Curable carbon nanotube ink and transparent conductive film prepared using the ink

Abstract

To provide a carbon nanotube ink and a transparent conductive film prepared using the ink, characterized by maintaining excellent conductivity, high visible light transmittance, and low haze.SOLUTION: A curable carbon nanotube ink includes a curable resin binder, a catalyst that is configured to be activated and cure the resin binder, a viscous-to-vapor diluent, and carbon nanotubes (CNTs). The CNT concentration range in the ink is from about 0.001 wt.% to about 0.2 wt.%.SELECTED DRAWING: None

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to Provisional Application No. 63 / 090,956, filed October 13, 2020, the entire disclosure of which is incorporated herein by reference for all purposes. [Background technology]

[0002] The present disclosure relates to curable conductive coatings. Carbon nanotube inks (i.e., conductive coatings) can be used as part of transparent conductive films (TCFs). Summary of the Invention

[0003] The present invention includes a curable carbon nanotube (CNT) ink (i.e., a printable conductive coating) and a transparent conductive film (TCF) made (e.g., printed) with the ink. The ink contributes to both the electrical conductivity of the film and its resistance to environmental conditions. The ink also functions as an etch mask. The ink includes one or both of a radiation curable resin and a heat curable resin, which when cured, acts as a binder for the CNTs and also promotes good adhesion, abrasion resistance, and chemical resistance. A catalyst facilitates the curing of the resin. The ink also includes a viscous diluent that evaporates completely during the ink drying / curing process. The diluent helps achieve a desired viscosity of the ink that allows the ink to be coated onto an underlying substrate, such as by screen printing. In some embodiments, the ink has a viscosity of about 1,000 cP to about 50,000 cP. In some embodiments, the curable carbon nanotube ink is comprised of a single-walled carbon nanotube component and a UV and / or heat curable polymer binder component. CNT ink is a screen printable ink that does not contain surfactant. Generally, CNTs need a surfactant to remain dispersed or they may agglomerate. When a coating containing surfactant is printed or dried, the surfactant must be washed away. If not washed away, the electronic properties of the CNT layer will be significantly worse. In this case, the V2V diluent is viscous enough (has rheology) so that the CNTs do not find / contact each other, so they do not agglomerate. The diluent is then completely dried, creating a conductive coating from the ink, without the need to wash away the surfactant.

[0004] The ink can be used to create a TCF. The TCF includes a substrate, a metal nanowire coating or metal mesh (MM) layer on the substrate surface, and an ink on the nanowire or MM layer. After the ink is cured, the resulting multilayer structure exhibits excellent electrical conductivity, high visible light transmittance, and excellent adhesion of the metal nanowire (or metal mesh) / CNT composite structure to the substrate. In some examples, the TCF also includes a substrate (polymer film, glass panel, etc.) without a metal nanowire or metal mesh coating with the printed CNT ink.

[0005] The present invention results in the creation of novel curable carbon nanotube inks and printed films that exhibit the advantages of good adhesion to the metal nanowire coating or metal mesh layer, improved abrasion resistance, and good solvent and chemical resistance during the etching process, while maintaining excellent electrical conductivity, high visible light transmission, and low haze compared to TCFs made with non-curable CNT inks.

[0006] All embodiments and features described below can be combined in any way that is technically possible.

[0007] In one embodiment, the curable carbon nanotube ink includes a curable resin binder, a catalyst configured to be activated to cure the resin binder, a viscous-evaporative diluent, and carbon nanotubes (CNTs). The CNT concentration in the ink ranges from about 0.001% to about 0.2% by weight.

[0008] Some embodiments include one or a combination of the above and / or below features. In one embodiment, the resin binder concentration range in the ink is about 0.1% to about 5% by weight. In one embodiment, the catalyst concentration range in the ink is about 0.001% to about 1.0% by weight. In one embodiment, the diluent concentration range in the ink is about 90% to about 99% by weight. In one embodiment, the curable carbon nanotube ink further includes a filler resin having a concentration range in the ink of about 0.1% to about 5% by weight. In one embodiment, the resin binder includes a mixture of a UV curable resin and a thermosetting resin. In one embodiment, the curable carbon nanotube ink has a viscosity of about 1,000 cP to about 50,000 cP. In one embodiment, the CNTs include single-walled CNTs.

[0009] Some embodiments include one or a combination of the above and / or below features. In one embodiment, the resin binder is radiation curable. In one embodiment, the resin binder includes one or more of a UV curable multifunctional acrylic copolymer, a UV curable urethane polymer, or a UV curable polyester. In one embodiment, the curable carbon nanotube ink further includes one or more of a non-UV curable resin, a multifunctional oligomer, or a monomer. In one embodiment, the catalyst includes a Type I or Type II free radical photoinitiator. In one embodiment, the resin binder is thermally curable. In one embodiment, the resin binder includes one or more of an acrylic copolymer, a urethane polymer, or a polyester with acid functionality. In one embodiment, the catalyst includes at least one of a polyaziridine crosslinker, a polycarbodiimide crosslinker, or a peroxide type catalyst.

[0010] In another embodiment, a transparent conductive film (TCF) includes a polymer film substrate, a metal nanowire or metal mesh layer on a surface of the film, and a cured carbon nanotube (CNT) ink covering at least a portion of the metal nanowire or metal mesh layer. The CNT ink includes a curable resin binder, a catalyst configured to be activated to cure the resin binder, a viscous-evaporative diluent, and CNTs. The CNT concentration range in the ink is about 0.001% to about 0.2% by weight.

[0011] Some embodiments include one or a combination of the above and / or following features. In one embodiment, the TCF exhibits good electrical conductivity, high visible light transmission, and good adhesion of the metal nanowire or metal mesh layer and the cured CNT ink to the substrate. In one embodiment, the TCF exhibits good adhesion to the metal nanowire or metal mesh layer, improved abrasion resistance, and good solvent and chemical resistance during the etching process compared to TCFs made with uncured CNT inks. In one embodiment, the TCF maintains good electrical conductivity, high visible light transmission, and low haze. [Brief description of the drawings]

[0012] Various aspects of at least one embodiment are described below with reference to the accompanying drawings, which are not intended to be drawn to scale. The drawings are included to provide explanation and further understanding of the various aspects and embodiments, and are incorporated in and constitute a part of this specification, but are not intended to define the boundaries of the invention. In the drawings, identical or nearly identical components shown in various figures may be designated with similar reference numerals. For clarity, not all components are shown in each figure.

[0013] [Figure 1] FIG. 2 is a schematic side view of the TCF. [Figure 2A] This shows how to create a TCF. [Figure 2B] This shows how to create a TCF. [Figure 2C] This shows how to create a TCF. [Figure 2D] This shows how to create a TCF. [Diagram 3] The steps in the TCF creation process are shown below. [Figure 4] 1 is a graph showing ink viscosity for different levels of CNT. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The system, method and apparatus embodiments discussed herein are not limited in application to the details of construction and the arrangement of components set forth in the following description or illustrated in the accompanying drawings. The systems, methods and apparatus may be implemented in other embodiments and may be practiced or carried out in various ways. The specific embodiments are provided herein for purposes of illustration only and are not intended to be limiting. In particular, functions, components, elements and features discussed in connection with any one or more embodiments are not intended to be excluded from a similar role in other embodiments.

[0015] The embodiments disclosed herein can be combined with other embodiments in any manner consistent with at least one of the principles disclosed herein, and references to "embodiments," "some embodiments," "alternative embodiments," "various embodiments," "an embodiment," etc. are not necessarily mutually exclusive and are intended to indicate that a particular feature, structure, or characteristic described may be included in at least one embodiment. Appearances of such terms in this specification do not necessarily all refer to the same embodiment.

[0016] Additionally, the phraseology and terms used herein are for purposes of explanation and should not be considered limiting. Any reference to computer program products, systems and methods examples, components, acts, or features referred to herein in the singular may also encompass embodiments including the plural, and any reference to any example, component, element, act, or feature referred to herein in the plural may also encompass examples including only the singular. Thus, singular or plural references are not intended to limit the presently disclosed systems or methods, their components, acts, or elements. Use of "including," "comprising," "having," "containing," "involving," and variations thereof herein is intended to encompass the items listed thereafter and equivalents thereof, as well as additional items. References to "or" may be interpreted inclusively, such that any term described with "or" may refer to either a single term, multiple terms, and all terms listed.

[0017] CNT inks can be printed on flexible and rigid substrates. Substrates may be inorganic and / or organic, including but not limited to glass, silicon wafers, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), thermoplastic polyurethane (TPU), cyclic olefin polymer (COP), silicone, or polyimide (CPI) plastic films. Plastic substrates may have a primer layer or have a surface treatment to improve surface tension (e.g., corona treatment, flame treatment, other plasma, etc.), and in some examples, the film thickness ranges from 12.5 microns to 300 microns.

[0018] The substrate, nanowire layer (e.g., silver nanowire (AgNW) or metal mesh (MM) layer), and method of manufacturing the TCF according to the present disclosure may be of the type disclosed in International Patent Application Publication No. WO2016 / 172315 and / or International Patent Application Publication No. WO2020 / 102392, the entire disclosures of which are incorporated herein by reference for all purposes.

[0019] In some embodiments, the TCF is prepared by the following procedure.

[0020] Preparation of coating solution: Curable CNT ink: UV-curable CNT ink: UV CNT ink formulations consist of a viscous-to-evaporative ("V2V") diluent that evaporates completely during the ink drying / curing process, a CNT dispersion in alcohol and amine, a radiation curable resin binder, a photoinitiator, and optionally a non-UV curable resin that is added to the UV resin mixture. In some examples, the CNT concentration ranges from 0.01 to 2.0 g / L (i.e., from about 0.001 wt % to about 0.2 wt % in the ink). In some examples, the CNT to UV resin or resin mixture binder concentration ratio (CNT / binder) ranges from about 1:1 to about 1:1200.

[0021] The V2V diluent helps to achieve a desired viscosity of the ink that can be coated onto an underlying substrate, such as by screen printing, etc. In some examples, the V2V diluent is of the type disclosed in U.S. Patent Nos. 9,777,167 and 9,777,168, the entire disclosures of which are incorporated herein by reference for all purposes.

[0022] In some embodiments, UV resin binders include, but are not limited to: 1. Multifunctional UV-curable oligomers and monomers, such as Ebecryl 4859, Ebecryl 4858, Ebecryl 8701, Ebecryl 8605, Ebecryl 225, Ebecryl 4740, Ebecryl 4859, Ebecryl 8405, Ebecryl 1290, Ebecryl 4738, Ebecryl 4513, Ebecryl 284 from Allnex, SR 399, SR368, CN 9210, CN 9276, CN 9196, CN 9209, CN 2306 from Sartomer, Miramer M140, Miramer M150, Miramer M1182, Miramer M200, Miramer M 262, Miramer M from MIWON; 300, Miramer M 3130, Miramer M 420. Miramer PU 610, Miramer PU6510, Miramer PU5000, Miramer PU640, Miramer Sc2100, Miramer SC2152, Miramer MU 9500. 2. Multifunctional UV curable acrylic copolymers, NeoRad-A 20 from DSM, Ebecryl 4654 from Allnex, Lumicryl U-721S, Lumicryl 102, Lumicryl 2882, Lumicryl 245 from Enstron.

[0023] In some examples, UV photoinitiators include, but are not limited to, Irgacure 651, Irgacure 369, Irgacure 901, Irgacure 184, Irgacure 2959, Irgacure TPO, Irgacure 819, Darocur 1173 from BASF, Omnirad 500, Esacure kip 160, Esacure kip 100F, Esacure kip 150, Esacure TZT, Esacure 3644, Esacure 1001M, Omnirad 4-PBZ, Omnirad BP from IGM.

[0024] In some examples, non-UV curable (i.e. non-hardening) resin binders, if used, include Neocryl 819, Neocryl 817, Neocryl 890, and Neocryl 813 manufactured by DSM, and Joncryl 857, Joncryl 586, Joncryl 611, Joncryl 678, Joncryl 680, Joncryl 682, Joncryl 683, Joncryl 693, Joncryl ECO 675, Joncryl ECO 684, Joncryl 817, Joncryl 819, Joncryl 820, Joncryl 821, Joncryl 901, Joncryl 903, Joncryl 843, Joncryl 848, Joncryl 67, Joncryl 690, Joncryl HPD manufactured by BASF. 671 and Joncryl HPD 696.

[0025] Thermosetting CNT ink: Thermosetting CNT ink formulation consists of V2V diluent, carbon nanotubes, a thermosetting resin binder, and a crosslinker or crosslinkers.

[0026] In some embodiments, the CNT concentration and CNT / binder ratio are as described above.

[0027] In some embodiments, the crosslinkable resinous binder includes, but is not limited to, the following: 1. Neocryl 818, Neocryl 819, Neocryl 890 manufactured by DSM, Joncryl 817, Joncryl 819, Joncryl 820, Joncryl 821, Joncryl 901, Joncryl 903, Joncryl 857, Joncryl 586, Joncryl 611, Joncryl 678, Joncryl 680, Joncryl 682 manufactured by BASF, Joncryl 683, Joncryl 693, Joncryl ECO 675, Joncryl ECO684, Joncryl 843, Joncryl 848, Joncryl 67, Joncryl 690, Joncryl HPD 671, Joncryl HPD manufactured by BASF Acrylic copolymers with carboxyl functionality, including but not limited to 696. 2. Crosslinkers include, but are not limited to, (A) polycarbodiimide crosslinkers, including but not limited to, Crosslinker CX-300 and Crosslinker XL-1 from DSM; Picassian® XL-702, XL-712, XL-752, XL-762 from STAHL, ZOLDINE® XL-29SE from ANGUS; (B) Crosslinker CX-100 and NeoAdd™ PAX-521 from DSM, Picassian® XL-048 and Picassian® XL-706 from STAHL, PZ-28 and PZ-33 from PolyAziridine LLC. 3. The curing process depends on temperature and time.

[0028] UV and thermal (dual cure) CNT inks: The UV and thermal dual-cure CNT ink formulation consists of a "V2V" diluent, a CNT dispersion in alcohol and / or amine, a binder resin mixture of radiation curable acrylic copolymer and acrylic copolymer with carboxy functional groups, a photoinitiator, and a crosslinker, where the UV curable acrylic copolymer, the heat curable acrylic copolymer with carboxy functional groups, the photoinitiator, and the thermal crosslinker are defined above. The CNT concentration and CNT / binder ratio are as above.

[0029] Printing process: CNT ink printing process: 355 polyester mesh screen is placed with a snap-off distance of 3mm. The AgNW-coated PET or polycarbonate substrate is fixed with tape onto a smooth surface. Apply approximately 5 ml of the curable CNT ink on top of the pattern. The screen is infused with CNT ink by drawing the liquid over the pattern with a squeegee. With a squeegee angle of approximately 75 degrees and uniform (even) pressure and velocity, the ink is sheared through the screen and onto the substrate. The coated sample is dried in a convection oven set at 105° C. with blowing air for 10 minutes.

[0030] Curing process: For radiation curing systems, the coated sample (coating facing the radiation source) is placed under the radiation source, e.g., UV lamp, for a certain period of time to achieve the required radiation dose. The radiation curing device may be a stationary system or a conveyor system, e.g., a conveyor UV system with mercury lamps, LED lamps, xenon lamps, and the conveyor belt speed is set to achieve a UV curing dose of 1400mJ / cm^2, and the UV CNT coated film may be placed on the feed end of the UV conveyor system, and the UV curing process is completed after the coated film passes through the UV irradiation zone and exits the conveyor system. The UV curing process can also be done without a conveyor system, as long as the dose is in the range of about 400 to about 1800mJ / cm^2.

[0031] For the thermal curing process, in some embodiments, the samples are cured at 110° C. for 60 seconds (with 60-600 seconds being the preferred range).

[0032] After initial sample drying in the printing process, in a combined UV and thermal curing process, curing can be achieved with a first UV cure / second thermal cure, or a first thermal cure / second UV cure.

[0033] Pattern Etching Process: The radiation-cured samples were then sprayed with a 1-20% aqueous solution of ferric nitrate (Fe(NO3)3) for 5-200 seconds. Afterwards, using another wash bottle, the samples were sprayed with deionized water on both sides of the film for 30 seconds. The films were then tapped with a lint-free cloth to remove large water droplets and baked in a convection oven at 105°C for 1 minute. Alternatively, etching can be performed by an automated system consisting of etching, washing, and drying, with a motor-driven film transport section.

[0034] measurement: The electrical properties of the CNT ink printed film sheet were measured using an R-check 4-point sheet resistance meter (manufactured by EDTM). ) is used to measure the

[0035] The optical properties of total transmission and transmitted haze are measured with BYK Haze-Guard.

[0036] The ASTM D3359 tape adhesion test, which measures the adhesion of ink to a plastic film substrate, is failed by any peeling of the printing ink (less than 5B as defined by ASTM D3359).

[0037] An abrasion test is conducted by rubbing the surface of the printed ink with a cloth, and any product that has the printed ink peeled off is deemed to have failed.

[0038] The ethanol resistance rubbing test is performed by wiping the printed ink surface with a cloth saturated with ethanol, followed by a 30-second drying time at ambient temperature and measuring the sheet resistance. If the sheet resistance changes less than 10% of its original value after five wipe cycles, the sample is considered to have passed the test.

[0039] The CNT-based hybrid TCF 10 (Figure 1) includes a MM layer 13 containing metal traces 14-16 and an overlying CNT ink layer 18 that adheres to the top surface of the substrate 12 and encapsulates the MM layer 13 with a conductive medium. After the exposed MM (i.e., areas where the CNT ink is not printed) is removed by chemical etching, the circuit pattern results. Note that the circuit pattern could alternatively or additionally be created from a metal nanowire layer rather than a metal mesh layer.

[0040] 2A-2D show the results of a process for making a TCF of the present disclosure. It should be noted that the dimensions and other aspects of FIGS. 2A-2D are not to scale, are for illustration only, and may be exaggerated. An actual example is described below. Assembly 20, FIG. 2A, includes a substrate 22 carrying a MM including traces 24-27. The MM can be fabricated on the substrate by various means as described herein. The MM can also include various conductive materials (e.g., metals), as further described herein. The MM includes a series of thin traces (lines) that are electrically connected. The traces are typically, but not necessarily, laid out in a regular pattern.

[0041] 2B shows a further assembly 30 in which the MM is overplated with a second metal (in this non-limiting example, the second metal is copper). Thus, traces 24-27 are covered by a generally thick layer of the second metal, including portions 34-37, forming thick, non-porous MM traces 40-43, respectively.

[0042] Figure 2C shows a further assembly 50 in which CNT ink 48 is printed or otherwise disposed over some or all of the MM layer depicted in Figure 2B. In this figure, ink 48 is printed over traces 41 and 42, but not over traces 40 and 43. Thus, traces 40 and 43 are exposed, and traces 41 and 42 are covered by a conductive medium forming conductive lines or regions 49.

[0043] 2D shows the final TCF 60, in which the exposed traces 40 and 43 have been etched away, as described in more detail elsewhere herein, leaving conductors 49 on the substrate 22.

[0044] One exemplary method 70 for manufacturing TCF is shown in FIG. 3. In step 72, a suitable substrate is provided. In step 74, a metal mesh is printed on the surface of the substrate. In step 76, a second metal (e.g., copper) is plated onto the metal mesh. Step 76 is optional, and if the MM itself has an acceptable Rs, it may not be necessary to increase the thickness (i.e., height) of the MM traces. Adding additional plating metal increases the volume of the MM traces and reduces their resistance. It may also help make the thin MM more robust and bond better with the conductive ink. In step 78, a curable conductive medium (referred to as "ink") is printed onto selected areas of the MM to form part of the circuit. In one embodiment, the curable ink includes carbon nanotubes as the conductive medium and also contains binders and other ingredients as described herein. CNT inks are further described elsewhere herein. In step 80, the ink is cured in a manner appropriate for the particular ink, as further described elsewhere herein. The final step 82 contemplates etching the exposed MM / copper to leave only the circuit on the substrate.

[0045] FIG. 4 is a graph showing the ink viscosity for different levels of CNT. As is evident from the curves in FIG. 4, the CNT concentration directly affects the viscosity of the ink. In general, the inks herein should have a viscosity in the range of about 1,000 cp to about 50,000 cp for screen printing using conventional printing techniques and be useful without the need for surfactants as discussed above. In the present ink, 1 gram / liter of CNT corresponds to about 0.1%, which corresponds to a viscosity of about 50,000 cp. It is evident from the viscosity graph in FIG. 4 that with 3 grams / liter of CNT, the ink will likely be in the region where it cannot be used for printing, several million cp. Even with 0.2% CNT, it is expected to be about 700,000 cp.

[0046] Results of the preferred embodiment: Performance: The UV and / or thermally curable CNT inks yield advantages of better adhesion to substrates with a layer of metal nanowire coating or a metal mesh layer, better abrasion resistance and chemical resistance during etching processes than the same TCF design but using a non-cured resin binder, while maintaining comparable electrical and optical properties in terms of VLT and haze number.

[0047] Example 1: UV-curable CNT ink with a CNT concentration of 0.1 g / l and a CNT / binder ratio of 1:120. The binder resin contains 60 wt% UV-curable polymer Lumicryl 245 from Enstron and 40 wt% non-UV-curable polymer Neocryl B-890 from DSM. Photoinitiator Esacure KIP 100F is used with a photoinitiator to binder ratio of 1:50. A non-UV-cured CNT ink (identified as VC200) was tested for comparison (as a control). VC200 has the same CNT, polymer binder and diluent concentration as the UV CNT ink, but the resin binder is a non-curable thermoplastic polymer, e.g., 100% NeoCryl® B-890.

[0048] UV CNT ink and VC200 were screen printed onto C3 Nano AgNW coated PET film (125μm thick) with a sheet resistance of 30+ / -2Ω / cm. The screen mesh size was 305 and drying conditions were as previously described. The UV CNT ink printed samples were then UV cured with a UV dose of 1400mj / cm^2. The UV cured samples and the coated VC200 samples were subsequently etched with a 10% aqueous solution of ferric nitrate (Fe(NO3)3) for 12 seconds, followed by rinsing with deionized water and oven drying as described above. Performance tests were performed on the dry etched samples and the test results are shown in Table 1. The tests were repeated with C3 Nano AgNW PET films with sheet resistances of 10Ω / cm and 75Ω / cm.

[0049] The test data shown in Table 1A, Table 1B and Table 1C clearly show that the UV-cured CNT ink exhibits superior adhesion to the AgNW film substrate, superior abrasion resistance and solvent resistance compared to the VC200 control with the non-curable CNT ink.

[0050] [Table 1A]

[0051] [Table 1B]

[0052] [Table 1C]

[0053] Example 2: A thermosetting CNT ink with a CNT concentration of 0.1 g / l and a CNT / binder ratio of 1:120. The binder resin consists of a carboxylic acid functional acrylic resin Joncryl HPD 671 from BASF and a hardener CX-100 from DSM, with a crosslinker to polymer ratio of 1:12. For comparison, a non-curable CNT ink VC200 was tested, which has a CNT concentration of 0.1 g / l and a CNT / polymer binder ratio of 1:120, the same as the thermosetting CNT ink.

[0054] The thermosetting CNT ink and VC200 were screen printed (screen size 305) onto C3 Nano AgNW coated PET film (thickness 125um) with a sheet resistance of 75+ / -2Ω / cm2. The printed film samples are dried in a belt conveyor oven set at 110°C with a drying time of 180 seconds. The thermosetting samples can be cured at ambient temperature for 120 hours or accelerated cured at 110°C for 600 seconds. The VC200 printed and thermosetting samples were subsequently etched with a 10% aqueous solution of ferric nitrate (Fe(NO3)3) for 12 seconds, washed with deionized water, and then dried in an oven at 110°C for 60 seconds. Performance testing was performed and the test results are shown in Table 2. The curable ink shows excellent performance in abrasion resistance, solvent wipe resistance, and etching resistance.

[0055] [Table 2]

[0056] Example 3: Dual-cured CNT ink with a CNT concentration of 0.1 g / l and a CNT / binder ratio of 1:120. The binder resin consists of 30 wt% UV-curable polymer Lumicryl 245 from Enstron, 70 wt% carboxylic acid functional acrylic resin Joncryl HPD 671 from BASF, type II photoinitiator Omnirad 4PBZ and co-initiator Esacure A198 from IGM, and thermal curing agent CX-100 from DSM. For comparison, a non-curable CNT ink VC200 was tested, which has the same CNT concentration of 0.1 g / l and CNT to polymer binder ratio of 1:120 as the dual-cured CNT ink.

[0057] The dual curable CNT ink and VC200 were screen printed (screen size 305) onto C3 Nano AgNW coated PET film (thickness 125um) with a sheet resistance of 75+ / -2Ω / cm. The printed film sample was dried in a conveyor belt oven set at 110°C with a drying time of 180 seconds. The sample was then UV cured with a UV dose of 1400mj / cm^2 and then thermally cured at 110°C for 600 seconds. The cured sample was then etched with a 10% aqueous solution of ferric nitrate (Fe(NO3)3) for 12 seconds. Performance testing was then performed and the test results are shown in Table 3. The dual cured ink shows superior performance in etch resistance compared to only UV cured and only thermal cured CNT inks.

[0058] [Table 3]

[0059] Although several aspects of at least one embodiment have been described above, it will be understood that various changes, modifications, and improvements will readily occur to those skilled in the art. Such changes, modifications, and improvements are intended to be part of this disclosure and within the scope of the present invention. Accordingly, the foregoing description and drawings are illustrative, and the scope of the present invention should be determined from a proper interpretation of the appended claims and their equivalents.

Claims

1. A curable resin binder; a catalyst configured to be activated to cure the resin binder; a viscous-evaporating diluent; and a carbon nanotube (CNT) comprising: A curable carbon nanotube ink, characterized in that the CNT concentration in the ink ranges from about 0.001% to about 0.2% by weight.

2. 10. The curable carbon nanotube ink of claim 1, wherein the resin binder concentration in the ink ranges from about 0.1% to about 5% by weight.

3. 10. The curable carbon nanotube ink of claim 1, wherein the catalyst concentration in the ink ranges from about 0.001% to about 1.0% by weight.

4. 10. The curable carbon nanotube ink of claim 1, wherein the diluent concentration in the ink ranges from about 90% to about 99% by weight.

5. 10. The curable carbon nanotube ink of claim 1, further comprising a filler resin having a concentration in the ink ranging from about 0.1% to about 5% by weight.

6. The curable carbon nanotube ink of claim 1 , wherein the resin binder is radiation curable.

7. The curable carbon nanotube ink of claim 6 , wherein the resin binder comprises one or more of a UV curable multifunctional acrylic copolymer, a UV curable urethane polymer, or a UV curable polyester.

8. The curable carbon nanotube ink of claim 7, further comprising one or more of a non-UV curable resin, a multifunctional oligomer, or a monomer.

9. 7. The curable carbon nanotube ink of claim 6, wherein the catalyst comprises a Type I or Type II free radical photoinitiator.

10. The curable carbon nanotube ink of claim 1 , wherein the resin binder is thermosetting.

11. The curable carbon nanotube ink of claim 10 , wherein the resin binder comprises one or more of an acrylic copolymer, a urethane polymer, or a polyester having acidic functional groups.

12. The curable carbon nanotube ink of claim 10, wherein the catalyst comprises at least one of a polyaziridine crosslinker, a polycarbodiimide crosslinker, or a peroxide type catalyst.

13. The curable carbon nanotube ink of claim 1 , wherein the resin binder comprises a mixture of a UV curable resin and a thermosetting resin.

14. 10. The curable carbon nanotube ink of claim 1, having a viscosity of about 1,000 cP to about 50,000 cP.

15. The curable carbon nanotube ink of claim 1 , wherein the CNTs comprise single-walled CNTs.

16. A transparent conductive film (TCF), A polymer film substrate; a metal nanowire layer or a metal mesh layer on the film surface; and a cured carbon nanotube (CNT) ink covering at least a portion of the metal nanowire layer or metal mesh layer, the CNT ink comprising a curable resin binder, a catalyst configured to be activated to cure the resin binder, a viscous-evaporating diluent, and CNTs, the CNT concentration range in the ink being about 0.001% to about 0.2% by weight.

17. 17. The transparent conductive film of claim 16, exhibiting excellent electrical conductivity, high visible light transmittance, and excellent adhesion of the metal nanowire layer or metal mesh layer and the cured CNT ink to the substrate.

18. 17. The transparent conductive film of claim 16, exhibiting better adhesion to the metal nanowire layer or metal mesh layer, improved abrasion resistance, and better solvent and chemical resistance during etching processes compared to TCFs made with non-curable CNT inks.

19. 20. The transparent conductive film of claim 18, which maintains excellent electrical conductivity, high visible light transmittance, and low haze.

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