Manufacturing method of laminate

Abstract

The present invention addresses the problem of providing a method for producing a laminate that exhibits a low resistance value and excellent light transmissivity. The method for producing a laminate according to the present invention has a first step that rotates a base material and spin coats a composition containing metal nanowires and a solvent on the surface of the base material and a second step that rotates the base material obtained in the first step and spin coats a composition containing metal nanowires and a solvent on the surface of the base material that was spin coated with the above composition in the first step. The position of the center of rotation of the base material in the first step differs from the position of the center of rotation of the base material in the second step. Furthermore, the laminate obtained includes the base material and a metal nanowire layer.

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a laminate. [Background technology]

[0002] Patent Document 1 discloses a transparent conductive film containing metal nanowires, and discloses that a metal nanowire-containing coating liquid is applied to a substrate to form a transparent conductive film containing metal nanowires. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-216535 Summary of the Invention

[0004] The present disclosure relates to a method for producing a laminate including a substrate and a metal nanowire layer, the method comprising: a first step of rotating a substrate and spin-coating a composition containing metal nanowires and a solvent onto the surface of the substrate; and a second step of rotating the substrate obtained in the first step and spin-coating a composition containing metal nanowires and a solvent onto the surface of the substrate spin-coated with the composition in the first step, wherein the position of the center of rotation of the substrate in the first step is different from the position of the center of rotation of the substrate in the second step. [Brief explanation of the drawings]

[0005] [Figure 1] 1A to 1C are diagrams for explaining an example of an embodiment of a method for producing a laminate. [Figure 2] FIG. 2 is a diagram illustrating the substrate after the first step has been performed. [Figure 3] FIG. 10 is a diagram illustrating the substrate after the second step has been performed. [Figure 4] FIG. 2 is a diagram illustrating a method for measuring the resistance values ​​of the laminates of the examples and comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0006] The method for producing the laminate of this embodiment will be described in detail below. A laminate including a substrate and a metal nanowire layer is desired to exhibit low resistance and excellent light transmittance. According to the laminate manufacturing method of the present embodiment, a laminate having the above properties can be manufactured. In this specification, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0007] The method for producing the laminate of this embodiment includes the following first and second steps. First step: A step of spin-coating a composition containing metal nanowires and a solvent (hereinafter simply referred to as "composition") onto the surface of the substrate by rotating the substrate. Step 2: rotating the substrate obtained in Step 1, and spin-coating a composition containing metal nanowires and a solvent onto the surface of the substrate that has been spin-coated with the composition in Step 1. The procedure of each step will be explained below with reference to the drawings.

[0008] <1st process> The first step is to rotate the substrate and spin-coat the composition onto the surface of the substrate. Figure 1 is a plan view of the substrate 10 used in the first step. As shown in Figure 1, the substrate 10 is perfectly circular, with the center of gravity 12 of the substrate 10 located at its center. In the first step, the composition is supplied to the surface of the substrate 10, and then the substrate 10 is rotated around the first rotation center 14 (the rotation center of the substrate in the first step). By performing such a process, the metal nanowires tend to be distributed radially around the position of the first rotation center 14, as shown by the dashed line in FIG. The parts and materials used in this process, as well as the procedure, will be described in detail below.

[0009] (base material) The substrate is a member used when performing the spin coating, and serves as a member for supporting the metal nanowire layer when a laminate described below is formed. The substrate is preferably a spectacle lens substrate. The type of spectacle lens substrate is not particularly limited, and examples thereof include ordinary spectacle lens substrates made of plastic, inorganic glass, etc., with plastic spectacle lens substrates being preferred in terms of ease of handling. The type of plastic eyeglass lens substrate is not particularly limited, but examples include finished lenses in which both the convex and concave surfaces are optically finished and molded to match the desired power, semi-finished lenses in which only the convex surface is finished as an optical surface (spherical, rotationally symmetric aspherical, progressive surface, etc.), and semi-finished lenses in which the concave surface is processed and polished to match the wearer's prescription. The type of plastic (so-called resin) that constitutes the plastic eyeglass lens substrate is not particularly limited, but examples include (meth)acrylic resins, thiourethane resins, allyl resins, episulfide resins, polycarbonate resins, polyurethane resins, polyester resins, polystyrene resins, polyethersulfone resins, poly-4-methylpentene-1 resins, and diethylene glycol bisallyl carbonate resins (CR-39).

[0010] There are no particular restrictions on the thickness of the plastic eyeglass lens substrate, but from the standpoint of ease of handling, it is often about 1 to 30 mm. The refractive index of the plastic eyeglass lens substrate is not particularly limited. Furthermore, the plastic eyeglass lens substrate does not have to be transparent as long as it has light-transmitting properties, and may contain an ultraviolet absorber or a dye that absorbs light in a specific wavelength range from the ultraviolet to the infrared region.

[0011] The planar shape of the substrate (the shape of the substrate when observed from the normal direction of the surface of the substrate) is not particularly limited, and may be a perfect circle as shown in FIG. 1 above, or may have any other shape.

[0012] (composition) The composition includes metal nanowires and a solvent.

[0013] The metal contained in the metal nanowires contained in the composition is preferably at least one selected from the group consisting of silver, gold, copper, nickel, and platinum, in that it results in a lower resistance value of the laminate (in other words, a lower resistance value of the metal nanowire layer) (hereinafter also simply referred to as "a lower resistance value"). Silver or gold is more preferred, and silver is even more preferred. Metal nanowires are conductive materials made of metal, shaped like needles or threads, and having a diameter on the order of nanometers. Metal nanowires may be linear or curved.

[0014] The diameter of the metal nanowires is not particularly limited, but is preferably 500 nm or less, more preferably 200 nm or less, even more preferably 100 nm or less, and particularly preferably 40 nm or less, in order to improve the light transmittance of the metal nanowire layer. The lower limit is often 10 nm or more. The diameter of the metal nanowires is an average value, and is determined by observing the cross section of the metal nanowires using a scanning electron microscope or a transmission electron microscope, measuring the diameter of the metal nanowires at 20 points, and calculating the arithmetic mean of the measured diameters. Note that if the cross section is not perfectly circular, the major axis is used as the diameter.

[0015] The length of the metal nanowires is not particularly limited, but is preferably 5 to 1000 μm, more preferably 10 to 500 μm, and even more preferably 20 to 300 μm, in order to lower the resistance value. The length of the metal nanowires is an average value, which is obtained by measuring the lengths of 20 metal nanowires using a scanning electron microscope or a transmission electron microscope and calculating the arithmetic average.

[0016] The ratio of the diameter d to the length L of the metal nanowires (aspect ratio: L / d) is not particularly limited, but is preferably 10 to 100,000, and more preferably 50 to 100,000. The method for measuring the diameter and length of the metal nanowires is as described above.

[0017] The solvent contained in the composition may be water or an organic solvent. The type of organic solvent is not particularly limited, and examples thereof include alcohol-based solvents, ketone-based solvents, ether-based solvents, ester-based solvents, hydrocarbon-based solvents, halogenated hydrocarbon-based solvents, amide-based solvents, sulfone-based solvents, and sulfoxide-based solvents. Among these, alcohol solvents are preferred, and isopropyl alcohol (IPA) is more preferred.

[0018] The content of the metal nanowires in the composition is not particularly limited, but is preferably 98% by mass or more, and more preferably 99% by mass or more, based on the total solid content in the composition. The above-mentioned solid content refers to the components in the composition excluding the solvent, and is considered to be solid content even if the composition is in a liquid state.

[0019] The content of the metal nanowires in the composition is preferably 0.1 to 10.0 g / L, more preferably 0.3 to 6.0 g / L, relative to the total volume of the composition.

[0020] (Procedure for the first step) The procedure for the first step is not particularly limited as long as it allows the composition to be spin-coated onto the surface of the substrate. For example, a method may be used in which a known spin coater is used to supply the composition onto the surface of the substrate and then rotate the substrate.

[0021] The method for supplying the composition onto the surface of the substrate is not particularly limited, and known methods can be used. For example, a method in which the composition is discharged onto a predetermined position on the substrate using a discharge nozzle can be used. The position at which the composition is discharged is preferably the position of the rotation center of the substrate in the first step. The composition may be supplied in one batch or in multiple batches. When the composition is supplied in multiple batches, the substrate may be rotated each time the composition is supplied, or the substrate may be rotated after the composition is supplied multiple times. The amount of the composition to be supplied can be appropriately changed depending on the size and type of the substrate to be used and the composition, and is preferably 0.1 to 10 mL, more preferably 0.5 to 5 mL.

[0022] The method for rotating the substrate is not particularly limited, and examples thereof include a method using a known spin coater. In one example of a method using a spin coater, the substrate can be rotated by holding the substrate on a rotating table in the spin coater and rotating the rotating table. The mechanism for holding the substrate on the rotary table includes a vacuum suction mechanism that reduces the pressure with a vacuum pump to fix the substrate to the rotary table, and a mechanical mechanism that mechanically fixes the substrate to the rotary table.

[0023] The rotation speed of the substrate during spin coating is not particularly limited, and may be, for example, 300 to 3000 rpm (Rotation per minute), preferably 500 to 2000 rpm.

[0024] After the composition is spin-coated, a drying treatment may be carried out to remove the solvent contained in the composition. A method for carrying out the drying treatment includes a heat treatment. The heating temperature during the heat treatment is not particularly limited, but is preferably 70 to 150°C, and more preferably 90 to 130°C. The heating time is preferably 0.5 to 90 minutes, and more preferably 1 to 60 minutes.

[0025] <Second process> The second step is a step of rotating the substrate obtained in the first step and spin-coating a composition containing metal nanowires and a solvent onto the surface of the substrate that has been spin-coated with the composition in the first step. By carrying out this step, a metal nanowire layer is formed on the substrate. In the second step, the composition obtained in the first step is supplied onto the surface of the substrate that has been spin-coated with the composition, and then the substrate 10 is rotated around the second rotation center 16 (the rotation center of the substrate in the second step). Note that the first rotation center 14 and the second rotation center 16 are at different positions. By carrying out such a process, the metal nanowires tend to be distributed radially around the position of the second center of rotation 16, as shown by the dashed line in Fig. 3. As a result, as shown in Fig. 3, between the first center of rotation 14 and the second center of rotation 16, there are many points at which the metal nanowires arranged radially around the first center of rotation 14 intersect with the metal nanowires arranged radially around the second center of rotation 16. As the number of points at which the metal nanowires intersect increases, the resistance in the in-plane direction can be reduced without reducing the light transmittance. The materials and procedures used in this step are described in detail below.

[0026] The definition and preferred embodiments of the composition used in the second step are the same as those of the composition used in the first step. The composition used in the first step and the composition used in the second step may be the same type of composition or different types of compositions as long as they contain metal nanowires and a solvent. Different types of compositions refer to, for example, compositions with different concentrations of metal nanowires or compositions using different types of metal nanowires.

[0027] (Procedure for the second step) The procedure for the second step is not particularly limited as long as it allows the composition to be spin-coated onto the surface of the substrate, and examples thereof include a method in which the composition is supplied onto the surface of the substrate and the substrate is rotated. The procedure for the second step may be the same as that described for the first step.

[0028] As long as the position of the rotation center of the substrate in the first step and the position of the rotation center of the substrate in the second step are different, there are no particular limitations on the positional relationship between them. More specifically, as shown in Fig. 1, the distance d between the first rotation center 14 and the second rotation center 16 may be greater than 0 mm. The distance d is preferably 3 mm or greater, and more preferably 5 mm or greater, in order to reduce the resistance. Furthermore, the distance d is not particularly limited, but is preferably 30 mm or less, and more preferably 20 mm or less.

[0029] In the embodiment shown in FIG. 1, the first rotation center 14 and the second rotation center 16 are arranged to be substantially point-symmetric with respect to the center of gravity 12 of the substrate, but the method for manufacturing the laminate of this embodiment is not limited to this embodiment. For example, the position of the first rotation center 14 may coincide with the position of the center of gravity 12 of the substrate, and the position of the second rotation center 16 may coincide with the position of the center of gravity 12 of the substrate. Furthermore, the center of gravity 12 of the substrate does not have to be located on the line segment connecting the first rotation center 14 and the second rotation center 16.

[0030] <Other processes> The method for producing a laminate of this embodiment may include steps (other steps) other than the above-mentioned steps 1 and 2. The other steps will be described below.

[0031] (Substrate cleaning process) The method for producing a laminate of this embodiment may include a substrate washing step of washing the surface of the substrate before the first step. The substrate cleaning step is not particularly limited as long as it can clean the surface of the substrate. Specific methods for the substrate cleaning step include a method of supplying gas to the surface of the substrate, a method of supplying a cleaning liquid to the surface of the substrate, and a method of contacting the surface of the substrate with a cleaning brush or the like (including cloth, porous material, paper, etc.) containing a cleaning liquid. The substrate cleaning step may be carried out by combining two or more of the above methods.

[0032] (Moisture supply process) Furthermore, since the resistance value becomes lower after the composition is spin-coated in the above steps 1 and 2, the method for producing a laminate of this embodiment may include a moisture supplying step of supplying moisture to the substrate on which the composition has been spin-coated and drying it. By performing this step, the metal nanowires are more strongly bonded to each other by capillary forces. A specific example of the moisture supplying step is a method in which water vapor is supplied to the metal nanowire layer until minute droplets (cloudiness) are generated, and then the metal nanowire layer is dried until the minute droplets disappear. The water supplying step may be repeated, preferably 2 to 20 times, more preferably 3 to 10 times. The moisture supplying step is preferably carried out after each of the first step and the second step. The moisture supplying process can also be referred to Y. Liu et al., Nano Lett. 2017, 17, 2, 1090-1096.

[0033] (3rd step) The method for producing a laminate of this embodiment may further include, after the second step, a third step of rotating the substrate obtained in the second step and spin-coating a composition containing metal nanowires and a solvent onto the surface of the substrate that has been spin-coated with the composition in the second step. That is, the method for producing a laminate of this embodiment may include a step of spin-coating the composition onto a substrate in addition to the above-mentioned steps 1 and 2. The position of the rotation center of the substrate in the third step may coincide with or be different from the position of the rotation center of the substrate in the first step. Furthermore, the position of the rotation center of the substrate in the third step may coincide with or be different from the position of the rotation center of the substrate in the second step. In particular, it is preferable that the position of the rotation center of the substrate in the third step is different from both the position of the rotation center of the substrate in the first step and the position of the rotation center of the substrate in the second step. Furthermore, the third step may be performed only once or may be performed multiple times. When the third step is performed multiple times, the positions of the rotation centers of the substrate in the third step performed multiple times may be the same or different from each other.

[0034] <Laminate> The laminate that can be produced by the above-described method for producing a laminate is a laminate that includes a substrate and a metal nanowire layer. The structure of the laminate to be manufactured will be described in detail below. The substrate of the laminate is the same as the substrate described above, and therefore a description thereof will be omitted.

[0035] (metal nanowire layer) The metal nanowire layer is a layer formed by carrying out steps 1 and 2. The metal nanowire layer has electrical conductivity and can impart antistatic properties to the substrate. The metal nanowire layer is a layer composed of metal nanowires. In other words, the metal nanowire layer is an aggregate of metal nanowires (a layered aggregate of metal nanowires) in which a plurality of metal nanowires are aggregated to form a layer.

[0036] The metal nanowire layer may be disposed so as to cover the entire surface of one of the main surfaces of the substrate, or may be disposed so as to cover a portion of one of the main surfaces of the substrate. In other words, the metal nanowire layer may be disposed so as to cover at least a portion of the surface of the substrate (particularly, one of the two main surfaces of the substrate). The coverage of the metal nanowire layer on the substrate surface is not particularly limited, but is often 5.0% or more. In order to achieve a desired effect, it is preferably 20.0% or more, more preferably 25.0% or more, and even more preferably 40.0% or more. The upper limit is not particularly limited, and can be 100%, but in order to achieve better transparency of the laminate, it is preferably 85.0% or less, more preferably 75.0% or less, and even more preferably 65.0% or less. The coverage of the metal nanowire layer is determined by the following method. First, the laminate is observed at a magnification of 500x using an optical microscope, and three randomly selected locations are determined. The percentage of the area where the metal nanowires are present in the total area at each location (length: 500 μm, width: 660 μm) is calculated, and the arithmetic average of these values ​​is calculated.

[0037] The average thickness of the metal nanowire layer is not particularly limited, but is preferably 1 to 300 nm, more preferably 10 to 100 nm, in terms of achieving a better desired effect. The average thickness of the metal nanowire layer is determined by the following method. First, the spectral reflectance characteristics of the laminate are measured using an optical measuring device (Olympus Corporation, reflectance measuring device USPM-RUIII), and the thickness is determined by a curve fitting method.

[0038] The laminate may include other members in addition to the substrate and the metal nanowire layer. The laminate may include a hard coat layer on the metal nanowires. The hard coat layer is a layer that imparts scratch resistance to the substrate, and is disposed so as to cover the metal nanowire layer, thereby protecting the metal nanowire layer from the outside. The hard coat layer preferably has a pencil hardness of "H" or higher according to the test method specified in JIS K5600.

[0039] As the hard coat layer, a known hard coat layer can be used, for example, an organic hard coat layer, an inorganic hard coat layer, and an organic-inorganic hybrid hard coat layer. For example, in the field of eyeglass lenses, an organic-inorganic hybrid hard coat layer is generally used.

[0040] The method for forming the hard coat layer is not particularly limited, and examples thereof include a method in which a composition for forming a hard coat layer is applied onto the metal nanowire layer to form a coating film, and then the coating film is subjected to a curing treatment such as light irradiation treatment.

[0041] The laminate may further include a primer layer between the substrate and the metal nanowire layer, which improves the adhesion of the metal nanowire layer and the hard coat layer to the substrate. The material constituting the primer layer is not particularly limited, and known materials can be used, for example, resins are mainly used. The type of resin used is not particularly limited, and examples thereof include polyurethane resins, epoxy resins, phenolic resins, polyimide resins, polyester resins, bismaleimide resins, and polyolefin resins, with polyurethane resins being preferred.

[0042] The method for forming the primer layer is not particularly limited, and any known method can be used. For example, a method can be used in which a primer layer-forming composition containing a predetermined resin is applied to a spectacle lens substrate, and a curing treatment is performed as necessary to form a primer layer.

[0043] The laminate may also include an anti-reflection film. The structure of the anti-reflection film is not particularly limited, and may be a single-layer structure or a multi-layer structure. The anti-reflection film is preferably an inorganic anti-reflection film, which is an anti-reflection film made of an inorganic compound. In the case of a multilayer structure, a structure in which low-refractive index layers and high-refractive index layers are alternately stacked is preferred. Examples of materials constituting the high-refractive index layers include oxides of titanium, zirconium, aluminum, niobium, tantalum, or lanthanum. Examples of materials constituting the low-refractive index layers include oxides of silica. The method for producing the anti-reflective coating is not particularly limited, and examples thereof include dry methods such as vacuum deposition, sputtering, ion plating, ion beam assisted deposition, and chemical vapor deposition (CVD).

[0044] <Application> The laminate can be used for various purposes. In particular, when a spectacle lens substrate is used as the substrate, the laminate can be used as a spectacle lens. [Example]

[0045] The above embodiment will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0046] <Comparative Example 1 and Examples 1 to 3> (1st step) A plano-convex lens substrate (circular, diameter 75 mm) with a refractive index of 1.60 was prepared as the substrate. Both surfaces of the plano-convex lens substrate were untreated. First, the convex surface of the plano-convex lens substrate was wiped with a nonwoven fabric impregnated with acetone to clean the surface. Next, the plano-convex lens substrate was set on a spin coater so that the flat side of the plano-convex lens substrate faced the vacuum chuck. In Comparative Example 1, the plano-convex lens substrate was set on the spin coater so that the position of the center of gravity of the plano-convex lens substrate coincided with the position of the rotation center of the spin coater. On the other hand, in Examples 1 to 3, the plano-convex lens substrate was set on the spin coater so that the distance between the position of the center of gravity of the plano-convex lens substrate and the position of the rotation center of the spin coater was half the value of the distance between the rotation centers shown in the table below. For example, in Example 1, the plano-convex lens substrate was set on the spin coater so that the distance between the position of the center of gravity of the plano-convex lens substrate and the position of the rotation center of the spin coater was 2.5 mm. The position of the rotation center of the spin coater corresponds to the position of the rotation center of the substrate in the first step (first rotation center 14 shown in FIG. 1).

[0047] A silver nanowire dispersion (EM Japan, NW-AG30-05G-IPA) was mixed with a predetermined amount of isopropyl alcohol (IPA) to adjust the silver nanowire concentration to 0.5 g / L, and 1 mL of the composition was dropped onto the convex surface of a plano-convex lens substrate set on a spin coater. After the composition was dropped, the plano-convex lens substrate was rotated at 1000 rpm for 60 seconds to spin-coat the composition (first step). The silver nanowires had a diameter of 30 nm and a length of 30 μm. After spin coating, the plano-convex lens substrate was removed from the vacuum chuck of the spin coater and subjected to the following treatment (corresponding to the moisture supplying step described above). First, breath was blown onto the convex surface of the plano-convex lens substrate for about 1 to 2 seconds, causing fogging due to the moisture contained in the breath on the convex surface. Next, the lens was dried at room temperature for about 5 to 10 seconds until the fogging disappeared. The breath blowing process and the drying process were repeated five times each.

[0048] (2nd process) Next, the plano-convex lens substrate obtained above was set on a spin coater so that the flat side of the plano-convex lens substrate faced the vacuum chuck. In Comparative Example 1, the plano-convex lens substrate was set on the spin coater so that the position of the center of gravity of the plano-convex lens substrate coincided with the position of the center of rotation of the spin coater. Meanwhile, in Examples 1 to 3, the plano-convex lens substrate was set on the spin coater so that the positions of the center of rotation of the spin coater and the center of rotation of the substrate in the first step were the values ​​of the distance between the rotation centers shown in the table below. However, when viewed from the top of the plano-convex lens substrate, the positions of the center of rotation of the substrate in the second step and the center of rotation of the substrate in the first step were located on either side of the center of gravity of the plano-convex lens substrate (see FIG. 1 ). More specifically, in Example 1, the center of gravity of the plano-convex lens substrate was located at the center of the line segment connecting the positions of the center of rotation of the substrate in the first step and the position of the center of rotation of the substrate in the second step. The rotation center of the spin coater corresponds to the position of the rotation center of the substrate in the second step (second rotation center 16 shown in FIG. 1). In the table, a distance between rotation centers of 0 mm means that the position of the rotation center of the substrate in the first step coincides with the position of the rotation center of the substrate in the second step.

[0049] 1 mL of the composition used in the first step was dropped onto the convex surface (the surface on which the metal nanowire layer was formed) of the plano-convex lens substrate set on a spin coater. After the composition was dropped, the plano-convex lens substrate was rotated at 1000 rpm for 60 seconds to spin-coat the composition, thereby forming a metal nanowire layer (silver nanowire layer) (second step). After the metal nanowire layer was formed, the plano-convex lens substrate was removed from the vacuum chuck of the spin coater, and a moisture supplying treatment was carried out in the same manner as in the first step. By the above procedure, laminates of Comparative Example 1 and Examples 1 to 3 were obtained.

[0050] <Comparative Example 2 and Examples 4 to 6> The laminates of Comparative Example 2 and Examples 4 to 6 were obtained in the same manner as in Comparative Example 1 and Examples 1 to 3, except that the silver nanowire dispersion used to prepare the above composition was replaced with a silver nanowire dispersion (AgNW-L30) manufactured by ACS Materials and the concentration of silver nanowires in the composition was set to 5.0 g / L. The silver nanowires contained in the compositions used to prepare the laminates of Comparative Example 2 and Examples 4 to 6 had a diameter of 30 nm and a length of 150 μm.

[0051] <Comparative Example 3 and Examples 7 to 9> The laminates of Comparative Example 3 and Examples 7 to 9 were obtained in the same manner as for the laminates of Comparative Example 2 and Examples 4 to 6, except that the concentration of silver nanowires in the composition was set to 0.5 g / L.

[0052] <Evaluation> The laminates obtained in the above Examples and Comparative Examples were evaluated as follows, and the results are summarized in Table 1 below.

[0053] (resistance value) The resistance value of the laminate obtained in the examples and comparative examples was determined by attaching a copper adhesive tape to the prepared laminate and measuring the resistance between the copper adhesive tapes. The method for measuring the resistance value of the laminate will be described with reference to FIG. First, copper adhesive tape 22 was cut into a piece 1 cm wide and 4 cm long, and two pieces of the cut copper adhesive tape 22 were attached to the surface side of laminate 100 on which the metal nanowire layer was disposed so that the center of the length of the cut copper adhesive tape 22 coincided with a line passing through first rotation center 14, second rotation center 16, and center of gravity 12 of the base material, and the end of the width of the cut copper adhesive tape 22 coincided with the end of laminate 100. The portion where copper adhesive tape 22 and laminate 100 were not in contact was cut with scissors to match the shape of the end of laminate 100, and used as a test specimen. Alligator clips were connected to each of the copper adhesive tapes of the test specimens, and a digital multimeter (CDM-16D, manufactured by CUSTOM) was connected to each alligator clip to measure the resistance. The measured resistance value was taken as the resistance value of the laminate. The copper adhesive tape used was a conductive copper foil adhesive tape (No. 8323, manufactured by Teraoka Seisakusho).

[0054] (transmittance) The transmittance of the laminate at a wavelength of 550 nm was measured using a Hitachi U-4100 spectrophotometer at the center of the laminate.

[0055] In Table 1, the "AgNW type" column indicates the type of silver nanowire contained in the composition, with "1" indicating a silver nanowire with a diameter of 30 nm and a length of 30 μm, and "2" indicating a silver nanowire with a diameter of 30 nm and a length of 150 μm. In Table 1, the column "distance between rotation centers" indicates the distance between the position of the rotation center of the substrate in the first step (first rotation center) and the position of the rotation center of the substrate in the second step (second rotation center).

[0056] [Table 1]

[0057] As shown in Table 1, it was confirmed that the manufacturing method of this embodiment provided a laminate exhibiting low resistance and excellent light transmittance. [Explanation of symbols]

[0058] 10 Base material 12 Center of gravity 14 First rotation center 16 Second rotation center 100 laminate 22 Copper adhesive tape

Claims

1. A first step of spin-coating a composition containing metal nanowires and a solvent onto a surface of the substrate by rotating the substrate; a second step of spin-coating the substrate obtained in the first step with a composition containing metal nanowires and a solvent on the surface of the substrate on which the composition has been spin-coated in the first step; A method for manufacturing a laminate including the substrate and a metal nanowire layer, wherein the position of the rotation center of the substrate in the first step is different from the position of the rotation center of the substrate in the second step.

2. The method for producing a laminate according to claim 1 , wherein the distance between the position of the rotation center of the base material in the first step and the position of the rotation center of the base material in the second step is 3 mm or more.

3. 3. The method for producing a laminate according to claim 1, wherein a distance between a position of a rotation center of the substrate in the first step and a position of a rotation center of the substrate in the second step is 20 mm or less.

4. 3. The method for producing a laminate according to claim 1, wherein the metal nanowires have a length of 20 to 300 μm.

5. 3. The method for producing a laminate according to claim 1, wherein the content of the metal nanowires in the composition is 0.3 to 6.0 g / L with respect to the total volume of the composition.

6. A method for manufacturing a laminate described in claim 3, wherein the length of the metal nanowires is 20 to 300 μm.

7. A method for producing a laminate described in claim 3, wherein the content of the metal nanowires in the composition is 0.3 to 6.0 g / L relative to the total volume of the composition.

8. A method for producing a laminate described in claim 4, wherein the content of the metal nanowires in the composition is 0.3 to 6.0 g / L relative to the total volume of the composition.

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