JPH07302666A - Manufacture of anisotropic conductive resin film-like mold - Google Patents

Abstract

PURPOSE:To electrically connect a highly fine electrode held between fine electrodes facing each other. CONSTITUTION:Conductive particles are uniformly dispersed in the surface direction of a film-like mold, thus an anisotropic conductive resin film-like mold having conductivity only in the thickness direction of the film-like mold via the conductive particles exposed at the obverse and reverse is manufactured. In this manufacturing method, the conductive particles 1 are adhesively bonded to the surface of an adhesive 2, and a film forming resin 10 insoluble with the adhesive 2 is filled between the conductive particles 1. Consequently, the film forming resin 10 is dried or hardened, followed by peeling the adhesive 2 from the film forming resin 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an anisotropically conductive resin film-shaped molded product having conductivity only in the thickness direction through conductive particles exposed on the front and back of the resin film-shaped molded product. It is a thing.

[0002]

2. Description of the Related Art As electronic parts have become smaller and thinner, circuits used therein have become higher in density and higher in definition. Since it is difficult to connect these fine circuits with conventional solder, rubber connectors, etc., recently, a connecting member made of an anisotropic conductive adhesive or a film-like material has been widely used. In this method, an electrical connection member layer made of an insulating resin containing a predetermined amount of a conductive material is provided between opposing circuits, and pressure or heating / pressurizing means is provided to electrically connect the upper and lower circuits. Simultaneously with the connection, insulation is provided between adjacent circuits. In addition, using the insulating resin as an adhesive,
There is also used a structure in which electrical connection between circuits facing each other and adhesive bonding between circuits are performed at the same time.

As prior art documents relating to such an anisotropically conductive resin film-shaped molded product having conductivity only in the thickness direction, for example, as disclosed in Japanese Patent Laid-Open No. 51-21192, A mixture in which conductive particles are held in a state where they are not in contact with each other by a non-conductive base is molded into a sheet having a thickness approximately equal to the size of the conductive particles, and only in the thickness direction of the sheet through the conductive particles. It has a conductive structure or a homogeneous mixture with a flexible insulating binder containing 20 to 0.05% by volume of conductive particles as disclosed in Japanese Patent Publication No. 59-31190. There is a sheet-shaped one-piece electrical connector.

These resin film-shaped molded products are molded by a method in which conductive particles are uniformly dispersed in a resin and rolled by a roll or the like to obtain a molded product having a desired thickness, or a conductive resin in a liquid resin. A uniform dispersion of the functional particles is cast by a bar coater or the like with a constant thickness, and then dried or cured to obtain a molded product having a desired thickness. When an anisotropic conductive resin film-shaped molded product having conductivity only in the thickness direction is sandwiched between circuits and the connection between circuits is obtained in a contact state by pressurization, individual conductive materials are used to reduce connection resistance. It is effective to expose the hydrophilic particles on both sides of the film. As a method of exposing the conductive particles on both sides of the film, a method of rolling the film with a roll or the like as disclosed in JP-A-61-23507 and JP-A-61-188818,
As disclosed in JP-A-61-200616, there is a method of using rolling and sputter etching together.

Further, as disclosed in Japanese Patent Application Laid-Open No. 5-74512, a method in which conductive particles are put into a film having through holes and then the film and the conductive particles are fixed,
-239578, the conductive particles as described in
A method of filling a liquid resin between flat plates in a state of being sandwiched by a single flat plate to form a film, and as described in JP-A-2-117980 and JP-A-5-67480, conductive particles are added. There is also a method of embedding it in a film-shaped resin. In addition, the surface layer of the film-forming resin on both sides is dissolved or decomposed and removed with a solvent, or the sputter etching, plasma etching,
A method of physically decomposing and removing using an excimer laser or the like is known. In this anisotropically conductive resin film-shaped molded product having conductivity only in the thickness direction, in order to increase the number of conductive points per unit area of the film and achieve high resolution, the amount of the conductive particles blended in the film Need to increase.

[0006]

However, in the above-mentioned manufacturing method by rolling according to the prior art, the particle size of the conductive particles is reduced in order to correspond to the high-definition electrode, and the film thickness is thin and uniform, for example, to several tens of μm or less. However, there is a problem in that if the particle diameter of the conductive particles varies, the film thickness also varies. Further, rather than the above rolling method, in the method of casting a uniform mixture of a liquid resin and conductive particles which is currently generally adopted to form a film, in order to correspond to a high-definition electrode, When the blending amount is increased, the viscosity of the liquid resin in which the conductive particles are dispersed increases and the fluidity is impaired, so that it becomes difficult to cast the conductive resin with a constant thickness by a bar coater or the like. There is no choice but to reduce the blending amount of.

There is also a method of increasing the casting thickness and increasing the particle filling layer of the lower layer of the resin film-shaped molded product by sedimentation of the conductive particles, but it is possible to avoid forming the conductive particles into a multi-layer structure. However, the number of particles that do not contribute to electrical conduction in the thickness direction increases. Further, in this method, the resin layer that must be removed later is thick, and it becomes difficult to uniformly expose the particles to the film surface. In the method of adhering and fixing the film and the conductive particles after the conductive particles are put into the film provided with the through holes, it is difficult to provide many fine holes in the film in terms of productivity and cost. is there. In the method of filling the liquid resin between the flat plates with the conductive particles sandwiched between the two flat plates to form a film, in order to fill the liquid resin between the minute flat plates, the viscosity of the resin must be extremely small. However, if the particle size of the conductive particles varies, the conductive particles may flow out.

In the method of embedding the conductive particles in the film-shaped resin, the resin cannot be sufficiently wetted on the surface of the conductive particles unless the viscosity of the resin is sufficiently low such that the resin is in a liquid state. Adhesiveness with is inferior, and conductive particles are likely to fall off. When a liquid film-shaped resin is used, it is inevitable that the resin adheres to the support in the step of transferring the conductive particles held on the support to the liquid resin surface, which makes it difficult to form a film. Also, when the filling amount of the conductive particles is increased, it becomes difficult to fill the resin in the voids between the conductive particles without excess or deficiency, and the filling amount of the conductive particles and the film before filling the conductive particles The relationship with the thickness of the foamed resin must be strictly specified. If the thickness of the film-shaped resin is thick, the adhesion of the resin to the above-mentioned support cannot be avoided, and if it is thin, the strength as a film cannot be obtained,
Particles fall out. The present invention has been made in view of such circumstances, and an object thereof is to provide a novel method for producing an anisotropically conductive resin film-shaped molded article, which enables electrical connection even with fine electrodes.

[0009]

The present invention is to uniformly disperse conductive particles in the surface direction of a film-shaped molded product, and to conduct the conductive film only in the thickness direction of the film-shaped molded product through the exposed conductive particles on the front and back. In the method for producing an anisotropically conductive resin film-shaped molded product, the conductive particles are adhesively fixed to the surface of the adhesive material, and a film-forming resin incompatible with the adhesive material is filled between the conductive particles. The present invention relates to a method for producing an anisotropically conductive resin film-shaped molded product, which comprises removing an adhesive from the film-forming resin after drying or curing the film-forming resin. That is, by spraying the conductive particles on the pressure-sensitive adhesive surface, after fixing the conductive particles on the pressure-sensitive adhesive surface in the state of being arranged in the plane direction, a step of applying a film-forming resin to fill the space between the conductive particles is performed. Have. Then, the film-forming resin is dried or cured, and if necessary, the film-forming resin on the particles is removed to obtain a resin film-shaped molded product having conductivity only in the thickness direction of the film.

In the present invention, a film or a net having a through hole (hereinafter, this jig is referred to as a mask) is placed on the surface of the adhesive material, and the conductive particles are dispersed (claim 2) to obtain a transparent film. The conductive particles can be attached only to the surface of the adhesive material in the holes, and the insulating property in the plane direction of the film can be controlled. For example, if the size of the through holes is such that two or more conductive particles do not adhere to the surface of the pressure-sensitive adhesive material, an anisotropic conductive resin film-shaped molded product in which the insulating property is maintained between the individual particles can be obtained. Further, after spraying the conductive particles on the pressure-sensitive adhesive surface, the conductive particles are pressed against the pressure-sensitive adhesive surface using a rubber roll or the like (claim 3) to improve the array density of the conductive particles in the surface direction, and It is possible to improve the conductivity in the thickness direction of the film. By embedding the conductive particles in the pressure-sensitive adhesive layer by adjusting the pressure applied during this pressing (Claim 4), it is possible to form a structure in which the conductive particles are projected from the surface of the resin film-formed product, and the electrical The connectivity can be improved.

As a method of fixing the conductive particles to the surface of the adhesive material, the conductive particles are held on a charged body such as a roll by static electricity, and then the charged body is pressed against the surface of the adhesive material to adhere the conductive particles. By transferring to the material surface (Claim 5), it is possible to continuously arrange a certain amount of conductive particles having a small amount of surplus particles that do not adhere to the adhesive material layer. At this time, by placing a mask on the charged body and spraying the conductive particles (Claim 6), the conductive particles can be attached only to the surface of the charged body in the through-hole, and the surface direction of the film can be improved. Insulation can be controlled. Also, in a method in which the conductive particles and the adhesive material surface are charged with different charges, and the conductive particles are adsorbed on the adhesive material surface and then fixed (claim 7), a certain amount of conductive particles with few surplus particles are continuously added. It becomes possible to arrange in. Also in this case, by placing the mask on the adhesive material body and spraying the conductive particles, the conductive particles can be attached only to the adhesive material surface in the through hole, and the insulating property in the plane direction of the film can be obtained. Can be controlled.

In the method of fixing the conductive particles to the surface of the adhesive material by electrostatic force, a fibrous conductor is used in place of the conductive particles (claim 8), whereby the length of the fiber is perpendicular to the film surface. An anisotropic conductive resin film-shaped molded product in which the shafts are arranged can be formed, and the conductive material can be packed at a high density to improve the conductivity. In addition, by using conductive particles or fibrous conductors whose surface is previously coated with an electrically insulating layer such as a thermoplastic resin that can be removed by heating or pressing (claim 9), these are finely distributed in the plane direction of the film. Even in the state of being filled in, it becomes possible to maintain the insulating property in the surface direction.

In an anisotropically conductive resin film-like molded product using conductive particles or fibrous conductors whose surface is previously coated with this electrically insulating layer, a part of the front surface and the back surface of the film is etched with a solvent or polished. The thickness of the film is made equal to or less than the particle diameter of the conductive particles or the fiber length of the fibrous conductor, and the conductive particles or fibrous conductor exposed on the front surface and the back surface of the film are removed. By removing the electrically insulating layer and contacting the electrodes with the front and back surfaces of the film (claim 10), it is possible to obtain an anisotropic conductive resin film-like molded product capable of conducting electricity between the electrodes. Use of a thermoplastic resin that melts or softens a film-forming resin by heat and pressure, an uncured thermosetting resin, or a resin that cures by light energy such as ultraviolet rays or electron beams (claim 1
According to 1), after electrical connection is obtained with particles protruding on the film surface, the conductive particles between the electrodes are deformed by pressurization, or the film-forming resin is bonded with the conductive particles embedded in the electrodes. As a result, it is possible to connect and fix the electrodes.

The type of conductive particles used in the present invention is not particularly limited, and particles of metal particles or particles of glass, ceramics, plastics or the like having a metal plating layer formed on the surface thereof may be used alone or in combination. Can be used.
It is also possible to use one in which each individual conductive particle is composed of an aggregate of conductive particles having a small particle diameter. The particle size is selected according to the fineness of the circuit to be connected, but the particle size of each particle needs to be as uniform as possible. The shape is preferably a spherical shape in order to make the size of the particles uniform for connecting fine electrodes, but it is preferable that the surface has irregularities in terms of adhesiveness to the film. Generally, when connecting very fine electrodes, use particles with a metal plating layer formed on the surface of spherical plastic particles, and when using metal particles for heat resistance, etc., use a gas atomizing method that is closer to a spherical shape or rotation. It is preferable to use particles produced by the electrode atomizing method. However,
Even irregularly shaped particles such as metal powder produced by the water atomizing method can be used as conductive particles by making the particle sizes uniform by classification.

Further, the fibrous conductor used in the present invention has a shape having a long axis and is not affected by the manufacturing method. That is, it can be said that the fibrous conductor has the major axis of the conductive particles. The type of the fibrous conductor is not particularly limited, but generally commercially available metal short fibers, glass fibers having the surface thereof plated with metal, carbon fibers, or the like can be used. The diameter and length of the fiber are selected according to the fineness of the electrodes to be connected, but the uniform fiber length provides better conductivity, and the smaller fiber diameter and uniform size are used for finer electrodes. You can Further, in the case where a mask for controlling the fixing position of the conductive particles is not used, in order to secure the insulative property in the surface direction, the amount of the conductive particles or the fibrous conductor to be spread on the adhesive material surface must be appropriate. I won't. The conductive particles and the fibrous conductors contact each other more and the insulating property in the plane direction is impaired.
Therefore, a high-density conductive point can be obtained by providing an electrically insulating layer (insulating layer) on the surface of each conductive particle or fibrous conductor.

The insulating layer contains a resin that is incompatible with the film-forming resin and can have a single-layer structure or a multi-layer structure.
Here, “not compatible” means that the mutual resins do not have an affinity and do not form a homogenized admixture, and there is an SP value as a commonly used measure of compatibility (solubility parameter: As described in Adhesion Handbook, 2nd Edition, page 46) edited by the association), the farther the SP value is, the less compatible the resins are, and resins having a difference of 1.0 or more are less likely to be compatible with each other. Further, the fact that the resins have different heat melting temperatures or heat softening temperatures from each other is also one condition that does not form a homogenized admixture of the resins. It is difficult to form a homogenized mixture. These criteria differ slightly for each material, so individual examination is necessary. It is important to note that when a film is made by coating, the film-forming resin is generally dissolved and diluted with a suitable solvent, and a solution with an appropriate viscosity is cast, so the insulating layer is used when making this film. It is to use a resin that does not dissolve in the solvent used or the liquid component in the film-forming resin, that is, does not dissolve in the film-forming resin solution.

If the resins are incompatible with each other, it is possible to provide an insulating layer which is insoluble in the film-forming resin solution by selecting an appropriate solvent. Specifically, thermoplastic polyurethane, soluble nylon, epoxy resin,
A phenoxy resin, polyethylene, polyester, or the like is used, and a resin that does not dissolve in the film-forming resin solution and that can easily form an insulating layer is selected from these. These criteria differ slightly for each material, so individual examination is necessary. The optimum thickness of the insulating layer varies depending on whether the resin is resistant to dissolution in a film-forming resin solution and whether the coating of fine conductive particles is sufficient.
10 μm is suitable. The method for forming the insulating layer includes a wet method in which a resin is dissolved in a solvent and applied on the surface of the conductive particles in a solution state, and then dried, or a resin powder for forming the insulating layer and the conductive particles are collided at high speed. It can be formed by a dry method such as mixing, mixing and rubbing, melting and adhering.

In the wet method, the resin must be dissolved in a suitable solvent, but it is easy to form the insulating layer to a desired thickness, and in particular, it has the advantage that a thin insulating layer of 1 μm or less can be easily formed. is there. The dry method has an advantage that an insulating layer can be formed even with a resin that is difficult to dissolve in a solvent, and is suitable for forming a thick insulating layer having a thickness of 1 μm or more. The method of forming an aggregate in which fine conductive particles are dispersed in these insulating layers is, for example, a wet method in which fine conductive particles are dispersed in a resin solution forming an insulating layer and applied to the surface of the conductive particles. In the dry method, the resin powder that forms the insulating layer, minute conductive particles and conductive particles are made to collide at high speed, mixed and rubbed, melted and adhered, There is a method of embedding fine conductive particles in the. Alternatively, a method of embedding the fine conductive particles in the insulating layer by treating the insulating coated conductive particles and the fine conductive particles having the insulating layer formed by the wet method in advance by the dry method can be adopted.

Due to its adhesiveness, the adhesive material should be held so that the conductive particles do not move when it is handled after the particles are sprayed or when the film-forming resin is applied. Not what you need. Generally, if the contact area between the conductive particle surface and the adhesive material is large, the holding force of the conductive particle is large, so a soft substance that can fill the irregularities of the conductive particle surface at the time of spraying the conductive particle can be used. For example, it can be used as an adhesive material. That is, when handling after coating the conductive particles or when applying the film-forming resin, the substance that holds the conductive particles so that the conductive particles do not move due to the adhesive force between the conductive particles and the adhesive material, It can be an adhesive material.

Specifically, SBR, polyisobutylene, polybutene, natural rubber, neoprene, butyl rubber, and other rubbers, and resins having a glass transition temperature of room temperature or lower, such as acrylic resins, silicone resins, and fluororesins, are used as the adhesive material. Can be done. Further, it is also possible to use a resin having tackiness by mixing a tackifier such as a terpene resin or an indene resin with these resins or a non-tacky resin. Further, these resins may have a network structure by cross-linking in order to reduce compatibility with the film-forming resin. The adhesive material shown above is a film or plate as a base material,
By applying it on a roll etc. as a composite structure,
Easy to handle. Generally PET, polyethylene,
A film such as polypropylene can be used as a substrate.

The film-forming resin acts as a binder for the conductive particles and can be formed into a film. Also, in order to prevent the conductive particles from migrating by dissolving the adhesive material that adheres and fixes the conductive particles when applying the film forming resin, the film forming resin that is incompatible with the adhesive material is selected. To do. Specifically, in addition to various solvent-soluble synthetic resins and elastomers, thermoplastic resins such as polyethylene, vinyl acetate, polypropylene, and resins with high heat resistance such as polyether sulfone, polyether imide, and polyimide, and epoxy resins. A thermosetting resin such as a phenol resin, a photocurable resin such as a urethane acrylate having an acryloyl group, or an epoxy acrylate can be used. As a combination of the film-forming resin and the adhesive material which are incompatible with each other, S such as polyisobutylene is used.
An adhesive material having a small P value and a resin having a large SP value such as polyamic acid which is a substance before curing of polyimide can be used as the film forming resin.

Further, since silicone resin and fluorine resin are incompatible with many other resins, many resins can be selected as the film-forming resin by selecting these resins as the adhesive material. Also, when the anisotropic conductive resin film-shaped molded product of the present invention is used for both the purpose of both electrical connection between electrodes and adhesion between electrodes, each of the above film-forming resins is used and pressure is applied between the electrodes. While heating or irradiating light while flowing, the film-forming resin is allowed to flow between the electrodes and then cured. At this time, among these film-forming resins, the thermosetting resin is excellent in heat resistance because it forms a network structure and is cured by the heat and pressure during circuit connection, and thus high connection reliability can be obtained. It is preferably used as part of the forming resin. The thickness of the resin film-shaped molded product is not particularly limited, but as described above, it becomes unsuitable for connection of fine circuits since the particle size of the conductive particles to be used becomes large and the resolution deteriorates as the thickness increases. Further, when the thickness becomes thinner, the handling is not easy, and the production becomes difficult due to the generation of wrinkles and the like, so 0.005 to 1 mm is suitable.

As the mask, there are a net-shaped one woven from fibers such as silk, nylon and stainless steel, and a so-called ordinary metal mask in which a thin plate of stainless steel or nickel is formed with a through hole at a desired position or size by etching or the like. Used.
These masks are used by placing them on an adhesive material or a charged body.However, when spraying conductive particles by electrostatic force, the chargeability of the mask is controlled by selecting the mask material or grounding. It is desirable that the conductive particles be arranged only in the through holes of the mask. However, even if the charging potential of the mask is non-uniform on the mask surface and conductive particles adhere to the mask, the electrostatic adhesion between the mask and the conductive particles can be adjusted to reduce the conductivity of the mask. The particles can be removed by a resin blade or the like. For example, even non-conductive mesh such as nylon,
The net used for a sieve or the like is generally subjected to antistatic treatment and is useful for preventing particles from adhering to the mask. The size of the through hole of the mask may be a size that allows the conductive particles to pass therethrough, or a size that does not allow the conductive particles to pass.

What is necessary is that the conductive particles are arranged at the positions of the through holes of the mask, and at this time, a part of the conductive particles come into contact with the adhesive material or the charged body and are fixed by the adhesive force or the electrostatic force. That is. For example, a mask is placed on the adhesive surface, conductive particles are sprayed to fix the conductive particles to the through holes of the mask, and then a film-forming resin is applied without removing the mask to form an anisotropic conductive resin. A film-shaped molded product can be obtained. The mask can be repeatedly used by peeling the mask from the film-forming resin surface of the obtained anisotropically conductive resin film-shaped molded product. At this time, since the conductive particles do not pass through the through holes of the mask, the particle size of the conductive particles may be larger than that of the through holes of the mask. Also, when the mask is placed on the charged body and the conductive particles are placed at the positions of the through holes of the mask by electrostatic force and then transferred by pressing on the adhesive surface, the mask is placed after the conductive particles are placed. Since it is not necessary to remove, the particle size of the conductive particles may be larger than that of the through hole of the mask.

As a method of charging by static electricity, a method of using a corona charging device is generally used, and the object of the present invention is also achieved by this device. This device can charge an object in a non-contact manner, and can control it to a desired constant value while monitoring the amount of charge. In addition, it is possible to charge by a contact charging method or the like in which a voltage is applied to a conductive roller or brush to bring it into contact with an object. The charging may be carried out on a necessary member such as a charging body, an adhesive material, a mask or the like on which the conductive particles are scattered, as long as the potential difference from the conductive particles is a value sufficient to move and adsorb the conductive particles. .

At this time, conversely, a method of charging the conductive particles may be considered, but the conductive particles may scatter due to the repulsion due to the electrostatic force between the conductive particles, or the charge amount may vary among the individual conductive particles. However, there is a problem that the amount becomes large and the adhered amount varies within the surface, so caution is required. The charge amount is usually several hundred volts or more, and the object of the present invention can be achieved. The charged body may be any substance that is charged to a different charge from the conductive particles by the charging device, and generally, electrically insulating resins such as polyethylene, nylon and polyester can be widely used. In addition, even a conductive metal or the like can be used as a charging body by directly applying a voltage or preventing leakage of charges by an insulator.

When the anisotropically conductive resin film-shaped molded product of the present invention is used as a connecting material for a circuit, for example, the molded product of the present invention is inserted between the circuits to be connected, and pressure is applied. Can be reached. To use it as a permanent connection material, fix the electrodes with pressure applied by a pressure jig, fill with a liquid adhesive under pressure to bond them, or heat under pressure. Alternatively, a method of curing the film-forming resin by light irradiation and using the film-forming resin as an adhesive is possible. Further, the resin film-shaped molded product of the present invention can be applied not only to the above-mentioned circuit connecting material but also to a switch member, a multilayer circuit member and the like.

FIG. 1 shows the manufacturing sequence of the anisotropically conductive resin film-shaped molded product of the present invention. First Figure 1
As shown in (a), a layer of the pressure-sensitive adhesive material 2 is provided on the base film 3 which is a support made of a resin film or the like by coating such as solution coating, and then as shown in FIG. 1 (b). Then, the conductive particles 1 are scattered on the pressure-sensitive adhesive layer, and the conductive particles 1 are held by the adhesive force of the pressure-sensitive adhesive 2. Then Figure 1
As shown in (c), the film forming resin solution 14 is filled between the conductive particles by coating. At this time, since the conductive particles 1 are fixed on the adhesive material 2, they do not move in the film-forming resin solution 14, the particles do not aggregate during coating, and the particles are evenly distributed on the surface. Holds the arranged state. Next, as shown in FIG. 1D, after the film-forming resin 10 is dried or cured, the film-forming resin 10 covering the conductive particles 1 is dissolved or physically removed. ), The conductive particles 1 are exposed on the surface of the film 3. After that, the film-forming resin 10 is peeled from the interface with the adhesive material 2 to obtain an anisotropic conductive resin film-shaped molded product as shown in FIG.

Since the film forming resin 10 and the adhesive material 2 are incompatible with each other, they can be easily peeled from the interface. Also,
Since the conductive particles are in contact with the adhesive layer, the conductive particles 1 can be exposed on the release surface of the film forming resin 10, and the portion of the film forming resin 10 for exposing the conductive particles 1 Removal is performed on one side of the film 3 (Fig. 1
It may be performed only for the film-forming resin coated surface of (d). At this time, since the conductive particles 1 are supported by the base film 3 and the adhesive material 2, the film forming resin 1
It is possible to prevent the film-forming resin layer from being damaged, extended, and the conductive particles falling off in the partial removal step of 0. Further, even if the adhesive material 2 and the base material film 3 have a low adhesion and are peeled off at the interface with the base material film due to the structure in which they are adhered to the film forming resin 10, the film forming resin and the adhesive material are incompatible. Therefore, by selecting an appropriate solvent, only the adhesive material can be dissolved and removed, and a desired anisotropically conductive resin film-shaped molded product can be obtained.

FIG. 2 (a) shows a state in which the anisotropic conductive resin film-shaped molded product of the present invention is inserted between the circuits 11 and pressed to make electrical connection. FIG. 2B shows a circuit 11 of an anisotropically conductive resin film-shaped molded product obtained by a conventional manufacturing method.
It shows a state in which it is inserted between and pressurized to make an electrical connection.
In the conventional method, the density of the conductive particles 1 that contribute to the conductivity in the thickness direction of the film 10 is low, and if the circuit becomes fine, connection cannot be obtained. In addition, the unevenness of the surface of the film 10 becomes large, and it becomes difficult to obtain contact with the electrode 12 on the circuit 11. The manufacturing method of the present invention improves the above-mentioned problems and enables electrical connection of fine circuits.

FIG. 3 (a) is a portion according to claim 1 of the present invention in the process of producing the anisotropically conductive resin film-shaped molded product of the present invention, in which the conductive particles 1 are attached to the adhesive material 2. It is the figure scattered on the layer of, and the conductive particles 1 are fixed by the adhesive force of the adhesive material 2. FIG. 3B is a portion according to claim 2 of the present invention in the process of producing the anisotropic conductive resin film-shaped molded product of the present invention, in which the conductive particles 1 are placed on the adhesive layer. FIG. 6 is a diagram in which the mask 4 is in contact with and fixed to the adhesive material 2 inside a through hole 5. The conductive particles 1 can be rolled on the mask 4 with a brush or the like and put into the through holes 5 of the mask 4. Therefore, an anisotropic conductive resin film-shaped molded product in which the conductive particles are present in a desired arrangement on the film surface can be obtained.

3 (c) and 3 (d) are portions according to claim 3 of the present invention, in which a layer of conductive particles is formed on the surface of the adhesive material to a thickness not less than the particle diameter of the conductive particles. It shows the step of pressing the conductive particle layer against the pressure-sensitive adhesive material surface after it is provided. FIG. 3C is a diagram when a conductive particle layer is provided on the surface of the adhesive material 2 to a thickness equal to or larger than the particle diameter of the conductive particles 1, and FIG. The process of pressing the material surface with the rubber roll 6 is shown. By this step, the contact area between the conductive particles and the pressure-sensitive adhesive layer is increased to make the fixing of the conductive particles uniform and reliable, and the conductive particles are sandwiched between the conductive particles and are not in contact with the pressure-sensitive adhesive layer. By pressing the conductive particles and forcibly bringing them into contact with the pressure-sensitive adhesive layer, the density of the conductive particles in the anisotropic conductive resin film-shaped molded article can be increased. Moreover, since it is possible to reduce the conductive particles that are not in contact with the adhesive layer, it becomes easy to remove the surplus conductive particles that do not contribute to the conductivity.

FIG. 3 (e) is a portion according to claim 4 of the present invention, in which after the layer of the conductive particles 1 is provided on the surface of the adhesive material 2, the conductive particle layer is pressed against the surface of the adhesive material. And conductive particles 1
3 shows a step of embedding the conductive particle layer in the pressure-sensitive adhesive layer to a depth of ½ or less of the particle diameter of. By embedding the conductive particle layer in the adhesive material layer, it is possible to form a structure in which the conductive particles are projected from the film surface on the surface of the anisotropic conductive resin film-shaped molded product that was in contact with the adhesive material. The electrode 12 and the conductive particle 1 in FIG.
The electrical connection with can be secured. Further, since the embedding amount of the conductive particles can be freely set by changing the pressing pressure, the protrusion amount of the conductive particles can be easily set optimally.

FIGS. 3 (f) and 3 (g) are portions according to claim 5 of the present invention, in which conductive particles are held on a charged body by an electrostatic force and the charged body is pressed against the surface of the adhesive material. Then, the step of transferring the conductive particles to the surface of the adhesive material is shown. FIG. 3 (f) is a diagram when the conductive particles 1 are held on the charging body 7 by electrostatic force, and FIG. 3 (g) presses the charging body 7 against the surface of the adhesive material 2 to make the conductive material 7 conductive. It shows a process of transferring the particles 1 to the surface of the adhesive material 2. When a charged body charged with a different charge from that of the conductive particles is brought close to the conductive particles, the conductive particles are held on the charged body by electrostatic force. At this time, since the conductive particles on the charged body are charged to the same electric charge, the conductive particles repel each other and are arranged on the charged body in a single layer state without aggregation. Therefore, by transferring the conductive particles on the charged body to the surface of the adhesive material, an array of conductive particles in a single layer state without aggregation can be formed on the adhesive surface, and the conductive particles are formed on the film surface. An anisotropically conductive resin film-shaped molded product uniformly dispersed is obtained.

FIGS. 3 (h) and 3 (i) show a portion according to claim 6 of the present invention, in which a mask is provided on the charged body, and conductive particles are provided on the charged body in the through hole portion of the mask. The figure shows a process of holding by electrostatic force, pressing the charged body against the surface of the adhesive material, and transferring the conductive particles to the surface of the adhesive material. Figure 3
FIG. 3H is a diagram when the mask 4 is provided on the charged body 7 and the conductive particles are held on the charged body in the through-hole portion of the mask 4 by electrostatic force. FIG. 7 shows a step of pressing 7 onto the surface of the adhesive material 2 to transfer the conductive particles 1 to the surface of the adhesive material. The mask may be removed before the step of pressing the charged body against the adhesive material surface.
As shown in (i), the surface of the adhesive may be pressed with the mask attached.

When a charged body charged with a charge different from that of the conductive particles is brought close to the conductive particles, the conductive particles are held on the charged body by electrostatic force. At this time, the conductive particles on the mask are attracted by the electrostatic force on the charged body in the through-hole portion of the mask exposed on the surface to form an array in which the conductive particles are adsorbed in the through-hole portion of the mask. By reducing the charge amount of the mask, it is possible to reduce the amount of particles attached to the mask. Further, by increasing the difference in the amount of charge between the mask and the charged body, it is possible to provide a difference in the attraction force of the conductive particles and remove only the conductive particles adsorbed on the mask by blowing air. Therefore, by transferring the conductive particles on the charged body to the surface of the adhesive material,
An anisotropic conductive resin film-shaped molded product in which conductive particles are present in a desired arrangement on the film surface can be obtained.

FIG. 4A is a portion according to claim 7 of the present invention, in which the conductive particles 1 and the adhesive material 2 are charged with different charges, and the conductive particles are attached to the surface of the adhesive material 2 by an electrostatic force. 1
3 shows a step of spraying to provide a conductive particle layer. In this step, the same effect can be achieved by using the charged body 7 of FIG. 3 (f) as a charged adhesive layer, and the conductive particles are uniformly dispersed on the film surface without the step of transferring the conductive particles. A directional conductive resin film-shaped molded product is obtained. Further, as shown in FIG. 4 (b), the same effect can be achieved by using the charged body 7 shown in FIG. 3 (h) as a charged adhesive layer, and the conductive particles can be transferred without the step of transferring the conductive particles. An anisotropically conductive resin film-shaped molded product in which the conductive particles are uniformly dispersed on the film surface is obtained.

When the pressure-sensitive adhesive layer charged to a different charge from the conductive particles is brought close to the conductive particles, the conductive particles are held on the pressure-sensitive adhesive by electrostatic force. At this time, the conductive particles on the mask are attracted by the electrostatic force on the adhesive material of the through holes on the mask exposed on the surface, and an array in which the conductive particles adhere only on the through holes of the mask is formed. It is possible to reduce the amount of particles adhering to the mask by reducing the charge amount of the mask, and since the mask and conductive particles are not adhered, it can be easily removed by blowing air or using a brush. . Therefore, an anisotropic conductive resin film-shaped molded product in which conductive particles are present in a desired arrangement on the film surface can be obtained.

FIG. 4 (c) is a portion according to claim 8 of the present invention, in which fibrous conductors are used in place of the conductive particles,
The fibrous conductor 8 and the adhesive material 2 are charged with different charges,
It shows a process of spreading the fibrous conductor 8 on the surface of the adhesive material 2 by an electrostatic force and providing a conductive particle layer. The fibrous conductor stands upright with its major axis perpendicular to the surface of the charged body due to repulsion by the electrostatic force between the fibrous conductors when sprayed on the charged body by electrostatic force. By pressing the charged body on which the fibrous conductors are dispersed onto the surface of the adhesive material, or by using the charged body as the surface of the adhesive material 2 as shown in FIG. Can be fixed in an upright position. Therefore, according to this method, an anisotropically conductive resin film-like molded product in which the fibrous conductor is upright in the film thickness direction can be obtained. At this time, by reducing the diameter of the fibrous conductor, it is possible to increase the array density in the plane of the conductor, and increase the length of the long axis of the fibrous conductor to increase the film thickness. However, the film strength can be improved.

4 (d), (e) and (f) are parts according to claim 9 of the present invention, in which the conductive particles or fibrous conductors can be removed by heating or pressurization. It shows the steps for forming conductive particles, fibrous conductors, or aggregates thereof whose surface is previously coated with an insulating layer. FIG. 4D is a diagram in which the conductive particles 1 on which the electric insulating layer (insulating layer) 9 is formed are scattered on the surface of the adhesive material 2.
(E) is a diagram when the obtained sample is inserted between the circuits 11. FIG. 4F is a diagram showing a state in which the insulating layer 9 is caused to flow by heating and pressurization, and the circuits 11 are electrically connected. Since the insulating layer does not dissolve in the film-forming resin solution, it exists in the film-forming resin solution while holding the insulating layer, and since the particles are fixed by the adhesive material, the particles agglomerate in the film-forming resin solution. Without doing so, the film is uniformly dispersed in the plane of the film.
Therefore, even if the conductive particles are densely packed in contact with each other,
Insulation in the plane direction is maintained by the insulating layer between the particles. Electrical connection between the electrodes facing each other is performed under pressure or under heat and pressure, and the insulating layer on the particle surface is fluidized and removed.

4 (g) and 4 (h) are portions according to claim 10 of the present invention, in which conductive particles or fibrous conductors are coated with an electrically insulating layer in advance. A conductor or an aggregate thereof, by removing the front surface and the back surface of the resin film-shaped molded article to make the thickness equal to or smaller than the particle diameter of the conductive particles or the fiber length of the fibrous conductor, and the resin film shape. It shows the process when the insulating layer of the conductive particles or the fibrous conductor exposed on the front surface and the back surface of the molded product is removed. FIG. 4G shows the insulating layer 9
FIG. 4 (h) shows a film-shaped molded product obtained by using the conductive particles 1 whose surface is covered with 1. The insulating layer 9 exposed on the film surface is removed. Since the insulating layer does not dissolve in the film-forming resin solution, it exists in the film-forming resin solution while holding the insulating layer, and since the particles are fixed by the adhesive material, the particles agglomerate in the film-forming resin solution. Without doing so, the film is uniformly dispersed in the plane of the film.

Therefore, even if the conductive particles are densely packed so that they are in contact with each other, the insulating coating layer between the particles maintains the in-plane insulating property. Since a resin that is incompatible with the film-forming resin is selected for the insulating layer, it is possible to dissolve and remove only the insulating layer exposed on the film surface by selecting an appropriate solvent. It is also possible to simultaneously remove the film-forming resin and the insulating layer on the surface of the conductive particles by a physical method such as a solvent having high solubility or plasma treatment. According to this method, even if it is difficult to remove the insulating layer at the time of electrical connection, an anisotropic conductive resin film-like molded article having a high conductive point density is obtained by using the conductive particles coated with the insulating layer. Can be used.

FIG. 4 (i) is a portion according to claim 11 of the present invention, which is an anisotropic conductive resin film-like molded article using a film-forming resin 13 having adhesiveness by heating and pressurizing or light irradiation. The cross-sectional structure is shown. Achieving adhesion and electrical connection between electrodes at the same time by using a thermoplastic resin that is melted and cured by heat and pressure or light irradiation for the film forming resin, uncured thermosetting resin, photocurable resin, etc. Is possible. Specifically, the conductive particles are sandwiched between the electrodes in a state where the anisotropically conductive resin film-shaped molded product of the present invention is inserted between the electrodes and sandwiched by pressure, and electrical connection is obtained. The conductive particles are deformed by the pressurization at this time, or the conductive particles are embedded in the electrode so that the electrode and the film-forming resin are in contact with each other. While applying pressure, the film-forming resin is cured by heating or light irradiation, and the state where the electrodes are bonded is maintained. The step of electrically connecting by pressure and the step of adhering the electrodes by heating or light irradiation may be performed at the same time, and a step of performing an electrical function inspection or the like of the electronic component connected between these steps can be provided.

[0044]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited thereto. First, the materials and conditions used in this example and comparative example are shown below. The adhesive material is a 10 μm thick polyisobutylene adhesive material (Vistanex,
Tonex Co., Ltd.) or a 10 μm thick silicone adhesive (light release type, Toshiba Silicone Co., Ltd.) with a thickness of 50
It is used by coating on a PET base film having a thickness of μm. The conductive particles are nickel (Ni) particles having an average particle diameter of 40 μm and produced by a gas atomizing method, a nickel fibrous conductor having an average fiber length of 40 μm and a fiber diameter of about 20 μm, or an average particle diameter of 4
Plastic conductive particles in which a 0.2 μm gold layer was provided on the surface of 0 μm polystyrene spherical particles were used.

Insulating coating conductive particles having an insulating layer on the surface of Ni particles, CM4000 (methanol-soluble nylon, Toray Co., Ltd.) was used as an insulating coating material, and Coatmizer (Freund Industrial Co., Ltd.) was used with methanol as a solvent. )), A wet insulating layer having a thickness of about 0.5 μm was applied. The film-forming resin is a polyimide resin obtained by applying a DMF solution of polyamic acid, followed by drying and imidization, or Epicoat 1001 / Epicoat 828 / Nipol 1032
(Nitrile rubber, Nippon Zeon Co., Ltd.) / Hitanol 240
0 (alkylphenol, Hitachi Chemical Co., Ltd.) / Curezol 2PZ (2-phenylimidazole, Shikoku Chemical Co., Ltd.) = 50/20/20/10/2 Any of the thermosetting epoxy resins obtained by drying was used.

The manufacturing process is specifically shown in each example, but an applicator type coating machine was used for coating the adhesive material and the film-forming resin. The polyamic acid drying condition is 130 ° C. for 10 minutes, the dehydration imidization condition is 400 ° C. for 10 minutes, and the decomposition and removal of the polyimide for exposing the surface of the conductive particles on the polyamic acid application surface is performed by dipping in a sodium hydroxide aqueous solution. Went by. Further, the drying condition after coating the thermosetting epoxy resin is 80 ° C. for 10 minutes, and the method of exposing the conductive particle surface on the film forming resin coating surface side is to wipe with a non-woven fabric impregnated with toluene and remove by dissolving. went. The obtained anisotropic conductive resin film-shaped molded product was evaluated by a line width of 50 μm, a pitch of 100 μm, and a thickness of 35 μm.
An anisotropic conductive resin obtained by using a flexible circuit board (FPC) having a total circuit width of 50 mm having a copper circuit of m, and positioning the circuits of the circuit boards facing each other. The film-shaped molded product was inserted, and the connection resistance and the insulation resistance were measured in a state where the circuit was pressure-contacted with a pressure of 10 kg / cm ² .

However, in Example 9 in which the insulating coated conductive particles removed by heating and pressing were used, the sample was inserted between the circuits and kept under pressure and heating (10 kg / cm ² , 150 ° C.) for 30 seconds. After removing the insulating coating layer, measurement was performed by cooling to room temperature while applying pressure. Further, in Example 11 for the purpose of obtaining a mechanical connection by adhesion between circuits at the same time as electrical connection, the sample was inserted between the circuits for evaluation, and a pressure state (10 kg / cm ² ) was applied.
And when heated at pressure (10 kg / cm ² , 170
(° C) for 30 seconds, the circuits were adhered to each other by the sample, and the temperature was measured twice when cooled to room temperature under normal pressure. The measurement conditions are
The connection resistance between a pair of FPCs is measured with a measurement current of 1 mA,
The insulation resistance between adjacent connection circuits was measured at a measurement voltage of 100V. The results are shown in Table 1 for all the examples and comparative examples.

Example 1 Ni particles were sprayed on the polyisobutylene-coated surface of a PET film using a dry particle spraying device for spraying powder through a sieve having openings of 50 μm. A polyamic acid solution was applied to the particle-dispersed surface, dried, and then peeled from the interface with polyisobutylene and imidized by heat treatment. This film had a thickness of about 25 μm in the polyimide portion, but since the thin film of polyimide covered the particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially cover the polyimide on the surface layer. It was decomposed and removed to expose the particle surface. The electrical characteristics of the obtained sample were evaluated by inserting it between evaluation circuits and applying pressure (10 kg / cm ² ).

Example 2 A dry particle-dispersing apparatus was used in which a mask (a non-charged nylon mesh having openings of 50 μm) was brought into close contact with the polyisobutylene-coated surface of a PET film, and the powder was sprayed through a sieve having openings of 50 μm. The Ni particles were used to spray the mask surface. After spraying, the particles on the mask were tumbled using a static elimination brush so that many particles would enter the through holes of the mask. Next, after removing particles not held by the adhesive material by blowing compressed air, the mask was peeled off from the surface of the adhesive material. A polyamic acid solution is applied to the particle-dispersed surface, peeled off from the interface with polyisobutylene after drying,
It was imidized by heat treatment. This film had a thickness of about 25 μm in the polyimide portion, but since the thin film of polyimide covered the particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially cover the polyimide on the surface layer. It was decomposed and removed to expose the particle surface. The electrical characteristics of the obtained sample were evaluated by inserting it between evaluation circuits and applying pressure (10 kg / cm ² ).

Example 3 Ni particles were dispersed on the polyisobutylene-coated surface of the PET film by using a dry type particle-dispersing apparatus which sprays the powder through a sieve having openings of 50 μm. At this time, the scattered N
The i-particles were aggregated to each other in a number of 3 to 10 and locally formed layered portions in various places. Covered with a PET film for 25μm cover into the particles scatter plane, is inserted between rubber roll was pressed under a pressure of 1 kg / cm ^2. Then, the PET film for a cover was peeled off, and the dispersion state of Ni particles was observed. The Ni particles were pressed by the surface of the adhesive material to form almost one layer. A DMF solution of polyamic acid was applied to the Ni particle-dispersed surface, dried, and then peeled off from the interface with polyisobutylene, followed by heat treatment for imidization. This film had a thickness of about 25 μm in the polyimide portion, but since the polyimide particle thin film covered the Ni particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially remove the polyimide on the surface layer. Disassembled and removed into
The particle surface was exposed. The electrical characteristics of the obtained sample were evaluated by inserting it between the evaluation circuits and applying pressure (10 kg / cm ² ).
I went there.

Example 4 Ni particles were sprayed on the polyisobutylene-coated surface of a PET film by using a dry particle spraying device which sprays powder through a sieve having openings of 50 μm. Inserted between a rubber roll is covered with a PET film for 25μm cover over the Ni particles spread side, pressed with a pressure of 5 kg / cm ^2. After this,
The PET film for a cover was peeled off, and the dispersion state of Ni particles was observed. Almost one layer of Ni particles was embedded in the adhesive material on the average of about 5 μm. A DMF solution of polyamic acid was applied to the particle-dispersed surface, dried, and then peeled from the polyisobutylene surface, followed by heat treatment for imidization. This film had a thickness of about 25 μm in the polyimide portion, but since the thin film of polyimide covered the particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially cover the polyimide on the surface layer. It was decomposed and removed to expose the particle surface. The electrical characteristics of the obtained sample were evaluated by inserting it between evaluation circuits and applying pressure (10 kg / cm ² ).

Example 5 Ni particles were sprayed on an aluminum foil using a dry particle spraying device for spraying powder through a sieve having openings of 50 μm. An acrylic plate charged to +3 kV using a corona charging device was placed above the Ni particle-dispersed surface so as to face the Ni particle-dispersed surface at a distance of about 1 cm. At this time, Ni particles on the aluminum foil were adsorbed on the acrylic plate surface by electrostatic force. Further, since the Ni particles adsorbed on the acrylic plate surface are charged to the same potential, repulsive force due to static electricity is generated between the conductive particles, and there is no agglomeration between particles,
One particle layer was formed. The particle surface was pressed against the pressure sensitive adhesive surface of polyisobutylene to transfer the Ni particles onto the pressure sensitive adhesive surface. A solution of polyamic acid was applied to the particle transfer surface, dried, and then peeled off from the polyisobutylene surface, followed by heat treatment for imidization. This film is about 2 in the polyimide part
Although it had a thickness of 5 μm, the surface of the polyamic acid solution coated surface was covered with a thin film of polyimide, so it was immersed in an aqueous sodium hydroxide solution to partially decompose and remove the surface polyimide, Exposed. The electrical characteristics of the obtained sample were evaluated by inserting it between evaluation circuits and applying pressure (10 kg / cm ² ).

Example 6 Ni particles were sprayed on an aluminum foil using a dry particle spraying device for spraying powder through a sieve having openings of 50 μm. Next, the mask surface side of the plate in which the acrylic plate and the mask (stainless steel mesh having a mesh size of 50 μm) are laminated is charged to +3 kV using a corona charging device, and the mask surface is about 1 cm above the Ni particle dispersion surface. At a distance of Ni
It was installed so as to face the particle-dispersed surface. At this time, the Ni particles on the aluminum foil were adsorbed to the through holes of the mask by electrostatic force. Further, since the Ni particles adsorbed on the mask surface are charged to the same potential, a repulsive force due to static electricity is generated between the Ni particles, and there is no agglomeration between particles to form one particle layer. The particle surface was pressed against the pressure sensitive adhesive surface of polyisobutylene to transfer the Ni particles onto the pressure sensitive adhesive surface. A DMF solution of polyamic acid was applied to the particle transfer surface, dried, and then peeled from the polyisobutylene surface and imidized by heat treatment. This film had a thickness of about 25 μm at the polyimide portion, but since the polyimide thin film covered the particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially remove the polyimide on the surface layer. It was decomposed and removed to expose the particle surface. The electrical characteristics of the obtained sample were evaluated by inserting it between evaluation circuits and applying a pressure (10 k
g / cm ² ).

Example 7 Ni particles were sprayed on an aluminum foil using a dry particle spraying device which sprays a powder through a sieve having openings of 50 μm. Next, a mask (made of nylon, opening 50 μm) closely attached to the polyisobutylene coated surface on the PET film.
The mask surface side of was charged to +3 kV using a corona charging device, and was placed above the Ni particle-dispersed surface such that the mask surface was spaced about 1 cm away from the Ni particle-dispersed surface.
At this time, the Ni particles on the aluminum foil entered into the holes of the mask by electrostatic force and were adhesively fixed to the adhesive material. Further, since the Ni particles fixed to the surface of the adhesive material are charged to the same potential, a repulsive force due to static electricity is generated between the Ni particles, and there is no agglomeration between particles to form one particle layer. Next, the mask was peeled off from the adhesive material surface. A polyamic acid solution was applied to the particle-dispersed surface, dried, peeled off from the polyisobutylene surface, and heat-treated to be imidized. This film had a thickness of about 25 μm in the polyimide portion, but since the thin film of polyimide covered the particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially cover the polyimide on the surface layer. It was decomposed and removed to expose the particle surface. The electrical characteristics of the obtained sample were evaluated by inserting it between the evaluation circuits and applying pressure (10 kg / cm ² ).

Example 8 A fibrous conductor was sprayed on an aluminum foil by using a dry particle spraying device which sprays powder through a sieve having openings of 50 μm. Next, using a corona charging device, the mask surface side of a mask (nylon mesh with openings of 50 μm) closely attached to the polyisobutylene coated surface on the PET film was used +
It was charged to 3 kV, and was placed above the fibrous conductor so that the mask surface faced the fibrous conductor-dispersed surface at a distance of about 1 cm. At this time, the fibrous conductor on the aluminum foil entered into the hole of the mask by electrostatic force and was adhesively fixed to the adhesive material. At this time, the fibrous conductor was substantially upright on the surface of the adhesive material and fixed in a state of being embedded in the adhesive material by several μm. Further, since the fibrous conductors fixed to the adhesive surface are charged to the same potential, a repulsive force due to static electricity is generated between the fibrous conductors, and there is no aggregation between the fibrous conductors to form one particle layer. Was. Next, the mask was peeled off from the adhesive material surface. A polyamic acid solution was applied to the particle-dispersed surface, dried, peeled off from the polyisobutylene surface, and heat-treated to be imidized. This film is about 25μm in polyimide part
There was a thickness of, but since the thin film of polyimide was covering the surface of the particles on the polyamic acid solution coated surface, it was immersed in an aqueous solution of sodium hydroxide to partially decompose and remove the polyimide on the surface layer to expose the surface of the particles. Let The electrical characteristics of the obtained sample were evaluated by inserting the sample between evaluation circuits and applying a pressure (10
KG / cm ² ).

Example 9 Insulating conductive particles were sprayed onto the polyisobutylene-coated surface of a PET film using a dry particle spraying device in which powder was sprayed through a sieve having openings of 50 μm. A polyamic acid solution was applied to the particle-dispersed surface, dried, peeled off from the polyisobutylene surface, and heat-treated to be imidized. This film had a thickness of about 25 μm in the polyimide portion, but since the thin film of polyimide covered the particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially cover the polyimide on the surface layer. It was decomposed and removed to expose the particle surface. The electrical characteristics of the obtained sample were evaluated by inserting it between the evaluation circuits and heating under pressure (10 kg / cm ² , 1
It was held at 50 ° C. for 30 seconds and then cooled to room temperature while applying pressure. After the evaluation, the circuit surface was observed, but the adhesion of the insulating coating layer was not recognized.

Example 10 Insulating conductive particles were sprayed onto the polyisobutylene-coated surface of a PET film using a dry particle spraying device in which powder was sprayed through a sieve having openings of 50 μm. A polyamic acid solution was applied to the particle-dispersed surface, dried, peeled off from the polyisobutylene surface, and heat-treated to be imidized. This film had a thickness of about 25 μm in the polyimide portion, but since the thin film of polyimide covered the particle surface on the polyamic acid solution coated surface side, it was immersed in an aqueous sodium hydroxide solution to partially cover the polyimide on the surface layer. It was decomposed and removed to expose the particle surface. Next, this sample was immersed in methanol to dissolve and remove the insulating coating layer on the particles exposed on the surface. The electrical characteristics of the obtained sample were evaluated by inserting it between the evaluation circuits and applying pressure (10 kg / cm ² ).

Example 11 Plastic conductive particles were sprayed onto a silicone adhesive-coated surface of a PET film by using a dry particle spraying device which sprays powder through a sieve having openings of 50 μm. A thermosetting epoxy resin was applied to the particle-dispersed surface and dried. This film had a thickness of about 25 μm in the film-forming resin portion without plastic conductive particles, but the film-forming resin coating surface side had a thin film of the film-forming resin covering the particle surface, so a non-woven fabric impregnated with toluene was used. I wiped it off several times. At this time, since the plastic conductive particles had a structure protruding from the film surface, the thin film of the film-forming resin on the particles was easily removed. Next, the film-forming resin was peeled from the pressure-sensitive adhesive surface to obtain a sample for evaluation. The electrical characteristics are evaluated by inserting them between the circuits for evaluation under pressure (10 kg / cm ² ) and by heating for 30 seconds under pressure (10 kg / cm ² , 170 ° C). After the sample was bonded, the test was performed twice when it was cooled to room temperature under normal pressure. After the bonding, the conductive particles were compressed and deformed to a thickness of about 15 μm, the film-forming resin was filled between the circuits, and the resin was cured by crosslinking, and the circuits were firmly bonded.

Comparative Example As shown in FIG. 5A, the conductive particles 1 of Ni were dispersed in a DMF solution 14 of polyamic acid in an amount of 30% by volume, and a PET substrate was prepared using an applicator coating device. Cast on Film 3. As shown in FIG. 5B, the conductive particles 1 settled immediately after casting. After drying this, P
It was peeled from the surface of the ET film 3 and imidized by heat treatment. As shown in FIG. 5C, the film 10 had a large amount of aggregates of the conductive particles 1 and had large surface irregularities, but the average film thickness was about 70 μm.
Since the particle surfaces were not exposed on both sides of this film 10, the polyimide surface was partially decomposed and removed by immersing this film in an aqueous sodium hydroxide solution, and the thickness of the polyimide portion was reduced to the particle diameter of the conductive particles or less. And the grain surface was exposed.

At this time, the conductive particles 1 in the film 10 were mostly unevenly distributed on the side of the PET film 3 due to the sedimentation of the conductive particles. Therefore, as shown in (d) and (e) of FIG. PE coated with polyisobutylene adhesive 15
The T film 16 was laminated and immersed in an aqueous sodium hydroxide solution, and the amount of polyimide decomposition on each surface was adjusted by the immersion time. We also tried to reduce the coating thickness to reduce the amount of polyimide to be removed, but during coating, particles agglomerated between the applicator and PET film, causing numerous streaks and forming a film. There wasn't. The evaluation of the electrical characteristics of the obtained sample shown in FIG. 5 (f) was carried out under pressure (10 kg / cm ² ) by inserting it between the evaluation circuits as shown in FIG. 2 (b).

[0061]

[Table 1] Note) A: Occurrence rate (%) of defective connection resistance (10Ω or more) B: Incidence rate (%) of defective insulation resistance (10 ⁶ Ω or less) In Example 11a, when pressure was applied, and 11b was after pressure and heating. Show.

[0062]

EFFECTS OF THE INVENTION According to the present invention, the filling amount of the conductive particles in the anisotropic conductive resin film-shaped molded article can be increased,
It is possible to increase the number of conductive points per unit area of the molded product,
An anisotropic conductive resin film-like molded product having better decomposition performance than that of the conventional one can be obtained, and high-definition electrical connection between electrodes becomes possible.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating the order of production in a method for producing an anisotropically conductive resin film-shaped molded product according to the present invention.

FIG. 2 is a cross-sectional view when a circuit is connected by an anisotropic conductive resin film-shaped molded product, (a) is a case where the molded product obtained by the present invention is used, and (b) is a conventional manufacturing method. This is the case of using the molded product obtained in.

FIG. 3 is a cross-sectional view illustrating various production examples in the method for producing an anisotropically conductive resin film-shaped molded product of the present invention.

FIG. 4 is a cross-sectional view illustrating various production examples in the method for producing an anisotropically conductive resin film-shaped molded product of the present invention.

FIG. 5 is a cross-sectional view illustrating the order of manufacturing a conventional anisotropically conductive resin film-shaped molded product.

[Explanation of symbols]

1 ... Conductive particles, 2 ... Adhesive material, 3 ... Base film, 4 ...
Mask, 5 ... Through hole, 6 ... Rubber roll, 7 ... Charged body, 8 ...
Fibrous conductor, 9 ... Electrical insulating layer, 10 ... Film forming resin, 11 ... Circuit, 12 ... Electrode, 13 ... Film forming resin, 14 ... Film forming resin solution, 15 ... Polyisobutylene adhesive, 16 ... PET film

Claims (11)

[Claims] 1. An anisotropic conductive material in which conductive particles are uniformly dispersed in the plane direction of a film-shaped molded article, and which has conductivity only in the thickness direction of the film-shaped molded article through the conductive particles exposed on the front and back sides. In the method for producing a resin film-shaped molded article, conductive particles are adhesively fixed to the adhesive material surface, a film-forming resin that is incompatible with the adhesive material is filled between the conductive particles, and the film-forming resin is dried or A method for producing an anisotropically conductive resin film-shaped molded article, which comprises peeling an adhesive material from a film-forming resin after curing. 2. An anisotropic conductive resin film according to claim 1, wherein a film or net having through holes is provided on the adhesive material surface, and the conductive particles are adhesively fixed to the adhesive material surface in the through holes of the film or net. Manufacturing method of molded article. 3. The anisotropic conductive material according to claim 1, wherein the conductive particle layer is provided on the surface of the adhesive material to a thickness equal to or larger than the particle diameter of the conductive particles, and then the conductive particle layer is pressed against the surface of the adhesive material. Of producing a resinous resin film molding. 4. After providing a conductive particle layer on the surface of the adhesive material,
The anisotropic conductive resin according to claim 1, 2 or 3, wherein the conductive particle layer is pressed against the pressure-sensitive adhesive material surface, and the conductive particle layer is embedded in the pressure-sensitive adhesive material layer to a depth of 1/2 or less of the particle diameter of the conductive particles. A method for producing a film-shaped molded product. 5. The method according to claim 1, 3 or 4, wherein the conductive particles are held on the charged body by an electrostatic force and the charged body is pressed against the adhesive material surface to transfer the conductive particles to the adhesive material surface. Method for producing a conductive resin film-shaped molded product. 6. An anisotropic conductive resin according to claim 5, wherein a film or net having through holes is provided on the charged body, and the conductive particles are held on the charged body in the through holes of the film or net by electrostatic force. A method for producing a film-shaped molded product. 7. The electrically conductive particles and the adhesive material are charged to different electric charges, and the electrically conductive particles are dispersed on the surface of the adhesive material by electrostatic force to provide the electrically conductive particle layer, according to any one of claims 1 to 4. Method for producing a conductive resin film-shaped molded product. 8. The method for producing an anisotropically conductive resin film-shaped molded article according to claim 5, 6 or 7, wherein a fibrous conductor is used instead of the conductive particles. 9. The anisotropic conductive resin film according to claim 1, wherein the surface of the conductive particles or the fibrous conductor is previously coated with an electrically insulating layer which can be removed by heating or pressing. Molded product manufacturing method. 10. A conductive particle or a fibrous conductor whose surface is previously coated with an electrically insulating layer, wherein a part of the front surface and the back surface of the resin film-shaped molded product is removed to obtain the thickness of the conductive particle. 9. The anisotropic conductive resin according to any one of claims 1 to 8, wherein the particle size is less than or equal to the particle size of the resin or the fiber length of the fibrous conductor, and the electrically insulating layer exposed on the front surface and the back surface of the resin film-shaped molded product is removed. A method for producing a film-shaped molded product. 11. The method for producing an anisotropically conductive resin film-shaped molded article according to claim 1, wherein a film-forming resin having an adhesive property by heating and pressing or light irradiation is used.