JP2001119219A - Antenna sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna sheet capable of repeatedly and easily being peeled off and adhered again from/to an adherend after being adhered to the object adhered. SOLUTION: An antenna element composed of a conductive material is formed on one face of a base material sheet, its end is provided with a terminal part for connecting an antenna feeder, and an adhesive layer having re- peelability and re-sticking property is formed on the face on which the antenna element is formed or the opposite face of the base material sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna sheet which can be attached to a window glass of an automobile and used for receiving or transmitting radio waves.

[0002]

2. Description of the Related Art Conventionally, it has been known to attach an antenna sheet having an adhesive layer to a window glass of an automobile in order to receive radio waves such as radio waves and television waves. This antenna sheet has an antenna element made of a conductive substance formed on the surface of a base sheet, and an adhesive layer formed on the other surface of the base sheet. However, since the layer to be attached to the window glass of the car does not consider the removability, it can be replaced when the sticking position shifts, or when replacing the old car window glass when replacing the old car window glass. It was difficult to re-paste to another location such as re-placing on a surface.

[0003]

SUMMARY OF THE INVENTION According to the present invention, it is possible to repeatedly perform easy peeling from an adherend and reattachment to the adherend after sticking, thereby preventing contamination of the adherend. An object of the present invention is to provide an antenna sheet that can be used.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, formed an antenna element made of a conductive substance on one surface of a base sheet, and By forming an adhesive layer having removability and re-adhesive property on the surface on which is formed or on the opposite surface, it has been found that peeling and adhering to an adherend can be easily performed, and in order to complete the present invention. Reached. That is, in the present invention, an antenna element made of a conductive substance is formed on one surface of a base sheet, and a terminal portion for connecting an antenna feeder is provided at an end thereof, and the antenna element of the base sheet is formed. Another object of the present invention is to provide an antenna sheet characterized by forming an adhesive layer having removability and re-adhesive property on the surface or the opposite surface. Further, in the present invention, in the above antenna sheet, the adhesive layer has a 100% modulus of 6 ×.
An object of the present invention is to provide an antenna sheet which is a polyurethane elastomer layer having a strength of 10 ⁶ N / m ² or less and a breaking strength of 2 × 10 ⁷ N / m ² or more. Further, the present invention provides an antenna sheet in which, in the above antenna sheet, a strong adhesive layer and a resin sheet are laminated on a base sheet, and an adhesive layer is formed on the surface of the resin sheet.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION In the antenna sheet of the present invention, various plastic sheets,
Although a film can be used, a film having heat resistance enough to withstand the curing temperature at the time of forming an antenna element using a conductive substance is preferable. Specific examples of the base sheet include, for example, polyolefins such as polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyesters such as polybutylene terephthalate, polyvinyl chloride, polyurethane, polycarbonate, polyamide, polyimide, and various synthetic resins such as fluororesins. Sheet,
A film and a sheet and a film made of polyethylene terephthalate or polypropylene are particularly preferable because of high strength and low cost. The base sheet is
It may be a single layer or a multilayer of two or more layers of the same type or different types. The base sheet is preferably transparent or translucent, and particularly preferably transparent, in order to obtain the visibility of the window glass because it is attached to a window glass of an automobile or the like. The thickness of the substrate sheet is not particularly limited, but may be generally 20 to 500 μm, and preferably 40 to 250 μm.

The antenna element formed on one side of the base sheet is made of a conductive material. As the conductive substance, for example, a conductive paste in which particles of a metal such as gold, silver, nickel, or copper are dispersed in a binder can be used. The formation of the antenna element on one side of the base sheet can be performed by attaching a conductive paste to the antenna pattern shape by means such as printing or coating. Silver is particularly preferable as the metal used for the conductive paste. The average particle size of the metal particles is preferably from 1 to 15 μm, particularly preferably from 2 to 10 μm. Examples of the binder include a polyester resin, a polyurethane resin, an epoxy resin, and a phenol resin. The weight ratio between the metal particles and the binder is preferably from 95: 5 to 80:20, and more preferably from 93: 7 to 85:15.

[0007] The conductive paste includes printability, applicability, etc.
It is preferable to add a solvent in order to increase the viscosity. Solvent and
Then, a general solvent can be used. Conductive pen
The thickness of the antenna element formed by the
The thickness is preferably 3 to 50 μm, particularly preferably 8 to 20 μm.
Good. In addition to the conductive paste, for example, metal foil or steam
Conductivity of deposited thin film by sputtering, metal simple substance etc.
It may be used as a substance. Use of conductive paper
In addition to the metal used for the strike, aluminum
Wear. The resistivity (resistivity) of the antenna element is determined by the four-terminal method.
Measured by 10^-4-10 ^-6Ω · cm is preferred.
The shape of the antenna element is radio, TV, mobile phone, etc.
Antenna that can receive or transmit various radio waves
Although there is no particular limitation as long as it does, for example, as shown in FIG.
Things.

[0008] The surface of the conductive antenna element may be covered with a protective substance such as a resist. The protective substance is for imparting waterproofness, insulation, abrasion resistance and the like of the antenna element. It is preferable that the protective substance is transparent like the base sheet. Examples of the resist include those formed of a resist ink containing one or two kinds of ultraviolet curable resin and thermosetting resin, preferably a resist containing an ultraviolet curable resin. Examples of the ultraviolet curable resin include one or a mixture of two or more of urethane acrylate, epoxy acrylate, polyester acrylate, polyether acrylate, polyol acrylate, and epoxy resin. It is preferable to mix a photoinitiator with the ultraviolet curable resin. Examples of the thermosetting resin include one or a mixture of two or more of polyester resin, polyurethane resin, phenol resin, epoxy resin, vinyl resin, and acrylic resin.

The coating with the resist ink can be performed by means such as printing and coating. The resist may be applied to almost the entire surface of the base sheet, or may be coated so as to have a width slightly wider than the antenna element. However,
The resist is not coated on the terminal portion for connection with the feeder wire. The terminal portion can be connected to a receiving device or a transmitting device such as a radio, a television, or a navigation system by a cord such as a feeder line. The thickness of the protective substance coating layer is not particularly limited, but is usually 1 to 30.
μm, and preferably 5 to 20 μm. At the end of the antenna element, a terminal for connecting an antenna feeder is provided. This terminal portion is also made of a conductive material, and is made of the same material as the conductive material forming the antenna element.

In the antenna sheet of the present invention, an adhesive layer is formed on the surface of the base sheet on which the antenna elements are formed or on the opposite surface. Examples of the material used for the adhesive layer include a urethane resin, an acrylic resin, a polyester resin, and a rubber-based resin, and a urethane resin made of a polyurethane elastomer is particularly preferable. The polyurethane elastomer is composed of a hard segment composed of a soft segment having a long-chain polyol as a main component, a diisocyanate, and a chain extender.As the long-chain polyol, a polyester polyol and a polyether polyol are mainly used. As diisocyanates, TDI (tolylene diisocyanate), Pure MD
I (diphenylmethane diisocyanate), HDI (hexamethylene diisocyanate) and the like are used. As the chain extender, a low molecular weight polyhydric alcohol, an aromatic diamine, or the like is used.

The type of polyurethane elastomer is a one-pack type obtained by diluting a long-chain polyol and a thermoplastic polyurethane elastomer obtained by polymerizing diisocyanates such as TDI and MDI with an organic solvent, or a polyurethane elastomer or a prepolymer thereof. And a two-pack type, in which a crosslinking agent such as polyisocyanate is added later and cured. The polyisocyanate used for the crosslinking agent is preferably an aliphatic or alicyclic polyisocyanate from the viewpoint of weather resistance. It is preferable to add a crosslinking accelerator to the two-pack type. In addition, a moisture-curing type that reacts isocyanate with moisture in the air,
A hot melt type polyurethane elastomer of a hot melt extrusion type may be used.

Other polyurethane elastomers include those obtained by reacting the following polyol with an organic diisocyanate. Examples of the polyol include propylene glycol, ethylene glycol or those obtained by addition polymerization of propylene oxide or ethylene oxide, polyether diols such as polytetramethylene ether glycol, ethylene glycol, propylene glycol, and 1,4-butanediol. Polyester glycols obtained by dehydration-condensation of low molecular glycols with organic acids such as adipic acid and phthalic acid, and the like. Aromatic diisocyanates such as 4,4′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, hexamethylene diisocyanate Isocyanate, isophorone diisocyanate,
4,4′-dicyclohexylmethane diisocyanate,
Examples thereof include aliphatic or alicyclic diisocyanates such as xylylene diisocyanate, and dimers, trimers, and carbodiimide modified products thereof. From the viewpoint of weather resistance, an aliphatic or alicyclic diisocyanate is preferred.

In the present invention, the adhesive layer has removability and re-adhesiveness. The adhesive strength of such an adhesive layer is preferably in the range of 0.03 to 5.0 N / 25 mm, particularly preferably in the range of 0.07 to 0.5 N / 25 mm.
The adhesive layer preferably has a 100% modulus of 6 × 10 ⁶ N / m ² or less, particularly 2 × 10 ⁶ to 4 × 10 ^6.
It is preferably N / m ² . A polyurethane elastomer having a 100% modulus of more than 6 × 10 ⁶ N / m ² has too small a sticking force to an adherend and may not be able to be stuck or re-stuck. 100% modulus is 2 × 1
If it is less than 0 6 ^{N /} m ^2, there is a possibility of contaminating the adherend upon re-stripping. The adhesive layer has a breaking strength of 2 ×
It is preferably at least 10 ⁷ N / m ² , especially 3 × 1
0 ⁷ is preferably ^{~1 × 10 8 N / m 2} . Further, the adhesive layer is preferably transparent. In the present invention, the thickness of the adhesive layer is not particularly limited, and may be generally in the range of 5 to 50 μm, preferably in the range of 8 to 25 μm.

Further, a release sheet may be provided to protect the above-mentioned adhesive layer. As the release sheet, for example, a conventionally known protective sheet having high smoothness may be used in order to maintain the smoothness of the polyurethane elastomer layer serving as the adhesive layer. Examples of such a release sheet include, for example, those subjected to release treatment on mirror-coated coated paper, those subjected to mirror-treated polyolefin melt extrusion coated paper alone or those subjected to release treatment, polyethylene terephthalate film, and polypropylene film. It is preferable to use a high synthetic resin film alone or one subjected to a release treatment. The release treatment may be a conventionally known one, and examples of the release agent include a silicone resin, an alkyd resin,
Silicone / alkyd copolymer resin, polyethylene,
Polypropylene alone or mixture, silicone / P
VA mixtures and the like. The thickness of such a release sheet is not particularly limited, but is preferably 25 to 200 μm.

The adhesive layer may be formed directly on the surface of the base sheet, or may be formed on the surface of the base sheet via any layer. The antenna sheet of the present invention has a base sheet on which an antenna element and a terminal portion are formed on one side, an adhesive layer provided on one side of another resin sheet, and a strong adhesive layer provided on the other side. It is preferable to manufacture the laminated sheet by bonding the surface of the base material sheet on which the antenna element and the terminal portion are formed or the opposite surface thereof to the surface of the strong adhesive layer, since it is easy to manufacture. Therefore, in this case, a strong adhesive layer and a resin sheet are laminated on the base sheet, and an adhesive layer is formed on the surface thereof. That is, the adhesive layer is formed on one side of the base sheet via the strong adhesive layer and the resin sheet. Such a laminated sheet may be attached to the entire surface of the base sheet on which the antenna element and the terminal portion are formed, or may be attached in a form excluding a part thereof. For example, it is preferable to attach the laminated sheet to the entire surface except for the positions of the terminal portions of the base sheet, since connection with the antenna feeder is facilitated.

The strong adhesive used in the strong adhesive layer includes, for example, a natural rubber-based adhesive, a synthetic rubber-based adhesive, an acrylic resin-based adhesive, a polyvinyl ether-based adhesive, a urethane resin-based adhesive, and silicone. Resin-based adhesives and the like are included. It is preferable that the strong adhesive layer is transparent like the base sheet. The thickness of the strong pressure-sensitive adhesive layer is not particularly limited, but may be usually 10 to 200 μm, preferably 15 to 4 μm.
0 μm. The adhesive strength of the strong adhesive layer is preferably at least three times the adhesive strength of the adhesive layer.

As the resin sheet, those similar to the above-mentioned base sheet can be used. The resin sheet preferably has transparency. The thickness of the resin sheet is not particularly limited, but is preferably from 10 to 100 μm. The adhesive layer and the strong pressure-sensitive adhesive layer can be formed by various methods, and various methods can be used without any particular limitation. For example, an air knife coater, a blade coater, a bar coater, a gravure coater, and a roll Coater, curtain coater,
Die coater, knife coater, screen coater,
Examples include a Meyer bar coater and a kiss coater.

In the present invention, any one of the base sheet, the adhesive layer, the strong adhesive layer, and the resin film, or two or more of them may contain an ultraviolet absorber. Examples of the ultraviolet absorber include benzophenone-based ultraviolet absorbers such as 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, and 2,2′-dihydroxy-4-methoxybenzophenone, phenyl salicylate, p- salicylic acid-based ultraviolet absorbers such as tert-butylphenyl salicylate and p-octylphenyl salicylate, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole,
-(2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-
Benzotriazole ultraviolet absorbers such as 3 ', 5'-di-tert-butylphenyl) benzotriazole;
Examples include cyanoacrylate-based ultraviolet absorbers such as 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate and ethyl-2-cyano-3,3'-diphenylacrylate. The content of the ultraviolet absorber is preferably in the range of 0.2 to 5 parts by weight based on 100 parts by weight of the material constituting each layer. The antenna sheet of the present invention can be attached to various places such as a glass window of an automobile.
The surface of the antenna sheet may be covered with a protection film. The protection film is used after the antenna sheet is manufactured and before the user attaches it to the adherend.
It is used to protect the surface from being contaminated, and is peeled off when the antenna sheet of the present invention is used as an antenna. Examples of the protect film include those described above as the base sheet and coated with a removable adhesive. The total thickness of the protection film is not particularly limited, but is usually 10 to 100 μm.
And it is preferably 20 to 60 μm.

[0019]

Next, the present invention will be described in detail with reference to examples. However, the present invention is not limited at all by these examples.

Example 1 A transparent plastic film as a substrate sheet 1 (material: polyethylene terephthalate resin, thickness: 125 μm)
m), 90 parts by weight of a conductive paste (component: particles of a conductive substance (silver particles, average particle size: 5 to 7 μm), 10 parts by weight of a binder (polyester resin), solvent (2-butoxyethyl acetate) 20 parts by weight were printed on the antenna-shaped pattern shown in FIG. 3 by a screen printer, and the antenna element 2 (thickness after drying: 10 μm, specific resistance: 2.
8 × 10 ⁻⁵ Ωm), and the terminal portion 3 was formed at the end. Next, a resist ink (component: a mixture of urethane acrylate and epoxy acrylate) is applied on the antenna element 2 with a width (pattern width + 1 to 2 mm) larger than the line width for the purpose of waterproofing and insulation. Except that the protective layer 5 (thickness: 15 μm) is formed, and the surface of the base sheet on which the antenna element and the terminal section are formed is covered with a protective film 9 (material: a polypropylene-based film coated with a rubber-based removable adhesive). Finished, total thickness: 40μ
m) to prepare a base sheet with an antenna element.

On the other hand, on one side of a transparent plastic film (material: polyethylene terephthalate resin, thickness: 25 μm) as the resin sheet 7, 100 parts by weight of a polyether-based urethane resin solution (manufactured by Dainichi Seika Kogyo Co., Ltd.)
8 parts by weight of an isocyanate-based crosslinking agent (manufactured by Dainichi Seika Kogyo Co., Ltd.), 3 parts by weight of a crosslinking accelerator (manufactured by Dainichi Seika Kogyo Co., Ltd.)
Further, a solution of a urethane elastomer in which 100 parts by weight of ethyl acetate was mixed was applied using a knife coater, and after application, the coating was cured and dried at 100 ° C. for 1 minute, and the adhesive layer 4 (thickness after drying: 10 μm, adhesive strength: 0.15N / 25mm,
100% modulus: 2.5 × 10 ⁶ N / m ² , breaking strength: 4 × 10 ⁷ N / m ² ).
A release sheet 8 (material: a polyethylene terephthalate resin layer coated on one side with an alkyd resin, thickness: 38 μm) was laminated thereon. Next, an adhesive (resin component: acrylic adhesive) and an ultraviolet absorber (2,2′-dihydroxy-4-methoxybenzophenone) are mixed on one surface of the resin sheet 7 on which the adhesive layer 4 is not formed. (Mixing ratio: 0.2 parts by weight of ultraviolet absorber with respect to 100 parts by weight of solids of the adhesive) The obtained adhesive composition is applied by a knife coater, and the acrylic strong adhesive layer 6 (thickness after drying) is applied. : 20 μm, adhesive strength: 10 N / 25 mm)
A laminated sheet having an adhesive layer and a strong adhesive layer was prepared.
One side of the base sheet with the antenna element, on which the antenna element 2 and the terminal portion 3 are not formed, and the strong adhesive layer surface of the laminated sheet except for the position of the terminal portion 3 are attached to each other,
An antenna sheet having the structure shown in FIG. 1 was prepared.

Example 2 In Example 1, the protection film coated on the surface of the base sheet with antenna elements on which the antenna elements 2 and the terminals 3 were formed was formed by forming the terminals of the base sheet. The base sheet with the antenna element is formed by coating the base sheet with the antenna element on the opposite side, not the side where the antenna element 2 and the terminal portion 3 are formed. An antenna sheet having the structure shown in FIG. 2 was prepared in the same manner as in Example 1 except that the surface of the strong adhesive layer of the sheet was bonded so as not to cover the terminal portion 3.

The antenna sheets prepared in the first and second embodiments are attached to the inside of the rear window of the passenger car,
Except for the diversity antenna kit part, a vehicle-mounted TV tuner and monitor (trade name: NVA9500F, manufactured by Clarion Co., Ltd.) were connected to the antenna sheets of Examples 1 and 2. In each case, TV radio waves (VHF
CH 1, 3, 4, 6, 8, 10, 12, UHF
CH 14, 16, 38), and the receiving state was excellent in both the first and second embodiments. These antenna sheets could be re-attached and re-peeled even if they were repeatedly applied and peeled to the window glass of a car more than 10 times, and the window glass as an adherend was not contaminated.

[0024]

According to the antenna sheet of the present invention, after being adhered to an adherend, easy peeling from the adherend and reattachment to the adherend can be easily repeated.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a part of an antenna sheet according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a part of an antenna sheet according to another embodiment of the present invention.

FIG. 3 is a plan view showing shapes of an antenna element and a terminal portion in the antenna sheet according to one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base sheet 2 Antenna element 3 Terminal part 4 Adhesive layer 5 Protective layer 6 Strong adhesive layer 7 Resin sheet 8 Release sheet 9 Protect film

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yasukazu Nakada 23-23 Honcho, Itabashi-ku, Tokyo Inside Lintec Co., Ltd. (72) Hiroshi Yamamoto 6-13-1 Shimbashi, Minato-ku, Tokyo Keiyo Engineering Co., Ltd. (72) Inventor Kenji Nishio 6-13-1 Shimbashi, Minato-ku, Tokyo Keiyo Engineering F-term (reference) 5J046 AA01 AA12 AB17 PA06 PA09 5J047 AA01 AA12 AB17 EC02

Claims (3)

[Claims] An antenna element made of a conductive material is formed on one side of a base sheet, and a terminal portion for connecting an antenna feeder is provided at one end of the antenna element. The surface of the base sheet on which the antenna element is formed is provided. Alternatively, an antenna sheet characterized in that an adhesive layer having removability and reattachability is formed on the opposite surface. 2. The adhesive layer has a 100% modulus of 6 × 10
⁶ N / ^{m 2} or less, an antenna sheet according to claim 1, wherein the breaking strength is ² × ¹⁰ 7 N / ^m 2 or more polyurethane elastomer layer. 3. The antenna sheet according to claim 1, wherein a strong adhesive layer and a resin sheet are laminated on a base sheet, and an adhesive layer is formed on a surface of the resin sheet.