JPH0538486Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention relates to a flat cable, particularly a flat cable that passes the flame retardant test of the UL standard. [Prior Art] In the United States, when a flat cable is used as a wiring material for electronic equipment, it must pass the VW-1 flame retardant test of the UL standard flame retardant test. In this test, a burner flame was applied to a test piece held vertically for 15 seconds, the flame was removed, and after the test piece had extinguished, the burner flame was applied again for 15 seconds.The test was repeated five times in total. Anti-inflammatory time is 60
If it is within seconds, it is considered a pass. A conventional flat cable will be explained with reference to FIGS. 1 and 2. Above and below a large number of wires No. 1 to No. 10 arranged in a plane, from the outermost layer, a flame retardant polyvinyl chloride film 5, a polyester tape 6, an aluminum tape 7, a thermoplastic resin sprite coat adhesive layer 8, and A flat cable is known which is provided with a laminated tape consisting of a polyester tape 9 and a thermoplastic resin solid coat adhesive layer 10. [Problems that the invention aims to solve] As mentioned above, flat cables using conventional tape do not pass the flame retardant test of the UL standard. This is because the shrinkage force of the polyvinyl chloride film is greater than the adhesive force of the thermoplastic resin stripe coat adhesive layer, so the thermoplastic resin stripe coat adhesive layer and polyester tape peel off, causing the polyvinyl chloride film to "warp". As a result, the inner polyester tape and aluminum tape, which are adhesively integrated with the polyvinyl chloride film, simultaneously undergo a "warping" phenomenon. This is because the innermost flammable polyester tape will ignite. In order to pass this test, it is necessary to prevent the occurrence of the "warpage" phenomenon. This includes the flexibility temperature of the polyvinyl chloride film.
It is possible to keep the shrinkage force below a certain level at temperatures above 80℃, but there are currently many manufacturing problems in mass-producing films with a thickness of 100 μm or less by increasing the softening temperature and keeping the shrinkage force below a certain level. accompanied by. The purpose of this invention is to provide a highly reliable, low-cost flat cable that passes the VW-1 flame retardant test of the UL standard. [Means for Solving the Problems] The present invention provides a flat cable in which a large number of insulated wires are arranged in a planar manner and integrated.
It has the characteristics of an oxygen index of 30 or more, a flexibility temperature of less than 80℃, a longitudinal elongation of 0 to -15%, a transverse elongation of 0 to +5%, and a thickness of 10 to +5%, which poses no problems in terms of manufacturing technology.
100μm flame retardant PVC film and thickness
A tape laminated with a 2.6-25 μm polyester tape, and below that a 5-25 μm thick aluminum tape with a thickness of 25-25 μm and flame retardant with an oxygen index of 28 or higher.
By providing a 100 μm polyester tape, this objective was achieved by providing a highly reliable flat cable with flame retardant properties throughout the cable. [Function] In the flat cable of the present invention, for example, a tin-plated annealed copper wire is coated with an insulator such as foamed polypropylene, a drain wire made of tin-plated annealed copper wire is placed vertically on the insulator, and an aluminum foil polyester is wrapped around the outer periphery of the drain wire. A flat cable is made by wrapping a laminated tape, arranging the wires in parallel at a certain pitch, then laminating various tapes from above and below, and fusing these together.The oxygen index increases from the outermost layer of the tape.
Flame-retardant polyvinyl chloride film with a thickness of 10-100μm, with a temperature of 30 or higher, a flexibility temperature of less than 80℃, a longitudinal elongation of 0 to -15%, and a transverse elongation of 0 to +5%. and a polyester tape with a thickness of 2.6 μm to 25 μm, and below that, an aluminum tape with a thickness of 5 to 25 μm and a flame retardant tape with an oxygen index of 28% or more and a thickness of 25 to 25 μm.
A tape made by laminating 100 μm polyester tape is provided. This makes it possible to obtain a flat cable that passes the VW-1 flame retardancy test, regardless of the degree of "warpage" of the polyvinyl chloride film in the outermost layer. [Example] Hereinafter, an example of the present invention will be described with reference to the drawings. Figure 1 is a structural explanatory diagram showing one embodiment of the flat cable of the present invention, in which figure a shows the arrangement of the core wires, figure b shows the upper tape, figure c shows the lower tape, and figure 1 shows the arrangement of the core wires. d shows an enlarged view of the striped adhesive layer. In the same figure a, 1 is the core wire, and the wire diameter is 0.23 mm.
It is made of tin-plated annealed copper wire. Reference numeral 2 denotes an insulator that covers the core wire 1, and is made of foamed polypropylene with a foaming rate of about 50% and a thickness of about 0.65 mm. 3 is the drain wire, wire diameter 0.26mm
The tin-plated annealed copper wire 4 is formed by wrapping a 12 μm thick aluminum foil polyester laminate tape. No. 1 to No. 10 indicate the strands constructed as described above, and P indicates the arrangement pitch between the core wires 1. In figures b and c, 5 is a flame-retardant polyvinyl chloride film with a thickness of 50 μm, 6 is a polyester tape with a thickness of 12 μm, 7 is an aluminum tape with a thickness of 10 μm,
8 is a thermoplastic resin stripe coat adhesive layer with a thickness of 5 μm, and 9 is a laminate of two 12 μm thick polyester tapes using a flame retardant adhesive. Depending on the material and thickness of the adhesive, the entire laminated tape flame-retardant polyester tape with a total thickness of 40 μm and whose oxygen index is controlled to be 28 or more, 1
0 indicates a thermoplastic resin solid coat adhesive layer with a thickness of 15 μm. Next, when manufacturing a flat cable, the upper and lower tapes are crimped from above and below the arranged strands No. 1 to No. 10 as shown by arrows A and B.
The cable is laminated by heating with a grooved hot roll, and the thermoplastic resin solid coat adhesive layer 10 is fused to each other from above and below to form a flat cable. In this case, an EVA-based thermoplastic resin is used, which can be fused at a low temperature so that the insulator 2 made of foamed polypropylene is not affected by the heating temperature of the heat roll. Fig. 2 shows a cross section of the flat cable manufactured in this way, in which the tapes 5 to 10 shown in Figs. No. 10 is shown laminated and fused from the top and bottom. FIG. 3 shows the peeling state of the stripe coat adhesive layer 8. This stripe coat adhesive layer 8 has a structure that allows it to be easily peeled off.
This is extremely convenient for terminal processing. Figure 4 shows the case where the VW-1 flame retardant test is applied to a flat cable, and shows a case where the flame of the burner 11 causes a warping phenomenon in the adhesive layer 8 as shown by arrow F. However, in the case of this example, even if such a warping phenomenon occurs, the flame-retardant polyester 9 with an oxygen index of 28 or higher does not ignite the flammable foamed polypropylene that is the insulator, and the flat cable Overall, it passes the VW-1 flame retardant test. This flat cable is used as a coaxial cable, and the characteristic impedance Z ₀ measured using the TDR (time domain reflectometer) method is Z ₀ =
95±5(Ω), delay time Td=4.1±0.12(n
sec/m), and satisfies not only the flame retardance but also the basic performance as a coaxial cable. As described above, it is possible to obtain a flat cable that satisfactorily passes the VW-1 flame retardant test of the UL standard. Furthermore, despite being coated with multilayer tape, the cable can have an extremely thin structure. Incidentally, as a comparative example, various experimental results are shown in Table 1.

[Table] The film configuration and cable used in the experiment have the same dimensions as in Figures 1 and 2. As shown in Table 1, even if the PVC film is a general mass-produced product with a flexibility temperature of less than 80°C, this flat cable can be flame-retardant if a flame-retardant polyester tape with an oxygen index of 28 or higher is used. Even if the polyvinyl chloride film shrinks and "warps", the burner flame will not ignite the insulator due to the presence of the flame-retardant polyester tape, and the UL
It passes the VW-1 flame retardant test. However, flammable polyester tape is rejected because the flame of the burner ignites it and causes it to burn. [Effects of the invention] According to the invention, a highly reliable flat cable that passes the VW-1 flame retardancy test can be provided.

[Brief explanation of the drawing]

Fig. 1 is a structural explanatory diagram showing one embodiment of the flat cable of the present invention, Fig. 2 is a cross-sectional view of the completed flat cable, Fig. 3 is an explanatory diagram of the peeling state of the stripe coat adhesive layer, and Fig. 4 is an explanatory diagram of the peeling state of the stripe coat adhesive layer. The figure is an application diagram of the VW-1 flame retardant test. 1... Core wire, 2... Core wire insulator, 3... Drain wire, 4... Aluminum foil polyester laminate tape, 5... Flame retardant polyvinyl chloride film,
6... Polyester tape, 7... Aluminum tape, 8... Stripe coat adhesive layer, 9... Flame retardant polyester tape, 10... Solid coat adhesive layer, 11... Burner.

Claims (1)

[Scope of utility model registration request] A flat cable made by arranging a large number of insulated wires in a plane and integrating them has an oxygen index of 30 or more, a longitudinal elongation of 0 to -15%, and a transverse elongation of 0 from the upper and lower outermost layers of the flat cable. ~+5% more flexible temperature: less than 80℃, thickness 10~
100μm flame retardant PVC film and thickness
2.6~25μm polyester tape, thickness 5.0~
A flat cable characterized by having a laminated tape of 25 μm aluminum tape and 25 to 100 μm thick polyester tape that is flame retardant with an oxygen index of 28 or more.