JPH10144375A - Heat seal connector equipped with half-cut separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat seal connector which can be easily separated, has excellent connection workability, and provides highly reliable electric connection without foreign matter adhesion even in the case the outer size of the connector is small. SOLUTION: This heat seal connector 1 equipped with a half cut separator comprises a plurality of heat seal connectors 6 produced by forming a conductive circuit 3 on an insulating flexible base film 2 and forming an isotropic conductive connection means 4 such as an isotropic conductive adhesive layer on at least a connection part of the conductive circuit 3 to be connected to a substrate and a sheet-like separator 5 installed at least the connection means 4. A plurality of the heat seal connectors 6 are adjacently installed one by one and at the same time and the sheet like separator 5 has a half-cut slit continued to a boundary face of neighboring heat seal connector 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection terminal of a display such as a liquid crystal display (LCD), electroluminescence (EL), light emitting diode (LED), electrochromic display (ECD), plasma display (PDP) and the like. Connection with a circuit board equipped with a drive circuit,
Alternatively, the present invention relates to a heat seal connector used for connection between connection terminals of various electric circuit boards and the like.

[0002]

2. Description of the Related Art Conventionally, heat seal connectors have been described above.
It is used for connection between a display such as LCD, EL, LED, ECD, PDP, etc. and a hard printed wiring board (PCB), a flexible printed wiring board (FPC), or a connection between a PCB and an FPC. A conventional heat seal connector has a configuration in which a desired conductive circuit is formed on a flexible insulating base film by a conductive paste, and conductive fine particles are dispersed and mixed in the insulating adhesive. With an electrically conductive adhesive layer (JP-B-55-38073, JP-B-58-56996, etc.)
Or, in order to prevent a short circuit between adjacent terminals due to fine pitch, conductive fine particles are dispersed and mixed in advance in the conductive paste, a conductive circuit is formed by screen printing or the like, and an insulating adhesive is applied thereon. What was provided (Table 62-500)
No. 828, Japanese Unexamined Patent Publication No. Sho 62-154746, etc.) are known. These known heat seal connectors, using a cutter that cuts linearly and a die that processes curves, holes, etc., cuts and punches each separator into the desired shape,
Separated or isolated individually. At the time of connection, the separator is peeled from each heat seal connector and used.

[0003]

In the above-mentioned conventional configuration,
Since the heat-seal connectors are individually isolated, the worker separates the heat-seal connector and the separator one by one at the time of assembling and crimping (separation step), and then connects the conductive circuit terminals (hereinafter simply referred to as “separated”) of the connected board. A plurality of steps of positioning and crimping (positioning / crimping steps) were required. In addition, if the outer length and the length of the conductive circuit in the conductive circuit direction are 15 mm or less, there is a drawback that if isolated, the handleability becomes extremely poor, and the alignment work with the connected terminal becomes more difficult. Was.

In order to avoid such a drawback, the heat seal connector and the separator are separated in advance, and a plurality of the separated heat seal connectors are superimposed on each other. And the method used. This method has a problem in that, in the case of a heat seal connector using an adhesive component having a high tackiness, the superposed heat seal connectors adhere to each other and cannot be separated or become difficult. Furthermore, in this method, since the anisotropic conductive adhesive layer is in contact with the back surface of the stacked heat seal connector immediately below,
There is a drawback that foreign matter adhering to the back surface adheres to the surface of the anisotropic conductive adhesive layer and easily impairs electrical connection reliability in the module after pressure bonding.

The present invention solves the above-mentioned drawbacks of the conventional heat seal connector. Even in a heat seal connector having a small external shape, it can be easily isolated, has good connection workability, and has no foreign matter attached. It is an object of the present invention to provide a heat seal connector with high connection reliability.

[0006]

The inventor of the present invention has intensively studied the means for solving the above-mentioned problems, and as a result, particularly in the case of crimping connection of a heat seal connector having a short conductive circuit length and a small outer shape, particularly an isolation operation. In order to greatly improve the workability and positioning and crimping workability, a plurality of heat seal connectors are cut and punched to the desired outer shape on the sheet-like separator without dividing and isolating the heat seal connectors in advance. The above-described problem has been solved by adopting a configuration in which the components are aligned.

The heat seal connector with a half-cut separator according to the present invention has the following features. (A) A conductive circuit is formed on an insulating flexible base film, and at least a connection portion of the conductive circuit with a substrate to be connected is anisotropic. A heat seal connector with a separator comprising: a plurality of heat seal connectors provided with anisotropic conductive connection means such as a conductive adhesive layer; and (b) at least a sheet-like separator provided on the connection means. (C) A plurality of heat seal connectors are provided adjacent to each other, and the sheet-shaped separator has a half-cut slit connected to an adjacent boundary surface of the heat seal connector. The sheet-like separator is preferably subjected to a surface treatment so as to have a peel strength of 5 to 70 g / cm from the connection means, and has a thickness in the range of 80 to 300 μm.

In the heat seal connector with a half cut separator according to the present invention, a plurality of heat seal connectors divided and isolated by cutting and punching are arranged on a half cut (half cut) sheet-like separator. In this state, the separator is designed to have a peel strength of 5 to 70 g / cm so that the separation from the separator can be easily performed by tweezers or air suction.
Further, with the above configuration, since the separator is half-cut, there is no generation of paper powder and resin powder at the time of cutting, and the electrical conduction reliability due to the adhesion of foreign matter is not impaired. In particular, in the case of a heat seal connector having a small external dimension, a half-cut sheet-like separator has an appropriate bending strength for each heat seal connector, so-called “ Because there is a strainer, the separation work between the separator and the heat seal connector is performed by bending the separator,
The heat seal connector is easily separated from the half-cut slit.

[0009]

FIG. 1 shows an example of a heat seal connector with a half-cut separator according to the present invention. (A)
1B is a longitudinal sectional view of the heat seal connector 1 with a half-cut separator along the line XX of FIG. 1B, and FIG. 1B is a plan view. In the heat seal connector 1 with a half-cut separator according to the present invention, a conductive circuit 3 is provided on an insulating flexible base film 2 and an insulating adhesive is provided on the conductive circuit 3 as a means for connecting to a terminal to be connected. An anisotropic conductive adhesive layer in which conductive particles 4b are dispersed in 4a, that is, an anisotropic conductive connection means 4 is formed. The uppermost layer is provided with a separator 5 for preventing foreign matter from adhering and handling. In other words, the plurality of heat seal connectors 6 completely cut from the flexible base film 2 side by a cutting blade or the like and individually separated, that is, in an isolated state, are separated into half-cut sheet-like separators 5. Held on top and in alignment. In addition, at the time of cutting, in order not to cut the separator 5 completely,
It is extremely important to completely cut the heat seal connector 6 and half-cut the separator 5. This separator 5 is peeled off and used at the time of crimping connection with the terminal to be connected.

The insulating flexible base film includes polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polycarbonate (PC), polyphenylene sulfide (PPS), A heat-resistant polymer film (hereinafter simply referred to as a film) having a thickness of 10 to 50 μm selected from poly-1,4-cyclohexane dimethylene terephthalate, polyarylate, liquid crystal polymer and the like is used. The paste is printed by a known printing method such as screen printing or gravure printing to form a conductive circuit having a desired pattern. When the thickness is less than 10 μm, the film has no so-called “strain” and is extremely poor in handleability. The film thickness is 50μ
If it exceeds m, the film has high rigidity and lacks flexibility, which is not preferable.

A conductive paste for forming a conductive circuit on an insulating flexible base film is obtained by dissolving an insulating organic binder in an organic solvent and dispersing and blending a conductivity-imparting agent therewith. . Although a resin composition such as a thermoplastic resin or a thermosetting resin is used for the organic binder,
It is preferable to use a thermosetting resin in order to have heat resistance, particularly to withstand heat and pressure during connection. The conductive circuit is obtained by, for example, screen-printing the conductive paste thus obtained on a film, and then evaporating and drying the organic solvent. The thickness of the conductive circuit is 5
If the thickness is less than μm, the conductivity is poor (unstable conduction), and 20 μm
If it exceeds, the conductive circuit is likely to be broken, so that the thickness is preferably 5 to 20 μm, more preferably 10 to 15 μm.

In addition, the conductivity-imparting agent includes granules, scales,
Silver, silver-plated copper, copper, etc.
Gold, nickel, platinum, alloys thereof, resin powder plated with one or more of these metals, conductive carbon black such as conductive furnace black or channel black, or graphite powder (all One or two or more types of electronic conductivity-imparting agent) may be used, and the particle size is 0.01 to 50 μm.
It is preferably in the range of m. The conductivity-imparting agent is obtained by dispersing and blending 10 to 90 parts by weight with respect to 100 parts by weight of the organic binder, and a curing accelerator, a leveling agent, a dispersion stabilizer, an antifoaming agent, a thixotropic agent and the like are used as necessary. It may be appropriately added.

In order to firmly press-connect the heat-seal connector to the terminal to be connected, at least a connection portion on the conductive circuit of the heat-seal connector has an anisotropic conductive material in which a conductivity-imparting agent is dispersed and mixed in an insulating adhesive. It is necessary to provide an anisotropic conductive connection means such as an adhesive layer. After the crimp connection, conduction is performed in the vertical direction with respect to the conductive circuit surface, and insulation is maintained in the horizontal direction. The main ingredients of the insulating adhesive forming the connection means include ethylene-vinyl acetate copolymer (EVA), carboxyl-modified ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-isobutyl acrylate copolymer , Polyamide, polyester, polymethyl methacrylate, polyvinyl ether, polyvinyl butyral, polyurethane, styrene-butadiene-styrene (SBS) copolymer, carboxyl-modified SBS copolymer, styrene-isoprene-styrene (SIS) copolymer, styrene Ethylene-butylene-styrene (SEBS) copolymer, maleic acid-modified SEBS copolymer, polybutadiene rubber, chloroprene rubber (CR), carboxyl-modified CR, styrene-butadiene rubber, isobutylene-isoprene copolymer, nitrile rubber (NBR) , Carboxyl-modified NB It can be obtained by one kind or a combination of two or more kinds selected from R, epoxy resin, silicone rubber (SR) and the like.

Further, the above-mentioned main agent includes rosin, rosin derivative, terpene resin, terpene-phenol copolymer, petroleum resin, cumarone-indene resin, styrene resin, isoprene resin, alkylphenol resin, phenol as tackifiers. A resin or the like is appropriately added as needed, alone or in combination of two or more.

[0015] These insulating adhesive components include a curing agent, a vulcanizing agent, a control agent, a deterioration inhibitor, a heat-resistant additive, a thermal conductivity improver, a softener, a coloring agent, various coupling agents, A metal deactivator or the like may be appropriately added. Further, conductive particles are added to impart anisotropic conductivity to the insulating adhesive component. The conductive particles include metal particles such as gold, silver, aluminum, iron, and nickel; one or more selected from graphite, carbon black, ceramics, and the like, those having a noble metal plating on a metal or plastic core. And those having a particle size range of usually 1 to 50 μm are used. Means for forming an anisotropically conductive adhesive layer on a conductive circuit include, for example, a coating method such as bar coating, knife coating, roll coating and spray coating in addition to the above-mentioned known printing method. Can be adopted. This thickness is set to a thickness not exceeding the particle size range of the conductive particles. If the thickness is too large, the connection becomes unstable, and if the thickness is too small, the adhesive strength decreases.

As another anisotropic conductive connecting means provided on the conductive circuit, as shown in FIG. 2, a conductive particle 4b is fixed to a conductive circuit 3, and an insulating adhesive 4a is applied thereon. The form is also exemplified. The total thickness of the manufactured heat seal connector is 16 to 120 μm. If the thickness is within this range, it is very flexible but has very little “stiffness” and is inferior in handleability. And
In order to prevent foreign matter from adhering, a separator 5 must be provided at least on the connection means. The most important characteristic required for the separator 5 is the releasability from the heat seal connector 6, and the peel strength between the heat seal connector 6 and the separator 5 isolated by cutting and punching is 70 g / cm. If it is larger, separation becomes difficult,
If it is smaller than 5 g / cm, the heat seal connector 6 is detached from the separator 5, so that it is not less than 5 g / cm and 70 g / cm.
Or less, preferably having a peel strength of 15 g / cm or more and 60 g / cm or less.

Examples of such separators include polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polycarbonate (PC), polyphenylene sulfide (PPS), poly-1, 4- Cyclohexane dimethylene terephthalate, polyarylate, a film selected from liquid crystal polymer, or a synthetic paper or a resin-impregnated paper so as to have the above-mentioned peel strength, embossing, corona mirror finishing and foaming on the film surface. What has been subjected to release processing is used. If the thickness of the separator is less than 80 μm, when cutting the heat seal connector, there is a possibility that the separator will be cut,
The original purpose cannot be fulfilled. When the thickness is more than 300 μm, the cost of the separator itself becomes extremely high. Therefore, the thickness of the separator is 80 to 300 μm, preferably 150 to 300 μm.
It is selected from the range of 200 μm.

The heat seal connector with a half-cut separator according to the present invention having such a configuration is obtained by cutting and punching the heat seal connector from the flexible base film side with a cutting blade. At the time of cutting and punching, the cutting depth of the cutting blade is set to a depth at which the heat seal connector is completely cut and separated, and the separator is half-cut. As a result, the separator is provided with a half-cut slit (cut) continuous with the boundary surface where the heat seal connectors are adjacent to each other. The cutting depth of the cutting blade is 5% or more and 50% or less, preferably 10% or more of the thickness of the separator.
40% or less. If it is less than 5%, the cutting of the wrinkle portion of the film cannot be buffered, and the heat seal connector may not be partially cut. At 50% or more, the separator is partially cut due to the effect of the notch.

[0019]

Embodiments of the present invention will be described below with reference to examples and comparative examples. Example 1 A PET film (manufactured by Toray Industries, Inc.) having a thickness of 25 μm was used as an insulating flexible base film.
Carbon ink FC-415 as conductive paste on film
(Trade name, manufactured by Fujikura Kasei Co., Ltd.) and screen-printed to a thickness of 12 mm with a predetermined pattern with a conductor pitch of 1.0 mm.
A conductive circuit of μm was formed. In addition, SEBS
Anisotropic conductive adhesive prepared by blending 2 parts by weight of graphite particles having an average particle diameter of 20 μm with 100 parts by weight of insulating adhesive containing copolymer as a main component (total solid content),
An anisotropic conductive adhesive layer was provided by coating so that the thickness after drying became 17 μm, and a heat seal connector having a total thickness of 54 μm was produced.

Next, an average thickness of 200 μm was used as a separator.
After embossing Yupo FPG # 200 (trade name, manufactured by Oji Synthetic Paper Co., Ltd.) with one surface embossed on the entire surface of the anisotropic conductive adhesive layer on this embossed surface, the blade edge is subjected to Teflon treatment. Using the cutting blade, from the flexible base film side, while completely cutting the heat seal connector,
Cut the sheet separator to 40μm of its thickness,
Outer length (circuit direction) 6.6mm, width 33.5mm on the separator
A heat seal connector with a half-cut separator in which 50 heat seal connectors were arranged in the circuit direction continuously in a circuit direction was manufactured. The connection with the terminal to be connected using this heat seal connector with a half-cut separator was easy to handle and excellent in workability, and a good electrical connection state was obtained without adhesion of foreign matter. Table 1 shows the measurement and evaluation results for the obtained heat seal connector with a half-cut separator, together with other examples and comparative examples. The symbols ◎, 、, and × in the table indicate that the connection workability with the terminal to be connected is excellent, good, and poor, respectively.

[0021]

[Table 1]

(Example 2) A heat seal connector was manufactured in the same manner as in Example 1, and the average thickness of the heat seal connector was 2 as a separator.
After bonding Yupo FPG # 200 (trade name, manufactured by Oji Synthetic Paper Co., Ltd.) having a corona mirror-finished surface on one side to the entire surface of the anisotropic conductive adhesive layer on the corona mirror-finished surface, Example 1 A heat-seal connector with a half-cut separator of the same size was produced in the same procedure as described above. The connection with the terminal to be connected using this heat seal connector with a half-cut separator was easy to handle and excellent in workability, and a good electrical connection state was obtained without adhesion of foreign matter.

(Comparative Example 1) Average thickness as a separator
The same procedure as in Example 1 was carried out except that Toyopearl P-3155 (trade name, manufactured by Toyobo Co., Ltd.), which was a biaxially stretched polypropylene film of 65 μm, was attached to the entire surface of the anisotropic conductive adhesive layer. A heat seal connector with a half-cut separator having a size was produced, but the separator was cut to the separator when the heat seal connector was cut, and each was isolated together with the separator.

[0024]

According to the heat seal connector with a half-cut separator of the present invention, a plurality of heat seal connectors in an isolated state by cutting and punching are arranged and arranged on a half-cut separator. . Since the cut end of the heat seal connector with half-cut separator reaches the separator with a thickness of 80 to 300 μm, it does not generate paper powder or resin powder due to cutting, and the reliability of electrical connection due to foreign matter trapping Does not impair. Furthermore, since the separator is in a sheet state without being cut, it is easy to handle, and the separator is provided with appropriate bending elasticity, so-called "strain", for each heat seal connector. Even in this case, the film could be easily separated from the separator with a peel strength of 5 to 70 g / cm, and was excellent in pressure bonding workability.

[Brief description of the drawings]

1A and 1B show a heat seal connector with a half-cut separator according to the present invention, wherein FIG. 1A is a longitudinal sectional view taken along line XX of FIG. 1B, and FIG.

FIG. 2 is a longitudinal sectional view showing another embodiment of the heat seal connector with a half-cut separator of the present invention.

[Explanation of symbols]

1 ... heat seal connector with half cut separator, 2 ... flexible base film, 3 ... conductive circuit, 4 ... anisotropic conductive connecting means, 4a ... insulating adhesive, 4b ... conductive particles, 5 ... separator, 6 ... heat seal connector.

Claims (2)

[Claims] (1) A conductive circuit is formed on an insulating flexible base film, and an anisotropic conductive adhesive such as an anisotropic conductive adhesive layer is provided on at least a connection portion of the conductive circuit with a substrate to be connected. And (b) a plurality of heat-seal connectors with separators, comprising: (b) at least a sheet-like separator provided on the connection means; A heat seal connector with a half cut separator, wherein a heat seal connector is provided adjacent to each other, and the sheet-shaped separator has a half cut slit connected to an adjacent boundary surface of the heat seal connector. 2. The sheet-like separator is surface-treated so as to have a peel strength of 5 to 70 g / cm with respect to the connection means, and has a thickness in the range of 80 to 300 μm. 2. A heat seal connector with a half-cut separator according to item 1.