JP2994796B2 - Manufacturing method of low resistance elastic connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a liquid crystal display panel (LC).
D panel) and a printed wiring board (PC board).
In particular, the present invention relates to an improved method for manufacturing a low-resistance elastic connector in which a four-layer body obtained by sequentially joining a metal thin film layer, a carbon resin layer, a conductive elastomer layer, and an insulating elastomer layer is repeatedly laminated as a repeating unit.

[0002]

2. Description of the Related Art A low-resistance elastic connector 1 developed for a large LCD panel, particularly a simple matrix large LCD panel for displaying a gradation image, is shown in FIG.
As shown in (b), a metal thin film layer 2, a carbon resin layer (CR layer) 3, a conductive elastomer layer (conductive SR layer) 4
And a four-layer body obtained by sequentially joining the insulating elastomer layer (insulating SR layer) 5 as a repeating unit, and the connection with the terminal electrode to be connected is performed by surface contact of the conductive SR layer 4, The inside of the connector is a metal thin film layer 2 through a CR layer 3.
Forms a short-circuited conductive path, so that the resistance can be reduced to a fraction of that of a so-called zebra connector in which only a conventional conductive SR layer and an insulating SR layer are repeated.
Specifically, it is very useful because an LCD panel having a terminal electrode pitch of about 0.3 mm and a PC board can be connected with a resistance value of 100Ω or less per terminal electrode. The elastomer is not particularly limited as long as it is a conventionally known elastomer. In general, a silicone rubber is used, and the silicone rubber will be described below as an example.

As shown in FIG. 3, a conventional method of manufacturing this low-resistance elastic connector is to form a thin release layer 8 such as a silicone resin for release paper on one surface of a base film 7 such as a PET (polyethylene terephthalate) film. Al, Cu, Sn, C on the release layer surface of the release sheet 9
r, Ni, vacuum deposition a metal such as Au, cathode sputtering or the like, to form a thickness of several hundred Å, surface resistivity 10 ⁰ Ω / □ before and after the metallic thin film layer 2. The polyurethane on the upper surface of the metallic thin film layer 2 or the like mixed with carbon black in a resin solution in a solvent, the volume resistivity after drying of 10 ⁰
Using a coating machine such as a gravure coater or a roll coater, the carbon resin ink of about Ω · cm is coated and dried to form a CR layer 3 having a thickness of several μm.
To form At this time, the combined surface resistance of the CR layer / metal thin film layer is 10Ω / □ at the maximum, and when the connector is used, this composite layer ultimately contributes to low-resistance conduction. Next, the addition type vulcanization type conductive S
The R layer 4 is divided so as to have a thickness of more than 20 μm, and topping is performed on the upper surface of the CR layer 3 by using the mat-shaped fine irregularities on the surface of the CR layer (note; Is performed by simultaneously passing rubber through a mat sheet and a thin rubber layer, and pressing and covering the rubber on the mat sheet), and several times in a normal pressure hot air vulcanization tank (HAV furnace) at a temperature of 200 ° C to 400 ° C. Allow to cure for 10 seconds. The conductive SR layer 4 generally has a volume resistivity of about 1 Ω · cm. Next, the additional type vulcanized insulating SR layer 5 is again separated by a calender roll so as to have a thickness of more than 20 μm, topped on the surface of the conductive SR layer 4, and retained in the process in an unvulcanized state. . On the release sheet 9 thus obtained, the metal thin film layer 2,
The release layer 9 is peeled off from the five-layer body obtained by joining the CR layer 3, the conductive SR layer 4, and the insulation SR layer 5 in this order, and the four-layer body is laminated in multiple layers. The layer 5 is vulcanized, and the four-layered body is repeatedly united to form a laminated block by laminating multiple layers, and the laminated block is sliced at a thickness Z perpendicular to the laminating direction. Silicone rubber is adhered as the support insulating material 6, cut, and the low-resistance elastic connector 1 having a predetermined width W, height H, and length L is obtained. This connector has an LCD panel and a PC board having a conductive layer arrangement pitch of about 50 μm and a terminal electrode pitch of about 0.3 mm.
Connection can be made with a resistance value of 100Ω or less per terminal electrode.

[0004]

[0005] However, the above 4)
The layer body has a problem that it has low mechanical strength and is difficult to handle. That is, a metal thin film layer having a thickness of several hundreds of
The strength of the CR layer and the unvulcanized insulating SR layer is low, and the mechanical strength of the four-layer body is maintained by the vulcanized conductive SR layer having a thickness of about 20 μm. In the process, when the release sheet is peeled off, the release sheet is easily torn from the end. Wrinkles are easy to form and it is difficult to laminate while obtaining a flat surface. Since the four-layer body has a thickness of only 50 μm, in order to obtain a connector having a length L of 250 mm, it is necessary to laminate as many as 5,000 layers, which is disadvantageous in that it takes too much work. . The present invention maintains the same configuration of repeating a four-layer body in which a metal thin film layer, a CR layer, a conductive SR layer, and an insulating SR layer are sequentially joined,
It is an object of the present invention to increase the vulcanized rubber layer in the laminated unit to improve the mechanical strength and to make the manufacturing workability of the connector easier.

[0005]

The production method of the present invention achieves the above-mentioned object. This method comprises repeating a four-layer body in which a metal thin film layer, a CR layer, a conductive elastomer layer and an insulating elastomer layer are joined in this order. In a method of manufacturing a low-resistance elastic connector in which multiple units are laminated, a metal thin film layer, a CR layer, a conductive elastomer layer, and an insulating elastomer layer are sequentially joined on a first release sheet to form a five-layer body. A CR layer and a metal thin film layer are sequentially bonded on the second release sheet to form a three-layer body, and the three-layer body is inverted on the uppermost layer of the five-layer body to form a three-layer body. Joining to form an eight-layer body, then removing the second release sheet, forming a conductive elastomer layer and an insulative elastomer layer in that order to form a nine-layer body, and then forming the first release sheet The eight-layer body obtained except for A low resistance elastic connector manufacturing method, which comprises laminating and integrating the multiple is for summarized as.

An example of the manufacturing method of the present invention will be described below with reference to the drawings. The five-layer body formed on the first release sheet 9 is adjusted in the same manner as in the prior art. That is, first,
As shown in FIG. 1A, a metal thin film layer 2 is formed on an upper surface of a first release sheet 9 , and a carbon resin ink is coated on the upper surface using a coating machine and dried to form a CR layer 3. Form. Next, the conductive SR layer 4 is separated into a predetermined thickness by a calender roll, topped on the surface of the CR layer 3, and heated at a temperature of 300 ° C. to 400 ° C.
Vulcanize by passing through an AV furnace for several tens of seconds. Next, insulation S
The R layer 5 is separated, topped on the surface of the conductive SR layer 4 and retained in the process in an unvulcanized state. Thus, on the first release sheet 9 , a five-layer body in which the metal thin film layer 2, the CR layer 3, the conductive SR layer (vulcanized) 4, and the insulating SR layer (unvulcanized) 5 are formed in this order is prepared. It will be.

[0007] Next, as shown in FIG. 1 (b), a second release sheet 19 comprising a base film 17 and a release layer 18.
A carbon resin ink is coated on the upper surface of the substrate with a coating machine and dried to form a CR layer 13. An Al metal thin film layer 12 is formed on this upper surface by using a vacuum evaporation apparatus. Next, as shown in (c), the insulating SR layer (unvulcanized) 5 on the uppermost surface of the five-layer body formed on the first release sheet 9 and the second release sheet 19 The formed three-layer body is inverted, the topmost metal thin film layer 12 is overlapped, passed through the pressure roll 10 and brought into close contact, and the temperature is reduced to 30.
Pass the HAV furnace at 0 to 400 ° C for several tens of seconds to isolate the SR.
At the same time that the layer 5 is vulcanized, it is bonded and integrated with the metal thin film layer 12, and the second release sheet 19 is peeled off in a subsequent step.
After all, on the first release sheet 9 , the metal thin film layer 2, the CR layer 3, the conductive SR layer (vulcanized) 4, the insulating SR layer (vulcanized)
5, a seven-layer body formed in the order of the metal thin film layer 12 and the CR layer 13 was prepared.

[0008] Next, the conductive SR
Into a predetermined thickness, and as shown in FIG.
The top surface of the topmost CR layer 13 of the seven-layer body formed on the release sheet 9 is vulcanized by passing through a HAV furnace at a temperature of 200 ° C. to 400 ° C. for several tens of seconds to cure the conductive SR layer 2.
4 and then calender rolls are used to insulate SR
The layer 25 is separated, topped on the upper surface of the conductive SR layer 24, and retained in the process in an unvulcanized state.

After all, on the first release sheet 9 , the metal thin film layer 2, CR layer 3, conductive SR layer (vulcanized) 4, insulating SR layer (vulcanized) 5, Al metal thin film layer 12, This means that a nine-layer body in which the CR layer 13, the conductive SR layer (vulcanized) 24, and the insulating SR layer (unvulcanized) 25 are sequentially formed is prepared. Here, the cured conductive SR layer and the insulating SR layer are three layers in total, and if each layer has a thickness of 20 to 25 μm, it has a thickness of 60 to 75 μm. become.

Next, the first release sheet 9 is peeled off from the nine-layer body, and the remaining eight-layer body is laminated in multiple layers, and the insulating SR layer (unvulcanized) 25 is vulcanized by press molding. Integrate the laminated blocks. In the subsequent process, ie, slicing the laminated block, supporting insulation S on both sides of the slice sheet
Steps such as providing the R layer 6 and cutting the height H and the length L to predetermined dimensions are performed in the same manner as the above-described conventional method.
A low-resistance elastic connector 1 as shown in FIGS.

The first and second release sheets are formed by forming a thin release layer such as a silicone resin for release paper on one surface of a base film such as a PET film. A resin solution obtained by dissolving polyurethane or the like in a solvent as described above can be obtained by coating and drying a carbon resin ink containing carbon black. Since the CR layer is a material harder than the elastomer layer, the thinner the better, the more the thickness is, the more the press-contact stress when the connector is formed becomes too large. Good to do. Further, the volume resistivity of the CR layer is preferably as low as possible, and if it is too high, conduction between the conductive elastomer layer and the metal thin film layer is hindered. It is preferable to set the range of about 2 to 3 Ω · cm.

Each metal thin film layer in the present invention can be formed by a vacuum deposition method, a cathode sputtering method, or the like. The types of metals are Al, Cu, Sn, Cr, and N.
i, Au, Ag, Pt, Zn, Fe, Mn, Mo, T
i, W, etc., but use of an Al vacuum deposited film is the most common. The thickness of this Al vacuum deposited film is 100 to 1
It is good to be in the range of 000 °, preferably in the range of 300 to 800 °. The surface resistance of this Al vacuum deposited film is 1 to 1.5 Ω / □ at a film thickness of 600 to 800 °.

The materials of the conductive elastomer layer and the insulating elastomer layer in the present invention are natural rubber (NR), butadiene rubber (BR), styrene rubber (SBR), chloroprene rubber (CR), nitrile rubber (NBR), butyl rubber. (IIR), ethylene propylene rubber (EPD)
M), fluoro rubber (FKM), silicone rubber (SR)
And thermoplastic elastomers such as styrene-butadiene-styrene copolymers. The ease of obtaining conductivity by kneading carbon black, environmental reliability, and the use of 20 as an elastic connector material for LCD
Silicon rubber (S
R) is most preferred. The thickness of the conductive elastomer layer and the insulating elastomer layer is naturally determined by the conductive layer arrangement pitch of the connector, and since the pitch of the conventional elastic connector is about 50 μm, the thickness of the CR layer (5 μm or less) is reduced. It is selected from about half thereof, that is, from 15 to 25 μm. The volume resistivity of the conductive elastomer layer is preferably as low as possible, and if it is too high, the conduction resistance of the connector is not different from that of the conventional product.
Within the range of 10 to 10 Ωcm, practically 0.5 to 1.5 Ωcm
cm.

[0014]

[Example] PET film with release layer (thickness 75 μm)
A carbon black was kneaded into a polyurethane resin solution on an Al-deposited thin film surface of an Al-deposited transfer film having an Al vacuum-deposited thin film having a thickness of 800 mm and a surface resistance of 0.5 Ω / □. A Ω · cm carbon resin ink, ST-77-61 Rev. I (trade name, manufactured by Shin-Etsu Polymer Co., Ltd.) was coated with a gravure coater and dried to form a CR layer having a thickness of 5 μm. This C
The surface resistance of the composite of the R layer and the Al vapor-deposited thin film layer was measured and found to be 3.5 Ω / □.

Next, an additional type vulcanization type conductive S having a volume resistivity of 0.9 Ω · cm and a hardness (JIS-A) of 65 ° Hs.
The R layer was separated by a calender roll to a thickness of 20 μm, topped on the CR layer surface, and heated in a HAV furnace at 260 ° C. for 30 minutes.
Vulcanized by passing for 2 seconds. Further, the volume resistivity 10
⁺¹⁴ Ω · cm, hardness (JIS-A) 70 ° Hs, additional type vulcanization type insulating SR layer is divided into 25 μm thickness, topped on the surface of the conductive SR layer, and retained in an unvulcanized state. Was. As a result, a five-layer body including the first release sheet was obtained.

On the other hand, a carbon resin ink, ST-77-61 Rev. I (described above) is coated on a 75 μm-thick PET film with a release layer (second release sheet), dried, and dried. A CR layer having a thickness of 5 μm was formed. On top of this,
800mm thick by vacuum evaporation method, surface resistance 0.5Ω / □
Was formed. The two layers on the second release sheet are inverted and stacked on the uppermost surface of the five-layer body including the first release sheet while degassing with a pressure roll.
The insulating SR layer (unvulcanized) was vulcanized by passing through an AV furnace for 20 seconds, and then the second release sheet was peeled off. As a result, a seven-layer body including the first release sheet was obtained.

Next, the conductive SR layer is fractionated by a calender roll to a thickness of 20 μm, and the conductive SR layer including the first release sheet 7
Topping on top of layer (CR layer side), 260 ° C
For 30 seconds to cure. further,
The insulating SR layer was separated to a thickness of 25 μm, topped on the surface of the conductive SR layer, and retained in an unvulcanized state to obtain a nine-layer body including the first release sheet.

The nine-layer body including the first release sheet is cut into a size of 250 mm × 250 mm together with the release sheet, and the first release sheet is peeled off using a laminating apparatus. A 9-layer body is laminated 2500 times,
Press molding was performed under the conditions of 0.8 kgf / cm ² × 24 hours to obtain an integrated laminated block. Next, the slicer is sliced in parallel with the laminating direction by a connector slicer, and the conductive layer arrangement pitch is 50 μm × thickness 0.7 mm × □ 250 mm.
Was prepared. On both sides of this sliced sheet, hardness (JIS-
A) An insulating SR layer of 30 ° Hs and SS-30 (trade name, manufactured by Shin-Etsu Polymer Co., Ltd.) are stacked, and 160 ° C. × 0.8 kgf
/ Cm ² × 10 minutes, press cure integrated, width (W) 5 mm × height (H) 8 mm × length (L) 250 m
m to complete a low-resistance elastic connector.

[0019]

According to the present invention, the metal thin film layer, CR
Layer, conductive elastomer layer (vulcanized), insulating elastomer layer (vulcanized), metal thin film layer, CR layer, conductive elastomer layer (vulcanized), insulating elastomer layer (unvulcanized)
By using the eight layers as a lamination unit, the conventional problems are solved, the lamination process is facilitated, and the productivity of this low-resistance elastic connector can be greatly increased.

[Brief description of the drawings]

FIGS. 1 (a), (b), (c) and (d) are explanatory views of the steps of the manufacturing method of the present invention.

FIG. 2A is a perspective view of a conventional low-resistance elastic connector, and FIG. 2B is a partial longitudinal sectional view taken along line XX of FIG.

FIG. 3 is a longitudinal sectional view of a repeating unit provided with a release sheet when a conventional elastic connector is manufactured.

DESCRIPTION OF THE SYMBOLS 1 Low-resistance elastic connector according to the manufacturing method of the present invention 2, 12 Metal thin film layer 3, 13 Carbon resin layer 4, 24 Conductive elastomer layer 5, 25 Insulating elastomer layer 6 Support insulating material 7, 17 Base Film 8, 18 Release layer 9 First release sheet 19 Second release sheet 10 Pressure roll

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-55774 (JP, A) JP-A-2-126578 (JP, A) JP-A-62-151111 (JP, A) (58) Investigation Field (Int.Cl. ⁶ , DB name) H01R 43/00 H01R 11/01

Claims (1)

(57) [Claims] In a method for manufacturing a low-resistance elastic connector, a four-layer body in which a metal thin film layer, a carbon resin layer, a conductive elastomer layer and an insulative elastomer layer are sequentially joined is repeatedly formed as a repeating unit. A metal thin film layer, a carbon resin layer, a conductive elastomer layer, and an insulating elastomer layer are sequentially joined on the
A layered body is formed, and a carbon resin layer and a metal thin film layer are sequentially bonded on a second release sheet to form a three-layered body.
On the uppermost layer of the layered body, the three-layered body is inverted and its metal thin film layer is joined to form an eight-layered body. Then, the second release sheet is removed, and a conductive elastomer layer and an insulating layer are formed thereon. A low-resistance elastic connector characterized in that after forming a nine-layer body by sequentially forming a conductive elastomer layer, an eight-layer body obtained by excluding the first release sheet is repeatedly laminated and integrated as a repeating unit. Method.