JP2002329425A - Shielding material for flat cable and flat cable with shield - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shielding material for a flat cable, which is easy to be mounted on the flat cable and superior in performances such as an electromagnetic wave shieldability, slidability, flame retaudancy or the like and economic property, and provide the flat cable with a shield to use the material, superior in performances and economic property. SOLUTION: The shielding material 10 for the flat cable is constituted so that a metallic thin film layer 2 such as an aluminum vapor-deposited layer or the like is installed at one face of an insulating substrate 1 such as a PET film or the like, and electroconductive heat-adhesive layer 3 containig an electroconductive filler in heat-adhesive resin is installed on it, and a flame- resistant layer 4 containing flame resistance additive in heat-adhesive resin is installed further on it so that the area ratio will be 50 to 95% uniformly at the entire surface in a pattern state. Further, the flat cables is prepared by coiling the shielding material 10 to an outer periphery of the flat cable with the electroconductive heat-adhesive layer 4 toward the inside and by heating and pressurizing the material to be adhered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat cable shielding material (electromagnetic wave shielding film) and a flat cable having a shielding function using the same.
By improving the layer structure of the shield material such as the shield layer and adhesive layer, it is possible to easily conduct the shield layer and the ground wire, and it is excellent in shielding properties, slidability, flame retardancy, economy, The present invention also relates to a flat cable shield material excellent in workability in attaching to a flat cable and a flat cable with a shield function using the same.

[0002]

2. Description of the Related Art In recent years, flat cables have been used in place of horizontal wound shield wires or coaxial wires for signal transmission in interfaces between devices such as communication devices, computers and peripheral devices and between devices. However, in an environment where various radio waves, electromagnetic waves, and the like are generated as in today, the flat cable is affected by these factors and often causes malfunction of the computer.

Accordingly, various shield technologies have been developed for protecting the flat cable from electromagnetic waves and for shielding electromagnetic waves generated from the flat cable from affecting other devices. For example, a metal foil is used in which an insulating adhesive layer is provided on the surface of a metal foil in order to adhere the metal foil to a flat cable by using a metal foil for a shield layer of the shield material. Further, a shield material in which an adhesive containing a conductive substance such as metal powder is applied to a plastic film and the conductive adhesive layer is used as a shield layer has been studied (JP-A-6-283).
053).

Further, in order to improve the slidability of the shielding material, an electromagnetic wave shielding film in which a metal thin film is formed on a base film and then an adhesive resin layer containing silver particles and / or copper particles is formed has been proposed. (Japanese Unexamined Patent Application Publication No. 7-
94036). This shield tape has excellent conductivity because it has a metal thin film, has good electromagnetic wave shielding properties, and has good slidability. However, when a flame-retardant engineering plastic film is used for the base film, the cost is high, and the polyester film When used, there was a problem that the flame retardancy was poor.

[0005] Further, there has been proposed an electromagnetic wave shielding film in which a flame-retardant engineering plastic film is used as a base film, a silver thin film is formed as a metal thin film on the base film, and a nickel filler is contained in an adhesive resin layer (Japanese Patent Application Laid-Open No. H11-157556). Kaihei 11-120831). This shield tape is also expensive because the base film is a flame-retardant engineering plastic film and the metal thin film is silver deposited.

[0006]

However, a metal foil is used for the shielding layer of the shielding material, and an insulating adhesive layer is provided on the surface of the metal foil in order to adhere the metal foil to a flat cable. In order to conduct the shield layer and the ground wire of the flat cable, a part of the insulating adhesive layer is cut off to expose the metal foil, and a part of the covering material of the flat cable is cut And expose
The exposed ground line and the metal foil (shield layer) had to be conducted by a special processing method such as spot welding. When metal foil is used for the shield layer,
Although excellent in shielding properties, metal foil is inferior in flexibility,
There is a problem in that the mounting of the flat cable is restricted and the shape of the electronic member is restricted.

[0007] In order to solve the above-mentioned problems, a shielding material provided with a conductive adhesive layer on a plastic film has a high flexibility, so that a restriction is imposed on mounting of a flat cable and a shape of an electronic member is restricted. However, there is a problem that the shielding characteristics are inferior to the shielding material using a metal foil. Furthermore, in order to make the shielding material flame-retardant, when using a flame-retardant engineering plastic film such as polyphenylene sulfide, polyamide imide, polyether imide, or polyarylate as the base film, the cost of these films is high. However, the cost of the shielding material is increased, and there is a problem in terms of economy.

The present invention has been made in order to solve such a problem, and an object of the present invention is to provide a workability in attaching to a flat cable to provide an electromagnetic wave shielding property. We provide flat cable shielding materials that have the necessary sliding characteristics, electromagnetic wave shielding properties, flame retardancy, thermal adhesion, and are economical, and also provide the necessary materials manufactured using the shielding materials. An object of the present invention is to provide a flat cable with a shield function that is excellent in performance and economical efficiency with high productivity.

[0009]

The above objects can be attained by the present invention described below. That is, according to the first aspect of the present invention, a metal thin film layer is provided as a shield layer on one surface of a flexible insulating substrate, and a conductive film is formed on the metal thin film layer by applying a heat-adhesive resin. A conductive heat-adhesive layer containing a conductive filler is provided, and further, on the conductive heat-adhesive layer, a flame-retardant heat-adhesive layer containing a flame-retardant imparting agent in a heat-adhesive resin is provided. And a shield material for a flat cable, which is provided in a pattern at an area ratio of 50 to 95% of the total surface area of the conductive heat bonding layer.

In the above description, the pattern of the flame-retardant heat bonding layer may be any pattern such as a stripe pattern or a pattern in which spot-shaped patterns such as circles and rectangles are arranged in a dispersed manner. It is preferable that they are provided uniformly.

By adopting such a configuration, the following functions and effects can be obtained. (1) Since a metal thin film layer is provided as a shielding layer (electromagnetic wave shielding layer) instead of a metal foil, the shielding material can have good shielding properties and excellent flexibility. Therefore, the flat cable to which this is attached can be made excellent in shielding properties and sliding characteristics without any restrictions on its installation and no restriction on the shape of the electronic member. (2) A conductive heat bonding layer is provided on the metal thin film layer as a shield layer, and the flame-retardant heat bonding layer is further provided thereon with 50 to 95% of the total surface area of the conductive heat bonding layer. Because it is provided uniformly over the entire surface in a pattern with an area ratio of 、, the area ratio of the flame-retardant thermal adhesive layer is high, and a flexible insulating base material is used for high-cost flame-retardant engineering plastic film. In addition, even if a general-purpose plastic film such as a biaxially stretched polyester film is used, sufficient flame retardancy can be imparted to the shield material, and the cost can be reduced.

(3) Further, since the lower conductive heat bonding layer is uniformly exposed on the entire surface between the patterned flame-retardant heat bonding layers, the entire surface has a heat bonding property. The shield material can be easily attached to the flat cable by thermocompression bonding. At this time, only a part of the ground cable of the flat cable is exposed, and conduction between the ground wire and the metal thin film layer (shield layer) is achieved. Can be easily performed by the conductive heat bonding layer. If the area ratio of the flame-retardant heat-bonding layer is less than 50%, the flame-retardancy of the shielding material becomes insufficient, and if it exceeds 95%, the exposed area of the conductive heat-bonding layer becomes small. It is not preferable because it becomes too small and it becomes difficult to conduct the ground line and the metal thin film layer (shield layer).

According to a second aspect of the present invention, the flexible insulating substrate is a biaxially stretched polyethylene terephthalate film, and the metal thin film layer has a thickness of 0.04 to 0.04.
2. The flat cable shielding material according to claim 1, which is a 0.2 μm aluminum vapor-deposited layer.

By adopting such a configuration, in addition to the functions and effects of the invention described in the first aspect, the biaxially stretched polyethylene terephthalate film (hereinafter referred to as a PET film) has flexibility and insulating properties. Besides, heat resistance,
The overall performance is excellent and the cost is low, such as mechanical strength, water resistance, and chemical resistance. Therefore, the cost can be reduced while maintaining the required performance of the shielding material. Further, by forming the metal thin film layer of the shield layer as an aluminum vapor-deposited layer having a thickness of 0.04 to 0.2 μm, the shield has a flexible and sufficient shielding effect, and is excellent in productivity and economy. It can be a layer. The thickness of the aluminum vapor-deposited layer is preferably in the range of 0.04 to 0.2 μm,
The range of 0.09 to 0.12 μm is more preferable. When the thickness is less than 0.04 μm, the shielding effect becomes insufficient, and when the thickness exceeds 0.2 μm, the layer has sufficient shielding properties. It is not preferable because the productivity is lowered due to the necessity of processing and the production cost is increased.

According to a third aspect of the present invention, there is provided the flat cable shielding material according to the first or second aspect, wherein the conductive thermal bonding layer further contains a flame retardant.

As described above, the conductive heat-bonding layer is
It is provided to conduct the metal thin film layer (shield layer) to the ground line of the flat cable, and does not require a high degree of conductivity, and can reduce the content of the conductive filler. Therefore, in the conductive heat bonding layer,
The required thermal adhesiveness can be maintained even when a flame retardant is added together with the conductive filler. Therefore, by adopting such a configuration, in addition to the functions and effects of the invention described in claim 1 or 2, it is possible to further improve the flame retardancy of the shielding material without impairing the thermal adhesion to the flat cable. In addition, by manufacturing a flat cable using this shield material, it becomes easy to pass the flat cable through a UL standard flame retardancy test.

According to a fourth aspect of the present invention, the flat cable shielding material according to any one of the first to third aspects is integrated with the outer periphery of the flat cable by heating and pressurizing, thereby imparting a shielding function to the flat cable. It is a flat cable with a shield characterized by the above-mentioned.

By adopting such a structure, the performance and the effect of the shield material for a flat cable according to any one of claims 1 to 3 are added to the flat cable. It is possible to economically provide a shielded flat cable having excellent performance and productivity such as sliding characteristics and flame retardancy.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic sectional view showing the configuration of an embodiment of the flat cable shielding material of the present invention. FIG. 2 is a diagram illustrating the configuration of an embodiment of a shielded flat cable manufactured using the flat cable shielding material of the present invention,
(A) is a partially cutaway plan view, (B) is A in (A).
It is an expanded sectional view in the -A line.

The shield material for a flat cable of the present invention can be configured as shown in FIG. That is, the shield material 10 for a flat cable shown in FIG.
On one surface of a flexible insulating base material 1 such as a T film, a metal thin film layer 2 such as an aluminum vapor-deposited layer is provided as a shield layer. A conductive heat-bonding layer 3 containing a conductive filler is provided, and a flame-retardant heat-bonding layer 4 containing a flame-retardant-imparting agent in a heat-bonding resin is further provided thereon. The adhesive layer 3 is provided so as to be uniformly provided in a pattern so as to have an area ratio of 50 to 95% of the total surface area of the adhesive layer 3. Therefore, between the patterned flame-retardant heat-bonding layers 4, the lower conductive heat-bonding layer 3 is uniformly exposed at an area ratio of 50 to 5%. Although not shown in the drawings, a primer layer or the like can be provided in advance on the surface of the flexible insulating base material 1 on which the metal thin film layer 2 is formed to improve the adhesiveness. .

When a flat cable with a shield is manufactured using the flat cable shield material 10, it can be configured, for example, as shown in FIGS. That is, in the shielded flat cable 100 shown in FIG. 2, the conductor 5 and the ground wire 6 made of tin-plated soft copper foil or the like are arranged in parallel at a predetermined interval, and are covered with the flat cable covering 7 from both sides. Heating and pressurizing to embed the conductor 5 and the ground wire 6 to integrate them, and produce a flat cable,
A part or all of the covering material 7 on one side of the ground line 6 of the flat cable is cut off in the length direction to expose the ground line 6, and the outer periphery thereof is protected by the flat cable shielding material 10 with the difficulties. The heat-bonding layer 4 is formed so that the surface on which the heat-resistant heat-bonding layer 4 is formed faces inward, and both ends are overlapped.

By adopting such a configuration, the exposed portion of the ground wire 6 and the metal thin film layer (shield layer) 2 of the flat cable shield material 10 are heated and pressed only by the flame-retardant heat bonding layer. 4. Conductive thermal adhesive layer 3 exposed between
Through the ground line-shield layer conducting portion 8, the flat cable is provided with excellent shielding properties by the metal thin film layer 2, and performance and economy such as slidability and flame retardancy are improved. An excellent shielded flat cable 100 can be provided with high productivity. FIG.
Then, as an example of a shielded flat cable,
In order to further complete the shielding effect, the flat cable shielding material 10
Although the configuration in which the flat cable is attached is shown, for example, a configuration in which the flat cable shield material is attached only to the surface of the flat cable on the side where the ground wire is exposed may be used depending on the usage mode and the like.

In the flat cable shielding material 10 of the present invention shown in FIG.
Has excellent properties such as flexibility, electrical insulation, heat resistance, various mechanical strength, chemical resistance, solvent resistance, etc.
It is preferably low cost, for example, polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polytetramethylene terephthalate, polyolefins such as polypropylene, ethylene-propylene copolymer, nylon 1
2, non-stretched or stretched films such as polyamides such as nylon 6, nylon 66, wholly aromatic polyamides, and fluorine-containing resins such as polytrifluoroethylene, polyvinylidene fluoride, and polyvinyl fluoride can be used. Among them, a PET film is excellent in ease of film formation and economical efficiency as well as the above-mentioned performance, and can be particularly preferably used. The thickness of the flexible insulating substrate 1 is suitably in the range of 6 to 20 μm from the viewpoint of strength and flexibility. Further, it is preferable that the surface of the insulating base material 1 on which the metal thin film layer 2 is formed is subjected to an adhesion enhancing treatment such as a corona discharge treatment, a plasma treatment and an ozone treatment.

Next, the metal thin film layer (shield layer) 2 provided on one surface of the flexible insulating base material 1 is preferably one having high conductivity when a thin film is formed.
A vapor-deposited layer of aluminum, silver, copper, nickel or the like is suitable, and among them, an aluminum-deposited layer is particularly preferable because it is excellent in processability and conductivity of vapor deposition, and is low in cost and excellent in economic efficiency.

The shielding property of the metal thin film layer 2 increases as the thickness thereof increases. However, when the metal thin film layer 2 is too thick, the flexibility is reduced and the bending suitability and slidability deteriorate. Accordingly, as described above, the thickness of the metal thin film layer 2 is suitably from 0.04 to 0.2 μm, and more preferably from 0.09 to 0.12 μm. The method for forming the metal thin film layer 2 includes vacuum deposition, sputtering,
A CVD method or the like can be used, but a vacuum evaporation method excellent in mass productivity is advantageous.

Next, the conductive heat bonding layer 3 provided on the metal thin film layer 2 and the flame-retardant heat bonding layer 4 further provided thereon in a pattern are formed by adding a conductive filler or It is formed of a resin layer containing a flame retardant.
The heat-adhesive resin used for the conductive heat-adhesive layer 3 and the flame-retardant heat-adhesive layer 4 satisfactorily adheres to the respective lower layers, that is, the metal thin film layer 2 or the conductive heat-adhesive layer 3 and is flat. It is necessary to thermally bond the outer layer of the cable covering material and the exposed ground wire, and a common thermal adhesive resin can be used.

Examples of such a heat-adhesive resin include polyester resins, polyolefin resins (including ionomers and other acid-modified polyolefin resins), polyvinyl acetate resins, polystyrene resins, acrylic resins, and the like. Polyamide resins and the like can be mentioned, and one kind can be selected from these or two or more kinds can be used in combination. In particular, a polyester film is often used for the outer layer of the covering material of the flat cable, and in that case, a polyester-based resin can be suitably used as the heat-adhesive resin. This polyester resin is a saturated copolymerized polyester resin, and among them, a resin composition containing a resin having a glass transition point of −50 to 80 ° C. and a weight average molecular weight of 7000 to 50,000 as a main component is preferable. It is.

Next, in the conductive heat bonding layer 3, as the conductive filler to be contained in the heat bonding resin, for example, metal powder such as silver, nickel, copper and aluminum, alloy powder such as solder, metal whisker Alternatively, metal-plated glass fiber powder, carbon particles, or the like can be used. The particle size or length of such a conductive filler is preferably in the range of 0.01 to 15 μm, and more preferably in the range of 0.01 to 5 μm in which dispersion is easy.

In the flame-retardant heat-bonding layer 4, examples of the flame-retardant imparting agent to be contained in the heat-adhesive resin include chlorinated paraffin, chlorinated polyethylene, chlorinated polyphenyl and perchlor pentacyclodecane. Chlorinated compounds such as acetic acid, heptic anhydride, chlorendic acid, and tetrabromoethane, tetrabromobisphenol A, hexabromobenzene, decabromobiphenyl ether, tetrabromophthalic anhydride, polydibromophenylene oxide, hexabromocyclodecane, and bromide Organic or inorganic compounds containing a halogen element, such as bromine-based compounds such as ammonium; and triallyl phosphate, alkyl allyl phosphate, alkyl phosphate, dimethylphosphonate, phosphorinate, halogenated phosphorinate Ether, trimethyl phosphate,
Tributyl phosphate, trioctyl phosphate,
Tributoxyethyl phosphate, octyl diphenyl phosphate, tricresyl phosphate, cresyl phenyl phosphate, triphenyl phosphate, tris (chloroethyl) phosphate, tris (2-chloropropyl) phosphate, tris (2,3-dichloropropyl) phosphate, tris (2,3-dibromopropyl) phosphate, bis (2,3-dibromopropyl) 2,3-dichloropropyl phosphate, bis (chloropropyl) monooctyl phosphate, polyphosphonate, polyphosphate, aromatic polyphosphate, dibromo Phosphoric acid esters or phosphorus compounds such as neobentyl glycol, phosphonate type polyols,
Phosphate type polyols, polyol compounds such as halogen-containing polyols, aluminum hydroxide, magnesium hydroxide, antimony trioxide, antimony trichloride, antimony pentoxide, zinc borate, antimony borate, boric acid, antimony molybdate, molybdenum oxide, Rin·
Metal powders and inorganic compounds such as nitrogen compounds, calcium aluminum silicates, zirconium compounds, tin compounds, dawsonite, calcium aluminate hydrate, copper oxide, metal copper powder, calcium carbonate, barium metaborate, and others, silicone polymers, Ferrocene, fumaric acid, maleic acid, triazine compounds, melamine cyanurate, isocyanurate, urea, guanidine compounds and the like can be mentioned. One of these can be selected, or two or more can be used in combination.

The method of forming the conductive heat-bonding layer 3 and the flame-retardant heat-bonding layer 4 formed by adding a conductive filler or a flame retardant to the above-mentioned heat-bonding resin is described in the following. In the case of the conductive heat-bonding layer 3, it is applied on a whole surface of the metal thin film layer 2 by a coating means such as a knife coat, a roll coat, a bar coat, a micro bar coat, a gravure coat, and dried. Can be formed. Further, in the case of the flame-retardant heat bonding layer 4, since it is provided on the conductive heat bonding layer 3 in a pattern such that the area ratio is 50 to 95%, means such as screen printing, gravure printing, etc. To form a pattern by applying and drying.

In the preparation of the above-mentioned coating liquid, in the case of a coating liquid for a conductive heat-adhesive layer, the above-mentioned conductive filler is added to one or more kinds of solutions of the above-mentioned heat-adhesive resin, and if necessary, , Dispersant, viscosity modifier, and other additives,
It can be manufactured by mixing, dispersing or dissolving. The content of the conductive filler varies depending on the material, shape and the like of the conductive filler to be used, but cannot be said uniformly. However, the content of the solid content of the conductive heat bonding layer 3 is preferably in the range of 10 to 60% by weight, When a filler is used, the content is preferably 30 to 60% by weight. In addition, the conductive heat bonding layer 3 may contain a flame retardant in addition to the conductive filler.
In this case, the conductive filler and the flame retardant are added to the coating liquid for the conductive heat bonding layer in a range that does not impair the heat bonding property, usually with respect to the solid content of the conductive heat bonding layer 3. Can be added in a total amount of up to 80% by weight.

In the case of a coating solution for a flame-retardant heat-adhesive layer, one or two or more solutions of the heat-adhesive resin may be used.
It can be prepared by adding one or more of the above-mentioned flame retardants, and further adding, if necessary, a dispersant, a viscosity modifier and other additives, and mixing, dispersing or dissolving. The content of the flame retardant is preferably in the range of 20 to 80% by weight of the solid content of the flame-retardant heat bonding layer 3. The solution of the heat-adhesive resin is usually a solution using an organic solvent, but may be an aqueous or water-alcohol-based emulsion or dispersion depending on the type of the heat-adhesive resin.

The thicknesses of the conductive heat-bonding layer 3 and the flame-retardant heat-bonding layer 4 are 10 to 50 in terms of the thickness when dried.
μm is preferable, and 15 to 30 μm is more preferable. By configuring the conductive thermal bonding layer 3 and the flame-retardant thermal bonding layer 4 in this manner, a sufficient amount of the flame retardancy-imparting agent can be contained in the flat cable shield material 10.
Even when a PET film or the like is used for the insulating substrate 1 having flexibility, the shielding member 10 has an oxygen index (JIS).
K7201-2), a flame retardancy of 21 or more, for example, a flame retardancy of 25 to 35 in oxygen index can be easily imparted.
Further, by manufacturing a shielded flat cable using the shield material 10, the flat cable can pass a UL standard flame retardancy test.

Further, regarding the conductivity of the conductive thermal bonding layer 3, the surface resistivity 1 required for conduction between the metal thin film layer 2 of the shielding material 10 and the exposed ground line of the flat cable is also set.
0 Ω / □ or less can be easily applied to the conductive heat bonding layer 3. Therefore, the flat cable shield material 10 is easily exposed by covering the outer periphery of the flat cable with the surface on which the flame-retardant heat-bonding layer 4 is formed facing inward, and heating and pressurizing from the outside. The ground wire and the metal thin film layer 2 of the shield material 10 are conducted by the conductive heat bonding layer 3 exposed between the pattern-shaped flame-retardant heat bonding layers 4, thereby giving the flat cable excellent shielding properties. can do.

[0035]

The present invention will be described more specifically below with reference to examples. However, unless the present invention exceeds the gist,
It is not limited to the embodiment. Example 1 A flat cable shielding material 10 having the structure shown in FIG. 1 was produced, and a 12 μm-thick PET film (one-sided corona discharge treatment) was used for a flexible insulating base material 1. An aluminum vapor-deposited layer having a thickness of 0.1 μm is formed as a metal thin film layer (shield layer) 2 on the corona-discharge treated surface, and a conductive thermal adhesive layer having the following composition is formed on the entire surface of the aluminum vapor-deposited layer. The coating liquid is applied by a microbar coating method so as to have a thickness of 30 μm when dried, and dried to form a conductive heat-bonding layer 3, and further thereon, a flame-retardant heat-bonding layer having the following composition The coating liquid for use was screen-printed using a pattern plate in which diagonal 7-mm-wide stripes were arranged in parallel at 3 mm intervals so that the thickness when dried was 30 μm. Apply and dry To form a flame-retardant heat-bonding layer 4 to produce a shielding member 10 for flat cable of Example 1 Te.

(Composition of Coating Solution for Conductive Thermal Adhesive Layer) Thermal adhesive resin (saturated copolymerized polyester resin) 40 parts by weight Conductive filler (silver powder, major axis 1 to 3 μm) 30 parts by weight Flame retardant bromine Flame retardant 20 parts by weight Antimony trioxide 5 parts by weight Aluminum hydroxide 5 parts by weight Solvent (MEK: toluene 1: 1 by weight) 180 parts by weight (Note) MEK is methyl ethyl ketone

(Composition of Coating Solution for Flame-Retardant Thermal Adhesive Layer) Thermal adhesive resin (saturated copolymerized polyester resin) 50 parts by weight Flame retardant agent Bromine-based flame retardant 30 parts by weight Antimony trioxide 10 parts by weight Water Aluminum oxide 10 parts by weight Solvent (MEK: toluene weight ratio 1: 1) 180 parts by weight

The flame retardancy of the flat cable shield material 10 produced as described above was 31 in oxygen index.
The surface specific resistance of the conductive heat bonding layer 4 was 5Ω / □. Next, the flat cable shielding material 10
Was used to produce a shielded flat cable 100 having the configuration shown in FIGS. 2A and 2B as follows. That is, as a flat cable, the thickness is 0.0
A plurality of conductors 5 made of flat tinned annealed copper foil having a width of 5 mm and a width of 0.8 mm are arranged in parallel at a pitch between conductors of 1.0 mm, covered with a flat cable covering material 7 from both sides, and heated with a heating rubber roll. Using a flat cable produced by embedding and integrating the conductor 5 by applying pressure, the covering material 7 on one side of the conductor 5 at one end of the flat cable is continuously cut off in the length direction to expose the conductor, and the ground wire is formed. After that, the outer periphery of the flat cable is turned by the flat cable shield material 10 so that the surface on which the flame-retardant heat-bonding layer 4 is formed faces inward, and both ends are overlapped. The flat cable 100 with the shield was manufactured by heating, pressurizing, thermally bonding, and integrating.

In the shielded flat cable 100 thus manufactured, the exposed portion of the ground wire 6 and the metal thin film layer (shield layer) 2 of the flat cable shield material 10 are electrically conductively bonded by heating and pressing. Through the layer 3, it was easily conducted at the ground line-shield layer conduction portion 8, and excellent flatness was imparted to the flat cable and sliding characteristics were also excellent. Further, regarding the flame retardancy, it passed the UL standard flame retardancy test.

[0040]

As described above in detail, according to the present invention, there is provided a flat cable shielding material for imparting electromagnetic wave shielding to a flat cable, which has excellent flame retardancy and electromagnetic wave shielding. In addition to having sliding properties (bending resistance), it has excellent heat adhesion to the covering material of the flat cable and conductive heat adhesion to the ground wire (metal), and is easy to attach to the flat cable. Further, there is an effect that a shield material for a flat cable which is excellent in economy can be provided with high productivity. Also, by using the flat cable shielding material of the present invention,
By manufacturing shielded flat cables,
The present invention has the effect of providing a shielded flat cable having excellent flame retardancy and electromagnetic wave shielding properties, and excellent performance such as sliding characteristics (bending resistance) with good productivity and economy.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a configuration of an embodiment of a flat cable shielding material of the present invention.

FIG. 2 is a view for explaining the configuration of an embodiment of a shielded flat cable manufactured using the flat cable shielding material of the present invention, wherein (a) is a partially cutaway plan view, and (b). FIG. 2 is an enlarged cross-sectional view taken along line AA in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulating base material which has flexibility 2 Metal thin film layer (shield layer) 3 Conductive thermal bonding layer 4 Flame retardant thermal bonding layer 5 Conductor 6 Ground wire 7 Flat cable covering material 8 Ground wire-shield layer conduction part 10 Shield material for flat cable 100 Flat cable with shield

Continued on the front page F-term (reference) 5G311 CB01 CD03 CE01 5G313 AA10 AB05 AC06 AD02 AE01 AE08

Claims (4)

[Claims] 1. One surface of a flexible insulating base material,
A metal thin film layer is provided as a shield layer, and a conductive heat bonding layer formed by adding a conductive filler to a heat bonding resin is provided on the metal thin film layer. A flame-retardant heat-adhesive layer comprising a heat-adhesive resin containing a flame-retardant agent is provided in a pattern at an area ratio of 50 to 95% of the total surface area of the conductive heat-adhesive layer. Shielding material for flat cables, characterized in that: 2. The flexible insulating base material is a biaxially stretched polyethylene terephthalate film, and the metal thin film layer is a 0.04 to 0.2 μm thick aluminum vapor-deposited layer. The shield material for a flat cable according to claim 1. 3. The flat cable shielding material according to claim 1, wherein the conductive thermal adhesive layer further contains a flame retardant. 4. A flat cable having a shielding function, wherein the flat cable shielding material according to any one of claims 1 to 3 is integrated by heating and pressurizing the flat cable with an outer periphery thereof. Flat cable.