WO1996019744A1

WO1996019744A1 - Low-metsuke water-barrier material for communication cable and communication cable using it

Info

Publication number: WO1996019744A1
Application number: PCT/JP1995/002561
Authority: WO
Inventors: Yukio Sakuraba; Hirohumi Morishima
Original assignee: Tokai Rubber Industries, Ltd.
Priority date: 1994-12-19
Filing date: 1995-12-13
Publication date: 1996-06-27
Also published as: KR970701361A; CN1141083A; JPH08170070A

Abstract

A water-barrier tape which has an adequate rigidity and consequently can be wound around a communication cable without wrinkle. The material has a two-layer structure composed of a sheet substrate and a water absorbing material layer whose METSUKE (weight per square meter) is below 40 g/m2 or a sandwich structure composed of a pair of sheet substrates and a water absorbing material layer which is provided between the two sheets and whose METSUKE is below 40 g/m2. The rigidity value of the material in the longitudinal direction lies in a range of 0.2-1.5 gfcm2/cm, and that in the lateral direction in a range of 0.2-0.6 gfcm2/cm.

Description

Description Waterproofing material for Eve communication cable

And communication cable using it

The present invention relates to a low-weight type water-blocking material (water-blocking tape) used for stopping water between a cable core of a metal cable or an optical cable and a sheath material covering the outer periphery thereof, It concerns the communication cable used. Background art

In recent years, most of the obstacles in communication cables, especially optical fiber cables, are caused by water intrusion into the cables, and the intrusion of the water deteriorates the strength of the optical fiber or the water that has entered the fiber It freezes and compresses the optical fiber, causing problems such as impairing optical transmission characteristics.

Therefore, water-blocking materials (water-blocking tapes, water-blocking tapes, or water-blocking tapes) that have the property of preventing water from entering the optical fiber cable and reducing the length of entry even if water does enter. For example, those having a two-layer structure in which a water-absorbing composition layer is provided on a sheet substrate are disclosed in JP-A-H11-207377 and JP-A-1- Japanese Patent Application Laid-Open No. Hei 3 -224729, Japanese Patent Application Laid-Open No. Hei 357,623, and the like disclose a three-layer structure in which a cover cloth is further laminated on the water-absorbing composition layer. Has been presented. By the way, conventionally, for example, a water-blocking material disclosed in Japanese Patent Application Laid-Open No. Hei 13304145 is known. This water-blocking material contains epoxy groups in a carboxyl group in a cross-linked product of a copolymer of isobutylene and maleic anhydride in the form of an alkali metal salt such as sodium, potassium, lithium, or ammonium, or an ammonium salt. A mixture of a compound, a compound containing an amino group, and a crosslinking agent such as urea-melamine resin, which is heated and crosslinked and insolubilized, and an aqueous solution of a water-absorbing material is held on a sheet substrate serving as a support. Alternatively, an ammonium salt is held on a sheet substrate as a support using an adhesive. When the sheet base material as the support is, for example, a film-like or sheet-like cloth, non-woven fabric, or the like, these water-impervious materials are obtained by immersing the water-absorbent solution in these non-woven fabrics and then squeezing them with a mangle. A predetermined amount of the water absorbing composition is adhered to the sheet substrate. According to this water-blocking material, the water absorption ratio for artificial seawater is 3 times or more by the CB method, and it is said to be extremely excellent in water absorption.

On the other hand, a communication cable disclosed in Japanese Patent Application Laid-Open No. 6-203647 is known. As shown in Fig. 6, this communication cable has a core 64 with a large number of insulated metal wires 62, 62, ... bundled together by a binder 66, which is · Encased by plastic film 68 called wrap. In this case, the gap between the metal wires 62, 62, ... is filled with a petram-based / bolibutene-based jelly in the core 64, and the jelly, which is the filler material, leaks to the outside by the core wrap 68. It is considered not to be. A corrugated metal protective material 70 made of aluminum (A 1) stainless steel (SUS) is wound around the core tube 68, and the outer periphery thereof is covered with a sheath material 72. ing. And koa love The jelly-like filling composition containing extender oil as a main component also has a water stopping property between 68 and the metal protective material 70 or between the metal protective material 70 and the sheath material 72. Filled to keep.

However, such conventionally-known water-blocking materials for communication cables (water-blocking tapes) generally have high rigidity. Therefore, when this impermeable tape is wrapped around the cable, it floats up and the adaptability to the cable core is poor. If this is to be applied to a communication cable of the type disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 6-203637, for example, between a core rub of the communication cable and a metal protection material, or a metal protection material And the sheath material, but when this was actually applied, the rigidity of the water-blocking tape was too high, and there was a problem with the water stoppage.

On the other hand, if the water-blocking material (water-blocking tape) has low rigidity and softness, the seam will be easily formed unless the tension of the water-blocking tape is increased at the time of winding around the cable, and the sheath material will be covered. When the sheath material shrinks, a problem occurs that the waterproof tape is pushed in due to the contraction of the sheath material, thereby damaging the appearance of the communication cable. The present invention has been made in order to solve such a problem. However, by selecting the optimal range of rigidity of the water-blocking material (water-blocking tape), it is possible to avoid the floating or sinking phenomenon when winding the cable, and to improve the appearance and winding workability of the cable. The goal is to obtain good water stoppage. The present invention relates to a communication cable of the type disclosed in the above-mentioned Japanese Patent Application Laid-open No. Hei 6-230647, which is provided between a core rub wound around a cable core and a metal protective material, or between a metal protective material and a sheath. Focusing on the fact that it does not require so much water-stopping properties between the material and the cable, it is suitable for this type of application, so-called low-weight evening eve (evening amount of the water-absorbing composition is small per unit area) for communication cables. Providing impermeable material Things. Disclosure of the invention

In order to achieve this object, the first water-blocking material for a low-weight tie communication cable of the present invention is formed by forming a water-absorbing composition layer having a basis weight of 40 g / m ² or less on the surface of a sheet substrate. The stiffness value of the water-blocking material is in the range of 0.2 to 1.5 cm ² Zcm in the longitudinal direction, and is in the range of 0.2 to 0.6 cm ² / cm in the transverse direction. It is.

The second water-blocking material for a communication cable according to the present invention has a sandwich structure in which a water-absorbing composition layer having a basis weight of 40 g / m ² or less is interposed between a pair of sheet base materials. The point is that the rigidity value of the water barrier material is in the range of 0.2 to 1.5 gf cm ² Zcm in the vertical direction, and in the range of 0.2 to 0.6 gf cm ² / cm in the horizontal direction. That is what you do.

Here, examples of the sheet substrate include non-woven fabrics such as polyester fiber, polyamide fiber, polybrorene fiber, polyethylene fiber, polyacryl fiber, rayon, and vinylon, woven or knitted fabrics. A combination of any two of these synthetic fibers may be used.

The water-absorbing composition layer contains additives such as water-absorbing polymer particles, organic binders, other surfactants, antioxidants, and inorganic fillers. Examples of the water-absorbing polymer particles include crosslinked polyacrylates: neutralized starch-acrylic acid graft polymer, modified crosslinked polyvinyl alcohol, crosslinked isobutylene-maleic anhydride copolymer, and polyethylene oxide. Crosslinked product, Acrylamide Acrylic acid crosslinked polymer, etc. Is mentioned.

These water-absorbing polymer particles must fall apart from the sheet base material when they come in contact with water, but there is no particular limitation on the particle shape and particle size. Or a distorted shape. In addition, the particle size is preferably in a range (45 to 425 m) that does not slow down the rate of water absorption and swelling and does not delay falling off from the sheet base material. In order not to impair the water shielding of the micro gaps, it is desirable that particles having a particle size of 45 or less be contained to some extent (5% by weight or more). These water-absorbing polymer particles may be used alone or in combination of two or more.

Organic binders mainly include rubber-based materials and thermoplastic elastomer-synthetic resin-based materials. Rubber-based materials include styrene rubber, butyl rubber, butadiene rubber, isoprene rubber, ethylene-propylene rubber, chlorosulfonated polyethylene rubber, silicon rubber: chloroprene rubber, polyurethane rubber, acrylic rubber, chlorinated butyl rubber, and epichlorohydrin. Rubber and others.

The thermoplastic elastomer synthetic resin materials include ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, acrylonitrile butadiene copolymer, styrene-butadiene copolymer, polyester resin, and the like. Examples include polyamide resins, urethane resins, and other thermoplastic elastomers. These organic binders may be used alone or in combination of two or more of these rubber materials and synthetic resin materials, or may be a mixture of those obtained by random polymerization. The third and fourth aspects of the present invention correspond to the use inventions of the first and second aspects described above, and one of them is that a large number of communication lines are used. A bundle of communication lines formed and a waterproof jelly sheet interposed between the communication lines are wound with a live film, a metal protective sheet is wound around the outer periphery of the live film, and a sheath material is further wound around the outer periphery. A communication cable having a coating, wherein a water-blocking tape is interposed between the rub film and a metal protection sheet or between a metal protection sheet and a sheath material. Has a water-absorbing composition layer with a basis weight of 40 s / m ² or less on the surface, and the rigidity of the water-blocking bracket itself is 0.2 to 1.5 gf cm ² / cm in the vertical direction. The gist is that it is in the range of 0.2 to 0.6 cm ² Zcm in the horizontal direction.

In the other, a communication wire bundle formed by assembling a large number of communication lines and a waterproof jelly sheet interposed between the communication lines are wrapped around a wrap film, and the wrap film is formed. A communication cable in which a metal protective sheet is wrapped around the outer periphery and further covered with a sheath material on the outer periphery, wherein the communication cable is provided between the rub film and the metal protective sheet or between the metal protective sheet and the sheath material. A water-impervious tape is interposed between them, and this water-impervious tape has a sandwich structure having a water-absorbing composition layer with a basis weight of 40 g / ^z or less between a pair of sheet base materials. The stiffness of the impermeable tape itself is in the range of 0.2 to 1.5 gf cm ² / cm in the longitudinal direction, and is in the range of 0.2 to 0.6 gf cm ² / cm in the transverse direction. It is.

Thus, in the present invention, the rigidity of the waterproofing material (waterproofing tape) for a cable, whether it has a two-layer structure or a sandwich structure, can be determined in the vertical direction (tape length). Direction) 0.2 to: 1.5 gf cm ² / cm, and lateral (tape width direction) 0.2 to 0.6 gf cm ² / cm. . Soshi If therefore the nonwoven sheet substrate is a polyester-based example Te, in the case of two-layer structure that the nonwoven fabric weight is in the range of 25 to 70 g / m ^2, the nonwoven fabric weight in the case of the sandwich structure , 5-20 g / m ² .

If this impervious material does not meet either the longitudinal stiffness or the lateral stiffness, for example, the longitudinal stiffness is higher than 1.5 gf cm ² / cm, or the lateral stiffness If it is higher than 0.6 cm ² / cm, the water-impervious tape rises when the water-impervious material (water-impervious tape) is wrapped around the cable, creating a gap between the tape and between the tape and the core, resulting in water barrier. Not preferred.

—If the stiffness value in the longitudinal direction is less than 0.2 cm ² / cm, or the stiffness value in the transverse direction is less than 0.2 gf cm ² / cm, the tape will not seal when the tape is wound around the cable. When the sheath material is covered with the sheath material or when the sheath material is coated on the outside, the tape is pressed down by the contraction of the sheath material, and the appearance of the cable is impaired. BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 is a perspective view of the external appearance of a communication cable to which the present invention is applied, and Fig. 2 is a schematic diagram showing the main parts of a stiffness measurement test (KES method) used to confirm the effectiveness of the present invention. FIG. 3 is a diagram illustrating a method of evaluating the amount of water-impervious material sheet dropping into a cable core used to confirm the effectiveness of the present invention, and FIG. Fig. 5 is a perspective view of an L-shaped water impermeability measuring device, and Fig. 6 is an external perspective view of a conventionally known communication cable. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, examples of the present invention will be described in detail.

First, a schematic configuration of a communication cable to which the present invention is applied will be described with reference to FIG. The communication cable 10 shown in FIG. 1 has a large number of copper wires 1 2, 1 2... Bundled into one to form a cable core 14, and the cable core 14 is tied to a binding string 16. After that, it is wrapped with polyethylene terephthalate (PET) live film 18. A water-impervious tape 20 is wrapped around the live film 18 and the outside is covered with a corrugated metal protective material 22 such as aluminum foil or stainless steel foil, and a sheath material 24 Is coated. In this case, the space between the copper wires 12, 12,... Of the cable core 14 is filled with a jelly-like material (not shown) such as a petram type or a polybutene type. When water invades into 4, the jelly-like material prevents water from entering. Wrap film 18 prevents the jelly pieces from leaking out.

Table 1 below summarizes the types of test samples of the present invention and the comparative product and the test results.

In Table 1, test samples 1 to 5 show a two-layer water-blocking material (water-blocking tape) in which a water-absorbing composition layer is provided on a sheet substrate, and test samples 6 to 10 show front and back. This shows a sandwich-structured water-blocking material (water-blocking tape) in which both sides are sheet substrates and a water-absorbing composition layer is interposed between them. Of the two-layer structure of test samples 1 to 5, test samples 1 and 2 are comparative products, and test samples 3 to 5 are products of the present invention. Of the samples 4 to 10 having a sandwich structure, test samples 6 and 7 are comparative products, and test samples 8 to 10 are products of the present invention. Note that the test sample 11 is a so-called impregnated water-blocking material (water-blocking tape) disclosed in Japanese Patent Application Laid-Open No. Hei 13-30445 described as a conventional technique. Thus, the sheet base material of the water barrier material of each of the test samples 1 to 11 is made of a polyester spunbond nonwoven fabric. As shown in Table 1, the test samples 1 to 5 (two-layer structure) use the product name of “Munix 70xx xWTO” manufactured by Unitika, and the test samples 6 to 10 ( For the product with a sandwich structure, the product name “Eku-Ire” manufactured by Toyobo Co., Ltd. is used. For the test samples 1 to 5 (two-layer structure), the fineness of the polyester single yarn is 2 denier, and the weight of the nonwoven fabric is selected in several steps within the range of 20 to 80 g / m2. .

In the case of the test samples 4 to 10 (sandwich structure), the fineness of the polyester single yarn is still 2 denier, but the weight of the nonwoven fabric is several steps within a relatively narrow range of 10 to 30 g / m2. Is selected. On the other hand, as the water-absorbing composition, two kinds of compositions shown in Table 2 below were used. In the following description, all units “parts” mean “parts by weight”.

In Table 2, the water-absorbing compositions No. 1 and No. 2 are both water-absorbing resin polymers (Kuraray's trade name “KI Gel 201 K”), which are cross-linked metal salts of isobutylene-maleic acid copolymer. — F3 ”) The basic composition is 100 parts of organic binder with respect to 150 parts. _{C In} this case, the No. 1 water-absorbing composition uses styrene-butadiene-styrene (SBS) thermoplastic elastomer as the organic binder. Tomaichi (Califlex TR-1101, trade name, manufactured by Shell Chemicals) is blended, while butyl rubber (trade name, ezzobutyl # 268, manufactured by Etsuso) is used as an organic pinner in the No. 2 water-absorbing composition. Has been blended. These compositions are blended with 4 parts of a surfactant of polyethylene glycol (trade name “PEG600” manufactured by NOF Corporation) as an additive. In comparing the No. 1 water-absorbing composition with the No. 2 water-absorbing composition, It has been confirmed in various experiments that the rigidity of the water-blocking material (water-blocking tape) is higher when the No. 1 water-absorbing composition is used depending on the type of binder.

Table 1 shows which type of water-absorbing composition was used in each of the test samples 1 to 10.Table 1 also shows the amount of the water-absorbing composition applied. Is shown. For test samples 1 to 5 having a two-layer structure, the No. l water-absorbing composition was used, and the basis weight was constant at 20 g / m ² . Further information on test samples 6-10 of Sandi Dzuchi structure, using a water-absorbing composition No.2, its weight per unit area is constant at 30 g / m ^2.

These water-blocking materials (water-blocking tapes) are prepared by dissolving and dispersing the above-mentioned organic binder in an organic solvent such as toluene: methyl ethyl ketone and ethyl acetate using a stirrer. The particles are mixed, and further other additives are mixed if necessary. Then, this is coated on the surface of the sheet base material by using a barco, a mouth, a ruco, etc. to form a water-absorbing composition layer. In the case of a water-blocking material (water-blocking tape) having a sandwich structure, a predetermined water-blocking tape can be obtained by further laminating a sheet substrate on the surface of the water-absorbing composition layer.

In addition, the impregnated water-blocking tape of the test sample 11 shown as a comparative example is, specifically, a water-absorbing resin composition called “KI gel solution system” by Kuraray (isobutylene-maleic acid). 100 parts: 20 parts of Α solution and Β solution of a copolymer (mainly a crosslinked product of a metal salt) are mixed in a ratio of 100 parts: 20 parts, and the mixed solution is impregnated (penetrated) into the nonwoven fabric of the sheet base material. The desired amount of the water-absorbent resin composition is supported on the sheet substrate by squeezing with a wrench, etc. The sheet substrate is a polyester spunbond nonwoven fabric (trade name “Marix 70400WTO” manufactured by Unitika). ), Polyester Fineness 2 denier singles yarn, the adhesion amount of _c The water absorbing composition is used as a non-woven fabric weight 40 g / m ² is a 20 g / m ^2.

Next, various test results will be described. The test items include the rigidity characteristics (longitudinal and lateral directions) of the water-blocking material, the floating (falling) property to the cable core, and the water-blocking (L-shape), each of which is described below. Measured by the method.

(1) Rigidity characteristics

In each of the test samples 1 to 11, a sample 20 having a length of 20 cm x a width of 1 cm or more is sandwiched between the fixed chuck 32 and the movable chuck 34 (arranged at 1 cm intervals) of the device as shown in Fig. 2. Fix it. Then, the movable chuck is rotated in one direction around the fixed chuck in the range of curvature K = 2.5 to 102.5 (cm- ¹ ), and further rotated in the opposite direction to bend the sample. The bending stiffness value per unit length (unit: gf cmVcm) was measured (referred to as “KES method”). In order to measure the longitudinal stiffness and the lateral stiffness, we are using a cut-out sample of the water-blocking material (water-blocking tape) in the tape length direction and a cut-out sample in the table width direction.

(2) Lifting (Dip) Evaluation Test

As shown in Fig. 3, three round bars of 2 Omm ø are bundled, and a water-impervious tape 20 with a tape width of 4 Omm is wound around it with a weight of 5 kg, and the end of the water-impervious tape 20 is wound. 5 kg weight. At this time, as shown in FIG. 4, if the rigidity of the water-impervious tape 20 is high, the water-impervious tape 20 rises from the height of the round bar imitating the cable core, and the amount of floating is measured. If the rigidity of the tape 20 is low, the impermeable table 20 sinks below the height of the round bar, so the sinking amount was measured. The amount of rise (drop) is within the range of brass minus 2 mm. It is said.

(3) L-shaped water shielding

To explain the L-shaped water blocking, this is a test on how water can be blocked in the longitudinal direction of the cable when the cable is cut by external force and water enters from the cross section of the cable. is there. This device is described with reference to FIG. 5. The test piece is wound around a plastic rod 50 having an outer diameter of 1 Ommoi and passed through a glass tube 52 having an inner diameter of 11.1 mm0. The clearance between the glass tube and the glass tube is 0.6 mm). Then, a water supply pipe 56 is provided at one end of the simulated cable 54, a cock (not shown) is opened with the water supply pipe 56 filled with fresh water up to a height of lm, and water is injected into the cable 54. The length of the water running in the L-shape was evaluated based on how long the fresh water ran in the cable 54 and clogged.

Therefore, when examining the test results, first consider the test samples 1 to 5 having a two-layer structure. As a result, the test sample 1 of the comparative product has an excessively large lift and fails the L-shaped water-blocking ( On the other hand, Sample 2 was judged to be unacceptable because the drop amount was too large (X mark). On the other hand, in all of the test samples 3 to 5 of the product of the present invention, the floating (dip) amount was small, and good results were obtained in the winding workability and the L-shaped water shielding (marked with 〇). _C Next, when examining the test samples 6 to 10 with the sandwich structure, the test samples 6 and 7 of the comparative products have an excessively large floating amount, and the L-shaped water barrier is rejected (marked X). On the other hand, in all of the test samples 8 to 10 of the product of the present invention, the floating (drop) amount was small, and the winding workability and the L-shaped water-blocking property were good (marked with “〇”). Was done.

In addition, the test sample 11 of the comparative product also had an L-shaped Failed (marked X).

Considering these results, among the test samples 1 to 11, the test samples 1, 6, 7, and 1 1 with a large floating amount and L-shaped water impermeability were rejected were compared. ) Has a high rigidity value, especially in the longitudinal direction (table length direction), a large drop, and the winding workability is rejected. It can be seen that the values are low both in the vertical and horizontal directions. Judging from these results, the stiffness value is in the range of 0.2 to 1.5 gf cm ² / cm in the vertical direction (tape length direction) and 0.2 to 0.6 g in the horizontal direction (tape width direction): It is preferable to be within the range of f cm ² / cm because the amount of rise (drop) of the impermeable tape from the cable core can be suppressed to a considerable extent. Means for suppressing the amount of rise (fall) of the sheet base nonwoven fabric, the basis weight, the thickness of single yarn, the type of the water-absorbing composition, the presence or absence of embossing, etc. are effective. It seems to be.

In addition, in the present invention, various examples (test samples) were tested. However, the present invention is not limited to the above examples, and various modifications can be made without departing from the gist of the present invention. Industrial applications

As described above, the waterproofing material for a cable according to the present invention is described.

(Water-blocking tape) has a rigidity value in the vertical direction and a rigidity value in the horizontal direction that are within the appropriate range. This prevents the tape from being pressed down due to the shrinkage of the sheath material, improving the cable wrapping workability and providing a good cable appearance to the market. Also wrapped around the cable Occasionally, a tape having good water-stopping properties without lifting the tape and producing a gap between the tapes or between the tape and the core is obtained.

tiMS, book ft¾. . The present invention

1 2 3 4 5 6 7 8 9 10 11

3fck tape 2 layers sandwich layer «structure

Polyester type (Unitika tt «r Marix j) Polyester type« W (* ^ I «±« “ecoule j”) Unitika tt »sheet <<« <DIMW “Marix j

70800WTO 7O20OWTO 70 orchid TO listen OfTO 70300WTO 6251A 630 6101λ 615 "S201A 70400WT0 Sheet« «

No 80 20 40 60 30 25 30 10 15 20 40

(g / m *)

«BM» B £ »to No. 1 No. 2 1 <1 gel» liquid

System (A + B1 I Weight (g / m *) 20 20 20 20 20 30 30 30 30 30 20

M property value Length 2.5.0.20- 9 1.50.4 2.5.3.00.θ 1.2.1.53.0

Horizontal 0.60.1 0.3 0.4 0.2 0.8 0.9 0.3 0.5 0.6.1-0

Floating (fall

Vmm) + 4 1 3 ± 0 + 2 -1 + 3 + 4 ± 0 +1 + 2 + 4.5

If β X X O 0 O X X Ο Ο Ο X

O X O O O O O Ο Ο Ο X

Raw I

S? Sex (cm) 80 (x) 5 6 4 60 (x) 80 (x) 5 4 4 90 (x)

Overall rating ffi XXO 0 OXX Ο Ο Ο X

Water-absorbing composition

No. 1 No. 2

FfiflS polymer

Mono-maleic acid

150 150

V ¾Ι¾ 1¾Ι¾ππ¾5 · \ 丄 7 ^ ^ U 1 IN— r d ”In)

Yes Indah

Styrene-butadiene-styrene I Thermal ^ elastomer

(Selling ^ t product name 100 0

ΓCaliflex TR 1101 ")

Butyl rubber

(Etsuso brand name Desobutyl # 268j) | Department) 0 100

Interface '; SttJW

Polyethylene glycol 4 4

(Product name “PEG 600j” manufactured by Japan Corporation)

Claims

The scope of the claims

1. A water-blocking material for communication cables of low weight, which has a water-absorbing composition layer with a weight per unit area of 40 g / m ² or less on the surface of the sheet substrate, and has a rigidity value as the water-blocking material. Water-blocking material for a low-weight evening Eve communication cable, characterized in that the vertical direction is in the range of 0.2 to 1.5 gf cm ² / cm and the horizontal direction is in the range of 0.2 to 0.6 cm ² / cm.

2. The sheet substrate is a nonwoven fabric of polyester, low basis weight evening water shield for Eve communications cable according to claim 1 in which the non-woven fabric weight is characterized in that in the range of 25 to 70 g / m ² Wood.

3. A communication wire bundle formed by assembling a large number of communication lines and a waterproof jelly sheet interposed between the communication lines are wound with a rub film, and a metal protection sheet is wrapped around the outer periphery of the rub film. A communication cable wound around and further covered with a sheath material on the outer periphery thereof, wherein a water-blocking tape is interposed between the wrap film and the metal protection sheet or between the metal protection sheet and the sheath material. The water-impervious tape has a water-absorbing composition layer having a basis weight of 40 g / m ² or less on the surface of the sheet substrate, and the rigidity of the parenteral tape is 0.2 to 1.5 gfcm ² / A communication cable in the range of 0.2 to 0.6 gf cm ² / cm in the horizontal direction.

4. The sheet substrate is a nonwoven fabric of polyester, communication cable according to claim 3 in which the non-woven fabric weight is characterized in that in the range of 25~70 g / m ^2.

5. A water-absorbing material for a communication cable of a low-weight type in which a water-absorbing composition layer having a weight per unit area of 40 g / m ² or less is sandwiched between a pair of sheet base materials. The stiffness value of the material is in the range of 0.2 to 1.5 gfcm ² / cm in the longitudinal direction, and 0.2 to 0 in the transverse direction. Waterproofing material for communication cables with low weight, which is in the range of 6 gf cm ² / cm.

6. Each of the sheet substrate is a nonwoven Boriesuteru system, low according to claim 5, characterized in that the nonwoven weight of the respective sheet Ichito substrate is in the range of 5~ 20 s / m ² Waterproofing material for Eve communication cable.

7. A communication wire bundle formed by gathering a large number of communication lines and a waterproof jelly sheet interposed between the communication lines are wound with a rub film, and a metal protective sheet is wrapped around the outer periphery of the rub film. A communication cable which is wound and further covered with a sheath material on the outer periphery thereof, wherein a water-blocking tape is interposed between the rub film and the metal protection sheet or between the metal protection sheet and the sheath material. This water-impervious tape has a sandwich structure having a water-absorbing composition layer having a basis weight of 40 gZm ² or less between a pair of sheet base materials. A communication cable characterized by being in the range of 0.2 to 1.5 gfcm ² / cm in the direction and 0.2 to 0.6 gf cm ² / cm in the horizontal direction.

8. Each of the sheet substrate is a nonwoven fabric of polyester, communication according to claim 7 in which the nonwoven weight of the respective sheet Ichito substrate is characterized in that in the range of 5 to 20 g / m ² cable.