JPH04357623A - Waterproof tape for cable - Google Patents

Abstract

PURPOSE:To provide a waterproof tape with high waterproof performance, capable of preventing the water absorption resin powder from being exfoliated from end portions of the tape when cutting into a practical use width or taping a cable, preventing its surface from becoming sticky or preventing the blocking between the tape portions even when the tape absorbs water in the high- humidity environment, for example, in a rainy season, and not decomposed by microbe. CONSTITUTION:A waterproof tape comprises a base material member 1 one, or both surfaces of which have a water absorption resin layer 2 composed as essential components, and a resin binder 4, at least one of which is covered by a covering material member 5. Preferably, the base material member 1 covering material 5, water absorption resin 3 and resin binder 4 are made to have antifungal properties to prevent the generation of hydrogen.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to optical fiber cables,
This relates to a water stop tape used for power cables and the like to prevent water from running.

0002

2. Description of the Related Art Conventionally, it is a well-known technique to use water-stop tapes to prevent water from entering communication cables such as optical fiber cables, power cables, and the like.

For example, FIG. 2 is a sectional view showing an example of the structure of a waterproof relay optical fiber cable. FR in the center
A plurality of optical fiber tape core wires 10 are housed in the grooves 7a of a grooved polyethylene spacer 7 which has a P tensile strength body 6 and has a spiral groove on its outer periphery, and further includes a water stop tape 8 and a polyethylene jacket 9. It is provided. When the outer sheath of a cable such as the one described above deteriorates or is damaged due to some kind of accident and water infiltrates into the cable, the water-stop tape placed under the outer sheath passes through the outer sheath and enters. Excellent water-stopping technology that absorbs water and expands, stopping the water only near the point where it enters, preventing water from running in the longitudinal direction or inside the cable, and preventing accidents caused by water on the cable. It has a function.

[0004] These water-stop tapes for cables include:
(1) Multiple layers of water-absorbing swelling layers made of a mixture of highly water-absorbent resin powder and low-melting point adhesive resin powder are placed between two base nonwoven fabrics, and a base nonwoven fabric is placed between each water-absorbing swelling layer. Interposed sandwich type water stop tape (Japanese Patent Application Laid-Open No. 63-3014
Publication No. 18).

(2) Application-type water-stop tape in which a coating solution containing a powder or granular water-absorbing resin and a resin binder is applied to one or both sides of a polyester long fiber nonwoven fabric sheet (Japanese Utility Model Publication No. 129228/1982) ).

[0006] has been proposed.

[0007]

[Problems to be Solved by the Invention] However, these conventional water stop tapes each have the following problems. (1) Sandwich type water-stop tape has the excellent advantage that since the water-absorbing resin powder is not exposed on the surface, there are no problems such as stickiness or blocking even if the water-stop tape absorbs moisture. However, in this type of water-stop tape, the water-absorbing resin powder is not fixed to the non-woven fabric, so when cutting a wide sheet into a tape of practical width, or when taping a cable, the tape may be cut or cut. There is a problem that the water-absorbing resin powder sometimes falls off from the edge of the tape.

(2) Since the water-absorbing resin powder of the coated type water-stop tape is fixed with a binder, the water-absorbing resin powder does not fall off from the end of the tape when cutting a wide sheet into a tape shape or cutting it. It has its advantages. However, since the water-absorbing resin powder is exposed on the surface, if the water-stop tape absorbs moisture in a high-humidity environment such as during the rainy season, the surface will become sticky, and in the worst case, blocking will occur, making it unusable. For this reason, consideration must be given to air conditioning during the manufacturing process of the water-stop tape, during storage of the water-stop tape, and even when taping the cable, which poses a problem in that care must be taken when handling the tape.

An object of the present invention is to prevent the water-absorbing resin powder from falling off from the end of the tape when cutting it to a practical width or taping it to a cable, and to prevent the water-absorbing resin powder from falling off from the end of the tape when cutting it to a practical width or taping it to a cable, and to prevent the water-absorbing resin powder from falling off in a high humidity environment such as the rainy season. Even if the water tape absorbs moisture, the surface will become sticky,
To provide a water stop tape that does not cause blocking among the tapes, is not decomposed by microorganisms, and has excellent water stop performance.

0010

[Means for Solving the Problems] The water-stop tape of the present invention which solves the above-mentioned problems has a water-absorbing resin layer containing a water-absorbing resin and a resin binder as essential components on one or both sides of a base material, At least one of the water-absorbing resin layers is covered with a cover material.

More specifically, the water-stop tape of the present invention includes powdered or granular water-absorbing resin, synthetic resin, or synthetic rubber on one or both sides of a synthetic resin film, or a woven or nonwoven sheet made of synthetic fibers. After applying a water-absorbing resin composition containing a binder as an essential component, a cover material made of synthetic fiber is further bonded to at least one side of the water-absorbing resin composition.

[0012] The base material used in the present invention is preferably one that has strength to withstand tension during coating processing or taping to a cable, is not decomposed by microorganisms, and is flexible. Therefore, the base material is preferably a synthetic resin film, or a woven or nonwoven sheet made of synthetic fibers.
In terms of materials, polypropylene, nylon, polyester,
Acrylic can be used, but from the viewpoint of price and strength,
Preference is given to long-fiber nonwoven sheets produced by the spunbond process.

[0013] The synthetic resin or synthetic rubber binder used in the present invention has the effect of making the water-absorbing resin adhere to the base material and the low basis weight nonwoven fabric sheet to the water-absorbing resin layer, and is a binder that is biodegradable by microorganisms. It is a 100% synthetic product. As synthetic resin or synthetic rubber, acrylic resin,
Preferred are polyurethane resins, unsaturated polyester resins, ethylene copolymer resins, polyamide resins, silicone resins, polyisobutylene, butyl rubber, acrylic rubber, ethylene/propylene rubber, silicone rubber, and the like, which do not contain halogen atoms.

The powder or granular water-absorbing resin used in the present invention is a synthetic polymer that does not dissolve when it comes into contact with water, has a water-absorbing capacity of several tens to several thousand times its own weight, and is biodegradable. For example, acrylate-based crosslinked products, saponified vinyl acetate/acrylic acid ester copolymers, polyvinyl alcohol/maleic anhydride reactants, isobutylene/maleic acid copolymer crosslinked products. Preferred are acrylic acid salts/acrylamide copolymers, modified polyethylene oxides, and the like, which may be used alone or in combination of two or more. The amount of the water-absorbing resin to be blended is preferably 100 to 2000 parts by weight per 100 parts by weight of the binder. If the amount is less than 100% by weight, the water-stopping effect will not be exhibited, and if it is more than 2,000 parts by weight, the water-absorbing resin will drop off significantly from the side surface of the water-stopping tape cut to a practical width.

The cover material used in the present invention prevents the tapes from blocking each other when the water stop tapes are left in a high humidity environment such as during the rainy season and absorbs significant moisture, and also prevents the tapes from blocking each other during taping to cables. It is used to prevent problems such as staining, has an appropriate gap so as not to impede the water-stopping performance of the water-stop tape, is not decomposed by microorganisms, and can withstand the tension during the bonding process. Must. Therefore, as a cover material, a nonwoven fabric sheet made of synthetic fibers is preferable, and polypropylene, polyethylene, nylon, polyester, and acrylic can be used from the material standpoint, but from the viewpoint of cost and strength, it is preferable to use spunbond or melt-blown sheets. Advantageously, long-fiber nonwoven sheets are used. The basis weight of the cover material is preferably 5 to 20 g/m2. If it is less than 5g/m2, it will not be possible to obtain sufficient tension when bonding the cover material.
Furthermore, blocking cannot be prevented when the water-stop tape absorbs moisture in a high-humidity environment, and if the cover material exceeds 20 g/m2, the void area between the fibers of the cover material is too small, so when the water-stop tape comes into contact with water, the water-absorbing resin This is because it inhibits water absorbing, swelling and falling off, significantly reducing water-stopping performance.

The water-absorbing resin composition used in the present invention is dissolved and dispersed in an organic solvent to form a coating material for coating on a substrate. Any organic solvent that can dissolve the binder synthetic resin or synthetic rubber can be used, such as toluene, xylene, benzene, methyl ethyl ketone, acetone, hexane, methyl isobutylene, ethyl acetate, dioxane, tetrahydrofuran, cyclohexane, General purpose solvents such as alcohol are suitable.

In addition to the above-mentioned compounding agents, the water-absorbing resin composition used in the present invention may contain the following compounding agents depending on the purpose. For example, powdered or granular thermoplastic resins such as polyethylene or ethylene copolymers to improve the adhesion between the base material and cover material, and crosslinking agents to crosslink or vulcanize synthetic resins and synthetic rubbers as binders. , vulcanizing agents, rust inhibitors to prevent corrosion of metal shielding layers such as copper, wetting agents to improve water absorption properties of water absorption layers and increase water absorption performance, fillers to reduce costs, These include flame retardants to impart flame resistance, conductive substances to impart conductivity, and processing aids to improve processability.

For example, when a flame retardant such as aluminum hydroxide or magnesium hydroxide is blended into the water-absorbing resin composition, a flame-retardant water-stop tape can be obtained.

[0019] The water stop tape can be formed by various methods. An example will be explained below.

[0020] A binder, a water-absorbing resin, an organic solvent,
If necessary, take the desired amount of powdered or granular thermoplastic resin, filler, anti-aging agent, wetting agent, etc., and mill it in a ball mill.
Thoroughly dissolve and mix using a stirrer or the like to obtain a water absorbent resin composition. The obtained water absorbent resin composition is applied to a base material by a known coating method, a cover material is attached with the water absorbent resin layer containing a solvent, and then dried, or the water absorbent resin composition is coated as a base material. After coating the material and drying it, the cover material is attached using a hot roll or embossing roll. If necessary, heat treatment is performed to harden.

[0021]

[Function] The water stop tape for cables of the present invention will be explained in detail with reference to the drawings. FIG. 1 is a sectional view showing an example of the structure of the water-stop tape for cables of the present invention. In the water-stop tape for cables of the present invention, a water-absorbing resin composition 2 is coated on one side of a base material 1 made of a synthetic resin film, a synthetic fiber fabric, or a non-woven fabric sheet, and a cover material 5 is further attached thereon. It is combined. 3 indicates a water-absorbing resin, and 4 indicates a binder.

The water-absorbent resin 3 is fixed with a binder 4, and a cover material 5 is attached to the water-absorbent resin layer, so that the water-absorbent resin 3 is bonded to the water-absorbent resin layer during cutting to a practical width or taping to a cable. Even if the water-stop tape absorbs moisture in a high-humidity environment, there will be no problems such as blocking the water-stop tape or staining guide rolls during the cable taping process. It has excellent characteristics.

Furthermore, the water-stopping tape for cables of the present invention has excellent water-stopping ability and is not decomposed by microorganisms, so it does not generate hydrogen gas that is harmful to optical fibers. Since the viscosity of the water-absorbing gel does not decrease due to decomposition, it has long-term reliability of several decades. The water-stop tape for cables of the present invention can be used not only for optical fiber communication cables and copper conductor communication cables, but also as a pressure wrapping tape for power cables, control cables, etc., and has a very wide range of applications.
This is extremely advantageous in practice.

[0024]

【Example】

Example 100 parts by weight of ethylene/propylene rubber and 50 parts by weight of water-absorbing resin (Nippon Shokubai Chemical Co., Ltd.: Aqualic CS-7)
0 parts by weight, 3 parts by weight of anti-aging agent, 1 part by weight of wetting agent, and 20 parts by weight of polyethylene powder (particle size: about 100 μm).
parts by weight and 800 parts by weight of toluene were placed in a stirring container, and stirred and dissolved using a stirrer to obtain a water absorbent resin composition. Next, this water-absorbing resin composition was applied to one side of a polyester long fiber nonwoven fabric (manufactured by Asahi Kasei Industries, Ltd.: ES5060) at a dry adhesion amount of 100.
Coat and dry at g/m2. Next, a cover material (manufactured by Sunrex Industries Co., Ltd., polypropylene non-woven fabric, basis weight 12 g/m2) is pasted onto the dried water-absorbing resin layer using an embossing roll, cut to a width of 35 mm, and water-stop tape for cables is attached. Obtained. During cutting, the water-absorbing resin did not fall off from the cut side of the water-stop tape, confirming that it was fixed by the binder. The thickness of the tape is 0.28mm, and the unit weight is 17
It was 2g/m2.

Comparative Example In line with the example, a water-absorbing resin composition was applied in a dry amount of 100g/100g/100g/dry to one side of polyester long fiber nonwoven fabric ES5060.
It was coated and dried in 2 m2, and cut to a width of 35 mm to obtain a coated type water-stop tape for cables. The thickness of the tape is 0.2
7 mm, and the unit weight was 160 g/m2.

Moisture Absorption Test In order to confirm the anti-blocking effect of the water stop tape of the present invention upon moisture absorption, the following mock test was conducted.

That is, the water-stop tapes of the example and comparative example were each cut to a length of 50 mm, 10 sheets were stacked one on top of the other, sandwiched between glass plates, a load of 5 kg was applied, and the temperature was 40° C. and the humidity was 90%. The treatment was carried out for 24 hours in a constant temperature and humidity chamber. After processing, I removed the load and tried peeling off the tapes that had overlapped each other. The tape of the example had no stickiness or blocking and could be easily peeled off. On the other hand, the water stop tape of the comparative example was sticky and caused blocking, making it difficult to peel off.

Antibacterial Test In order to confirm the antibacterial properties of the water stop tape, a test was conducted using the following method.

4 g of the test sample, 4 g of ammonium dihydrogen phosphate, which acts as an accelerator in the antibacterial test, and 200 cc of the soil extract described below are placed in a 300 cc Erlenmeyer flask, mixed, and then sealed with a silicone stopper. Then, store it in the shade at 30°C, and periodically extract 1 cc of the air from the top of the Erlenmeyer flask until after 30 days, analyze the generated gas using a gas chromatograph, and examine the color and condition of the solution with the naked eye. For comparison, a test sample of pulp that is decomposed by microorganisms will be tested at the same time.

[0030] The soil extract is prepared as follows.

(1) The soil includes fallen leaves, etc., and is collected from a waterside where grass grows.

(2) Mix 500 g of soil with 2000 cc of pure water and stir.

(3) After standing for 12 hours, the supernatant liquid is filtered, and 150 cc of pure water is added to 50 cc of the filtrate to obtain a soil extract.

[0034] As a result of the test, in the pulp test sample, hydrogen gas, which is an indicator of corrosive action by microorganisms, was significantly generated, and mold growth was also observed. On the other hand, in the test samples of the water stop tapes of Examples and Comparative Examples, no hydrogen gas was generated and no changes such as mold growth were observed.

Therefore, it was confirmed that the water-stop tape for cables of the present invention has excellent antibacterial properties.

Simulated water-stopping test In order to confirm the water-stopping effect of the water-stopping tape, the following mock test was conducted.

That is, a spacer for a 100-core IF cable with a length of 11 m (number of grooves: 5 grooves/groove dimensions: width 1.6 mm,
Five optical fiber tape core wires were placed in each of the five grooves (depth 2.5 mm), and a 35 mm wide water stop tape was wrapped thereon with a 5 mm wrap with the water absorbing side facing inward. Furthermore, a polyester single-sided adhesive tape was wrapped around the water-stop tape instead of the polyethylene jacket to create a simulated optical fiber cable. Three simulated optical fiber cables were prepared for each of the water stop tapes of Examples and Comparative Examples.

Next, a vinyl chloride pipe is connected to one end of this simulated optical fiber cable, and the connection is sealed to prevent water leakage. With this simulated cable placed horizontally, artificial seawater (Aquamarine for metal corrosion testing, manufactured by Yasu Pharmaceutical Co., Ltd.) was flowed through the vinyl chloride pipe at a water pressure of 1 m. After this state was maintained for 24 hours, the vinyl chloride pipe was removed, the polyester single-sided adhesive tape and the water stop tape were peeled off, and the water travel distance in each groove was measured.

The results are as follows, and it was confirmed that by bonding the cover material together, the water running distance did not become significantly longer and an excellent water stopping effect was achieved.

[0040]

[Table 1]

[0041]

[Effects of the Invention] The water-stop tape of the present invention uses a synthetic resin film, synthetic fiber woven fabric, or non-woven fabric sheet as a base material, and a water-absorbing resin is fixed with a synthetic resin or synthetic rubber binder. The composition is sandwiched between cover materials. Because these materials are 100% synthetic, they do not break down with microorganisms and produce hydrogen gas, which is harmful to fiber optic cables, giving the cables long-term reliability. Moreover, the water-absorbent resin powder or particles will not fall off from the water-stop tape during processing, and even if the water-stop tape is exposed to a high humidity environment for a long time, it will not become sticky or cause blocking. It is extremely easy to handle because it does not require air conditioning equipment to control humidity during the production of water-stop tape, storage of water-stop tape, and cable production. Furthermore, there is almost no decrease in water-stopping performance due to providing the cover material on the water-absorbing resin layer, and the film has excellent water-stopping performance.

The water-stop tape for cables of the present invention can be used not only for optical fiber cables but also for copper conductor communication cables, power cables, control cables, etc., and has a very wide range of applications and is extremely useful in practical use. Useful.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing an example of the water-stop tape for cables of the present invention.

FIG. 2 is a sectional view showing an example of an optical fiber cable to which a water-stop tape for cables is applied.

[Explanation of symbols]

1 Base material 2 Water-absorbing resin composition 3 Water-absorbing resin 4 Binder 5 Cover material 6 FRP tensile strength body 7 Grooved polyethylene spacer 7a Groove 8 Water stop tape 9 Polyethylene outer sheath 10 Optical fiber tape core wire

Claims (2)

[Claims] Claim 1: A water-absorbing resin layer containing a water-absorbing resin and a resin binder as essential components on one or both sides of the base material,
A water-stop tape for cables, characterized in that at least one of the water-absorbing resin layers is covered with a cover material. 2. A water-stop tape for cables, characterized in that the base material, cover material, water-absorbing resin, and resin binder have antibacterial properties.