CN1938904A - Anisotropic conductive film and manufacturing method thereof - Google Patents

Abstract

An anisotropic conductive film, which is applicable to a narrower pitch of an object to be connected, while maintaining connection reliability, is provided at a low cost compared with the conventional ones. A method for manufacturing such anisotropic conductive film is also provided. The anisotropic conductive film is provided with a porous film. The film has many hole parts which penetrate in the film thickness direction, being arranged in a honeycomb state with their inner wall surfaces bent in the external direction, and are formed of a polymer. The film is also provided with a conductive material applied in the holes of the porous film, and an adhesive layer covering the both sides of the porous film. The porous film is formed by a method wherein the polymer is melt in a volatile organic solvent which does not mix with water and a supporting board made by casting the polymer solution is permitted to exist under a high moisture condition.

Description

Anisotropic conductive film and manufacturing method thereof

technical field

The present invention relates to an anisotropic conductive film and a manufacturing method thereof, and more specifically, to an anisotropic conductive film suitable for use in connection of electronic parts and substrates having narrow conductor intervals, and the manufacturing thereof method.

Background technique

In recent years, along with improvements in performance and miniaturization of electronic equipment, there has been an increasing need to electrically connect a plurality of conductors arranged at narrow pitches. Such a necessity arises, for example, in the liquid crystal display (Liquid Crystal Display: LCD) field, the electrode and The case of connecting the electrodes of the liquid crystal panel, and the case of directly connecting (Chip On Glass: COG) driving ICs on the glass substrate of the liquid crystal panel, etc.

In the connection described above, generally, anisotropic conductive film (Anisotropic Conductive Film: ACF) that exhibits conductivity in the film thickness direction and insulation in the film surface direction is widely used. Figure 16 shows the structure of a representative ACF and the principle of its linkage.

As shown in FIG. 16( a )( b ), generally known ACF 100 has a structure in which conductive particles 102 are dispersed in film-shaped adhesive resin 101 . When the ACF 100 is placed between the chip 103 and the substrate 104, for example, for thermocompression bonding, the resin 101 is flowed out, and at the same time, the conductive particles 102 are sandwiched between the chip electrode 105 and the substrate electrode 106 in a crushed state. . Then, when the resin 101 is cured while maintaining this state, an electrical connection is made between the electrodes 105 and 106 via the conductive particles 102 . On the other hand, the adjacent electrodes 105 (106) are electrically insulated by the resin 101 . In addition, the chip 103 and the substrate 104 are mechanically connected by curing of the resin 101 .

Here, the main purposes of using conductive particles include, for example, (1) to electrically connect electrodes, (2) to insulate circuits, and (3) to absorb variations in electrode height and substrate warpage.

In order to achieve these objects, for example, in Non-Patent Document 1 (Takeichi Motohide, "Anisotropic conductive film ni yoru フイルツプチツププヮミッミ technology", Electronic Materials, Industry Research Society, May 2001 Supplement, p.130-p.133 ) describes that fine resin particles having an elastic deformation region with a diameter of about 3 to 5 μm are plated with a metal such as Ni—Au as conductive particles.

In addition, in the same non-patent document 1, there is a description that uses particles whose surfaces are coated with an insulating material as electroconductive particles. In addition, at this time, in the film thickness direction, since the insulating material on the surface of the particle is destroyed by the pressure contact force, the conductive particle and the electrode are electrically connected. On the other hand, in the film surface direction, since the insulating material on the surface of the particles is not broken, the insulating properties are maintained even if the particles come into contact with each other.

In addition, Patent Document 1 (JP-A-8-273442) describes an ACF different from the ACF shown in FIG. The holes are filled with conductive substances.

但是，在非专利文献2(下村政嗣，「高分子材料の自己組織化によるナノ·メゾホ一ル構造の形成と機能化」，機能材料，株式会社ツ一エムツ一出版，2003年10月，vol .23, No.10, p.18-p.26) and non-patent literature 3 (Masatsugu Shimomura, "Self-Organized によるパタン Formation and Maikro Processing Technology ヘの Expansion", Materi, Incorporated Nippon Metal Society, 2003, Vol. 42, No. 6, p.457-p.460), it is not described that ACF is composed of a polymer having a honeycomb structure in which pores are regularly arranged in the film thickness direction. porous membrane.

Also, Patent Document 2 (JP-A-2003-80538) describes a porous membrane made of polyimide having a honeycomb structure in which pores are regularly arranged in the membrane thickness direction, not ACF, either.

When the conductor pitch of the object to be connected becomes narrow due to miniaturization of electronic components, etc., in order to ensure insulation in the film surface direction, in the ACF shown in Figure 16, the size of the conductive particles dispersed in the adhesive resin has to get smaller. However, it is difficult to reduce the size of electroconductive particles beyond the variation in conductor height of the object to be connected from the viewpoint of securing conductivity in the film thickness direction.

Moreover, when making electroconductive particle size small, in order to ensure sufficient electroconductivity, it is necessary to raise the dispersion density of electroconductive particle. However, if the dispersion density of electroconductive particle is made high, it will become difficult to ensure the insulation of a film surface direction, and reliability will fall.

Therefore, with the ACF shown in FIG. 16 , there is a natural limitation corresponding to the narrowing of the pitch of the connected objects. Therefore, there is a problem that it is difficult to further narrow the conductor pitch (currently about 40 μm) of the object to be connected.

On the other hand, for the ACF described in Non-Patent Document 1, it is considered that since the surface of the conductive particles is coated with an insulating material, even if the dispersion density of the conductive particles is increased, it is easy to ensure insulation in the film surface direction. sex. However, even with this ACF, it is difficult to reduce the size of the electroconductive particles beyond the fluctuation of the conductor height that the object to be connected has for the same reason as above. Therefore, even if this ACF is used, there is a natural limitation corresponding to narrowing the pitch of the object to be connected. Of course, there is also the problem that it is difficult to apply an insulating material to fine particles.

In contrast, the ACF described in Patent Document 1 is considered to be easier to cope with narrower pitches of connected objects than ACF in which conductive particles are dispersed in resin because holes penetrating in the film thickness direction are filled with conductive substances. change. However, in this ACF, since many minute penetrating holes are provided in the film thickness direction, it is necessary to use X-rays, SR (synchronous radiation), or the like. Therefore, there are problems in that the manufacturing cost increases and the mass productivity of elongated objects is also poor.

In addition, Non-Patent Document 2 and Non-Patent Document 3 describe that a porous membrane composed of a polymer having a honeycomb structure in which pores are regularly arranged in the film thickness direction is used as a substrate for culturing cells etc., but there is absolutely no disclosure nor mention of materials used for the anisotropic conductive film.

The problem to be solved by the present invention is to provide an anisotropic conductive film and its production that can correspond to the further narrowing of the pitch of the connected object while maintaining the connection reliability, and which is lower in cost than conventional ones. method.

Contents of the invention

In order to solve the above-mentioned problems, the main point is that the anisotropic conductive film of the present invention has: a porous film made of a polymer, the porous film has many pores penetrating in the film thickness direction, the pores are arranged in a honeycomb shape, and the pores The inner wall is bent toward the outer direction; the conductive substance is filled in the pores of the porous membrane; and the adhesive layer is covered on both sides of the porous membrane.

At this time, the polymer forming the porous membrane is preferably made of polysulfone, polyethersulfone, polyphenylene sulfide, polyimide, polyamideimide, siloxane-modified polyimide, siloxane Modified polyamide-imide, polyetherimide, and polyetheretherketone are composed of one or more polymers.

Here, the above-mentioned porous membrane is preferably formed by allowing a support substrate on which a polymer solution is cast (cast) to exist in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution contains at least: Volatile organic solvents, polymers and amphiphilic substances soluble in the organic solvents.

Alternatively, the above-mentioned porous film and conductive substance are preferably formed by making a support substrate on which a polymer solution casted thereon exist in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution contains at least: Non-toxic organic solvents, polymers soluble in the organic solvents, amphiphilic substances and conductive substances.

When the above-mentioned porous film or the above-mentioned porous film and conductive material are formed by these methods, as the polymer soluble in the above-mentioned organic solvent, a polymer selected from polysulfone, polyethersulfone, polyphenylene sulfide, siloxane, etc. can be suitably used. Modified polyimide, siloxane-modified polyamide-imide 1 type or 2 or more types of polymers, etc.

In addition, the above-mentioned porous film can also be formed by making the support substrate casted with a polymer solution in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution contains at least: hydrophobic and volatile Sexual organic solvents and amphiphilic polymers.

Alternatively, the above-mentioned porous film and conductive substance can also be formed by making the supporting substrate casted with a polymer solution in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution contains at least: Volatile organic solvents, amphiphilic polymers and conductive substances.

When the above-mentioned porous film or the above-mentioned porous film and conductive substance are formed by these methods, as the amphiphilic polymer, a polymer and a cationic lipid having a hydrophilic group introduced into the main chain and/or side chain can be suitably used. Polyionic complexes of substances, such as polyionic complexes of polyamic acid and cationic lipids, etc. In addition, when a polyionic complex of polyamic acid and cationic lipid is used as the amphiphilic polymer, it is preferable that the porous membrane is subjected to an imidization treatment after membrane formation.

In addition, in the anisotropic conductive film of the present invention, it is preferable that the diameter of the holes of the porous film is smaller than the narrowest interval of a plurality of conductors of the object to be connected, and the interval of the holes is smaller than the narrowest width of these conductors. .

Moreover, in the anisotropic conductive film of this invention, it is preferable that the said electroconductive substance consists of the group of electroconductive particle. Metal particles etc. can be suitably used as electroconductive particle. One, or two or more metals selected from Ag, Au, Pt, Ni, Cu, and Pd can be suitably used as the metal of the metal particles. At this time, the group of metal particles filled in the hole can be integrated by fusion bonding.

In addition, in the anisotropic conductive film of the present invention, it is preferable that the adhesive layer is a prepreg in which a thermosetting resin is in a semi-cured state. At this time, an epoxy resin or the like can be suitably used as the thermosetting resin.

On the other hand, the gist of the production method of the anisotropic conductive film of the present invention is that it includes: a step of forming a porous film made of a polymer, the porous film having many holes penetrating in the film thickness direction, and the holes are arranged forming a honeycomb shape, while the inner walls of the pores are bent in the outward direction; filling the pores of the porous membrane with a conductive substance; and coating both sides of the porous membrane with an adhesive layer.

Here, the above-mentioned porous membrane is preferably formed by allowing a support substrate on which a polymer solution is casted to exist in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution contains at least hydrophobic and volatile organic compounds. Solvents, polymers and amphiphilic substances soluble in the organic solvent.

Alternatively, the above-mentioned porous membrane is preferably formed by allowing a support substrate on which a polymer solution is cast to exist in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution contains at least: a hydrophobic and volatile organic solvent and amphiphilic polymers.

In addition, the gist of another manufacturing method of the anisotropic conductive film of the present invention is that it includes: a step of forming a porous film made of a polymer, the porous film having many holes penetrating in the film thickness direction, and the holes are arranged forming a honeycomb shape, while the inner walls of the pores are bent in the outward direction, and the pores are filled with a conductive substance; and the process of covering both sides of the porous membrane with an adhesive layer.

Here, the above-mentioned porous membrane in which the pores are filled with a conductive substance is preferably formed by allowing a support substrate on which a polymer solution is cast to exist in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution is at least Contains: a hydrophobic and volatile organic solvent, a polymer soluble in the organic solvent, an amphiphilic substance, and a conductive substance.

Alternatively, the above-mentioned porous membrane filled with a conductive substance in the pores is preferably formed by allowing a support substrate on which a polymer solution is cast to exist in an atmosphere with a relative humidity of 50% or more, wherein the polymer solution contains at least : Hydrophobic and volatile organic solvents, amphiphilic polymers and conductive substances.

The anisotropic conductive film of the present invention includes a porous film having many fine pores arranged in a honeycomb shape, and the pores of the porous film are filled with a conductive substance.

Therefore, even when the conductor pitch of the object to be connected is narrowed, if the diameter and interval of the holes formed in a honeycomb shape are reduced, it is possible to easily respond to the narrowed pitch. In addition, since the adjacent holes are separated from each other and the conductive substance is filled in these holes, the conduction in the film thickness direction and the insulation in the film surface direction can be sufficiently ensured. Therefore, according to the anisotropic conductive film of the present invention, compared with the conventional anisotropic conductive film in which conductive particles are dispersed in the resin, it is possible to further narrow the distance between the corresponding object to be connected while maintaining the connection reliability. Spacing.

In addition, the above-mentioned porous membrane can be easily formed by, for example, a method in which a support substrate on which a polymer solution is casted, wherein the polymer solution contains at least hydrophobic and volatile organic solvent, a polymer soluble in the organic solvent, an amphiphilic substance and a conductive substance, or at least contain: a hydrophobic and volatile organic solvent and an amphiphilic polymer.

Therefore, although many minute holes are provided in the film thickness direction, it is absolutely unnecessary to use expensive X-rays, SR (synchrotron radiation), and the like. Therefore, the anisotropic conductive film of the present invention is advantageous in that it can be produced simply and inexpensively, and that elongated objects can also be mass-produced easily.

At this time, the polymer forming the porous membrane is selected from polysulfone, polyethersulfone, polyphenylene sulfide, polyimide, polyamideimide, siloxane-modified polyimide, siloxane The heat resistance of the anisotropic conductive film is excellent when the modified polyamideimide, polyetherimide, and polyetheretherketone are composed of one or more polymers.

In addition, when the above-mentioned porous film and conductive material are formed by making the support substrate on which the polymer solution is casted in the atmosphere with a relative humidity of 50% or more, it is possible to more easily form the pores in the film forming process. A porous membrane filled with a conductive substance, wherein the polymer solution contains at least: a hydrophobic and volatile organic solvent, a polymer soluble in the organic solvent, an amphiphilic substance, and a conductive substance, or Contain at least: hydrophobic and volatile organic solvents, amphiphilic substances and conductive substances.

Therefore, an anisotropic conductive film using such a porous film is advantageous in that it can be manufactured more simply and inexpensively because it does not need to refill the pores of the porous film with a conductive substance, and it is also easy to mass-produce industrially, etc. .

In addition, when forming a porous film, or a porous film and a conductive substance by the above method, polyionic complexation using a polymer and a cationic lipid having a hydrophilic group introduced into the main chain and/or side chain When amphiphilic polymers such as polyionic complexes of polyamic acid and cationic lipids are used as amphiphilic polymers, the anisotropic properties of porous membranes made of polymers that are poorly soluble in hydrophobic organic solvents can be obtained. conductive film.

In addition, when the amphiphilic polymer is a polyionic complex of polyamic acid and cationic lipid, it is possible to obtain a porous membrane made of polyimide by performing imidization treatment after the membrane is formed. Anisotropic conductive film with excellent heat resistance.

In addition, in the anisotropic conductive film of the present invention, the hole diameter of the porous film is smaller than the narrowest interval of a plurality of conductors of the object to be connected, and the interval of the hole is smaller than the narrowest width of these conductors, Insulation in the film surface direction is reliable, and high connection reliability can be obtained.

In addition, in the anisotropic conductive film of the present invention, when the conductive material is composed of a group of conductive particles, the holes are easily filled with conductive particles uniformly, so the conduction in the film thickness direction is excellent. Moreover, when electroconductive particle is a metal particle, the melting point of a metal can be lowered by the reduction of a particle diameter, and it can melt-bond easily at low temperature.

When the groups of metal particles filled in the holes are integrated by fusion bonding, the gaps between the metal particles are reduced, and the contact resistance is reduced, so that the resistance in the film thickness direction can be reduced. In addition, since organic substances and the like present between the metal particles can be removed by fusion bonding, the resistance in the film thickness direction can also be reduced thereby.

At this time, when the metal of the metal particles is composed of one or more kinds selected from Ag, Au, Pt, Ni, Cu, and Pd, since the conductivity is excellent, conduction in the film thickness direction can be easily obtained.

In addition, in the anisotropic conductive film of the present invention, when the adhesive layer is a prepreg in which the thermosetting resin is in a semi-cured state, the adhesive layer is easily discharged by flow in the gap between the conductors of the object to be connected. In addition, Adhesion with the connected part is also improved, and high connection reliability can be ensured.

At this time, when the thermosetting resin is an epoxy resin, the adhesiveness with the connected part is excellent.

On the other hand, according to the manufacturing method of the anisotropic conductive film of the present invention, compared with the conventional type anisotropic conductive film in which the conductive particles are dispersed in the resin, it can be manufactured while maintaining the connection reliability. Anisotropic conductive film with narrower pitch corresponding to objects to be connected.

At this time, when the porous membrane is formed by exposing the support substrate on which the polymer solution is cast in an atmosphere with a relative humidity of 50% or more, a porous membrane having many pores arranged in a honeycomb shape can be easily formed, wherein the The polymer solution at least contains: a hydrophobic and volatile organic solvent, a polymer soluble in the organic solvent, and an amphiphilic substance, or at least contains: a hydrophobic and volatile organic solvent and an amphiphilic high molecular. Therefore, an anisotropic conductive film can be produced inexpensively.

In addition, according to another method for producing an anisotropic conductive film of the present invention, compared with the conventional type anisotropic conductive film in which conductive particles are dispersed in a resin, it is possible to manufacture a corresponding anisotropic conductive film while maintaining connection reliability. An anisotropic conductive film for further narrowing the pitch of connectors.

At this time, when the porous membrane in which the conductive substance is filled in the pores is formed by making the supporting substrate on which the polymer solution is cast in an atmosphere with a relative humidity of 50% or more, it is not necessary to place a layer in the pores of the porous membrane. The conductive material is filled again, so the anisotropic conductive film can be manufactured more cheaply, wherein, the polymer solution contains at least: a hydrophobic and volatile organic solvent, a polymer soluble in the organic solvent, an amphiphilic Sexual substances and conductive substances, or at least contain: hydrophobic and volatile organic solvents, amphiphilic polymers and conductive substances.

Description of drawings

FIG. 1 is a cross-sectional view schematically showing the structure of the anisotropic conductive film of the present invention.

2 is a diagram schematically showing the structure of a porous film in the anisotropic conductive film of the present invention, (a) is a cross-sectional view of the porous film, and (b) is a plan view of the porous film.

FIG. 3 is a diagram schematically showing a state in which pores of the porous membrane shown in FIG. 2 are filled with a conductive substance.

Fig. 4 is a diagram schematically showing the principle of spontaneous formation of a porous membrane having many pores arranged in a honeycomb shape.

Fig. 5 is a diagram schematically illustrating a method of using the anisotropic conductive film of the present invention.

6 is an electron micrograph of a porous membrane made of polysulfone obtained when the anisotropic conductive membrane of Example 1 was produced.

7 is an electron micrograph of a porous film in which Ag particles are filled in pores obtained when the anisotropic conductive film of Example 1 was produced.

8 is an electron micrograph of a porous membrane made of polysulfone obtained when the anisotropic conductive membrane of Example 2 was produced.

9 is an electron micrograph of a porous film in which Ag particles are filled in pores obtained when the anisotropic conductive film of Example 2 was produced.

10 is an electron micrograph of a porous film made of siloxane-modified polyimide obtained when the anisotropic conductive film of Example 3 was produced.

11 is an electron micrograph of a porous film in which Ag particles are filled in pores obtained when the anisotropic conductive film of Example 3 was produced.

12 is an electron micrograph of a porous film made of siloxane-modified polyimide obtained when the anisotropic conductive film of Example 4 was produced.

13 is an electron micrograph of a porous film in which Ag particles are filled in pores obtained when the anisotropic conductive film of Example 4 was produced.

FIG. 14 is a diagram schematically showing a comb-shaped electrode used for evaluation of anisotropic conductivity.

FIG. 15( a ) is a diagram schematically illustrating evaluation of electrical conductivity in the film thickness direction, and FIG. 15( b ) is a diagram schematically illustrating evaluation of insulation performance in the film surface direction.

FIG. 16 is a diagram showing the structure of a typical conventional anisotropic conductive film and its connection principle.

Detailed ways

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing the structure of the anisotropic conductive film of the present invention. In addition, FIG. 2 is a diagram schematically showing the structure of a porous film in the anisotropic conductive film of the present invention. In addition, FIG. 3 is a diagram schematically showing a state in which the pores of the porous membrane shown in FIG. 2 are filled with a conductive substance.

First, the structure of the anisotropic conductive film (henceforth "this ACF") of this invention is demonstrated using FIGS. 1-3.

As shown in FIG. 1 , this ACF 10 has a porous membrane 12 , a conductive substance 14 , and an adhesive layer 16 as a basic structure.

In the present ACF10, the porous membrane 12 is formed of a polymer, and has many pores 18 penetrating in the membrane thickness direction as shown in FIG. 2( a ). In addition, the inner wall surfaces 22 of these hole portions 18 are curved outward in a substantially spherical shape. In addition, as shown in FIG. 2( b ), these hole portions 18 are arranged in a honeycomb shape, and adjacent hole portions 18 are separated by partition walls 20 .

Here, the diameter and spacing of the holes in the porous film can be considered the width and spacing of multiple conductors (such as protruding electrodes, circuit patterns, etc.) to make sure.

In addition, from the viewpoint of ensuring insulation in the film surface direction and obtaining high connection reliability, it is preferable that the diameter of the hole portion is smaller than the narrowest interval of a plurality of conductors of the object to be connected, and the interval ratio of the hole portion is set by The plurality of conductors of the connector have a small narrowest width.

It is preferable that the diameter of the above-mentioned hole portion is set to 1/2 or less of the narrowest interval of a plurality of conductors that the object to be connected has, and the interval of the above-mentioned hole portion is set to 1/2 of the narrowest width of the plurality of conductors that the object to be connected has. /2 or less.

In addition, as shown in Fig. 2 (b), the diameter of the so-called hole portion refers to the value obtained by measuring the diameter R of the opening portion of the hole portion displayed on the film surface or the back surface, and the average value of the hole portion is measured at the interval of the hole portion. The distance L between the openings of the pores displayed on the surface or back of the film and the openings of adjacent pores is averaged. In addition, the above-mentioned diameter R and distance L can be measured from electron micrographs, optical micrographs, etc. of the surface of the porous membrane.

In addition, the thickness of the porous membrane can be determined in consideration of the mechanical strength, withstand voltage, and the like of the present ACF. It may be preferably in the range of 1 to 100 μm, more preferably 5 to 50 μm.

In addition, specific examples of polymers that form porous membranes include: polysulfone, polyethersulfone, polyphenylene sulfide, polyimide, polyamideimide, siloxane-modified polyimide, siloxane-modified Fluorine resins such as polyamideimide, polyetherimide, polyether ether ketone, polyester, polyamide, polytetrafluoroethylene, etc., can be used alone or in combination of two or more.

Among them, due to polysulfone, polyethersulfone, polyphenylene sulfide, polyimide, polyamideimide, siloxane-modified polyimide, siloxane-modified polyamideimide, poly Ether imide and polyetheretherketone are excellent in heat resistance and are suitable for use.

In this ACF, as shown in FIG. 3 , the conductive substance 14 is basically filled in the pores 18 of the porous membrane 12 . At this time, from the viewpoint of improving the electrical connection reliability in the film thickness direction, it is preferable that the conductive substance 14 has a protruding portion 24 slightly protruding out of the hole portion 18 .

In this case, the height of the protruding portion can be determined in consideration of the variation in the height of the conductor included in the connected portion. It may be preferably in the range of 0.1 to 10 μm, more preferably 1 to 5 μm.

In addition, the conductive substance is preferably composed of a group of conductive particles from the viewpoint of being easy to be uniformly filled into minute pores and having excellent conduction in the film thickness direction. In this case, the average diameter of electroconductive particle can be determined by the pore diameter of a porous membrane, etc. It is preferably about 1 μm or less.

Specific examples of the conductive particles include metal particles, resin-plated particles, carbon particles, and the like, and these may be used alone or in combination of two or more.

Among these electroconductive particles, metal particles can be suitably used. This is because the electrical resistance is small, and the melting point of the metal can be lowered by reducing the diameter of the particles, so fusion bonding is easy at low temperatures.

In this case, the metal particles specifically include, for example, Ag particles, Au particles, Pt particles, Ni particles, Cu particles, Pd particles, etc., and these particles may be one type or a mixture of two or more types. Since these metal particles are excellent in electrical conductivity, electrical conduction in the film thickness direction is easily obtained. Among these metal particles, Ag particles can be preferably suitably used.

Here, when using metal particles, resin-plated particles, or other particles containing metal at least on the particle surface as the conductive particles, it is preferable that groups of these particles filled in the holes are integrated by fusion bonding in the holes. The reason for this is that the gaps between these particles are reduced, the contact resistance is reduced, and the resistance in the film thickness direction is reduced. In addition, this is because the resistance in the film thickness direction becomes small because the organic substances and the like present between these particles can be removed by fusion bonding.

In addition, in the present ACF, the conductive substance may be filled in all the pores of the porous membrane, or a part of the pores not filled with the conductive substance may partially exist. That is, it is only necessary to fill at least one of the holes facing the conductors of the object to be connected with the conductive substance.

In the present ACF, as shown in FIG. 1 , adhesive layers 16 cover the front and back surfaces of porous membrane 12 in which holes 18 are filled with conductive substance 14 .

The thickness of the adhesive layer can be determined in consideration of the height of the conductors of the object to be connected, the interval between the conductors, and the like. It may be preferably in the range of 0.1 to 100 μm, more preferably 1 to 50 μm.

Here, as the adhesive layer material, any material having adhesiveness and insulating properties with the object to be connected can be used. Specific examples of suitable examples include prepregs in which thermosetting resins such as epoxy resins, unsaturated polyester resins, bismaleimide resins, and cyanate resins are in a semi-cured state. When the adhesive layer is a prepreg, the advantage is that the adhesive layer can be easily flowed out of the gap between the conductors of the object to be connected, and the adhesiveness with the object to be connected is also improved, and high reliability can be ensured. .

An epoxy resin can be suitably used as the above-mentioned thermosetting resin from the viewpoint of excellent adhesiveness with an object to be connected.

Next, a method of manufacturing the present ACF having the above-mentioned structure will be described. The manufacturing method of this ACF basically includes: the step of forming a porous membrane, the step of filling the pores of the porous membrane with a conductive substance, and the step of covering both sides of the porous membrane with an adhesive layer, or comprising: forming the pores filled with A step of making a porous membrane of a conductive substance and a step of coating both surfaces of the porous membrane with an adhesive layer.

(formation of porous film)

In the step of forming the porous membrane in the method for producing ACF, the following methods are basically suitably used. First, the outline and principle of the method will be described with reference to FIG. 4 . The method, in simple terms, refers to a method in which a polymer is dissolved in a volatile organic solvent that does not mix with water, and the support substrate on which the polymer solution is cast exists under high humidity conditions.

By this method, a porous membrane having many pores arranged in a honeycomb shape is spontaneously formed according to the following principle. That is, as shown in FIG. 4 , 1) water molecules in the air condense to form fine water droplets 26 due to the latent heat when the organic solvent volatilizes, and are densely filled on the surface of the polymer solution 28 . 2) The water drop 26 is transported to the interface between the polymer solution 28 and the support substrate 30 by further utilizing the convection and capillary force generated in the polymer solution 28 by latent heat. 3) The water droplet 26 is fixed on the support substrate 30 by the retreat of the organic solvent. 4) The water droplets 26 are further evaporated, and the porous membrane 12 having many pores 18 arranged in a honeycomb shape is formed using the regularly arranged water droplets 26 as a model. In addition, since the water droplet 26 forms a model, the inner wall surface 22 of the hole portion 18 is in a state of being curved outward.

Next, the method for producing the present ACF will be described in more detail. That is, a solution containing at least a hydrophobic and volatile organic solvent, a polymer soluble in the organic solvent, and an amphiphilic substance can be used as the polymer solution.

Examples of hydrophobic and volatile organic solvents include halides such as chloroform and methylene chloride; aromatic hydrocarbons such as benzene, toluene and xylene; esters such as ethyl acetate and butyl acetate; butanone (MEK), Ketones such as acetone, etc. These organic solvents may be used alone or in combination of two or more.

Polymers soluble in the above-mentioned organic solvents include, for example, polysulfone, polyethersulfone, polyphenylene sulfide, siloxane-modified polyimide, siloxane-modified polyamideimide, etc. The polymers can be used alone or in combination of two or more. In addition, when polyimide and polyamideimide are used, the purpose of modification with siloxane is to improve the solubility in the above-mentioned organic solvent.

Here, the above-mentioned amphiphilic substance is a so-called surfactant, and refers to a compound having both a hydrophobic portion and a hydrophilic portion. The amphiphilic substance is added mainly for the purpose of stabilizing the water droplet groups generated on the surface of the polymer solution, and the like. In addition, the stabilization of the water droplet group is presumed to be because the hydrophobic part of the amphiphilic substance is highly compatible with the hydrophobic organic solvent, and the space part of the resulting reverse micelles easily retains water.

Specific examples of such amphiphilic substances include: those having a hydrophilic acrylamide polymer as the main chain backbone, and simultaneously having dodecyl groups as hydrophobic side chains, and lactosyl or carboxyl groups as hydrophilic side chains. Polymers, or polyionic complexes of anionic polysaccharides such as heparin and dextran sulfate, and long-chain alkyl quaternary ammonium salts can be used alone or in combination of two or more.

In this case, the concentration of the polymer contained in the polymer solution is preferably within a range of 0.1 to 50% by weight, preferably 0.1 to 10% by weight.

This is because, if the polymer concentration is within this range, a porous membrane having sufficient mechanical strength can be obtained and a sufficient honeycomb structure can be obtained.

In addition, the addition amount of the amphiphilic substance contained in the polymer solution is preferably in the range of 0.01 to 20% by weight, preferably 0.05 to 10% by weight, based on the polymer.

This is because, when the amphiphilic substance is added within this range, a stable honeycomb structure can be obtained.

In the step of forming the porous membrane in the method for producing ACF, a polymer solution containing at least a hydrophobic and volatile organic solvent and an amphiphilic polymer may be used instead of the polymer solution described above.

Here, the term "amphiphilic polymer" refers to a polymer having both a hydrophobic portion and a hydrophilic portion.

Specific examples of such amphiphilic polymers include: polyether ether ketone, polyimide, polyamide amide, etc., with hydrophilic groups such as -SO ₃ H groups and -COOH groups introduced into the main chain and or side chains. Polyionic complexes of polymers such as imines and polyetherimides and cationic lipids; polyionic complexes of polyamic acid and cationic lipids, etc. These polymers can be used alone or in 2 A mixture of the above types is used.

The polyamic acid mentioned above means the resin composition obtainable by polymerizing tetracarboxylic dianhydride and a diamine compound in a polar solvent.

Examples of the above-mentioned polyamic acid include: 3,3',4,4'-biphenyl tetracarboxylic acid, 3,3',4,4'-biphenyl ether tetracarboxylic acid, 3,3',4,4' -biphenylsulfone tetracarboxylic acid, 3,3',4,4'-benzophenone tetracarboxylic acid, 2,2-di(3,4-dicarboxyphenyl)propane, 1,1,1,3 , 3,3-hexafluoro-2,2-bis(3,4-dicarboxyphenyl)propane, bis(3,4-dicarboxyphenyl)tetramethyldisiloxane, etc. Acids and their dianhydrides; cyclobutane tetracarboxylic acid, 1,2,3,4-cyclopentane tetracarboxylic acid, 2,3,4,5-tetrahydrofuran tetracarboxylic acid, 1,2,4,5- Alicyclic tetracarboxylic acid such as cyclohexanetetracarboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid Acids and their dianhydrides; pyromellitic acid, 2,3,6,7-naphthalene tetracarboxylic acid, 1,2,5,6-naphthalene tetracarboxylic acid, 1,4,5,8-naphthalene tetracarboxylic acid , 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic acid, 2,3,4,5-pyridine tetracarboxylic acid, 2,6-bis(3,4- Aromatic tetracarboxylic acids such as dicarboxyphenyl)pyridine and their dianhydrides; piromesate acid, trimellitic acid, and the like can be used alone or in combination of two or more.

In addition, examples of the above-mentioned diamine compounds include p-phenylenediamine, m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 4,4-diaminobiphenyl, 3,3'- Dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, diaminodiphenylmethane, diaminodiphenyl ether, 2,2' -Diaminodiphenylpropane, bis(3,5-dimethyl-4-aminophenyl)methane, diaminodiphenylsulfone, diaminobenzophenone, diaminonaphthalene, 1,4-bis(4- Aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene, 9,10-bis(4-aminophenyl)anthracene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)diphenylsulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-trifluoromethyl-4 , 4'-diaminobiphenyl, 4,4'-bis(4-diaminophenoxy) octafluorobiphenyl and other aromatic diamines; bis(4-aminocyclohexyl)methane, bis(4-amino- Alicyclic diamines such as 3-methylcyclohexyl)methane; aliphatic diamines such as tetramethylenediamine and hexamethylenediamine; diaminosiloxane, etc. These can be used alone or in combination of two or more use.

In addition, cationic lipids include, for example, aliphatic ammonium salt compounds having 4 or more carbon atoms, alicyclic ammonium salt compounds, and the like.

Specific examples include: salts of primary amines such as octylamine, decylamine, tetradecylamine, hexadecylamine, octadecylamine, behenylamine, and cyclohexylamine; dipentylamine, dihexylamine, dioctylamine, dioctylamine, Decylamine, two (tetradecyl) amine, two (hexadecyl) amine, two (octadecyl) amine, two (docosyl) amine, N-methyloctylamine, N-methyl n-decylamine , N-methyl n-tetradecylamine, N-methyl n-hexadecylamine, N-methyl n-octadecylamine, N-methyl n-eicosylamine, N-methyl n-dodecylamine, N-methyl Salts of secondary amines such as n-cyclohexylamine; N,N-dimethyloctylamine, N,N-dimethyln-decylamine, N,N-dimethyltetradecylamine, N,N-two Methyl n-hexadecylamine, N,N-dimethyl n-octadecylamine, N,N-dimethyl n-eicosylamine, N,N-dimethyl n-dodecylamine, N,N-dimethyl salts of tertiary amines such as n-cyclohexylamine; The salts of quaternary amines such as di(octadecyl)amine, dimethylbis(eicosyl)amine, dimethylbis(behenyl)amine, dimethyldicyclohexylamine, etc., these can be used alone or Mix 2 or more types.

The polyionic complex of the above-mentioned polyamic acid and cationic lipid can be prepared by adding a cationic lipid to a solution containing a substance obtained by neutralizing the polyamic acid with an alkali, or by mixing it in a compound that can be used for the above-mentioned polyamic acid. A solution of a cationic lipid dissolved in a polymerized organic solvent, etc. is obtained.

In addition, when using a polyionic complex of a polyamic acid and a cationic lipid, it is preferable to imidize the formed membrane by a known method. This is to form a porous film made of polyimide by ring-closing polyamic acid.

In the forming process of the porous membrane, when using a polymer solution containing at least a hydrophobic and volatile organic solvent and an amphiphilic polymer, it is preferable that the concentration of the amphiphilic polymer contained in the polymer solution is 0.1 to 50%. % by weight, preferably in the range of 0.1 to 10% by weight.

This is because, if the concentration of the amphiphilic polymer is within this range, a porous membrane having sufficient mechanical strength can be obtained, and also a sufficient honeycomb structure can be obtained.

In addition, since the hydrophobic and volatile organic solvents are the same as the above-mentioned organic solvents, description thereof will be omitted.

When forming the above-mentioned porous film, as the material of the support substrate for casting the above-mentioned polymer solution, for example, inorganic materials such as glass, metal, and silicon wafers; Molecular materials; water, liquid paraffin, etc.

In addition, the casting amount of the polymer solution can be appropriately adjusted so that the diameter of the pores of the porous membrane is smaller than the narrowest interval of a plurality of conductors of the object to be connected, and the interval of the holes is smaller than the plurality of conductors of the object to be connected. The narrowest width of the conductor is small, etc.

Specifically, the casting amount of the polymer solution is preferably within a range of 50 to 3500 μm, preferably 150 to 2000 μm, for a coating thickness.

In addition, it is preferable that the supporting substrate on which the polymer solution is cast exists in an atmosphere having a relative humidity of 50% to 95%. The reason for this is that when the relative humidity is lower than 50%, dew condensation may be insufficient, and when it exceeds 95%, it may be difficult to control the environment.

In addition, in the forming process of the above-mentioned porous membrane, the polymer solution may be cast on the support substrate in an atmosphere with a relative humidity of 50% to 95%, or the support substrate previously cast with the polymer solution may be placed Under an atmosphere with a relative humidity of 50% to 95%. In addition, air with a relative humidity of 50% to 95% can also be sprayed into the polymer solution.

In addition, in the forming step of the porous film, in order to promote the evaporation of the organic solvent and the evaporation of the water droplet group arranged on the surface of the polymer solution, heating, drying, etc. may be performed without affecting the formation of the porous film.

(Filling of conductive material)

Next, in the method for producing the present ACF, the method of filling the pores of the porous membrane with the conductive substance may be appropriately selected in consideration of the type and properties of the conductive substance to be used.

The method of filling the conductive substance includes, for example, a method in which a conductive substance is further contained in the above-mentioned polymer solution, and the like. That is, when the polymer solution used for producing the porous membrane also contains a conductive substance, a porous membrane filled with the conductive substance in its pores is spontaneously formed during the film formation process. Therefore, this method is advantageous in that it is unnecessary to refill the pores of the porous membrane with a conductive substance, so that the step of filling the pores of the porous membrane with a conductive substance can be omitted.

The content of the conductive substance in the polymer solution is preferably within a range of 1 to 52% by weight, preferably 1 to 10% by weight. In addition, it is preferable to use conductive particles having an average particle diameter of about 1 μm or less as the conductive substance.

Other filling methods of conductive substances include, for example, dispersing a conductive substance in a polymer-insoluble solvent, and immersing a porous membrane in the dispersion solution so that the conductive substance is adsorbed in the pores and slightly outside the pores. method etc. In this case, examples of the solvent include: alcohol solvents such as ethanol; water, ester solvents, amide solvents, hydrocarbon solvents, ketone solvents, ether solvents, and the like.

The content of the conductive substance in the dispersion solution is preferably within a range of 1 to 80% by weight, preferably 1 to 10% by weight. It is preferable to use conductive particles having an average particle diameter of about 1 μm or less as the conductive substance. In addition, the lifting speed and immersion time when lifting the porous membrane from the dispersion solution can be adjusted in various ways according to the pore diameter of the porous membrane, the content of the conductive substance in the dispersion solution, and the like.

In addition, for example, when metal particles are used as conductive particles, a porous film is placed on a glass substrate or the like surface-modified with an alkoxide of the same metal as the metal particles, and then immersed in a dispersion solution. , thereby selectively adsorbing the conductive particles inside the hole and a method slightly outside the inside of the hole, or the like.

In this case, the metal alkoxide to be used includes, for example, alkoxides of Cu, Ni, Ti, Fe, and the like.

Furthermore, for example, when metal particles are used as conductive particles, a metal film is pasted on one surface of the porous film, and after electroplating is performed using it as an electrode, the metal film is removed by etching, thereby making the metal particles selectively Methods such as depositing in the hole or slightly outside the hole.

(formation of bonding layer)

Next, in the production method of this ACF, the both sides of the porous membrane filled with the conductive substance in the pores are covered with adhesive layers, for example, the method of applying the adhesive layer material using a known coating means such as a coater And a method of laminating a prefabricated film-like adhesive layer, etc.

Next, how to use this ACF will be described using FIG. 5 . As shown in FIG. 5 , when the present ACF 10 is placed, for example, between a substrate 32 and a substrate 34, and hot pressing is performed for a short time at a temperature at which the adhesive layer 16 flows, the adhesive layer 16 is discharged by the flow, and at the same time, The conductive substance 14 is interposed between the electrode 36 of the substrate 32 and the electrode 38 of the substrate 34 . Then, when the resin is cured while maintaining this state, the electrodes 36 and 38 are electrically connected via the conductive substance 14 . On the other hand, the adjacent electrodes 36 ( 38 ) are electrically insulated by the adhesive layer 16 . Additionally, substrate 32 and substrate 34 are mechanically connected by curing of adhesive layer 16 .

The present invention is not limited to the above-described embodiments at all, and various changes can be made without departing from the spirit of the present invention.

Example

Next, the present invention will be described in detail using examples.

1. Production of the anisotropic conductive film of the embodiment

(Example 1)

To a solution obtained by dissolving polysulfone (manufactured by Aldrichichi, molecular weight Mw=56,000) in chloroform at a concentration of 0.1 [wt%], add dodecyl acrylamide and caproic acid at 10 [wt%] relative to polysulfone The copolymer is used as an amphiphilic substance and formulated into a polymer solution.

Then, the polymer solution was cast to a coating film thickness of 780 [μm] on a shallow pan (φ90 [mm]) continuously sprayed with air at a relative humidity of 50%, and the chloroform was volatilized. As a result, as shown in FIG. 6 , a porous membrane made of polysulfone was obtained which had many pores penetrating in the film thickness direction, the pores were arranged in a honeycomb shape, and the inner walls of the pores were curved outward. In addition, the pore diameter of the pores of the porous membrane was about 5 μm.

Then, the above-mentioned porous membrane was immersed in an Ag ethanol dispersion solution having a concentration of 3 [wt%] (manufactured by Nippon Paint, "Fainsufia SVE102", average particle diameter: 50 nm), and lifted at a speed of 5 [μm/sec]. As a result, as shown in FIG. 7 , a porous membrane filled with Ag particles in the pores was obtained. In addition, the filled Ag particles were melt-bonded by heating at 150° C. for 5 minutes.

Then, a bisphenol A type epoxy resin (manufactured by Epokisilene, "Epicoat 1001"), NBR (manufactured by Nippon Zesai, "Nipol 1072J"), an imidazole curing agent (manufactured by Shikoku Chemicals, , "キユゾゾル C11Z"), with bisphenol A epoxy resin: NBR: imidazole curing agent = 40:50:5 weight ratio, dissolved in a mixed solvent of MEK/THF = 50/50, to make it solid The composition was [30 wt %], and this solution was dried at 60° C. for 10 minutes to form an adhesive layer.

Then, the adhesive layer was laminated on both surfaces of the porous film filled with Ag particles in the pores to prepare the anisotropic conductive film of Example 1.

(Example 2)

Polysulfone was dissolved in chloroform at a concentration of 0.2 [wt%], and the coating film thickness was set to 1560 [μm]. In the same manner as in Example 1, the anisotropic conductive film of Example 2 was produced. membrane. The porous membrane made of polysulfone obtained when the anisotropic conductive membrane of Example 2 was produced, and the porous membrane filled with Ag particles in the pores are shown in FIGS. 8 and 9 , respectively. In addition, the pore diameter of the pores of the porous membrane was about 10 μm.

(Example 3)

Instead of polysulfone, siloxane-modified polyimide (manufactured by Ube Industries, "R15") was dissolved in chloroform at a concentration of 0.1 [wt%]. The anisotropic conductive film of Example 3 was produced in the same manner as in Example 1 except that the speed was set at 7 [μm/sec]. The porous film made of siloxane-modified polyimide and the porous film filled with Ag particles in the pores obtained when producing the anisotropic conductive film of Example 3 are shown in Fig. 10 and Fig. 11, respectively. . In addition, the pore diameter of the pores of the porous membrane was about 5 μm.

(Example 4)

Dissolve the siloxane-modified polyimide in chloroform at a concentration of 0.2 [wt%], set the coating film thickness to 1560 [μm], and compare the lifting speed after the porous film is immersed in the Ag ethanol dispersion solution The anisotropic conductive film of Example 4 was produced in the same manner as in Example 3 except that it was set to 5 [μm/sec]. The porous film made of siloxane-modified polyimide and the porous film filled with Ag particles in the pores obtained when producing the anisotropic conductive film of Example 4 are shown in Fig. 12 and Fig. 13, respectively. . In addition, the pore diameter of the pores of the porous membrane was about 13 μm.

(Example 5)

In N-methyl-2-pyrrolidone (NMP) 278g, make the polyamic acid of biphenyltetracarboxylic anhydride (BPDA) 29.4g (0.1mol) and diaminodiphenyl ether (DDE) 20.0g (0.1mol) in React at 23°C for 24 hours to prepare a polyamic acid solution. Then, this solution was poured slowly into 2 L of ethyl acetate, it was made to reprecipitate, it filtered, and it dried, and obtained the polyamic-acid powder 35.0g.

Then, 100 mg of this polyamic acid was heated and dissolved in water having a pH of 8. On the other hand, 200 mg of dimethyl di(octadecyl)ammonium bromide was dispersed in 200 mL of water by ultrasonic waves. Then, the above two solutions were mixed, allowed to return to room temperature and stirred overnight. Then, chloroform was added, and the chloroform phase was separated with a separatory funnel. Then, chloroform was concentrated with an evaporator, and reprecipitated with acetone. Then, centrifugation was carried out at 2600 rpm for 30 minutes with a centrifuge, and the solvent was dried (52.5 mg). Then, this polyionic complex solution was diluted to prepare a polymer solution having a concentration of 0.5 [wt%].

Then, the polymer solution was cast to a film thickness of 780 [μm] on a shallow pan (φ90 [mm]) blown with air at a relative humidity of 50% continuously, and the chloroform was volatilized. As a result, a precursor film composed of a polyimide precursor in which many pores penetrating in the film thickness direction are arranged in a honeycomb shape is obtained.

Then, the precursor film was immersed overnight in a solution of benzene: acetic anhydride: pyridine = 3:1:1 to imidize the polyionic complex. Thereby, a porous film made of polyimide was obtained, which had many pores penetrating in the film thickness direction, the pores were arranged in a honeycomb shape, and the inner walls of the pores were curved in the outward direction. At this point, cationic lipids were removed by rinsing with ethanol. In addition, the pore diameter of the pores of the porous membrane was about 4 μm.

Then, the above-mentioned porous membrane was immersed in an Ag ethanol dispersion solution having a concentration of 3 [wt%] (manufactured by Japan Peinto, "Fainsufia SVE102", average particle diameter: 50 nm), and lifted at a speed of 5 [μm/sec]. As a result, a porous membrane in which the Ag particles were filled in the pores was obtained. In addition, the filled Ag particles were melt-bonded by heating at 150° C. for 5 minutes.

Then, the above-mentioned bisphenol A type epoxy resin, NBR, and imidazole curing agent are dissolved in MEK/THF=50/ In a mixed solvent of 50, the solid content was 30 [wt%], and the solution was dried at 60° C. for 10 minutes to form an adhesive layer.

Then, the anisotropic conductive film of Example 5 was obtained by laminating the adhesive layer on both surfaces of the porous film in which the Ag particles were filled in the pores.

(Example 6)

Dilute the obtained polyionic complex solution, prepare a polymer solution with a concentration of 0.7 [wt%], and set the coating film thickness to 1560 [μm], except that, operate in the same manner as in Example 5, and make Anisotropic conductive film of Example 6. The pore diameter of the pores of the porous film made of polyimide obtained when producing the anisotropic conductive film of Example 6 was about 8 μm.

2. Evaluation of anisotropic conductivity

The evaluation of the electrical conductivity in the film thickness direction was performed as follows. That is, one surface of the anisotropic conductive film of Examples 1 to 6 is temporarily crimped to comb-shaped electrodes 40 having a predetermined pitch P as shown in FIG. material 44 mutually insulated comb-shaped electrodes). Then, as shown in FIG. 15( a), the anisotropic conductive film 10 temporarily crimped with the comb-shaped electrode 40 is respectively installed so that the other surface is in contact with the copper plate 48 laminated on the glass plate 46 and heated at 170° C. × 20 seconds for real crimping.

Then, the tester 50 was used to evaluate the electrical conductivity of the thus obtained samples A ₁ to A ₆ (the foot code of A corresponds to the number of each example). In addition, in this evaluation, for the anisotropic conductive films of Example 1, Example 3, and Example 5, the pitch P of the comb-shaped electrodes 40 was set to 30 μm, and for the anisotropic conductive films of Example 2, Example 4, and Example 6 The anisotropic conductive film is used, and the pitch of the comb-shaped electrodes is set to P=100 μm.

As a result of this evaluation, it was confirmed that the resistance values between the comb-shaped electrodes were all 0 [Ω] for the samples A ₁ to A ₆ .

(2) Evaluation of insulation performance in the film surface direction

The evaluation of the insulation performance in the film plane direction was performed as follows. That is, one surface of the anisotropic conductive film of Examples 1 to 6 was temporarily pressure-bonded to the same comb-shaped electrode 40 as above. Then, as shown in FIG. 15( b ), the anisotropic conductive film 10 temporarily press-bonded with the comb-shaped electrode 40 is installed so that the other surface is in contact with the glass plate 46, and the actual pressure-bonding is performed at 170° C. for 20 seconds. .

Then, the tester 50 was used to evaluate the insulation properties of the samples B ₁ to B ₆ thus obtained (the foot code of B corresponds to the number of each example). In addition, the pitch P of the comb-shaped electrode in this evaluation was set similarly to the above.

As a result of this evaluation, it was confirmed that the resistance values between the comb-shaped electrodes were all 10 ⁸ [Ω] or more in the samples B ₁ to B ₆ .

From these evaluation results, it was confirmed that the anisotropic conductive film of this example has sufficient anisotropic conductivity.

Claims (22)

1. anisotropic conductive film is characterized in that having:

By the perforated membrane that macromolecule constitutes, this film has in the many holes portion that film thickness direction runs through, and described hole portion is arranged in cellular, the internal face direction bending laterally of simultaneously described hole portion;

Conductive material, it is filled in the described hole portion of this perforated membrane; With

Tack coat, it is overlayed on the two sides of described perforated membrane.

2. anisotropic conductive film as claimed in claim 1, it is characterized in that described macromolecule is by being selected from constituting more than a kind or 2 kinds in polysulfones, polyether sulfone, polyphenylene sulfide, polyimides, polyamidoimide, silicone-modified polyimides, silicone-modified polyamidoimide, Polyetherimide and the polyether-ether-ketone.

3. anisotropic conductive film as claimed in claim 1, it is characterized in that, described perforated membrane be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent, the macromolecule that dissolves in this organic solvent and amphiphilic materials.

4. anisotropic conductive film as claimed in claim 1, it is characterized in that, described perforated membrane and described conductive material be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent, the macromolecule that dissolves in this organic solvent, amphiphilic materials and conductive material.

5. as claim 3 or 4 described anisotropic conductive film, it is characterized in that, the described macromolecule that dissolves in the organic solvent be selected from polysulfones, polyether sulfone, polyphenylene sulfide, silicone-modified polyimides and the silicone-modified polyamidoimide more than a kind or 2 kinds.

6. anisotropic conductive film as claimed in claim 1, it is characterized in that, described perforated membrane be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent and amphipathy macromolecule.

7. anisotropic conductive film as claimed in claim 1, it is characterized in that, described perforated membrane and aforementioned conductive material be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent, amphipathy macromolecule and conductive material.

8. as claim 6 or 7 described anisotropic conductive film, it is characterized in that described amphipathy macromolecule is to have introduced the macromolecule of hydrophily base and the polyion complex compound of cationic lipid on main chain and/or side chain.

9. as claim 6 or 7 described anisotropic conductive film, it is characterized in that described amphipathy macromolecule is the polyion complex compound of polyamic acid and cationic lipid, described perforated membrane has carried out the imidizate processing after film forms.

10. as each described anisotropic conductive film of claim 1～9, it is characterized in that the diameter of described hole portion is littler than the narrowest interval that is connected a plurality of conductors that thing has, and the interval of described hole portion is littler than the narrowest width of described conductor.

11., it is characterized in that described conductive material is made of the group of electroconductive particle as each described anisotropic conductive film of claim 1～10.

12. anisotropic conductive film as claimed in claim 11 is characterized in that, described electroconductive particle is a metallic.

13. anisotropic conductive film as claimed in claim 12 is characterized in that, described metal is by being selected from constituting more than a kind or 2 kinds among Ag, Au, Pt, Ni, Cu and the Pd.

14., it is characterized in that the group of the described metallic of filling in the portion of described hole forms one by adhere as claim 12 or 13 described anisotropic conductive film.

15., it is characterized in that described tack coat is the prepreg that thermosetting resin is in semi-cured state as each described anisotropic conductive film of claim 1～14.

16. anisotropic conductive film as claimed in claim 15 is characterized in that, described thermosetting resin is an epoxy resin.

17. an anisotropic conductive film manufacture method is characterized in that, comprises:

The operation of the perforated membrane that formation is made of macromolecule, described perforated membrane have in the many holes portion that film thickness direction runs through, and described hole portion is arranged in cellular, the internal face direction bending laterally of simultaneously described hole portion;

The operation of filled conductive material in the portion of the hole of described perforated membrane; With

Operation at the two sides of described perforated membrane lining tack coat.

18. anisotropic conductive film manufacture method as claimed in claim 17, it is characterized in that, described perforated membrane be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent, the macromolecule that dissolves in this organic solvent and amphiphilic materials.

19. anisotropic conductive film manufacture method as claimed in claim 17, it is characterized in that, described perforated membrane be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent and amphipathy macromolecule.

20. an anisotropic conductive film manufacture method is characterized in that, comprises:

The operation of the perforated membrane that formation is made of macromolecule, described perforated membrane have in the many holes portion that film thickness direction runs through, and described hole portion is arranged in cellular, and the internal face direction bending laterally of simultaneously described hole portion is filled with conductive material in the portion of described hole; With

Operation at the two sides of aforementioned perforated membrane lining tack coat.

21. anisotropic conductive film manufacture method as claimed in claim 20, it is characterized in that, described perforated membrane be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent, the macromolecule that dissolves in this organic solvent, amphiphilic materials and conductive material.

22. the manufacture method of anisotropic conductive film as claimed in claim 20, it is characterized in that, described perforated membrane be by make curtain coating the support substrate of Polymer Solution be present in the atmosphere of relative humidity more than 50% and form, wherein, described Polymer Solution comprises at least: have hydrophobicity and volatile organic solvent, amphipathy macromolecule and conductive material.

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