JPH04171886A - Manufacture of electronic part having metallic foil circuit pattern and composite supporter having metallic foil circuit pattern used therein - Google Patents

Abstract

PURPOSE:To easily transfer a thin metallic foil circuit pattern to an electronic part by sticking the electronic part to the surface of the metallic foil circuit pattern formed on the surface of a photosensitive adhesive layer with a composite supporter, which consists of a light transmitting supporter and the photosensitive adhesive layer, applying light to decrease the adhesiveness of the photosensitive adhesive layer, and peeling the composite supporter off the metallic foil circuit pattern. CONSTITUTION:A copper foil circuit pattern 1a is formed on the surface of a photosensitive adhesive film 5 with the photosensitive adhesive film 5 as a composite supporter consisting of a light transmitting supporter 3 and photosensitive adhesive 4 formed on one face thereof. Liquid bond 6 is applied to the surface of the copper foil circuit pattern 1a and the copper foil circuit pattern 1a is pressingly applied to a ferrite head 7. The bond 6 is hardened and ultraviolet rays are applied to the photosensitive adhesive film 5 from the light transmitting supporter 3 to harden the photosensitive adhesive 4 and decrease its adhesiveness. Thereby the photosensitive adhesive film 5 can be easily peeled off the copper foil circuit pattern 1a and a coil circuit on which only the attached copper foil circuit pattern 1a is left is made.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing electronic components with a metal foil circuit pattern, in which only the metal foil circuit pattern is transferred to an electronic component, and a composite support with a metal foil circuit pattern used therein. It is something.

[Conventional technology]

Electronic devices are becoming smaller and thinner year by year.
In order to satisfy such demands, flexible circuit boards are often used as electronic circuits used in electronic devices. The above-mentioned flexible circuit board is usually constructed by pasting insulating films on both sides of a circuit pattern made of copper foil via an adhesive. From the perspective of making such flexible circuit boards thinner, it is desirable to make the thickness of the insulating film and adhesive layer as thin as possible, and the thinnest ( can be ideal.However,
Among the circuit patterns of the flexible circuit board, there are circuit patterns that are not connected to each other. Therefore, when constructing a circuit pattern from only copper foil as described above, each part of the circuit pattern is etched without etching the copper foil attached to the board. The parts become disjointed, making it difficult to maintain accurate positional relationships among the parts. Also,
It may be possible to connect the parts that make up the circuit pattern and then cut them as needed after etching, but when they are cut, the mutual positional relationship between the parts that make up the circuit pattern will be disrupted, making it difficult to maintain the proper state. It becomes difficult to maintain the voltage, and problems such as short circuits occur. Furthermore, there has been conventionally known a method of directly etching or chemically milling relatively thick metal foil to produce shadow masks for cathode ray tubes and blades for electric razors.

However, the metal foil used for flexible circuit boards is
Since the thickness is thin and the strength of the metal foil is weak, the above method cannot be applied.

On the other hand, when etching a copper foil and adhesive film bonded together, the commonly used adhesives have poor chemical resistance to etching solutions, and the etching solution penetrates between the adhesive and the copper foil, causing the copper The problem arises that the surface of the foil is eroded. Furthermore, since such adhesives have too strong adhesive force, there is a problem in that when the circuit patterns are peeled off from the adhesive film, the positional relationship between the circuit patterns becomes distorted.

[Problems to be Solved by the Invention] As described above, with the conventional methods, it is difficult to transfer only a circuit pattern onto an electronic component to reduce its thickness.

The present invention was made in view of the above circumstances, and aims to provide a method for easily transferring a thin metal foil circuit pattern to an electronic component, and a composite support with a metal foil circuit pattern used therein. .

[Means to solve the problem]

In order to achieve the above object, the present invention uses a composite support in which a photosensitive adhesive layer is formed on one side of a light-transmitting support, and a metal foil circuit is formed on the surface of the photosensitive adhesive layer of this composite support. After forming a pattern and pasting electronic components on the metal foil circuit pattern surface via an adhesive layer, light is irradiated from the light-transmissive support side to harden the photosensitive adhesive layer to make it sticky. The first gist is a method for manufacturing an electronic component with a metal foil circuit pattern, in which the light-transparent support is peeled together with the photosensitive adhesive layer from the metal foil circuit pattern surface in that state, and the light-transparent support is peeled from the metal foil circuit pattern surface. The second gist is a composite support with a metal foil circuit pattern, in which a metal foil circuit pattern is formed on the surface of the photosensitive adhesive layer of the composite support, which has a photosensitive adhesive layer formed on one side of the composite support.

[Function] That is, the present invention uses a composite support consisting of a light-transmitting support and a photosensitive adhesive layer, and forms a metal foil circuit pattern on the surface of the photosensitive adhesive layer.

After adhering the electronic component to the surface of the metal foil circuit pattern, the composite support is peeled off from the metal foil circuit pattern by irradiating it with light to reduce the tackiness of the photosensitive adhesive layer. Therefore, only the metal foil circuit pattern is transferred onto the electronic component.

Next, the present invention will be explained in detail.

The composite support with a metal foil circuit pattern of the present invention uses a composite support in which a photosensitive adhesive layer is formed on one side of a light-transmitting support, and a metal foil circuit pattern is formed on the surface of this photosensitive adhesive layer. Obtained by forming.

Examples of the light-transmitting support include polyethylene terephthalate, polyvinyl chloride, and polyethylene.

Examples include polypropylene. The thickness of such a light-transmitting support is usually preferably set to 15 to 50 μm.

The above-mentioned photosensitive adhesive layer is made of a conventionally known rubber-based or acrylic-based pressure-sensitive adhesive with a low molecular weight compound having at least two photopolymerizable carbon-carbon double bonds in the molecule (hereinafter referred to as "photopolymerizable"). It is formed using a photosensitive adhesive composition containing a photopolymerization initiator and a photopolymerization initiator.

The above-mentioned pressure-sensitive adhesive uses a rubber-based polymer such as natural rubber or various synthetic rubbers, or an acrylic polymer such as polyacrylic acid alkyl ester or polymethacrylic acid alkyl ester as a base polymer, and if necessary, polyester is used as the base polymer. Examples include those containing crosslinking agents such as isocyanate compounds and alkyl etherified melamine compounds.

The photopolymerizable compound has a molecular weight of 1oooo
The following are preferred, and more preferably have a molecular weight of 5,000 or less and have a photopolymerizable carbon-carbon double bond in the molecule so that the photosensitive adhesive layer can be efficiently formed into a three-dimensional network by light irradiation. Those having 2 to 6 are used.

Specifically, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, etc. may be used alone or in combination. It is used as The amount of the photopolymerizable compound to be used is preferably set in the range of 1 to 100 parts per 100 parts by weight (hereinafter abbreviated as "parts") of the pressure-sensitive adhesive.

Examples of the photopolymerization initiator include isopropyl benzoin ether, isobutyl benzoin ether, benzophenone, and Michler's ketone.

Examples include chlorothioxanthone, dodecylthioxanthone, dimethylthioxanthone, diethylthioxanthone, acetophenone diethyl ketal, benzyl dimethyl ketal, and α-hydroxymethylphenylpropane, which may be used alone or in combination. The amount of such a photopolymerization initiator used is preferably set in the range of 0.1 to 5 parts based on 100 parts of the pressure-sensitive adhesive.

The photosensitive adhesive composition forming the photosensitive adhesive layer is
It is obtained by mixing each of the above components.

The composite support is produced, for example, by applying the photosensitive adhesive composition on the surface of a light-transmitting support to form a photosensitive adhesive layer, and heating as required.

The thickness of the photosensitive adhesive layer thus formed is preferably set in a range of 5 to 25 μm.

A metal foil circuit pattern is formed on the surface of the photosensitive adhesive side of the composite support thus obtained.

The metal foil is not particularly limited, and may include various conventionally known metal foils, but copper foil is usually used.

To describe in more detail the method for manufacturing the metal foil circuit patterned composite support of the present invention, the composite support is manufactured, for example, as follows. That is, first, as shown in FIG. 1, a photoresist layer 2 is formed on one side of the metal M1. Next, as shown in FIG. 2, a composite support 5 in which a photosensitive adhesive layer 4 is formed on one side of a light-transmitting support 3 is attached to the other side of the metal foil 1. Then, by exposing and developing, the photoresist layer 2 is formed into a circuit pattern. Then, the exposed portion of the metal foil 1 is etched and the photoresist layer 2 is peeled off. Through these series of steps, as shown in FIG. 4, a composite support with a metal foil circuit pattern on which a metal foil circuit pattern 1a is formed is produced.

The present invention will now be described in detail based on examples.

〔Example〕

1 to 7 show the manufacturing process of a coil circuit according to an embodiment of the electronic component with a copper foil circuit pattern of the present invention. That is, first, as shown in FIG. 1, a photoresist layer 2 is formed by coating one side of a copper foil 1 with a photosensitive liquid photoresist. Next, as shown in FIG. 2, on the other side of the copper foil 1, a photosensitive adhesive film 5 (for example, Nitto UE-30H (manufactured by Denkosha) is pasted using a roll laminator. The laminating temperature at this time is 60~
It is preferable to set the lamination speed at 80° C. to 0.5 to 1 m/min. Then, a photomask (not shown) on which a circuit pattern to be formed is formed is brought into close contact with the surface of the photoresist layer 20. and expose. After exposure, a development process is performed using an appropriate developer to form the photoresist layer 2 into a circuit pattern as shown in FIG. Next, the exposed portion of the copper foil 1 is etched using an acidic etching solution commonly used for processing printed circuit boards, such as ferric chloride solution or cupric chloride solution. Subsequently, the photoresist layer 2 is peeled off using a stripping solution. As the stripping liquid, an alkaline solution is usually used, but since the photosensitive adhesive 4 of the photosensitive adhesive film 5 has low alkali resistance, an organic solvent such as acetone or methyl ethyl ketone is used. Through these series of steps, the fourth
As shown in the figure, a copper foil circuit pattern la is formed on the surface of the photosensitive adhesive film 5. Then, as shown in FIG. 5, a liquid adhesive 6 such as epoxy for fixing electronic components is applied to the surface of the copper foil circuit pattern la by screen printing or the like, and through this adhesive 6, as shown in FIG. The copper foil circuit pattern Ia is crimped onto the ferrite head 7 as shown in FIG. During this pressure bonding, the adhesive 6 is pressed and spreads evenly over the surface of the copper foil circuit pattern 1a as shown in the figure.Next, after the adhesive 6 is cured, it is applied to the photosensitive adhesive film 5.
Ultraviolet rays are irradiated from the side of the light-transmitting support 3 to harden the photosensitive adhesive 4 and reduce its tackiness. In this case, the adhesive force of the photosensitive adhesive 4 is preferably reduced from an initial adhesive force of 1000 g/cm to 150 g/cm. Because this ultraviolet irradiation reduces the adhesiveness of the photosensitive adhesive 4 to the copper foil circuit pattern Ia,
The photosensitive adhesive film 5 can be easily peeled off from the copper foil circuit pattern 1a, and as shown in FIG. 7, a coil circuit with only the copper foil circuit pattern 1a remaining and attached is manufactured.

The ultraviolet light irradiated to the photosensitive adhesive film 5 is as follows:
It is preferable that the wavelength is 365 na+ and the energy is 460 a+J/d.

Furthermore, when attaching the copper foil circuit pattern la to the ferrite head 7, instead of applying the adhesive 6 to the surface of the copper foil circuit pattern la as described above, the adhesive 6 is applied to the surface side of the ferrite head 7. You can. Furthermore, the adhesive 6
is not limited to a liquid form, and a film form may also be used.

Note that the above-mentioned coil circuit can be manufactured continuously by, for example, a tape carrier method.

That is, a long tape-like base material having a width of 500 mm is prepared, in which the photosensitive adhesive film 5 is adhered to one side of the copper foil 1 and the photoresist layer 2 is formed on the other side of the copper foil 1. This long base material is slit to match the size of the final product, as shown in FIG. The width of this slit is determined to be approximately 10 to 15 mm wider than the final product size, since sprocket holes are punched out on both sides of the base material 8 in the next step. Then, so that each long base material 8 that has been slit in this way can be transferred to each step continuously, a ninth
As shown in the figure, sprocket holes 9 are punched out on both edges of the base material 8, and the base material 8a with the sprocket holes 9 punched out is set in a tape carrier device that continuously transfers the tape carrier device, and this device is operated to continuously A predetermined circuit pattern is formed on the base material 8 using an exposure device. Exposure by the continuous exposure device described above is usually performed by an indirect method.

After the exposure step, the coil circuit can be continuously manufactured by performing the same steps as the manufacturing step using the tape carrier device.

〔Effect of the invention〕

As described above, the present invention uses a composite support consisting of a light-transmitting support and a photosensitive adhesive layer, and forms a metal foil circuit pattern on the surface of the photosensitive adhesive layer. After adhering the electronic component to the surface of the metal foil circuit pattern, the composite support is peeled off from the metal foil circuit pattern by irradiating it with light to reduce the tackiness of the photosensitive adhesive layer. Therefore, only the metal foil circuit pattern can be transferred and formed on the electronic component. Therefore, it is possible to make electronic components thinner.

[Brief explanation of drawings]

FIG. 1, FIG. 2, FIG. 3, FIG. 4, FIG. 5, FIG. 6, and FIG. 7 are explanatory diagrams showing the manufacturing process of an embodiment of the present invention;
FIG. 8 and FIG. 9 are explanatory diagrams of a tape-shaped base material used when continuously carrying out the manufacturing process of the embodiment of the present invention. 1a...Copper foil circuit pattern 2...Photoresist layer 3...Light-transparent support 4...Photosensitive adhesive side
5... Photosensitive adhesive film 6... Adhesive 7...
・Ferrite head patent applicant: Nitto Denko Co., Ltd. agent, patent attorney Yukihiko Nishifuji 11piI Figure 1! ; 2 figures, 4 figures, 5 figures, 6 figures, 7 figures, 8 figures, $9, procedural amendments (voluntary) 1. Description of the case Composite support with metal foil circuit pattern using Patent Application No. 300379 of 1990 3, Representative of the person making the amendment: Goro Kamai 6, Contents of the amendment (1) Statement of claims in the specification Correct as shown in the attached sheet. 7. List of attached documents (1) Attachment (document containing the entire text of the amended claims) 1 copy [Attachment] 2. Claims (Re: Photosensitive adhesive on one side of the light-transmitting support) Using a composite support on which an adhesive layer is formed, a metal foil circuit pattern is formed on the surface of the photosensitive adhesive layer of this composite support, and electronic components are attached to the metal foil circuit pattern surface via the adhesive layer. After that,
The light-transmitting support is irradiated with light to cure the photosensitive adhesive layer and reduce its adhesiveness, and in this state, the light-transmitting support is attached to the metal foil circuit pattern together with the photosensitive adhesive layer. A method for manufacturing an electronic component with a metal foil circuit pattern, which is characterized by peeling from a surface. (2) The method for manufacturing an electronic component with a metal foil circuit pattern according to claim m, wherein the composite support is formed into a tape shape, and each of the above steps is performed sequentially and continuously as the tape moves. (3) With a metal foil circuit pattern, characterized in that a metal foil circuit pattern is formed on the surface of the photosensitive adhesive layer of a composite support in which a photosensitive adhesive layer is formed on one side of a light-transmitting support. Composite support.

Claims (3)

[Claims] (1) Using a composite support in which a photosensitive adhesive layer is formed on one side of a light-transmitting support, a metal foil circuit pattern is formed on the surface of the photosensitive adhesive layer of this composite support, and the adhesive layer is formed on the surface of the composite support. After pasting electronic components on the above metal foil circuit pattern surface through
Light is irradiated from the surface side of the light-transmitting support to cure the photosensitive adhesive layer and reduce its adhesiveness, and in this state, the light-transmitting support is attached to the metal foil circuit pattern together with the photosensitive adhesive layer. A method for manufacturing an electronic component with a metal foil circuit pattern, which is characterized by peeling from a surface. (2) Claim (2) wherein the composite support is formed into a tape shape, and each of the above steps is performed sequentially and continuously as the tape moves.
) A method for producing electronic components with metal foil circuit patterns. (3) With a metal foil circuit pattern, characterized in that a metal foil circuit pattern is formed on the surface of the photosensitive adhesive layer of a composite support in which a photosensitive adhesive layer is formed on one side of a light-transmitting support. Composite support.