JP2007295505A - Film-type antenna and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film-type antenna which can constitute a metal circuit having a low resistance value and providing improved antenna performance, enables circuit width thereof to be suppressed to a specified level or under, to maintain transparency of films and proper appearance, and can be produced easily and at low cost, without requiring high-accuracy metal mold or plotter. <P>SOLUTION: An antenna circuit 10 is configured, by arranging a recessed groove 3 extending along an antenna circuit forming position on the surface of a film substrate 2 and fitting an electric wire 4, constituted of a metal wire material into the recessed groove 3. The film substrate 2 is constituted of an antenna film layer 21, an adhesive layer 22, a core film layer 23, an adhesive layer 24, and a release paper layer 25 and the electric wire 4 is stuck and fixed on the adhesive layer 22 at the bottom part of the recessed groove 3. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a film-type antenna that is attached to a windshield or rear glass of an automobile and that is suitable as an antenna for receiving TV radio waves and VICS information, and a method for manufacturing the same.

  In recent car navigation systems for automobiles, not only the navigation function but also TV radio waves and VICS information are received and the functions are expanded to improve the quality of service. The antenna that plays a role in these functions is exposed to the risk of damage and theft if it is mounted outside the car body, and if it is installed on the dashboard in the car, it may damage the aesthetics. The spread of film-type antennas to be attached to the inner surface is progressing.

  As a conventional film-type antenna, an adhesive layer for attaching to a windshield is formed on one surface side of a strip-shaped transparent film, and an antenna conductor is formed on the other surface side by pattern printing. The thing pasted on the side of a windshield is proposed (for example, refer to patent documents 1). As described above, most of the conventionally proposed film-type antennas have a circuit formed by printing conductive plastic. However, such a conductive plastic circuit has a large resistance value compared to an antenna having a metal circuit, and has a limit in antenna performance. In addition, many conductive plastics have a dark color, and there is a problem that an uncomfortable feeling and an uncomfortable feeling are caused by the antenna circuit entering the field of view.

  Therefore, in recent years, as a method of forming a metal circuit on a film, a method of forming a circuit by punching a metal foil with a mold, a method of forming a circuit by arranging conductors with a plotter, a circuit by etching a metal layer Film-type antennas that have metal circuits manufactured by the method of forming the film have begun to be marketed. However, from the standpoint of maintaining visibility, the antenna circuit width specified by the Road Traffic Act is limited to 0.4 mm or less, and film In addition to technical issues such as maintaining transparency and improving appearance, there are problems such as investment costs of expensive high-precision molds and investment costs of expensive plotters, and still a film type that uses metal circuits The spread of antennas is not progressing.

  JP 2000-342020 A

  Therefore, in view of the above-mentioned situation, the present invention intends to solve the problem that it is possible to construct a metal circuit that has a small resistance value and can improve the antenna performance, and that the circuit width is kept below the specified value, and the film transparency and the good appearance are maintained. It is possible to provide a film type antenna that can be easily manufactured at low cost without requiring a highly accurate mold or plotter, and a method for manufacturing the same.

  In order to solve the above-mentioned problems, the present invention provides a concave groove extending along the antenna circuit formation position on the film substrate surface, and configures an antenna circuit by fitting an electric wire made of a metal wire into the concave groove. A film type antenna characterized by the above was constructed.

  Here, the film base is composed of an antenna film layer and an adhesive layer on the back side thereof, and the groove is formed by continuously penetrating a predetermined width of the antenna film layer along the antenna circuit forming position. Is preferably formed and attached to the adhesive layer on the back surface side constituting the bottom of the groove.

  Moreover, what provided the cover layer which block | closes the opening part of the said ditch | groove at least on the film base material surface which fitted the said electric wire is preferable.

  Furthermore, the electric wire is a bare electric wire made of a metal wire or an insulating electric wire coated with an insulating film, and the insulating film is preferably colored in a predetermined color. Specifically, those made of a metal stranded wire are preferable. Moreover, a connection terminal can be provided in the terminal part extended outside the said ditch | groove in the said electric wire.

  The present invention also relates to a method of manufacturing each of the above film-type antennas, the step of forming a groove that extends along the antenna circuit formation position on the film substrate surface, and a metal wire in the groove. The manufacturing method provided with the electric wire mounting process which inserts the electric wire which consists of is also provided.

  Here, the film base is composed of an antenna film layer and an adhesive layer on the back side thereof, and the concave groove forming step is along the antenna circuit formation position of the antenna film layer attached to the adhesive layer. A grooving step of continuously forming two parallel kerfs penetrating the antenna film layer from the front surface side, removing the antenna film layer having a predetermined width between the kerfs, and removing the adhesive layer on the bottom A method comprising a removing step of exposing the substrate is preferable. In particular, it is preferable that the grooving step includes press working with a mold having a cutting blade.

  Further, the film base is composed of an antenna film layer and an adhesive layer on the back surface side thereof, and the concave groove forming step forms an adhesive film having a smaller adhesive force than the adhesive layer on the surface side of the antenna film layer. A grooving step of continuously forming two parallel kerfs that penetrate the antenna film layer along the antenna circuit formation position from the back side of the antenna film layer, and a predetermined interval between the kerfs A removal step of removing the antenna film layer having a width and exposing the adhesive film on the bottom, a bonding step of attaching the adhesive layer to the back side of the antenna film layer, and a peeling step of peeling off and removing the adhesive film A method comprising In particular, it is preferable that the grooving step includes press working with a mold having a cutting blade.

  Further, the film base is composed of an antenna film layer and an adhesive layer on the back surface side thereof, and the concave groove forming step forms an adhesive film having a smaller adhesive force than the adhesive layer on the surface side of the antenna film layer. A groove forming step of forming a groove having a predetermined width that penetrates the adhesive film and the antenna film layer along the antenna circuit forming position; and attaching the adhesive layer to the back side of the antenna film layer, A method comprising a bonding step for forming a concave groove in which the adhesive layer is located at the bottom and a peeling step for peeling off and removing the adhesive film is preferable. In particular, it is preferable that the groove forming step includes a punching process using a mold.

  Further, a cover step of providing a cover layer for closing at least the opening of the concave groove on the film base surface into which the electric wire is fitted, and a pressing step of hot pressing the concave portion of the film base material into which the electric wire is fitted. It is preferable to provide.

  According to the present invention as described above, since the antenna circuit is configured by fitting the electric wire made of the metal wire into the groove, the resistance value is small compared with the conventional conductive plastic circuit, and the antenna performance is greatly improved. it can. In addition, it can be easily manufactured simply by fitting the electric wire into the groove, and the antenna circuit with a more uniform and narrower width is more accurate than the conventional method of forming a circuit by punching a metal foil or wiring a conductor with a plotter. Well, it can be manufactured at low cost.

  Also, a concave groove is formed by continuously cutting and cutting a predetermined width of the antenna film layer along the antenna circuit formation position, and the electric wire fitted in the adhesive layer on the back surface side constituting the bottom of the concave groove Is attached and fixed, so that the equipment cost is less than that of the conventional printing method and punching of metal foil, and it can be easily manufactured.

  In addition, since a cover layer that covers at least the opening of the groove is provided on the film base surface into which the wire is fitted, the adhesion stability of the wire in the groove is improved, and the gap between the groove and the wire is increased. It is possible to prevent dust from collecting around the antenna circuit.

  In particular, when using an insulated wire as an electric wire, the insulation film of the insulated wire is colored in a predetermined color and harmonized with the blue sky and clouds that can be seen from the windshield and rear glass to alleviate the discomfort and discomfort of the antenna circuit. Can do. As a color to be colored, for example, it is desirable to use light blue or light gray that can realize the above-mentioned harmony.

  Further, since the electric wire is made of a stranded wire, the surface area of the antenna circuit can be increased to improve the radio wave reception capability, that is, the antenna capability.

  In addition, a connection terminal can be provided in the terminal portion that extends outside the concave groove of the electric wire, and a connection terminal that can obtain good electrical connection can be easily configured. Thus, the electric wire used as an antenna circuit can be used as an antenna as it is. By pulling out to the outside, the choice of external connection will increase.

  Further, the concave groove forming step continuously forms two parallel kerfs that penetrate the antenna film layer from the surface side along the antenna circuit formation position of the antenna film layer attached to the adhesive layer. Since there is a grooving step and a removal step of removing the antenna film layer having a predetermined width between the kerfs and exposing the adhesive layer on the bottom, the width can be accurately adjusted only by forming the kerf of the antenna film layer. A narrow circuit can be easily manufactured, and in particular, the grooving step can be efficiently performed by press working with a die having a cutting blade.

  In addition, the concave groove forming step attaches a pressure-sensitive adhesive film having an adhesive force smaller than that of the adhesive layer to the surface side of the antenna film layer, and the antenna film layer is formed along the antenna circuit formation position from the back side of the antenna film layer A grooving step of continuously forming two parallel kerfs passing therethrough, a removing step of removing the antenna film layer having a predetermined width between the kerfs and exposing the adhesive film on the bottom, and the antenna film Since it has a bonding step for attaching the adhesive layer to the back side of the layer and a peeling step for peeling off and removing the adhesive film, the adhesive layer is not touched by a cutting blade or the like and does not become white In addition, a clean and beautiful state can be maintained, and the precision of the grooving depth by controlling the operation amount of the cutting blade does not have to be so high, and the manufacture becomes easy.

  Further, in the groove forming step, a pressure-sensitive adhesive film having an adhesive force smaller than that of the adhesive layer is attached to the surface side of the antenna film layer, and the adhesive film and the antenna film layer are penetrated along the antenna circuit formation position. A groove forming step for forming a groove having a width, a bonding step for forming a concave groove in which the adhesive layer is located on the bottom by attaching the adhesive layer to the back side of the antenna film layer, and the adhesive film. Since the peeling process for peeling and removing is provided, the production becomes easier, and the efficiency can be improved as the punching process using a mold.

  Moreover, since the press process which heat-presses on the concave groove | channel of the film base material which fitted the electric wire is provided, the adhesive stability of an electric wire increases. In this case, when a hot melt adhesive is used as the adhesive layer, an adhesive force can be imparted by this hot pressing.

  Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1A is a plan view showing a film type antenna according to the present invention. FIGS. 1 to 6 show typical embodiments. In the figure, reference numeral 1 denotes a film type antenna, 2 denotes a film base material, 3 denotes The concave grooves 4 indicate electric wires.

  As shown in the plan view of FIG. 1 and the cross-sectional view of FIG. 2, the film-type antenna 1 of the present invention is provided with a concave groove 3 extending along an antenna circuit formation position on the surface of the film substrate 2, and the concave groove The antenna circuit 10 is configured by fitting an electric wire 4 made of a metal wire material 3 into the antenna circuit 10.

  More specifically, as shown in FIG. 2, the film substrate 2 is composed of an antenna film layer 21 and an adhesive layer 22 on the back side thereof, and a predetermined width of the antenna film layer 21 is continuously provided along the antenna circuit formation position. The concave groove 3 is formed by cutting through and cutting, and the fitted electric wire 4 is adhered and fixed to the adhesive layer 22 on the back surface side constituting the bottom of the concave groove 3.

  In the present embodiment, a core film layer 23 is formed below the adhesive layer 22, an adhesive layer 24 is attached below the core film layer 23, and a release paper layer 25 is further laminated thereon to form the film base 2 Is configured.

  The antenna film layer 21 is a transparent polyester film having a thickness of 0.025 to 0.1 mm, and the adhesive layer 22 is a layer made of an adhesive such as a transparent adhesive or hot melt having a thickness of 0.03 to 0.1 mm. It is. Similarly to the antenna film layer 21, the core film layer 23 is a transparent polyester film having a thickness of 0.025 to 0.1 mm, and the underlying adhesive layer 24 is a transparent adhesive having a thickness of 0.03 to 0.1 mm. It is a layer made of an agent. The adhesive layers 22 and 24 may be double-sided tape or the like.

  The core film layer 23 and the adhesive layer 24 may be omitted, and the back surface side of the adhesive layer 22 may be directly adhered to the glass surface and attached. Alternatively, the adhesive layer 24 may be omitted, and the electric wire fitted in the groove may be covered and fixed with a cover film, or may be fixed by melting the concave groove by hot pressing.

  The concave groove 3 into which the electric wire 4 is fitted is provided with a width of 0.4 mm or less and a depth the same as that of the antenna film layer 21 (0.025 to 0.1 mm), where the width or outer diameter is 0.4 mm. A metal antenna circuit 10 is configured by fitting the following electric wires 4. Note that the bottom adhesive layer 22 can also be recessed so that the depth of the groove 3 can be increased.

  As the electric wire 4, a bare electric wire made of a metal wire as shown in FIG. 2 or an insulated electric wire obtained by coating the bare electric wire with an insulating film 40 as shown in FIG. In particular, the bare wire may be a single wire, but a metal stranded wire may be used as a metal stranded wire to increase the surface area and improve the radio wave receiving ability.

  When an insulated wire is used as the wire 4 as shown in FIG. 5A, it is preferable to adjust the color and tone of the insulating film 40 to alleviate the feeling of discomfort and discomfort of the antenna circuit 10. Specifically, the insulating film 40 is preferably colored light blue or light gray, so that, as shown in FIG. 6, when the insulating film 40 is mounted on the windshield or rear glass 80 of the vehicle 8, In harmony with the cloud, the presence of the antenna circuit 10 can be made inconspicuous, and good visibility can be maintained.

  In this example, a metal circuit is fitted on the film substrate 2 and then fixed by hot pressing or the like, but as shown in FIG. 2B, the cover layer has a thickness of 0.012 to 0.1 mm. A coverlay film 5 made of a polyester film may be adhered to prevent the electric wires 4 from falling off. This makes it possible to omit heat pressing and the like, and improves adhesion stability and prevents dust from collecting around the antenna circuit such as the gap between the concave groove 3 and the electric wire 4.

  Such a coverlay film 5 is preferably affixed to substantially the entire surface of the film substrate 2, but is partially affixed as long as it covers at least the opening of the groove 3 in which the electric wire 4 is mounted. Alternatively, a cover layer may be provided by spraying or printing instead of the film-like cover layer.

  Next, a first example of a method for manufacturing the film type antenna 1 according to the present embodiment will be described with reference to FIG. The manufacturing method of this example mainly includes a concave groove forming step S1 and a wire mounting step S2.

  The concave groove forming step S1 includes two parallel lines penetrating the antenna film layer 21 from the surface side along the antenna circuit formation position of the antenna film layer 21 as shown in FIGS. A grooving step S11 for continuously forming the kerfs 30 and 30, and a removing step S12 for removing the antenna film layer 21a having a predetermined width between the kerfs 30 and 30 and exposing the adhesive layer 22 to the bottom 31. It becomes more.

  The grooving step S11 can be performed by pressing with the mold 6 provided with the cutting blade 60, and the cutting blade 60 has a length that sufficiently penetrates the antenna film layer 21 in the pressed state shown in FIG. The film substrate 2 is half-cut, and in the removing step S12, the antenna film layer 21a separated by the cut blade 60 is peeled off, and the concave groove 3 is formed.

  In the electric wire mounting step S2, as shown from (d) to (e) in the figure, the electric wire 4 is fitted with a finger along the concave groove 3 formed in the step S1, and the adhesive layer 22 of the bottom 31 is bonded. This is a step of fixing by force, and the electric wire 4 is wired using the adhesiveness of the adhesive layer 22. The electric wire 4 may be temporarily placed on the concave groove 3 and pressed from above to be fitted.

  And after fitting and fixing as shown to (e) in a figure, the fixing state of the electric wire 4 is stabilized by hot press etc. As shown in FIG. When the adhesive layer 22 is composed of a hot melt adhesive, it is fixed by this heat.

  After the electric wire 4 is mounted, the connection terminal 7 is provided at the terminal. In this example, as shown in FIG. 1, the terminal of each electric wire is connected to a conductive film-like connection terminal 70 provided on the surface of the film base 2, and a connector at the end of the coaxial cable extending from an external antenna amplifier or the like is used. Although what is crimped | bonded is illustrated, More preferably, as shown in FIG. 5, it can be set as the structure formed by drawing out the electric wire 4 to the exterior of the film base material 2, and attaching the connection terminal which is not shown in figure.

  5A shows the case of the insulated wire 4, and FIG. 5B shows the case of the bare wire. In the insulated wire 4a, the insulation film at the end of the wire 4 drawn to the outside can be peeled off and a terminal (not shown) can be hit. In the bare wire of FIG. It is desirable to leave a portion covering the base end portion of the electric wire 4 from which the base material 2 is drawn out, and cover the portion together with the heat shrinkable tube 71 together with the electric wire 4 and then hit a connection terminal (not shown). In addition, a method of connecting to a substrate without hitting a terminal, or soldering directly to a connector pin can be used.

  Next, a second example of the method for manufacturing the film type antenna 1 according to this embodiment will be described with reference to FIG. The manufacturing method of this example is the same as the first example in that it includes a concave groove forming step S1 and an electric wire mounting step S2, but the concave groove forming step S1 is different.

  In the groove forming step S1 of this example, as shown in (a) to (c) of the figure, the adhesive film 26 is attached to the front surface side of the antenna film layer 21, and the antenna circuit is formed from the opposite back surface side. A grooving step S11 for continuously forming two parallel kerfs 30 and 30 penetrating the antenna film layer 21 along the gap between the kerfs 30 and 30 as shown in FIGS. The removal step S12 for removing the antenna film layer 21a having a predetermined width and exposing the adhesive film 26 at the bottom, and the back side of the antenna film layer 21 (adhesive film 26 and It consists of a bonding step S13 for attaching the adhesive layer 22 to the opposite side, and a peeling step S14 for peeling off and removing the adhesive film 26 as shown in FIGS. The adhesive film 26 has a lower adhesive force than the adhesive layer 22, and there is no fear that the antenna film layer 21 is peeled off from the adhesive layer 22 in the peeling step S <b> 14.

  As in the first example, the grooving step S11 and the removing step S12 are performed by pressing with the mold 6 having the cutting blade 60, and the separated antenna film layer 21a is removed. In the first example, the antenna film layer was cut from the surface side of the antenna film layer 21 previously bonded to the adhesive layer 22, whereas in this example, the antenna film layer bonded to the adhesive film 26 to be peeled off later. It is cut and peeled off from the back side of 21.

  The bonding step S13 and the peeling step S14 are steps of attaching the grooved antenna film layer 21 on the adhesive layer 22 and forming the concave groove 3 in which the adhesive layer 22 is located at the bottom 31. First example Unlike the case, the adhesive layer 22 is not touched by the cutting blade 60, and a clean and beautiful state is maintained. The wire mounting step S2 and other points are the same as in the first example.

  In this example, the grooving step S11 and the removing step S12 remove only the antenna film layer 21a as in the first example. However, as another method, both the adhesive film 26 and the antenna film layer 21 are penetrated. A groove having a predetermined width may be formed. In this case, the groove can be easily formed by punching with a mold.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and can of course be implemented in various forms without departing from the gist of the present invention.

(A), (b) is a top view which shows the film type antenna which concerns on typical embodiment of this invention. (A), (b) is sectional drawing of the principal part similarly. (A)-(e) is explanatory drawing which similarly shows the 1st manufacturing method of an antenna type film. (A)-(g) is explanatory drawing which similarly shows the 2nd manufacturing method. (A), (b) is explanatory drawing which similarly shows the connection terminal part of a film type antenna. Explanatory drawing which similarly shows the state which attached the film type antenna to the glass of a motor vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Film type antenna 2 Film base material 3 Groove 4 Electric wire 5 Coverlay film 6 Mold 7 Connection terminal 10 Antenna circuit 21 Antenna film layer 21a Antenna film layer 22 Adhesive layer 23 Core film layer 24 Adhesive layer 25 Release paper layer 26 Adhesion Film 30 Cut groove 31 Bottom 40 Insulating film 60 Cutting blade 70 Connection terminal 71 Heat shrinkable tube

Claims (16)

  A film-type antenna comprising an antenna circuit formed by providing a concave groove extending along an antenna circuit formation position on a film substrate surface and fitting an electric wire made of a metal wire into the concave groove.   The film base is composed of an antenna film layer and an adhesive layer on the back side thereof, and the groove is formed by continuously cutting through a predetermined width of the antenna film layer along the antenna circuit formation position. 2. The film type antenna according to claim 1, wherein an inserted electric wire is attached and fixed to the adhesive layer on the back surface side constituting the bottom of the concave groove.   The film-type antenna according to claim 1 or 2, wherein a cover layer for closing at least the opening of the concave groove is provided on the film substrate surface into which the electric wire is fitted.   The film-type antenna according to any one of claims 1 to 3, wherein the electric wire is a bare electric wire made of a metal wire or an insulated electric wire coated with an insulating film.   The film type antenna according to claim 4, wherein the insulating film is colored in a predetermined color.   The film antenna according to any one of claims 1 to 5, wherein the electric wire is made of a stranded metal wire.   The film type antenna according to any one of claims 1 to 6, wherein a connection terminal is provided in a terminal portion extending outside the concave groove in the electric wire.   8. A concave groove forming step of providing a concave groove extending along an antenna circuit forming position on the film substrate surface, and an electric wire mounting step of fitting an electric wire made of a metal wire into the concave groove. The manufacturing method of the film type | mold antenna of any one.   The film base is composed of an antenna film layer and an adhesive layer on the back side thereof, and the concave groove forming step is performed along the antenna circuit formation position of the antenna film layer attached to the adhesive layer. A grooving step of continuously forming two parallel kerfs penetrating the antenna film layer from the side, the antenna film layer having a predetermined width between the kerfs is removed, and the adhesive layer is exposed at the bottom The manufacturing method of the film type antenna of Claim 8 which consists of a removal process.   The method for manufacturing a film-type antenna according to claim 9, wherein the grooving step includes press working with a mold having a cutting blade.   The film base is composed of an antenna film layer and an adhesive layer on the back side thereof, and the concave groove forming step attaches an adhesive film having a smaller adhesive force than the adhesive layer to the surface side of the antenna film layer. A grooving step of continuously forming two parallel kerfs that penetrate the antenna film layer along the antenna circuit formation position from the back side of the antenna film layer, and a predetermined width between the kerfs. From the removing step of removing the antenna film layer and exposing the adhesive film on the bottom, the attaching step of attaching the adhesive layer to the back side of the antenna film layer, and the peeling step of peeling off and removing the adhesive film The method for producing a film-type antenna according to claim 8.   The method for manufacturing a film-type antenna according to claim 11, wherein the grooving step includes press working with a die having a cutting blade.   The film base is composed of an antenna film layer and an adhesive layer on the back side thereof, and the concave groove forming step attaches an adhesive film having a smaller adhesive force than the adhesive layer to the surface side of the antenna film layer. A groove forming step of forming a groove having a predetermined width passing through the adhesive film and the antenna film layer along the antenna circuit forming position, and attaching the adhesive layer to the back side of the antenna film layer, thereby The manufacturing method of the film type antenna of Claim 8 which consists of the joining process which comprises the ditch | groove in which this contact bonding layer is located, and the peeling process which peels and removes the said adhesive film.   The method for manufacturing a film-type antenna according to claim 13, wherein the groove forming step includes punching with a mold.   The manufacturing method of the film type antenna of any one of Claims 8-14 provided with the cover process which provides the cover layer which plugs up the opening part of the said ditch | groove at least on the film base material surface which fitted the said electric wire. .   The manufacturing method of the film type antenna of any one of Claims 8-15 provided with the press process of heat-pressing on the concave groove of the film base material which fitted the said electric wire.

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