JPH11175682A - Ic card and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an IC card low in cost and excellent in appearance, durability and handleability and to provide a method for manufacturing this kind of IC card with high efficiency. SOLUTION: A bear chip 2 is mounted by flip-chip method on a circuit board 1 in which a required circuit pattern 1 is formed on an insulating substrate 1a. A spacer 5 consisting of hot-melt adhesive is laminated on a surface on which the bear chip is mounted of the circuit board 1. Next, an exterior sheet 4 provided with an adhesive layer 6 consisting of the hot-melt adhesive is laminated on one surface from above the spacer 5 and the circuit board 1 is integrally thermo-compressed with the exterior sheet 4 with the spacer 5 and the adhesive layer 6. After thermo-compression, the spacer 5 is integrated with the adhesive layer 6 to form one-layered adhesive layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC card and a method for manufacturing the same, and more particularly, to a bonding structure and a bonding method for a circuit board and an exterior sheet constituting an IC card.

[0002]

2. Description of the Related Art The use of IC cards as substitutes for commuter passes, driver's licenses, telephone cards, cash cards, and the like is being studied. Since a large amount of use is expected, the structure and manufacturing process are simplified. It is one of the most important technical issues how to reduce the unit price. Also,
Since the IC card is handled by a finger and is subjected to design printing on the surface, it is particularly required that the surface has no unnecessary unevenness in order to improve the aesthetic appearance and the feeling of use.

Conventionally, as this kind of IC card,
2. Description of the Related Art A circuit board on which an IC chip is mounted and an exterior sheet bonded to an IC chip mounting surface of the circuit board are known.

As a method of manufacturing such an IC card, an IC chip is mounted on a circuit board having a required circuit pattern formed on a flat insulating substrate, and the IC chip is mounted on the IC chip mounting surface of the circuit board. A spacer having a through hole for chip insertion is bonded thereto, and thereafter, an exterior sheet having an adhesive layer provided on one side from above the spacer is bonded to form an adhesive layer in the through hole. A method of filling a part of the adhesive is known.

As another manufacturing method, a required circuit pattern is formed on a surface of an insulating substrate having a concave portion for setting an IC chip formed on one surface.
After mounting the C chip, a method of bonding an exterior sheet having an adhesive layer on one surface to a concave portion forming surface of the circuit board and filling the concave portion with a part of the adhesive constituting the adhesive layer is used. Is also known.

[0006]

According to the above-mentioned manufacturing method, an exterior card is adhered to a spacer having a flat surface or a surface of a circuit board, so that it is possible to manufacture an IC card which is generally flat and excellent in appearance and usability. It is possible to manufacture IC cards of various thicknesses by adjusting the thickness of the spacer or the thickness of the circuit board. However, in the through holes formed in the spacer or in the recess formed in the circuit board. Is filled with a part of the adhesive constituting the adhesive layer, so that an interface between the adhesive or the spacer or the circuit board is formed around the IC chip mounting portion, and when an excessive external force is applied to the IC card, the There is a problem that wrinkles easily occur at the interface.

Further, in each of the above manufacturing methods, since a spacer having a through hole or an insulating substrate having a concave portion is an indispensable component, there is a problem that the manufacturing cost is high. In particular, since the method of using the spacer requires a step of positioning and bonding the spacer to the circuit board with high precision, the manufacturing process is complicated and the manufacturing cost tends to be particularly high.

The present invention has been made in order to solve the disadvantages of the prior art, and it is an object of the present invention to provide an inexpensive and excellent aesthetic, durable, and comfortable to use.
An object of the present invention is to provide a C card and a method of manufacturing this type of IC card with high efficiency.

[0009]

According to the present invention, in order to achieve the above-mentioned object, for an IC card, an exterior sheet is bonded via an adhesive layer to an IC chip mounting surface of a circuit board on which an IC chip is mounted. In this IC card, the circuit board and the exterior sheet are formed of a flat sheet-like member, and the circuit board and the exterior sheet are bonded through a single adhesive layer made of a hot melt adhesive.

As described above, when the circuit board and the exterior sheet are formed of a flat sheet-like member, the processing for forming the through holes or the concave portions becomes unnecessary, so that the manufacturing cost of the IC card can be reduced. In addition, when the circuit board and the exterior sheet are bonded via a single adhesive layer made of a hot melt adhesive, an excessive external force is applied to the IC card because an interface between different members is not formed around the IC chip mounting portion. Wrinkles do not occur in certain parts even if
The durability of the IC card can be improved.

On the other hand, regarding the method of manufacturing an IC card,
A method for manufacturing an IC card, comprising the steps of: mounting an IC chip on a circuit board, and then bonding an exterior sheet to an IC chip mounting surface of the circuit board via an adhesive layer, wherein the IC card is mounted on the circuit board. Then, after laminating a spacer made of a hot melt adhesive formed in a sheet shape and having a through hole for accommodating the IC chip in a portion corresponding to the mounting portion of the IC chip, the outer package is placed from above the spacer. The sheets were stacked, and the circuit board, the spacer, and the exterior sheet were thermocompression-bonded.

As described above, when a circuit board and an exterior sheet are bonded using a spacer made of a hot melt adhesive, unlike a case where a spacer having no adhesive property is interposed, a spacer for bonding the spacer to the circuit board is used. Since the process can be omitted, the manufacturing cost of the IC card as a product can be reduced. In addition, the spacer made of a hot melt adhesive is softened by heating and expands and contracts flexibly, so that the thickness can be easily adjusted as compared with the case where a spacer having no elasticity is used, and the surface has a predetermined flat surface. Can be manufactured with high efficiency.

The exterior sheet can be bonded using a spacer made of a hot melt adhesive.
Bonding can also be performed using an adhesive layer made of the same or different hot melt adhesive as the hot melt adhesive constituting the spacer provided on one surface of the exterior sheet. Further, as the spacer made of the hot melt adhesive, a spacer having an appropriate thickness can be used as necessary, but in order to further improve the flatness of the product IC card, the spacer before the thermocompression bonding is used. It is particularly preferable to use one having a thickness greater than the height from the surface of the circuit board to the upper surface of the IC chip.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of an IC card according to the present invention will be described below with reference to FIGS. FIG. 1 is a sectional view of a main part of an IC card according to the present embodiment, and FIG.

As shown in FIG. 1, the IC card of this embodiment is
A circuit board 1 in which a required circuit pattern 1b is formed on one side of an insulating substrate 1a; an IC chip 2 electrically connected to a predetermined position of the circuit pattern 1b;
And an exterior sheet 4 bonded to the IC chip mounting surface via an adhesive layer 3.

The insulating substrate 1a is made of an insulating material such as glass epoxy, ceramics, polyimide resin, or polyethylene terephthalate (PET).
It is formed into a flat sheet.

As the IC chip 2, a product I
To reduce the thickness of the C card, a bare chip having no resin mold is used. A bump 2a is provided on a terminal portion of the IC chip 2 as necessary.

As the adhesive constituting the adhesive layer, for example, a hot melt adhesive such as ethylene vinyl alcohol (EVA), styrene butadiene elastomer (SBR) or polyester is used.

The exterior sheet 4 can be formed using any plastic sheet, but is excellent in heat resistance and chemical resistance, and does not generate harmful gas such as chlorine gas when incinerated, and is excellent in environmental properties. For this reason, it is particularly preferable to use a plastic sheet such as PET, PEN (polyethylene naphthalate), or PES (polyether sulfone). As the exterior sheet 4, a flat sheet having no depression or the like on the surface is used.

Next, a method of manufacturing the IC card according to the embodiment will be described. As shown in FIG. 2, a required circuit pattern 1b is formed on one surface of the insulating substrate 1a,
In addition, a circuit board 1 on which an IC chip 2 is mounted at a predetermined position of the circuit pattern 1b and a hot melt adhesive are formed into a sheet, and the IC chip is stored in a portion corresponding to a mounting portion of the IC chip 2. 5 provided with a through hole 5a for the opening, and an exterior sheet 4 on one side of which an adhesive layer 6 made of the same kind of hot melt adhesive as the hot melt adhesive constituting the spacer 5 is formed.

Next, the spacer 5 is positioned and mounted on the IC chip mounting surface of the circuit board 1, and the IC 5 is inserted into the through hole 5a.
The chip 2 is stored. Further, the exterior sheet 4 is overlaid on the spacer 5 with the adhesive layer 6 facing downward. Finally, a pressing force is applied to the circuit board 1, the spacer 5, and the exterior sheet 4 while being heated, and the circuit board 1 and the spacer 5 are thermocompression-bonded, and the spacer 5 and the adhesive layer 6 are thermocompression-bonded. . As a result, the hot melt adhesive constituting the spacer 5 and the hot melt adhesive constituting the adhesive layer 6 are integrated, and the adhesive layer 3 shown in FIG. 1 is formed.

Hereinafter, more specific examples and comparative examples of the IC card according to the present invention will be shown to clarify the effects of the present invention.

<First Embodiment> PET having a thickness of 100 μm
The circuit board 1 in which the circuit pattern 1b is formed by etching on the insulating substrate 1a made of a film has a thickness of 100
A bare chip 2 having a gold bump formed on a terminal part in μm
Flip chip mounting was performed via the anisotropic conductive film 7. The thickness of the joint was about 25 μm. The spacer 1 has a thickness of 1 on the bare chip mounting surface of the circuit board 1.
A 40 μm EVA sheet was laminated. Accordingly, at this time, the surface of the EVA sheet 5 is at a position about 15 μm higher than the upper surface of the bare chip 2 as shown in FIG. Next, from the top of the EVA sheet 5, one side has a thickness of 50 μm.
m on the exterior sheet 4 on which the EVA adhesive layer 6 is formed,
The VA adhesive layer 6 was laminated toward the EVA sheet 5 side, and these members were integrally thermocompression-bonded. As the exterior sheet 4, a PET film having a thickness of 100 μm was used, and the heating temperature was 130 ° C. at the maximum, and 100 ° C. during pressure bonding. Finally, the thermocompression-bonded body thus manufactured was cut into a predetermined shape to form an IC card having a cross-sectional structure shown in FIG.

<Second Embodiment> As the spacer 5, SBR
Sheets were used. Others are the same as the IC card according to the first embodiment.

Third Embodiment A silver paste was used as a bonding material for the bare chip 2. Others are the same as the IC card according to the first embodiment.

<Fourth Embodiment> As a method for forming the circuit pattern 1b, a printing method using a silver paste was used. Others are the same as the IC card according to the first embodiment.

Fifth Embodiment As the spacer 5, an EVA sheet having a thickness of 125 μm before thermocompression bonding was used. Therefore, in the present embodiment, when the EVA sheet is laminated on the bare chip mounting surface of the circuit board 1, the surface of the EVA sheet 5 is almost the same height as the upper surface of the bare chip 2, as shown in FIG. become. Others are the same as the IC card according to the first embodiment. As shown in FIG. 4, the IC card manufactured by this method also has the same cross-sectional structure as the IC card according to the first to fourth embodiments.

<Comparative Example> A 120 μm thick PET film having no thermocompression bonding property was used as a spacer.
The spacer 11 was bonded to the bare chip mounting surface of the circuit board 1 via an adhesive layer 12 having a thickness of 5 μm as shown in FIG. Next, on the spacer 11, a thickness of 50 is formed on one side.
The exterior sheet 4 on which the μm EVA adhesive layer 6 was formed was thermocompression-bonded. Other conditions were the same as those of the IC card according to the first embodiment. The IC card of this example is shown in FIG.
The sectional structure shown in FIG.

The IC card according to the first to fifth embodiments does not require a spacer to be attached to the circuit board 1 as compared with the IC card according to the comparative example, so that the manufacturing process is simplified.
It could be manufactured at low cost. Further, the IC cards according to the first to fourth embodiments in which the surface height of the spacer 5 made of the hot melt adhesive is higher than the upper surface height of the bare chip 2 have a high surface flatness, good aesthetic appearance and usability. And was obtained. On the other hand, in the IC card according to the fifth embodiment in which the surface height of the spacer 5 is substantially the same as the upper surface height of the bare chip 2, as shown in FIG. Was at a level that would not hinder practical use. On the other hand, the IC card according to the comparative example manufactured by the conventional technique had a large step around the bare chip setting portion as shown in FIG. 6 and was not suitable for practical use.

In addition, in the IC cards according to the first to fifth embodiments, since the periphery of the IC chip mounting portion is surrounded by a uniform hot melt adhesive, a large bending stress is applied to the IC card. In addition, deformations such as wrinkles around the IC chip mounting portion were unlikely to occur. On the other hand, in the IC card according to the comparative example, deformation such as wrinkles easily occurred at the interface between the adhesive layer 6 and the spacer 11 around the IC chip mounting portion or between the circuit board 1 and the adhesive layer 6.

Therefore, according to the first to fifth embodiments,
It was confirmed that a thin IC card having excellent aesthetics, durability, and usability can be obtained at low cost.

In the above embodiment, the exterior sheet 4 having the adhesive layer 6 formed on one side is laminated on the spacer 5 formed by hot melt adhesive, but the thickness of the spacer 5 is adjusted. Thereby, the exterior sheet 4 on which the adhesive layer 6 is not formed can be laminated on the spacer 5.

[0033]

As described above, in the IC card according to the present invention, since the circuit board and the exterior sheet are formed of flat sheet members, the IC card is inexpensive as compared with the case of forming through holes or recesses in these. Can be manufactured. In addition, since the circuit board and the exterior sheet are bonded via a single adhesive layer made of a hot melt adhesive, no interface between different members is formed around the IC chip mounting portion, thereby improving durability against bending. Can be.

On the other hand, in the IC card manufacturing method of the present invention, since the circuit board and the outer sheet are bonded using the spacer made of hot melt adhesive, unlike the case where the spacer having no adhesive property is interposed, the spacer is used. Process for bonding the IC to the circuit board can be omitted, and the product IC
The manufacturing cost of the card can be reduced. In addition, the spacer made of a hot melt adhesive is softened by heating and expands and contracts flexibly, so that the thickness can be easily adjusted as compared with the case where a spacer having no elasticity is used, and the surface has a predetermined flat surface. Can be manufactured with high efficiency.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an IC card according to an embodiment.

FIG. 2 is an explanatory diagram of a method of manufacturing an IC card according to an embodiment.

FIG. 3 is an illustration of a method of manufacturing an IC card according to a fifth embodiment.

FIG. 4 is a sectional view of a main part of an IC card according to a fifth embodiment.

FIG. 5 is an explanatory diagram of a method of manufacturing an IC card according to a comparative example.

FIG. 6 is a sectional view of a main part of an IC card according to a comparative example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Circuit board 1a Insulating board 1b Circuit pattern 2 IC chip (bare chip) 2a Bump 3 Adhesive layer 4 Exterior sheet 5 Spacer 5a Through hole 6 Adhesive layer 11 Spacer 12 Adhesive layer

Claims (4)

[Claims] 1. An IC on a circuit board on which an IC chip is mounted.
In an IC card in which an exterior sheet is bonded to a chip mounting surface via an adhesive layer, the circuit board and the exterior sheet are formed of flat sheet members, and the circuit board and the exterior sheet are made of a hot melt adhesive. An IC card which is adhered via a layer adhesive layer. 2. After mounting an IC chip on a circuit board,
In a method of manufacturing an IC card, the method includes a step of bonding an exterior sheet to an IC chip mounting surface of the circuit board via an adhesive layer, wherein a hot melt adhesive formed in a sheet shape is formed on the circuit board on which the IC chip is mounted. After a spacer having a through hole for accommodating the IC chip is laminated on a portion corresponding to the mounting portion of the IC chip, the package sheet is laminated from above the spacer, and the circuit board and the spacer are laminated. A method for producing an IC card, comprising thermocompression bonding an outer sheet and an outer sheet. 3. The method for manufacturing an IC card according to claim 2, wherein the exterior sheet is made of a hot-melt adhesive of the same type or different from the hot-melt adhesive constituting the spacer on the adhesive surface with the spacer. A method for manufacturing an IC card, comprising using an IC card provided with an adhesive layer. 4. The method for manufacturing an IC card according to claim 2, wherein a thickness of the spacer before thermocompression bonding is larger than a height from a surface of the circuit board to an upper surface of the IC chip. A method for producing an IC card.