JPS6252869A - Film-like connector and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a film-like connector and a method for manufacturing the same, and more particularly, it relates to a film-like connector and a method for manufacturing the same. The present invention relates to a film-like connector used when connecting, etc., and a method for manufacturing the same.

Conventional technology Conventionally, this type of film-like connector has (1)
A thin plate-like connector made by laminating a large number of conductive rubber thin plates and insulating rubber thin plates alternately glued together and cutting them thinly in a direction perpendicular to the plane of the thin plates; (2) Flexible thin conductor wires; There are flexible film-like connectors, etc., which are made by arranging a large number of molded products embedded in a parallel polymeric insulating material and cutting them thinly in parallel to the arrangement surface.

Problems to be Solved by the Invention However, the above-mentioned side connectors also have their own problems. That is, in the connectors (1) and (2) above, the manufacturing process is complicated and requires precision, resulting in high costs, and in the connector (3) above, there are problems such as irregular conductor particles. There were problems such as variations in conductivity and low reliability.

As a solution to this problem, (4) a conductive circuit/pattern is printed by screen printing using a conductive paste on an insulating base film, and the other parts of the conductive circuit pattern are also registered by screen printing. A film-like connector has been proposed, which is made by printing a heat-melt adhesive on the film.

However, this connector also has the following various problems. That is, it is difficult to perform the registration with high precision, and since the conductive circuit pattern is formed using conductive paste, it is difficult to obtain a low resistance with no variation in resistance value due to material problems. However, since the hot-melt adhesive is applied only to areas other than the conductive circuit pattern, there is a problem with adhesive strength, and the conductive circuit pattern is also formed by printing. There have been problems, such as the fact that there is a limit to the conductor line width, making it difficult to accurately form fine conductive circuit patterns.

An object of the present invention is to provide a flexible film-like connector in which a fine conductive circuit pattern having good electrical properties is formed with high accuracy, and to provide a method for easily manufacturing the film-like connector. There is a particular thing.

A means to solve the problem, that is, a film connector according to the present invention is a laminate in which a conductive photoresist pattern layer is provided on an electrically conductive metal thin film pattern layer on an insulating base film. A conductive circuit pattern section is formed thereon, and a hot-melt adhesive layer having anisotropic conductivity is formed on the surface on which the conductive circuit pattern section is formed. However, the method for producing a film connector according to the present invention involves forming a conductive metal thin film layer on the entire surface of an insulating base film, and then depositing a conductive metal thin film layer thereon, which has a conductive etching resist function. Forming a resist layer on the entire surface, then using photofabrication technology to make the photoresist layer into a photoresist pattern layer exhibiting a predetermined shape, and etching the metal thin film layer using the hindlimb photoresist pattern layer as an etching resist. forming a metal thin film pattern layer corresponding to the photoresist pattern layer, forming a laminate of the metal thin film pattern layer and the photoresist pattern layer to form a conductive circuit pattern portion, and forming the corresponding hindlimb conductive circuit. The method is characterized in that a hot-melt adhesive layer having anisotropic conductivity is formed on the surface on which the pattern portion is formed.

Function: In view of the problems that conventional products have mentioned above, the inventor of the present invention has developed this product after conducting various researches, and has developed the photofabrication technology as a method for forming conductive circuit patterns for connectors. By skillfully applying metal thin film forming technology, all of the above problems can finally be solved.

Example Hereinafter, the present invention will be explained in detail using the drawings.

First, the structure of the film connector according to the present invention will be explained.

FIG. 1 is a sectional view of a film-like connector according to the present invention, in which 1 is an insulating base film, 2 is a conductive metal thin film pattern layer, 3 is a conductive photoresist pattern layer, and 4 is a different 6 is a conductive circuit pattern portion made of a laminate of the metal thin film pattern layer 2 and the photoresist pattern layer 3.

Next, each constituent layer will be explained in more detail while explaining an example of a method for manufacturing a film-like connector having such a structure.

FIG. 2 to FIG. 6 are cross-sectional views showing the manufacturing process of the film-like connector according to the present invention.

First, a conductive metal thin film layer 2' is formed on the entire surface of the insulating base film 1.

The insulating base film 1 according to the present invention may be a flexible film made of a single film or a composite film such as a polyester film, a polyimide film, a polycarbonate film, a polyether sulfur film, a Holisal 7t film, or a polyenylene oxide film. At the same time, a plastic film or the like which has excellent dimensional stability and electrical insulation properties can be used. The film thickness is suitably in the range of 12 μm to 100 μm. When the thickness becomes thinner than 12 μm, the dimensional stability decreases and it becomes difficult to handle foam.
This is because if the thickness becomes too thick, there will be problems in use in terms of flexibility.

This insulating base film 1 may be subjected to corona discharge treatment, chemical treatment, etc., or may be coated with a single layer of primer in order to increase the adhesion strength with the conductive metal thin film layer 2', which will be described later. It is preferable to use Furthermore, it is also possible to use a material whose back surface has been coated to prevent curling.

The conductive metal thin film layer 2' according to the present invention is made of a single metal such as gold, silver, copper, aluminum, or nickel, or an alloy of these metals, or indium oxide.

Using metal oxide such as tin oxide, the film thickness is 1oOλ~6o
It is formed within a range of people.

The method for forming the metal thin film layer 2' includes vacuum evaporation,
There are sputtering methods, CVD methods, chemical plating methods, etc.

Incidentally, the metal thin film layer 2' having such conductivity may be formed as two or more layers of different metal materials obtained by appropriately combining the metals, alloys thereof, or metal oxides. This is to obtain excellent electrical properties and excellent quality stability at the same time. For example, gold, silver, and copper, which are low-resistance metal materials.

It may be formed by appropriately combining a metal material such as aluminum with a metal material having high stability against humidity, temperature, and air such as nickel, tin, indium oxide, or tin oxide.

Next, a conductive photoresist layer 3' is formed over the entire surface of the conductive metal thin film layer 2' formed on the insulating base film 1. As a photoresist material that can be used for this purpose, commercially available photopolymers for metal etching have a particle size of 0.5 μm to 1 μm.
conductive powders such as carbon black, graphite, gold, silver.

Glass powder whose surface is coated with metals such as copper and nickel, metal powders such as gold, silver, copper, and nickel, and metal oxide powders such as indium oxide and tin oxide in a composition ratio of 15 wt% to 8.
There are photopolymers added at 0 wt% or photopolymers that themselves have conductivity.

The conductive powder added to the photopolymer includes:
In order to prevent reflection or absorption of ultraviolet rays during photocuring or photodecomposition of the photopolymer, it is preferable to use a transparent powder of a metal oxide such as indium oxide or tin oxide. The photopolymer used as the dispersion medium for the conductive powder is preferably a photoelastic polymer, since if the film after photocuring is too hard, the original flexibility of the base film will be lost.

The conductive photoresist layer 3' can be formed directly on the metal thin film layer 2' by a coating method, a printing method, etc., or it can be formed by a coating method, etc. on a carrier film prepared separately in advance. Then, there is a method in which a photoresist layer on this carrier film is laminated on the metal thin film layer 2'. The film thickness of the photoresist layer 3' is 3 μm to 60 μm,
Preferably, the thickness is in the range of 3 μm to 16 μm.

By the above method, an electrically conductive metal thin film layer 2' and an electrically conductive photoresist layer 3 are applied to an insulating base fill.
2 shows a cross-sectional view of the structure.

Next, the seven photoresist layers 3' are exposed to light through a photomask 6 having a predetermined shape, and the photoresist layers 3' are selectively baked, photocured or photodecomposed (see FIG. 3).

Next, development is carried out by dissolving and removing the 7 photoresist layers in the unexposed or exposed areas (see FIG. 4).

By doing so, a conductive photoresist pattern layer 3 having a predetermined shape can be formed.

Thereafter, the metal thin film layer 2' is etched using the conductive photoresist pattern layer 3 as an etching resist (see FIG. 5).

By doing this, the metal thin film pattern layer 2 has a shape that matches the photoresist pattern layer 3.
The conductive circuit pattern portion 6 can be formed by laminating the metal thin film pattern layer 2 and the photoresist pattern layer 3.

The enoching step can also be performed by wet treatment, dry treatment, or the like.

After the etching process is completed, a hot-melt adhesive layer 4 having anisotropic conductivity is formed (see FIG. 1).

This hot-melt adhesive layer 4 may be formed to cover the entire surface of the conductive circuit pattern portion 6, or may be formed to cover at least only the portion connected to the other electrode. . The method for forming the hot melt adhesive layer 4 is as follows:
It can be formed directly on the surface on which the conductive circuit pattern portion 6 is formed by a coating method, a printing method, etc., or it can be formed by a coating method, etc. on a carrier film prepared separately in advance, and the heat on this carrier film can be applied. There is a method of laminating a meltable adhesive layer on the surface on which the conductive circuit pattern portion e is formed.

The hot-melt adhesive layer 4 having anisotropic conductivity can be formed using a hot-melt adhesive to which conductive powder is added, and is used by adding it to the hot-melt adhesive layer 4. Examples of conductive powders to be used include carbon, gold, silver, copper, nickel, tin oxide, indium oxide, etc., and hot-melt adhesives for dispersing them include vinyl acetate, vinyl, acrylic, and wax. General hot-melt adhesives such as polyolefin, polyamide, synthetic rubber, etc., either singly or in combination, can be used. The rate of dispersion is determined by adjusting it appropriately to the extent that the hot-melt adhesive layer 4 exhibits anisotropic conductivity. For example, when using a power pump rack as a conductive powder, hot melt adhesive 10
The range of 01 to 10 parts by weight is preferable relative to 0 parts by weight.

This is because when the amount added is less than 0.1 parts by weight, the number of carbon black particles sandwiched between the conductive circuit pattern part e and the mating electrode described later decreases, and the effect as a connector is not obtained. K<<, and if it exceeds 10 parts by weight, the hot-melt adhesive layer 4 itself becomes conductive;
This is also because the effect as a connector cannot be obtained. The layer thickness of the hot-melt adhesive layer 4 is 1 to 100 μm.
is preferred.

If this is less than 1 μm, the adhesive force will decrease, and 100
This is because if it exceeds .mu.m, there is a possibility of poor conduction.

By doing as described above, a film-like connector according to the present invention can be obtained.

When using the film-like connector obtained as described above, the conductive circuit pattern portions 6 are stacked facing each other at positions corresponding to the transparent electrode portions 8 provided on the glass substrate 7, for example. Heat press (see Figure 6). By doing so, the conductive powder in the hot-melt adhesive layer 4 is interposed between the conductive circuit pattern part 6 of the connector and the transparent electrode part 8 on the glass substrate T, and electrical continuity is achieved. At the same time, the hot melt adhesive layer 4
The conductive circuit pattern section 6 and the transparent electrode section 8 are easily crimped together by the melt adhesive action of the conductive circuit pattern section 6 and the transparent electrode section 8, thereby achieving the effect of a connector.

It goes without saying that the film-like connector according to the present invention can be applied to connections other than the above-mentioned transparent electrode.

Effects of the Invention Since the present invention has the above configuration,
This has the following effects. That is, since the conductive circuit pattern portion is formed by applying the 7-off-1 application technique, it is possible to easily form a fine and highly accurate conductive circuit pattern. Further, since the metal thin film pattern layer having a low resistance value is used as one of the constituent layers of the conductive circuit pattern portion, a conductive circuit pattern having good electrical characteristics can be obtained. Furthermore, since the conductive circuit pattern part is connected to the other electrode by the melting adhesive action of the hot-melt adhesive, perfect adhesion is achieved and there is no risk of poor conductivity due to long-term use. It can be connected reliably. Therefore, when this is used as a connector, it has extremely excellent quality. Furthermore, the manufacturing process is simple and extremely economical, and the industrial value is extremely high.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a film-like connector according to the present invention;
2 to 6 are cross-sectional views showing the manufacturing process of the film-like connector according to the present invention, and FIG. 6 shows the connection between transparent electrodes provided on a glass substrate using the film-like connector according to the present invention. FIG. 1...Insulating base film, 2...Metal thin film pattern layer having conductivity, 2'-...Metal thin film layer having conductivity, 3...・Photoresist pattern layer having conductivity, 3<...Photoresist layer having conductivity, 4...Hot melt adhesive layer having anisotropic conductivity, 5... ...Photomask, 6... Conductive circuit pattern section, 7...
-Glass substrate, 8...Transparent electrode part. Name of agent: Patent attorney Toshio Nakao and 1 other person
1 Figure 1 - 41 small units in one boat, 4 no.

Claims (14)

[Claims] (1) A conductive circuit pattern portion is formed on an insulating base film, and is composed of a laminate in which a conductive photoresist pattern layer is provided on a conductive metal thin film pattern layer, and the conductive circuit pattern 1. A film-like connector characterized in that a heat-melt adhesive layer having anisotropic conductivity is formed on the surface on which the part is formed. (2) The film-like connector according to claim 1, wherein the insulating base film is a surface-treated plastic film. (3) The film-like connector according to claim 1 or 2, wherein the conductive metal thin film pattern layer is formed using a metal or a metal oxide. (4) The metal thin film pattern layer having conductivity is formed as two or more layers of different metal materials, according to any one of claims 1 to 3. Film connector. (5) The photoresist pattern layer having conductivity is formed using a photopolymer to which conductive powder is added. The film-like connector described. (6) According to any one of claims 1 to 4, wherein the conductive photoresist pattern layer is formed using a photopolymer that itself has conductivity. The film-like connector described. (7) The hot-melt adhesive layer having anisotropic conductivity is formed using a hot-melt adhesive containing conductive powder. 6th
The film-like connector described in any of the above. (8) A conductive metal thin film layer is formed on the entire surface of the insulating base film, a photoresist layer that is conductive and has an etching resist function is formed on the entire surface, and then photofabrication is performed. The photoresist layer is made into a photoresist pattern layer exhibiting a predetermined shape using a technology, and then the metal thin film layer is etched using the photoresist pattern layer as an etching resist, whereby the metal exhibits a shape that matches the photoresist pattern layer. A thin film pattern layer is formed, a laminate of the metal thin film pattern layer and the photoresist pattern layer is formed into a conductive circuit pattern section, and then an anisotropic pattern is formed on the surface on which the conductive circuit pattern section is formed. A method for producing a film-like connector, comprising forming a conductive hot-melt adhesive layer. (9) The method for manufacturing a film-like connector according to claim 8, wherein the insulating base film is a surface-treated plastic film. (10) Manufacture of a film-like connector according to claim 8 or 9, wherein the conductive metal thin film pattern layer is formed using a metal or a metal oxide. Method. (11) The metal thin film pattern layer having conductivity is formed as two or more layers of different metal materials, according to any one of claims 8 to 10. A method for manufacturing a film connector. (12) A photoresist pattern layer having conductivity,
12. A method for manufacturing a film connector according to any one of claims 8 to 11, characterized in that the film connector is formed using a photopolymer to which conductive powder is added. (13) A photoresist pattern layer having conductivity,
12. The method of manufacturing a film connector according to claim 8, wherein the film connector is formed using a photopolymer that itself has conductivity. (14) Claims 8 to 8, characterized in that the hot-melt adhesive layer having anisotropic conductivity is formed using a hot-melt adhesive containing conductive powder. 14. The method for manufacturing a film connector according to any one of Item 13.