Conductive substrate and method for manufacturing conductive substrate

Abstract

The invention relates to a conductive substrate and a method for manufacturing the conductive substrate. The technical problem to be solved is to provide a conductive substrate having excellent conductivity and excellent migration suppression performance and a method for manufacturing the conductive substrate. This conductive substrate is provided with a substrate and a conductive thin wire that is disposed on the substrate and contains silver, wherein the ratio of the amount of iodine atoms to the amount of silver atoms detected when the surface of the conductive thin wire is measured by fluorescence X-ray analysis is 0.035-0.100.

Description

Technical Field

[0001] The present invention relates to a conductive substrate having conductive fine wires and a method for manufacturing the conductive substrate. Background Art

[0002] Conductive substrates having conductive fine wires (thin line-shaped wirings showing conductivity) are widely used in various applications such as touch panels.

[0003] Regarding the conductive thin wires on the conductive substrate, for example, as disclosed in Patent Document 1, a photosensitive layer containing silver halide is sequentially subjected to an exposure process and a development process, etc., to form conductive thin wires containing metallic silver.

[0004] Patent document 1 describes a method for manufacturing a conductive substrate, which method includes: step 1, forming a thin wire containing a metal on a substrate; step 2, bringing the thin wire into contact with a solution containing an organic acid; and step 3, plating the thin wire to form a conductive thin wire.

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-161790

[0006] When a conductive substrate having conductive thin wires is used for a touch panel, for example, the conductive thin wires are required to have excellent conductivity, that is, low electrical resistance.

[0007] Furthermore, as a result of the demand for further thinning of the conductive fine wires, there is a problem that migration is more likely to occur in the metal conductive pattern formed using such conductive fine wires. If migration occurs between the conductive fine wires, conduction will occur between the conductive fine wires, and there is a possibility that the circuit function cannot be performed, so a conductive substrate with improved migration suppression performance is required.

[0008] The present inventors have studied a conductive substrate having conductive fine wires with reference to Patent Document 1, and have found that there is room for further improvement in a conductive substrate having excellent conductivity and migration suppression performance. Summary of the invention

[0009] In view of the above-mentioned actual situation, the present invention provides a conductive substrate having excellent conductivity and excellent migration inhibition performance and a method for manufacturing the conductive substrate.

[0010] [1]

[0011] A conductive substrate comprises a substrate and conductive thin wires disposed on the substrate and containing silver, wherein the ratio of the amount of iodine atoms detected when the surface of the conductive thin wires is measured by fluorescent X-ray analysis to the amount of silver atoms is 0.035 to 0.100.

[0012] [2]

[0013] The conductive substrate according to [1], wherein

[0014] The line width of the conductive thin wire is 0.1 μm or more and less than 5.0 μm.

[0015] 〔3〕

[0016] The conductive substrate according to [1] or [2], wherein

[0017] In a vertical cross section of the conductive thin wire in a direction perpendicular to the direction in which the conductive thin wire extends, a ratio of a height of the conductive thin wire to a line width of the conductive thin wire is greater than or equal to 0.6 and less than 1.5.

[0018] [4]

[0019] The conductive substrate according to any one of [1] to [3], wherein

[0020] The silver contained in the conductive thin wires is in a particle form.

[0021] 〔5〕

[0022] The conductive substrate according to any one of [1] to [4], wherein

[0023] The substrate is a flexible substrate.

[0024] [6]

[0025] The conductive substrate according to [5], wherein

[0026] The material constituting the flexible substrate is at least one selected from the group consisting of polyethylene terephthalate, cycloolefin polymer, cycloolefin copolymer, and polycarbonate.

[0027] 〔7〕

[0028] A method for manufacturing a conductive substrate, the conductive substrate comprising a substrate and conductive fine wires containing silver arranged on the substrate, the method for manufacturing the conductive substrate sequentially comprising:

[0029] Step 1, forming a metal-containing layer in the form of a thin line on a substrate; and

[0030] Step 2, performing electroless plating on the metal-containing layer to form the conductive fine wires, wherein the plating solution used in the electroless plating comprises potassium iodide and a reducing agent, the content of the reducing agent in the plating solution is 60 mmol / L or less, and the contents of the potassium iodide and the reducing agent are respectively set to C KI mmol / L and C R mmol / L, satisfying CKI / C R ×1000≤0.7.

[0031] 〔8〕

[0032] The method for producing a conductive substrate according to [7], wherein:

[0033] The electroless plating treatment is electroless silver plating treatment.

[0034] Effects of the Invention

[0035] According to the present invention, a conductive substrate having excellent conductivity and excellent migration suppression performance and a method for producing the conductive substrate can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic perspective view showing an example of the structure of the conductive substrate of the present invention.

[0037] Figure 2 This is a plan view showing an example of a mesh pattern formed by conductive fine wires of the conductive substrate of the present invention. DETAILED DESCRIPTION

[0038] Hereinafter, the conductive substrate of the present invention will be described in detail with reference to the drawings.

[0039] The description of the constituent elements described below is based on typical embodiments of the present invention, but the present invention is not limited to these embodiments.

[0040] The drawings are illustrative drawings for explaining the present invention, and the present invention is not limited to the drawings. In addition, the scale of the components shown in the drawings may be different from the actual scale.

[0041] In this specification, the numerical range represented by "to" refers to a range including the numerical values ​​recorded before and after "to" as the lower limit and the upper limit. In this specification, for each component, one substance corresponding to each component can be used alone, or two or more substances can be used in combination. Here, for each component, when two or more substances are used in combination, unless otherwise specified, the content of the component refers to the total content of the substances used in combination.

[0042] In this specification, "g" and "mg" respectively represent "mass g" and "mass mg".

[0043] In the present specification, "polymer" or "polymer compound" refers to a compound having a weight average molecular weight of 2000 or more. Here, the weight average molecular weight (Mw) is defined as a polystyrene conversion value measured by GPC (Gel Permeation Chromatography).

[0044] In addition, regarding the angle, "orthogonal" or "perpendicular" means the range of 90°±5°, and "parallel" means the range of 0°±5°. Similarly, regarding the angle, unless otherwise specified, it means that the difference from the strict angle is within 5 degrees. The difference of the above angle is preferably within 4 degrees, and more preferably within 3 degrees.

[0045] [Conductive substrate]

[0046] The conductive substrate according to the present invention includes a substrate and conductive thin wires disposed on the substrate and containing silver.

[0047] Figure 1 This is a schematic perspective view showing an example of the conductive substrate according to the present invention.

[0048] The conductive substrate 10 includes a substrate 12 and conductive thin wires 14 disposed on a surface 12a of the substrate 12 and containing silver. Figure 1 In FIG. 2 , two conductive thin wires 14 extending in one direction are shown, but the arrangement form and number of the conductive thin wires 14 are not particularly limited.

[0049] Figure 1 The vertical cross section Ac shown is a cross section obtained when the conductive thin wire 14 is cut on a plane perpendicular to the direction DL in which the conductive thin wire 14 extends. That is, the vertical cross section Ac of the conductive thin wire 14 includes a direction DW perpendicular to the direction DL in which the conductive thin wire 14 extends.

[0050] [Substrate]

[0051] The substrate is not particularly limited as long as it can support the conductive thin wires, and examples thereof include a plastic substrate, a glass substrate, and a metal substrate.

[0052] As the substrate, a flexible substrate is preferred from the viewpoint of excellent bending of the obtained conductive component. As the material constituting the flexible substrate, for example, polyethylene terephthalate (PET), cycloolefin polymer (COP), cycloolefin copolymer (COC) and polycarbonate (PC) can be cited. Among them, PET is preferred from the aspect of excellent adhesion with the conductive fine wire.

[0053] The thickness of the substrate is not particularly limited, but is generally 25 to 500 μm. When the conductive substrate is used in a touch panel and the substrate surface is used as a touch surface, the thickness of the substrate may exceed 500 μm.

[0054] The total light transmittance of the substrate is preferably 85% to 100%. The total light transmittance is measured using "Plastics - Method for determining total light transmittance and total light reflectance" specified in JIS (Japanese Industrial Standards) K 7375:2008.

[0055] A primer layer may be disposed on the surface of the substrate.

[0056] The primer layer preferably contains a specific polymer described below. When the primer layer is used, the adhesion of the conductive thin wires described below to the substrate is further improved.

[0057] The formation method of the primer layer is not particularly limited, for example, a primer layer forming composition comprising a specific polymer described later is applied to a substrate and subjected to a heat treatment as required. The primer layer forming composition may contain a solvent as required. The type of solvent is not particularly limited, and the solvent used in the photosensitive layer forming composition described later can be cited. In addition, as the primer layer forming composition comprising a specific polymer, a latex containing particles of the specific polymer can be used.

[0058] The thickness of the primer layer is not particularly limited, but is preferably 0.02 to 0.3 μm, more preferably 0.03 to 0.2 μm, from the viewpoint of better adhesion of the conductive layer to the substrate.

[0059] 〔Conductive thin wire〕

[0060] Conductive thin wires containing silver are arranged on the surface of the substrate. The conductive thin wires contain silver to ensure the conductive properties of the conductive substrate.

[0061] The conductive thin wires are arranged on the substrate surface. This means that the conductive thin wires may be in direct contact with the substrate surface, or the substrate and the conductive thin wires may be arranged with another layer (for example, the above-mentioned primer layer) interposed therebetween.

[0062] In this specification, the conductive fine wire refers to a fine line region disposed on the surface of the substrate and integrally formed of a material containing silver. For example, a layer not containing silver halide formed by step E described later and a protective layer formed by step F described later together with a fine line-shaped silver-containing layer formed by steps A and B described later constitute the conductive fine wire.

[0063] Furthermore, the conductive thin wires disposed on the surface of the substrate may or may not be electrically connected to external components of the conductive substrate. Part of the conductive thin wires may be dummy electrodes electrically insulated from the outside.

[0064] The conductive thin wire contains silver (metallic silver). The silver contained in the conductive thin wire may be silver alone or a mixture of silver and other metals other than silver. Examples of other metals include copper (metallic copper), gold (metallic gold), nickel (metallic nickel) and palladium (metallic palladium), preferably copper.

[0065] Hereinafter, unless otherwise specified, the term "silver" simply refers to "metallic silver".

[0066] The conductive thin wire is preferably composed of silver alone or a mixture of silver and copper, and is more preferably composed of silver alone from the viewpoint of suppressing the occurrence of disconnection failure of the conductive thin wire.

[0067] The silver contained in the conductive fine wire is usually in the form of particles. The average particle size of the silver particles is preferably 10 to 1000 nm, more preferably 10 to 200 nm, in terms of spherical equivalent diameter. In addition, the spherical equivalent diameter refers to the diameter of spherical particles having the same volume. The average particle size of the silver particles is obtained as the average value obtained by measuring the spherical equivalent diameters of 100 objects and arithmetically averaging them.

[0068] The shape of the silver particles is not particularly limited, and examples thereof include spherical, cubic, flat, octahedral, and tetradecahedral shapes. Furthermore, in the conductive fine wire, the silver may be in a shape other than a particle shape, for example, it may be in a form where it is partially or entirely bonded by welding, or it may be in a form where the silver is dispersed in layers in the conductive fine wire.

[0069] The conductive fine wire may have a structure in which a plurality of silver particles are dispersed in a polymer compound, or may exist in the form of an aggregate in which silver particles are aggregated in the polymer compound. Furthermore, at least a portion of the plurality of silver particles contained in the conductive fine wire may be bonded to each other by a silver plating treatment described later. The above-mentioned polymer compound will be described later.

[0070] <Silver content>

[0071] The silver content in the conductive thin wire is not particularly limited. From the viewpoint of further improving the conductivity of the conductive substrate, the silver content per unit area of ​​the region on the substrate surface where the conductive thin wire is arranged is preferably 0.01 to 10 g / m 2 , more preferably 0.03 to 1 g / m 2 .

[0072] The silver content in the conductive thin wire can be adjusted by, for example, the content of the silver component contained in the composition for forming the conductive thin wire (for example, the silver halide contained in the photosensitive layer forming composition described later) and the amount of silver plating in the plating treatment described later.

[0073] The content of silver in the conductive thin wires can be obtained by measuring the weight of silver contained in the conductive thin wires per unit area of ​​the main surface of the substrate using a fluorescent X-ray measuring device.

[0074] <Ratio of the amount of iodine atoms to the amount of silver atoms (ratio I / Ag)>

[0075] In the conductive thin wire involved in the present invention, the ratio of the amount of iodine atoms to the amount of silver atoms detected when the surface of the conductive thin wire is measured by fluorescent X-ray analysis (hereinafter also referred to as "ratio I / Ag" in this specification) is 0.035 to 0.100.

[0076] The conductive substrate involved in the present invention has a ratio I / Ag of 0.035 to 0.100 on the surface of the conductive fine wire, thereby becoming a conductive substrate with excellent conductivity and excellent migration inhibition performance. Although the details of the reason why the conductive substrate involved in the present invention exerts the above-mentioned excellent effects are unclear, it is speculated as follows. By having an amount of iodine above a specified amount on the surface of the conductive fine wire, the migration of the conductive fine wire can be suppressed. On the other hand, it is speculated that if the amount of iodine present on the surface of the conductive fine wire is too much, the conductivity of the conductive substrate decreases, because the proportion of silver in the conductive fine wire decreases.

[0077] Hereinafter, the statement "the effect of the present invention is more excellent" means that the conductive substrate is excellent in at least one of the migration suppression performance and the conductivity.

[0078] Hereinafter, a method for measuring the ratio I / Ag on the surface of the conductive thin wire by fluorescent X-ray analysis will be described.

[0079] The above ratio I / Ag was measured by repeatedly performing Ar sputtering (2 kV, Ar ions, 2 mm×2 mm) and fluorescent X-ray analysis (XPS, X-ray source: Al Kα, Quantera SXM manufactured by ULVAC-PHI, Inc.) from the surface of the conductive wire on the opposite side to the substrate toward the depth direction.

[0080] The above-mentioned Ar sputtering and fluorescent X-ray analysis are repeatedly performed on the sample of the conductive substrate, and the depth position where the ratio of the number of metal atoms relative to the total number of atoms is 15% or more is defined as the surface of the conductive fine wire, and the depth from this position toward the substrate side is defined as the inside of the conductive fine wire. On this basis, the surface of the conductive fine wire is subjected to fluorescent X-ray analysis, and the above-mentioned ratio I / Ag (iodine atom content / silver atom content) can be calculated based on the measured values ​​of the atomic weight of silver atoms and the atomic weight of iodine atoms.

[0081] In addition, it is presumed that iodine atoms exist on the surface of the conductive thin wire in the form of an iodine-containing compound such as silver iodide or potassium iodide.

[0082] From the viewpoint of further improving the effects of the present invention, the ratio I / Ag on the surface of the conductive thin wire is preferably 0.040 to 0.080.

[0083] The ratio I / Ag on the surface of the conductive fine wire can be adjusted by the amount of iodine compound and reducing agent contained in the plating solution used for the non-electrolytic plating treatment in step W of forming the conductive fine wire by performing the non-electrolytic plating treatment in the manufacturing method of the conductive substrate described later.

[0084] The conductive thin wires may contain a polymer compound in addition to silver and iodine (iodine compound).

[0085] The type of polymer compound contained in the conductive thin wire is not particularly limited, and known polymer compounds can be used. Among them, polymer compounds different from gelatin (hereinafter also described as "specific polymers") are preferred from the viewpoint of being able to form conductive thin wires with better strength.

[0086] The type of the specific polymer is not particularly limited as long as it is different from gelatin, but a polymer that decomposes gelatin described later and is not decomposed by a proteolytic enzyme or an oxidizing agent is preferred.

[0087] As specific polymers, hydrophobic polymers (water-insoluble polymers) can be cited, for example, at least one resin selected from the group consisting of (meth)acrylic resins, styrene resins, vinyl resins, polyolefin resins, polyester resins, polyurethane resins, polyamide resins, polycarbonate resins, polydiene resins, epoxy resins, silicone resins, cellulose polymers and chitosan polymers, or a copolymer formed from monomers constituting these resins.

[0088] Furthermore, the specific polymer preferably has a reactive group that reacts with a cross-linking agent described below.

[0089] The specific polymer is preferably in a particle form. That is, the conductive thin wire preferably includes particles of the specific polymer.

[0090] As the specific polymer, a polymer (copolymer) represented by the following general formula (1) is preferred.

[0091] General formula (1):-(A)x-(B)y-(C)z-(D)w-

[0092] In the general formula (1), A, B, C, and D each represent a repeating unit represented by the following general formulae (A) to (D).

[0093] [Chemical formula 1]

[0094] A: B:

[0095] C: D:

[0096] R 11 represents a methyl group or a halogen atom, preferably a methyl group, a chlorine atom or a bromine atom. p represents an integer of 0 to 2, preferably 0 or 1, and more preferably 0.

[0097] R 12 It represents a methyl group or an ethyl group, preferably a methyl group.

[0098] R 13 represents a hydrogen atom or a methyl group, preferably a hydrogen atom. L represents a divalent linking group, preferably a group represented by the following general formula (2).

[0099] General formula (2): -(CO-X 1 )rX 2 -

[0100] In the general formula (2), X 1 Represents oxygen atom or NR 30 -. Here, R 30 represents a hydrogen atom, an alkyl group, an aryl group or an acyl group, each of which may have a substituent (for example, a halogen atom, a nitro group and a hydroxyl group). 30 , preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms (for example, methyl, ethyl, n-butyl, and n-octyl), or an acyl group (for example, acetyl and benzoyl). 1 , preferably an oxygen atom or -NH-.

[0101] X 2 represents an alkylene group, an arylene group, an alkylenearylene group, an arylenealkylene group or an alkylenearylenealkylene group, and these groups may be interspersed with -O-, -S-, -CO-, -COO-, -NH-, -SO2-, -N(R 31 )-or-N(R 31 )SO2- etc. 31 represents a linear or branched alkyl group having 1 to 6 carbon atoms. 2 , preferably dimethylene, trimethylene, tetramethylene, o-phenylene, m-phenylene, p-phenylene, -CH2CH2OCOCH2CH2- or -CH2CH2OCO(C6H4)-.

[0102] r represents 0 or 1.

[0103] q represents 0 or 1, preferably 0.

[0104] R 14 It represents an alkyl group, an alkenyl group or an alkynyl group, and is preferably an alkyl group having 5 to 50 carbon atoms, more preferably an alkyl group having 5 to 30 carbon atoms, and still more preferably an alkyl group having 5 to 20 carbon atoms.

[0105] R 15 Represents a hydrogen atom, a methyl group, an ethyl group, a halogen atom, or -CH2COOR 16 , preferably a hydrogen atom, a methyl group, a halogen atom or -CH2COOR 16 , more preferably a hydrogen atom, a methyl group or -CH2COOR 16 , and more preferably a hydrogen atom.

[0106] R 16 represents a hydrogen atom or an alkyl group having 1 to 80 carbon atoms, and may be 14 The same or different, R 16 The number of carbon atoms in the moiety is preferably 1-70, more preferably 1-60.

[0107] In the general formula (1), x, y, z and w represent the molar ratio of each repeating unit.

[0108] x is 3 to 60 mol %, preferably 3 to 50 mol %, more preferably 3 to 40 mol %.

[0109] y is 30 to 96 mol %, preferably 35 to 95 mol %, more preferably 40 to 90 mol %.

[0110] z is 0.5 to 25 mol %, preferably 0.5 to 20 mol %, more preferably 1 to 20 mol %.

[0111] w is 0.5 to 40 mol %, preferably 0.5 to 30 mol %.

[0112] In the general formula (1), x is preferably 3 to 40 mol %, y is preferably 40 to 90 mol %, z is preferably 0.5 to 20 mol %, and w is preferably 0.5 to 10 mol %.

[0113] As the polymer represented by the general formula (1), a polymer represented by the following general formula (2) is preferred.

[0114] [Chemical formula 2]

[0115]

[0116] In the general formula (2), x, y, z and w are as defined above.

[0117] The polymer represented by the general formula (1) may contain other repeating units other than the repeating units represented by the above-mentioned general formulae (A) to (D).

[0118] As monomers for forming other repeating units, for example, acrylates, methacrylates, vinyl esters, olefins, crotonates, itaconic acid diesters, maleic acid diesters, fumaric acid diesters, acrylamides, unsaturated carboxylic acids, allyl compounds, vinyl ethers, vinyl ketones, vinyl heterocyclic compounds, glycidyl esters and unsaturated nitriles can be cited. As these monomers, paragraphs 0010 to 0022 of Japanese Patent Gazette No. 3754745 are also described. From the viewpoint of hydrophobicity, acrylates or methacrylates are preferred, and hydroxyalkyl methacrylate or hydroxyalkyl acrylate is more preferred.

[0119] The polymer represented by the general formula (1) preferably contains a repeating unit represented by the general formula (E).

[0120] [Chemical formula 3]

[0121] E:

[0122] In the above formula, L E The group represents an alkylene group, and is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 2 to 6 carbon atoms, and still more preferably an alkylene group having 2 to 4 carbon atoms.

[0123] As the polymer represented by the general formula (1), a polymer represented by the following general formula (3) is particularly preferred.

[0124] [Chemical formula 4]

[0125] General formula (3)

[0126]

[0127] In the above formula, a1, b1, c1, d1 and e1 represent the molar ratio of each repeating unit, a1 represents 3 to 60 (mol%), b1 represents 30 to 95 (mol%), c1 represents 0.5 to 25 (mol%), d1 represents 0.5 to 40 (mol%), and e1 represents 1 to 10 (mol%).

[0128] The preferred range of a1 is the same as the preferred range of x, the preferred range of b1 is the same as the preferred range of y, the preferred range of c1 is the same as the preferred range of z, and the preferred range of d1 is the same as the preferred range of w.

[0129] e1 is 1 to 10 mol %, preferably 2 to 9 mol %, more preferably 2 to 8 mol %.

[0130] The specific polymer can be synthesized with reference to, for example, Japanese Patent No. 3305459 and Japanese Patent No. 3754745.

[0131] The weight average molecular weight of the specific polymer is not particularly limited, but is preferably 1,000 to 1,000,000, more preferably 2,000 to 750,000, and even more preferably 3,000 to 500,000.

[0132] The conductive thin wires may include materials other than the above-mentioned materials as required.

[0133] For example, antistatic agents, nucleation promoters, spectral sensitizing dyes, surfactants, antifogging agents, hardening agents, anti-black spot agents, redox compounds, monomethine compounds, and dihydroxybenzenes described in paragraphs 0220 to 0241 of Japanese Patent Application Laid-Open No. 2009-004348 can also be cited. Furthermore, the conductive fine wires may contain physical development nuclei.

[0134] Furthermore, the conductive thin wire may contain a crosslinking agent for crosslinking the specific polymers. By containing the crosslinking agent, the specific polymers are crosslinked, and the connection between the metals in the conductive thin wire is maintained.

[0135] <Physical properties of conductive thin wire>

[0136] The line width Wa of the conductive thin wire 14 is in the direction DL in which the conductive thin wire 14 extends (reference Figure 1 ) is the maximum length of the area where the metal silver 15 of the conductive fine wire 14 exists in the direction DW orthogonal to the conductive fine wire 14. From the viewpoint of the balance between conductivity and difficulty in visual identification, the line width Wa of the conductive fine wire 14 is preferably greater than 0.1 μm and less than 5.0 μm. Among them, from the viewpoint of difficulty in visually identifying the conductive fine wire 14, the line width Wa is more preferably less than 2.5 μm, and further preferably less than 2.0 μm. There is no particular restriction on the lower limit, and from the viewpoint of better conductivity of the conductive fine wire, it is preferably greater than 0.5 μm, and more preferably greater than 1.2 μm.

[0137] The line width Wa of the conductive thin wire 14 is obtained by selecting five arbitrary locations corresponding to the line width of one conductive thin wire using a scanning electron microscope and calculating the arithmetic mean of the line widths of the five locations.

[0138] The height T of the conductive fine wires is the maximum length of the region where the metal silver 15 of the conductive fine wires 14 exists in the direction perpendicular to the surface 12a of the substrate 12. The height T of the conductive fine wires 14 is not particularly limited, but is preferably 0.06 μm or more and less than 7.5 μm, and more preferably 0.3 to 3.0 μm, from the viewpoint of the balance between conductivity and flexibility.

[0139] The height T of the conductive thin wire 14 is obtained by selecting five arbitrary locations corresponding to the height of one conductive thin wire using a scanning electron microscope and calculating the arithmetic mean of the heights of the five locations.

[0140] From the viewpoint of the conductivity of the conductive fine wire 14 and the difficulty in preventing the wire from breaking due to the influence of the surface pressure of the roller, the ratio of the height T of the conductive fine wire 14 on the vertical section Ac to the line width Wa of the conductive fine wire 14 (aspect ratio) is preferably 0.3 to 2.5, more preferably greater than 0.6 and less than 1.5, and further preferably greater than 0.8 and less than 1.3.

[0141] The line resistance value of the conductive thin wire is preferably less than 100 Ω / mm, more preferably less than 80 Ω / mm, and further preferably less than 60 Ω / mm from the viewpoint of operability when used as a touch panel.

[0142] The wire resistance value is a value obtained by dividing the resistance value measured by the four-probe method by the distance between the measurement terminals. A more specific method for measuring the wire resistance value is described in the examples described below.

[0143] The conductive thin wires may form a predetermined pattern. That is, the conductive substrate may have a pattern formed by the conductive thin wires.

[0144] The pattern formed by the conductive fine wires is not particularly limited, and examples thereof include triangles such as equilateral triangles, isosceles triangles and right triangles, squares, rectangles, rhombuses, quadrilaterals such as parallelograms and trapezoids, (regular) hexagons, (regular) n-gons such as (regular) octagons, circles, ellipses, stars, and geometric figures formed by combining these figures.

[0145] Furthermore, the pattern formed by the conductive thin wires is more preferably in a mesh shape (mesh pattern).

[0146] Figure 2 This is a plan view showing an example of a mesh pattern formed by conductive fine wires of the conductive substrate according to the present invention.

[0147] like Figure 2 As shown, the grid shape refers to a shape including a plurality of openings (grids) 18 formed by intersecting conductive thin wires 14B. The conductive thin wires 14B have the same structure as the conductive thin wires 14 described above.

[0148] exist Figure 2In the figure, the opening 18 has a rhombus (square) shape, but it can also be other shapes. For example, it can be set to a polygon (for example, a triangle, a quadrilateral, a hexagon and an irregular polygon). And, in addition to a straight line, the shape of one side can also be set to a curved shape, or it can be set to an arc shape. In the case of setting it to an arc shape, for example, the two opposite sides can be set to an arc shape that bulges outward, and the other two opposite sides can be set to an arc shape that bulges inward. And, the shape of each side can also be set to a wavy line shape of a continuous arc bulging outward and an arc bulging inward. Of course, the shape of each side can also be set to a sine curve.

[0149] The length L of one side of the opening 18 is not particularly limited, but is preferably 1500 μm or less, more preferably 1300 μm or less, and further preferably 1000 μm or less. Furthermore, the length L of one side of the opening 18 is preferably 5 μm or more, more preferably 30 μm or more, and further preferably 80 μm or more. When the length of the side of the opening is within the above range, the transparency can be further well maintained, and when the conductive substrate is mounted on the front surface of the display device, the display can be visually recognized without any sense of disobedience.

[0150] From the viewpoint of visible light transmittance, the opening ratio of the mesh pattern is preferably 90.00% or more, more preferably 95.00% or more, and further preferably 99.50% or more. The upper limit is not particularly limited, but may be less than 100%.

[0151] The aperture ratio corresponds to the ratio of the area on the substrate excluding the area where the conductive thin wires are located in the mesh pattern area to the entire area.

[0152] [Method for producing conductive substrate]

[0153] Next, a method for producing the conductive substrate will be described.

[0154] The method for producing the conductive substrate is not particularly limited as long as the conductive substrate having the above-mentioned structure can be produced. For example, a method including the following steps 1 and 2 in order can be mentioned.

[0155] Step 1: Step of forming a thin line-shaped metal-containing layer on a substrate

[0156] Step 2: A step of subjecting the metal-containing layer to electroless plating to form conductive thin wires

[0157] In the above manufacturing method, for example, conductive thin wires containing silver can be formed by performing at least one of step 1a of forming a thin wire-shaped silver-containing layer containing silver as a thin wire-shaped metal-containing layer and step 2a of subjecting the metal-containing layer to electroless silver plating.

[0158] Hereinafter, the steps of each process will be described in detail.

[0159] [Process 1]

[0160] Step 1 is a step of forming a thin-line metal-containing layer on a substrate. In this step, a thin-line metal-containing layer to be subjected to a plating treatment is formed.

[0161] The substrate used in this step is as described above.

[0162] Examples of the metal include silver, copper, gold, nickel and palladium, preferably silver or copper, more preferably silver. That is, step 1 is preferably step 1a of forming a thin line-shaped silver-containing layer containing silver as the thin line-shaped metal-containing layer.

[0163] The metal may be in the form of particles. In this case, the average particle size of the metal particles (preferably silver particles) is preferably 10 to 1000 nm, more preferably 10 to 200 nm, and even more preferably 50 to 150 nm in terms of spherical equivalent diameter.

[0164] The shape of the metal particles is not particularly limited, and examples thereof include spherical, cubic, flat (hexagonal, triangular, quadrilateral, etc.) flat, octahedral, and tetradecahedral shapes.

[0165] The content of the metal in the thin wire is not particularly limited, but is preferably 3.0 to 20.0 g / m 2 .

[0166] The thin wire-shaped metal-containing layer preferably contains a polymer. That is, in the thin wire-shaped metal-containing layer, it is preferred that the polymer is used as a binder and the metal is dispersed in the polymer.

[0167] The type of polymer is not particularly limited, but a specific polymer is preferred from the viewpoint of being able to form a conductive thin wire having a higher strength. The preferred aspects of the specific polymer are also as described above.

[0168] The content of the polymer in the thin wire-shaped metal-containing layer is not particularly limited, but is preferably 0.005 to 2.0 g / m 2 , more preferably 0.01 to 1.0 g / m 2 .

[0169] The method for forming the thin-line metal-containing layer on the substrate is not particularly limited, and a known method can be used. For example, there can be mentioned a method of performing exposure and development using silver halide, a method of forming a thin-line silver-containing layer by forming a layer containing silver on the entire surface of the substrate and then removing a portion of the layer using a resist pattern, and a method of forming a thin-line metal-containing layer by ejecting a composition containing metal particles and a polymer onto a substrate by a known printing method such as inkjet.

[0170] Among them, the method of performing exposure and development using a silver halide is preferred from the viewpoint of being able to produce a conductive substrate that is more excellent in the effect of the present invention.

[0171] The method of exposure and development using silver halide preferably includes the following steps.

[0172] Step A: forming a silver halide-containing photosensitive layer including silver halide, gelatin and a specific polymer on a substrate

[0173] Step B: A step of exposing a photosensitive layer containing silver halide and then developing it to form a thin line-shaped silver-containing layer containing metallic silver, gelatin and a specific polymer.

[0174] Step C: a step of heating the silver-containing layer obtained in step B

[0175] Step D: a step of removing gelatin from the silver-containing layer obtained in step C to form the above-mentioned thin line-shaped silver-containing layer

[0176] Hereinafter, the steps of each process will be described in detail.

[0177] <Process A>

[0178] Step A is a step of forming a silver halide-containing photosensitive layer (hereinafter also referred to as "photosensitive layer") containing silver halide, gelatin and a specific polymer on a substrate. This step produces a substrate with a photosensitive layer to be subjected to an exposure treatment described later.

[0179] First, the materials used in step A are described in detail, and then the steps of step A are described in detail.

[0180] (Silver Halide)

[0181] The halogen atom contained in the silver halide can be any one of a chlorine atom, a bromine atom, an iodine atom and a fluorine atom, or a combination thereof. For example, preferably, a silver halide based on silver chloride, silver bromide or silver iodide is used as the main component, and more preferably, a silver halide based on silver chloride or silver bromide is used as the main component. In addition, silver chlorobromide, silver iodochlorobromide or silver iodobromide can also be preferably used.

[0182] Here, for example, "silver halide mainly composed of silver chloride" refers to a silver halide in which the molar fraction of chloride ions in the total halide ions in the silver halide composition is 50% or more. The silver halide mainly composed of silver chloride may contain bromide ions and / or iodide ions in addition to chloride ions.

[0183] Silver halide is usually in the form of solid particles, and the average particle size of the silver halide is preferably 10 to 1000 nm, more preferably 10 to 200 nm, and further preferably 50 to 150 nm in terms of spherical equivalent diameter.

[0184] The shape of the silver halide particles is not particularly limited, and examples thereof include spherical, cubic, flat (hexagonal, triangular, quadrilateral, etc.), octahedral, and tetradecahedral shapes.

[0185] (gelatin)

[0186] The type of gelatin is not particularly limited, and examples thereof include lime-treated gelatin and acid-treated gelatin. In addition, gelatin hydrolysates, gelatin enzymatic decomposition products, and gelatin modified with amino groups and / or carboxyl groups (phthalated gelatin and acetylated gelatin) can be used.

[0187] (Specific polymer)

[0188] The photosensitive layer contains a polymer (specific polymer) different from gelatin. By containing the specific polymer in the photosensitive layer, the strength of the silver-containing layer and the conductive thin wire formed by the photosensitive layer is further improved.

[0189] The characteristics such as the type, specific example and shape of the specific polymer are as described above.

[0190] The photosensitive layer may contain materials other than the above-mentioned materials as required.

[0191] As other materials, for example, metal compounds belonging to Group 8 and Group 9, such as rhodium compounds and iridium compounds, which are used for stabilization and high sensitivity of silver halide, can be cited. In addition, as other materials, other materials that can be included in the above-mentioned conductive thin wires can be cited.

[0192] Materials other than these gelatin and specific polymers may be contained in the layer not containing silver halide and / or the protective layer described later.

[0193] (Steps of Process A)

[0194] The method for forming the photosensitive layer containing the above-mentioned components in step A is not particularly limited. From the viewpoint of productivity, a method in which a photosensitive layer-forming composition containing silver halide, gelatin and a specific polymer is brought into contact with a substrate to form the photosensitive layer on the substrate is preferred.

[0195] (Materials contained in the photosensitive layer forming composition)

[0196] The composition for forming a photosensitive layer contains the above-mentioned silver halide, gelatin and a specific polymer. In addition, the specific polymer may be contained in the composition for forming a photosensitive layer in the form of particles as required.

[0197] The photosensitive layer-forming composition may contain a solvent as needed.

[0198] Examples of the solvent include water, organic solvents (for example, alcohols, ketones, amides, sulfoxides, esters, and ethers), ionic liquids, and mixed solvents thereof.

[0199] The method of bringing the photosensitive layer-forming composition into contact with the substrate is not particularly limited, and examples thereof include a method of applying the photosensitive layer-forming composition on the substrate and a method of immersing the substrate in the photosensitive layer-forming composition.

[0200] Furthermore, after the above treatment, a drying treatment may be performed as necessary.

[0201] (Photosensitive layer containing silver halide)

[0202] The photosensitive layer formed through the above steps contains silver halide, gelatin and a specific polymer.

[0203] The content of the silver halide in the photosensitive layer is not particularly limited, but is preferably 3.0 to 20.0 g / m2 in terms of silver from the viewpoint of achieving a more excellent effect of the present invention. 2 , more preferably 5.0 to 15.0 g / m 2 .

[0204] The silver conversion refers to the mass of silver produced by the reduction of all silver halides.

[0205] The content of the specific polymer in the photosensitive layer is not particularly limited, but is preferably 0.04 to 2.0 g / m 2 , more preferably 0.08 to 0.40 g / m 2 .

[0206] <Process B>

[0207] Step B is a step of exposing the photosensitive layer and then performing a development treatment to form a thin line-shaped silver-containing layer containing metallic silver, gelatin, and a specific polymer.

[0208] By subjecting the photosensitive layer to exposure processing, a latent image is formed in the exposed area.

[0209] The exposure may be performed in a pattern. For example, in order to obtain a grid pattern composed of the above-mentioned conductive fine wires, there can be mentioned a method of performing exposure through a mask having a grid-like opening pattern and a method of performing exposure in a grid pattern by scanning a laser beam.

[0210] The type of light used for exposure is not particularly limited as long as it can form a latent image on the silver halide, and examples thereof include visible light, ultraviolet light, and X-rays.

[0211] In the case of exposing through a mask having an opening pattern, the amount of latent image formation can be adjusted by reducing the exposure amount and exposing only a specific position in the mask opening pattern. If the amount of latent image formation is adjusted, the amount of metal and thickness (height) formed in subsequent operations can be adjusted. There is no particular limitation on the method of reducing the exposure amount only for a specific position, for example, a method of adjusting the exposure amount from a light source irradiated to a specific part can be cited. For example, methods such as reducing the exposure amount by only reducing the output of a lamp or LED on the part or providing a dimming filter on the upper part of a specific part can be cited. And, as another method of reducing the exposure amount only for a specific position, a method of using a halftone mask that imparts a semi-transmissive film to a specific part of the mask opening pattern can be cited. From the viewpoint of productivity, it is preferred to use a halftone mask.

[0212] By subjecting the exposed photosensitive layer to a development process, metallic silver is precipitated in the exposed region (region where the latent image is formed).

[0213] The method of the development treatment is not particularly limited, and examples thereof include known methods used in silver salt photographic films, photographic papers, films for printing plate making, and emulsion masks for photomasks.

[0214] A developer is generally used in the development treatment. The type of the developer is not particularly limited, and examples thereof include PQ (phenidone hydroquinone) developer, MQ (metol hydroquinone) developer, and MAA (metol ascorbic acid) developer.

[0215] This step may further include a fixing treatment for the purpose of removing the silver halide in the unexposed portion to stabilize it.

[0216] The fixing treatment is performed simultaneously with the development and / or after the development. The fixing treatment method is not particularly limited, and examples thereof include methods used in silver salt photographic films, printing papers, films for printing plates, and latex masks for photomasks.

[0217] A fixing solution is generally used in the fixing process. The type of the fixing solution is not particularly limited, and examples thereof include the fixing solutions described in "The Chemistry of Photography" (written by Sasai, published by Photo Industry Publishing Co., Ltd.), p. 321.

[0218] By performing the above treatment, a thin line-shaped silver-containing layer containing metallic silver, gelatin, and a specific polymer can be formed.

[0219] As a method of adjusting the width of the silver-containing layer, for example, there is a method of adjusting the opening width of a mask used in exposure.

[0220] Furthermore, when a mask is used during exposure, the width of the formed silver-containing layer can be adjusted by adjusting the exposure amount. For example, when the opening width of the mask is narrower than the target width of the silver-containing layer, the width of the area where the latent image is formed can be adjusted by increasing the exposure amount compared to normal.

[0221] Furthermore, in the case of using a laser beam, the exposure area can be adjusted by adjusting the focusing range and / or scanning range of the laser beam.

[0222] <Process C>

[0223] Step C is a step of subjecting the silver-containing layer obtained in step B to a heat treatment. By carrying out this step, the specific polymers in the silver-containing layer are fused together, thereby improving the strength of the silver-containing layer.

[0224] The method of heat treatment is not particularly limited, and examples thereof include a method of contacting the silver-containing layer with superheated steam and a method of heating the silver-containing layer using a temperature control device (eg, a heater). Preferably, the silver-containing layer is contacted with superheated steam.

[0225] The superheated steam may be superheated water steam, or other gas may be mixed in the superheated water steam.

[0226] The contact time between the superheated steam and the silver-containing layer is not particularly limited, but is preferably 10 to 70 seconds.

[0227] The supply rate of superheated steam is preferably 500 to 600 g / m 3 The temperature of the superheated steam is preferably 100 to 160° C., more preferably 100 to 120° C. at 1 atmosphere.

[0228] As heating conditions in the method of heating the silver-containing layer using a temperature control device, heating at 100 to 200° C. (more preferably 100 to 150° C.) for 1 to 240 minutes (more preferably 60 to 150 minutes) is preferred.

[0229] <Process D>

[0230] Step D is a step of removing gelatin from the silver-containing layer obtained in step C to form a thin line-shaped silver-containing layer. By performing this step, gelatin is removed from the silver-containing layer to form the thin line-shaped silver-containing layer having voids formed therein. A plating treatment solution described later penetrates into the voids to form a metal plated layer.

[0231] When removing the gelatin, all of the gelatin in the silver-containing layer may be removed, or the gelatin may be removed while a portion of the gelatin remains.

[0232] The method for removing gelatin is not particularly limited, and examples thereof include a method using a proteolytic enzyme (hereinafter also referred to as "method 1") and a method using an oxidizing agent to decompose and remove gelatin (hereinafter also referred to as "method 2").

[0233] Examples of the proteolytic enzyme used in method 1 include known plant or animal enzymes that can hydrolyze proteins such as gelatin.

[0234] Examples of the proteolytic enzyme include pepsin, rennet, trypsin, chymotrypsin, cathepsin, papain, ficin, thrombin, renin, collagenase, bromelain, and bacterial proteases, and preferably trypsin, papain, ficin, or bacterial proteases.

[0235] The step in method 1 may be any method as long as it is a method of contacting the silver-containing layer with the above-mentioned proteolytic enzyme, and for example, a method of contacting the silver-containing layer with a treatment solution containing a proteolytic enzyme (hereinafter also referred to as "enzyme solution") can be mentioned. As the contact method, a method of immersing the silver-containing layer in the enzyme solution and a method of coating the silver-containing layer with the enzyme solution can be mentioned.

[0236] The content of the proteolytic enzyme in the enzyme solution is not particularly limited, but is preferably 0.05 to 20% by mass, more preferably 0.5 to 10% by mass, based on the total amount of the enzyme solution, from the viewpoint of easily controlling the degree of decomposition and removal of gelatin.

[0237] The enzyme solution generally contains water in addition to the above-mentioned proteolytic enzyme.

[0238] The enzyme solution may contain other additives (eg, pH buffers, antimicrobial compounds, wetting agents, and preservatives) as needed.

[0239] The pH of the enzyme solution is selected so as to maximize the action of the enzyme, and is usually preferably 5 to 9.

[0240] The temperature of the enzyme solution is preferably a temperature at which the action of the enzyme is enhanced, specifically, 20 to 45°C.

[0241] Furthermore, if necessary, after the treatment with the enzyme solution, the obtained silver-containing layer may be subjected to a cleaning treatment with warm water.

[0242] The cleaning method is not particularly limited, but a method of bringing the silver-containing layer into contact with warm water is preferred. Examples of the method include a method of immersing the silver-containing layer in warm water and a method of applying warm water on the silver-containing layer.

[0243] The temperature of the warm water can be appropriately selected to an optimal temperature depending on the type of proteolytic enzyme used, but is preferably 20 to 80°C, more preferably 40 to 60°C, from the viewpoint of productivity.

[0244] The contact time (cleaning time) of the warm water and the silver-containing layer is not particularly limited, but is preferably 1 to 600 seconds, more preferably 10 to 180 seconds, from the viewpoint of productivity.

[0245] The oxidant used in method 2 may be any oxidant capable of decomposing gelatin, and preferably has a standard electrode potential of +1.5 V or higher. The standard electrode potential here refers to the standard electrode potential of the oxidant in aqueous solution relative to a standard hydrogen electrode (25° C., E0).

[0246] As the above-mentioned oxidizing agent, for example, persulfuric acid, percarbonic acid, perphosphoric acid, hypoperchloric acid (HClO5), peracetic acid, m-chloroperbenzoic acid, hydrogen peroxide solution, perchloric acid, periodic acid, potassium permanganate, ammonium persulfate, ozone, hypochlorous acid or its salt, etc. Among them, hydrogen peroxide solution (standard electrode potential: 1.76V), hypochlorous acid or its salt are preferred, and sodium hypochlorite is more preferred from the viewpoint of productivity and economy.

[0247] As the step in method 2, any method may be used as long as it is a method of contacting the silver-containing layer with the above-mentioned oxidant, for example, a method of contacting the silver-containing layer with a treatment solution containing an oxidant (hereinafter also referred to as "oxidant solution") can be mentioned. As the contact method, a method of immersing the silver-containing layer in the oxidant solution and a method of coating the silver-containing layer with the oxidant solution can be mentioned.

[0248] The type of the solvent contained in the oxidizing agent liquid is not particularly limited, and examples thereof include water and organic solvents.

[0249] <Process E>

[0250] Step 1 may include step E of forming a layer containing no silver halide and gelatin and a specific polymer on the substrate before step A. By implementing this step, a layer containing no silver halide is formed between the substrate and the photosensitive layer containing silver halide. The layer containing no silver halide plays the role of a so-called anti-halation layer and helps to improve the adhesion between the conductive fine wire and the substrate.

[0251] The layer not containing silver halide contains the gelatin and the specific polymer described above. On the other hand, the layer not containing silver halide does not contain silver halide.

[0252] The ratio of the mass of the specific polymer to the mass of gelatin in the layer containing no silver halide (mass of specific polymer / mass of gelatin) is not particularly limited, but is preferably 0.1 to 5.0, and more preferably 1.0 to 3.0.

[0253] The content of the specific polymer in the layer not containing silver halide is not particularly limited, but is usually 0.03 g / m 2 From the viewpoint of better adhesion of the conductive thin wire, 1.0 g / m 2 There is no particular upper limit, but it is usually 1.63 g / m 2 the following.

[0254] The method for forming the layer not containing silver halide is not particularly limited, and examples thereof include a method in which a layer-forming composition containing gelatin and a specific polymer is applied on a substrate and then subjected to a heat treatment as necessary.

[0255] The layer-forming composition may contain a solvent as necessary. As the type of the solvent, the solvent used in the above-mentioned photosensitive layer-forming composition can be exemplified.

[0256] The thickness of the layer not containing silver halide is not particularly limited, but is usually 0.05 μm or more, preferably more than 1.0 μm, more preferably 1.5 μm or more, from the viewpoint of better adhesion of the conductive thin wires. The upper limit is not particularly limited, but is preferably less than 3.0 μm.

[0257] <Process F>

[0258] Step 1 may include step F of forming a protective layer containing gelatin and a specific polymer on the photosensitive layer containing silver halide after step A and before step B. By providing the protective layer, it is possible to prevent scratches on the photosensitive layer and improve mechanical properties.

[0259] The ratio of the mass of the specific polymer to the mass of gelatin in the protective layer (mass of specific polymer / mass of gelatin) is not particularly limited, but is preferably greater than 0 and less than 2.0, and more preferably greater than 0 and less than 1.0.

[0260] Furthermore, the content of the specific polymer in the protective layer is not particularly limited, but is preferably more than 0 g / m 2 And 0.3g / m 2 Below, more preferably 0.005 to 0.1 g / m 2 .

[0261] The method for forming the protective layer is not particularly limited, and examples thereof include a method in which a protective layer-forming composition containing gelatin and a specific polymer is applied onto a photosensitive layer containing silver halide and then subjected to a heat treatment as necessary.

[0262] The protective layer forming composition may contain a solvent as needed. As the type of the solvent, the solvent used in the above-mentioned photosensitive layer forming composition can be exemplified.

[0263] The thickness of the protective layer is not particularly limited, but is preferably 0.03 to 0.3 μm, more preferably 0.075 to 0.20 μm.

[0264] In addition, the above-mentioned step E, step A, and step F can be simultaneously performed by simultaneous multi-layer coating.

[0265] (Process G)

[0266] The method for manufacturing a conductive substrate preferably includes a step G of contacting a thin wire-shaped metal-containing layer (hereinafter also referred to as "thin wire") formed on the substrate by step 1 with a solution containing an organic acid after step 1 and before step 2. Through step G, the organic acid adheres to the surface of the thin wire, and the plating layer on the surface of the thin wire is suppressed during the plating treatment of step 2 described later, and the plating treatment solution is more likely to penetrate into the inside of the thin wire. As a result, the metal (metal plating) is easily precipitated in the thin wire, and the desired effect can be obtained.

[0267] (Solution containing organic acid)

[0268] The type of organic acid contained in the solution containing an organic acid (hereinafter, also referred to as "the first solution") is not particularly limited as long as it is an acid containing a carbon atom, and examples thereof include carboxylic acid (an organic compound having a carboxyl group), sulfonic acid (an organic compound having a sulfonic acid group), and phosphonic acid (an organic compound having a phosphonic acid group). Among them, carboxylic acid is preferred.

[0269] The molecular weight of the organic acid (eg, carboxylic acid) is not particularly limited, but is preferably 60 to 400, more preferably 90 to 300.

[0270] The carboxylic acid may be a monovalent carboxylic acid or a divalent or higher (polyvalent) carboxylic acid, and a polyvalent carboxylic acid is preferred. As the divalent or higher carboxylic acid, a divalent to heptavalent carboxylic acid is preferred, and a divalent to tetravalent carboxylic acid is more preferred.

[0271] In addition, the above-mentioned valence number indicates the number including the carboxyl group, and a monovalent carboxylic acid is a compound having one carboxyl group.

[0272] The carboxylic acid may have other polar groups (eg, hydroxyl group, amino group, carboxyl group, ether group) in addition to the carboxyl group.

[0273] Examples of the carboxylic acid include monovalent carboxylic acids such as acetic acid, lactic acid, and hydroxybutyric acid; divalent carboxylic acids such as oxalic acid, malonic acid, tartaric acid, L-aspartic acid, DL-malic acid, oxaloacetic acid, succinic acid, glutamic acid, 2-ketoglutaric acid, glutaric acid, adipic acid, and pimelic acid; trivalent carboxylic acids such as citric acid, 1,2,3-propanetricarboxylic acid, and 1,3,5-pentanetricarboxylic acid; tetravalent carboxylic acids such as 1,2,3,4-butanetetracarboxylic acid, ethylenediaminetetraacetic acid, and ethylene glycol bis(β-aminoethyl ether)-N,N,N,N-tetraacetic acid; and pentavalent carboxylic acids such as diethylenetriaminepentaacetic acid.

[0274] The first solution contains a solvent. The type of the solvent is not particularly limited, and examples thereof include water, organic solvents (for example, alcohols, ketones, amides, sulfoxides, esters, and ethers), ionic liquids, and mixed solvents thereof. Among them, water is preferred.

[0275] The content of the organic acid in the first solution is not particularly limited, but is preferably 0.2 to 5% by mass, more preferably 0.5 to 3% by mass, based on the total mass of the first solution.

[0276] The pH value of the first solution is not particularly limited, but is preferably 1.5 to 6.0, more preferably 2.0 to 4.0 at a temperature of 25°C.

[0277] As a method for measuring pH, it can be measured with a pH meter using a pH electrode.

[0278] (Steps of process G)

[0279] The method of bringing the thin wires into contact with the first solution is not particularly limited, and examples thereof include a method of immersing a substrate having the thin wires in the first solution and a method of coating the first solution on the thin wires.

[0280] The contact time between the thin wire and the first solution is not particularly limited, but is preferably 5 to 180 seconds, more preferably 20 to 120 seconds, from the viewpoint of productivity.

[0281] The temperature of the first solution when the thin wire is in contact with the first solution is not particularly limited, but is preferably 30 to 100°C, and more preferably 65 to 95°C.

[0282] After the thin wire is brought into contact with the first solution, the thin wire may be washed with a solvent (eg, water) as necessary.

[0283] [Process 2]

[0284] Step 2 is a step of forming conductive thin wires by subjecting the above-mentioned thin wire-shaped metal-containing layer to electroless plating. By carrying out this step, metal is precipitated on the surface and inside of the thin wire-shaped metal-containing layer. In particular, in the thin wire-shaped silver-containing layer obtained by carrying out the above-mentioned steps A to D, there is a space formed by removing gelatin, so conductive thin wires filled with metal are formed in the space.

[0285] As the electroless plating treatment performed in this step, a known electroless plating technique (chemical reduction plating or displacement plating) can be used. As the electroless plating treatment, a known electroless plating technique can be used.

[0286] Examples of the metal species used for the plating treatment include silver, copper, nickel, and cobalt. From the viewpoint of achieving more excellent effects of the present invention, silver or copper is preferred, and silver is more preferred.

[0287] That is, as step 2 of subjecting the metal-containing layer to electroless plating, from the viewpoint of achieving more excellent effects of the present invention, it is preferred to subject the metal-containing layer to electroless silver plating or electroless copper plating, and it is more preferred to subject the metal-containing layer to electroless silver plating 2a.

[0288] <Plating treatment solution>

[0289] Examples of a plating solution (hereinafter, also simply referred to as a “plating solution”) used in the electroless plating treatment include a plating solution containing a solvent, metal ions, a reducing agent, and potassium iodide.

[0290] As the solvent contained in the plating solution, water is preferred.

[0291] The content of the solvent in the plating solution is not particularly limited, but is preferably 60 to 95% by mass, more preferably 80 to 90% by mass, relative to the total mass of the plating solution.

[0292] The type of metal ions contained in the plating solution can be appropriately selected according to the type of metal to be precipitated, and examples thereof include silver ions, copper ions, nickel ions, and cobalt ions. Silver ions or copper ions are preferred, and silver ions are more preferred.

[0293] The metal ions in the plating solution are derived from, for example, a metal salt added to the plating solution. The type of the metal salt added to the plating solution is not particularly limited, and a known metal salt can be used.

[0294] The metal salt is preferably a water-soluble metal salt. The water-soluble metal salt refers to a metal salt that dissolves in water at 0.1% by mass or more.

[0295] As the metal salt, a silver salt or a copper salt is preferred, and a silver salt is more preferred.

[0296] Examples of the silver salt include inorganic silver salts and organic silver salts, and inorganic silver salts are preferred.

[0297] Examples of the inorganic silver salt include silver nitrate, silver fluoride, silver perchlorate, and silver sulfate.

[0298] The content of the silver salt in the plating solution is not particularly limited, but is preferably 0.01 to 5.0 mol / L, more preferably 0.05 to 3.0 mol / L, relative to the total amount of the plating solution.

[0299] The silver salt may be used alone or in combination of two or more.

[0300] In addition, silver contained in the silver salt is ionized in the plating solution to become silver ions.

[0301] The type of the reducing agent contained in the plating solution is not particularly limited, and a known reducing agent can be used.

[0302] Examples of the reducing agent include ascorbic acid compounds such as ascorbic acid and isoascorbic acid, or salts thereof; hydrazine such as hydrazine, hydrazine monohydrate, hydrazine sulfate, and hydrazine chloride, or salts thereof; hydroquinone such as hydroquinone and methylhydroquinone, or derivatives thereof; and pyrogallol such as pyrogallol, pyrogallol monomethyl ether, pyrogallol-4-carboxylic acid, pyrogallol-4,6-dicarboxylic acid, and gallic acid, or derivatives thereof.

[0303] The content of the reducing agent in the plating solution is not particularly limited, but is preferably 2 mol / L or less, more preferably 0.1 mol / L or less, and further preferably 0.06 mol / L (60 mmol / L) or less relative to the total amount of the plating solution. The lower limit is not particularly limited, but is preferably 0.01 mol / L (10 mmol / L) or more, and more preferably 0.02 mol / L (20 mmol / L) or more relative to the total amount of the plating solution.

[0304] The reducing agent may be used alone or in combination of two or more.

[0305] The plating solution used for the electroless plating treatment contains potassium iodide.

[0306] The content of potassium iodide in the plating solution is, for example, preferably 0.001 to 1 mmol / L, more preferably 0.01 to 0.1 mmol / L, relative to the total amount of the plating solution.

[0307] Furthermore, from the viewpoint of making it easier to form conductive thin wires having a ratio I / Ag within the above range, when the content of potassium iodide in the plating solution is set to C KI mmol / L and the content of the reducing agent in the plating solution is set to C Rmmol / L, the ratio C calculated by the following formula (1) is preferably less than 5, more preferably less than 1, further preferably less than 0.8, and particularly preferably less than 0.7. The lower limit of the ratio C is not particularly limited, but is preferably 0.01 or more, more preferably 0.1 or more, and further preferably 0.3 or more.

[0308] Ratio C = C KI / C R ×1000(1)

[0309] In particular, as a plating solution for electroless plating, from the viewpoint of making it easier to form conductive thin wires with a ratio I / Ag within the above range, it is preferred that the plating solution comprises potassium iodide and a reducing agent, the content of the reducing agent in the plating solution is 60 mmol / L or less relative to the total amount of the plating solution, and the contents of potassium iodide and the reducing agent in the plating solution are respectively C KI mmol / L and C R mmol / L, the ratio C=C KI / C R ×1000≤0.7. The preferred ranges of the lower limit of the content of the reducing agent, the content of potassium iodide, and the lower limit of the ratio C are as described above.

[0310] It is preferable to adjust the content of potassium iodide and / or the reducing agent in the plating treatment solution for electroless plating treatment so as to be within the above-mentioned preferred range of content.

[0311] The plating solution may contain other components in addition to the above components. Examples of other components include stabilizers and pH adjusters that improve the stability of silver ions ionized from the silver salt.

[0312] The pH of the plating solution is not particularly limited, but is preferably alkaline, more preferably 8.5 to 11.0, and even more preferably 9.0 to 10.5 at a temperature of 25° C. from the viewpoint of achieving more excellent effects of the present invention.

[0313] <Plating process>

[0314] The plating treatment procedure is not particularly limited as long as the metal-containing layer is brought into contact with the plating solution. Examples thereof include a method of immersing the metal-containing layer in the plating solution and a method of coating the metal-containing layer with the plating solution.

[0315] The contact time between the metal-containing layer and the plating solution is not particularly limited, but is preferably 25 seconds to 30 minutes from the viewpoint of achieving more excellent effects of the present invention and productivity.

[0316] After contact with the plating solution, the metal-containing layer can be washed with water or neutralized and washed with an acidic solution of pH 3 to 7. The pH of the acidic solution used for neutralization and washing is preferably 4 to 6. If the pH of the acidic solution is 3 to 7, sulfur and the like will not be generated from sulfurous acid derived from the plating solution. In addition, the rise in the pH of the plating solution can be suppressed, and the plating reaction can be stopped. The acidic solution acts as a plating stop solution.

[0317] The acidic solution preferably has a buffering effect, and a solid content concentration of 0.1% by mass or more is preferred because sufficient buffering capacity is exhibited.

[0318] The temperature of the plating solution is preferably 10 to 40°C, more preferably 15 to 30°C.

[0319] The contact time is not particularly limited, but is preferably 5 to 60 seconds from the viewpoint of achieving more excellent effects of the present invention and productivity.

[0320] 〔Other processes〕

[0321] The method for producing a conductive substrate may include other steps in addition to the above-mentioned step 1 and step 2.

[0322] <Process 3>

[0323] The method for producing a conductive substrate may include step 3 of further subjecting the conductive thin wires obtained in the above steps to a smoothing treatment.

[0324] By carrying out this step, conductive thin wires having more excellent conductivity can be obtained.

[0325] The method of the smoothing treatment is not particularly limited, and for example, it is preferable to pass the substrate having the conductive thin wires through a calendering treatment step between at least a pair of rollers under pressure. Hereinafter, the smoothing treatment using calendering rollers is referred to as calendering treatment.

[0326] Examples of the roll used for the calendering treatment include a plastic roll and a metal roll. From the viewpoint of preventing wrinkles, a plastic roll is preferred.

[0327] The pressure between the rollers is not particularly limited, but is preferably 2 MPa or more, more preferably 4 MPa or more. Furthermore, the pressure between the rollers is preferably 120 MPa or less. In addition, the pressure between the rollers can be measured using Prescale (for high pressure) manufactured by Fujifilm Corporation.

[0328] The temperature of the smoothing treatment is not particularly limited, but is preferably 10 to 100°C, more preferably 10 to 50°C.

[0329] <Step 4>

[0330] The method for producing a conductive substrate may include step 3 of subjecting the conductive thin wires obtained in the above steps to a heat treatment. By carrying out this step, conductive thin wires having a more excellent conductivity can be obtained.

[0331] The heat treatment performed in step 3 may be the heat treatment performed in step C described above.

[0332] [use]

[0333] The conductive substrate of the present invention can be applied to various uses, such as touch panels (or touch panel sensors), semiconductor chips, various electrical wiring boards, FPC (Flexible Printed Circuits), COF (Chip on Film), TAB (Tape Automated Bonding), antennas, multilayer wiring boards, motherboards, etc. Among them, the conductive substrate of the present invention is preferably used for touch panels (electrostatic capacitive touch panels).

[0334] When the conductive substrate of the present invention is used for a touch panel, the conductive thin wires described above can effectively function as detection electrodes.

[0335] When the conductive substrate of the present invention is used for a touch panel, examples of display panels used in combination with the conductive substrate include liquid crystal panels and OLED (Organic Light Emitting Diode) panels, and a combination with an OLED panel is preferred.

[0336] In addition, the conductive substrate may have a conductive portion having a structure different from that of the conductive thin wire in addition to the conductive thin wire. The conductive portion may be electrically connected to the conductive thin wire to be conductive. As the conductive portion, for example, peripheral wiring having a function of applying a voltage to the conductive thin wire and alignment marks for adjusting the position of a component stacked with the conductive substrate may be cited.

[0337] As the use of the conductive substrate of the present invention other than the above, for example, an electromagnetic wave shielding member that blocks electromagnetic waves such as radio waves and microwaves (ultra-short waves) generated from electronic devices such as personal computers and workstations and prevents static electricity can be cited. In addition to being used for personal computer main bodies, such electromagnetic wave shielding members can also be used for electronic devices such as image capture equipment and electronic medical equipment.

[0338] The conductive substrate of the present invention can also be used for a transparent heating element.

[0339] The conductive substrate of the present invention can be used in the form of a laminate having the conductive substrate and other components such as an adhesive sheet and a release sheet during handling and transportation. The release sheet functions as a protective sheet to prevent scratches on the conductive substrate during transportation of the laminate.

[0340] Furthermore, the conductive substrate may be treated in the form of a composite having the conductive substrate, the adhesive sheet, and the protective layer in this order, for example.

[0341] The conductive substrate of the present invention has been described in detail, but the present invention is not limited to the above-described embodiment, and various improvements or changes can be made without departing from the gist of the present invention.

[0342] Example

[0343] Below, enumerate embodiment and further specifically describe the feature of the present invention.As long as the material, reagent, amount of substance and its ratio and operation etc. shown in the following embodiment do not depart from the gist of the present invention, then can be changed suitably.Therefore, the scope of the present invention is not limited to the following examples.

[0344] [Example 1]

[0345] (Preparation of Silver Halide Emulsion)

[0346] To the following solution 1 maintained at 30°C and pH 4.5, 90% of each of the following solutions 2 and 3 were added over 20 minutes while stirring the following solution 1, thereby forming 0.16 μm core particles. Next, the following solutions 4 and 5 were added over 8 minutes to the resulting solution, and the remaining 10% of the following solutions 2 and 3 were added over 2 minutes to grow the core particles to 0.10 μm. Furthermore, 0.15 g of potassium iodide was added to the resulting solution, and the solution was aged for 5 minutes, thereby completing the particle formation.

[0347] 1 fluid:

[0348]

[0349] 2 fluids:

[0350] 300ml water

[0351] Silver nitrate 150g

[0352] 3 fluids:

[0353]

[0354] 4 fluids:

[0355] Water 100ml

[0356] Silver nitrate 50g

[0357] 5. Liquid:

[0358]

[0359] Then, water washing was performed by flocculation method according to the conventional method. Specifically, the temperature of the solution obtained above was lowered to 35°C, and the pH was lowered using sulfuric acid (within the range of pH 3.6±0.2) until the silver halide precipitated. Then, about 3 liters of supernatant were removed from the obtained solution (first water washing). Then, after adding 3 liters of distilled water to the solution from which the supernatant was removed, sulfuric acid was added until the silver halide precipitated. Again, 3 liters of supernatant were removed from the obtained solution (second water washing). The same operation as the second water washing was repeated once again (third water washing), and the water washing and desalting process was completed. The emulsion after water washing and desalting was adjusted to pH 6.4 and pAg 7.5, and 2.5 g of gelatin, 10 mg of sodium benzenethiosulfonate, 3 mg of sodium benzenethiosulfinate, 15 mg of sodium thiosulfate and 10 mg of chloroauric acid were added, and chemical sensitization was implemented to obtain the best sensitivity at 55°C. Then, 100 mg of 1,3,3a,7-tetraazaindene as a stabilizer and 100 mg of PROXEL (trade name, manufactured by ICI Co., Ltd.) as a preservative were added to the obtained emulsion. The finally obtained emulsion was a silver chlorobromide cubic grain emulsion containing 0.08 mol % of silver iodide, 70 mol % of silver chloride and 30 mol % of silver bromide, and having an average particle size (spherical equivalent diameter) of 100 nm and a coefficient of variation of 9%.

[0360] (Preparation of Photosensitive Layer-Forming Composition)

[0361] To the above emulsion, 1,3,3a,7-tetraazaindene (1.2×10- 4 mol / mol Ag), hydroquinone (1.2×10- 2 mol / mol Ag), citric acid (3.0×10- 4 mol / mol Ag), 2,4-dichloro-6-hydroxy-1,3,5-triazine sodium salt (0.90 g / mol Ag) and a trace amount of a hardener were added to obtain a composition. Next, the pH of the composition was adjusted to 5.6 using citric acid.

[0362] A polymer latex containing a polymer represented by the following (P-1) (hereinafter also referred to as "polymer 1"), a dispersant composed of dialkylphenyl PEO (PEO is the abbreviation of polyethylene oxide) sulfate and water (the ratio of the mass of the dispersant to the mass of the polymer 1 (the mass of the dispersant / the mass of the polymer 1, the unit is g / g) is 0.02, and the solid content is 22% by mass) is added to the above-mentioned composition in such a manner that the ratio of the mass of the polymer 1 in the composition to the total mass of gelatin (the mass of the polymer 1 / the mass of the gelatin, the unit is g / g) is 0.25 / 1, thereby obtaining a composition containing the polymer latex. Here, in the composition containing the polymer latex, the ratio of the mass of gelatin to the mass of silver derived from the silver halide (the mass of the gelatin / the mass of the silver derived from the silver halide, the unit is g / g) is 0.11.

[0363] Furthermore, EPOXY RESIN DY 022 (trade name, manufactured by Nagase ChemteX Corporation) was added as a crosslinking agent. The amount of the crosslinking agent in the silver halide-containing photosensitive layer described later was set to 0.09 g / m 2 The amount of the crosslinking agent added was adjusted in the manner of . Surfactant 1 and surfactant 2 described below and sodium polystyrene sulfonate (molecular weight about 1 million) as a thickener were further added.

[0364] As described above, a photosensitive layer-forming composition was prepared.

[0365] In addition, polymer 1 was synthesized with reference to Japanese Patent Nos. 3305459 and 3754745.

[0366] [Chemical formula 5]

[0367] (P-1)

[0368] The above polymer latex was applied to a polyethylene terephthalate film ("roll-shaped long film manufactured by Fujifilm Corporation") having a thickness of 40 μm to form a primer layer having a thickness of 0.05 μm. This treatment was performed by roll-to-roll, and the following treatments (steps) were also performed by roll-to-roll in the same manner. In addition, the roll width at this time was 1 m and the length was 1000 m.

[0369] (Process E-1, process A-1, process F-1)

[0370] Next, a layer-forming composition not containing silver halide, the above-mentioned photosensitive layer-forming composition and a protective layer-forming composition described below are simultaneously applied as a multilayer on the undercoat layer to form a layer not containing silver halide, a photosensitive layer containing silver halide and a protective layer on the undercoat layer.

[0371] Here, the composition for forming a layer containing no silver halide is composed of the above-mentioned polymer 1, gelatin, a solid dispersion containing a dye described later, a surfactant 1, a surfactant 2, a surfactant 3, and an aqueous solution of sodium polystyrene sulfonate (molecular weight of about 1 million) as a thickener, the thickness of the layer containing no silver halide is 2.0 μm, the mixing mass ratio of the polymer 1 and gelatin in the layer containing no silver halide (polymer 1 / gelatin) is 2 / 1, and the content of the polymer 1 is 1.3 g / m 2 And, the content of dye is 0.08g / m 2 The contents of surfactant 1, surfactant 2, surfactant 3 and thickener are 0.02 g / m 2 , 0.02g / m 2 , 0.02g / m 2 , 0.04g / m 2 .

[0372] The thickness of the silver halide-containing photosensitive layer was 2.5 μm, the mixing mass ratio of polymer 1 to gelatin in the silver halide-containing photosensitive layer (polymer 1 / gelatin) was 0.25 / 1, and the content of polymer 1 was 0.19 g / m 2 In addition, the contents of surfactant 1, surfactant 2, and thickener were 0.04 g / m 2 , 0.01g / m 2 , 0.01g / m 2 .

[0373] The protective layer-forming composition comprises the polymer 1, gelatin, colloidal silica (average particle size of 12 nm: manufactured by Nissan Chemical Corporation, SNOWTEX C), surfactant 1, surfactant 2, surfactant 3, surfactant 4, sodium polystyrene sulfonate (molecular weight of about 1 million) as a thickener, and an aqueous solution of N,N'-bis(vinylsulfonylacetyl)ethylenediamineethylenebis(vinylsulfonylacetamide) as a gelatin crosslinking agent, the protective layer having a thickness of 0.15 μm, a mixing mass ratio of the polymer 1 to the gelatin in the protective layer (polymer 1 / gelatin) of 0.1 / 1, and a content of the polymer 1 of 0.015 g / m 2 In addition, the content of colloidal silica is 0.1 g / m 2The contents of surfactant 1, surfactant 2 (average molecular weight 1368), surfactant 3, surfactant 4, and thickener were 0.01 g / m 2 , 0.02g / m 2 , 0.02g / m 2 , 0.001g / m 2 , 0.01g / m 2 The content of the gelatin cross-linking agent was 3% by mass based on the total mass of gelatin in all the layers.

[0374] [Chemical formula 6]

[0375] dye

[0376]

[0377] [Chemical formula 7]

[0378] Surfactant 1

[0379]

[0380] [Chemical formula 8]

[0381] Surfactant 2

[0382]

[0383] [Chemical formula 9]

[0384] Surfactant 3

[0385]

[0386] [Chemical formula 10]

[0387] Surfactant 4

[0388]

[0389] (Process B-1)

[0390] The prepared photosensitive layer was exposed to light through a grid-shaped photomask using parallel light from a high-pressure mercury lamp as a light source. A pattern forming mask was used as the photomask to form a pattern such as Figure 2 The line width of a unit square grid of the grid shown is 1.2 μm, and the length L of one side of the grid (opening) is 600 μm.

[0391] After exposure, the obtained sample was developed with a developer described later, and then developed with a fixing solution (trade name: N3X-R for CN16X: manufactured by Fujifilm Corporation), rinsed with 25°C pure water, and then dried to obtain a sample A having a silver-containing layer containing metallic silver formed in a grid pattern. In sample A, a conductive grid pattern area of ​​21.0 cm×29.7 cm was formed.

[0392] (Composition of developer)

[0393] The developer contains the following compounds in 1 liter (L).

[0394]

[0395] The obtained sample A was immersed in warm water at 50° C. for 180 seconds, and then dehydrated by an air shower and naturally dried.

[0396] (Process C-1)

[0397] The sample A obtained in step B-1 was placed in a superheated steam treatment tank at 110°C and allowed to stand for 30 seconds to be subjected to superheated steam treatment. The steam flow rate at this time was 100 kg / h.

[0398] (Process D-1)

[0399] The sample A obtained in step C-1 was immersed in a proteolytic enzyme aqueous solution (40° C.) for 30 seconds. The sample A was taken out from the proteolytic enzyme aqueous solution, and was immersed in warm water (liquid temperature: 50° C.) for 120 seconds for washing. Then, it was dehydrated with an air shower and dried naturally.

[0400] The proteolytic enzyme aqueous solution used was prepared according to the following procedure.

[0401] Triethanolamine and sulfuric acid were added to an aqueous solution of a proteolytic enzyme (BIOPRASE 30L manufactured by Nagase ChemteX Corporation) (proteolytic enzyme concentration: 0.5 mass %) to adjust the pH to 8.5.

[0402] (Process G-1)

[0403] Sample A obtained in step D-1 was immersed in a 1 mass % glutaric acid aqueous solution (70° C.) for 2 minutes. Sample A was taken out from the glutaric acid aqueous solution and immersed in 30° C. water for 5 seconds and washed. Glutaric acid manufactured by FUJIFILM Wako Pure Chemical Corporation was used.

[0404] (Process 2-1)

[0405] The sample A obtained in step G-1 was immersed in a plating solution A (30° C.) having the following composition for 5 minutes. The sample A was taken out from the plating solution A, and was immersed in a 1 mass % citric acid buffer solution (pH=5, liquid temperature: 25° C.) for 30 seconds and washed. That is, neutralization washing was performed.

[0406] The composition of the plating solution A (total amount 1200 ml) is as follows. In addition, the pH of the plating solution A was 9.9, which was adjusted by adding a predetermined amount of potassium carbonate (manufactured by FUJIFILM Wako Pure Chemical Corporation). In addition, the following components used were all components manufactured by FUJIFILM Wako Pure Chemical Corporation. No change in line width was observed before and after the plating treatment.

[0407] (Composition of Plating Solution A)

[0408]

[0409] (Process 4-1)

[0410] The sample A obtained in step 2-1 was placed in a superheated steam treatment tank at 110°C and allowed to stand for 30 seconds to be subjected to superheated steam treatment. The steam flow rate at this time was 100 kg / h.

[0411] In the sample A obtained in step 4-1, the conductive thin wires formed a mesh pattern. The line width of the conductive thin wires was 1.8 μm, and the height of the conductive thin wires was 1.8 μm.

[0412] In addition, 100 samples B having a comb-shaped pattern for migration test formed on a substrate were prepared in the same procedure as above except that the photomask used in the above (step B-1) was changed. The migration test pattern was a pattern formed in accordance with IPC-TM650 or SM840, with a line width of 10 μm, a space width of 10 μm, a line length of 30 cm, and a number of lines of 17 / 18.

[0413] [Examples 2 to 3, Comparative Examples 1 to 4]

[0414] As Examples 2 to 3 and Comparative Examples 1 to 4, instead of the plating solution A used in the above step 2-1, plating solutions in which the addition amounts of the components were adjusted so that the contents of potassium iodide and methylhydroquinone as a reducing agent were the contents described in Table 1 described later were used, and sample A having a grid pattern formed by conductive fine wires and sample B having a comb-shaped pattern formed by conductive fine wires were respectively prepared according to the procedure described in Example 1. The components of the immersion solution used were all components manufactured by FUJIFILM Wako Pure Chemical Corporation.

[0415] [Determination of ratio I / Ag]

[0416] The ratio I / Ag on the surface of the conductive thin wires was measured for the conductive substrates obtained in each of the Examples and Comparative Examples according to the method based on the above-mentioned fluorescent X-ray analysis method.

[0417] The measurement results of the ratio I / Ag are shown in Table 1 described later.

[0418] [evaluate]

[0419] Hereinafter, the evaluation method of the conductivity and the migration suppression performance which are evaluation items of the conductive substrate will be described.

[0420] <Conductivity test>

[0421] The line resistance value of the conductive mesh pattern region was measured for the obtained conductive substrate sample A. The line resistance value is a value obtained by dividing the resistance value measured by the four-probe method by the distance between the measurement terminals.

[0422] The method for measuring the line resistance value is specifically shown. First, after disconnecting both ends of any one of the conductive thin wires constituting the grid pattern possessed by sample A and separating it from the grid pattern, four (A, B, C, D) microprobes (tungsten probes (diameter 0.5 μm) manufactured by Micro Support Co., Ltd.) are brought into contact with the separated conductive thin wires, and a source meter (source meter manufactured by KEITHLEY, 2400 general source meter) is used to apply a constant current I to the outermost probes A and D in such a way that the voltage V between the internal probes B and C set at an interval of 250 μm becomes 5 mV, and the resistance value Ri=V / I is measured. The obtained resistance value Ri is divided by the distance between the probes B and C to obtain the measured value, and the arithmetic mean of the measured values ​​at any 10 locations is taken as the line resistance value. Based on the obtained line resistance value, the conductivity of each sample A was evaluated according to the following standards. As an evaluation of conductivity, among the following 1 to 5, 3 or more is preferred, 4 or more is more preferred, and 5 is further preferred.

[0423] 5: Wire resistance value is less than 50Ω / mm.

[0424] 4: The line resistance value is 50Ω / mm or more and less than 60Ω / mm.

[0425] 3: The line resistance value is 60Ω / mm or more and less than 80Ω / mm.

[0426] 2: The line resistance value is 80Ω / mm or more and less than 100Ω / mm.

[0427] 1: The wire resistance value is 100Ω / mm or more.

[0428] <Migration test>

[0429] Sample B was left standing in a humid and hot environment of 60°C and 90%RH, wires were connected to both ends of Sample B, and a DC current of 5V was continuously applied from one side. Sample B was taken out from the 60°C and 90%RH environment after a predetermined time, and the insulation resistance of Sample B was measured using R8340A manufactured by ADVANTEST CORPORATION.

[0430] Based on the time elapsed from the start of the test and the measured value of the insulation resistance of the sample B, the migration inhibition performance of the sample B was evaluated according to the following criteria.

[0431] (Migration test evaluation criteria)

[0432] "A": When more than 500 hours have passed since the start of the test, the insulation resistance value is 10 10 Ω or more.

[0433] "B": When more than 240 hours have passed since the start of the test, the insulation resistance value is 10 10 Ω or more, but the insulation resistance value decreases to less than 10 before 500 hours 10 Ω.

[0434] "C": From the start of the test to 240 hours later, the insulation resistance value drops to less than 10 10 Ω.

[0435] In the table, "C KI The column "[mmol / L]" indicates the content of potassium iodide in the plating solution (unit: mmol / L). R The "[mmol / L]" column indicates the content of the reducing agent in the plating solution (unit: mmol / L).

[0436] The "Ratio C" column of "Electroplating Solution" indicates that when the content of potassium iodide in the plating solution is set to C KImmol / L, the content of the reducing agent in the plating solution is set as C R mmol / L, the passing ratio is C=C KI / C R ×1000.

[0437] The “Line width [μm]” column of “Conductive thin wire” indicates the line width (unit: μm) of the conductive thin wire, and the “Height [μm]” column indicates the height (unit: μm) of the conductive thin wire.

[0438] The column “I / Ag” of “Conductive thin wire” indicates the ratio of the amount of iodine atoms to the amount of silver atoms on the surface of the conductive thin wire measured by fluorescent X-ray analysis.

[0439] [Table 1]

[0440]

[0441] As shown in the above Table 1, the conductive substrate of the present invention exhibits the intended effects.

[0442] Explanation of symbols

[0443] 10-conductive substrate, 12-substrate, 12a-surface, 14, 14B-conductive thin wires, 18-opening, Ac-vertical cross section, DL, DW-directions, L-length.

Claims

1. A conductive substrate comprising a substrate and conductive fine wires disposed on the substrate and containing silver, When the surface of the conductive thin wire is measured by fluorescent X-ray analysis, the ratio of the amount of iodine atoms to the amount of silver atoms detected is 0.035 to 0.

100.

2. The conductive substrate according to claim 1, wherein The conductive thin wire has a line width of 0.1 μm or more and less than 5.0 μm.

3. The conductive substrate according to claim 1, wherein In a vertical cross section of the conductive thin wire in a direction perpendicular to the direction in which the conductive thin wire extends, a ratio of a height of the conductive thin wire to a line width of the conductive thin wire is greater than or equal to 0.6 and less than 1.

5.

4. The conductive substrate according to claim 1, wherein The conductive fine wire has a line width of 0.1 μm or more and less than 5.0 μm, In a vertical cross section of the conductive thin wire in a direction perpendicular to the direction in which the conductive thin wire extends, a ratio of a height of the conductive thin wire to a line width of the conductive thin wire is greater than or equal to 0.6 and less than 1.

5.

5. The conductive substrate according to any one of claims 1 to 3, wherein: The silver contained in the conductive thin wire is in a particle form.

6. The conductive substrate according to any one of claims 1 to 3, wherein: The substrate is a flexible substrate.

7. The conductive substrate according to claim 6, wherein The material constituting the flexible substrate is at least one selected from the group consisting of polyethylene terephthalate, cycloolefin polymer, cycloolefin copolymer, and polycarbonate.

8. A method for manufacturing a conductive substrate, the conductive substrate comprising a substrate and conductive fine wires disposed on the substrate and containing silver, the method for manufacturing the conductive substrate sequentially comprising: Step 1, forming a thin line-shaped metal-containing layer on the substrate; and Step 2, performing electroless plating on the metal-containing layer to form the conductive fine wires, The plating solution used in the electroless plating treatment comprises potassium iodide and a reducing agent. The content of the reducing agent in the plating treatment solution is 60 mmol / L or less, The contents of the potassium iodide and the reducing agent in the plating solution are respectively set to C KI mmol / L and C R mmol / L, satisfying C KI / C R ×1000≤0.

7.

9. The method for producing a conductive substrate according to claim 8, wherein: The electroless plating treatment is electroless silver plating treatment.

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