JPH11293206A - Winding having adhesive layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive winding-like connecting member which does not transfer to the confronting separator base and can attain very stable release of the separator base. SOLUTION: There is provided a winding consisting of a separator base 5 made of a material having a significant difference between the surface tensions on its face and back and an adhesive layer 5 formed on either of its surfaces, wherein the separator base 5 comprises at least two layers, and the surface tension on the surface on which the adhesive layer is formed is larger than that on the back surface. There are also provided a winding as described above, wherein the adhesive layer 6 contains conductive microparticles having a mean particle diameter of 1-20 μm and a winding as described above, wherein its width is 3 mm or below.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a conductive connection between a liquid crystal panel electrode and a tape carrier package (TCP) electrode, a conductive connection between a TCP electrode and a PCB (printed circuit board) electrode, a liquid crystal panel electrode and an IC bare chip. Conductive connection with the
The present invention relates to a wound body of an adhesive or a film (hereinafter, referred to as a connecting member) used for a conductive connection between a plasma display panel (PDP) and an FPC and a conductive connection between an FPC and a PCB and an IC bare chip.

[0002]

2. Description of the Related Art In recent years, as electronic components have become smaller and thinner, circuits used in them have become higher in density and higher in definition. Such electronic components are connected to fine electrodes using conventional solder, rubber connectors, or the like. Therefore, anisotropically conductive connection members having excellent resolution are often used recently. The connection member is made of an adhesive containing a predetermined amount of a conductive material such as conductive particles, and is formed on one surface of a separator base such as a polyethylene terephthalate film (PET film) or a polytetrafluoroethylene film (Teflon film). It is supplied as a roll. At this time, if the surface tension of the separator base material is the same on both sides, there is a possibility that the connection member is transferred to the facing separator base material. As a method of solving the above, it has been proposed that the surface tension of the connection member forming layer is made larger than the surface tension of the back layer by applying a silicone-based treating agent or the like to the front and back surfaces of the separator base material. In addition, a method of providing a protective film on a connection member formed on one surface of a separator base material has been proposed.

[0003]

Among the above-mentioned conventional methods, the method of providing a protective film on a connecting member formed on one side of a separator substrate requires a new protective film. Is a serious problem.
Furthermore, when used as a connection member, a step of peeling the protective film or a facility equivalent thereto is required, which complicates the operation and increases the cost of the facility. On the other hand, the method of providing a surface tension difference by performing surface treatment on the front and back surfaces of the separator base material is difficult to form a uniform treated surface state. There is a problem that the obtained releasability cannot be obtained. Also, after performing the surface treatment on the front and back of the separator substrate, the end surface of the separator substrate slit to the required width is not subjected to the surface treatment, when the connection member adheres to the end surface of the separator substrate, There are problems such as adhesion to the end face. The present invention has been made in view of such circumstances, by using a multilayer material having a superior difference in surface tension as a separator substrate, without transferring to the separator substrate facing the connecting member. It is another object of the present invention to provide a wound-shaped connection member which can provide stable peelability even when the separator base material is separated from the connection member and is inexpensive.

[0004]

According to the present invention, there is provided a rolled body in which a material having a significant difference in surface tension between the front and back surfaces is used as a separator base material, and an adhesive layer is formed on one surface, wherein the separator base material is at least formed. A wound body comprising two or more layers, wherein the surface tension of the adhesive forming surface is made larger than the surface tension of the back layer, and conductive fine particles having an average particle diameter of 1 to 20 μm in the adhesive layer. The present invention relates to a wound body having an adhesive layer characterized by being contained, and a wound body characterized by having a width of 3 mm or less. Currently, the separator base material on which the connection members actually supplied are formed has a thickness of 25 to 25.
The surface tension of the connection member forming surface is made larger than the surface tension of the back layer by applying a silicone-based treatment liquid to the front and back of a polyethylene terephthalate film having a thickness of about 100 μm. The wound body of the separator substrate on which the connecting member is formed is often slit into a width of about 1 to 20 mm depending on the application. The width of the wound body tends to be further narrowed in order to reduce the area of the connection portion, and the ratio of the area of the end face to the area of the separator base material tends to increase.

[0005] The separator substrate on which these connecting members are formed is thermocompression-bonded onto a circuit electrode such as a glass substrate or a printed circuit board, and only the connecting members are transferred onto the circuit electrodes. Is done. In FIG.
An example of the actual usage is shown. FIG.
(A) shows a state in which a separator base material on which a connection member having a required length drawn out from a wound body is formed is attached to a circuit electrode 2 on a glass substrate 1. At this time, the connection member is located on the circuit electrode side. FIG. 1B shows a step of fixing the portion pasted in FIG. 1A by thermocompression bonding. FIG.
(C) shows a step of separating the separator base material 5 from the connection member 6. At this time, the separator releasability greatly varies depending on the surface tension state of the separator substrate. In FIG.
The example in which the connection member was formed on the separator substrate of the present invention was shown. FIG. 3 shows an example in which a connecting member is formed on a conventionally used separator base material. In general, when the separator base material on which the connection member is formed is a wound body,
The surface tension of the adhesive forming surface must be greater than the surface tension of the back layer. The surface tension can be considered as an index of whether or not the adhesive layer, which is a connecting member, successfully wets the surface of the separator substrate. For example, the greater the surface tension of the separator substrate surface, the easier the adhesive layer becomes to wet,
Conversely, when the surface tension is reduced, the adhesive layer becomes difficult to wet. Therefore, when the separator substrate on which the connection member is formed is a wound body, the surface tension of the adhesive forming surface must be greater than the surface tension of the back layer, and if the surface tension of the back layer is If the value is equal to or greater than the surface tension, there is a possibility that the connection member may be transferred to the facing separator substrate.

In the conventional separator base material shown in FIG. 3, a silicon-based material or the like is applied to the front and back surfaces of the separator in order to give a superior difference between the front and back surface tensions, and the applied amount is changed to reduce the superiority difference. I am adjusting. At this time, the end face of the separator base material is not subjected to the above treatment, and when the connecting member adheres to the end face of the separator base material, the end face is adhered to the end face, or stable peelability is not obtained. There's a problem. This phenomenon is remarkably observed at a narrow width where the area ratio of the end face in the surface area of the separator substrate increases. Further, in the above-described processing method, there is a problem that the surface tension varies, and stable peelability cannot be obtained.
In order to reduce variations in the surface tension of the front and back surfaces of the separator base material, the present inventors use a material having a different surface tension without using a secondary treatment method such as surface treatment. , The variation in surface tension is suppressed.

The separator substrate of FIG. 2 shown as an example of the present invention is a film-like material having a two-layer structure of a low surface tension layer and a high surface tension layer. For example, if the low surface tension layer is made of a polypropylene material (about 28 dyn / cm) and the high surface tension layer is made of a polyethylene material (about 31 dyn / cm), an adhesive layer (about 40 to 60dyn / c
The purpose can be achieved by forming m). Separator base materials include polytetrafluoroethylene (22dyn / cm) and polyvinylidene fluoride (25dyn / c
m), polyvinyl fluoride (28dyn / cm), polypropylene (28dyn / cm), polyethylene (31dyn / cm), polytrifluorochloroethylene (31dyn / cm), polystyrene (33dyn / cm), polyvinyl alcohol (37dyn / cm) ),
Polymethyl methacrylate (39dyn / cm), polyvinyl chloride (39dyn / cm), polyvinylidene chloride (40
dyn / cm) and their modified products have a surface tension of 40 dyn / cm
The following solid polymer which forms a film is preferred. The surface tension in the above description is, for example, a critical surface tension defined by WAZisman, and may be any value as long as the surface tensions of the adhesive forming layer and the back layer are determined by the same method. The structure of the separator substrate is preferably, but not particularly limited, because a two-layer structure of a layer forming the adhesive layer and a back layer can be produced at low cost.

Next, as the adhesive as the connecting member, a material which is curable by heat or light can be widely applied. Since these are excellent in heat resistance and moisture resistance after connection, it is preferable to use a crosslinkable material. Among them, an ethoxy adhesive is preferable because it can be cured in a short time, has good connection workability, and has excellent adhesiveness in molecular structure. Epoxy adhesives, for example, high molecular weight epoxy, solid epoxy and liquid epoxy, urethane and polyester, acrylic rubber,
Generally, epoxy resin modified with NBR, nylon, or the like is used as a main component, and a curing agent, a catalyst, a coupling agent, a filler, and the like are added thereto. The conductive particles used as the conductive material in the connection member include Au, Ag, Pt, N
There are metal particles such as i, Cu, W, Sb, Sn, and solder, carbon, and the like. These conductive particles are used as a core material, or a core made of a polymer such as non-conductive glass, ceramic, plastic, or the like. A material in which a conductive layer made of the above-mentioned material is coated on a material may be used. Furthermore, it is also possible to apply insulating coated particles obtained by coating a conductive material with an insulating layer, or to use a combination of conductive particles and insulating particles. The upper limit of the particle size is preferably 15 μm or less, more preferably 7 μm or less, in order to apply to a fine electrode.
The lower limit of the particle size is 0.5 μm or more, preferably 1 μm, in order to be able to cope with the cohesiveness of the particles and the irregularities of the surface.
It should be more than that.

[0009]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Example 1 As a film-forming material, the ratio of a phenoxy resin (high molecular weight epoxy resin) to a liquid epoxy resin (epoxy equivalent 185) containing a microcapsule-type latent curing agent was 2
0/80 to give a 30% solution of ethyl acetate. In this solution, Ni / A was added to polystyrene particles having a particle diameter of 5 μm.
5% by volume of conductive particles having a metal coating with a thickness of 0.2 / 0.02 μm were added thereto and mixed and dispersed. This dispersion liquid is continuously applied to the polyethylene material side of a separator substrate (polypropylene 20 μm, polyethylene 20 μm two-layer structure) using a roll coater, dried at 100 ° C. for 10 minutes, and then an adhesive layer having a thickness of 20 μm is applied. A roll of a separator substrate thus obtained was obtained. Further, this wound body was slit in the winding direction to form a wound body having a width of 2.5 mm and a width of 0.8 mm.

Example 2 The same dispersion as in Example 1 was applied to a separator substrate (polytetrafluoroethylene 20 μm, polyvinyl fluoride 2
(2 μm two-layer structure) is continuously applied using a roll coater on the polyvinyl fluoride material side, and dried at 100 ° C. for 10 minutes to obtain a wound body of a separator base material coated with an adhesive layer having a thickness of 20 μm. Was. Further, this wound body was slit in the winding direction to form a wound body having a width of 2.5 mm and a width of 0.8 mm.

Comparative Example The same dispersion liquid as in Examples 1 and 2 was applied to a conventionally used separator substrate (a silicon-based treatment liquid was applied to the front and back of a polyethylene terephthalate film having a thickness of 40 μm to obtain a surface tension). To a low surface tension side of the film by using a roll coater,
After drying for 20 minutes, a wound body of a separator substrate to which an adhesive layer having a thickness of 20 μm was applied was obtained. Further, this wound body was slit in the winding direction to form a wound body having a width of 2.5 mm and a width of 0.8 mm.

Evaluation 1 Using the 2.5 mm wide wound bodies obtained in Examples 1 and 2 and Comparative Example, indium oxide (0.2 μm thick, surface resistance 20 Ω) was placed on a glass substrate (1.1 mm thick). / □) was affixed on the flat electrode having the thin film circuit. Paste is 80
It carried out by heating and pressurizing at -10 kgf / cm ² -3 s. As an evaluation method, the peeling force of the separator substrate was measured using a tensile tester under the conditions of a tensile speed of 50 mm / min and a tensile direction of 90 °. Table 1 shows the obtained results. As is clear from the results, when the separator substrate of the present invention was used, the conventionally used separator substrate (by applying a silicon-based treatment liquid on the front and back of a polyethylene terephthalate film having a thickness of 40 μm). It was found that stable peelability was obtained as compared with the case where the surface tension was varied.

[0013]

[Table 1]

Evaluation 2 The widths of 2.5 mm and 0.3 mm obtained in Examples 1 and 2 and Comparative Example.
After leaving the 8 mm wound body in a constant temperature bath at 40 ° C. for 1 day, 3 days, and 5 days, the separator substrate coated with the adhesive layer is pulled out at a pulling speed of 30 cm / sec, and the separator with the adhesive layer facing the separator. It was confirmed whether or not the image was transferred to the substrate (hereinafter, a blocking test). Table 2 and Table 3 show the obtained results.
Shown in A conventionally used separator substrate (a surface tension was made different by applying a silicon-based treatment liquid to the front and back of a polyethylene terephthalate film having a thickness of 40 μm) caused a failure in a blocking test. Also, this phenomenon tended to be noticeable when the width was narrow. The cause of the failure in the blocking test is that the adhesive layer flowed by being left at a high temperature and adhered to the end surface of the separator substrate that had not been subjected to the surface treatment by the silicon-based treatment liquid. In particular, when the width ratio of the end face in the surface area of the separator base material is increased to a narrow width, the releasability at the end face part cannot be maintained, and the above-mentioned problem is remarkable.
On the other hand, when the separator substrate of the present invention is used,
Good results were obtained and were satisfactory.

[0015]

[Table 2]

[0016]

[Table 3]

[0017]

According to the present invention, by using a material in which the surface tension of the adhesive forming layer is smaller than the surface tension of the back layer as the separator base material, the transfer member is not transferred to the separator base material facing the connecting member. In addition, it is possible to provide an inexpensive wound-shaped connecting member capable of obtaining extremely stable releasability of the separator substrate.

[Brief description of the drawings]

FIGS. 1A, 1B, and 1C are conceptual diagrams showing examples of use of a separator base material on which connection members are formed.

FIG. 2 is a cross-sectional view showing an example in which a connection member is formed on a separator substrate of the present invention.

FIG. 3 is a cross-sectional view showing an example in which a connection member is formed on a conventional separator base material.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Circuit electrode 3 Separator base material on which connection member was formed 4 Pressurized heating head 5 Separator base material 6 Connection member 7 High surface tension layer 8 Low surface tension layer 9 Silicon processing surface (processing maximum) 10 Silicon system Processing surface (minimum processing)

Claims (3)

[Claims] 1. A wound body comprising a separator base material made of a material having a superior difference in surface tension between the front and back surfaces, and an adhesive layer formed on one surface, wherein the separator base material comprises at least two layers. A wound body characterized in that the surface tension of the formation surface is made larger than the surface tension of the back layer. 2. The wound body according to claim 1, wherein the adhesive layer contains conductive fine particles having an average particle diameter of 1 to 20 μm. 3. The wound body according to claim 1 or 2,
A wound body having a width of 3 mm or less.