) * 2008-08-13 2010-02-18 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Biological targeting compositions and methods of using the same
US20100042072A1 (en) * 2008-08-13 2010-02-18 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Biological targeting compositions and methods of using the same
US20140134350A1 (en) * 2008-09-15 2014-05-15 Lockheed Martin Corporation Metal nanoparticles and methods for producing and using same
US8663548B2 (en) * 2008-09-15 2014-03-04 Lockheed Martin Corporation Metal nanoparticles and methods for producing and using same
US20120100374A1 (en) * 2008-09-15 2012-04-26 Lockheed Martin Corporation Metal nanoparticles and methods for producing and using same
US20100084599A1 (en) * 2008-10-03 2010-04-08 Lewis Jennifer A Metal nanoparticle inks
US7922939B2 (en) * 2008-10-03 2011-04-12 The Board Of Trustees Of The University Of Illinois Metal nanoparticle inks
US8512417B2 (en) 2008-11-14 2013-08-20 Dune Sciences, Inc. Functionalized nanoparticles and methods of forming and using same
US20100140550A1 (en) * 2008-11-20 2010-06-10 Eos Gmbh Electro Optical Systems Method for identifying laser sintering powders
US7857998B2 (en) * 2008-11-24 2010-12-28 E. I. Du Pont De Nemours And Company High conductivity polymer thick film silver conductor composition for use in RFID and other applications
US20100127223A1 (en) * 2008-11-24 2010-05-27 E. I. Du Pont De Nemours And Company High conductivity polymer thick film silver conductor composition for use in rfid and other applications
US9247650B2 (en) 2008-12-12 2016-01-26 Tsinghua University Method for making conductive wires
US20100151120A1 (en) * 2008-12-12 2010-06-17 Tsinghua University Method for making conductive wires
US8846778B2 (en) 2008-12-22 2014-09-30 Canadian Bank Note Company, Limited Method and composition for printing tactile marks and security document formed therefrom
US20100173095A1 (en) * 2009-01-07 2010-07-08 Tsinghua University Inkjet ink and method for making conductive wires using the same
US20120020033A1 (en) * 2009-02-04 2012-01-26 Bare Conductive Ltd Skin-Safe Conductive Ink and Method for Application on the Body
US8647979B2 (en) 2009-03-27 2014-02-11 Applied Nanotech Holdings, Inc. Buffer layer to enhance photo and/or laser sintering
US9131610B2 (en) 2009-03-27 2015-09-08 Pen Inc. Buffer layer for sintering
WO2010114769A1 (en) * 2009-03-31 2010-10-07 Applied Nanotech Holdings, Inc. Metallic ink
CN102448623A (en) * 2009-03-31 2012-05-09 应用纳米技术控股股份有限公司 Metallic ink
KR101777311B1 (en) * 2009-03-31 2017-09-15 이시하라 케미칼 가부시키가이샤 Metallic ink
US20100255290A1 (en) * 2009-04-07 2010-10-07 Tsinghua University Carbon nanotube metal nanoparticle composite and method for making the same
US20100323102A1 (en) * 2009-06-23 2010-12-23 Xerox Corporation System and Method for Preparing Conductive Structures Using Radiation Curable Phase Change Gel Inks
US8422197B2 (en) 2009-07-15 2013-04-16 Applied Nanotech Holdings, Inc. Applying optical energy to nanoparticles to produce a specified nanostructure
US9072185B2 (en) 2009-07-30 2015-06-30 Lockheed Martin Corporation Copper nanoparticle application processes for low temperature printable, flexible/conformal electronics and antennas
US9797032B2 (en) 2009-07-30 2017-10-24 Lockheed Martin Corporation Articles containing copper nanoparticles and methods for production and use thereof
US9011570B2 (en) 2009-07-30 2015-04-21 Lockheed Martin Corporation Articles containing copper nanoparticles and methods for production and use thereof
US9139917B2 (en) 2009-10-16 2015-09-22 Paul Gregory O'BRIEN Transparent conductive porous nanocomposites and methods of fabrication thereof
US9138965B2 (en) 2009-10-30 2015-09-22 The Board Of Trustees Of The Leland Stanford Junior University Conductive fibrous materials
US20110200873A1 (en) * 2009-10-30 2011-08-18 Liangbing Hu Conductive fibrous materials
WO2011053811A1 (en) * 2009-10-30 2011-05-05 The Board Of Trustees Of The Leland Stanford Junior University Conductive fibrous materials
US20110115086A1 (en) * 2009-11-13 2011-05-19 Xerox Corporation Metal nonoparticle compositions
US9603260B2 (en) 2009-11-13 2017-03-21 Teknologian Tutkimuskeskus Vtt Oy Method and products related to deposited particles
US8808789B2 (en) * 2009-11-13 2014-08-19 Xerox Corporation Process for forming conductive features
US9378861B2 (en) 2009-11-30 2016-06-28 Lockheed Martin Corporation Nanoparticle composition and methods of making the same
US20110215279A1 (en) * 2010-03-04 2011-09-08 Lockheed Martin Corporation Compositions containing tin nanoparticles and methods for use thereof
US8834747B2 (en) 2010-03-04 2014-09-16 Lockheed Martin Corporation Compositions containing tin nanoparticles and methods for use thereof
US8733923B2 (en) 2010-03-17 2014-05-27 Seiko Epson Corporation Printing device and printing method
US8529009B2 (en) 2010-03-17 2013-09-10 Seiko Epson Corporation Printing device and printing method
EP2366551A3 (en) * 2010-03-17 2012-02-01 Seiko Epson Corporation Printing device and printing method
CN102189788A (en) * 2010-03-17 2011-09-21 精工爱普生株式会社 Printing device and printing method
US20110227984A1 (en) * 2010-03-17 2011-09-22 Seiko Epson Corporation Printing device and printing method
US8383014B2 (en) 2010-06-15 2013-02-26 Cabot Corporation Metal nanoparticle compositions
US20120034156A1 (en) * 2010-08-03 2012-02-09 Searete Llc, A Limited Liability Corporation Of The State Of Delaware Artificial cells
US8158032B2 (en) * 2010-08-20 2012-04-17 Xerox Corporation Silver nanoparticle ink composition for highly conductive features with enhanced mechanical properties
US9088071B2 (en) 2010-11-22 2015-07-21 ChamTech Technologies, Incorporated Techniques for conductive particle based material used for at least one of propagation, emission and absorption of electromagnetic radiation
US9954276B2 (en) 2010-11-22 2018-04-24 Ncap Licensing, Llc Techniques for conductive particle based material used for at least one of propagation, emission and absorption of electromagnetic radiation
WO2012075394A1 (en) * 2010-12-02 2012-06-07 Applied Nanotech Holdings, Inc. Nanoparticle inks for solar cells
US20130222496A1 (en) * 2010-12-23 2013-08-29 Hewlett-Packard Development Company, L.P. Optically clear fluid composition
US9328249B2 (en) * 2010-12-23 2016-05-03 Hewlett-Packard Development Company, L.P. Optically clear fluid composition
US8623938B2 (en) 2010-12-31 2014-01-07 Tsinghua University Inkjet ink and method for making the same
US8647535B2 (en) * 2011-01-07 2014-02-11 International Business Machines Corporation Conductive metal and diffusion barrier seed compositions, and methods of use in semiconductor and interlevel dielectric substrates
US20120178241A1 (en) * 2011-01-07 2012-07-12 International Business Machines Corporation Conductive metal and diffusion barrier seed compositions, and methods of use in semiconductor and interlevel dielectric substrates
US8735284B2 (en) 2011-01-07 2014-05-27 International Business Machines Corporation Conductive metal and diffusion barrier seed compositions, and methods of use in semiconductor and interlevel dielectric substrates
US9759848B2 (en) 2011-01-17 2017-09-12 University Of Utah Research Foundation Methods, systems, and apparatus for reducing the frequency and/or severity of photophobic responses or for modulating circadian cycles
US9606277B2 (en) 2011-01-17 2017-03-28 University Of Utah Research Foundation Apparatus and methods for reducing frequency or severity of photophobic responses or modulating circadian cycles
US9764157B2 (en) 2011-01-17 2017-09-19 University Of Utah Research Foundation Methods, systems, and apparatus for reducing the frequency and/or severity of photophobic responses or for modulating circadian cycles
WO2012105310A1 (en) * 2011-02-02 2012-08-09 コニカミノルタホールディングス株式会社 Organic electroluminescence element and illumination device
JP5900351B2 (en) * 2011-02-02 2016-04-06 コニカミノルタ株式会社 Method of manufacturing an organic electroluminescence element
US20130305943A1 (en) * 2011-02-08 2013-11-21 Lg Chem, Ltd. Ink composition for printing, and printing method using same
CN103430241A (en) * 2011-02-28 2013-12-04 无限科技全球公司 Metallic nanofiber ink, substantially transparent conductor, and fabrication method
US9196760B2 (en) 2011-04-08 2015-11-24 Ut-Battelle, Llc Methods for producing complex films, and films produced thereby
US20120279766A1 (en) * 2011-05-06 2012-11-08 Xerox Corporation Method of fabricating high-resolution features
CN102776507A (en) * 2011-05-06 2012-11-14 施乐公司 Method of fabricating high-resolution features, compound and electric conduction features
US8586134B2 (en) * 2011-05-06 2013-11-19 Xerox Corporation Method of fabricating high-resolution features
US9231212B2 (en) 2011-05-23 2016-01-05 Koninklijke Philips N.V. Fabrication apparatus for fabricating a layer structure
US9472787B2 (en) 2011-05-23 2016-10-18 Oledworks Gmbh Fabrication apparatus for fabricating a patterned layer
US20120319152A1 (en) * 2011-06-14 2012-12-20 Won Hwa Park Light emitting device package
US8912560B2 (en) * 2011-06-14 2014-12-16 Lg Innotek Co., Ltd. Light emitting device package
US8499445B1 (en) * 2011-07-18 2013-08-06 Endicott Interconnect Technologies, Inc. Method of forming an electrically conductive printed line
KR101860603B1 (en) 2011-09-06 2018-05-23 헨켈 아이피 앤드 홀딩 게엠베하 Conductive material and process
CN103975030A (en) * 2011-09-06 2014-08-06 汉高知识产权控股有限责任公司 Conductive material and process
US20140174801A1 (en) * 2011-09-06 2014-06-26 Henkel IP & Holding GmbH Conductive material and process
US20140178601A1 (en) * 2011-09-06 2014-06-26 Henkel IP & Holding GmbH Conductive material and process
WO2013036523A1 (en) * 2011-09-06 2013-03-14 Henkel Corporation Conductive material and process
JP2014529674A (en) * 2011-09-06 2014-11-13 ヘンケル アイピー アンド ホールディング ゲゼルシャフト ミット ベシュレンクテル ハフツング Conductive materials and processes
US20140197354A1 (en) * 2011-09-11 2014-07-17 Acta Technology Inc. Method of making nanaofluids for ground souce heat pumps and other applications
US20130062555A1 (en) * 2011-09-11 2013-03-14 Acta Technology Inc Nanofluids and a method of making nanofluids for ground source heat pumps and other applications
US8580138B2 (en) * 2011-09-11 2013-11-12 Acta Technology Inc Nanofluids and a method of making nanofluids for ground source heat pumps and other applications
US20150056426A1 (en) * 2012-02-29 2015-02-26 Yisum Research Development Company Of The Hebrew University Of Jerusalem Ltd. Inks containing metal precursors nanoparticles
US20140072720A1 (en) * 2012-05-22 2014-03-13 University Of Massachusetts Patterned nanoparticle structures
US20150191611A1 (en) * 2012-06-19 2015-07-09 Chameleon Innovations Australia (Cia) Pty Ltd Composition
US9714351B2 (en) * 2012-06-19 2017-07-25 Chameleon Innovations Australia (Cia) Pty Ltd Composition
WO2014011578A1 (en) * 2012-07-09 2014-01-16 Applied Nanotech Holdings, Inc. Photosintering of micron-sized copper particles
US9598776B2 (en) 2012-07-09 2017-03-21 Pen Inc. Photosintering of micron-sized copper particles
WO2014028280A3 (en) * 2012-08-16 2014-05-15 Nthdegree Technologies Worldwide Inc. Conductive, metallic and semiconductor ink compositions
WO2014028280A2 (en) * 2012-08-16 2014-02-20 Nthdegree Technologies Worldwide Inc. Conductive, metallic and semiconductor ink compositions
US20160281229A1 (en) * 2012-11-29 2016-09-29 Lg Chem, Ltd. Gas barrier film with protective coating layer containing inorganic particles
EP2930722A4 (en) * 2012-12-07 2015-12-09 Fujifilm Corp Process for manufacturing conductive film and printed wiring board
US20140262443A1 (en) * 2013-03-14 2014-09-18 Cambrios Technologies Corporation Hybrid patterned nanostructure transparent conductors
US8968824B2 (en) * 2013-03-14 2015-03-03 Dowa Electronics Materials Co., Ltd. Method for producing silver conductive film
US20140287159A1 (en) * 2013-03-21 2014-09-25 Intrinsiq Materials, Inc. Conductive paste formulations for improving adhesion to plastic substrates
US20140356524A1 (en) * 2013-05-31 2014-12-04 Basf Corporation Nanostructure Dispersions And Transparent Conductors
US9318230B2 (en) * 2013-05-31 2016-04-19 Basf Corporation Nanostructure dispersions and transparent conductors
US20160118156A1 (en) * 2013-06-07 2016-04-28 Seiko Pmc Corporation Metal nanowire-containing composition
US20150034996A1 (en) * 2013-08-01 2015-02-05 Epistar Corporation Light-emitting device
US20150069649A1 (en) * 2013-09-12 2015-03-12 The Exone Company Powder Particle Layerwise Three-Dimensional Printing Process
US20150125624A1 (en) *