JP2011109028A - Conductive adhesive film - Google Patents

Abstract

Provided is a conductive adhesive film capable of lowering the heating temperature at the time of connecting wiring boards and reducing the manufacturing cost of the wiring boards by employing a wiring board having low heat resistance.
Electrodes 11a, 11b, 12a and 12b provided on the wiring boards are made conductive by being sandwiched and deformed while being heated between the wiring boards 8 and 10, and the wiring boards are bonded together. It is the conductive adhesive film 1 which comprises a wiring board connection body, Comprising: One or more thermosetting resin layers 2, One or more hardening agent layers 3 which react and harden | cure with the said thermosetting resin, The said heat | fever A separation layer 4 that separates the curable resin layer and the curing agent layer, and the separation layer is destroyed in the sandwiching deformation process so that the thermosetting resin and the curing agent react with each other. In addition, the conductive particles are blended in at least one of the above layers.
[Selection] Figure 1

Description

  The present invention relates to a conductive adhesive film. Specifically, by being sandwiched and deformed while being heated between opposing wiring boards, the electrodes provided on these wiring boards are made conductive, and the above-mentioned wiring boards are bonded to form a conductive board connection body. Agent film.

  In electronic devices, a structure in which a plurality of wiring boards are connected by electrically connecting electrodes provided on two wiring boards is often employed. For example, flexible wiring boards are frequently used for applications such as wiring to movable parts of electronic devices. With the downsizing and higher functionality of electronic devices, wiring board connectors between the flexible wiring boards and the flexible wiring boards are used. Various wiring board connectors such as a wiring board connector of a wiring board and a rigid wiring board are used.

  A conductive adhesive is often used to connect the wiring boards. The conductive adhesive is configured by dispersing fine conductive particles in an insulating resin adhesive. By interposing the conductive adhesive in a region including the opposing electrode of the wiring board to be connected and applying pressure and temperature to sandwich the wiring board, the conductive particles are adhered between the electrodes at the same time. These electrodes are stretched to be conducted, and the adjacent electrodes are electrically insulated from each other. As the conductive adhesive, a conductive adhesive film (ACF: Anisotropic Conductive Film) is often employed.

  The conductive adhesive film includes a thermosetting resin such as an epoxy resin, conductive particles, and a curing agent. The said hardening | curing agent is mix | blended in the said thermosetting resin layer in the state enclosed with the microcapsule. By applying pressure and temperature to the conductive adhesive, the microcapsules are broken and the curing agent is diffused in the thermosetting resin, and the electrodes are electrically connected through the conductive particles. Then, the thermosetting resin is cured to form a wiring board connector.

Japanese Patent Laid-Open No. 4-96981

  The microcapsules contained in the conductive adhesive are configured to be broken mainly by heating, and are usually broken at 80 ° C. or higher. However, heating is performed through the wiring board, and heat of 180 ° C. or more acts on the wiring board in the connection process so that the microcapsules can be destroyed in a short time. For this reason, the wiring board is easily damaged by heating. On the other hand, if the heating temperature is set low, the microcapsules cannot be sufficiently destroyed, and the thermosetting resin and the curing agent cannot be sufficiently reacted. For this reason, poor curing of the thermosetting resin is likely to occur. When poor curing occurs, a “floating” or “return” phenomenon occurs in which the distance between the electrodes facing each other increases, leading to poor connection between the electrodes. On the other hand, it may be possible to increase the heating time in order to destroy the microcapsules, but the efficiency of the manufacturing process is reduced.

  In addition, by adopting a wiring board having low heat resistance such as polyethylene naphthalate (PEN), polyethylene terephthalate (PET) or acrylic resin for one or both of the wiring boards constituting the wiring board connector, the wiring board connector The manufacturing cost can be reduced. However, in the conventional connection method, as described above, since a high temperature acts on the wiring board, there is a problem that the wiring board is easily damaged or deformed by heat.

  The present invention provides a conductive adhesive film that can reduce the heating temperature when connecting the wiring boards and can reduce the manufacturing cost of the wiring board connector by adopting a wiring board having low heat resistance. The issue is to provide.

  In the invention described in claim 1 of the present application, the electrodes provided on the wiring boards are made conductive by being sandwiched and deformed while being heated between the wiring boards, and the wiring boards are bonded to each other. 1 or more thermosetting resin layers, one or more curing agent layers that react and cure with the thermosetting resin, the thermosetting resin layer, and the curing An isolation layer that isolates the agent layer, and the isolation layer is broken in the pinching deformation process so that the thermosetting resin and the curing agent react with each other. Conductive particles are blended in at least one layer.

  The conductive adhesive film according to the present invention has a configuration in which a thermosetting resin as an adhesive component and a curing agent for curing the thermosetting resin are laminated via an isolation layer. By providing the isolation layer, the thermosetting resin and the curing agent do not react during storage or transportation. Therefore, stability is high and storage stability is good. Further, it is not necessary to enclose the curing agent in the microcapsule or to mix the thermosetting resin and the curing agent before the connecting step. In addition, since the thermosetting resin and the curing agent can be stored and transported together, the handleability is good.

  On the other hand, the isolation layer is configured to be destroyed by being pinched and deformed while being heated between the wiring boards in the wiring board connecting step. The electrodes to be connected are brought close to a distance of 1 to 2 μm in the connection step. The said isolation layer which concerns on this invention is destroyed mainly when a conductive adhesive film is pinched and deformed between wiring boards.

  For this reason, compared with the case where a hardening | curing agent is sealed in the microcapsule mainly destroyed by a heat | fever, even when the heating temperature in a connection process is low, an isolation layer can be destroyed reliably. Thereby, it becomes possible to reduce the temperature which acts on a wiring board at a connection process, and it can prevent that a wiring board is damaged by a heat | fever. It is desirable that the conductive adhesive film according to the present invention is configured to perform the connecting step by applying a temperature of 100 ° C. or lower.

  The thickness of each of the layers according to the present invention and the overall thickness are not particularly limited. The thickness of the thermosetting resin layer and the curing agent layer is preferably set so that an optimal curing reaction occurs according to the resin and the curing agent to be employed. On the other hand, the thickness of the isolation layer is preferably set as small as possible so as to be easily broken, and is preferably set to 5 μm or less.

  Further, the number of the thermosetting resin layer and the curing agent layer is not limited, and each may have a multilayer structure of two or more layers. The larger the number of layers, the more easily the thermosetting resin and the curing agent are mixed and react when subjected to pinching deformation. For this reason, it is preferable to increase the number of layers within a manufacturable range.

  The kind of the said thermosetting resin which concerns on this invention is not specifically limited. For example, an epoxy resin can be employed. The type of the epoxy resin is not particularly limited. For example, bisphenol A type, F type, S type, AD type, or a copolymer type epoxy resin of bisphenol A type and bisphenol F type, or a naphthalene type epoxy resin. A novolac type epoxy resin, a biphenyl type epoxy resin, a dichloropentane type epoxy resin, or the like can be used.

  What is necessary is just to select the said hardening | curing agent according to a thermosetting resin, for example, amine systems, such as an imidazole type, a hydrazide type, a boron trifluoride-amine complex, an amine imide, a polyamine type | system | group, a tertiary amine, and an alkyl urea type | system | group. , Dicyandiamide, anhydride, phenol, and modified products thereof can be used. Moreover, these can be utilized as single or 2 or more types of mixtures. Furthermore, in addition to these curing agents, a curing accelerator can also be blended. Moreover, shape-retaining resins such as phenoxy resin, acrylic resin, polyvinyl butyral, and polyvinyl alcohol can be blended so that the curing agent can be held in a solid body such as a film.

  The kind and form of the conductive particles are not particularly limited. For example, existing ones such as metal particles such as gold and nickel, and resin particles coated on a metal plating layer can be used. The said electroconductive particle should just be mix | blended with the at least 1 layer of said each layer. Moreover, electroconductive particle can also be mix | blended with all the layers.

  The isolation layer is made of a resin material that can be isolated so that the thermosetting resin and the curing agent do not react and can be easily broken in the connection process. The isolation layer is preferably formed of a resin material that melts at a temperature that acts upon connection, as in the fifth aspect of the invention. For example, resins such as phenoxy resin, acrylic resin, polyvinyl butyral, and polyvinyl alcohol can be employed. In order to promote mixing and reaction between the curing agent layer and the thermosetting resin layer, it is preferable to form the isolation layer from a material having a softening point lower than those layers. For example, it is preferable to select a material whose viscosity at 100 ° C. is lower than that of the curing agent layer or the thermosetting resin layer.

  The material which comprises each said layer is selected so that the conductive adhesive film of the said structure can perform the connection process by applying the temperature of 100 degrees C or less.

  The conductive adhesive film according to the present invention can be manufactured using various techniques. For example, it can manufacture by laminating | stacking the film-form material which comprises each layer. In addition, at least one layer can be formed in a film shape, and the material constituting the other layer can be applied to the surface of the film-like material and laminated.

  The thermosetting resin and the curing agent according to the present invention are provided in a layered manner via a separating layer. For this reason, when the softening temperature of each layer is different or the clamping pressure in the connection process does not act uniformly, the components of each layer move in the thickness direction before the isolation layer is destroyed, and the thermosetting There are cases where the resin and the curing agent cannot be mixed uniformly.

  The inventions described in claims 2 to 4 have been devised in order to avoid the inconvenience.

  The invention described in claim 2 is such that the surface of the conductive adhesive film and / or the boundary surface of each of the above layers is formed in an uneven shape.

  The conductive adhesive film is sandwiched between two wiring boards in the thickness direction. For this reason, when unevenness is provided on the surface of the film, high stress acts on the convex portion, and the isolation layer is easily broken at this portion. In addition, by forming the boundary surface of each layer in a concavo-convex shape, it becomes possible to vary the compressive stress acting on the surface of the isolation layer according to the concavo-convex during clamping, and the entire separation layer is affected by the applied clamping pressure. Can be uniformly broken. Thus, the destruction of a part of the isolation layer is not delayed, and the material constituting each layer does not flow in the surface direction before the isolation layer is destroyed. Therefore, the thermosetting resin and the curing agent can be made to act uniformly.

  The method for providing the irregularities is not particularly limited. As a method of providing unevenness on the surface of the conductive film, for example, the surface layer can be formed by a printing method with a required uneven pattern. Further, as a method of providing unevenness in the boundary layer, it is possible to transfer and form an uneven pattern with a press or the like in the middle of the lamination of each layer, and then laminate other layers.

  According to a third aspect of the present invention, the isolation layer is provided with irregularities. By providing irregularities in the isolation layer, it is possible to cause destruction in the entire area of the isolation layer when sandwiched, and to allow the curing agent to act uniformly on the thermosetting resin layer. In particular, by providing irregularities so that the thicknesses of the isolation layers are different, it is possible to promote breakage during pinching.

  The method for providing irregularities in the isolation layer is not particularly limited, and transfer processing using a press or the like, sandblast processing, etching processing, or the like can be employed.

  According to a fourth aspect of the present invention, the isolation layer is formed from a resin material that melts at a temperature that acts upon connection.

  By constituting the isolation layer so that it can be broken by heat in addition to the clamping pressure acting at the time of connection, the curing agent can be reliably applied to the thermosetting resin and cured. The present invention is intended to perform the bonding process at a temperature lower than that of the prior art, and is preferably configured so as to cause the above-described destruction at a temperature of 100 ° C. or lower to cause a curing reaction. As the resin material constituting the isolation layer, phenoxy resin, polyvinyl alcohol resin, acrylic resin, or the like can be used.

  According to a fifth aspect of the present invention, a plurality of the thermosetting resin layers are provided on the conductive adhesive film, and each layer is made of a different thermosetting resin material.

  For example, a highly heat resistant wiring board made of polyamide resin or the like and a low heat resistant wiring board such as acrylic resin may be joined. When the materials constituting such a wiring board are different, or when wiring boards having different electrode materials are joined, the wettability of the surface is different, so that one type of thermosetting resin may not ensure the adhesive strength. .

  The invention described in claim 5 corresponds to such a case, and according to the characteristics of the wiring board, the conductive adhesive film is configured to include a plurality of the thermosetting resin layers. It is. The kind of the plurality of thermosetting resins can be appropriately selected according to the kind of the wiring board or the surface coating agent.

  According to the sixth aspect of the present invention, a plurality of the curing agent layers are provided on the conductive adhesive film and each layer is blended with a different curing agent.

  When adopting the invention described in claim 5, it is desirable to select an optimal curing agent according to the thermosetting resin. For this reason, the hardening | curing agent layer which provided the some hardening | curing agent layer and mix | blended the hardening | curing agent optimal for resin made to each react can be provided.

  Even when one kind of thermosetting resin is employed, it may be preferable to react a plurality of curing agents in order to enhance the characteristics after curing. According to the invention described in this claim, plural kinds of curing agents can be isolated and held before being reacted, and at the same time, they can be reacted with a thermosetting resin.

  The wiring board connection step can be performed at a low temperature, and the curing agent can be uniformly applied to the thermosetting resin to be cured reliably.

It is sectional drawing of the conductive adhesive film which concerns on 1st Embodiment. It is sectional drawing which shows the outline | summary of the connection process of the wiring board using the electroconductive adhesive film which concerns on 1st Embodiment. It is sectional drawing which shows typically the state by which the isolation layer of the conductive adhesive film which concerns on 1st Embodiment is destroyed. It is sectional drawing which shows the state by which the wiring board was joined by the electroconductive adhesive film which concerns on 1st Embodiment. It is sectional drawing of the wiring board connector using the conductive adhesive film which concerns on this invention. It is sectional drawing which shows the conductive adhesive film which concerns on 2nd Embodiment. It is sectional drawing which shows the conductive adhesive film which concerns on 3rd Embodiment. It is sectional drawing which shows the conductive adhesive film which concerns on 4th Embodiment. It is sectional drawing which shows the conductive adhesive film which concerns on 5th Embodiment. It is sectional drawing which shows the conductive adhesive film which concerns on 6th Embodiment.

  Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 to FIG. 5 show an example of a conductive adhesive film according to the first embodiment of the present invention and a wiring board connection method performed using this conductive adhesive film.

  As shown in FIG. 1, a conductive adhesive film 1 according to this embodiment includes a thermosetting resin layer 2, an isolation layer 4 formed on both sides of the thermosetting resin layer 2, and the isolation layer. 4 and a hardener layer 3 laminated on the outside.

  The kind of thermosetting resin which comprises the said thermosetting resin layer 2 is not specifically limited. For example, bisphenol A type, F type, S type, AD type, or a copolymer type epoxy resin of bisphenol A type and bisphenol F type, naphthalene type epoxy resin, novolak type epoxy resin, biphenyl type epoxy resin, etc. are used. it can. Further, a phenoxy resin which is a high molecular weight epoxy resin can also be used. Moreover, in addition to the said thermosetting resin, the said thermosetting resin layer 2 can be formed by adding the additive for forming in a film shape.

  The kind of the curing agent constituting the curing agent layer 3 is not particularly limited. For example, as a curing agent, for example, imidazole series, hydrazide series, boron trifluoride-amine complex, amine imide, polyamine series, tertiary amine, alkyl urea series and other amine series, dicyandiamide series, anhydride series, phenol series, and These modified products can be employed. Moreover, these hardening | curing agent components can be used individually or in mixture of 2 or more types.

  The isolation layer 4 is made of a resin that can be isolated so that the thermosetting resin layer 2 and the curing agent layer 3 do not react at least at room temperature. Further, it is preferable to employ a resin that softens at a temperature of 100 ° C. or less and is easily broken by an acting pressure. For example, it can be formed from a resin such as a phenoxy resin, a polyvinyl butyral resin, a polyvinyl alcohol resin, or an acrylic resin.

  The conductive adhesive film can be formed using various techniques. For example, the thermosetting resin layer 2 may be formed in a film shape, the isolation layer 4 may be stacked on both sides, and the curing agent layer 3 may be stacked by coating or the like. . Or the said thermosetting resin layer 2, the isolation layer 4, and the hardening | curing agent layer 3 can be formed in a film form, and can also be laminated | stacked by lamination processing.

  The thickness of each of the layers is not particularly limited, but it is preferable to form the isolation layer 4 as thin as possible. For example, the thermosetting resin layer 2 is formed with a thickness of 20 μm, the isolation layer 4 is formed with a thickness of 3 μm, and the curing agent layer 3 is formed with a thickness of 7 μm. The total thickness of the conductive adhesive film 1 is 40 μm. Can be formed.

  Conductive particles are blended in at least one of the above layers. In the present embodiment, conductive particles (not shown) are blended in the thermosetting resin layer 2 and the curing agent layer 3.

  The material and form of the conductive particles are not particularly limited. For example, existing ones such as metal particles such as gold and nickel, and resin particles coated on a metal plating layer can be used. Moreover, a compounding quantity is not specifically limited, It can mix | blend similarly to the conventional conductive adhesive.

  Since the conductive adhesive film 1 has a configuration in which the thermosetting resin layer 2 and the curing agent layer 3 are separated by the isolation layer 4, it is not necessary to manage the thermosetting resin and the curing agent separately. . Further, by providing the isolation layer 4, the thermosetting resin and the curing agent do not react at room temperature and can be stored or transported as they are. Therefore, the handleability of the conductive adhesive is good.

  2 to 4 show an outline of a connection process for connecting the wiring board 8 and the wiring board 10 using the conductive adhesive film 1.

  As shown in FIG. 2, the first wiring board 8 is positioned and placed on the connection table 5. The wiring board 8 includes a wiring formed of a conductive film such as copper on the surface of a base material made of polyethylene naphthalate resin, and first electrodes 11a and 12a are provided in part of the wiring board 8. ing. The second wiring board 10 includes a wiring formed of a conductive film such as copper on the surface of a base material made of a polyimide resin having higher heat resistance than the first wiring board 8, and Second electrodes 11b and 12b are partially formed.

  The conductive adhesive film 1 is positioned and laminated in a connection region including the first electrodes 11a and 12a. Thereafter, the second wiring board 10 is positioned and laminated so that the second electrodes 11b and 12b are opposed to the first electrodes 11a and 12a.

  In the connection step according to the present embodiment, the heating and pressing jig 6 incorporating the heater 7 is pressed from above the connection table 5 from the second wiring board side having high heat resistance, and the first wiring This is performed by sandwiching a laminate of the plate 8, the second wiring board 10, and the conductive adhesive film 1 held between the wiring boards. The heating temperature of the heating and clamping jig 6 in the connecting step is set to 80 to 100 ° C.

  As shown in FIG. 3, when the heating and pressing jig 6 is pressed from the outer surface of the second wiring board 10, first, the curing agent layer 3 is deformed and the isolation layer 4 is deformed. Be made. Since the isolation layer 4 is formed thinner than the other layers, it is easily destroyed as shown in FIG. For this reason, the said thermosetting resin and the said hardening | curing agent are mixed and made to react with drooping of the said heating and pressing jig 6.

  Until the gap between the first electrodes 11a and 12a and the second electrodes 11b and 12b becomes 1 to 2 μm by the connection table 5 and the heating and clamping jig 6, The laminated body comprised from 10 and the electroconductive adhesive film 1 is pinched. In the connecting step, the thermosetting resin and the curing agent are mixed. Then, as shown in FIG. 4, the conductive adhesive film is cured in a state in which the first electrodes 11a and 12a and the second electrodes 11b and 12b are made conductive through the conductive particles. Thus, the wiring board connector 100 shown in FIG. 5 is formed.

  In the present embodiment, the isolation layer 4 is easily broken by being deformed by the clamping pressure acting in the connection step. For this reason, it is possible to set the temperature that acts in the connection process to be lower than the conventional conductive adhesive film that breaks the microcapsules and reacts the curing agent with the thermosetting resin depending on the temperature at which it acts. It becomes. As a result, it is possible to prevent the first wiring board having low heat resistance from being damaged by the heat acting thereon.

  In addition, the conductive adhesive film 1 according to the present embodiment has a multilayer structure in which the curing agent layer 3 is laminated on both sides of the thermosetting resin layer 2 with a separating layer 4 interposed therebetween. With this configuration, the isolation layer 4 can be destroyed, and a curing agent can be reacted from both sides of the thermosetting resin constituting the thermosetting resin layer 2. Therefore, in the connection step, the thermosetting resin can be uniformly cured by causing the curing agent to act evenly.

  For this reason, it becomes possible to reliably break the isolation layer even when the heating temperature in the connection process is low, compared with the case where the curing agent is sealed in the microcapsules that are mainly destroyed by heat, and the thermosetting The reactive resin and the curing agent can be reacted reliably. Accordingly, it is possible to further reduce the temperature acting on the wiring board in the connecting step, and it is possible to prevent the wiring board from being damaged by heat.

  Moreover, a thermosetting resin can be hardened reliably. Therefore, after removing the heating and clamping jig 6, there is no occurrence of “floating” or “returning” in which the gap between the connection electrodes is widened, and the highly reliable wiring board connector 100 is manufactured. be able to.

  FIG. 6 shows a second embodiment of the present invention. In addition, since the material which comprises the thermosetting resin layer 102, the hardening | curing agent layer 103, and the isolation layer 104 is the same as that of 1st Embodiment, description is abbreviate | omitted.

  In the second embodiment, three thermosetting resin layers 102, two curing agent layers 103, and four isolation layers 104 that isolate the thermosetting resin layer 102 and the curing agent layer 103 from each other are provided. Are provided.

  In the present embodiment, the thermosetting resin layer 102 and the curing agent layer 103 are formed with a thickness of 8 μm, and the isolation layer 104 is formed with a thickness of 2 μm. The thickness is set to 48 μm. Conductive particles are blended in the thermosetting resin layer 102 and the curing agent layer 103, respectively.

  By providing the two or more thermosetting resin layers 102 and the two or more curing agent layers 103, the thermosetting resin and the curing agent can be more uniformly mixed in the bonding step. For this reason, since hardening of a thermosetting resin is accelerated | stimulated more, it becomes possible to lower more the temperature added in a connection process.

  Moreover, it is possible to employ different thermosetting resins according to the surface characteristics of the first and second wiring boards to be joined to the thermosetting resin layers 102a and 102b on the front and back sides in FIG. Thus, it is possible to manufacture a more reliable wiring board connector.

  FIG. 7 shows a third embodiment of the present invention. In addition, since the material which comprises the thermosetting resin layer 202, the hardening | curing agent layer 203, and the isolation layer 204 is the same as that of 1st Embodiment, description is abbreviate | omitted.

  In the third embodiment, the boundary surface of each layer is formed in an uneven shape. In the present embodiment, a curing agent layer 203 is provided in the middle part, and the isolation layer laminated on both sides thereof is formed in a substantially V-shaped cross section, and the thermosetting resin layer 202 laminated on both sides. The surface is smoothly formed. The V-shaped irregularities 210 are also formed in a direction orthogonal to the paper surface, and the formation pitch is preferably set so that there are a plurality of irregularities on the electrode surface to be connected. For example, the uneven pitch can be set to 3 to 10 μm.

  The method for forming the unevenness is not particularly limited. For example, the unevenness 210 can be formed by laminating the curing agent layer 203 and the isolation layers 204, 204 in a smooth shape and then embossing the mold corresponding to the unevenness 210. .

  By forming the boundary surface of each layer in a concavo-convex shape, when the conductive adhesive film is sandwiched in the connection step, the V-shape is deformed so as to be displaced in the thickness direction, and the isolation layer is destroyed. The For this reason, it is possible to prevent the thermosetting resin and the curing agent from flowing in the surface direction. In addition, the isolation layer 204 can be destroyed uniformly over the entire bonding surface. Therefore, the thermosetting resin and the curing agent can be made to act uniformly in the surface direction, and uneven curing of the thermosetting resin can be prevented.

  The uneven shape is not particularly limited. As shown in the fourth embodiment shown in FIG. 8, the unevenness 310 having a wavy cross-sectional shape can be provided.

  FIG. 9 shows a fifth embodiment of the present invention. In addition, since the material which comprises the thermosetting resin layer 202, the hardening | curing agent layer 203, and the isolation layer 204 is the same as that of 1st Embodiment, description is abbreviate | omitted.

  In the fifth embodiment, the isolation layer 404 is provided with irregularities. In the present embodiment, unevenness is formed by providing the isolation layer 404 with a notch 410 with a small thickness.

  By providing the isolation layer with recesses and projections composed of notches, the notches 410 are easily broken when they are subjected to pinching deformation in the connecting step. For this reason, as in the third embodiment, it becomes possible to reliably destroy the isolation layer 404 in the entire area of the laminated surface of the conductive adhesive film, and to reliably react the thermosetting resin and the curing agent. It becomes possible.

  There is no particular limitation on the method for forming the concave and convex cutout 410 in the isolation layer 404. For example, it can be formed using embossing or the like as in the third embodiment. Further, the surface can be formed in an uneven shape by a sandblasting or etching technique.

  FIG. 10 shows a sixth embodiment of the present invention. In this embodiment, a thermosetting resin layer 502 is provided in the central portion, isolation layers 504 are provided on both sides thereof, and a curing agent layer 503 is provided in a predetermined pattern on the outer surface of the isolation layer 504. That is, the curing agent layer 503 is formed in an uneven shape on the surface of the isolation layer 504.

  When the conductive adhesive film having this configuration is clamped between the wiring boards in the connection step, the clamping pressure acts according to the pattern of the curing agent, and the isolation layer 504 can be more easily destroyed. For this reason, as in the above-described embodiment, it becomes possible to reliably destroy the isolation layer 404 in the entire area of the laminated surface of the conductive adhesive film, and to reliably react the thermosetting resin and the curing agent. Is possible.

  The structure of the embodiment of the present invention disclosed above is merely an example, and the scope of the present invention is not limited to the scope of these descriptions. The scope of the present invention is indicated by the description of the scope of claims, and further includes meanings equivalent to the description of the scope of claims and all modifications within the scope.

  Compared to conventional products, it is possible to connect the wiring boards at a lower temperature to manufacture a wiring board assembly, and there is no risk of the wiring board being damaged by heat, and it is cheaper using a wiring board with low heat resistance. Thus, a highly reliable wiring board assembly can be manufactured.

DESCRIPTION OF SYMBOLS 1 Conductive adhesive film 2 Thermosetting resin layer 3 Hardener layer 4 Isolation layer 8 1st wiring board 10 2nd wiring board 11a 1st electrode 12a 1st electrode 11b 2nd electrode 12b 2nd Electrode 100 Wiring board connector

Claims (6)

A conductive adhesive film that makes the electrodes provided on the wiring boards conductive by being sandwiched and deformed while being heated between the wiring boards, and forms a wiring board connector by bonding the wiring boards. ,
One or more thermosetting resin layers;
One or more curing agent layers that react and cure with the thermosetting resin;
A separating layer that separates the thermosetting resin layer and the curing agent layer;
The isolation layer is broken in the pinching deformation process and configured to react the thermosetting resin and the curing agent,
A conductive adhesive film in which conductive particles are blended in at least one of the above layers.   The conductive adhesive film according to claim 1, wherein a surface of the conductive adhesive film and / or a boundary surface of each of the layers is formed in an uneven shape.   The conductive adhesive film according to claim 1, wherein the isolation layer is formed in an uneven shape.   4. The conductive adhesive film according to claim 1, wherein the isolation layer is formed of a resin material that melts at a temperature that acts during connection. 5.   The conductive adhesive film according to any one of claims 1 to 4, wherein a plurality of the thermosetting resin layers are provided, and each layer is made of a different thermosetting resin material.   The conductive adhesive film according to any one of claims 1 to 5, wherein a plurality of the curing agent layers are provided and each layer is configured by blending different curing agents.

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