C3nano Inc.

Ekc Technology Inc.

Ajay Virkar

Xiqiang Yang

Ying-Syi Li

Yongxing Hu

Hua Gu

Xiaofeng Chen

Christopher Steven Scully

Steven Michael Lam

Arthur Yung-Chi Cheng

Alex Da Zhang Tan

Yadong Cao

Yu Kambe

Melburne C LeMieux

Melanie Mariko Inouye

Alexander Seung-il Hong

Jing Shun Ang

Melanie Maniko Inouye

Faraz Azadi Manzour

Dennis R McKean

Peikang Liu

Nazim Uddin

Dennis Mckean

Yung-Yu Huang

Yungyu Huang

Authur Yung-Chi Cheng

Chris Scully

Byunghwan Kang

Jackie Chen

Vicki Luo

Clifford M Morris

Andrew Hyeongjoo Moon

Melburne C Lemieux

Reduction/oxidation reagents have been found to be effective to chemically cure a sparse metal nanowire film into a fused metal nanostructured network through evidently a ripening type process. The resulting fused network can provide desirable low sheet resistances while maintaining good optical transparency. The transparent conductive films can be effectively applied as a single conductive ink or through sequential forming of a metal nanowire film with the subsequent addition of a fusing agent. The fused metal nanowire films can be effectively patterned, and the patterned films can be useful in devices, such as touch sensors.

Fused metal nanostructured networks, fusing solutions with reducing agents and methods for forming metal networks

Composite materials with noble metal coated silver nanowires loaded into polymer are described. The composite materials may have resistivities of no more than about 100 Ohm-cm, or from about 100 Ohm-cm to about 1×10Ohm-cm depending on the amount of noble metal coated silver nanowires loaded into the polymer. The noble metal coated silver nanowires may be platinum coated silver nanowires. Metal particulates such as silver flakes or silver particles may be added to the composite materials in order to obtain desired properties. Composite precursor compositions and methods for preparing the composite materials are described.

Silver nanowire and noble-metal coated silver nanowire conductive polymer composites with low loading percolation conduction

Nanoscale colorants are introduced to adjust the hue of transparent conductive films, such as to provide a whiter film. The transparent conductive films can have sparse metal conductive layers, which can be formed using silver nanowires. Color of the film can be evaluated using standard color parameters. In particular, values of color parameter b* can be reduced with the nanoscale colorants without unacceptably changing other parameters, such as haze, a* and transparency.

Transparent films with control of light hue using nanoscale colorants

Methods for processing deposited metal nanowire inks with metal ions are used to form fused metal nanostructured networks. The metal nanowire inks include a hydrophilic polymer binder, such as a cellulose based binder. The metal nanowire inks can be deposited onto a substrate surface and dried to drive the fusing process. Transparent conductive films can be formed with desirable properties.

Method for processing metal nanowire ink with metal ions

Metal nanowires, such as silver nanowires coated on a substrate were sintered together to form fused metal nanowire networks that have greatly improved conductivity while maintaining good transparency and low haze. The method of forming such a fused metal nanowire networks are disclosed that involves exposure of metal nanowires to various fusing agents on a short timescale. The resulting sintered network can have a core-shell structure in which metal halide forms the shell. Additionally, effective methods are described for forming patterned structure with areas of sintered metal nanowire network with high conductivity and areas of un-sintered metal nanowires with low conductivity. The corresponding patterned films are also described. When formed into a film, materials comprising the metal nanowire network demonstrate low sheet resistance while maintaining desirably high levels of optical transparency with low haze, making them suitable for transparent electrode, touch sensors, and other electronic/optical device formation.

Metal nanostructured networks and transparent conductive material

A method of forming a transparent electrically conductive film including depositing a dispersion of metal nanowires onto a substrate surface, delivering a solution including a fusing agent in a solvent onto the substrate surface, and drying the substrate surface after depositing the metal nanowires and delivering the fusing agent solution to fuse at least some of the metal nanowires into the transparent electrically conductive film comprising a fused metal nanowire network.

Metal nanowire networks and transparent conductive material

Structures are described having thin flexible polymer substrates with electrically conductive films on each opposing surface while having high optical transmittance and good optical properties. The structures can have total thicknesses of no more than about 30 microns and good flexibility. Processing approaches are described that allow for the coating of the very thin structures by providing support through the coating process. The structures are demonstrated to have good durability under conditions designed to test accelerated wear for touch sensor use.

Thin flexible structures with surfaces with transparent conductive films and processes for forming the structures

Highly uniform and thin silver nanowires are described having average diameters below 20 nm and a small standard deviation of the diameters. The silver nanowires have a high aspect ratio. The silver nanowires can be characterized by a small number of nanowires having a diameter greater than 18 nm as well as with a blue shifted narrow absorption spectrum in a dilute solution. Methods are described to allow for the synthesis of the narrow uniform silver nanowires. Transparent conductive films formed from the thin, uniform silver nanowires can have very low levels of haze and low values of ΔL*, the diffusive luminosity, such that the transparent conductive films can provide little alteration of the appearance of a black background.

Thin and uniform silver nanowires, method of synthesis and transparent conductive films formed from the nanowires

Transparent conductive films comprising sparse metal conductive layers are processed after coating with an overcoat to lower the sheet resistance of the film. The sparse metal conductive layer can comprise a fused metal nanostructured network. A coating, such as a polymer overcoat or a polymer undercoat can noble metal ions that can further reduce the sheet resistance with the application of heat and optionally humidity. In particular, silver ions in a coating are demonstrated to provide important stabilization of sparse metal conductive layers, whether or not fused, upon the application of heat and humidity. A coating can further comprise a metal salt stabilization composition.

Coatings and processing of transparent conductive films for stabilization of sparse metal conductive layers

Fusing nanowire inks are described that can also comprise a hydrophilic polymer binder, such as a cellulose based binder. The fusing nanowire inks can be deposited onto a substrate surface and dried to drive the fusing process. Transparent conductive films can be formed with desirable properties.

Metal nanowire ink for the formation of transparent conductive films with fused networks

Metal salt based stabilizers are described that are effective to improve stability of sparse metal conductive films formed with metal nanowires, especially silver nanowires. Specifically, vanadium (+5) compositions can be effectively placed in coatings to provide desirable stabilization under accelerated wear testing conditions. Sparse metal conductive films can comprise fused metal nanostructured networks. Cobalt (+2) compounds can be incorporated as stabilization agents within nanowire inks to provide a high degree of stabilization without significantly interfering with the fusing process.

Stabilized sparse metal conductive films and solutions for delivery of stabilizing compounds

Metal nanowires with uniform noble metal coatings are described. Two methods, galvanic exchange and direct deposition, are disclosed for the successful formation of the uniform noble metal coatings. Both the galvanic exchange reaction and the direct deposition method benefit from the inclusion of appropriately strong binding ligands to control or mediate the coating process to provide for the formation of a uniform coating. The noble metal coated nanowires are effective for the production of stable transparent conductive films, which may comprise a fused metal nanostructured network.

Noble metal coated silver nanowires, methods for performing the coating

Metal nanowire ink and method for forming conductive film

Desirable methods for larger scale silver nanoplate synthesis are described along with methods for applying a noble metal coating onto the silver nanoplates to form coated silver nanoplates with a desirable absorption spectrum. The silver nanoplates are suitable for use in coatings for altering the hue of a transparent film. The hue adjustment can be particularly desirable for transparent conductive films.

Methods for synthesizing silver nanoplates and noble metal coated silver nanoplates and their use in transparent films for control of light hue

A formable transparent conductive film are described that comprise a sparse metal conductive layer, a thermoplastic polymer substrate supporting the sparse metal conductive layer, a viscoelastic polymer with a thickness from about 15 microns to about 150 microns over the sparse metal conductive layer. A layered film structure can be formed that is suitable for contouring on the surface of a three dimensional object without unacceptable increases in sheet resistance and with good optical transparency and low haze. The formable films can be placed into a frozen configuration bent 90 degrees with a radius of curvature of no more than about 5 centimeters while exhibiting a surface resistance of no more than about 500 ohms/sq. with a total transmittance with respect to visible light of at least about 80%.

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San Mateo, CA, United States of America

Ajay Virkar