Base material including conductive pattern, electronic device, electromagnetic shielding film and planar heating element

Abstract

To provide a base material having a conductive pattern having good conductivity.SOLUTION: A base material including a conductive pattern includes a base material, and the conductive pattern which is positioned on at least one surface side of the base material, and includes a plurality of conductive particles. In a part with maximum thickness of the conductive pattern, in a cross section of the conductive pattern in the base material, a square region S0 of 8 μm square is set as close as possible to the base material, and a square region S1 of 8 μm square is set as far as possible from the base material. An area ratio of a part where the conductive particles exist in the square region S0 is represented by ε0, and an area ratio of a part where the conductive particles exist in the square region S1 is represented by ε1. At this time, ε1 is 65% or more, and ε0<ε1 is satisfied.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a substrate provided with a conductive pattern, an electronic device, an electromagnetic wave shielding film, and a sheet heating element. [Background technology]

[0002] Formation of a conductive pattern, such as a circuit pattern, on a substrate using a conductive composition containing conductive particles has been investigated. Conductive compositions containing conductive particles are sometimes called conductive pastes, conductive inks, etc.

[0003] Patent Document 1 discloses a wiring board comprising a wiring layer containing a conductor composition mainly composed of a low-resistance metal formed on the surface of an insulating layer containing at least an organic resin, wherein the wiring layer comprises, from the insulating layer side, a first layer consisting of the conductor composition and the organic resin in the insulating layer, and a second layer consisting of the conductor composition, and the thickness of the first layer is at least 0.3 times the average particle size of the low-resistance metal particles and is thinner than the second layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 3597952 Summary of the Invention [Problem to be solved by the invention]

[0005] The conductive pattern formation technology using conductive compositions containing conductive particles is thought to be applicable to printed electronics, which has been actively developed in recent years. Printed electronics is a technology that uses printing technology to form electronic circuits, sensors, elements, etc. on substrates such as films.

[0006] An object of the present invention is to provide a substrate having a conductive pattern with good electrical conductivity. [Means for solving the problem]

[0007] The present inventors have completed the invention provided below and solved the above problems.

[0008] 1. A substrate with a conductive pattern, comprising: a substrate; and a conductive pattern including a plurality of conductive particles provided on one surface side of the substrate, In a cross section of the conductive pattern, in a portion where the thickness of the conductive pattern is greatest, a square region S0 of 8 μm square is set as close as possible to the substrate, and a square region S1 of 8 μm square is set as far as possible from the substrate; When the area ratio of the portion where the conductive particles exist in the square region S0 is ε0 and the area ratio of the portion where the conductive particles exist in the square region S1 is ε1, A substrate provided with a conductive pattern, wherein ε1 is 65% or more and ε0<ε1. 2. A substrate provided with the conductive pattern according to 1. A substrate provided with a conductive pattern, wherein the ε0 is less than 45%. 3. A substrate provided with the conductive pattern according to 1. A substrate provided with a conductive pattern, wherein the ε0 is greater than 60%. 4. A substrate provided with the conductive pattern according to any one of 1. to 3., A substrate provided with a conductive pattern, wherein the value of ε1 / ε0 is 1.2 to 3.0. 5. A substrate provided with the conductive pattern according to any one of 1. to 4., Within the square region S0, a resin component has permeated at least a part of a portion where no conductive particles are present, A substrate having a conductive pattern, wherein when a cross section of the conductive pattern is observed with an electron microscope, two layers are observed: a layer infiltrated with the resin component and a layer not infiltrated with the resin component. 6. 5. A substrate provided with the conductive pattern according to claim 5, A substrate provided with a conductive pattern, wherein the maximum thickness of the layer infiltrated with the resin component is 5 to 50% of the maximum thickness of the conductive pattern. 7. A substrate provided with the conductive pattern according to 5. or 6., The substrate includes at least a substrate layer and a cured resin layer, a portion of the conductive pattern is in contact with the cured resin layer; The resin component is formed by penetration and hardening of a curable resin material that forms the cured resin layer. 8. A substrate provided with the conductive pattern according to any one of 1. to 7., A substrate having a conductive pattern, wherein the resin component does not substantially contain an inorganic filler. 9. A substrate provided with the conductive pattern according to any one of 1. to 8., The particle diameter D at which the cumulative frequency reaches 50% in a volume-based cumulative particle diameter distribution curve obtained when the particle diameter of the conductive particles is measured by a laser diffraction scattering method. 50 A substrate having a conductive pattern, wherein the thickness is 0.5 to 100 μm. 10. A substrate provided with the conductive pattern according to any one of 1. to 9., The substrate is flexible and has a conductive pattern. 11. A substrate provided with the conductive pattern according to any one of 1. to 10., A method for manufacturing a substrate having a conductive pattern, wherein the substrate includes at least one selected from the group consisting of polyester, polyolefin, polycarbonate, polyimide, and paper. 12. An electronic device comprising a substrate having the conductive pattern according to any one of 1. to 11. 13. 12. The electronic device according to claim 12, An electronic device that is an RF tag. 14. An electromagnetic wave shielding film comprising a substrate having the conductive pattern according to any one of 1. to 11. 15. A sheet heating element comprising a substrate having the conductive pattern according to any one of 1. to 11. 16. A substrate with a conductive pattern, comprising: a substrate; and a conductive pattern including a plurality of conductive particles provided on one surface side of the substrate, In a cross section of the conductive pattern, in a portion where the thickness of the conductive pattern is greatest, a square region S0' of 5 μm square is set as close as possible to the substrate, and a square region S1' of 5 μm square is set as far as possible from the substrate; When the area ratio of the portion where the conductive particles exist in the square region S0′ is ε0′ and the area ratio of the portion where the conductive particles exist in the square region S1′ is ε1′, A substrate having a conductive pattern, wherein ε1' is 65% or more and ε0'<ε1'. [Effects of the Invention]

[0009] The conductive pattern in the substrate provided with the conductive pattern of the present invention has good conductivity. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram schematically illustrating a cross section of a substrate provided with a conductive pattern according to an embodiment of the present invention. [Figure 2] 1A to 1C are diagrams illustrating an example of a method for manufacturing a conductive pattern according to an embodiment of the present invention. [Figure 3] 1A to 1C are diagrams illustrating an example of a method for manufacturing a conductive pattern according to an embodiment of the present invention. [Figure 4] 10A to 10C are diagrams for explaining another example of the method for manufacturing a conductive pattern according to the present embodiment. [Figure 5] 10A to 10C are diagrams for explaining another example of the method for manufacturing a conductive pattern according to the present embodiment. [Figure 6]FIG. 2 is a diagram showing the shape of a conductive pattern (antenna pattern) produced in an example. [Figure 7] FIG. 1 shows a cross-sectional image of a substrate provided with a conductive pattern obtained in Example I-1 and the calculation results of ε0, ε1, ε0', and ε1'. [Figure 8] FIG. 10 is a diagram showing a cross-sectional image of a substrate provided with a conductive pattern obtained in Example II-1 and the calculation results of ε0, ε1, ε0', and ε1'. [Figure 9] FIG. 10 is a diagram showing a cross-sectional image of a substrate provided with a conductive pattern obtained in Example III-1 and the calculation results of ε0, ε1, ε0', and ε1'. [Figure 10] FIG. 4 is a diagram showing a cross-sectional image of a substrate provided with a conductive pattern obtained in Example IV-1 and the calculation results of ε0, ε1, ε0', and ε1'. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all the drawings, similar components are denoted by similar reference numerals and descriptions thereof will be omitted where appropriate. To avoid complexity, (i) when there are multiple identical components in the same drawing, only one of them is given a symbol, and not all of them, or (ii) particularly in Figure 2 and subsequent figures, components similar to those in Figure 1 are not given a symbol again. All drawings are for illustrative purposes only, and the shapes and dimensional ratios of the components in the drawings do not necessarily correspond to the actual products.

[0012] In this specification, unless otherwise specified, the expression "X to Y" in the description of a numerical range means at least X and at most Y. For example, "1 to 5% by mass" means "at least 1% by mass and at most 5% by mass."

[0013] In this specification, the term "(meth)acrylic" represents a concept that encompasses both acrylic and methacrylic. The same applies to similar terms such as "(meth)acrylate." In this specification, the term "electronic device" is used to encompass elements, devices, final products, etc. to which electronic engineering technology is applied, such as semiconductor chips, semiconductor elements, printed wiring boards, electric circuit display devices, information and communication terminals, light-emitting diodes, physical batteries, and chemical batteries.

[0014] <Substrate with conductive pattern> The substrate with a conductive pattern of this embodiment includes a substrate and a conductive pattern including a plurality of conductive particles provided on one surface of the substrate. Fig. 1 is a diagram showing a cross section of a substrate provided with a conductive pattern according to this embodiment. The thick line in Fig. 1 represents the cross section of the conductive pattern. In other words, the thick line and the area inside it constitute the "cross section" of the conductive pattern. The cross section is preferably taken in a direction perpendicular to the direction in which the conductive pattern extends in a straight line portion of the conductive pattern.

[0015] In the cross section of this conductive pattern, at the part where the conductive pattern is at its thickest, a square region S0 of 8 μm square is set as close as possible to the substrate, and a square region S1 of 8 μm square is set as far away as possible from the substrate. Both square regions S0 and S1 exist entirely within the cross section of the conductive pattern, and no part of the square extends outside the conductive pattern. The square region S0 being "as close as possible to the substrate" means that the square region S0 is set so that at least a portion of the periphery of an 8 μm square is in contact (but does not intersect or extend beyond) with the portion of the conductive pattern in Figure 1 that is in contact with the substrate and has the greatest thickness, as shown by the outline (thick line) of the cross section of the conductive pattern. Similarly, the square region S1 being located "as far away from the substrate as possible" means that the square region S0 is set so that at least a portion of the periphery of an 8 μm square is in contact with (but does not intersect with or extend beyond) the portion of the cross-sectional outline (thick line) of the conductive pattern in Figure 1 that is not in contact with the substrate and is near the part of the conductive pattern where the thickness is greatest.

[0016] The area ratio of the portion of square region S0 where conductive particles exist is defined as ε0. The area ratio of the portion of square region S1 where conductive particles exist is defined as ε1. ε0 and ε1 can be determined by using, for example, image processing software to calculate the areas of the portions of each region that appear bright due to the presence of conductive particles and the areas of the portions that appear dark due to the absence of conductive particles. In this embodiment, ε1 is 65% or more, and ε0<ε1.

[0017] When forming a conductive pattern using conductive particles, it is considered important to densify the conductive particles as much as possible by applying heat or pressure to the conductive particles in order to increase the conductivity of the conductive pattern, but this may require, for example, a large amount of cost.

[0018] Through various investigations, the present inventors have found that, in forming a conductive pattern using conductive particles, (i) good conductivity can be obtained if a portion of the conductive pattern is sufficiently densified, and (ii) other portions of the conductive pattern do not need to be so densified. The substrate provided with the conductive pattern of this embodiment quantitatively expresses item (i) as ε1 being 65% or more, and item (ii) as ε0 < ε1.

[0019] From the viewpoint of particularly improving conductivity, it may be ideal for the entire conductive pattern to be highly densified. However, this is not necessarily the case, and good conductivity can be obtained even if only a portion of the conductive pattern is highly densified. This is a surprising result. While densifying the entire conductive pattern tends to increase costs, the substrate provided with the conductive pattern of this embodiment is thought to be able to be manufactured at a relatively low cost.

[0020] The substrate having the conductive pattern of this embodiment can be manufactured by using appropriate raw materials and employing appropriate manufacturing methods and manufacturing conditions. If appropriate raw materials are not used or appropriate manufacturing methods and manufacturing conditions are not employed, it may not be possible to manufacture the substrate having the conductive pattern of this embodiment. Specific aspects of the manufacturing method and manufacturing conditions will be explained later, but briefly, when forming a conductive pattern, by appropriately penetrating a curable resin component into the gaps between the conductive particles, areas where the conductive particles are densely present and areas where they are sparsely present are created in the conductive pattern, and a conductive pattern that satisfies the above-mentioned ε0 and ε1 specifications is formed. Incidentally, the penetration of the curable resin component can also contribute to suppressing unintended peeling of the conductive pattern.

[0021] The substrate provided with the conductive pattern of this embodiment will now be described.

[0022] (Conductive particles) As described above, the conductive pattern includes a plurality of conductive particles, and preferably, at least a portion of the plurality of conductive particles in the conductive pattern are sintered and connected to one another.

[0023] The conductive particles preferably contain at least one element selected from the group consisting of silver and copper, from the viewpoints of availability and good conductivity. Specifically, the conductive particles preferably include at least one selected from the group consisting of particles primarily composed of silver and particles primarily composed of copper. Here, the expression "primarily composed of silver" means that the ratio of silver element to all constituent elements in the particles is preferably 50 mol% or more, more preferably 75 mol% or more, even more preferably 90 mol% or more, and particularly preferably 95 mol% or more. Similarly, the expression "primarily composed of copper" means that the ratio of copper element to all constituent elements in the particles is preferably 50 mol% or more, more preferably 75 mol% or more, even more preferably 90 mol% or more, and particularly preferably 95 mol% or more.

[0024] As long as the desired conductivity is obtained, the conductive particles may or may not contain elements other than silver and copper, such as gold, aluminum, platinum, palladium, iridium, tungsten, nickel, tantalum, lead, tin, zinc, etc. However, from a cost perspective, it is preferable that the conductive particles contain no elements other than silver and copper, or contain only small amounts of such elements. By performing the pressing step in the method for producing a substrate with a conductive pattern described below, a conductive pattern with good conductivity can be produced even if the conductive particles contain no elements other than silver and copper, or contain only small amounts of such elements. Specifically, the conductive particles may or may not contain a low-melting-point metal such as tin, lead, or indium. Specifically, the proportion of the low-melting-point metal with a melting point of 400°C or less in the plurality of conductive particles is preferably 0 to 5% by mass, more preferably 0 to 3% by mass, and even more preferably 0 to 1% by mass.

[0025] The conductive particles may contain two or more elements. For example, conductive particles in which the surfaces of copper particles are silver-plated (silver-coated copper particles) are preferably used in this embodiment. Silver-coated copper particles are particles whose main component is copper, and the surfaces of the copper particles are plated with silver in an amount of up to 35 mass% based on the total mass of the particles, for example.

[0026] The particle diameter D at which the cumulative frequency reaches 50% in the volume-based cumulative particle diameter distribution curve obtained when the particle diameter of conductive particles is measured by the laser diffraction scattering method. 50 is preferably 0.5 to 100 μm, more preferably 0.6 to 50 μm, even more preferably 0.7 to 30 μm, and particularly preferably 0.7 to 20 μm. D 50 By making the ρ appropriately large, the number of grain boundaries between conductive particles per unit volume can be reduced, which is thought to lead to a smaller specific resistance of the resulting conductive pattern. D 50 It is believed that by not making the size too large, the "gaps" between the conductive particles are reduced, which leads to a smaller specific resistance of the resulting conductive pattern.

[0027] Conductive particles can be purchased from, for example, DOWA Electronics Co., Ltd., Fukuda Metal Foil and Powder Co., Ltd. Two or more different conductive particles may be used in combination to adjust or optimize particle size distribution or for other purposes.

[0028] (ε0, ε1 and ε1 / ε0) As described above, in this embodiment, ε1 is 65% or more, and ε0<ε1. From the viewpoint of good conductivity of the conductive pattern and ease of manufacturing the conductive pattern, ε1 is preferably 65 to 99%, more preferably 65 to 97%, and even more preferably 70 to 96%. From the viewpoints of ease of manufacturing the conductive pattern and suppressing peeling of the conductive pattern, which will be described later, ε0 is preferably 20 to 70%, more preferably 25 to 70%, and even more preferably 30 to 68%. From another viewpoint, ε0 may be less than 45%, specifically 20 to 44%, or may be more than 60%, specifically 61 to 99%.

[0029] From the viewpoint of the manufacturability of the conductive pattern and the manufacturing costs of the conductive pattern, the value of ε1 / ε0 is preferably 1.2 to 3.0, and more preferably 1.3 to 2.7.

[0030] (Penetration of resin components) It is preferable that the resin component penetrates into part or all of the square region S0 where no conductive particles are present, which is thought to contribute to improving the adhesion of the conductive pattern to the substrate.

[0031] When the cross section of a conductive pattern is observed with an electron microscope, two layers can sometimes be observed: one that is permeated with a resin component and one that is not permeated with a resin component. Cross-sectional images of conductive patterns obtained in Examples described below are shown in Figures 7 to 10, and in these images, it can be clearly seen that the conductive pattern is divided into two layers: one that is permeated with the resin component of the conductive pattern and one that is not permeated with a resin component.

[0032] The maximum thickness of the layer infiltrated with the resin component is preferably (tentatively) 5 to 50%, more preferably 10 to 50%, and even more preferably 10 to 40% of the maximum thickness of the conductive pattern. Conversely, the maximum thickness of the layer not infiltrated with the resin component is preferably 50 to 95%, more preferably 50 to 90%, and even more preferably 60 to 90% of the maximum thickness of the conductive pattern.

[0033] From the viewpoint of improving the conductivity of the conductive pattern as a whole, it is preferable that the resin component is substantially free of inorganic filler. "Substantially free of inorganic filler" means that the content of inorganic filler in the resin component is typically 0 to 3 mass %, specifically 0 to 1 mass %.

[0034] (Layer composition) 1, the substrate may include a substrate layer and a cured resin layer. The substrate may have a two-layer structure of the substrate layer and the cured resin layer. A portion of the conductive pattern may be in contact with the cured resin layer.

[0035] The resin component that has infiltrated into the square region S0 is preferably the curable resin material that has infiltrated and hardened to form the cured resin layer. It is believed that the curable resin material forming the cured resin layer penetrates into a part of the conductive pattern, thereby producing a so-called anchor effect, which further prevents the conductive pattern from unintentionally peeling off.

[0036] Examples of the curable resin material include various thermosetting or photocurable resin materials, such as epoxy resin-containing materials, polymerizable (meth)acrylate-containing materials, urethane-based materials, urethane (meth)acrylate-containing materials, and silicone-based materials. Commercially available curable resin materials can also be used. For example, the adhesive layer 2 can be formed using various thermosetting or photocurable resin materials known or commercially available as hard coating agents. Also, commercially available OCA (Optically Clear Adhesive) films, die attach films, and the like can be used. Additionally, various thermosetting or photocurable resin materials known or commercially available as primers can also be used. In terms of chemical composition, the curable resin material is preferably a (meth)acrylic resin-based curable material or an epoxy resin-based curable material.

[0037] The substrate is preferably flexible. By employing a flexible substrate, a flexible printed circuit (FPC) can be manufactured. By using a flexible substrate, it becomes easier to apply pressure using a "roll" in the manufacturing method described below. This is preferable from the viewpoint of mass production. Just to be clear, the substrate may be a rigid substrate that does not have flexibility.

[0038] The substrate preferably contains at least one selected from the group consisting of polyester, polyolefin, polycarbonate, polyimide, and paper. More specifically, the substrate layer of the substrate preferably contains at least one selected from the group consisting of polyester, polyolefin, polycarbonate, polyimide, and paper.

[0039] The thickness of the substrate is not particularly limited and can be appropriately set depending on the final use (electronic device, RF tag, electromagnetic wave shielding film, planar heating element, etc.) described below and various other circumstances. The thickness of the substrate is typically 10 to 250 μm, preferably 30 to 100 μm. However, from the viewpoint of suppressing the occurrence of curling, it is preferable that the substrate is somewhat thick. Specifically, the thickness of the substrate is preferably 100 to 250 μm, more preferably 100 to 150 μm. When the substrate has a two-layer structure consisting of a substrate layer and a cured resin layer, it is preferable that the substrate layer accounts for more than 50% of the thickness of the substrate. The thicknesses of the substrate layer and the cured resin layer can be, for example, the thickness of each layer at the thickest part of the conductive pattern.

[0040] <Substrate with Conductive Pattern: Another Embodiment> In Figure 1 etc., square regions S0 and S1 of 8 μm square are defined in the cross section of the conductive pattern, and the area ratio of the portion where conductive particles exist within these regions is discussed. However, it is natural to consider regions that are not 8 μm square and consider the area ratio of the portion where conductive particles exist within those regions.

[0041] For example, consider a cross section of a substrate having a conductive pattern, the cross section being formed on one surface of the substrate and including a conductive pattern containing a plurality of conductive particles. The cross section is preferably taken in a direction perpendicular to the direction in which the conductive pattern extends in a linear portion of the conductive pattern. In the cross section of this conductive pattern, at the part where the conductive pattern is at its thickest, a square region S0' of 5 μm square is set as close as possible to the substrate, and a square region S1' of 5 μm square is set as far as possible from the substrate. The specific method for setting these square regions is the same as the square regions S0 and S1 described above in the section <Substrate with conductive pattern>, except that the size is 5 μm square instead of 8 μm square.

[0042] The area ratio of the portion of square region S0' where conductive particles exist is defined as ε0'. The area ratio of the portion of square region S1' where conductive particles exist is defined as ε1'. ε0' and ε1' can be determined by using, for example, image processing software to calculate the areas of the portions of each region that appear bright due to the presence of conductive particles and the areas that appear dark due to the absence of conductive particles. In this case, ε1' is preferably 65% ​​or more, and ε0'<ε1'.

[0043] From the viewpoint of good conductivity of the conductive pattern and ease of manufacturing the conductive pattern, ε1' is preferably 45 to 90%, and more preferably 50 to 85%. From the viewpoints of ease of manufacturing the conductive pattern and suppressing peeling of the conductive pattern, ε0' is preferably 25 to 90%, more preferably 30 to 85%. From another viewpoint, ε0' may be less than 45%, specifically 20 to 44%, or may be more than 60%, specifically 61 to 99%.

[0044] From the viewpoint of the manufacturability of the conductive pattern and the manufacturing costs of the conductive pattern, the value of ε1 / ε0 is preferably 1.1 to 3.0, and more preferably 1.1 to 2.5.

[0045] In another embodiment described here, the specific aspects of the conductive particles, the penetration of the resin component into a portion of the conductive pattern (e.g., region S0'), the layer structure, etc. can be the same as those described in the above <Substrate with a Conductive Pattern>. That is, the specific aspects of the other embodiment described here can be the same as those described in the above <Substrate with a Conductive Pattern>, except that when considering the area ratio of the portion where the conductive particles are present, a 5 μm square region is set instead of an 8 μm square region.

[0046] <Method of manufacturing a substrate provided with a conductive pattern> As briefly mentioned above, a substrate having the above-described conductive pattern can be manufactured by using an appropriate material and employing an appropriate manufacturing method and manufacturing conditions. If the manufacturing method or manufacturing conditions are inappropriate, it may not be possible to form a conductive pattern having the above-described specific cross-sectional shape. Hereinafter, preferred manufacturing methods (Examples 1 and 2) for manufacturing a substrate provided with the above-described conductive pattern will be described.

[0047] [Example 1] A preferred method for producing a substrate having a conductive pattern of this embodiment is to a transfer step in which a temporary pattern formed on the surface of an easily peelable substrate using a conductive composition containing conductive particles is brought into contact with an adhesive layer formed on the surface of a substrate different from the easily peelable substrate, thereby obtaining a transfer pattern in which the temporary pattern is transferred to the surface of the adhesive layer; a pressing step of applying at least pressure to the transfer pattern to obtain a conductive pattern; Includes.

[0048] The manufacturing method will be described in more detail below with reference to FIGS.

[0049] (Formation of temporary patterns on the surface of an easily peelable substrate: Figure 2P1, Figure 2P2) First, a temporary pattern is formed on the surface of an easily peelable substrate using a conductive composition containing conductive particles. Specifically, first, as shown in Fig. 2P1, pattern 3 is formed from a conductive composition containing conductive particles, typically in the form of a paste containing a solvent, on the surface of easily peelable substrate 5. Thereafter, by volatilizing the solvent in pattern 3, a temporary pattern (pattern 3B) can be obtained on easily peelable substrate 5, as shown in Fig. 2P2.

[0050] The method for forming the pattern 3 is not particularly limited. Various coating and printing techniques can be applied. The pattern 3 may be provided on the entire surface of the easily peelable substrate 5, or on only a portion of the surface of the easily peelable substrate 5. In the former case, the pattern 3 can be formed by coating using a device such as a blade coater, air knife coater, doctor coater, roll coater, bar coater (rod coater), or curtain coater. In the latter case, the pattern 3 can be formed by various printing methods, such as screen printing, gravure printing, letterpress printing, lithographic printing (offset printing), inkjet printing, and transfer printing. By appropriately designing the "pattern" during printing, it is possible to produce a substrate having a pattern structure, such as a conductive film (circuit pattern) that can function as a circuit or a mesh pattern with electromagnetic wave shielding properties. When the pattern 3 is provided on only a portion of the surface of the easily peelable substrate 5, it is preferable that the printing "pattern" be appropriately designed depending on the intended use of the substrate having the final conductive pattern. In order to prevent the pattern 3 from being formed in any location other than the desired location on the easily peelable substrate 5, for example, a film with holes cut out therein may be placed on the easily peelable substrate 5, a conductive composition may be applied or printed on top of it, and then the film may be removed.

[0051] The easily peelable substrate 5 is not particularly limited as long as it can be easily peeled in the peeling step described below, that is, as long as the temporary pattern (pattern 3B) can be easily separated. Specific examples of the easily peelable substrate 5 include resin films. More specifically, examples include resin films with a silicone resin applied to the surface and resin films with a silicone resin kneaded into them. The main material of these resin films is not particularly limited, but in consideration of strength and cost, polyester-based materials are preferred, and polyethylene terephthalate is more preferred. In addition, various films commercially available under names such as "release film" and "peeling film" can also be used as the easily peelable substrate 5. Furthermore, release paper can also be used as the easily releasable substrate 5. Release paper typically refers to laminated paper in which a thin film-like resin is laminated on paper to give it easy releasability. Release paper is sometimes expressed as release paper. As for the release paper, various types of commercially available release paper can be used as appropriate.

[0052] The easily peelable substrate 5 may be in the form of a film or sheet as shown in Figure 2P1 or Figure 2P2, or may be in the form of a roll, for example. For example, a roll whose surface is made of metal or resin, on which a temporary pattern can be formed and from which the temporary pattern can be easily separated, may be used as the easily peelable substrate 5. Use of a roll-shaped easily peelable substrate 5 can be expected to improve the productivity of substrates having conductive patterns. The easily peelable substrate 5 may be disposable or may be reused.

[0053] The surface of the easily peelable substrate 5 is usually flat. The surface of the easily peelable substrate 5 usually does not have any recesses or protrusions. The easily peelable substrate 5 is usually not an intaglio or relief printing plate.

[0054] When the easily peelable substrate 5 is in the form of a film or sheet, its thickness is not particularly limited, but taking into consideration the handleability and transfer accuracy of the easily peelable substrate 5, it is preferably 10 to 250 μm, more preferably 10 to 100 μm.

[0055] The heating conditions for volatilizing the solvent in pattern 3 to obtain a temporary pattern (pattern 3B) can be, for example, 50 to 150°C for 1 to 60 minutes. However, it is preferable to set the temperature at a level that does not damage the easily peelable substrate 5. Heating can be performed, for example, by applying hot air to pattern 3, or by placing the easily peelable substrate 5 and pattern 3 on a hot plate. As a further example, heating by light is also possible. Specific examples include heating using a far-infrared heating furnace (IR oven) or Adphos NIR (ultra-near infrared), heating with a high-brightness LED, and laser heating.

[0056] The height of the provisional pattern (pattern 3B) is preferably 0.5 to 100 μm, more preferably 5 to 60 μm, and even more preferably 10 to 40 μm. When this height is 0.5 μm or more, the conductivity of the final conductive pattern can be improved. On the other hand, when this height is 100 μm or less, the entire substrate provided with the final conductive pattern can be made thinner. This is preferable, for example, from the viewpoint of miniaturization and weight reduction of electronic devices.

[0057] It is preferable that the conductive particles in the temporary pattern (pattern 3B) are not substantially sintered, although the conductive particles are usually sintered in the pressing step described below. Furthermore, it is preferable that the temporary pattern (pattern 3B) is substantially uncured. Specifically, even if the conductive composition contains a curable resin, a crosslinking agent, or the like, it is preferable that the curable resin or crosslinking agent in the temporary pattern (pattern 3B) is substantially unreacted before the transfer step.

[0058] The conductive composition for forming the temporary pattern (pattern 3B) is preferably in a paste state at room temperature for ease of pattern formation. From the viewpoint of further increasing the conductivity of the finally obtained conductive pattern, the amount of the resin component in the conductive composition is preferably 15 parts by mass or less, i.e., 0 to 15 parts by mass, more preferably 0 to 10 parts by mass, and even more preferably 0 to 5 parts by mass, per 100 parts by mass of the conductive particles. The remaining component in the conductive composition is preferably conductive particles. If there is no problem with pattern formability, the conductive composition may not contain a resin component. From the viewpoint of improving conductivity, it is preferable that the conductive composition does not substantially contain a curable component other than the conductive particles. On the other hand, from the viewpoint of improving the pattern formability, i.e., the printability and coatability of the conductive composition, the conductive composition may contain a resin component such as a resin or a binder. From the viewpoint of fully obtaining the effect of using the resin component, the amount of the resin component in the conductive composition is preferably 1 to 15 parts by mass, more preferably 1 to 10 parts by mass, even more preferably 1 to 5 parts by mass, and particularly preferably 2 to 5 parts by mass, per 100 parts by mass of the conductive particles. The remaining components in the conductive composition are preferably other components such as conductive particles. Specific examples of resin components that can be contained in the conductive composition include polyvinylpyrrolidone, polyester, epoxy resin, (meth)acrylic resin, polyvinyl acetal, cellulose resin (e.g., ethyl cellulose), and phenol resin.

[0059] The conductive composition may contain a solvent. When the conductive composition contains a solvent, the conductive composition can be easily applied or printed onto a substrate. The solvent typically contains an organic solvent. The solvent may contain water as long as the conductive particles can be appropriately dispersed in the solvent. The type of solvent is not particularly limited, as long as it does not substantially alter the components in the conductive composition. The amount of the solvent used may be adjusted as appropriate depending on the coating / printing method of the conductive composition, etc. The amount of the solvent used is, for example, 3 to 30 mass %, preferably 5 to 25 mass %, and more preferably 10 to 20 mass % of the total conductive composition.

[0060] The specific embodiment of the conductive particles contained in the conductive composition is as described above, and therefore will not be described again.

[0061] From the viewpoint of further reducing the resistivity of the final conductive pattern, it is preferable that the proportion of conductive particles in the conductive composition is high. Specifically, the proportion of conductive particles in the total non-volatile components of the conductive composition is preferably 95% by mass or more, more preferably 97% by mass or more, even more preferably 98% by mass or more, and particularly preferably 99% by mass or more. In other words, from the viewpoint of further reducing the resistivity of the resulting conductive pattern, it is preferable that the conductive composition is substantially free of resin components such as resins and binders. Here, "substantially free of resin components" means that the composition does not contain any resin components at all, or that the amount of resin components contained is so small that the expected effect of using the resin components cannot be obtained (for example, 1% by mass or less, specifically 0.5% by mass or less, of the total non-volatile components of the conductive composition). The conductive composition does not need to contain resins or binders as long as the desired conductive pattern can be obtained.

[0062] The conductive composition may or may not contain various additive components found in conventional ink compositions and conductive pastes.

[0063] (Formation of an adhesive layer on a substrate: Figure 2A) 2A is a diagram showing an adhesive layer 2 provided on the surface of a substrate 1 different from the easily peelable substrate 5. If the adhesive layer 2 is curable, it will correspond to the cured resin layer in FIG. 1 after curing.

[0064] The substrate 1 is usually in the form of a film, sheet or plate, and from the viewpoint of industrial productivity, the shape of the substrate 1 is preferably any of these. The substrate 1 is preferably flexible. By employing a flexible substrate 1, a flexible printed circuit (FPC) can be manufactured. By using a flexible substrate 1, pressing using a "roll" becomes easier in the pressing step described below. This is preferable from the viewpoint of mass production. Just to be clear, the substrate 1 may be a rigid substrate that does not have flexibility. The thickness of the substrate 1 is not particularly limited and can be appropriately set depending on the final use (electronic device, RF tag, electromagnetic wave shielding film, planar heating element, etc.) described below and various other circumstances. The thickness of the substrate 1 is typically 10 to 250 μm, preferably 30 to 100 μm. However, from the viewpoint of suppressing the occurrence of curling, it is preferable that the substrate 1 is somewhat thick. Specifically, the thickness of the substrate 1 is preferably 100 to 250 μm, more preferably 100 to 150 μm. The substrate 1 may have a single layer structure or a laminated structure of two or more layers.

[0065] Considering cost and end use, the substrate 1 is preferably at least one selected from the group consisting of polyesters such as PET (polyethylene terephthalate) and PEN (polyethylene naphthalate), polyolefins such as polyethylene and polypropylene, polycarbonate, polyimide, and paper. Here, the paper may be coated paper (paper whose surface is coated with a coating agent) or ordinary uncoated paper. Furthermore, the substrate 1 is not limited to PET and other materials, and general resin films can also be used. Furthermore, the substrate 1 may be transparent or opaque. Examples of opaque resin films include foamed resin films such as foamed PET film and foamed resin sheets. In the pressing step, if a conductive pattern with sufficiently low resistivity can be obtained without heating or by heating at a relatively low temperature, a low heat-resistant substrate 1 such as polyester, polyolefin, polycarbonate, paper, etc. can also be suitably used as the substrate. Furthermore, when a highly heat-resistant substrate 1 such as polyimide is used, the resistivity of the resulting conductive pattern can be further reduced by performing high-temperature heating in the pressing step.

[0066] The adhesive layer 2 is preferably thermosetting or photosetting. More preferably, the adhesive layer 2 is formed from a thermosetting resin material or a photosetting resin material. When the substrate 1 is light-transmitting, the adhesive layer 2 can be photosetting, so that the adhesive layer 2 can be cured by irradiating light from the substrate 1 side. When the substrate 1 is not light-transmitting, the adhesive layer 2 can be thermosetting, so that the adhesive layer 2 can be cured by heating. Just to be clear, the adhesive layer 2 may have both thermosetting and photocuring properties, or may have only one of the thermosetting and photocuring properties.

[0067] Various thermosetting or photocurable resin materials can be used as materials for forming the adhesive layer 2. Specific examples include thermosetting or photocurable resin materials such as epoxy resin-containing materials, polymerizable (meth)acrylate-containing materials, urethane-based materials, urethane (meth)acrylate-containing materials, and silicone-based materials. The adhesive layer 2 can also be made of a commercially available product. For example, the adhesive layer 2 can be made of various thermosetting or photocurable resin materials that are known or commercially available as hard coating agents. In addition, various thermosetting or photocurable resin materials that are known or commercially available as primers can also be used.

[0068] When the adhesive layer 2 is thermosetting, it is preferable to form the adhesive layer 2 so that the thermosetting proceeds at a heating temperature that does not damage the substrate 1. For example, when the substrate 1 is made of a resin, it is preferable to design the adhesive layer 2 so that the curing reaction proceeds sufficiently when heated at a temperature lower than the glass transition temperature of the resin.

[0069] At the stage shown in Figure 2A, adhesive layer 2 is preferably in an uncured or semi-cured state, more preferably in an uncured state. By leaving the adhesive layer in an uncured or semi-cured state, it is believed that in the transfer process described below, a portion of adhesive layer 2 penetrates into the gaps between the conductive particles in the temporary pattern (pattern 3B), forming a conductive pattern where ε0 < ε1. This penetration is also believed to contribute to further improving the adhesion of the final conductive pattern.

[0070] The thickness of adhesive layer 2 is not particularly limited, but considering the need to obtain sufficient adhesiveness and to appropriately control penetration into the temporary pattern, it is preferably 1 to 30 μm, and more preferably 5 to 15 μm. The thickness of adhesive layer 2 is thought to be related to the cross-sectional shape of the conductive pattern and the degree to which the conductive pattern is embedded in the substrate. Therefore, it is preferable to appropriately adjust the thickness of adhesive layer 2. The adhesive layer 2 may be a single layer or may be two or more layers. For example, if the substrate 1 is paper, a two-layer adhesive layer 2 may be used in consideration of penetration into the fibrous paper. In this case, the first adhesive layer closest to the paper plays the role of "sealing."

[0071] (Transfer process: Figure 3B) In the transfer step, a temporary pattern (pattern 3B) as shown in Figure 2P2 is brought into contact with an adhesive layer 2 provided on the surface of the substrate 1. This causes the temporary pattern (pattern 3B) to be transferred to the surface of the adhesive layer 2, resulting in a transferred pattern (pattern 3B). In the transfer step, pressing may or may not be performed to improve adhesion between the temporary pattern (pattern 3B) and the adhesive layer 2. As long as the temporary pattern (pattern 3B) is properly separated from the easily peelable substrate 5 at an appropriate stage, pressing may or may not be performed. When pressing, care should be taken to minimize changes in the shape of the temporary pattern (pattern 3B). From the viewpoint of improving adhesion, pressing is usually preferable. Incidentally, in the examples described below, after the temporary pattern and the adhesive layer are brought into contact, pressing is performed using a roller from the side of the easily peelable substrate 5. In addition to pressing using a roller, pressing using a flat press is also possible. If the adhesive layer 2 is uncured or semi-cured, it is believed that during this transfer step, a portion of the adhesive layer 2 penetrates into the gaps between the conductive particles in the temporary pattern (pattern 3B), and a conductive pattern with ε0 < ε1 is formed after the pressing step described below. This penetration is also believed to contribute to further improving the adhesion of the final conductive pattern. Incidentally, the fact that the particle size of the conductive particles is on the order of μm is thought to contribute to the appropriate penetration here. If the particle size of the conductive particles is on the order of nm, the gaps between the conductive particles will be very small, so the amount of penetration into the adhesive layer 2 will be small, and the values ​​of ε0 and ε1 may change little or not at all. Also, if the particle size of the conductive particles is too large, the amount of penetration into the adhesive layer 2 will be too great, which may result in little or no change in the values ​​of ε0 and ε1, or ε1 not being 65% or more.

[0072] (Adhesive layer curing process: Figure 3C) Between the transfer step and the pressing step, it is preferable to carry out an adhesive layer curing step to promote curing of the adhesive layer 2. This hardens the adhesive layer 2, which tends to further increase adhesion between the temporary pattern (pattern 3B) and the cured adhesive layer 2B formed by curing the adhesive layer 2. The cured adhesive layer 2B corresponds to the resin layer in FIG. The adhesive layer 2 can be cured by light such as ultraviolet light if the adhesive layer 2 is photocurable. Alternatively, the adhesive layer 2 can be cured by heating if the adhesive layer 2 is thermosetting. FIG. 3C shows an embodiment in which the adhesive layer 2 is cured by ultraviolet (UV) irradiation from the transparent substrate 1 side. The conditions for light irradiation and heating may be adjusted and optimized as appropriate depending on the specific material that constitutes the adhesive layer 2. However, when curing the adhesive layer 2 by heating, care must be taken to avoid damaging the substrate 1 with heat.

[0073] In the adhesive layer curing step, it is preferable to completely cure the adhesive layer 2, but it is also possible to cure it to a certain extent without completely curing it. In either case, it is sufficient to improve the adhesion between the temporary pattern (pattern 3B) and the cured adhesive layer 2B obtained by curing the adhesive layer 2.

[0074] (Peeling process: Figure 3D) Before the pressing step described below, a peeling step of peeling the easily peelable substrate 5 from the pattern 3B is preferably carried out. Just to be clear, in Figure 3, the peeling step is depicted between the adhesive layer hardening step (C) and the oxide film removal step (E), but as long as a substrate having the desired conductive pattern is ultimately obtained, the peeling step may also be performed, for example, between the transfer step (B) and the adhesive layer hardening step (C). As long as the easily peelable substrate 5 can be appropriately peeled from the pattern 3B, the specific peeling method and conditions are not particularly limited.

[0075] (Oxide film removal process: Figure 3E) After the transfer step, it is preferable to carry out an oxide film removal step in which a component X capable of removing an oxide film on the surface of the conductive particles is brought into contact with the transferred pattern (pattern 3B) before or simultaneously with the pressing step described below. By carrying out the oxide film removal step, sintering of the conductive particles is facilitated in the pressing step described below, and the conductivity of the finally obtained conductive pattern tends to be further enhanced.

[0076] It is preferable that component X penetrates into the interior of the transfer pattern (pattern 3B) through the gaps between the conductive particles that make up the transfer pattern (pattern 3B). This tends to further increase the conductivity of the finally obtained conductive pattern. For this reason, in the oxide film removal step, the transfer pattern (pattern 3B) in contact with component X may be pressed to promote penetration of component X into the interior of the transfer pattern (pattern 3B). In this case, the oxide film removal step and the pressing step described below may be performed simultaneously. Of course, the oxide film removing step may be performed as a separate step from the pressing step.

[0077] The oxide film removal step can be carried out by contacting, and preferably penetrating, a liquid 7 containing component X, capable of removing oxide films on the surfaces of conductive particles, into the transfer pattern (pattern 3B), as shown in FIG. 3E. While FIG. 2E shows an embodiment in which the liquid 7 containing component X is dropped or sprayed onto the transfer pattern (pattern 3B), the transfer pattern (pattern 3B) may also be immersed in the liquid containing component X. Alternatively, the liquid 7 containing component X may be brought into contact with the embedded pattern (pattern 3B) using an inkjet method or a dispenser method. The liquid containing component X is preferably water in which component X is dissolved or dispersed. The use of water is preferred from the viewpoints of reducing the environmental load and process safety (non-flammability). Of course, an organic solvent in which component X is dissolved or dispersed can also be used. Instead of using a liquid containing component X, the oxide film removal step may be carried out by bringing component X in a gaseous state into contact with the transfer pattern (pattern 3B). It is also conceivable to bring a sheet containing component X into contact with pattern 3B, preferably by applying pressure, thereby causing component X to permeate into pattern 3B. Specific examples of the sheet here include paper or nonwoven fabric containing component X, and resin sheets having component X coated or printed on their surfaces. Additionally, the method for contacting and permeating component X into the transfer pattern (pattern 3B) is not particularly limited.

[0078] Component X is not particularly limited as long as it is capable of removing the oxide film on the surface of the conductive particles. In this specification, "removal" of an oxide film includes not only the removal of the oxide itself present on the surface of a conductive particle, but also the case where the oxide undergoes a chemical change such as reduction, thereby returning the oxide to a non-oxide.

[0079] According to the findings of the present inventors, it is preferable to include at least one selected from the group consisting of organic acids, phosphorus oxoacids, and hydrazine or its derivatives, which are particularly suitable when the conductive particles include copper or silver.

[0080] Examples of organic acids include carboxylic acids such as citric acid, formic acid, acetic acid, malonic acid, malic acid, tartaric acid, ascorbic acid, succinic acid, fumaric acid, and propionic acid. Specific examples of phosphorus oxoacids include phosphinic acid, phosphonic acid, phosphorous acid, phosphoric acid, diphosphoric acid, triphosphoric acid, and metatriphosphoric acid. Of these, phosphinic acid is particularly preferred. Examples of hydrazine or its derivatives include hydrazine itself; hydrazine salts such as hydrazine monohydrochloride, hydrazine dihydrochloride, hydrazine monohydrobromide, and hydrazine sulfate; and other compounds having an -NH-NH2 structure.

[0081] Additionally, from the viewpoint of removing an oxide film, a compound having a small pKa in water can be used as component X. Specifically, a compound having a pKa in water of -5.0 to 5.0 is preferred as component X, and a compound having a pKa of -4.0 to 4.5 is more preferred as component X. Incidentally, when component X is a polybasic acid, it is preferred that the smallest pKa among the multiple pKas is within the above range. Considering only the small pKa and the resulting ability to remove oxide films, it is conceivable to use an inorganic acid such as hydrochloric acid, nitric acid, or sulfuric acid as component X. However, taking into consideration the inconvenience that may occur if the acid remains in pattern 3B, an organic acid is preferred as component X. The pKa value used here can be a value at room temperature (e.g., 25°C). However, from the viewpoint of the removability of the oxide film in the actual process, it can be said that it is preferable to use a pKa value at the temperature in the penetration step or conductive film formation step.

[0082] Additionally, any compound capable of returning an oxide film to a non-oxidized state by a reduction reaction can also be used as component X. For example, a compound having an aldehyde group can be used as component X because it may be able to reduce an oxide.

[0083] Furthermore, compounds that have a small pKa in water and can return an oxidized film to a non-oxidized state through a reduction reaction are also preferably used as component X. An example of such a compound is formic acid. Formic acid has the advantage that it is easily volatile and therefore does not easily remain in the pattern.

[0084] In addition to the above, examples of component X include pyrogallol, phenidone, hydroquinone, and orthoaminophenol, which are known to function as reducing agents in the field of silver halide photography. If a conductive pattern having a lower resistivity can be obtained by infiltrating a certain compound A into pattern 3B compared to a conductive pattern without infiltrating the compound A, then the compound A can be used as component X.

[0085] When a liquid in which component X is dissolved or dispersed is brought into contact with pattern 3B, the concentration of component X in the liquid may be adjusted as appropriate. The concentration may be adjusted from the viewpoints of allowing a sufficient amount of component X to penetrate into pattern 3B and reducing the amount of residual component X to suppress corrosion or deterioration of the conductive pattern. The concentration of component X in the liquid is, for example, 0.05 to 50 mol / L, preferably 0.1 to 40 mol / L, more preferably 0.1 to 30 mol / L, even more preferably 0.1 to 10 mol / L, and particularly preferably 0.15 to 5.0 mol / L. Of course, a liquid containing component X at a concentration lower than the concentrations shown here may be used, or a liquid containing component X at a concentration higher than the concentrations shown here (for example, saturation concentration) may be used.

[0086] When performing an oxide film removal step, it is preferable to press at least the transfer pattern (pattern 3B) before the oxide film removal step, specifically after the peeling step and before the oxide film removal step. This makes it easier to maintain the shape of the transfer pattern (pattern 3B) during the oxide film removal step. In particular, when a liquid in which component X is dissolved or dispersed is allowed to penetrate into the transfer pattern (pattern 3B) during the oxide film removal step, it is easier to prevent at least a portion of the transfer pattern (pattern 3B) from being deformed or collapsed by the liquid. In particular, when a conductive composition substantially free of a resin component is used, the transfer pattern (pattern 3B) is prone to deformation and collapse, so pressing as described herein is preferable. In other words, when a conductive composition containing a resin component is used, the transfer pattern (pattern 3B) is less prone to deformation and collapse than a conductive composition substantially free of a resin component, so the shape of the transfer pattern (pattern 3B) may be sufficiently maintained even without pressing.

[0087] When pressing the transfer pattern (pattern 3B) before the oxide film removal step, the method can be performed, for example, as described in the pressing step (FIG. 3F) described later. However, it is preferable that the pressure be appropriately adjusted. From the viewpoint of maintaining the shape of the transfer pattern (pattern 3B), a high pressure is preferable. However, from the viewpoint of the permeability of component X, it is preferable that there be an appropriate gap between the conductive particles, so it is preferable that the pressure is not too high.

[0088] Specifically, the pressure applied to the transfer pattern (pattern 3B) in the pressing process before the oxide film removal process is P firstIn the conductive film forming process described later, the pressure applied to the transfer pattern (pattern 3B) is P second When P first <P second More specifically, P first HA P second It is preferable that the pressure in the pressing step is 0.9 times or less, more preferably 0.75 times or less, and even more preferably 0.6 times or less. In other words, it is preferable that the pressure in the pressing step is sufficiently smaller than the pressure required to compress and sinter the conductive particles together in the pressing step.

[0089] From various perspectives, P first and P second It is preferable to optimize each of these values. P first is preferably 1 to 500 MPa, more preferably 10 to 200 MPa, and even more preferably 20 to 100 MPa. first By setting the pressure to 1 MPa or more, it is easy to reliably and sufficiently obtain the effect of easily maintaining the shape of the transfer pattern (pattern 3B) in the subsequent process. first By making the pressure at most 500 MPa, sufficient gaps for the penetration of component X tend to remain in the transfer pattern (pattern 3B). Also, P second is, for example, 1 MPa or more, preferably 10 MPa or more, more preferably 10 to 5000 MPa, even more preferably 20 to 1000 MPa, particularly preferably 30 to 300 MPa, and especially preferably 50 to 250 MPa. second By setting the pressure to a certain value, the resistivity of the conductive pattern obtained at the end can be further reduced. In addition, by not applying too much pressure, damage to the substrate 1 and the transfer pattern (pattern 3B) can be suppressed. Incidentally, if the strength of the substrate 1 is sufficient, the pressure can be increased to further reduce the resistivity of the conductive pattern obtained at the end.

[0090] (Pressing process: Figure 3F) In the pressing step, at least pressure is applied to the transfer pattern (pattern 3B). This increases the conductivity of the transfer pattern (pattern 3B) to obtain the conductive pattern 3C. Preferably, the pressing step sinters the conductive particles in the transfer pattern (pattern 3B).

[0091] As shown in Figure 3F, the pressure is preferably applied by covering the exposed surface of the transfer pattern (pattern 3B) with member 6 and then at least pressurizing the transfer pattern (pattern 3B). As an example, the pressure can be applied by sandwiching a laminate of the substrate 1, cured adhesive layer 2B, transfer pattern (pattern 3B), and member 6 between two opposing rolls 10A and 10B and transporting the laminate between the two rolls. Member 6 is preferably a film-like material. In Fig. 3F, liquid 7 containing component X, which can remove the oxide film on the surface of the conductive particles as described in Fig. 3E, is present above the transfer pattern (pattern 3B). In this case, it is thought that component X penetrates into the transfer pattern (pattern 3B) by applying pressure, removing the oxide film from the conductive particles while simultaneously sintering the conductive particles. In other words, Figs. 3E and 3F can be said to represent an embodiment in which the oxide film removal process and the pressing process are performed simultaneously.

[0092] From one viewpoint, the material of the member 6 can be the same as that of the base material 1. That is, the member 6 can be preferably a polyester film such as a PET film. From another perspective, in order to prevent peeling or damage to the transfer pattern (pattern 3B), an easily peelable film or release paper can be preferably used as the member 6. A specific example of the easily peelable film or release paper is the easily peelable substrate 5 mentioned in FIG.

[0093] On the other hand, in order to simplify the manufacturing process by reducing the amount of process materials and reduce waste, pressurization may be performed without using the member 6.

[0094] In the pressing step, it is preferable to apply pressure to the transfer pattern (pattern 3B) while heating it, which tends to improve the conductivity of the conductive pattern 3C. Preferably, the transfer pattern (pattern 3B) is pressed at a pressure of 50 to 300 MPa and heated at a temperature of 80 to 150°C. When the pressing step is performed using two opposing rolls 10A and 10B as shown in FIG. 3F, it is preferable to use rolls with built-in heaters that can adjust the temperature.

[0095] (Other optional processes) The manufacturing method of Example 1 may include steps other than those described above. For example, if the member 6 is used in the pressing step, the member 6 is removed after the pressing step is completed. Furthermore, for example, after the pressing step, a removal step may be performed to remove component X remaining on the surface or inside the obtained conductive pattern. Specific examples include a step of immersing the substrate provided with the obtained conductive pattern in a liquid (water or an organic solvent) capable of dissolving or dispersing component X, or a step of pouring a liquid (water or an organic solvent) onto the surface of the conductive pattern to wash away the remaining component X. Another possible step is to vaporize and remove the remaining component X by heating the substrate provided with the obtained conductive pattern at a temperature that does not damage the substrate 1.

[0096] [Example 2] A preferred method for producing a substrate having a conductive pattern of this embodiment, which is different from Example 1, is as follows: an embedding step of bringing a temporary pattern formed on the surface of an easily peelable substrate using a conductive composition containing conductive particles into contact with a resin-containing layer formed on the surface of a substrate different from the easily peelable substrate, thereby obtaining an embedded pattern in which at least a portion of the temporary pattern is embedded in the resin-containing layer; a pressing step of applying at least pressure to the embedded pattern to obtain a conductive pattern; Includes:

[0097] The manufacturing method will be described in more detail below with reference to FIGS. (Formation of temporary patterns on the surface of an easily peelable substrate: Figure 4P1, Figure 4P2) First, a temporary pattern is formed on the surface of an easily peelable substrate using a conductive composition containing conductive particles. Specifically, first, as shown in Fig. 4P1, a pattern 30 made of a conductive composition containing conductive particles, typically in the form of a paste containing a solvent, is formed on the surface of an easily peelable substrate 50. Thereafter, by volatilizing the solvent in the pattern 30, a temporary pattern (pattern 30B) can be obtained on the easily peelable substrate 50, as shown in Fig. 4P2.

[0098] The method for forming the pattern 30 is not particularly limited. Various coating and printing techniques can be applied. The pattern 30 may be formed on the entire surface of the easily peelable substrate 50 or on only a portion of the surface of the easily peelable substrate 50. In the former case, the pattern 30 can be formed by coating using a device such as a blade coater, air knife coater, doctor coater, roll coater, bar coater (rod coater), or curtain coater. In the latter case, the pattern 30 can be formed by various printing methods, such as screen printing, gravure printing, letterpress printing, lithographic printing (offset printing), inkjet printing, and transfer printing. By appropriately designing the "pattern" during printing, it is possible to produce a substrate having a pattern structure, such as a conductive film (circuit pattern) that can function as a circuit or a mesh pattern with electromagnetic wave shielding properties. When the pattern 30 is formed on only a portion of the surface of the easily peelable substrate 50, it is preferable that the printing "pattern" be appropriately designed depending on the intended use of the substrate having the final conductive pattern. To prevent the pattern 30 from being formed in any location other than the desired location on the easily peelable substrate 50, for example, a film with holes cut out therein may be placed on the easily peelable substrate 50, a conductive composition may be applied or printed on top of the film, and then the film may be removed.

[0099] The easily peelable substrate 50 is not particularly limited as long as it can be easily peeled in the peeling step described below, that is, as long as the temporary pattern (pattern 30B) can be easily separated. The specific embodiment of the easily peelable substrate 50 can be the same as the easily peelable substrate 5 in Example 1. Therefore, a separate explanation will not be given. The easily peelable substrate 50 may be disposable or may be reused.

[0100] The easily peelable substrate 50 may be in the form of a film or sheet as shown in FIG. 4P1 or FIG. 4P2, or may be in the form of a roll, for example. The surface of the easily peelable substrate 50 is usually flat. These points are also similar to those of the easily peelable substrate 5 in Example 1. When the easily peelable substrate 50 is in the form of a film or sheet, its thickness is also similar to that of the easily peelable substrate 5 in Example 1.

[0101] The heating conditions for volatilizing the solvent in pattern 30 to obtain a temporary pattern (pattern 30B) are similar to the heating conditions for volatilizing the solvent in pattern 3 in [Example 1] to obtain a temporary pattern (pattern 3B).

[0102] The height of the provisional pattern (pattern 30B) is preferably 0.5 to 100 μm, more preferably 5 to 60 μm, and even more preferably 10 to 40 μm. When this height is 0.5 μm or more, the conductivity of the final conductive pattern can be improved. On the other hand, when this height is 100 μm or less, the entire substrate provided with the final conductive pattern can be made thinner. This is preferable, for example, from the viewpoint of miniaturization and weight reduction of electronic devices.

[0103] It is preferable that the conductive particles in the temporary pattern (pattern 30B) are not substantially sintered, although the conductive particles are usually sintered in the pressing step described below. Furthermore, it is preferable that the temporary pattern (pattern 30B) is substantially uncured. Specifically, even if the conductive composition contains a curable resin, a crosslinking agent, or the like, it is preferable that the curable resin or crosslinking agent in the temporary pattern (pattern 30B) is substantially unreacted before the pressing step. Alternatively, the temporary pattern may not contain a curable resin component such as a curable resin or a crosslinking agent in the first place.

[0104] The conductive composition for forming the temporary pattern (pattern 30B) is preferably in a paste state at room temperature (for example, 25° C.) from the viewpoints of ease of pattern formation and shape retention. The conductive particles contained in the conductive composition have already been described, and therefore will not be described again. The specific aspects of the conductive composition (components, amounts, etc.) can be the same as those of the conductive composition described in Example 1, and therefore will not be described again.

[0105] By the way, D 50 By setting ε0 to an appropriate value (on the order of μm), the possibility that a portion of the resin-containing layer 20 will penetrate into the gaps between the conductive particles in the temporary pattern (pattern 30B) during the filling process described below is increased. This is thought to contribute to appropriately reducing ε0 and obtaining a conductive pattern in which ε0<ε1. This is also thought to lead to improved adhesion of the final conductive pattern. With nano-sized conductive particles, it is unlikely that a portion of the resin-containing layer 20 will penetrate into the gaps between the conductive particles.

[0106] (Formation of a resin-containing layer on a substrate surface: Figures 4A, 4B, and 4C) 4A, 4B, and 4C show an example of a process for providing a resin-containing layer 20 on the surface of the substrate 10. Here, the process is shown in which a resin-containing layer 20 previously formed into a film is attached to the surface of the substrate 10 to provide the resin-containing layer 20 on the surface of the substrate 10. If the resin-containing layer 20 is curable, after curing, it will correspond to the cured resin layer in FIG. Just to be clear, the resin-containing layer 20 may be provided by a method other than laminating a film. For example, the resin-containing layer 20 may be provided by applying or printing a resin-containing coating liquid onto the surface of the substrate 10. Furthermore, in order to adjust and optimize the thickness of the resin-containing layer 20, the resin-containing layer 20 may be provided by laminating two or more films or by applying or printing two or more resin-containing coating liquids.

[0107] 4A, a resin-containing layer 20 having release sheets 60 attached to both sides thereof is prepared, and one of the release sheets 60 attached to both sides thereof is peeled off. The specific method for peeling off the release sheet 60 is not particularly limited.

[0108] 4B, one side of the resin-containing layer 20 exposed by peeling off the release sheet 60 is brought into contact with the surface of the substrate 10. Then, the resin-containing layer 20 is attached to the surface of the substrate 10. At this time, it is preferable to increase the adhesion (adhesion strength) between the substrate 10 and the resin-containing layer 20 by sandwiching the substrate 10, the resin-containing layer, and the release sheet 60 between, for example, two opposing rolls 100A and 100B and transporting them between the two rolls.

[0109] By peeling off the release sheet 60 in Fig. 4B, it is possible to obtain the substrate 10 having the resin-containing layer 20 provided on the surface of the substrate, as shown in Fig. 4C. The specific method for peeling off the release sheet 60 here is not particularly limited.

[0110] The resin-containing layer 20 is preferably curable. Specifically, the resin-containing layer 20 can be cured by an external stimulus such as light or heat, which causes a curing reaction such as a crosslinking reaction to proceed. The "light" here is preferably ultraviolet light. The resin-containing layer 20 may be one that hardens in response to light alone, one that hardens in response to heat alone, or one that hardens in response to both light and heat.

[0111] The resin-containing layer 20 can be formed, for example, by attaching a curable film-like resin material to one surface of the substrate 10. For example, commercially available OCA (Optically Clear Adhesive) films, die attach films, and the like can be preferably used to form the resin-containing layer 20. Of course, instead of using a film-like resin material, the resin-containing layer 20 may be provided on one side of the substrate 10 by coating or printing. For example, various adhesives (preferably photocurable and / or thermosetting) known for use in the manufacture of electronic devices can be preferably used to form the resin-containing layer 20. In terms of chemical composition, the resin-containing layer 20 is preferably made of a (meth)acrylic resin-based curable material or an epoxy resin-based curable material.

[0112] The thickness of the resin-containing layer 20 is not particularly limited, but is usually 3 to 50 μm, preferably 10 to 30 μm, from the viewpoint of embedding the temporary pattern (pattern 30B) sufficiently deeply and reducing the influence of curing shrinkage and the like. In terms of the relationship with the height of the provisional pattern (pattern 30B), in order to properly embed the provisional pattern (pattern 30B), the height of the provisional pattern (pattern 30B) is set to H i When the thickness of the resin-containing layer is T, H i / T is preferably 2 or less, more preferably 1 to 2, and even more preferably 1 to 1.5.

[0113] The substrate 10 can be the same as the substrate 1 in Example 1, and therefore will not be described again.

[0114] (Embedding step: Figure 5D) In the embedding step, the temporary pattern (pattern 30B) provided on the surface of the easily peelable substrate 50, obtained, for example, as described above, is brought into contact with the resin-containing layer 20 provided on the surface of the substrate 10. Then, an embedded pattern (pattern 30B) is obtained in which at least a portion of the temporary pattern (pattern 30B) is embedded in the resin-containing layer 20. 5D , the entire temporary pattern (pattern 30B) is embedded in the resin-containing layer 20. That is, the distance from the interface between the substrate 10 and the resin-containing layer 20 to the furthest part of the pattern 30B can be equal to or less than the maximum thickness of the resin-containing layer 20.

[0115] In the embedding step, it is preferable to apply pressure to sufficiently embed the temporary pattern (pattern 30B) in the resin-containing layer 20. For example, as shown in Fig. 5D, it is preferable to embed the temporary pattern (pattern 30B) in the resin-containing layer 20 by sandwiching a laminate of the substrate 10, the resin-containing layer 20, the temporary pattern (pattern 30B), and the easily peelable substrate 50 between two opposing rolls 120A and 120B and transporting the laminate between the two rolls. The pressure of the pressing is preferably 0.5 to 3 MPa, more preferably 0.5 to 2 MPa, in consideration of sufficient embedding of the provisional pattern and suppression of deformation of the provisional pattern.

[0116] In the embedding step, the resin-containing layer 20 is preferably softened by heat. This allows the temporary pattern (pattern 30B) to be embedded in the resin-containing layer 20 more smoothly while further suppressing changes in its shape and dimensions. This is thought to enable the formation of thinner / higher-precision circuit patterns. The resin-containing layer 20 can be softened by selecting an appropriate material for forming the resin-containing layer 20 and applying appropriate heating in the embedding step. Additionally, the resin-containing layer 20 may be softened by preheating before the embedding step. In other words, the resin-containing layer 20 may be softened by heat at the stage of FIG. 4B or FIG. 4C. Incidentally, according to the knowledge of the present inventors, among commercially available OCA films and die attach films, there are some that become softer than room temperature when heated to about 50 to 100° C., and harden as a result of a curing reaction when heated to above 100° C. A resin-containing layer 20 having such properties is particularly preferable. Whether the resin-containing layer 20 softens due to heating in the embedding process can be determined, for example, by measuring the viscoelastic properties of the material (film, etc.) that forms the resin-containing layer 20 while increasing the temperature.

[0117] When the resin-containing layer 20 has the property of being softened by heating, the heating conditions for softening the resin-containing layer 20 may be appropriately set based on the chemical structure and properties of the material constituting the resin-containing layer 20. The heating temperature for softening the resin-containing layer 20 may be 60 to 120°C, specifically 70 to 100°C.

[0118] (Curing step: Figure 5E) If the resin-containing layer 20 is curable, it is preferable to carry out a curing step between the above-mentioned embedding step and the pressing step described below to cure or semi-cure the resin-containing layer 20 to form the cured resin layer 20B. 5, the curing step is described between the embedding step (D) and the peeling step (F). However, if the curing step is performed, it is sufficient that the curing step is performed between the embedding step (D) and immediately before the pressing step (H) described below.

[0119] When the resin-containing layer 20 is curable, the resin-containing layer 20 remains uncured (i.e., relatively soft) until the embedding process is completed, and therefore the temporary pattern (pattern 30B) can be smoothly embedded in the resin-containing layer 20 while suppressing changes in its shape and dimensions, thereby forming an embedded pattern (pattern 30B). The resin-containing layer 20 is cured or semi-cured (harder than when uncured) just before the pressing step, and the resin-containing layer 20 becomes the cured resin layer 20B. This effectively limits deformation of the pattern 30B when pressure is applied to the pattern 30B in the pressing step. In other words, the cured resin layer 20B functions as a "wall" that effectively suppresses deformation of the pattern 30B. This makes it easier to obtain thinner conductive patterns and conductive patterns with higher precision (closer to the intended dimensions and shape). From the viewpoint of suppressing deformation of the pattern 30B during the pressing step, it is preferable that the resin-containing layer 20 be cured (substantially completely cured). In other words, it is preferable that the cured resin layer 20B is a substantially completely cured product of the curable resin material. Here, "substantially completely cured product" means that it does not contain any reactive groups other than reactive groups (crosslinkable groups, polymerizable groups, etc.) that inevitably remain even when a sufficient amount of external stimulus (heat, light, etc.) is applied to the curable resin material. However, the cured resin layer 20B may be in a semi-cured state as long as it functions as a "wall" that suppresses deformation of the pattern 30B during the pressing step.

[0120] When the resin-containing layer 20 is curable, the resin-containing layer 20 remains uncured until the completion of the embedding step, which is thought to facilitate the penetration of resin components into some of the voids between the conductive particles that make up the pattern 30B. This is thought to contribute to appropriately reducing ε0 and obtaining a conductive pattern in which ε0 < ε1. Furthermore, it is thought that the penetration of resin components into some of the voids between the conductive particles and the curing of the resin components further improves the adhesion between the substrate and the pattern.

[0121] The specific method for curing or semi-curing the resin-containing layer 20 to form the cured resin layer 20B is not particularly limited. If the resin-containing layer 20 is thermosetting, the resin-containing layer 20 may be heated. If the resin-containing layer 20 is photocurable, the resin-containing layer 20 may be irradiated with light (typically ultraviolet light). If the resin-containing layer 20 is photocurable and the substrate 10 is light-transmitting, the resin-containing layer 20 can be cured or semi-cured by irradiating it with light from the substrate 10 side. Of course, light may be irradiated from the resin-containing layer 20 side, but in this case, it may be necessary to increase the amount of light irradiated or irradiate it at an angle so that the light reaches below the pattern 3B, taking into account that some of the light is blocked by the pattern 3B. When the resin-containing layer 20 is thermosetting, the heating temperature and time may be adjusted appropriately taking into consideration the ease of thermosetting of the resin-containing layer 20 and the heat resistance of the substrate 10. When the resin-containing layer 20 is thermosetting, the heating temperature and time are, for example, 80 to 150°C, 1 to 30 minutes, specifically 100 to 120°C, and 5 to 20 minutes. Of course, the heating temperature and time do not have to be within these numerical ranges. When the resin-containing layer 20 is photocurable, the amount of light irradiation is, for example, an integrated amount of UVA light of 100 to 6000 mJ / cm 2 2 Specifically, 200 to 3000 mJ / cm 2 Of course, the amount of light irradiation does not have to be within this range.

[0122] (Peeling process: Figure 5F) Before the pressing step described below, it is preferable to carry out a peeling step of peeling the easily peelable substrate 50 from the pattern 30B. Just to be clear, in FIG. 5, the peeling step is depicted immediately before the oxide film removal step (G), but the peeling step may be performed, for example, between the embedding step (D) and the curing step (E) as long as a substrate having a desired conductive pattern is ultimately obtained. As long as the easily peelable substrate 50 is appropriately peeled from the pattern 30B, the specific peeling method and conditions are not particularly limited.

[0123] (Oxide film removal process: Figure 5G) It is preferable to include an oxide film removal step, which is performed after the embedding step and before or simultaneously with the pressing step described below, in which a component X capable of removing an oxide film on the surface of the conductive particles in the embedded pattern (pattern 30B) is penetrated into the embedded pattern (pattern 30B). By performing the oxide film removal step, sintering of the conductive particles tends to proceed more easily in the pressing step described below, and the conductivity of the finally obtained conductive pattern tends to be further increased.

[0124] It is preferable that component X penetrates into the embedded pattern (pattern 30B) through the gaps between the conductive particles that make up the embedded pattern (pattern 30B). This tends to further increase the conductivity of the finally obtained conductive pattern. For this reason, in the oxide film removal step, the embedded pattern (pattern 30B) in contact with component X may be pressed to promote penetration of component X into the embedded pattern (pattern 30B). In this case, the oxide film removal step and the pressing step described below may be performed simultaneously. Of course, the oxide film removing step may be performed as a separate step from the pressing step.

[0125] The oxide film removal step can be performed, for example, as shown in FIG. 5G, by contacting and preferably penetrating a liquid 7 containing component X, which is capable of removing oxide films on the surfaces of conductive particles, into the embedded pattern (pattern 30B). While FIG. 5G shows an embodiment in which a liquid 70 containing component X is dropped or sprayed onto the embedded pattern (pattern 30B), the embedded pattern (pattern 30B) may also be immersed in the liquid containing component X. Alternatively, the liquid 70 containing component X may be brought into contact with the embedded pattern (pattern 30B) using an inkjet method or a dispenser method. The liquid 70 containing component X is preferably water in which component X is dissolved or dispersed. The use of water is preferable from the viewpoints of reducing the environmental load and process safety (non-flammability). Of course, an organic solvent in which component X is dissolved or dispersed can also be used. Instead of using the liquid 70 containing the component X, the oxide film removal step may be carried out by bringing the component X in a gaseous state into contact with the embedded pattern (pattern 30B). It is also possible to bring a sheet containing component X into contact with the embedded pattern (pattern 30B) and, preferably, apply pressure to cause component X to penetrate into the embedded pattern (pattern 30B). Specific examples of the sheet include paper or nonwoven fabric containing component X, and resin sheets having component X coated or printed on their surfaces. Additionally, the method for bringing component X into contact with and permeating the embedded pattern (pattern 30B) is not particularly limited.

[0126] The specific compound of component X and the concentration when the liquid in which component X is dissolved or dispersed is brought into contact with the pattern can be the same as those described in [Example 1], and therefore will not be described again.

[0127] (Pressing process: Figure 5H) In the pressing step, at least pressure is applied to the embedded pattern (pattern 30B). This increases the conductivity of the embedded pattern (pattern 30B) to obtain the conductive pattern 30C. Preferably, the pressing step sinters the conductive particles in the embedded pattern (pattern 30B).

[0128] As shown in FIG. 5H, the pressure is preferably applied by covering the exposed surface of the embedded pattern (pattern 30B) with member 90 and then at least pressurizing the embedded pattern (pattern 30B). As an example, the pressure can be applied by sandwiching a laminate of the substrate 10, cured resin layer 20B, embedded pattern (pattern 30B), and member 90 between two opposing rolls 140A and 140B and transporting the laminate between the two rolls. The member 90 is preferably a film-like material. Incidentally, in Fig. 5H, liquid 70 containing component X, which can remove the oxide film on the surface of the conductive particles as described in Fig. 5G, is present above the embedded pattern (pattern 30B). In this case, it is thought that component X penetrates into the embedded pattern (pattern 30B) by applying pressure, removing the oxide film from the conductive particles while simultaneously sintering the conductive particles. In other words, Fig. 5H can be said to represent an embodiment in which the oxide film removal process and the pressing process are performed simultaneously.

[0129] From one viewpoint, the material of the member 90 can be the same as that of the substrate 10. That is, the member 90 can be preferably a polyester film such as a PET film. From another perspective, in order to prevent peeling or damage to the embedded pattern (pattern 30B), an easily peelable film or release paper can be preferably used as the member 90. A specific example of the easily peelable film or release paper is the easily peelable substrate 50 mentioned in FIG. From another perspective, the member 90 may be made of a non-resin material such as aluminum foil.

[0130] On the other hand, in order to simplify the manufacturing process and reduce waste by reducing the amount of process materials, pressurization may be performed without using the member 90. Furthermore, when the member 90 is used, it may be used only once or may be used repeatedly.

[0131] In the pressing step, it is preferable to apply pressure to the embedded pattern (pattern 30B) while heating it. This tends to improve the conductivity of the conductive pattern 30C. Preferably, the embedded pattern (pattern 30B) is pressed at a pressure of 50 to 300 MPa and heated at a temperature of 80 to 150°C. Incidentally, when the oxide film removal step and the pressing step are performed simultaneously, the heating temperature is preferably set in consideration of the volatilization or evaporation of the liquid 70 and the component X. The lower limit of the temperature, "80°C," described above is a value that takes into consideration the moderate rate of evaporation when the liquid 7 is a mixture of water and a low-boiling point alcohol, etc. When the pressing step is performed using two opposing rolls 140A and 140B as shown in FIG. 5H, it is preferable to use rolls with built-in heaters that can adjust the temperature.

[0132] (Other optional steps: Figure 5I, etc.) The manufacturing method of Example 2 may include steps other than those described above. For example, if the member 90 is used in the pressing step, the member 90 is removed after the pressing step is completed (FIG. 5I). As another example, after the pressing step, a removal step may be performed to remove component X remaining on the surface or inside of the obtained conductive pattern. Specific examples include a step of immersing the substrate provided with the obtained conductive pattern in a liquid (water or an organic solvent) capable of dissolving or dispersing component X, or a step of washing away the remaining component X by pouring a liquid (water or an organic solvent) onto the surface of the conductive pattern. Another possible step is to vaporize the remaining component X by heating the substrate provided with the obtained conductive pattern at a temperature that does not damage the substrate 10.

[0133] <Electronic Devices> An electronic device can be manufactured using a substrate having the conductive pattern of this embodiment. By appropriately designing the conductive pattern, a substrate having a conductive pattern (circuit pattern) that can function as a circuit can be manufactured. Then, by combining this substrate with other electronic elements, an electronic device can be manufactured.

[0134] Here, some examples of electronic devices are described, but it should be noted that the electronic devices are of course not limited to these. Sensors: For example, the substrate provided with the conductive pattern of this embodiment can be applied to conductive members / circuits in sensors such as pressure sensors and vital sensors. Solar cells: For example, the substrate provided with the conductive pattern of this embodiment can be applied to the current collecting wiring of solar cells. Membrane switch: A membrane switch is a thin sheet-like switch made by printing circuits and contacts on a film and then laminating it. The substrate with the conductive pattern of this embodiment can be used to form these circuits and contacts. Touch sensor / touch panel: For example, a substrate having the conductive pattern of this embodiment can be applied to form lead wiring in a touch sensor / touch panel. Also, the manufacturing method of a substrate having the conductive pattern of this embodiment can be applied to form transparent electrodes in a touch sensor / touch panel. Flexible substrate: Conventionally, a circuit is formed by first coating the entire surface of a flexible film with a metal film and then removing unnecessary parts of the metal film using chemicals. Instead of this conventional method, it is possible to form a circuit using the manufacturing method of a substrate with a conductive pattern of this embodiment.

[0135] In particular, in electronic devices where circuits have conventionally been formed using conductive paste, by using the manufacturing method of this embodiment to form circuits, the resistivity of the circuits can be reduced, and improved performance of the electronic devices can be expected.

[0136] A particularly preferred electronic device is an RF tag, in which the substrate having the conductive pattern of this embodiment is preferably used to manufacture a conductive circuit such as an antenna portion in an RF tag. For the specific structure of the RF tag, reference can be made to, for example, Japanese Patent Application Laid-Open No. 2003-332714 and Japanese Patent Application Laid-Open No. 2020-46834.

[0137] <Method of manufacturing electromagnetic wave shielding film> As an application other than electronic devices, the method for manufacturing a substrate having a conductive pattern according to the present embodiment can be used to manufacture an electromagnetic wave shielding film. Specifically, in the lamination step, the conductive composition is printed in a pattern specific to the electromagnetic wave shielding film (such as a mesh pattern), thereby manufacturing the electromagnetic wave shielding film.

[0138] <Method of manufacturing a sheet heating element> As another application, the method for manufacturing a substrate having a conductive pattern according to this embodiment may be used to manufacture a sheet heating element. A sheet heating element is an element that generates heat by passing an electric current through electrical wiring provided on a substrate. A specific example of a sheet heating element is a sheet heating element for preventing fogging or cold weather, such as on the rear window of a passenger car.

[0139] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations may be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention. [Example]

[0140] The embodiments of the present invention will be described in detail based on Examples and Comparative Examples. However, it should be noted that the present invention is not limited to the Examples. In the following, exponential notation may be indicated by the symbol "E." For example, 1.3E-06 is 1.3 x 10 -6 means.

[0141] <Production of a substrate with a conductive pattern by the production method of [Example 1]> (Production of conductive resin composition) Manufacturing example 1 (without resin components) Fukuda Metal Foil and Powder Co., Ltd.'s D 50 77.0 parts by mass of copper powder with a particle size of 5 μm and 23.0 parts by mass of an organic solvent were weighed and kneaded with a spatula to obtain a kneaded mixture, which was then stirred using a planetary centrifugal mixer. In this way, a conductive composition was obtained for Production Example 1. This composition was in a paste state at 23°C.

[0142] Manufacturing example 2 (contains resin components) 15 parts by mass of commercially available phenoxy resin and 85 parts by mass of organic solvent were weighed into a glass bottle, placed in a hot air circulating atmospheric oven, and heated at 120°C for 6 hours to completely dissolve the resin, thereby preparing a 15% by mass solution of phenoxy resin. Fukuda Metal Foil and Powder Co., Ltd.'s D 50 75.3 parts by mass of copper powder with a particle size of 5 μm, 12.9 parts by mass of the 15% by mass solution of the phenoxy resin, and 11.9 parts by mass of an organic solvent were weighed and kneaded with a spatula, and then stirred using a planetary centrifugal mixer. In this way, a conductive composition of formulation 2 was obtained. This composition was in a paste state at 23°C.

[0143] (Example I-1: Production of a substrate with a conductive pattern, an example using a paper substrate) A substrate having a conductive pattern was manufactured by the following process. (i) Formation of a temporary pattern on the surface of an easily peelable substrate: corresponding to Figure 2P1 and Figure 2P2 (ii) Formation of an adhesive layer on the substrate: Corresponding to Figure 2A (iii) Transfer step: corresponds to Figure 3B (iv) Adhesive layer curing process: equivalent to Figure 3C (v) Pressing before oxide film removal process: not shown (vi) Peeling process: corresponds to Figure 3D (vii) Oxide film removal process and pressing process: corresponding to Figure 3E and Figure 3F

[0144] Each process will be described in detail below.

[0145] (i) Formation of a temporary pattern on the surface of an easily peelable substrate: corresponding to Figure 2P1 and Figure 2P2 The conductive composition of Production Example 1 (containing no resin component) was screen-printed onto an easily peelable substrate to form a provisional pattern under the following specific conditions. -Easy-to-peel substrate: Fujimori Kogyo Co., Ltd. uses a PET film with a silicone resin surface coating. Printing machine: A screen printing machine, Desk Top 38SA type (Micro-Tec) was used. Screen: 325 mesh, wire diameter 16 μm, emulsion thickness 28 μm. Printing conditions: printing pressure 0.18 MPa, squeegee speed 30 mm / sec, clearance (distance between screen and substrate) 2.0 mm, attack angle 80°. Overall shape of the pattern: The antenna pattern was as shown in Figure 6. In this pattern, the width of the thin line portion was 200 μm.

[0146] The easily peelable substrate after screen printing was placed in a hot air circulating atmospheric oven and heated at 100°C for 15 minutes, thereby volatilizing the solvent. In this manner, a provisional pattern having a height of 50 μm was formed on the surface of the easily peelable substrate.

[0147] (ii) Formation of an adhesive layer on the substrate: Corresponding to Figure 2A To prevent curling, double-sided coated paper, Mirror Coat Platinum (180 μm thick, manufactured by Oji Paper Co., Ltd.), was selected as the substrate. Furthermore, the adhesive layer was made to have a two-layer structure, taking into consideration penetration into the paper. The specific procedure for forming the adhesive layer was as follows: First, a mixture of epoxy resin YX7200B35 (Mitsubishi Chemical Corporation) and the solvent tetrahydrofuran was prepared in a mass ratio of 1:1. This mixture was applied to the surface of the substrate using a bar coater to a wet thickness of 30 μm. The substrate was then placed in a hot air circulating atmospheric oven and heated at 100°C for 15 minutes. This volatilized the solvent, forming the first adhesive layer. Next, a UV hard coating agent, HX-RSC (Kyoeisha Chemical Co., Ltd., urethane acrylate material), was applied to the first adhesive layer using a bar coater to a wet thickness of 15 μm. The substrate was then placed in a hot air circulating atmospheric oven and heated at 80°C for 5 minutes. This volatilized the solvent, forming a second adhesive layer (dry thickness 6 μm). In this manner, a substrate provided with an adhesive layer was obtained.

[0148] (iii) Transfer step: corresponds to Figure 3B The substrate with the adhesive layer formed in step (ii) was placed on top of the provisional pattern obtained in step (i) so that the provisional pattern and the adhesive layer were in contact with each other. Then, a 2 kg roller was used to apply pressure. This transferred the provisional pattern to the adhesive layer, forming a transfer pattern.

[0149] (iv) Adhesive layer curing process: equivalent to Figure 3C After the above (iii) is completed, the adhesive layer to which the transfer pattern has been transferred is irradiated with UV-LED irradiation equipment (Matsuo Sangyo Co., Ltd.) that emits ultraviolet light with a wavelength of 365 nm, with an integrated light dose of UVA: 6000 mJ / cm 2The adhesive layer was cured by ultraviolet light of 1000 W at 1000 W from the side of the easily peelable substrate, thereby forming a cured adhesive layer.

[0150] (v) Pressing before oxide film removal process After the above (iv) was completed, the laminate including the substrate, the cured adhesive layer, the transfer pattern, and the easily peelable substrate was roll-pressed under the following conditions using a load-adjustable roll press machine SA-602 (Tester Sangyo Co., Ltd.) equipped with two opposing rolls. Roll temperature: 110°C, pressure: 20 MPa, conveying speed: 0.1 m / min, gap: 90-100 μm *Note 1: Regarding the roll temperature, although the roll press machine is equipped with a non-contact temperature sensor, a contact thermometer was used to measure the temperature more accurately. *Note 2: Pressure was calculated using the following formula: Roll width: 165 mm, contact width between rolls: 3 mm, pressure area: 495 mm 2 The pressure was set to 10kN. 2 Since a force of 10kN was applied to the area, 10kN ÷ 495mm 2 Based on the calculation, the pressure was calculated to be 20 MPa.

[0151] (vi) Peeling process: corresponds to Figure 3D After the above (v) was completed, the easily peelable substrate was peeled off by hand.

[0152] (vii) Oxide film removal process and pressing process: corresponding to Figure 3E and Figure 3F An oxide film removal solution (formic acid aqueous solution) was sprayed onto the pattern (transfer pattern) after (vi) above. The amount sprayed was approximately 20 μL for an area of ​​approximately 30 mm × 20 mm on the substrate. A film-like member (the same as the easily peelable substrate on which the provisional pattern was formed, manufactured by Fujimori Kogyo Co., Ltd.) was then placed on top of it. In this state, a roll press treatment was performed using a load-adjustable roll press machine SA-602 (Tester Sangyo Co., Ltd.) equipped with two opposing rolls. The treatment conditions were as follows: Roll temperature: 110°C, pressure: 40 MPa, conveying speed: 0.1 m / min, gap: 40-50 μm ※remarks The roll temperature and pressure were determined in the same manner as in Notes 1 and 2 of (v) Pressing before the oxide film removal step.

[0153] In this manner, the pattern (transfer pattern) was pressed while the oxide film remover solution was allowed to penetrate into the gaps between the conductive particles in the pattern (transfer pattern), thereby obtaining a conductive pattern.

[0154] Through the above series of steps, a substrate with a conductive pattern was obtained, in which a conductive antenna pattern was formed on the paper substrate via a cured adhesive layer. As will be explained in more detail later with reference to electron microscope images, in the cross section of the obtained conductive pattern, in the part where the conductive pattern was thickest, the conductive particles were densely compressed in areas away from the substrate, but the conductive particles were not so compressed in areas closer to the substrate.

[0155] (Example II-1: Production of a substrate with a conductive pattern, an example using a PET substrate) A substrate having a conductive pattern was manufactured by the following process. (i) Formation of a temporary pattern on the surface of an easily peelable substrate: corresponding to Figure 2P1 and Figure 2P2 (ii) Formation of an adhesive layer on the substrate: Corresponding to Figure 2A (iii) Transfer step: corresponds to Figure 3B (iv) Adhesive layer curing process: equivalent to Figure 3C (v) Pressing before oxide film removal process: not shown (vi) Peeling process: corresponds to Figure 3D (vii) Oxide film removal process and pressing process: corresponding to Figure 3E and Figure 3F

[0156] Each process will be described in detail below.

[0157] (i) Formation of a temporary pattern on the surface of an easily peelable substrate: corresponding to Figure 2P1 and Figure 2P2 A temporary pattern was formed on the surface of an easily peelable substrate in the same manner as in (i) of Example I-1, except that the conductive composition of Production Example 2 (with resin component) was used instead of Production Example 1 (without resin component).

[0158] (ii) Formation of an adhesive layer on the substrate: Corresponding to Figure 2A The substrate was selected to be a PET film, Lumirror U34 (75 μm thick), manufactured by Toray Industries, Inc. Unlike the paper substrate used in Example I-1, the components constituting the adhesive layer do not substantially penetrate the PET film, so the adhesive layer was a single layer. Specifically, a UV hard coating agent, HX-RSC (Kyoeisha Chemical Co., Ltd., urethane acrylate-based material), was applied to the surface of the PET film using a bar coater to a wet thickness of 30 μm. The substrate was then placed in a hot air circulating atmospheric oven and heated at 80°C for 15 minutes. This volatilized the solvent, forming an adhesive layer (dry thickness 4 μm). In this manner, a substrate provided with an adhesive layer was obtained.

[0159] (iii) Transfer step: corresponds to Figure 3B The temporary pattern was transferred to the adhesive layer side in the same manner as in Example I-1(iii).

[0160] (iv) Adhesive layer curing process: equivalent to Figure 3C The adhesive layer was cured to form a cured adhesive layer in the same manner as in (iv) of Example I-1.

[0161] (v) Pressing before oxide film removal process Roll pressing was carried out in the same manner as in Example I-1 (v).

[0162] (vi) Peeling process: corresponds to Figure 3D The easily peelable substrate was peeled off in the same manner as in (vi) of Example I-1.

[0163] (vii) Oxide film removal process and pressing process: corresponding to Figure 3E and Figure 3F The oxide film removing step and the pressing step were carried out in the same manner as in (vii) of Example I-1.

[0164] Through the above series of steps, a substrate with a conductive pattern was obtained, in which a conductive antenna pattern was formed on the PET substrate via a cured adhesive layer. As will be explained in more detail later with reference to electron microscope images, in the cross section of the obtained conductive pattern, in the part where the conductive pattern was thickest, the conductive particles were densely compressed in areas away from the substrate, but the conductive particles were not so compressed in areas closer to the substrate.

[0165] <Production of a substrate with a conductive pattern by the production method of [Example 2]> (Production of conductive composition) 15% by mass of commercially available phenoxy resin and 85 parts by mass of organic solvent were weighed and placed in a glass bottle. The glass bottle was placed in a hot air circulating oven and heated at 120°C for 6 hours. This allowed the resin to completely dissolve. A 15% by mass solution of phenoxy resin was then prepared. Fukuda Metal Foil and Powder Co., Ltd.'s D 50 82 parts by mass of copper powder with a particle size of 5 μm and 18 parts by mass of the 15% by mass solution of the phenoxy resin were weighed and kneaded with a spatula. Then, the mixture was stirred using a planetary stirrer. In this way, a conductive composition was obtained. The ratio of resin to copper powder in the obtained conductive composition was 3.4% by mass.

[0166] (Example III-1: Production of a substrate with a conductive pattern) A substrate having a conductive pattern was manufactured by the following process. (i) Formation of a temporary pattern on the surface of an easily peelable substrate: corresponding to Figure 4P1 and Figure 4P2 (ii) Formation of a resin-containing layer on a substrate: corresponds to Figures 4A to 4C (iii) Embedding process: corresponds to Figure 5D (iv) Curing step (curing of the resin-containing layer): corresponds to Figure 5E (v) Peeling process: corresponds to Figure 5F (vi) Oxide film removal process and pressing process: corresponding to Figure 5G and Figure 5H (vii) Removal of the member (film-like material): corresponds to Figure 5I

[0167] Each process will be described in detail below. Here, we will provide additional information regarding the temperature and pressure when roll pressing is performed in the following process. Roll temperature Although the roll press machine is equipped with a non-contact temperature sensor, the roll temperature was measured by attaching a contact thermometer to the roll itself to obtain more accurate temperature measurements. Pressure during roll pressing The pressure during roll pressing was calculated by the following calculation. Roll width: 165 mm, contact width between rolls: 3 mm, pressure area: 495 mm 2 This 495mm 2 When a force F is applied to the area, F ÷ 495 mm 2 The pressure was calculated by the following calculation.

[0168] (i) Formation of a temporary pattern on the surface of an easily peelable substrate: corresponding to Figure 4P1 and Figure 4P2 The conductive composition, the manufacturing method of which is explained in the above section (Manufacturing of Conductive Composition), was screen-printed onto an easily peelable substrate to form a provisional pattern on the surface of the easily peelable substrate. The specific conditions were as follows: -Easy-to-peel substrate: PET film with a silicone resin surface coating, manufactured by Fujimori Kogyo Co., Ltd. Printing machine: A screen printing machine, Desk Top 38SA type (Micro-Tec) was used. Screen: 325 mesh, wire diameter 16 μm, emulsion thickness 28 μm. Printing conditions: printing pressure 0.18 MPa, squeegee speed 30 mm / sec, clearance (distance between screen and substrate) 2.0 mm, attack angle 80°. Overall shape of the pattern: Same as in Example I-2 (antenna pattern shown in Figure 6, width of thin line part is 200 μm)

[0169] The easily peelable substrate after screen printing was placed in a hot air circulating atmospheric oven and heated at 100°C for 15 minutes, thereby volatilizing the solvent. In this manner, a provisional pattern having a height of 50 μm was formed on the surface of the easily peelable substrate.

[0170] (ii) Formation of a resin-containing layer on a substrate: corresponds to Figures 4A to 4C A commercially available 15 μm thick thermosetting OCA film was laminated to one side of a polyethylene terephthalate (PET) film "Cosmoshine A4360" (188 μm thick) manufactured by Toyobo Co., Ltd. This resulted in a laminate in which a 15 μm thick resin-containing layer was formed on one side of the PET film. The specific lamination method was roll pressing using two opposing rolls using a load-adjustable roll press machine SA-602 (Tester Sangyo Co., Ltd.) under the following conditions: Roll temperature: 80°C, pressure: 2 MPa, conveying speed: 0.1 m / min, gap: 225-235 μm

[0171] (iii) Embedding process: corresponds to Figure 5D The provisional pattern obtained in (i) above was embedded in the resin-containing layer obtained in (ii) above. Specifically, the provisional pattern obtained in (i) above was pressed together with the easily peelable substrate against the resin-containing layer side of the PET film-resin-containing layer laminate obtained in (ii) above. More specifically, the laminated structure (overlapping structure) shown in FIG. 5D was subjected to roll pressing with two opposing rolls using a load-adjustable roll press machine SA-602 (Tester Sangyo Co., Ltd.) under the following conditions: Roll temperature: 80°C, pressure: 2 MPa, conveying speed: 0.1 m / min, gap: 245 to 255 μm

[0172] Incidentally, in the case of the OCA film used to form the resin-containing layer, it is thought that the roll pressing at 80°C as described above softened the resin-containing layer more than at room temperature, making it easier to embed the temporary pattern.

[0173] (iv) Curing step (curing of the resin-containing layer): corresponds to Figure 5E After the above step (iii) was completed, the entire laminated structure (overlapping structure) was placed in a hot air circulating atmospheric oven and heated at 120°C for 15 minutes, thereby curing the resin-containing layer (OCA film) to form a cured resin layer.

[0174] (v) Peeling process: corresponds to Figure 5F After the above (iv) was completed, the easily peelable substrate was peeled off by hand.

[0175] (vi) Oxide film removal process and pressing process: corresponding to Figure 5G and Figure 5H An oxide film removal solution (formic acid solution) was sprayed onto the pattern (embedded pattern) after (v) above. The amount sprayed was approximately 20 μL for an area of ​​approximately 30 mm × 20 mm on the substrate. A film-like member (the same as the easily peelable substrate on which the provisional pattern was formed, manufactured by Fujimori Kogyo Co., Ltd.) was then placed on top of it. In this state, a roll press treatment was performed using a load-adjustable roll press machine SA-602 (Tester Sangyo Co., Ltd.) equipped with two opposing rolls. The treatment conditions were as follows: Roll temperature: 110°C, pressure: 20 MPa, conveying speed: 0.1 m / min, gap: 165-175 μm

[0176] (vii) Removal of the member (film-like material): corresponds to Figure 5I After the treatment (vi) and cooling, the film-like member (manufactured by Fujimori Kogyo Co., Ltd.) was removed.

[0177] Through the above series of steps, a substrate with a conductive pattern was obtained, in which a conductive antenna pattern was formed on the PET substrate via a cured adhesive layer. As will be explained in more detail later with reference to electron microscope images, in the cross section of the obtained conductive pattern, in the part where the conductive pattern was thickest, the conductive particles were densely compressed in areas away from the substrate, but the conductive particles were not so compressed in areas closer to the substrate.

[0178] (Example IV-1: Production of a substrate with a conductive pattern) In "(ii) Formation of a resin-containing layer on a substrate: corresponding to Figures 4A to 4C", a substrate having a conductive pattern was produced in the same manner as in Example III-1, except that two OCA films, instead of one, were stacked and attached to a polyethylene terephthalate (PET) film to obtain a laminate in which a 30 μm-thick resin-containing layer was formed on one side of the PET film.

[0179] As will be explained in more detail later with reference to electron microscope images, in the cross section of the obtained conductive pattern, in the part where the conductive pattern was thickest, the conductive particles were densely compressed in areas away from the substrate, but the conductive particles were not so compressed in areas closer to the substrate.

[0180] <Photographing the pattern cross section and calculating ε0, ε1, ε0' and ε1'> The substrate having the obtained conductive pattern was cut to expose a cross section of the linear portion of the conductive pattern in a direction perpendicular to the direction in which the conductive pattern extended, and this cross section was then photographed using an electron microscope. The cross-sectional images of the photographed patterns were analyzed using software to calculate ε0, ε1, etc. Specifically, the software ImageJ, version 1.54h, was used to first convert the cross-sectional images to grayscale (8-bit). After that, binarization processing was performed to calculate ε0, ε1, etc. The threshold setting in the binarization processing was generally set to the default Auto setting, and the threshold was fine-tuned only when the results of the binarization processing were clearly different from what was seen.

[0181] Figure 7 shows a cross-sectional image of a substrate having a conductive pattern obtained in Example I-1 and the calculation results of ε0, ε1, ε0' and ε1'; Figure 8 shows a cross-sectional image of a substrate having a conductive pattern obtained in Example II-1 and the calculation results of ε0, ε1, ε0' and ε1'; Figure 9 shows a cross-sectional image of a substrate having a conductive pattern obtained in Example III-1 and the calculation results of ε0, ε1, ε0' and ε1'; and Figure 10 shows a cross-sectional image of a substrate having a conductive pattern obtained in Example IV-1 and the calculation results of ε0, ε1, ε0' and ε1'.

[0182] <Evaluation> (resistance value) In the pattern obtained in each example and having the shape shown in Fig. 6, the resistance value between points 1 and 2 and the resistance value between points 3 and 4 were measured. The smaller of the two measured resistance values ​​is listed in the table below.

[0183] (adhesion) The substrates provided with the conductive patterns obtained in each example were each bent by hand and returned to their original flat shape, and this operation was repeated five times. The presence or absence of peeling of the conductive pattern was then confirmed visually and under magnification. The case where no peeling of the conductive pattern was observed was evaluated as good, and the case where peeling of the conductive pattern was observed was evaluated as bad.

[0184] The various information is summarized in the table below.

[0185] [Table 1]

[0186] The resistance values ​​shown in Table 1 were all at a level that allowed the obtained antenna patterns to be used as antennas in RF tags. In other words, it was unexpectedly found that good conductivity can be obtained even when the entire conductive pattern is not densified, but only a portion of the conductive pattern is densified. Furthermore, the conductive patterns had good adhesion to the substrates obtained in Examples 1 to 4. This is presumably because the curable resin component penetrated into some of the gaps in the conductive patterns and cured. [Explanation of symbols]

[0187] 1 Base material 2 Adhesive layer 2B Cured adhesive layer 3 patterns 3B provisional pattern 3C Conductive Pattern 5. Easy-to-peel substrate 6. Member (preferably film-like material) 7. A liquid containing component X capable of removing oxide films on the surfaces of conductive particles 10A roll 10B roll 10 Base material 20 Resin-containing layer 20B Cured resin layer 30 patterns 30B Pattern (provisional pattern, embedded pattern) 30C Conductive Pattern 50 Easy-to-peel substrate 60 Peel-off sheet 70 Liquid (liquid containing component X capable of removing oxide film on the surface of conductive particles) 90 member (preferably film-like material) 100A roll 100B roll 120A roll 120B roll 140A roll 140B roll

Claims

1. A substrate with a conductive pattern, comprising: a substrate; and a conductive pattern including a plurality of conductive particles provided on one surface side of the substrate, In the cross section of the conductive pattern, in the part where the thickness of the conductive pattern is the greatest, a square region S of 8 μm on each side is formed as close as possible to the substrate. ０ A square area S of 8 μm on each side is placed as far away as possible from the substrate. １ Set The square area S ０ The area ratio of the area where conductive particles exist is ε ０ and the square area S １ The area ratio of the area where conductive particles exist is ε １ When ε １ is 65% or more, and ε ０ <ε １ A substrate having a conductive pattern.

2. A substrate provided with the conductive pattern according to claim 1, The ε ０ A substrate having a conductive pattern, wherein the surface roughness is less than 45%.

3. A substrate provided with the conductive pattern according to claim 1, The ε ０ A substrate having a conductive pattern, wherein the conductive property is greater than 60%.

4. A substrate provided with the conductive pattern according to any one of claims 1 to 3, ε １ / ε ０ A substrate provided with a conductive pattern, wherein the value of

5. A substrate provided with the conductive pattern according to any one of claims 1 to 3, The square area S ０ a resin component has permeated at least a part of the area where no conductive particles are present, A substrate having a conductive pattern, wherein when a cross section of the conductive pattern is observed with an electron microscope, two layers are observed: a layer infiltrated with the resin component and a layer not infiltrated with the resin component.

6. A substrate provided with the conductive pattern according to claim 5, A substrate provided with a conductive pattern, wherein the maximum thickness of the layer infiltrated with the resin component is 5 to 50% of the maximum thickness of the conductive pattern.

7. A substrate provided with the conductive pattern according to claim 5, The substrate includes at least a substrate layer and a cured resin layer, a portion of the conductive pattern is in contact with the cured resin layer; The resin component is formed by penetration and hardening of a curable resin material that forms the cured resin layer.

8. A substrate provided with the conductive pattern according to any one of claims 1 to 3, A substrate having a conductive pattern, wherein the resin component does not substantially contain an inorganic filler.

9. A substrate provided with the conductive pattern according to any one of claims 1 to 3, The particle diameter D at which the cumulative frequency reaches 50% in a volume-based cumulative particle diameter distribution curve obtained when the particle diameter of the conductive particles is measured by a laser diffraction scattering method. ５０ A substrate provided with a conductive pattern, wherein the thickness is 0.5 to 100 μm.

10. A substrate provided with the conductive pattern according to any one of claims 1 to 3, The substrate is flexible and has a conductive pattern.

11. A substrate provided with the conductive pattern according to any one of claims 1 to 3, The substrate is provided with a conductive pattern and includes at least one selected from the group consisting of polyester, polyolefin, polycarbonate, polyimide, and paper.

12. An electronic device comprising a substrate provided with the conductive pattern according to any one of claims 1 to 3.

13. 13. The electronic device of claim 12, An RF tag is an electronic device.

14. An electromagnetic wave shielding film comprising a substrate having the conductive pattern according to any one of claims 1 to 3.

15. A sheet heating element comprising a substrate provided with the conductive pattern according to any one of claims 1 to 3.

16. A substrate with a conductive pattern, comprising: a substrate; and a conductive pattern including a plurality of conductive particles provided on one surface side of the substrate, In the cross section of the conductive pattern, in the part where the thickness of the conductive pattern is greatest, a square region S of 5 μm on each side is formed as close as possible to the substrate. ０ ' is placed in a square area S 5 μm square as far away as possible from the substrate. １ ' and set The square area S ０ The area ratio of the area where conductive particles exist in ' is ε ０ ', and the square area S １ The area ratio of the area where conductive particles exist in ' is ε １ ', ε １ ' is 65% or more, and ε ０ '<ε １ 'A substrate having a conductive pattern.

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