JPH0793155B2 - Heat seal connector and connection structure of this and electric circuit board - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat seal connector and a connection structure between the heat seal connector and an electric circuit board.

[0002]

2. Description of the Related Art In a conventional heat seal connector, electric circuit boards are connected only by a connecting portion of an anisotropic conductive adhesive film in which conductive particles are dispersed in a heat adhesive adhesive.

[0003]

However, in the conventional connection method, when moving after heat sealing or when inspecting,
When a force is applied in the direction of peeling the heat seal connector, there is a problem that even a slight peeling force easily causes a disconnection in the conductive line, and this occurs at a stage where the process is considerably advanced, resulting in a large loss.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems of the prior art. Even if a force is applied in the peeling direction after heat sealing, a disconnection occurs in the conductive line forming the conductive pattern. (EN) Provided is a heat-seal connector which is difficult to produce and has a high product yield, and a connection structure between the heat-seal connector and an electric circuit board.

In order to solve the above-mentioned problems, the inventor of the present invention should prevent the force from being directly transmitted to the conductive lines forming the conductive pattern even when the force is applied in the direction of peeling the heat seal connector. The present invention has been achieved as a result of various studies taking into consideration simplicity and taking into consideration simplicity, and the first invention is that a conductive pattern is formed on at least one surface of a flexible polymer film. In a heat seal connector having a connection portion covered with an anisotropic conductive adhesive film for connecting to an electric circuit board at least a part of the heat seal connector, a reinforcing member made of an electrically insulating ( resistive ) pressure sensitive adhesive is used. According to a second aspect of the present invention, there is provided a heat seal connector characterized in that the heat seal connector is provided in the vicinity of the connection portion.
The heat seal connector according to claim 1 and the reinforcing member provided in the vicinity of the connection portion of the electric circuit board are bonded to each other to connect the conductive pattern of the heat seal connector and the connection electrode of the electric circuit board. The gist of the invention is the connection structure between the heat seal connector and the electric circuit board.

One embodiment of the present invention will be described in detail below with reference to the drawings. 1A, 1B, and 1C, a conductive pattern 2 formed of conductive lines is formed on one surface of a flexible polymer film 1, and conductive particles 3 are provided on the conductive pattern 2 with a heat adhesive adhesive 4. The anisotropic conductive adhesive film 5 dispersed therein is covered. Then, the reinforcing member 7 is provided in the vicinity of the connecting portions 6 at both ends of the anisotropic conductive adhesive film 5 for connecting to the electric circuit board to be connected (portion not contributing to the connection).
The heat seal connector 8 of the present invention is formed. Figure 1
(D) shows another example of the anisotropic conductive adhesive film 5,
The conductive particles 3 are fixed only on the upper surface of the conductive pattern 2,
A heat-adhesive adhesive 4 is applied thereon to form an anisotropic conductive adhesive film 5.

FIG. 2 shows the heat seal connector 8 of the present invention.
1 shows a structure in which a connection electrode 10 as a connection portion on the electric circuit board 9 to be connected is connected. The reinforcing member 7 is bonded at a position different from the position where the electric circuit board 9 and the heat seal connector 8 are electrically connected. See also FIG.
Shows another example of the heat seal connector of the present invention, in which the anisotropic conductive adhesive film 5 is provided only on a part of the heat seal connector 8, and the reinforcing member 7 is made of the anisotropic conductive adhesive film 5. It is not provided on the upper side but is provided on the heat seal connector 8 via the insulating resin layer 11.

The flexible polymer film used in the present invention is a synthetic resin such as polyimide, polyester, polycarbonate, polyphenylene sulfide, ethylene-vinyl acetate copolymer, polymethylmethacrylate or the like, or a laminate thereof. Since these are used for electrical connection, they are not particularly limited as long as they are electrically insulating and have a volume resistivity of 10 ⁷ Ωcm or more, preferably 10 ¹⁰ Ωcm or more.

However, in consideration of temperature changeability, dimensional stability against external force, adhesion to conductive line ink and adhesive, and the like, polyester film is preferable, and its thickness is preferable from the viewpoint of flexibility and heat transfer. Is 5 to 50
μm, preferably 10 to 30 μm.

As the anisotropic conductive adhesive film, conductive particles are dispersed in a heat adhesive adhesive, or conductive particles are fixed only on the conductive pattern in advance.
The thing which apply | coated the heat adhesive adhesive may be sufficient. The heat-adhesive adhesive is not particularly limited as long as it maintains anisotropic conductivity when provided on the conductive pattern, and may be thermoplastic or thermosetting as long as it exhibits adhesiveness by heating. It may be present, but thermoplastics have the advantage that they can be bonded by heating at a relatively low temperature for a short time, and thermosettings have high bonding strength and excellent heat resistance, so pot life and bonding conditions It is appropriately selected according to (temperature, time).

As the thermoplastic resin, polyamide type, polyester type, ionomer type, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene-methacrylic acid copolymer (EM) are used.
A), ethylene-ethyl acrylate copolymer (EEA)
Examples thereof include polyolefins, various synthetic rubbers, and modified products and composites thereof. Examples of the thermosetting resin include epoxy resin, urethane, acrylic, silicone, chloroprene, and nitrile. Examples thereof include synthetic rubbers such as and the like, or a mixture thereof. In any case, a curing agent, a vulcanizing agent, a control agent, a deterioration inhibitor, a heat resistance additive, a heat conduction improver, a tackifier, a softening agent. , A colorant, etc. are appropriately added.

As the conductive particles for imparting anisotropic conductivity, metal particles such as Au, Ag, Ni, Al and Fe, metal short fibers, metal whiskers, or metal or plastic as a core and a precious metal on the surface thereof are used. Examples include plated products, carbon black, graphite powder, carbon fiber, ceramics, and the like. Graphite powder is preferable because it has high chemical stability and is inexpensive.

When the conductive particles are used by dispersing them in a heat-adhesive adhesive, if the blending amount is too small, the particles do not exist on the electrodes to be connected, causing wire breakage and increasing the resistance value. If too much, the anisotropy is stochastically connected in the plane direction and the anisotropy is impaired. Therefore, 0.1 to 30 parts by volume is preferable with respect to 100 parts by volume of the polymer copolymer as the heat-adhesive adhesive component, A more preferable range is 1 to 15 parts by volume.

When the conductive particles are fixed on the conductive pattern, the number of the conductive particles is preferably 20 or more, preferably 50 or more per 1 mm ² of the conductive pattern of the connecting portion in order to obtain a stable connection. It is better to

The conductive pattern and the anisotropic conductive adhesive film are formed by a method such as screen printing or gravure printing,
It is carried out by a method of bonding and transferring what is provided on the separator by printing, coating or the like.

Electricity for a reinforcing member provided near the connecting portion
As the insulating (resistive) pressure-sensitive adhesive, conventionally known ones can be used, such as acrylic-based, synthetic rubber-based, natural rubber-based adhesive dissolved in a solvent, paper, cloth, Examples include a method of sizing a non-woven fabric or the like impregnated with a pressure sensitive adhesive, a material such as a polymer film coated with a pressure sensitive adhesive on both sides, and sizing it to a desired size.

First, the place where the reinforcing member is provided may be either the heat seal connector or the vicinity of the connecting portion of the electric circuit board to be connected. Finally, the heat seal connector is connected to the electrical connection target by the reinforcing member of the resist type pressure sensitive adhesive. There is no particular limitation as long as the structure can be crimped onto the circuit board.

To prevent the reinforcing member from leaking between the conductive patterns, the volume resistivity of the resist pressure-sensitive adhesive is preferably 10 ⁷ Ωcm or more, more preferably 10 ¹⁰ Ωcm or more.
Any material having a resistance of Ωcm or more may be used, and the same type of heat adhesive adhesive as that used for the anisotropic conductive adhesive film may be used, or a commercially available resist ink may be used. This forming method is screen printing, gravure printing, A conventionally known method such as transfer is adopted.

[0019]

As described above, according to the heat seal connector of the present invention and the connection structure of the heat seal connector and the electric circuit, the electric circuit board to be connected to the heat seal connector by the reinforcing member in the vicinity of the connection portion is indirectly connected to the conductive pattern. Since it is adhered to the substrate, it is possible to prevent a direct force from being applied to the connecting portion and the conductive pattern in the process after the connection or the use environment after the product is completed, and it is possible to prevent the conduction failure due to the disconnection.

[0020]

Example 1 A silver paste was screen-printed on one surface of a polyethylene terephthalate film having a thickness of 25 μm to form a conductive pattern with conductive lines having a width of 0.15 mm and a pitch of 0.3 mm. Then, 7% by volume of Au-plated Ni particles having an average particle size of 20 μm with respect to the nonvolatile content are dispersed in a polyester-based heat-adhesive adhesive, and this is screen-printed on the conductive pattern to achieve anisotropic conductive adhesion. A film was formed.

After attaching a double-sided adhesive tape (volume resistivity 1.4 × 10 ¹⁰ Ωcm) with a width of 3 mm as a reinforcing member to the portions 4 mm from both ends in the longitudinal direction of the conductive pattern, the number of conductive lines is 200. Then, the heat-sealed connector of the present invention was obtained by sizing so as to have a length of 35 mm. As a comparative example, a heat seal connector without a double-sided adhesive tape attached was produced.

Using these heat seal connectors,
Under the conditions of 150 ° C, 30 kg / cm ² , and 10 seconds,
Liquid crystal display (LC
D) and the rigid printed wiring board (PCB) were adhesively connected to each other to obtain the connection structure of the present invention.

The LCD is fixed substantially horizontally with the connection surface facing downward, and a heat-sealing connector is used to weigh a P of 50 g.
Suspended the CB. LCD side amplitude 10mm, frequency 5
When the display state of the LCD was confirmed after vibrating for 1 minute at a speed of once / second, the display was normal in the example, but in the comparative example, 153 lines out of 200 lines were broken and a display defect occurred.

[0024]

As is apparent from the above-described embodiments, according to the present invention, even if a peeling direction force is applied to the connection portion in various processes after the connection of the electric circuit board and after the product is shipped, the conductive portion is electrically conductive. Since there is no disconnection of the line,
Product yield is improved and work is not particularly required, so work efficiency is improved and productivity is improved.

[Brief description of drawings]

1A is a plan view showing an embodiment of a heat seal connector of the present invention, FIG. 1B is a vertical sectional view taken along the line AA 'in FIG. 1A, and FIG. 1C is an anisotropic conductive adhesive. A longitudinal sectional view taken along the line BB 'of (a) when the dispersion type is used for the film, (d)
Is BB ′ of (a) in the case of an anisotropic conductive adhesive film obtained by fixing conductive particles on the conductive pattern of the anisotropic conductive adhesive film.
FIG.

FIG. 2 is a sectional view showing an embodiment of the connection structure of the present invention.

3A is a plan view showing another embodiment of the heat seal connector of the present invention, and FIG. 3B is a vertical sectional view taken along the line CC ′ of FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Flexible polymer film 7 Reinforcing member 2 Conductive pattern 8 Heat seal connector 3 Conductive particles 9 Electric circuit board 4 Thermal adhesive adhesive 10 Connection electrode 5 Anisotropic conductive adhesive film 11 Insulating resin layer 6 Connection part

Claims (2)

[Claims] 1. A heat seal having a conductive pattern formed on at least one surface of a flexible polymer film, and having a connection portion covered with an anisotropic conductive adhesive film for connecting to an electric circuit board on at least a part thereof. At the connector, there is no electricity
A heat-seal connector, wherein a reinforcing member made of an edge pressure-sensitive adhesive is provided in the vicinity of the connection portion. 2. The heat seal connector according to claim 1 and the reinforcing member provided near the connecting portion between the electric circuit board and the reinforcing member are adhered to each other, and the conductive pattern of the heat seal connector and the connecting electrode of the electric circuit board are connected to each other. Connection structure of heat seal connector and electric circuit board characterized by being connected.