JP2007012700A - Laminated sheet circuit wiring module and inner circuit connection structure of ic tag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To connect circuit patterns and elements with a simple means without flip chip connection and to simplify an IC module mounting process of a laminated sheet. <P>SOLUTION: Conductive foil is stuck to a surface of a substrate sheet formed of thermoplastic resin. A wiring module having a configuration where conductive foil passes through a hole made in the sheet and it projects to a sheet rear side is used. The wiring module is overlapped with the sheet where the circuit pattern is formed on the surface so that the hole is loaded on the circuit pattern. The wiring module is integrated with the sheet by heating press, and the circuit patterns are electrically connected through the wiring module. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In the present invention, when a signal processing circuit is provided in the inner layer of a sheet molded body formed by heating and pressing a laminated sheet, the circuit pattern and the terminals of the elements arranged in the molded body are electrically connected to each other. The present invention relates to a wiring module and an IC tag structure in which an internal circuit is connected using the wiring module.

  Recently, IC cards and IC tags (hereinafter collectively referred to as IC tags) incorporating IC modules made up of elements such as IC chips and antennas for data transmission / reception have been used in various life scenes.

These IC tags are laminated and integrated by placing an IC module on the inner layer and stacking a plurality of plastic sheets, and stacking the sheets together with an adhesive or adhesive, or by heat-sealing the sheets together. This is formed by a processing step that cuts it into a predetermined shape. Among these, the IC module to be loaded is mounted with an element such as an IC chip on a sheet on which an antenna pattern is formed by etching or printing. The IC inlet is integrated into the laminated sheet, and the IC inlet is sandwiched between the laminated sheets.
In such an IC inlet manufacturing process, solder balls and solder bumps are often used for electrical connection of each element such as an antenna and an IC chip, and the bumped IC chip is temporarily placed on the antenna. Thereafter, flip-chip connection in which the bump and the antenna are thermocompression bonded and the IC chip is directly mounted on the antenna is widely performed (see, for example, Patent Document 1).

JP 11-102926 A

When an element such as an IC chip is mounted by flip chip connection, it is necessary to use a dedicated element formed corresponding to the connection method. However, since the dedicated element is expensive, an IC inlet and this are used. There is a problem that the manufacturing cost of the IC tag is inevitably high.
Conventionally, double-sided conductor plates have been configured using solder balls or solder bumps to make the spiral antenna circuit pattern start and end points conductive, but both sides of the antenna circuit pattern are only connected to the antenna circuit. It would be uneconomical to construct a conductor plate.
If the components of the IC module can be mounted within the process of integrating the laminated sheets without using the IC inlet, the cost of the IC tag can be reduced. In fact, no simple method for electrically connecting elements has been found.

  In view of the above-described problems of the prior art, the present invention makes it possible to connect circuit patterns and elements by simple means without using flip-chip connection, and in the process of integrating laminated sheets, It is an object to be able to mount a component of a module.

  The present inventor has conducted extensive research to solve the above problems, and without using a double-sided conductor plate, a sheet having a conductive path formed on the surface is overlaid on an inner circuit pattern to connect the conductive path and the circuit pattern. Even in such a state, by stacking and integrating the sheet material and thickness, the thickness of the conductive path, etc., as appropriate, the circuit pattern can be securely connected and sufficient durability can be secured. The present invention has been completed by finding that the above solution is possible.

  That is, the present invention is a wiring module for electrically connecting internal circuit patterns of laminated sheets integrated by a hot press, and a conductive foil is formed on the surface of a base material sheet made of a thermoplastic resin. The conductive foil has a configuration in which the conductive foil protrudes to the back side of the sheet through a through hole formed in the sheet.

The wiring module configured as described above forms a through hole penetrating to the back surface of the sheet of the base sheet having the conductive foil bonded to the surface, and the edge of the through hole extends from the sheet surface side to the back surface of the sheet. By folding back to the side, the conductor foil can be projected to the back side of the sheet.
Alternatively, by forming a through hole in the base sheet, covering the through hole on the sheet surface and bonding the conductor foil together, and by immersing the conductor foil in the hole, the conductive foil is placed on the back side of the sheet. Can be protruded.

Also, the internal circuit connection structure of the IC tag of the present invention uses the wiring module having the above-described configuration, and is arranged so that the through hole is placed on the circuit pattern on the sheet having the circuit pattern formed on the surface. The circuit patterns are electrically connected to each other through the wiring module by stacking and integrating the wiring module with the sheet by a heating press.
In addition, the wiring module having the above configuration in which an IC chip is mounted on the surface of the sheet and the terminals thereof are connected to the conductive foil, and the through hole is formed on the sheet on which the circuit pattern of the antenna is formed on the surface. It is characterized in that the IC chip and the antenna are electrically connected by arranging them so as to be placed on each other and superimposing them and integrating the wiring module with the sheet by a heating press.

The wiring module of the present invention mounts an IC module as a means for easily producing an inlet sheet on which an IC module is mounted without using flip chip connection or in a process of integrating laminated sheets without using an inlet sheet. It is used as a means to do.
FIG. 1 and FIG. 3 show an embodiment of the wiring module of the present invention. The wiring module 1 has a conductive foil 12 bonded to the surface of an elongated rectangular base material sheet 11 in a strip shape, Through holes 13, 13 penetrating the front and back are formed on both sides of the base sheet 11, and the conductive foil 12 on the surface projects through the through holes 13, 13 to the back side of the sheet.
Specifically, FIG. 1 shows that by forming through holes 13 and 13 penetrating to the back surface of the sheet on the conductive foil 12 bonded to the sheet surface and folding the edges of the through holes 13 and 13 from the sheet surface side to the sheet back surface side. The conductor foil 12 is projected from the back side of the sheet. In FIG. 3, the through holes 13 and 13 are formed in the base sheet 11, and then the conductive foil 12 is bonded to the sheet surface so as to cover the through holes 13 and 13. , 13 so that the conductor foil 12 protrudes to the back side of the sheet by being immersed.

The IC tag includes an inlet sheet in which an IC module is integrated between a pair of core sheets made of a thermoplastic resin such as an amorphous polyester resin, and the core sheet is connected to the outer surface of both core sheets. It is formed by overlaying oversheets made of an integral resin composition and integrating them with a hot press. When the wiring module of the present invention is used instead of the inlet sheet, an IC module is loaded on the core sheet, the wiring module 1 is overlaid thereon, and the core sheet is overlaid on the outer surface. . Therefore, as the base material sheet 11 of the wiring module 1, a resin composition having good adhesion to the core sheet or heat fusion when being integrated by a hot press is used.
For example, as a constituent material of the base sheet 11, a thermoplastic resin sheet that is deformed by heating and pressurization, for example, a polyester resin such as PET, a polycarbonate resin, a vinyl chloride resin, a polyethylene terephthalate resin, an ABS resin, a non-resin PETG, which is a crystalline polyester resin, is suitable.

  Among the resins, PETG has high fluidity during hot pressing, and if PETG is used for all the laminated sheets of the IC tag including the base sheet 11, the entire sheet has good heat-fusibility and low-temperature fusion. Although it becomes possible, on the other hand, the frequency at which the conductor foil 12 on the base material sheet 11 is disconnected is increased. Therefore, in order to prevent the conductor foil 12 from being disconnected at the time of hot pressing within a range that does not impair the heat-fusibility of PETG used as a laminated sheet, one of the overlapping sheets sandwiching the conductor foil 12 is PETG and the other sheet is the same. Set to a material with higher heat resistance, that is, when PETG is used for the base sheet 11, use a material with high heat resistance as a core sheet or other sheet overlapping therewith, When PETG is used for the core sheet or other sheet that overlaps the sheet for use 11, it is preferable to use a material having high heat resistance as the sheet for base 11. When a heat-resistant material is used for the base sheet 11, the heat-resistant material is not exposed on the end faces of the laminated sheets and is hidden inside, so that end face peeling and poor adhesion hardly occur. As the material having high heat resistance, for example, PET, PEN, PCTG / PC alloy or the like can be used.

  The base sheet 11 can be formed in an appropriate shape that overlaps between a circuit pattern to be conducted and terminals. For example, when connecting the start point and end point of the antenna, the base sheet 11 is formed in a thin strip shape slightly longer than the distance between the start point and end point of the antenna so as to overlap only the portion between the start point and end point of the antenna. It may be provided. Alternatively, it may be formed in a wide dimensional shape large enough to cover the entire antenna, and may be provided so as to overlap with portions other than the start point and end point of the antenna. The thickness of the substrate sheet 11 is preferably about 20 μm to 100 μm.

As a constituent material of the conductor foil 12 to be bonded to the surface of the substrate sheet 11, copper, an alloy thereof, aluminum, or the like can be used. Copper is suitable because of its good extensibility during hot pressing. The thickness of the conductor foil 12 is set to a dimension that can ensure sufficient rigidity not to be disconnected even by bending stress applied at the time of hot pressing at the time of tag forming or at the time of use of the tag after forming, and is preferably about 18 μm to 35 μm. . Further, the width of the conductor foil 12 is set to a dimension that is larger than the opening diameter of the through-hole 13 described later and smaller than the width of the base sheet 11.
The conductor foil 12 can be bonded to the surface of the base sheet 11 by heat-sealing. However, as long as it is integrally fixed to the surface of the base sheet 11, other materials such as an adhesive and a pressure-sensitive adhesive are used. Any appropriate means may be used.
When the conductor foil 12 is heat-sealed to the base sheet 11 or when the antenna pattern is heat-sealed on the core sheet, the base sheet 11 or the sheet with a hot melt layer as the core sheet, For example, if a PETG sheet with a hot melt layer having a thickness of 30 μm is used, it can be fused at a low temperature, which is preferable in terms of productivity.

  The through holes 13 formed in the substrate sheet 11 correspond to the positions of the patterns to be connected and the dimensions between the terminals so that they overlap the upper surface of the patterns and terminals to be connected when the wiring module 1 is overlaid on the circuit pattern. Formed. The through holes 13 are formed according to the number of patterns and terminals to be connected, such as two when two terminals are connected and three when three terminals are connected.

  In order to project the conductor foil 12 through the through-hole 13 to the back side of the sheet, in the case of folding the edge of the through-hole 13 shown in FIG. After the foil 12 is bonded (FIG. (A)), the through holes 13 and 13 are drilled on the conductor foil 12 (FIG. (B)), and then the edge of the through hole 13 is formed by winding (curling or hemming). Can be performed by folding the sheet from the sheet surface side to the back surface side ((C) in the figure). In this case, the through-hole 13 is formed to have a size capable of inserting the winding mold, for example, a diameter of about 0.5 mm to 0.6 mm.

Further, in the case where the conductor foil 12 is immersed in the through-hole 13 shown in FIG. 3, the through-holes 13 and 13 are formed in the base sheet 11 in advance, and the conductor foil 12 is bonded to the upper surface of the conductor foil 12. This can be done by forming the portion of the foil 12 that covers the through-hole 13 in a direction that protrudes toward the back side of the sheet. In this case, the through hole 13 is formed with a diameter of about 1 mm.
As shown in FIG. 4 (A), the forming is performed in a shape that is curved in a dish shape to the extent that the end of the conductor foil 12 covering the through-hole 13 protrudes from the through-hole, as shown in FIG. 4 (B). As shown in the figure, any of the shapes that break through the end portion and protrude below the through hole 13 may be used. Forming can be performed by pressing a pressing tool having a diameter smaller than that of the through-hole 13 from above the conductor foil 12. However, when the thickness of the conductor foil 12 is thin, the forming for the substrate on which the through-hole 13 is formed. The conductive foil 12 can be bonded to the surface of the sheet 11 by thermal fusion and simultaneously with thermal deformation. For example, a soft release paper having followability, preferably a release paper made of fluororesin, is stacked on the surface side of the conductor foil 12, while a harder release paper such as PET is used on the back side of the base sheet 11. If the release paper made of is stacked and heated and pressed in that state, the soft release paper is deformed and enters the through-hole 13, and the conductor foil 12 is immersed in the through-hole 13 along with this, and the conductive foil 12 is formed to a depth at which the end is exposed on the back side of the sheet.

When the wiring module 1 uses a sheet of an appropriate size to produce a plurality of wiring modules in a batch, the configuration shown in FIG. 1 is the contour of the base sheet 11 within the sheet surface. The step of bonding the conductor foil 12 having a length according to the circuit pattern to be wired inside and the dimension between the terminals, the step of drilling the through hole 13 according to the same dimension, and inserting the winding mold into the through hole 13 It can be formed through a process of winding the edge of the hole 13 to expose the conductive foil 12 on the sheet surface to the back surface and a process of cutting the sheet along the outline of each base sheet 11.
2 has a step of drilling a plurality of through-holes 13 in accordance with the circuit pattern to be wired and the dimensions between the terminals in the outline of the substrate sheet 11 on the surface of the sheet. A step of bonding the conductor foil 12 to the surface of the sheet so as to connect the holes 13, a step of forming a portion of the conductor foil 12 covering each through-hole 13 from above the hole 13 and exposing it to the back surface of the sheet, and a substrate It can form through the process of cut | disconnecting a sheet | seat along the outline of the sheet | seat 11 for work.

  As shown in FIG. 5, the wiring module 1 of the present invention formed in this way has through holes 13 on the terminals 31, 31 of the circuit pattern 3 on the sheet 2 having the circuit pattern 3 formed on the surface. The wiring module 1 is integrated with the sheet 2 by a heating press so that the terminals 31 and 31 of the circuit pattern 3 are electrically connected to each other through the conductor foil 12 on the surface of the base sheet 11. Can be connected. Since the base sheet 11 is heat-sealed to the sheet 2 by the heating press, the wiring module 1 is integrally fixed to the upper surface of the sheet 2, and the end of the conductor foil 12 protrudes below the through hole 13. Therefore, the conductor foil 12 can be reliably connected to the terminal 31 when being hot-pressed. Moreover, since the conductor foil 12 which cross | intersects the circuit pattern 3 on both sides of the sheet | seat 11 for base materials is insulated by the sheet | seat 11 for base materials, the circuit pattern 3 does not short-circuit.

  When an inlet sheet for an IC tag is molded using the wiring module of the present invention, for example, as shown in FIG. 6, an antenna circuit pattern 3 is formed on the surface and an IC chip 4 is formed on the circuit pattern 3. The wiring module 1 is placed on the sheet 2 formed by connecting the wiring modules 1 so that the through holes 13 are placed on both terminals 31 and 31 of the antenna start point and end point. The protective sheets 5 can be overlaid, and the overlaid sheets can be formed by integrating them with a hot press. In this case, there is no need for an IC chip or solder bump for flip chip connection.

  Further, as shown in FIG. 7, the antenna circuit pattern 3 is formed on one surface of the core sheet 6 and the IC module 4 is mounted on the antenna circuit pattern 3 on the same, and the through hole 13 is the starting point of the antenna. The core sheet 7 is further overlapped and placed over both terminals 31 and 31 at the end points, and over 8 and 9 are respectively overlapped on the outer surfaces of both core sheets, and these overlapped sheets are integrated by a hot press. By cutting this into a predetermined contour shape, the IC tag on which the IC module is mounted can be formed by a series of steps for integrating the laminated sheets.

  Hereinafter, the Example which evaluated the module for wiring of this invention is described. In addition, this invention is not limited to the form of these Examples.

[Example 1]
A base sheet 11 made of PETG having a thickness of 100 μm and a length and width of 15 mm × 3 mm is perforated with 1 mm diameter through-holes 13 and 13 from the inside of both ends, and between the through-holes on the surface of the base sheet 11. A conductor foil 12 made of copper having a thickness of 18 μm and a width of 1.5 mm is bonded together by heat fusion, and the conductor foil 12 is immersed in the through holes 13 and 13 by forming, so that the conductor foil shown in FIG. A wiring module 1 </ b> A having 12 end portions curved in a dish shape projecting to the back side of the base material sheet 11 was produced. The center interval between the through holes 13 was set to 12 mm.
The copper foil was etched on the surface of one side of a 200 μm thick core sheet made of PETG to form an antenna circuit pattern 3. The distance between the antenna start and end terminals was set to 12 mm.
Then, the wiring module 1A is overlaid on the circuit pattern of the core sheet so that the through holes 13 and 13 are placed on the terminals of the antenna start point and end point, respectively, and a 200 μm thick core sheet made of PETG is placed thereon. The stacked sheets were integrated by heating and pressing.
Then, the integrated sheet was cut into a rectangular shape having a length of 28 mm and a width of 40 mm with a punching blade to produce a tag-shaped test card. Note that check terminals connected to the start point and end point of the antenna were provided at both ends of the sheet surface.

[Example 2]
The thickness of the conductor foil 12 is set to 35 μm, and the wiring module 1B shown in FIG. 4 (B) in which the end of the conductor foil 12 protrudes from the back side of the base sheet 11 is produced with the same dimensions as in Example 1. A tag-like test card using this was produced in the same manner as in Example 1.

Example 3
A conductive foil 12 made of copper having a thickness of 18 μm and a width of 2 mm is bonded to the center of the surface of the base sheet 11 made of PET having a thickness of 38 μm and vertical and horizontal dimensions of 15 mm × 3 mm from both ends of the sheet. 0.6 mm diameter through-holes 13, 13 were drilled, and the edge portions of the through-holes 13, 13 were folded back to the back side of the sheet by a winding process to produce the wiring module 1 shown in FIG. The center interval between the through holes 13 was set to 12 mm.
The copper foil was etched on the surface of one side of a 200 μm thick core sheet made of PETG to form an antenna circuit pattern 3. The distance between the antenna start and end terminals was set to 12 mm.
Then, the wiring module 1 is overlaid on the circuit pattern of the core sheet so that the through-holes 13 and 13 are placed on the terminals of the start point and end point of the antenna, respectively, and a 200 μm thick core sheet made of PETG is placed thereon. The stacked sheets were laminated by heating and pressing.
Then, the integrated sheet was cut into a rectangular shape having a length of 28 mm and a width of 40 mm with a punching blade to produce a tag-shaped test card. Providing a check terminal is the same as described above.

Example 4
A conductive foil 12 made of copper having a thickness of 18 μm and a width of 2 mm is bonded to the center of the surface of the base sheet 11 made of PETG having a thickness of 50 μm and a vertical and horizontal dimension of 15 mm × 3 mm from both ends of the sheet. 0.6 mm diameter through-holes 13, 13 were drilled, and the edge portions of the through-holes 13, 13 were folded back to the back side of the sheet by a winding process to produce the wiring module 1 shown in FIG. The center interval between the through holes 13 was set to 12 mm.
A copper foil was etched on the surface of one side of a 200 μm thick core sheet made of PETG to form an antenna circuit pattern. The distance between the antenna start and end terminals was set to 12 mm.
Then, the wiring module 1 is overlaid on the circuit pattern of the coart so that the through holes 13 and 13 are placed on the terminals of the antenna start point and end point, respectively, and a 200 μm thick core made of PCTG / PC alloy is placed thereon. The sheets were superposed and the laminated sheets were integrated by heating and pressing.
Then, the integrated sheet was cut into a rectangular shape having a length of 28 mm and a width of 40 mm with a punching blade to produce a tag-shaped test card. Providing a check terminal is the same as described above.

  The tag-like test card of each example was subjected to a fitting test on a rail and a bending test, and the conduction state of the antenna circuit connected via the wiring module was evaluated.

The fitting test to the rail was repeated 100 times for the tag holding rail with 28mm between the upper and lower ends and 30mm between the recesses, and then the test circuit was applied to the check terminal of the sheet. It was confirmed whether or not is disconnected.
In the test, the front of the rail is the front side (the inner layer antenna circuit is the back side of the rail, the wiring module is the front side of the rail), and the front of the rail is the back side (the inner layer antenna circuit is the front side of the rail). This was done for each of the cases where the wiring module was oriented to the back side of the rail).

In the bending test, both ends of the sheet are picked with fingers, the force is applied to the fingers to bend the sheet to approximately 90 degrees, the force is released and returned to its original state, and this is repeated 100 times. It was confirmed whether the circuit was disconnected.
The test was conducted for each of the case where the sheet was gripped on both ends of the sheet with the front side facing outward and the case where both ends of the sheet were gripped.

  As a result of both tests, disconnection of the internal circuit was not confirmed in all the examples. The results of each test are shown in Table 1. In the table, since the continuity of the internal circuit was confirmed in any test, “◯” is added to the evaluation column.

It is the top view and sectional drawing of the module for wiring of one Embodiment of this invention. (A), (B), (C) is the figure which showed the manufacturing process of the module for wiring of FIG. It is the top view and sectional drawing of the module for wiring of other embodiment of this invention. (A), (B) is an expanded sectional view of the through-hole part by different forming of the module for wiring of FIG. It is sectional drawing of the sheet | seat which connected the internal circuit using the module for wiring of this invention. It is sectional drawing of an example of the inlet sheet formed using the module for wiring of this invention. It is sectional drawing of an example of the IC tag formed using the module for wiring of this invention.

Explanation of symbols

1, 1A, 1B Wiring module, 11 Substrate sheet, 12 Conductor foil, 13 Through hole, 2 Sheet, 3 Circuit pattern, 4 IC chip, 5 Protection sheet, 6, 7 Core sheet, 8, 9 Oversheet

Claims (5)

A wiring module for electrically connecting internal circuit patterns of laminated sheets integrated by a heating press,
A laminated sheet circuit wiring module having a configuration in which a conductive foil is bonded to the surface of a base material sheet made of a thermoplastic resin, and the conductive foil protrudes to the back side of the sheet through a through hole formed in the sheet.   A conductive foil is formed by forming a through hole penetrating to the back surface of the sheet on the conductive foil of the base sheet having the conductive foil bonded to the surface and folding the edge of the through hole from the sheet surface side to the sheet back surface side. The laminated sheet circuit wiring module according to claim 1, wherein the sheet is protruded toward the back side of the sheet.   A through-hole is formed in the sheet for the base material, and the conductive foil is bonded to the surface of the sheet by covering the through-hole, and the conductive foil protrudes to the back side of the sheet by immersing the conductive foil in the through-hole. The laminated sheet circuit wiring module according to claim 1.   4. The wiring module according to claim 1, wherein the wiring module is placed on a sheet having a circuit pattern formed on a surface thereof so that the through hole is placed on the circuit pattern, and the wiring module is heated and pressed. An internal circuit connection structure of an IC tag in which circuit patterns are electrically connected to each other via a wiring module by integrating the circuit board into a sheet. The wiring module according to any one of claims 1 to 3, wherein an IC chip is mounted on the surface of the sheet and the terminal thereof is connected to the conductor foil, and the through hole is formed on the sheet on which the circuit pattern of the antenna is formed on the surface. Is an internal circuit connection structure of an IC tag in which an IC chip and an antenna are electrically connected by arranging and superimposing them so as to be placed on both end circuit patterns of the antenna and integrating the wiring module on the sheet by a heating press.

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