TW201708469A - Electroconductive pressure-sensitive adhesive material, and electroconductive pressure-sensitive adhesive material with electroconductive substrate - Google Patents

Abstract

Provided is an electroconductive pressure-sensitive adhesive material which can have a sufficiently heightened electromagnetic-wave-shielding function even when the adherend has a rugged surface. The electroconductive pressure-sensitive adhesive material according to the present invention comprises a plurality of metal particles, a plurality of electroconductive particles, and a pressure-sensitive adhesive component, the electroconductive particles each comprising a base particle which is not a metal particle and an electroconductive part disposed on the surface of the base particle, and the electroconductive particles each having a plurality of projections in the outer surface of the electroconductive part.

Description

Conductive adhesive material and conductive adhesive material with conductive substrate

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a conductive adhesive material, and more particularly to a conductive adhesive material which can be preferably used for shielding electromagnetic waves. Further, the present invention relates to a conductive adhesive material to which a conductive substrate of the above-mentioned conductive adhesive material is attached.

Previously, in electrical or electronic equipment, electromagnetic wave shielding materials were used to protect circuits or electronic component components.

Generally, as an electromagnetic wave shielding material, an adhesive sheet containing metal particles is used. Further, the adhesive sheet may be used by laminating on a conductive substrate.

Further, Patent Document 1 listed below discloses a case where a conductive resin composition containing conductive particles and a resin is used as an electromagnetic wave shielding material. In Patent Document 1, the conductive particles include a core body including a conductive material and a coating layer covering the core body. The coating layer is formed of a conductive material different from the core body, and at least a part of the coating layer constitutes the outermost layer.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] WO2013/132831A1

The electromagnetic wave shielding material of the prior art of Patent Document 1 may not sufficiently exhibit the electromagnetic wave shielding function. Especially for the surface of the adherend to which the electromagnetic wave shielding material is applied. When there is unevenness, there is a problem that the electromagnetic wave shielding function is liable to become low.

An object of the present invention is to provide a conductive adhesive material which can sufficiently improve the electromagnetic wave shielding function even if the surface of the adherend has irregularities. Further, an object of the present invention is to provide a conductive adhesive material with a conductive substrate to which the above-mentioned conductive adhesive material is used.

According to a broad aspect of the present invention, a conductive adhesive material comprising a plurality of metal particles, a plurality of conductive particles, and an adhesive component, wherein the conductive particles are provided with a substrate particle not containing metal particles And conductive particles disposed on the conductive portion on the surface of the substrate particle, wherein the conductive particles have a plurality of protrusions on the outer surface of the conductive portion.

In one aspect of the conductive adhesive material of the present invention, the conductive particles are contained in an amount of 1% by weight or more and 30% by weight or less based on 100% by weight of the conductive adhesive.

In one aspect of the conductive adhesive material of the present invention, the conductive particles have a particle diameter of 3 μm or more and 40 μm or less.

In a specific aspect of the conductive adhesive material of the present invention, the conductive particles have a volume resistivity of 0.001 Ω‧ cm or less.

In a specific aspect of the conductive adhesive material of the present invention, the ratio of the particle diameter of the conductive particles to the particle diameter of the metal particles is 0.7 or more and 5,000 or less.

In one aspect of the conductive adhesive material of the present invention, the average height of the protrusions is 30 nm or more and 1000 nm or less.

In one aspect of the conductive adhesive of the present invention, in the 100% of the total surface area of the outer surface of the conductive portion, the surface area of the portion where the protrusion is located is 0.1% or more.

In a specific aspect of the conductive adhesive material of the present invention, the conductive particles are A plurality of core materials are provided which emboss the outer surface of the conductive portion.

In a specific aspect of the conductive adhesive material of the present invention, the material of the core material has a Mohs hardness of 5 or more.

In a specific aspect of the conductive adhesive material of the present invention, the conductive adhesive material has a thickness of 5 μm or more and 40 μm or less.

According to a broad aspect of the present invention, a conductive adhesive material having a conductive substrate, comprising the conductive adhesive material and a conductive substrate, and the conductive adhesive material disposed on the conductive base On the surface of the material.

In one aspect of the conductive adhesive material with a conductive substrate of the present invention, the conductive substrate is a copper foil.

The conductive adhesive material of the present invention comprises a plurality of metal particles, a plurality of conductive particles, and an adhesive component, and the conductive particles are provided with substrate particles not including metal particles, and are disposed on a surface of the substrate particles. In the conductive particles of the conductive portion, the conductive particles have a plurality of protrusions on the outer surface of the conductive portion. Therefore, even if the surface of the adherend has irregularities, the electromagnetic wave shielding function can be sufficiently improved.

1, 1A, 1B, 1C‧‧‧ conductive particles

2‧‧‧Substrate particles

3, 3A, 3B, 3C‧‧‧Electrical Department

3a, 3Aa, 3Ba, 3Ca‧‧‧ protrusion

3BA, 3CA‧‧‧1st Conductive Department

3CAa‧‧‧ Protrusion

3BB, 3CB‧‧‧2nd Conductive Department

3BBa, 3CBa‧‧‧ Protrusion

4‧‧‧ core material

51‧‧‧ Conductive adhesive materials with conductive substrates

52‧‧‧ Conductive adhesive materials

53‧‧‧Electrically conductive substrate

56‧‧‧Metal particles

57‧‧‧Adhesive ingredients

61‧‧‧ Conductive adhesive materials with conductive substrates

62‧‧‧ Lower pure copper electrode

63‧‧‧Upper pure copper electrode

Fig. 1 is a cross-sectional view showing a conductive adhesive material with a conductive substrate according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view showing conductive particles used in a conductive adhesive material with a conductive substrate according to an embodiment of the present invention.

Fig. 3 is a cross-sectional view showing a first modification of the conductive particles.

Fig. 4 is a cross-sectional view showing a second modification of the conductive particles.

Fig. 5 is a cross-sectional view showing a third modification of the conductive particles.

Fig. 6 is a view for explaining a method of evaluating the connection resistance.

Hereinafter, the present invention will be described in detail.

The conductive adhesive material of the present invention is particularly preferably used for shielding electromagnetic waves. The conductive adhesive material of the present invention is particularly preferably used as an electromagnetic wave shielding material. The conductive adhesive material of the present invention has an electromagnetic wave shielding function. Further, the conductive adhesive material of the present invention can be disposed on the surface of the heat-generating component or can be used as a heat-dissipating member.

The conductive adhesive material of the present invention is an adhesive layer. The conductive adhesive material of the present invention can be preferably used for obtaining a conductive adhesive material having a conductive substrate to which the conductive adhesive (adhesive layer) and the conductive substrate are provided. The conductive adhesive (adhesive layer) may be disposed on the surface of the conductive substrate.

The conductive adhesive material of the present invention comprises a plurality of metal particles, a plurality of conductive particles, and an adhesive component.

In the conductive adhesive material of the present invention, the conductive particles are provided with substrate particles that do not contain metal particles, and conductive particles that are disposed on the surface of the substrate particles.

In the conductive adhesive material of the present invention, the conductive particles have a plurality of protrusions on the outer surface of the conductive portion.

Since the conductive adhesive material of the present invention has the above configuration, the electromagnetic wave shielding function can be sufficiently improved even if the surface of the adherend has irregularities. In particular, the metal particles and the conductive particles are used in combination, and conductive particles including a substrate particle not including metal particles and a conductive portion disposed on a surface of the substrate particle are used as the conductive particles and further conductive The combination of the constituents having the protrusions on the outer surface of the conductive portion greatly contributes to the improvement of the electromagnetic wave shielding function when the electromagnetic wave shielding material is applied to the uneven surface. Further, in particular, since the conductive particles have protrusions on the outer surface of the conductive portion, the conductive adhesive can be satisfactorily followed by the uneven surface. As a result, the electromagnetic wave shielding function becomes high.

Further, the conductive adhesive material of the present invention is applied at the time of formation of a conductive adhesive material Good sex. In the above-mentioned conductive adhesive material, the dispersibility of the conductive particles is good, and the distribution of the adhesive components in the application region is particularly uniform, and the unevenness of the adhesive strength can be reduced. Since the conductive adhesive material of the present invention has the above-described configuration, it is less likely to cause breakage of the conduction path due to displacement of the adhesive portion due to heat or impact, and thus the durability and heat resistance of electromagnetic wave shielding can be sufficiently improved. Moreover, since the conductive adhesive material of the present invention has the above configuration, it is possible to sufficiently improve the heat dissipation property when disposed on the surface of the heat generating component. The conductive adhesive material of the present invention is excellent in adhesion, connection resistance, electromagnetic wave shielding property, and electromagnetic wave shielding durability.

In order to effectively improve the electromagnetic wave shielding function, the conductive adhesive material of the present invention preferably has a content of the conductive particles of 1% by weight or more and 30% by weight or less.

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described more specifically by reference to the embodiments of the invention.

Fig. 1 is a cross-sectional view showing a conductive adhesive material with a conductive substrate according to an embodiment of the present invention. The conductive adhesive material with a conductive substrate is provided with a conductive adhesive.

The conductive adhesive material 51 with a conductive substrate shown in FIG. 1 has a conductive adhesive material 52 and a conductive base material 53. The conductive adhesive material 52 is disposed on the surface of the conductive substrate 53. The conductive adhesive material 52 includes a plurality of metal particles 56, a plurality of conductive particles 1, and an adhesive component 57.

In the following, the conductive base material, the conductive adhesive material, the metal particles contained in the conductive adhesive material, the conductive particles contained in the conductive adhesive material, and the adhesive component contained in the conductive adhesive material are more specifically described. Description.

(conductive substrate)

The conductive adhesive material of the present invention can be placed on a conductive substrate as described above, and can be formed into a conductive adhesive sheet or a conductive adhesive tape. Examples of the conductive substrate include metal substrates such as metal foils, metal meshes, and metal plates. Examples of the material of the conductive substrate include copper, aluminum, and the like. Examples of the metal foil include copper foil and aluminum foil. Wait.

The conductive substrate is preferably a metal substrate, more preferably a metal foil, a metal mesh or a metal plate, and more preferably a metal foil, from the viewpoint of effectively improving the electromagnetic wave shielding function. The material of the above conductive substrate is preferably copper or aluminum, more preferably copper. The conductive substrate is more preferably a copper foil or an aluminum foil, and further preferably a copper foil.

The thickness of the conductive substrate is preferably 5 μm or more, more preferably 10 μm or more, more preferably 40 μm or less, still more preferably 30 μm or less, and still more preferably 20 μm or less from the viewpoint of effectively improving the electromagnetic wave shielding function.

(conductive adhesive material)

The thickness of the conductive adhesive material is preferably 5 μm or more, more preferably 10 μm or more, more preferably 40 μm or less, still more preferably 30 μm or less, and still more preferably 20 μm or less from the viewpoint of effectively improving the electromagnetic wave shielding function.

In recent years, the adhesive tape has been required to be thinned. In the prior art, the adhesive tape using only metal particles is difficult to set the thickness of the conductive adhesive material to 20 μm or less because the metal particles are agglomerated with each other. Since the conductive adhesive of the present invention can relatively reduce the content of the metal particles by using the conductive particles, it is possible to suppress aggregation of the metal particles. As a result, the thickness of the conductive adhesive material can be 20 μm or less, and the thickness of the adhesive tape can be reduced. Furthermore, the adhesive sheet and the adhesive film are contained in the adhesive tape.

The ratio of the thickness of the conductive adhesive material to the particle diameter of the conductive particles (the thickness of the conductive adhesive material / the particle diameter of the conductive particles) is preferably 0.125 or more, more preferably before being bonded to the adherend. It is 0.3 or more, more preferably 0.5 or more, more preferably 20 or less, still more preferably 10 or less, still more preferably 5 or less, still more preferably 1.8 or less. When the ratio is equal to or higher than the lower limit and equal to or lower than the upper limit, the electromagnetic wave shielding function is effectively increased.

(metal particles)

The metal particles are metal particles formed of a metal at both a central portion and a surface portion. The metal particles do not have substrate particles that do not contain metal particles at the center portion. center The metal species of the portion and the surface portion or the ratio thereof may be the same or different.

The metal of the metal particles is not particularly limited. Examples of the metal of the material of the metal particles include gold, silver, copper, palladium, rhodium, iridium, ruthenium, lithium, platinum, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, and ruthenium. , bismuth, antimony, bismuth, cadmium, antimony, tungsten, molybdenum and the like. Further, examples of the metal include tin-doped indium oxide (ITO), solder, and the like.

Since the electromagnetic wave shielding function can be effectively improved, it is preferably an alloy containing tin, nickel, palladium, silver, copper or gold, more preferably nickel, palladium, copper or silver, and further preferably nickel, palladium or copper. More preferably, the conductive portion contains nickel, phosphorus or boron. The material of the metal particles may be an alloy containing phosphorus or boron. The metal particles may also alloy nickel with tungsten or molybdenum.

The content of nickel, palladium, copper or silver in 100% by weight of the metal particles is preferably 10% by weight or more, more preferably 25% by weight or more, still more preferably 40% by weight or more, and preferably 100% by weight ( The total amount is below. It is preferable that the content of nickel in the metal particles is not less than the above lower limit and not more than the above upper limit.

The metal particles preferably contain nickel as a main metal. Regarding the metal particles, the content of nickel is preferably 50% by weight or more based on 100% by weight of the whole. The content of nickel in 100% by weight of the metal particles is preferably 65% by weight or more, more preferably 80% by weight or more, still more preferably 90% by weight or more. When the content of nickel is at least the above lower limit, the electromagnetic wave shielding function is effectively increased.

The content of the metal particles in 100% by weight of the conductive adhesive is preferably 1% by weight or more, more preferably 5% by weight or more, preferably 25% by weight or less, and more preferably 15% by weight or less. When the content of the metal particles is not less than the above lower limit and not more than the above upper limit, the electromagnetic wave shielding function is effectively increased. In the present invention, since conductive particles are also used in addition to the metal particles, even if the content of the metal particles is small, the electromagnetic wave shielding function can be sufficiently improved.

(conductive particles)

Fig. 2 is a cross-sectional view showing conductive particles used in a conductive adhesive material in a conductive adhesive material with a conductive substrate according to an embodiment of the present invention.

The conductive particles 1 shown in FIG. 2 include a substrate particle 2, a conductive portion 3, and a core material 4.

The conductive portion 3 is disposed on the surface of the substrate particle 2. The conductive particles 1 are coated particles in which the surface of the substrate particles 2 is coated with the conductive portion 3 . The conductive portion 3 is a continuous film.

The conductive particles 1 have a plurality of protrusions on the surface of the conductivity. The conductive portion 3 has a plurality of protrusions 3a on the outer surface.

A plurality of core materials 4 are disposed on the surface of the substrate particles 2. The plurality of core materials 4 are disposed inside the conductive portion 3 and buried in the conductive portion 3. The conductive portion 3 is coated with a plurality of core materials 4. The outer surface of the conductive portion 3 is embossed by a plurality of core materials 4 to form protrusions 3a. In order to form the protrusions 3a, the conductive particles 1 are provided with a core material 4 that bulges the outer surface of the conductive portion 3.

Fig. 3 is a cross-sectional view showing a first modification of the conductive particles.

The conductive particles 1A shown in FIG. 3 include the substrate particles 2 and the conductive portion 3A.

The conductive portion 3A is disposed on the surface of the substrate particle 2. The conductive particles 1A have a plurality of protrusions on the surface of the conductivity. The conductive portion 3A has a plurality of protrusions 3Aa on the outer surface.

The conductive particles 1A do not have a core material. The conductive portion 3A has a first portion and a second portion having a thickness thicker than the first portion. The portion other than the plurality of protrusions 3Aa is the above-described first portion of the conductive portion 3A. The plurality of protrusions 3Aa are the second portions of the conductive portion 3A having a relatively large thickness.

As in the case of the conductive particles 1A, it is not necessary to use a core material in order to form protrusions.

Fig. 4 is a cross-sectional view showing a second modification of the conductive particles.

The conductive particles 1B shown in FIG. 4 include a substrate particle 2, a conductive portion 3B, and a core material 4.

The conductive particles 1B have a plurality of protrusions on the surface of the conductivity. Conductive portion 3B is outside The surface has a plurality of protrusions 3Ba.

The position of the core material of the conductive particles 1 and the conductive particles 1B and the conductive portion are different. The conductive particles 1 are formed with a conductive portion 3 having a single layer structure, whereas the conductive particles 1B are formed with a plurality of (two layers) conductive portions 3B.

The conductive portion 3B has a first conductive portion 3BA and a second conductive portion 3BB. The first and second conductive portions 3BA and 3BB are disposed on the surface of the substrate particle 2 . The first conductive portion 3BA is disposed between the substrate particles 2 and the second conductive portion 3BB. Therefore, the first conductive portion 3BA is disposed on the surface of the substrate particle 2, and the second conductive portion 3BB is disposed on the surface of the first conductive portion 3BA. The first conductive portion 3BA is formed in a spherical shape. The first conductive portion 3BA does not have a protrusion on the outer surface. The second conductive portion 3BB has a plurality of protrusions 3BBa on the outer surface.

A plurality of core materials 4 are disposed on the surface of the first conductive portion 3BA. The plurality of core materials 4 are disposed inside the second conductive portion 3BB and are buried in the second conductive portion 3BB. The second conductive portion 3BB is coated with a plurality of core materials 4. The outer surface of the conductive portion 3B is embossed by a plurality of core materials 4 to form protrusions 3Ba. The outer surface of the second conductive portion 3BB is embossed by a plurality of core materials 4 to form protrusions 3BBa.

Like the conductive particles 1B, the conductive portion may not be one layer or may be a plurality of layers.

Fig. 5 is a cross-sectional view showing a third modification of the conductive particles.

The conductive particles 1C shown in FIG. 5 include a substrate particle 2, a conductive portion 3C, and a core material 4.

The conductive particles 1C have a plurality of protrusions on the surface of the conductivity. The conductive portion 3C has a plurality of protrusions 3Ca on the outer surface.

Since the conductive particles 1B and the conductive particles 1C have different positions of the core material, only the conductive portions are different.

The conductive portion 3C has a first conductive portion 3CA and a second conductive portion 3CB. The first and second conductive portions 3CA and 3CB are disposed on the surface of the substrate particle 2 . The first conductive portion 3CA is disposed between the substrate particles 2 and the second conductive portion 3CB. Therefore, the first surface is disposed on the surface of the substrate particle 2 In the conductive portion 3CA, the second conductive portion 3CB is disposed on the surface of the first conductive portion 3CA. The first conductive portion 3CA has a plurality of protrusions 3CAa on the outer surface. The second conductive portion 3CB has a plurality of protrusions 3CBa on the outer surface.

A plurality of core materials 4 are disposed on the surface of the substrate particles 2. The plurality of core materials 4 are disposed inside the conductive portion 3C and buried in the conductive portion 3C. The plurality of core materials 4 are disposed inside the first conductive portion 3CA and buried in the first conductive portion 3CA. The conductive portion 3C is coated with a plurality of core materials 4. The outer surface of the conductive portion 3C is embossed by a plurality of core materials 4 to form protrusions 3Ca. The first conductive portion 3CA is coated with a plurality of core materials 4. The outer surface of the first conductive portion 3CA is embossed by a plurality of core materials 4 to form protrusions 3CAa, and further, protrusions 3CBa are formed.

The volume resistivity of the conductive particles is preferably 0.1 Ω ‧ cm or less, more preferably 0.02 Ω ‧ cm or less, and still more preferably 0.001 Ω ‧ cm or less from the viewpoint of effectively improving the electromagnetic wave shielding function. The volume resistivity is a powder resistance tester ("MCP-PD51 type" manufactured by Mitsubishi Chemical Corporation, ANALYTECH Co., Ltd.), and 2.5 g of powder is used, and a powder-specific probe is used under a pressure of 20 kN. The assay was performed using a Loresta GX MCP-T700.

The particle diameter of the conductive particles is preferably 3 μm or more, more preferably 5 μm or more, further preferably 10 μm or more, particularly preferably 15 μm or more, preferably 40 μm or less, more preferably 35 μm or less, still more preferably 30 μm or less. It is preferably 25 μm or less. When the particle diameter of the conductive particles is at least the above lower limit, the thickness of the conductive adhesive material can be sufficiently ensured, and the contact area between the conductive particles and the adherend becomes large, so that the electromagnetic wave shielding function is further increased.

The ratio of the particle diameter of the conductive particles to the particle diameter of the metal particles (the particle diameter of the conductive particles/the particle diameter of the metal particles) is preferably 0.7 or more, more preferably 1 or more, still more preferably 15 or more. More preferably, it is 20 or more, preferably 5,000 or less, more preferably 4,000 or less, still more preferably 500 or less. If the ratio is equal to or higher than the lower limit and equal to or lower than the upper limit, the electricity is The magnetic wave shielding function is effectively increased.

When the conductive particles and the metal particles are in a true spherical shape, the diameter of each of the conductive particles and the metal particles is a true spherical shape, and when the conductive particles and the metal particles are not in a true spherical shape, the conductive particles and the metal particles are not in a true spherical shape. , indicating the maximum diameter.

The average height of the protrusions is preferably 30 nm or more, more preferably 100 nm or more, still more preferably 500 nm or more, and more preferably 1000 nm or less. When the average height of the protrusions is equal to or higher than the lower limit, the contact between the protrusions and the electromagnetic wave shielding function are further increased. When the average height of the projections is equal to or less than the above upper limit, the projections are less likely to be excessively bent.

The average height of the protrusions is an average of the heights of the protrusions included in one conductive particle. The height of the protrusions indicates an imaginary line of the conductive portion when the center of the conductive particles and the tip of the protrusion (the broken line L1 shown in FIG. 2) are assumed to be free from protrusions (dashed line L2 shown in FIG. 2). The distance from the top (on the outer surface of the spherical conductive particles in the case of no protrusion) to the tip of the protrusion. That is, in Fig. 2, the distance from the intersection of the broken line L1 and the broken line L2 to the tip end of the protrusion is shown.

The surface area of the portion where the protrusion is located is preferably 0.1% or more, more preferably 100% of the total surface area of the outer surface of the conductive portion, from the viewpoint of effectively improving the contact between the protrusion and the electromagnetic wave shielding function. 10% or more, further preferably 30% or more. The upper limit of the ratio of the surface area of the portion where the protrusion is located is 100% of the total surface area of the outer surface of the conductive portion. The surface area of the portion where the protrusion is located may be 99% or less, or 95% or less, in the total surface area of the outer surface of the conductive portion.

The ratio of the surface area of the portion where the protrusion is located can be measured by observing the conductive particles by a scanning electron microscope (SEM), and calculating the projected area of the portion where the protrusion is located with respect to the particle diameter of the conductive particles. The ratio of projected area.

The content of the conductive particles is preferably 1 in 100% by weight of the conductive adhesive material. The weight% or more is more preferably 5% by weight or more, more preferably 30% by weight or less, still more preferably 25% by weight or less, still more preferably 20% by weight or less. When the content of the conductive particles is not less than the above lower limit and not more than the above upper limit, the electromagnetic wave shielding function is effectively increased.

[Substrate particles]

The substrate particles are substrate particles that do not contain metal particles. Examples of the substrate particles include resin particles, inorganic particles not containing metal particles, and organic-inorganic hybrid particles. The substrate particles are preferably resin particles, inorganic particles not containing metal particles, or organic-inorganic hybrid particles. The substrate particles may have a core and a shell disposed on the surface of the core, or may be core-shell particles. The above-mentioned core may be an organic core, and the above shell may be an inorganic shell.

The substrate particles are preferably resin particles or organic-inorganic hybrid particles, and may be resin particles or organic-inorganic hybrid particles. By using such preferred substrate particles, conductive particles more suitable for electromagnetic wave shielding materials can be obtained.

When the electromagnetic wave shielding material is attached to the adherend, the electromagnetic wave shielding material is pressed against the adherend. When the substrate particles are resin particles or organic-inorganic hybrid particles, the conductive particles are easily deformed during extrusion, and the contact area between the conductive particles and the adherend is increased. Therefore, the electromagnetic wave shielding function is further increased.

As the resin for forming the above resin particles, various organic materials can be preferably used. Examples of the resin for forming the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; and polymethacrylic acid; Acrylic resin such as methyl ester or polymethyl acrylate; polyalkylene terephthalate, polycarbonate, polyamine, phenol formaldehyde resin, melamine formaldehyde resin, benzoguanidine formaldehyde resin, urea formaldehyde resin, phenol resin, Melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyfluorene, polyphenylene ether, polyacetal, polyimine, polyamidimide, poly Ether ether ketone, polyether oxime, and a polymer obtained by polymerizing one or two or more kinds of polymerizable monomers having an ethylenically unsaturated group. Because it can be designed and synthesized suitable for electromagnetic wave shielding materials The resin particles having the physical properties at the time of compression can easily control the hardness of the substrate particles to an appropriate range. Therefore, the resin for forming the resin particles preferably has one or more kinds of ethylenicity. A polymer obtained by polymerizing an unsaturated group-containing polymerizable monomer.

When the polymerizable monomer having an ethylenically unsaturated group is polymerized to obtain the above resin particles, examples of the polymerizable monomer having an ethylenically unsaturated group include non-crosslinkable monomers and crosslinking. Sexual monomer.

Examples of the non-crosslinkable monomer include styrene monomers such as styrene and α-methylstyrene; and carboxyl groups such as (meth)acrylic acid, maleic acid, and maleic anhydride. Monomer; methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (a) Base) lauryl acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, (meth) acrylate Alkyl (meth) acrylate compound such as ester; 2-hydroxyethyl (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate, glycidyl (meth) acrylate a (meth) acrylate compound containing an oxygen atom; a nitrile group-containing monomer such as (meth)acrylonitrile; a vinyl ether compound such as methyl vinyl ether, ethyl vinyl ether or propyl vinyl ether; Vinyl ester compounds such as vinyl ester, vinyl butyrate, vinyl laurate, vinyl stearate; unsaturated hydrocarbons such as ethylene, propylene, isoprene, butadiene; and trifluoromethyl (meth)acrylate A halogen-containing monomer such as pentafluoroethyl (meth)acrylate, vinyl chloride, vinyl fluoride or chlorostyrene.

Examples of the crosslinkable monomer include tetramethylol methane tetra(meth)acrylate, tetramethylol methane tri(meth)acrylate, and tetramethylolmethane di(meth)acrylate. Ester, trimethylolpropane tri(meth) acrylate, dipentaerythritol hexa(meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri(meth) acrylate, glycerol di(methyl) Acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)1,4-butanediol di(meth)acrylate, 1,4 -butanediol di(methyl) a polyfunctional (meth) acrylate compound such as acrylate; triallyl (iso) cyanurate, triallyl trimellitate, divinylbenzene, diallyl phthalate, diallyl propylene A monomer containing decane such as guanamine, diallyl ether, γ-(meth)acryloxypropyltrimethoxydecane, trimethoxydecylstyrene or vinyltrimethoxydecane.

The above resin particles can be obtained by polymerizing the above polymerizable monomer having an ethylenically unsaturated group by a known method. Examples of the method include a method in which suspension polymerization is carried out in the presence of a radical polymerization initiator, and a method in which a monomer is swelled by polymerization using a non-crosslinked seed particle together with a radical polymerization initiator. .

In the case where the substrate particles are inorganic particles or organic-inorganic hybrid particles which do not contain metal particles, examples of the inorganic material for forming the substrate particles include cerium oxide, aluminum oxide, barium titanate, zirconia and Carbon black and so on. The above inorganic substance is preferably not a metal. The particles formed by the above-mentioned ceria are not particularly limited, and examples thereof include hydrolyzing an anthracene compound having two or more hydrolyzable alkoxyalkyl groups to form crosslinked polymer particles, as needed. The particles obtained by baking are obtained. Examples of the organic-inorganic hybrid particles include an alkoxysilane alkyl polymer obtained by crosslinking and an organic-inorganic hybrid particle formed by an acrylic resin.

The organic-inorganic hybrid particles are preferably core-shell type organic-inorganic hybrid particles having a core and a shell disposed on the surface of the core. Preferably, the core is an organic core. Preferably, the shell is an inorganic shell. In view of effectively improving the electromagnetic wave shielding function, the substrate particles are preferably organic-inorganic hybrid particles having an organic core and an inorganic shell disposed on the surface of the organic core.

Examples of the material for forming the organic core include a resin or the like for forming the resin particles.

Examples of the material for forming the inorganic shell include inorganic materials for forming the substrate particles. The material for forming the above inorganic shell is preferably cerium oxide. Preferably, the inorganic shell is made of a metal alkoxide by a sol-gel method on the surface of the core After the shell is formed, the shell is sintered to form. The metal alkoxide is preferably a decane alkoxide. The above inorganic shell is preferably formed by a decane alkoxide.

The thickness of the shell is preferably 100 nm or more, more preferably 200 nm or more, more preferably 5 μm or less, still more preferably 3 μm or less. When the thickness of the shell is not less than the above lower limit and not more than the above upper limit, conductive particles more suitable for the electromagnetic wave shielding material can be obtained. The thickness of the above shell is the average thickness of each of the substrate particles. The thickness of the above shell can be controlled by the control of the sol-gel method.

The conductive portion is preferably a conductive layer. The metal which is the material of the above-mentioned conductive portion is not particularly limited. Examples of the metal of the material of the conductive portion include gold, silver, copper, palladium, rhodium, iridium, ruthenium, lithium, platinum, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, ruthenium. , bismuth, antimony, bismuth, cadmium, antimony, tungsten, molybdenum and the like. Further, examples of the metal include tin-doped indium oxide (ITO), solder, and the like.

Since the electromagnetic wave shielding function can be effectively improved, it is preferably an alloy containing tin, nickel, palladium, silver, copper or gold, more preferably nickel, palladium, copper or silver, and further preferably nickel, palladium or copper. More preferably, the conductive portion contains nickel, phosphorus or boron. The material of the conductive portion may be an alloy containing phosphorus or boron. The conductive portion may also alloy nickel with tungsten or molybdenum.

The content of nickel, palladium, copper or silver in the above-mentioned conductive portion is preferably 10% by weight or more, more preferably 25% by weight or more, still more preferably 40% by weight or more, and more preferably 100% by weight ( The total amount is below. It is preferable that the content of nickel in the conductive portion is not less than the above lower limit and not more than the above upper limit.

The conductive portion preferably contains nickel as a main metal. The content of nickel is preferably 50% by weight or more in 100% by weight of the entire conductive portion containing nickel. The content of nickel in 100% by weight of the conductive portion containing nickel is preferably 65% by weight or more, more preferably 80% by weight or more, still more preferably 90% by weight or more. When the content of nickel is at least the above lower limit, the electromagnetic wave shielding function is effectively increased.

The method for measuring the content of the metal contained in the conductive portion can be any known analytical method, and is not particularly limited. Examples of the measurement method include an absorbance analysis method, a spectroscopic analysis method, and the like. As the above-mentioned light absorption analysis method, a flame absorption photometer, an electric heating furnace absorbance photometer, or the like can be used. Examples of the spectral analysis method include a plasma luminescence analysis method and a plasma ion source mass spectrometry method.

When measuring the content of the metal contained in the conductive portion, an ICP (inductively coupled plasma) luminescence analyzer is preferably used. As a commercial item of an ICP luminescence analyzer, the ICP luminescence analyzer manufactured by HORIBA company, etc. are mentioned.

Preferably, the conductive portion contains phosphorus or boron, and the conductive portion containing nickel preferably contains phosphorus or boron. In the case where the conductive portion contains phosphorus or boron, the total content of phosphorus and boron in 100% by weight of the conductive portion containing phosphorus or boron is preferably 0.1% by weight or more, more preferably 1% by weight or more, and further It is preferably 3% by weight or more, preferably 10% by weight or less. When the total content of phosphorus and boron is at most the above upper limit, the electric resistance of the conductive portion is further lowered, and the electromagnetic wave shielding function is effectively increased.

As a method of controlling the content of nickel, phosphorus, and boron in the conductive portion, for example, a method of controlling the pH of the nickel plating solution when the conductive portion is formed by electroless nickel plating, and electroless plating is used. a method of adjusting a concentration of a reducing agent containing boron when forming a conductive portion of nickel, a method of adjusting a concentration of a reducing agent containing phosphorus when forming a conductive portion by electroless nickel plating, and a nickel in a nickel plating solution The method of adjusting the concentration, etc.

The conductive portion may be formed of one layer or may be formed of a plurality of layers (multilayers). That is, the conductive portion may be a single layer or may have a laminated structure of two or more layers. In the case where the conductive portion is a plurality of conductive portions, the conductive portion located at the outermost side of the conductive portion has a plurality of protrusions on the outer surface. In the case where the conductive portion is formed of a plurality of layers, the outermost layer is preferably a gold layer, a nickel layer, a palladium layer, a copper layer or an alloy layer containing tin and silver, more preferably a gold layer or a palladium layer, and particularly preferably a gold layer. . When the outermost layer is the preferred conductive portion, the electromagnetic wave shielding function is effectively changed. high. Further, when the outermost layer is a gold layer, the corrosion resistance is further increased.

The method of forming the conductive portion on the surface of the particle is not particularly limited. Examples of the method of forming the conductive portion include a method of electroless plating, a method by electroplating, a method of physical vapor deposition, and a method of applying a metal powder or a solder paste containing a metal powder and a binder to particles. The method of the surface, etc. Since the formation of the conductive portion is relatively simple, it is preferably a method by electroless plating. Examples of the method of physical vapor deposition include vacuum vapor deposition, ion plating, and ion sputtering.

The thickness of the conductive portion (the thickness of the entire conductive portion) is preferably 0.005 μm or more, more preferably 0.01 μm or more, more preferably 10 μm or less, still more preferably 1 μm or less, further preferably 0.5 μm or less, and particularly preferably 0.3. Below μm. The thickness of the conductive portion is the thickness of the entire conductive layer when the conductive portion is a plurality of layers. When the thickness of the conductive portion is not less than the above lower limit and not more than the above upper limit, the electromagnetic wave shielding function is effectively increased.

When the conductive portion is formed of a plurality of layers, the thickness of the outermost conductive layer is preferably 0.001 μm or more, more preferably 0.01 μm or more, more preferably 0.5 μm or less, and still more preferably 0.1 μm or less. When the thickness of the outermost conductive layer is not less than the above lower limit and not more than the above upper limit, the coating of the outermost conductive layer becomes uniform, and the electromagnetic wave shielding function is effectively increased. Further, in the case where the outermost layer is a gold layer, the thinner the thickness of the gold layer, the lower the cost becomes.

The thickness of the conductive portion can be measured, for example, by observing a cross section of the conductive particles using a field emission scanning electron microscope (FE-SEM).

The obtained conductive particles were added to "Technovit 4000" manufactured by Kulzer Co., Ltd. at a content of 30% by weight, and dispersed to prepare a buried resin for conductive particle inspection. A cross section of the conductive particles was cut out by using an ion polishing apparatus ("IM4000" manufactured by Hitachi High-Technologies Co., Ltd.) so as to be dispersed in the vicinity of the center of the conductive particles embedded in the inspection embedded resin.

Then, it is preferred to use a field emission scanning electron microscope (FE-SEM) to image The magnification was set to 50,000 times, and 50 conductive particles were randomly selected, and the conductive portions of the respective conductive particles were observed. Preferably, the thickness of the conductive portion of the obtained conductive particles is measured and arithmetically averaged to obtain the thickness of the conductive portion.

[core material]

By embedding the core material in the conductive portion, it is easy to cause the conductive portion to have a plurality of protrusions on the outer surface.

The method of forming the protrusions includes a method of forming a conductive portion by electroless plating after attaching a core material to a surface of a substrate particle, and attaching a core portion to a surface of the substrate particle by electroless plating. Further, a method of forming a conductive portion by electroless plating or the like is provided. Another method for forming the protrusions is a method in which a first conductive portion is formed on a surface of a substrate particle, a core material is disposed on the first conductive portion, and then a second conductive portion is formed, and a substrate particle is formed. A method of adding a core material in the middle of the conductive portion (the first conductive portion or the second conductive portion, etc.) on the surface thereof is formed. Further, in order to form the protrusions, it is also possible to use a method of forming an electroconductive portion by electroless plating on the substrate particles without using the above-mentioned core material, and then depositing the electroplated protrusions on the surface of the electroconductive portion, thereby performing electroless plating. A conductive portion is formed.

Examples of the method of disposing the core material on the surface of the substrate particles or the conductive portion include a method of adding a core material to the dispersion of the particles, for example, by collecting and adhering the core material by van der Waals force. The surface of the particles; and the addition of the core material to the container in which the particles are added, and the core material is attached to the surface of the particles by mechanical action such as rotation of the container. Among them, since it is easy to control the amount of the core material to be attached, it is preferred to collect the core material and adhere it to the surface of the substrate particles in the dispersion liquid.

The material of the above core material is not particularly limited. The Mohs hardness of the material of the above core material is preferably higher.

Specific examples of the material of the core material include barium titanate (Mohs hardness of 4.5), nickel (Mohs hardness of 5), cerium oxide (cerium oxide, Mohs hardness of 6 to 7), and titanium oxide (Mo) Hardness 7), zirconia (Mohs hardness 8 to 9), alumina (Mohs hardness 9), tungsten carbide (Mohs hardness 9) and diamond (Mohs hardness 10). The material of the core material is preferably nickel, cerium oxide, titanium oxide, zirconium oxide, aluminum oxide, tungsten carbide or diamond, more preferably cerium oxide, titanium oxide, zirconium oxide, aluminum oxide, tungsten carbide or diamond, and further preferably It is preferably titanium oxide, zirconium oxide, aluminum oxide, tungsten carbide or diamond, and particularly preferably zirconia, alumina, tungsten carbide or diamond. The Mohs hardness of the material of the core material is preferably 4 or more, more preferably 5 or more, still more preferably 6 or more, still more preferably 7 or more, and particularly preferably 7.5, from the viewpoint of effectively improving the electromagnetic wave shielding function. the above.

The shape of the core material is not particularly limited. The shape of the core material is preferably a block shape. Examples of the core material include a particulate block, agglomerates in which a plurality of fine particles are aggregated, and an amorphous block.

The average diameter (average particle diameter) of the core material is preferably 0.001 μm or more, more preferably 0.05 μm or more, more preferably 0.9 μm or less, and still more preferably 0.2 μm or less. When the average diameter of the core material is not less than the above lower limit and not more than the above upper limit, the electromagnetic wave shielding function is effectively increased.

The "average diameter (average particle diameter)" of the above core material means a number average diameter (number average particle diameter). The average diameter of the core material can be determined by observing an arbitrary 50 core materials by an electron microscope or an optical microscope, and calculating an average value.

The number of the protrusions per one of the conductive particles is preferably three or more, and more preferably five or more. The upper limit of the number of the above protrusions is not particularly limited. The upper limit of the number of the above-mentioned protrusions can be appropriately selected in consideration of the particle diameter of the conductive particles and the like.

(adhesive ingredient)

The conductive adhesive of the present invention has an adhesive component, and can be placed on a conductive substrate as described above to form a conductive adhesive sheet or a conductive adhesive tape. Examples of the above-mentioned adhesive component include a rubber-based adhesive, an acrylic adhesive, a polyoxynoxy adhesive, and a polyurethane adhesive. The above adhesive component may be used alone or in combination of two. the above.

The content of the above-mentioned adhesive component is preferably 5% by weight or more, more preferably 15% by weight or more, preferably 60% by weight or less, and more preferably 35% by weight or less based on 100% by weight of the conductive adhesive. When the content of the above-mentioned adhesive component is not less than the above lower limit and not more than the above upper limit, the electromagnetic wave shielding function is effectively increased.

Hereinafter, the present invention will be described in more detail based on specific examples. Furthermore, the invention is not limited to the following examples.

In the following examples, the following conductive particles were used: a powder resistance measuring device ("MCP-PD51 type" manufactured by Mitsubishi Chemical Corporation ANALYTECH Co., Ltd.) was used and 2.5 g of powder was used, and a powder-specific probe was used for 20 kN. When the volume resistivity was measured under pressure and measured by the Loresta GX MCP-T700, the volume resistivity was 0.001 Ω‧ cm or less.

(Example 1)

(1) Preparation of a solution of a conductive adhesive material for forming a conductive adhesive material

Ethyl acetate was used as a solvent, and 0.1 part by weight of azobisisobutyronitrile was used as a starter to make 40 parts by weight of 2-phenoxyethyl methacrylate, 58 parts by weight of n-butyl methacrylate, and methyl group. 2 parts by weight of acrylic acid was polymerized by a solution polymerization method (60 ° C for 4 hours, 85 ° C for 1 hour) to obtain a solution (solid content concentration: 45% by weight) of an acrylic polymer having a weight average molecular weight of about 400,000. 40 parts by weight of a polymerized rosin pentaerythritol ester ("HARIESTER S" manufactured by Harima Chemicals Group Co., Ltd.) as an adhesion-imparting resin was prepared in an amount of 100 parts by weight of the solid content of the acrylic polymer solution to prepare an acrylic resin composition solution.

7 parts by weight of nickel powder ("NFP201X/XD 200nm" manufactured by JFE MINERAL Co., Ltd.) as a metal particle, and conductive particles (NIEZB manufactured by Sekisui Chemical Industry Co., Ltd.) was added to 100 parts by weight of the solid content of the acrylic resin composition solution. -020-S, electroplated metal species of conductive portion: nickel) 8 parts by weight, ethyl acetate 100 parts by weight, and isocyanate 2 parts by weight of a binder ("Coronate L" manufactured by Nippon Polyurethane Co., Ltd.) was mixed with a stirrer for 10 minutes to obtain a solution of an electrically conductive adhesive material (acrylic adhesive solution). The average height of the protrusions of the conductive particles was 500 nm. Moreover, the ratio of the surface area of the portion where the protrusions of the conductive particles were measured by the above method (the coverage ratio by the protrusion) was 30%.

(2) Production of conductive adhesive material with conductive substrate

A copper foil having a thickness of 12 μm was prepared. A conductive adhesive (adhesive layer) was formed on the copper foil by using a solution of the above-mentioned conductive adhesive material so as to have a thickness of 20 μm using a bar coater, and further aged at 50 ° C for conductivity. A conductive adhesive material for the substrate. In the obtained conductive adhesive material, the content of the conductive particles was 8% by weight, and the content of the metal particles was 7% by weight.

(Example 2-3)

A conductive adhesive material to which a conductive substrate is attached is obtained in the same manner as in Example 1 except that the particle diameter of the conductive particles is changed as in Table 1.

(Example 4)

A conductive adhesive material with a conductive base material was obtained in the same manner as in Example 1 except that the particle diameter of the conductive particles and the particle diameter of the metal particles were changed as shown in Table 1.

(Examples 5-8)

A conductive adhesive material with a conductive base material was obtained in the same manner as in Example 1 except that the particle diameter of the metal particles was changed.

(Example 9)

A conductive adhesive material with a conductive base material was obtained in the same manner as in Example 1 except that the particle diameter of the metal particles and the thickness of the conductive adhesive material were changed as shown in Table 1.

(Embodiment 10)

A conductive adhesive material with a conductive substrate was obtained in the same manner as in Example 1 except that the thickness of the conductive adhesive was changed.

(Examples 11-12)

A conductive adhesive material with a conductive base material was obtained in the same manner as in Example 1 except that the particle diameter of the metal particles and the thickness of the conductive adhesive material were changed as shown in Table 1.

(Examples 13-14)

A conductive adhesive material to which a conductive substrate is attached is obtained in the same manner as in Example 1 except that the average height of the protrusions of the conductive particles is changed.

(Examples 15-18)

A conductive adhesive material with a conductive substrate was obtained in the same manner as in Example 1 except that the plating metal of the conductive portion of the conductive particles was changed as in Table 1.

(Examples 19-23)

A conductive adhesive material with a conductive base material was obtained in the same manner as in Example 1 except that the content of the conductive particles and the content of the metal particles in the conductive adhesive material were changed.

(Examples 24-25)

A conductive adhesive material to which a conductive substrate is attached is obtained in the same manner as in Example 1 except that the particle diameter of the conductive particles is changed as in Table 2.

(Examples 26-27)

A conductive adhesive material to which a conductive substrate is attached is obtained in the same manner as in Example 1 except that the average height of the protrusions of the conductive particles is changed.

(Embodiment 28)

A conductive adhesive material with a conductive substrate was obtained in the same manner as in Example 1 except that the thickness of the conductive adhesive was changed as in Table 2.

(Example 29)

A conductive adhesive material with a conductive base material was obtained in the same manner as in Example 1 except that the particle diameter of the conductive particles and the thickness of the conductive adhesive material were changed as in Table 2.

(Embodiment 30)

A conductive adhesive material to which a conductive substrate was attached was obtained in the same manner as in Example 1 except that the particle diameter of the metal particles was changed.

(Examples 31-32)

A conductive adhesive material with a conductive substrate was obtained in the same manner as in Example 4 except that the coverage of the conductive particles by the protrusions was changed as in Table 2.

(Example 33)

In the same manner as in Example 4, a conductive adhesive material with a conductive substrate was obtained in the same manner as in Example 4 except that the plating metal species (layer configuration, outermost layer Ag/inner layer Cu) of the conductive portion of the conductive particles was changed. .

(Comparative Example 1)

The conductive adhesive with a conductive substrate was obtained in the same manner as in Example 1 except that the content of the conductive particles in the conductive adhesive was changed, and the metal particles were not used in the conductive adhesive. material.

(Comparative Example 2)

The conductive adhesion of the conductive substrate was obtained in the same manner as in Example 1 except that the content of the metal particles in the conductive adhesive was changed, and the conductive particles were not used in the conductive adhesive. material.

(Comparative Example 3)

A conductive adhesive material with a conductive base material was obtained in the same manner as in Example 1 except that the conductive particles having no protrusions (the average height of the protrusions was 0 nm) were used.

(Example 34)

A conductive adhesive material with a conductive substrate was obtained in the same manner as in Example 4 except that the coverage of the conductive particles by the protrusions was changed as in Table 2.

(Evaluation)

(1) Adhesion

The test piece (conductive adhesive material with a conductive base material) was attached to the stainless steel plate from the side of the conductive adhesive material, and the force required to peel the test plate in the 180° direction was evaluated. The stretching speed was set to 30 mm/min, and the tape width was set to 25 mm. According to the force required for peeling, the adhesion was judged by the following criteria.

[Standard of adhesion]

○○○: 15N/mm ² or more

○○: 10 N/mm ² or more and less than 15 N/mm ²

○: 4 N/mm ² or more and less than 10 N/mm ²

△: 1 N/mm ² or more and less than 4 N/mm ²

×: not up to 1 N/mm ²

(2) Connection resistance

As shown in Fig. 6, the conductive adhesive material 61 to which the conductive substrate is attached is attached to the lower pure copper electrode 62 (25 × 25 mm) from the side of the adhesive, and is sandwiched by the upper pure copper electrode 63, and is pressurized at 2 MPa. The connection resistance was measured using a four-terminal method. The plane area of the conductive adhesive material to which the conductive substrate was attached was set to 10 × 10 mm. The connection resistance is determined using the following criteria.

[Determination of connection resistance]

○○○: Less than 2Ω

○○: 2 Ω or more and less than 5 Ω

○: 5 Ω or more and less than 10 Ω

△: 10 Ω or more and less than 30 Ω

×: 30 Ω or more

(3) Electromagnetic shielding

The electromagnetic wave shielding property of the conductive adhesive material with a conductive substrate was evaluated using the KEC method (magnetic field) developed by the KEC Kansai Electronics Industry Promotion Center. The shielding effect of the 1 GHz high frequency is used as a comparison reference, and the electromagnetic wave is covered according to the value of the obtained shielding effect. Coverability is evaluated.

[Determination of electromagnetic wave shielding]

○○○: 90dB or more

○○: 75dB or more and less than 90dB

○: 60dB or more and less than 75dB

△: 40dB or more and less than 60dB

×: less than 40dB

(4) Electromagnetic wave shielding durability

The conductive adhesive material with a conductive substrate was subjected to a heat cycle test under the following thermal cycle conditions, and thereafter, the shielding property was evaluated by the KEC method. The shielding effect of the 1 GHz high frequency was used as a comparison standard, and the electromagnetic wave shielding durability was evaluated based on the value of the shielding effect obtained.

Thermal cycling conditions: low temperature side: -10 ° C / 30 min; high temperature side: 120 ° C / 30 min; total 250 cycles.

[Criteria for judging the durability of electromagnetic shielding]

○○○: 80dB or more

○○: 65dB or more and less than 80dB

○: 50dB or more and less than 65dB

△: 40dB or more and less than 50dB

×: less than 40dB

The details and evaluation results of the conductive adhesive material with a conductive substrate are shown in Tables 1 to 3 below.

[Table 1]

1‧‧‧Electrical particles

51‧‧‧ Conductive adhesive materials with conductive substrates

52‧‧‧ Conductive adhesive materials

53‧‧‧Electrically conductive substrate

56‧‧‧Metal particles

57‧‧‧Adhesive ingredients

Claims (12)

A conductive adhesive material comprising a plurality of metal particles, a plurality of conductive particles, and an adhesive component, wherein the conductive particles are provided with substrate particles not containing metal particles, and are disposed on a surface of the substrate particles In the conductive particles of the conductive portion, the conductive particles have a plurality of protrusions on the outer surface of the conductive portion. The conductive adhesive material according to claim 1, wherein the conductive particles are contained in an amount of 1% by weight or more and 30% by weight or less based on 100% by weight of the conductive adhesive. The conductive adhesive material according to claim 1 or 2, wherein the conductive particles have a particle diameter of 3 μm or more and 40 μm or less. The conductive adhesive material according to claim 1 or 2, wherein the conductive particles have a volume resistivity of 0.001 Ω‧ cm or less. The conductive adhesive material according to claim 1 or 2, wherein a ratio of a particle diameter of the conductive particles to a particle diameter of the metal particles is 0.7 or more and 5,000 or less. The conductive adhesive material according to claim 1 or 2, wherein the average height of the protrusions is 30 nm or more and 1000 nm or less. The conductive adhesive material according to claim 1 or 2, wherein a surface area of the portion where the protrusion is located is 100% or more of the total surface area of the outer surface of the conductive portion. The conductive adhesive material according to claim 1 or 2, wherein the conductive particles are provided with a plurality of core materials for bulging the outer surface of the conductive portion. The conductive adhesive material according to claim 8, wherein the material of the core material has a Mohs hardness of 5 or more. The conductive adhesive material according to claim 1 or 2, which has a thickness of 5 μm or more and 40 μm or less. A conductive adhesive material with a conductive substrate, comprising the conductive adhesive material according to any one of claims 1 to 10, and a conductive substrate, wherein the conductive adhesive material is disposed on the conductive substrate On the surface. The conductive adhesive material of the conductive substrate according to claim 11, wherein the conductive substrate is a copper foil.