JPH0592916U - Flat cable - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a flat cable that can be thinned without impairing sliding bending resistance and life. [Structure] The conductor 1 is embedded in a thermoplastic resin layer 12,
In the flat cable 15 in which the electrically insulating support layer 11 is laminated on the thermoplastic resin layer 12, the electrically insulating support layer 11 is formed of polyethylene naphthalate.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a flat cable preferably used for internal wiring of a communication device, a copying machine, a computer, an automobile and the like.

[0002]

[Prior Art]

 In a flat cable, which is also called a tape wire or a flat cable, a plurality of conductors 1 made of copper or the like are usually arranged and embedded in a thermoplastic resin layer 3 in parallel at a predetermined interval as shown in FIG. The thermoplastic resin layer 3 is held and fixed in this state, and the electrically insulating support layer 2 is laminated on both opposing sides of the thermoplastic resin layer 3 with an adhesive 4 interposed therebetween. In order to manufacture this flat cable, first, the composite film 5 as shown in FIG. 6, that is, the composite film 5 in which the electrically insulating support layer 2 is adhered onto the thermoplastic resin layer 3 by using the adhesive 4 is prepared. .. Next, the conductors 1 are arranged in a state of being separated from each other by a predetermined distance, and then the group of conductors 1 is sandwiched by the two composite films 5 so that the thermoplastic resin layers 3 face each other, and then this laminate is heated on a heating roll. The thermoplastic resin layer 3 is softened and integrated by thermocompression bonding using, for example, and a group of conductors 1 is embedded in the thermoplastic resin layer 3.

In the above-described conventional flat cable, the electrically insulating support layer 2 is formed of a film made of polyethylene terephthalate (hereinafter abbreviated as PET film). Since the PET film has excellent tensile strength and rigidity, the flat cable obtained by using the PET film can be provided with rigidity, and the sliding bending resistance of the cable can be improved.

[0004]

[Problems to be solved by the device]

 However, in order to cope with the recent demand for thinner flat cables, if the PET film forming the electrically insulating support layer 2 is made thin, the resulting flat cable will be significantly impaired in sliding bending resistance. Then, there was a problem that the life was extremely shortened.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a flat cable that can be made thin without impairing the sliding bending resistance.

[0006]

[Means for Solving the Problems]

 In the flat cable of the present invention, the above object is achieved by using a film made of polyethylene naphthalate as the electrically insulating support layer. As the material forming the thermoplastic resin layer of the flat cable of the present invention, various conventionally known thermoplastic resins can be used. Among them, the thermoplastic polyester resin and the thermo-crosslinking polyester resin in which a crosslinking agent is added are used. Resins and vinyl chloride resins are preferred.

[0007]

[Action]

 Since polyethylene naphthalate has a molecular structure similar to that of polyethylene terephthalate, its basic characteristics are almost the same, but the use of polyethylene naphthalate film increases the rigidity of the flat cable and improves the sliding and bending resistance. You can

[0008]

【Example】

 An embodiment of the flat cable of the present invention will be described below with reference to the drawings. (Example) FIG. 1 shows a flat cable of this example. This flat cable 15 is one in which four rectangular thin conductors 1 (thickness 100 μm) are embedded in a thermoplastic resin layer 12 made of a thermoplastic polyester adhesive at predetermined intervals. An electrically insulating support layer 11 made of a polyethylene naphthalate film having a thickness of 25 μm is provided on both front and back surfaces of the thermoplastic resin layer 12 via a primer layer 13 having a thickness of 3 μm.

The flat cable 15 is manufactured as follows. First, as shown in FIG. 2, a polyethylene naphthalate film 11 having a thickness of 25 μm and a thermoplastic resin layer 12 having a thickness of 50 μm made of a thermoplastic polyester adhesive are bonded and integrated via a primer layer 13 to form a composite. A film 14 was obtained. Next, as shown in FIG. 3, four conductors 1 were arranged at a predetermined interval, and two composite films 14 were arranged so as to sandwich the conductors 1 therebetween. At this time, the two composite films 14 were arranged so as to face each other so that the thermoplastic resin layer 12 of each composite film 14 was in contact with the conductor 1. Then, this was heated and pressure-bonded using a heating roll at 170 ° C. to obtain the flat cable 15.

(Comparative Example) A flat cable different from that of the example was prepared only in that a 25 μm-thick PET film was used in place of the polyethylene naphthalate film to form the electrically insulating support layer 11. The flat cable of the comparative example was used.

(Prior art example) A flat cable different from that of the example is prepared only in that a PET film having a thickness of 50 μm is used instead of the polyethylene naphthalate film to form the electrically insulating support layer 11. The flat cable of the conventional example is used.

The flat cables of the above-mentioned Examples, Comparative Examples and Conventional Examples were subjected to the following sliding bending resistance test. (Sliding Bending Resistance Test) As shown in FIG. 4, the flat cable 15 is bent into a U shape having a radius of 15 mm, the A end is fixed, and the B end is moved up and down by 50 mm at a speed of 100 reciprocations / min. The number of reciprocations until the conductor 1 was broken was measured. The results are shown in Table 1.

[0013]

[Table 1] Note 1 In terms of sliding flexibility, 10 million cycles or more means cutting after 10 million cycles because it does not cut after 10 million cycles.

From the results shown in Table 1, the flat cable 15 of the example in which the electrically insulating support layer 11 is formed of the polyethylene naphthalate film having a thickness of 25 μm has the electrically insulating support layer formed of the PET film having a thickness of 50 μm. It can be seen that the formed flat cable has a sliding bending resistance comparable to that of the conventional flat cable. On the other hand, it can be seen that the flat cable of the comparative example in which the electrically insulating support layer is formed of a PET film having a thickness of 25 μm has extremely poor sliding bending resistance. In addition, looking at the column of flat cable thickness in Table 1, it can be seen that the flat cable 15 of the example is about 20% thinner than the flat cable of the conventional example.

[0015]

[Effect of the device]

 As described above, in the flat cable of the present invention, since the electrically insulating support layer is formed of the polyethylene naphthalate film, it has sufficient rigidity and good sliding bending resistance even if the support layer is thin. Will be things. Therefore, according to the flat cable of the present invention, it is possible to meet the demand for thinning of the flat cable, which is required today, while avoiding the deterioration of the life of the flat cable.

[Brief description of drawings]

FIG. 1 is a sectional view showing a flat cable of an embodiment.

FIG. 2 is a cross-sectional view showing a composite film used in manufacturing the flat cable of the example.

FIG. 3 is a cross-sectional view showing one step in manufacturing the flat cable of the embodiment.

FIG. 4 is a schematic diagram for explaining a method of a slide cable flex resistance test of a flat cable.

FIG. 5 is a cross-sectional view showing a conventional flat cable.

FIG. 6 is a cross-sectional view showing a composite film used in manufacturing the conventional flat cable.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 conductor 2 electric insulating support layer 3 thermoplastic resin layer 4 adhesive layer 5 composite film 11 electric insulating support layer 12 thermoplastic resin layer 14 composite film 15 flat cable

Claims (1)

[Scope of utility model registration request] 1. A plurality of conductors are arranged and embedded in parallel in a thermoplastic resin layer at a predetermined interval, and an electrically insulating support layer is laminated and integrated on both opposing sides of the thermoplastic resin layer. A flat cable, wherein the electrically insulating support layer is formed of a polyethylene naphthalate film.