JPH0355875B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a card incorporating an integrated circuit such as an IC or an LSI (hereinafter simply referred to as an IC or an IC).

In recent years, Japanese Unexamined Patent Publication No. 18433/1983, or
As seen in Publication No. -83132, a card with a built-in IC, etc. has been proposed, and is attracting attention because its memory capacity is much larger than that of the currently widely used magnetic cards.

However, in cards that incorporate such ICs, it is necessary to protect the IC part (the IC chip, the printed circuit board on which the IC chip is mounted, and other materials from external forces, static electricity, or harmful environmental conditions). It is necessary to prevent the irregularities on the surface of the card (including containers, etc.) from appearing as irregularities on the card surface. This is because there is no standard yet for cards with built-in ICs, etc., but if we take the case of the magnetic card mentioned above as an example,
Other than the embossed characters, the allowed unevenness on the card surface is less than 50 μm, and the cards that are actually in circulation have surface unevenness of less than 1 μm, which is almost mirror-like, and cards with built-in ICs have a similar value. This is because it is desired.

For example, the thickness of the copper foil on the printed circuit board is around 35 μm, so if the IC part is encapsulated in the card as it is, considerable unevenness will occur on the card surface.
This cannot be said to be a favorable situation.

Furthermore, when forming an image at a position where an IC portion exists, it is difficult to obtain a good image if the IC portion is uneven. That is, as shown in cross section in FIG.
has an uneven shape 22 on its surface, so if the oversheet 2 is adhered as is through the adhesive layer 3, the printing layer (image forming layer) 4 formed on the back side of the oversheet 2 will be uneven on the IC part. The image will be divided due to the unevenness, and the image will be destroyed.

Conventionally, as a means to eliminate such unevenness of the IC portion, it has been proposed to fill the recesses with resin or the like to flatten the surface of the IC portion in advance.

However, with such means, it is extremely difficult to accurately apply resin to a dimensionally very small IC portion and fill the recesses, and the work is also extremely troublesome.

Therefore, the object of the present invention is to provide a card incorporating an IC, etc., which does not have the effect of unevenness on the surface of the IC, etc. enclosed in the card without having to be flattened in advance. Our goal is to provide the following.

The present invention, which was made to achieve such an object, consists of disposing a thermoplastic synthetic resin sheet as an uneven absorbing layer on the surface of a center core that holds an IC, etc. via an adhesive, and heating the thermoplastic synthetic resin sheet. This is a method of manufacturing a card incorporating an IC, etc., in which the uneven shape of the surface of the IC, etc. is absorbed into the thermoplastic synthetic resin sheet by softening it and adhering it by pressing it to the surface of the center core.

Hereinafter, the present invention will be explained in detail with reference to embodiments of the drawings.

FIG. 2 is a cross-sectional explanatory diagram of a card containing an IC manufactured by the method of the present invention. In this figure, the unevenness of the IC portion is depicted as existing only on one side, but it is natural that the unevenness is present on both sides. It is also applicable to those where

The IC 21 is held in a center core 11 made of thermoplastic synthetic resin, for example, hard vinyl chloride. I C
Reference numeral 21 is composed of an IC main body, a printed circuit board to which the IC main body is attached, accessories, etc., and may also be an LSI or other integrated circuit instead of an IC.

The IC 21 can have a thickness of 0.86 mm, for example, and a wiring pattern 23 made of copper foil is usually formed on its surface. The height of this wiring pattern 23 is 35 μm in one example, and this forms one of the factors for the surface unevenness 22 of the IC 21. In addition,
It is preferable that the thickness of the center core 11 is set to be the same as the thickness of the IC 21.

A thermoplastic synthetic resin sheet 15 is superimposed on the center core 11 holding such an IC 21 via an adhesive layer 16. This thermoplastic synthetic resin sheet 15 has an uneven shape 22 on the surface of the IC 21.
For example, hard vinyl chloride can be used. As the adhesive 16, it is preferable to use heat-reactivated salt-vinyl acetate-based resin, heat-reactivated acrylic vinyl-based resin, etc., and before laminating the thermoplastic synthetic resin sheets 15, the thermoplastic synthetic resin sheets 15 and the center core. It is preferable to apply it to each of the 11 opposing surfaces.

From this state, thermoplastic synthetic resin sheet 1
5 is heated and pressed onto the center core 11.
The heated thermoplastic synthetic resin sheet 15 is softened, so that by pressing the sheet 15 against the center core 11, as shown in FIG.
The unevenness 22 on the surface of the IC 21 is absorbed by the thermoplastic synthetic resin sheet 15, and at the same time, the thermoplastic synthetic resin sheet 15, the center core 11, and the IC 21 are bonded together by the adhesive 16.

To describe an example in which a hard vinyl chloride sheet is used as the thermoplastic synthetic resin sheet 15, in order to soften the hard vinyl chloride sheet, 60 to 120
It can be heated to a value in the range of ℃, and the pressing force on the center core 11 will not destroy the IC 21.
Although it is determined under contradictory conditions that can sufficiently absorb the unevenness 22 on the surface of the IC 21, it is preferably set within the range of 10 to 25 kg/cm ² .

Furthermore, since the IC 21 is sensitive to heat, the heating and pressurizing time is limited by its heat capacity. Therefore,
Considering this relationship, the heating and pressurizing time is preferably 5 to 10 minutes.

In this way, the uneven shape 21 on the surface of the IC 21 is
The card with the absorbed ions is further bonded to a thermoplastic synthetic resin sheet 15 with an oversheet 12 on which an image 14 is formed on the back side by printing or the like via an adhesive 13, thereby forming a card with a built-in IC, etc. can be manufactured.

Note that the adhesive 13 may be the adhesive 16 described above.
The oversheet 12 can be made of, for example, transparent hard vinyl chloride.

Although the oversheet may be provided after the irregularities have been absorbed as described above, the oversheet 21 and the thermoplastic synthetic resin sheet 15 may be laminated in advance and then heated and pressed together. IC2
The thermoplastic synthetic resin sheet 15 can also absorb the unevenness of the thermoplastic synthetic resin sheet 15.

The present invention is as described above, and since the uneven shape on the surface of an IC or the like is absorbed during the manufacturing process of the card, the uneven shape can be flattened more easily than the conventional one. It is possible to prevent unevenness from occurring on the card surface due to the uneven shape of the surface of an IC, etc., and the image that is often formed on the back side of the oversheet can also be removed by using the thermoplastic synthetic resin sheet that is the unevenness absorbing layer. Since the surface is flat, there is no risk of it being destroyed.

〔Example〕

A 0.86 mm thick white hard vinyl chloride is used for the center core, and the 0.86 mm thick IC is held in this center core. A copper foil wiring pattern with a height of 35 μm is formed on the surface of this IC. D-Tight, a heat-reactivated vinyl chloride acetate-based resin manufactured by Dainippon Ink Mfg. Co., Ltd., is used for the center core and the uneven absorption layer made of 0.1 mm thick transparent hard vinyl chloride.
HAX-1500SK, or heat-reactivated acrylic vinyl resin manufactured by Toyo Morton Co., Ltd.
ADCOTE35KL was applied and these were laminated.

Lamination conditions are flat press at 80℃.
The mixture was heated and pressurized for 7 minutes at a pressure of 20 kg/cm ² .

As a result, the unevenness on the surface of the IC was completely absorbed by the transparent hard vinyl chloride, and the surface was flat without any unevenness caused by the unevenness on the surface of the IC.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional illustration of a conventional card, and FIG. 2 is a cross-sectional illustration of a card manufactured by the method of the present invention. 11... Senko core, 12... Oversheet, 13... Adhesive, 14... Image forming layer, 15
...Thermoplastic synthetic resin sheet, 16...Adhesive,
21...IC, 22...Uneven shape.

Claims (1)

[Claims] 1. In a method for manufacturing a card comprising an oversheet and a center core holding an IC, etc., the surface of the center core holding an IC etc. has an uneven shape made of a wiring pattern on the surface. A thermoplastic synthetic resin sheet is laminated as an intermediate layer using an adhesive, and this thermoplastic synthetic resin sheet is sufficiently thicker than the height of the uneven shape, and the thermoplastic synthetic resin sheet is heated and pressed to form the surface of the IC, etc. A method for manufacturing a card incorporating an IC, etc., which absorbs the uneven shape of the IC and is bonded to the IC, etc. and a center core. 2. A method for manufacturing a card incorporating an IC or the like according to claim 1, characterized in that an oversheet is integrally laminated on the thermoplastic synthetic resin sheet and then heated and pressed. 3. The method for manufacturing a card incorporating an IC or the like according to claim 1, further comprising laminating an oversheet after heating and pressing the thermoplastic synthetic resin sheet.