KR20060120097A - Drop optical fiber cable and frp tension member used for the cable - Google Patents

Abstract

A drop optical fiber cable, comprising optical fiber cores, surface coated tension members, and a support cable. The surface coated tension members are formed in a circular shape in cross section by covering fiber-reinforced thermosetting resin tension members with a thermoplastic resin coating layer, and the pair of surface coated tension members are disposed on both upper and lower sides of the optical fiber cores on a same axis at specified intervals. The support cable is disposed on the upper side of the tension members, and the optical fiber cores, surface coated tension members, and support cable are coated together with the thermoplastic resin body coating part. The tension members are formed by applying the thermoplastic resin coating layer onto FRP tension members. In this case, the outer periphery of the FRP tension members is anchored to the inner periphery of the coating layer. The thermoplastic resin used for the coating layer is selected from those resins which are compatible with the resin of the body coating part.

Description

FRP anti-tensile body used for drop optical fiber cable and drop optical fiber cable {DROP OPTICAL FIBER CABLE AND FRP TENSION MEMBER USED FOR THE CABLE}

TECHNICAL FIELD The present invention relates to a drop optical fiber of FRP agent used in a drop optical fiber cable and a drop optical fiber cable. In particular, a non-metallic drop optical fiber cable capable of being thin and thin and suitable as a drop wire, and a non-metallic drop optical fiber cable It relates to a FRP agent anti-tension body suitable for.

With the advent of the information society and the increase in the capacity of transmission information such as the Internet, the FTTH for laying fiber optic cables to subscribers such as buildings and houses is rapidly progressing.

As a drop optical fiber cable for FTTH, what used the metal wire for the tension body is proposed. (See JP 2001-337255 A, page 2, FIG. 1).

However, when a metal wire is used for the tensioning body, earth is necessary to avoid surging by thunder. In order to install earth, time is required for construction, and the burden of construction cost according to it is made, and it becomes an obstacle of the spread to each home. Thus, there has been a demand for a non-metallic drop optical fiber cable employing a non-metallic tension force body, which requires no earth construction.

Examples of the non-metallic anti-tension body used for this type of optical fiber cable include a fiber-reinforced synthetic resin (FRP) wire-shaped article. However, the FRP wire is simply used in place of the metal wire-tension body to provide a thermoplastic body coated. When adhesion with resin is difficult and adhesion is inadequate, an increase in optical transmission loss due to heat history, abnormality such as disconnection, etc. are caused, and it cannot function sufficiently as a drop optical fiber cable.

In this case, by applying an adhesive to the outer periphery of the hardened FRP wire or by coating the adhesive resin, it is also possible to enhance the adhesive force, but it is not useful, because it leads to an increase in cost due to the increase in the number of processes and materials, If the adhesion to the FRP is too strong, it is difficult and cumbersome to peel off the cover portion to be fixed to the star cluster cabinet during connection construction.

By the way, the present applicant discloses the manufacturing method of the rod-shaped thing of the thermoplastic resin coating fiber reinforced synthetic resin by which the FRP interface and thermoplastic resin coating were anchor-bonded. (See Japanese Patent Publication No. 63-2772)

This manufacturing method coats the uncured state reinforcement core formed by impregnating the uncured thermosetting resin into the bundle of the reinforcing fibers with a molten thermoplastic resin, and then immediately cooling and solidifying the coating layer of the thermoplastic resin, and then pressurizing the high temperature steam. The thermosetting resin is heated and cured while the reinforcing core portion and the interface portion of the coating layer are softened and in contact with each other in a fluidized state, and then the coated thermoplastic resin is cooled to form a core-reinforced thermosetting resin (FRP). And anchoring the coated thermoplastic resin.

However, when the rod-shaped object obtained by such a manufacturing method is used for the tensioning body of a drop optical fiber cable, there existed the technical subject demonstrated below.

That is, according to the manufacturing method disclosed in the above-mentioned publication, for example, when the glass fiber is made of reinforcing fibers and the thermosetting resin is coated with polyethylene using unsaturated polyester, the rod-shaped article is 106 kg / cm 2. Although the adhesive strength of about (10 MPa) can be obtained, there existed a problem that a coating surface was not necessarily smooth and it was difficult to obtain a uniform and thin diameter shaped object.

In addition, there is a technical problem that an anti-tension body made of FRP used in this kind of drop optical fiber cable is easily broken at a large bending diameter as compared with that made of metal. In order to reduce the bending diameter leading to the break, the FRP diameter What is necessary is just to make it small, but when reinforcing fibers are the same, it becomes a problem to reduce tensile strength.

In this case, the improvement related to the tensile strength alone can be solved by converting the reinforcing fiber into a high strength and high modulus type, but since a function (anti-shrinkage) that suppresses the shrinkage of the resin constituting the main body according to the change of environmental temperature is also required, As a means of lowering the contact area with the main body resin (anti-shrinkage becomes difficult to function), fine curing is not desirable, and there has been a demand for an FRP anti-tension body having a diameter substantially the same as before and having a small bending radius.

The present invention has been made in view of such a conventional problem, and is particularly lightweight in a drop optical fiber cable in which an optical tension core and a fiber-reinforced thermosetting resin (hereinafter sometimes referred to as FRP) are collectively coated with a thermoplastic resin. A primary object of the present invention is to obtain a non-metallic drop optical fiber cable which can be made thin and has desirable characteristics as a drop wire.

Further, a second object is to provide an FRP anti-tension body that has a large bending diameter and is not easily broken.

MEANS TO SOLVE THE PROBLEM In order to achieve the said objective, this invention provides the thermoplastic resin by which the coating tension tension body which formed the coating layer of thermoplastic resin in the anti tension body of fiber reinforced thermosetting resin, the optical fiber core wire, the said coating tension body, and the said optical fiber core wire are collectively. A drop optical fiber cable having a main body covering part coated with a film, wherein the outer surface of the coated tension body and the main body covering were fused and bonded together, and the inner circumference of the coating layer and the outer circumference of the tension body were anchor bonded.

The said covering tension tension body can form the said coating layer of 0.3 mm or less in the said tension tension body whose outer diameter which uses glass fiber as a reinforcement fiber is 0.9 mm or less.

LLDPE can be used for the coating layer made of the said thermoplastic resin of the said coating | tension anti tension.

The said coating tension body can make the pulling force 10N / 10mm or more.

The said coating tension body can arrange | position two with the said optical fiber core wire between them, and predetermined intervals above and below.

The said tension body can use a glass thread for reinforcement fiber.

The said glass yarn has a single fiber diameter of 3-13 micrometers, and can use the thing of the single yarn shape which did not combine several yarns.

Moreover, in this invention, the tensile elasticity modulus of the said reinforcement fiber was 360 cN / dtex or more, and the elongation at break was 3.5% or more in the FRP agent tension body which bound the reinforcement fiber with the thermosetting resin.

The said thermosetting resin can be made into vinyl ester resin.

The said FRP anti-tension body is used for the drop optical fiber cable which has the coating tension tension body which formed the coating layer of thermoplastic resin in the outer periphery, and the main body coating part which coat | covers an optical fiber core wire and the said coating tension tension body with a thermoplastic resin collectively, The said The outer circumference of the coating layer and the main body covering portion may be fused and bonded to each other, and the inner circumference of the coating layer and the outer circumference of the anti-tension body may be anchor bonded.

The tension tension member made of FRP is formed in a flat cross section, such as an ellipse or a rectangle, and can be disposed so as to have a small thickness with respect to the bending direction when the drop optical fiber cable is laid.

1 is a cross-sectional view showing an embodiment of a drop optical fiber cable according to the present invention.

2 is an explanatory diagram of a method for measuring the drawing (adhesive) force of the coated tensile tension body used in the drop optical fiber cable of the present invention.

3 is an explanatory diagram of an ironing test of a drop optical fiber cable of the present invention.

4 is a cross-sectional view showing an example of a drop optical fiber cable using the FRP agent tension body and the FRP agent tension body according to the present invention.

FIG. 5: is explanatory drawing at the time of laying the drop optical fiber cable shown in FIG.

FIG. 6 is an explanatory view of the detention used when forming the main body covering part of the drop optical fiber cable shown in FIG.

7 is a cross-sectional view showing another example of a drop optical fiber cable using the FRP agent tension body and the FRP agent tension body according to the present invention.

8 is an explanatory diagram when confirming the bending laying property of the drop optical fiber cable according to the present invention.

EMBODIMENT OF THE INVENTION Below, the best form for implementing this invention is demonstrated in detail based on an Example and a specific example.

1 shows an embodiment of a drop optical fiber cable according to the present invention. The drop optical fiber cable 1 shown in FIG. 1 is provided with the optical fiber core wires 2 and 3, the cover tension body 6, and the support line 7 (also called messenger wire). The optical fiber cores 2 and 3 are arrange | positioned so that the center may adjoin up and down.

The coated tension tension body 6 is formed in the circular cross section which coat | covered the tension tension body 4 of fiber reinforced thermosetting resin (made by FRP) with the coating layer 5 made of thermoplastic resin, and a pair of coating tension force ( 6) is arrange | positioned on the coaxially so that it may be provided between the optical fiber core wires 2 and 3 at predetermined intervals.

The support line 7 is disposed above one of the covering tension members 6, and the optical fiber core wires 2, 3, the covering tension members 6, and the support lines 7 are formed of a thermoplastic resin main body covering part ( 8) is provided with the structure coat | covered collectively. In addition, the support line 7 is joined via the thin part 10 so that it may be isolate | separated from another part.

As mentioned above, the drop optical fiber cable 1 comprised in this way is constructed between the telephone poles using the support line 7, and when it enters into a subscriber's house, first, the narrow part 10 is cut | disconnected and the support line 7 is isolate | separated. Next, the optical fiber core wires 2 and 3 are taken out from the part of the notch 9, and the subscriber side and the core wires 2 and 3 are connected.

The coated anti-tension 6 forms a coating layer 5 made of thermoplastic resin on the anti-tension 4 made of a fiber-reinforced thermosetting resin (FRP). In this case, the outer periphery of the FRP agent tension body 4 and the inner periphery of the coating layer 5 are anchored to each other.

In order to obtain anchor bonding, the method described in JP-A-63-2772, that is, the uncured state reinforcement core formed by impregnating the uncured thermosetting resin into the bundle of reinforcing fibers is melted, and immediately after that, the coating layer of the thermoplastic resin. After cooling and solidifying, this was led to a hardening tank of pressurized high temperature steam, and the thermosetting resin was heated and cured while the reinforcing core portion and the interface portion of the coating layer were softened and flowed in contact with each other. What is necessary is just to anchor-bond a core part interface which consists of thermosetting resins (FRP), and a coating thermoplastic resin.

As the reinforcing fibers that can be used in the present invention, various glass fibers, aromatic polyamide fibers, carbon fibers, and the like are generally selected according to the required tensile strength and elastic modulus.

In the case of using glass fibers, in order to thin the FRP anti-tension body 4 to a diameter of 0.9 mm or less, a glass seal is preferable, and is selected by the performance required from glass fibers such as E, S, and T, but economical E glass is recommended for cotton.

As a glass thread, the short fiber diameter which comprises is 3-13 micrometers, the thing of the single yarn shape which does not combine several yarns is preferable, and 11.2-67.5Tex is used.

In this case, when the number of times is high, that is, when the glass seal exceeding 67.5Tex is used, it will adversely affect the roundness at the time of FRP, and it will be difficult to carry out uniform coating in the subsequent thin coating molding process with a thermoplastic resin. Lose. On the other hand, although 11.2Tex and below are commercially available, the process is complicated and costs increase, which is uneconomical.

For selecting the glass yarn, the yarn is twisted, for example, 1 piece / inch, and the glass short fibers are less brittle, loosened or entangled in the impregnation or throttle process of the thermosetting resin, This is because an unstretched rod-like article having a uniform outer circumference is obtained.

Although the volume content rate of the glass fiber of the anti-tension body 4 is determined by the required physical property, in the present invention for the purpose of further thinning, it is preferably about 60 to 70% by volume.

As the thermosetting resin that can be used in the present invention, a terephthalic acid-based or isophthalic acid-based unsaturated polyester resin, a vinyl ester resin or an epoxy resin is generally used, and a curing catalyst or the like is added thereto.

The thermoplastic resin used for the coating layer 5 of the unhardened state reinforcement core part is selected from resins compatible with the thermoplastic resin of the main body covering part 8, and when a flame-retardant resin is used for the main body covering part 8, In order to improve the compatibility with the resin, it is preferable to use an adhesive resin or to add a master batch of the adhesive resin, and further, to match the color of the main body coating part 8, the master batch for coloring. You may add and color.

In addition, the thermoplastic resin used for the coating layer 5 may perform various modifications for imparting flame retardance in accordance with flame retardation of the main body coating part 8. In addition, in order for the thermoplastic resin used for the coating layer 5 to obtain the anchor adhesive structure with the FRP anti-tension body 4, it is preferable that at least an inner periphery exhibits a molten state or a softened state at the time of heat-hardening of a thermosetting resin, and hardens Polyolefin resin which has melting | fusing point or a softening point in the range of temperature 110-150 degreeC is more preferable.

In addition, in the case of using the glass thread as a reinforcing fiber, the coated anti-tension body 6 is preferably a fiber-reinforced thermosetting resin cured product having an outer diameter of 0.9 mm or less in terms of bending resistance and fine curing. Since the coating thickness more than necessary as a main body resin requires a flame retardance, it is preferable that the coating layer 5 shall be 0.3 mm or less.

In addition, the thickness of the coating layer 5 is more preferably about 0.07 to 0.2 mm after shaping for the purpose of thinning, and for such thin film, a resin having good thin film formability is preferable, for example, Low density polyethylene (LDPE), linear low density polyethylene (LLDPE), etc. are preferable.

When using LLDPE, it is more preferable to use what has the following characteristics. The characteristic is that the MFR according to JIS K 6760 is 1 to 4 g / 10 min, the density is 0.920 to 0.940 g / cm 3, and in the tensile test according to JIS Z 1702, the tensile strength is 30 MPa or more, and the 1% modulus is 150 to 250 MPa. It has a range of values.

It is preferable that pull-out force of the tension-tightening body 4 from the thermoplastic resin used for the coating layer 5 is 10N / 10mm or more in the coating-tension body 6 used for the drop optical fiber cable of this invention.

This drawing force was made into the index of the adhesive force by anchor bonding structure, and it measured by the following measuring methods.

While preparing a tester with a measuring jig 11 having a perforation hole slightly larger in diameter than the outer diameter of the FRP core, the coating layer 5 at the end of the covering tension member 6 was peeled off, and the coating layer 5 was subsequently connected. ), A cut of 10 mm in length was cut out with a razor, and a sample S in which a coating layer 5 of 10 mm in length was left was prepared. As shown in FIG. 2, the sample S was inserted into the hole of the testing machine, loaded with a tensile load at a rate of 50 mm / min, and the pulling force was obtained from the chart.

4 and 5 show another embodiment of the drop optical fiber cable using the FRP agent tension body and the FRP agent tension body according to the present invention. The drop optical fiber cable 1a shown in these figures is equipped with the optical fiber core wire 2a, the coating tension body 6a, and the support line (messenger wire) 7a.

The coated tension tension body 6a is formed in the flat rectangular cross section which coat | covered the tension tension body 4a made from fiber reinforced thermosetting resin with the coating layer 5a made from thermoplastic resin, and a pair of coating tension tension body 6a is The optical fiber core wires 2a are arranged coaxially with predetermined intervals above and below the optical fiber core wire 2a.

The support line 7a is disposed above one of the covering tension members 6a, and the optical fiber core 2a, the covering tension members 6a, and the supporting lines 7a are the main body covering portions 8a made of thermoplastic resin. It is equipped with the structure covered by collectively. The main body covering part 8a is formed so as to correspond to both sides of the optical fiber core wire 2a so that a pair of notches 9a may oppose.

In addition, a circular main body covering part 8a is formed on the outer circumference of the support line 7a, and the support line 7a is connected by the narrow part 10a so as to be separated from the other parts.

As mentioned above, the drop optical fiber cable 1a comprised in this way is constructed between the telephone poles using the support line 7a, and when it enters into a subscriber house, first, as shown in FIG. 5, the narrow part 10a is cut | disconnected. Then, the support line 7a is separated, and then separated from the notch 9a portion, the optical fiber core 2a is taken out, and the subscriber side and the core 2a are connected.

In the case of the present Example, the coating | tightening tension body 6a forms the coating layer 5a of thermoplastic resin in the tension-tightening body 4a made from fiber reinforced thermosetting resin (henceforth FRP).

In this case, as the reinforcing fibers of the anti-tension 4a, for example, aramid fibers, polyallylate fibers, polyparaphenylene benzobisoxazole (PBO) fibers and the like, the tensile modulus is 360 cN / dtex or more. The elongation at break at 3.5% or more is appropriately selected.

In this case, when the tensile modulus is 360 cN / dtex or less, the tensile strength for protecting the optical fiber core wire 2a is not sufficiently obtained, and thus cannot fulfill its role.

If the elongation at break is 3.5% or less, the FRP tends to bend, and it becomes difficult to reduce the bending radius when the drop optical fiber cable is formed.

That is, the continuous use allowable bending radius becomes large, and it is necessary to lay it at a large bending radius at the time of laying (indirectly, the smaller the minimum bending diameter can make the bending radius (or diameter) smaller at the time of laying). . More preferable tensile modulus is 480 cN / dtex or more.

As the reinforcing fibers to be used, 500 to 3500 dtex, which is preferably a so-called multifilament shape having a single fiber diameter of 10 to 15 µm and not joining a plurality of yarns, is used.

In this case, when the number of times is high, that is, when reinforcing fibers of more than 3500 dtex are used, it is possible to adversely affect the roundness when FRP is used, and to apply uniform coating in the thin coating coating step with a thermoplastic resin. Becomes difficult.

Moreover, there exists a possibility that the alignment of a single yarn may worsen and tension performance may become inadequate when FRP is formed. On the other hand, although a thread of 500 dtex or less is commercially available, the process is complicated and leads to an increase in cost, which is uneconomical.

The thermosetting resin which can be used for binding the reinforcing fibers of the present invention is generally a terephthalic acid or isophthalic acid unsaturated polyester resin, a vinyl ester resin (such as an epoxy acrylate resin), an epoxy resin, or the like. Although it is used adding a catalyst for a solvent, vinyl ester resin (epoxy acrylate resin etc.) is preferable especially from a physical property, such as heat resistance.

The thermoplastic resin used for the coating layer 5a of the uncured reinforcement core part is selected from resins compatible with the thermoplastic resin of the main body covering part 8a, and when a flame-retardant resin is used for the main body covering part 8a, In order to improve the compatibility with the resin, it is preferable to use an adhesive resin or to add a master batch of the adhesive resin, and even if the colored master batch is added and colored according to the color of the main body coating, do.

In addition, the thermoplastic resin used for the coating layer 5a may be subjected to various modifications for imparting flame retardance in accordance with flame retardation of the main body coating part 8a. Moreover, in order for the thermoplastic resin used for the coating layer 5a to acquire the anchor adhesive structure with a FRP part, it is preferable that at least the inner periphery exhibits a molten shape or a softened state at the time of heat-hardening of a thermosetting resin, and hardening temperature 110- Polyolefin resin which has melting | fusing point or a softening point in the range of l50 degreeC is more suitable.

When the glass fiber is used as a reinforcing fiber, the FRP part is preferably a fiber-reinforced thermosetting resin cured product having an outer diameter of 0.9 mm or less in terms of bending resistance and fine curing (more preferably, 0.6 mm or less). In the case where the fineness and the flame retardancy are not imparted to the coating layer 5a, when the flame retardance is required for the main body resin, the coating thickness more than necessary becomes a deterioration factor of the flame retardancy, so that the coating layer 5a is 0.3 mm. It is preferable to set it as follows.

Moreover, as for the thickness of the coating layer 5a, 0.08 mm or more is preferable for the coating thickness before a normal diameter, and it is more preferable to set it as the thickness of 0.07 to about 0.2 mm by diameter-fining a surface layer for the purpose of fine-hardening.

In order to thin the coating thickness before a diameter, resin with good thin film formability is preferable, for example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), etc. are preferable.

Although the shape of the FRP coating anti-tension body 6a of this invention is not specifically limited, It forms in flat cross sections, such as an ellipse and a rectangle, and especially, when laying the drop optical fiber cable 1, the bending direction (FIG. 4). In the vertical direction, the bending radius can be made smaller and the laying property can be further improved by arranging the thickness of the anti-tension body 3 made of FRP small (see also the fourth and fifth degrees).

FIG. 6 shows another embodiment of a drop optical fiber cable using the FRP agent tension body and the FRP agent tension body according to the present invention, and the same or equivalent parts as those in the above embodiment are given the same numerals, and the description thereof will be described. In addition to the above, only the feature points will be described in detail below.

The drop optical fiber cable 1b shown in FIG. 6 is equipped with the optical fiber core wire 2b, the coating | coated anti-tension body 6b, and the support line 7b. The coated tension tension body 6b is formed in the circular cross section which coat | covered the tension tension body 4b made from fiber reinforced thermosetting resin with the coating layer 5b made from thermoplastic resin, and a pair of covering tension force body 6b, It is arrange | positioned on the same axis | shaft so that this may be provided between the optical fiber core wires 2b at predetermined intervals.

The support line 7b is disposed above one of the cover tension members 6b, and the optical fiber core wire 2b, the cover tension member 6b, and the support line 7b are the main body covering part 8b made of thermoplastic resin. It is equipped with the structure covered by collectively. The main body covering part 8b is formed so as to correspond to both sides of the optical fiber core wire 2b so that a pair of notches 9b may oppose.

Moreover, the main body covering part 8b of circular shape is formed in the outer periphery of the support line 7b, The support line 7b is connected by the narrow part 10b so that it may be isolate | separated from the other part. The configuration is substantially the same as in the above embodiment.

As the reinforcing fibers of the anti-tension 4b, for example, among aramid fibers, polyallylate fibers, polyparaphenylene benzobisoxazole (PBO) fibers, and the like, the tensile modulus is 360 cN / dtex or more, and at the time of breaking Choose an elongation of at least 3.5%. Also in the embodiment comprised in this way, the effect similar to the said Example can be obtained.

EMBODIMENT OF THE INVENTION Below, although a more specific Example of this invention is described, this invention is not limited to the following Example.

Embodiment 1

In a resin impregnation tank in which a thermosetting catalyst was added to a vinyl ester resin (manufactured by Mitsui Chemical Co., Ltd .: H8100), 9 pieces of E glass yarns having a single yarn diameter of 10 µm and 22.5Tex (manufactured by Nitto Spinning Company: ECEN225 1/0 1.0ZR) were guided. Guide through the throttle nozzle, the inner diameter of which is gradually reduced, throttle-molding the uncured resin, and obtain a rod-shaped material having a fine diameter of 0.4 mm in outer diameter. 200 L) and coated with LLDPE resin (TUF2060, manufactured by Nippon Unicar Company), having a black master batch added MI = 2.4, a density of 0.921 g / cm 3 and a 1% modulus of 170 MPa by a 30 µm cast film. It was coated in a ring shape with a thickness of 0.21 mm, immediately guided to a cooling bath, and cooled and solidified the coating on the surface.

Subsequently, the coated uncured linear product was guided to a pressurized steam curing tank having pressurized seals formed at the inlet and the outlet, and cured at a vapor pressure of 23.5 Pa. Then, the dies with an internal diameter of 0.93 mm and 0.70 mm heated to 265 ° C. were formed. The guide outer circumferential surface was guided | guided by the provided shaping | molding machine, the coating tension tension body 6 of 0.7 mm of coating outer diameters was obtained, and it wound up in the bobbin in continuous shape.

The coated tensile tension member 6 had a glass fiber content of 63.5% by volume and a pull force of 12 N / 10 mm measured using the measuring jig 11 shown in FIG. 2. In addition, in the 24-hour heat-resistant bending diameter test in 80 degreeC heat, 30 mm is cleared, and the heat cycle test of -30 degreeC-80 degreeC is repeated 3 times at 1000 mm of sample lengths, and the coating layer of the coating tension body 6 is carried out. Although the adhesion state of (5) and the tensioning body 4 was observed, shrinkage of the coating layer 5 hardly occurred.

The pullout force at the time of changing the hardening temperature at the time of manufacture of the coating | coated tension-tightening body 6, and heat | fever bend resistance are put together in the following Table 1 as an experiment example.

Using this coated tension tension line, the drop optical fiber cable 1 of the structure shown in FIG. 1 was manufactured with the following method.

As the support line 7, two steel wires having an outer diameter of 1.2 mm, optical fiber core wires 2 and 3 having a diameter of 0.25 mm, and two of the above-described sheathing tension members 6 are arranged at predetermined intervals and inserted into the crosshead die. , The main body coating part 8 was formed of the flame-retardant polyethylene resin, and the drop optical fiber cable 1 which has the notch 9 in the center part was obtained.

The ironing characteristic of the obtained drop optical fiber cable 1 was measured using the ironing tester of the measurement system shown in FIG. In Fig. 3, reference numeral 1 denotes a drop optical fiber cable to be tested, reference numerals 12, 13 and 14 denote a traction line, reference numeral 15 denotes a bent tube through which the optical fiber cable 1 is inserted, and a curvature of R300 mm. Bent Reference numeral 16 denotes a weight that applies a predetermined load to the optical fiber cable 1 through the pull string 12.

Using this tester, the heat cycle of -30 degreeC-+80 degreeC was repeated 5 times with a load of 34.3N, ironing length 1m, and temperature conditions, and the transmission loss in the light source of wavelength 1550nm was measured. The measurement results are collectively shown in Table 2 below.

Shrinkage of each coating layer was not observed in the drop optical fiber cable produced by the coating tension-tightening body 6 of the specific example 1. As shown in FIG.

Embodiments 2 and 3

Specific examples 1 and 2 except that the pressure of the pressurized steam curing tank in Specific Example 1 were set to 15.7 Pa (specific example 2) and 32.4 Pa (specific example 3), and the curing tank internal temperature was set at 125 ° C and 145 ° C. In the same manner, a coated tensile tension line was obtained.

The pull-out force of the obtained coating tension line was 11.3 (specific example 2) and 15N / 10mm (specific example 3), and cleared 30 mm in all at 24 degreeC heat-resistant bending diameter test in 80 degreeC hot.

Using the coated tensile tension lines of Embodiments 2 and 3, the same drop optical fiber cable was produced as in Embodiment 1, but there was no increase in transmission loss in the ironing test of the obtained drop optical fiber cable, and increased transmission loss in the heat cycle test. Was also not recognized.

Comparative Example 1

In Example 1, the coating tension tension body was obtained like Example 1 except having hardened | cured by setting the vapor pressure of the pressurized steam hardening tank to 8.8 Pa, and making the internal temperature of the hardening tank 115 degreeC. The pull-out force of the obtained coating tension body was 7N / 10mm, and in the heat-resistant bending test of 24 mm at 80 degreeC of 30 mm diameter, the whole sample was broken and 30 mm diameter could not be cleared.

Comparative Example 2

In Example 1, LLDPE resin (NUCG-5350 manufactured by Nippon Unicar) having a density of 0.928 g / cm 3, MFR l.3 g / 10min, tensile strength of 18 Mpa, and 1% modulus of 340 Mpa was used as the coating resin of the uncured fine-rod rod-shaped material. The coating was coated in a ring shape at a coating thickness of 0.21 mm, immediately led to a cooling bath, and the surface coating was cooled and solidified.

Subsequently, the coated uncured linear product was guided to a pressurized steam curing tank having pressurized seals formed at the inlet and the outlet, and cured at a vapor pressure of 23.5 Pa. Then, the dies with an internal diameter of 0.93 mm and 0.70 mm heated to 265 ° C. were formed. The guide outer peripheral surface was guided | guided by the provided shaping | molding machine, the coating tension tension body 6 of 0.7 mm of coating outer diameters was obtained, and it wound up in the bobbin in continuous shape.

The obtained coating tension body had the hardening defect part by the pinhole of coating partly, and was unable to satisfy the physical property as an tension tension body.

Comparative Examples 3 and 4

The specific example except having changed into the glass thread of 22.5Tex of the specific example 1, and used three glass yarns of 67.5Tex (comparative example 3), and three yarns which combined three 22.5Tex yarns as each twist yarn (comparative example 4) In the same manner as in 1, a coating tension body was obtained.

The obtained coating tension body did not disperse | distribute glass fiber uniformly in the cross section of an FRP part, and the roundness fell in a knot shape, and when it bends, it was directional and it could not be used as an tension tension body.

Particularly, in Comparative Example 4 using three bonded yarns, in the impregnation step of the unsaturated polyester resin, the combined yarns were loosened, length deviation occurred between the yarns, and fluff and the like occurred. Therefore, a pinhole generate | occur | produced in the coating process of a thermoplastic resin, and the hardening part partially generate | occur | produced after hardening.

Moreover, the outer periphery of FRP of the obtained coating tension body was not uniform, the coating thickness after shaping | uniform was uneven to the diameter of 0.70Φ, and the FRP part was partially exposed, and it was unsuitable as an tension tension body in some cases.

This is considered to be due to insufficient dispersion of glass fibers and easy variation in a predetermined dimension and 0.4 mm in outer diameter in this comparative example.

Cloth Adhesion (N / cm) Heat resistance bending diameter 80 ℃ 24 hours 30mmφ 5 tests Heat Cycle -30 ℃ → 80 ℃ 3 Cycle Shrinkage (%) Embodiment 1 12 5/5 OK 0 Embodiment 2 11.3 5/5 OK 0 Embodiment 3 15 5/5 OK 0 Comparative Example 1 7 0/5 NG 0

 Ironing properties Heat cycle -30 degrees Celsius → 80 degrees Celsius 5 cycles Embodiment 1 Good Good Embodiment 2 Good Good Embodiment 3 Good Good Comparative Example 1 Bad Bad

Note: A transmission loss of 0.3 dB / km or less is considered good.

As is evident from the above specific examples and comparative examples, the drop optical fiber cable according to the present invention includes a coated tensile tension body in which a thermoplastic resin coating layer is formed on an anti-tension body made of a fiber-reinforced thermosetting resin cured product, and an optical fiber core wire collectively made of a thermoplastic resin body. As the coating, the outer tension body outer sheath and the main body sheath are fused, and the anti-tension body made of the fiber-reinforced thermosetting resin cured product of the coated tension tension body has an anchor adhesive structure, and thus the tension force suppresses heat shrinkage of the main body sheath. By effectively protecting the optical fiber core wire, the heat cycle test and the ironing test are satisfied.

Moreover, since the drop optical fiber cable which concerns on this invention is an anchor bonding structure, exposure of the tension-tension body of the core part in a connection operation can be easily peeled off by cutting off the coating layer. For this reason, compared with the drop optical cable using the conventional adhesive which requires cutting | disconnection by a cutlery, or the use of a solvent, the fixing operation to a star cluster cabinet can be performed safely and easily in a favorable environment, According to this invention It can provide a narrow, practical non-metallic drop fiber optic cable.

Embodiment 4

4.6% elongation at break in the resin impregnation tank to which the thermosetting catalyst (powder arc irradiation manufacture, Caddox B-CH50: 4 parts, Kayabutyl B: 1 part) was added to vinyl ester resin (Japan Composite company make: ester H8100), A para-aramid fiber having a tensile modulus of 520 cN / dtex (Teijin: Technora T240, single filament diameter 12 μm, 1670 dtex) was guided through a guide, followed by a throttle nozzle having a small internal diameter in steps. Induction, throttle-molding the uncured resin, to obtain a rod-shaped object having a diameter of 0.5mm outside, this was added to the black master batch through the cross head die (200 ℃) of the melt extruder, MI = 2.4, density 0.921 1% modulus by cast film of g / cm <3>, 30 micrometers is 170 MPa LLDPE resin (TUF2060 by the Japan Unicar Co., Ltd.), it coat | covered in annular shape at 0.25 mm of coating thickness, and immediately guide | induced to a cooling tank, and surface The coating part of was cooled and solidified.

Subsequently, the coated uncured linear product was guided to a 18 m long pressurized steam curing tank having a pressurized seal at the inlet and outlet at a speed of 15 m / min, and cured at a vapor pressure of 32.5 Pa (145 ° C.), followed by 210 ° C. It guide | induced to the warp machine provided with the inner diameter 1.0mm and 0.8mm diameter die heated by stage at -250 degreeC, and diameter-coated outer peripheral surface was obtained, and the coating tension-tightening body 6b of circular cross section whose coating outer diameter is 0.8mm was obtained, and bobbin was obtained. Wound into a continuous shape. Subsequently, the bobbin was subjected to dry heat treatment (secondary heat treatment) for 40 hours in a constant temperature chamber at 40 ° C.

The coated tensile tension member 6b has a content ratio of 61.1% by volume of the reinforcing fiber in the FRP portion, and a minimum bending diameter (a loop diameter immediately before bending failure occurs while the coated tensile force member is made into a loop shape and the loop is made smaller). 6mm.

Embodiment 5

The same method as in Example 4, except that a multi-filament of a para-aramid fiber (made by Toray DuPont: Kefra 29, single yarn diameter 12 μm, 1670 dtex) having a breaking elongation of 3.6% and a tensile modulus of elasticity of 490 cN / dtex was used as the reinforcing fiber. The coated tensile tension body 6b of circular cross section was obtained.

The coated tensile tension member 6b has a content ratio of 58.9% by volume of the reinforcing fiber in the FRP portion, and the minimum bending diameter (the loop diameter immediately before bending failure occurs while bending the coated tensile force body in a loop shape and making the loop small) is 5 mm.

The coated tensile tension members 6b obtained in the specific examples 4 and 5 were subjected to a 24-hour heat-resistant bending diameter test at 80 ° C. hot, respectively, and were cleared at 30 mm, and the sample length was 1000 mm to -30 ° C. to 80 ° C. heat. When the cycle test was repeated three times and the adhesion state between the coating layer 5b of the coating anti-tension 6b and the anti-tension 4b of the FRP agent was observed, shrinkage of the coating layer hardly occurred in both cases, and showed good results. It was.

Next, as the support line 7b, one φ 1.2 mm bluing end steel wire, two coated tensile tension members 6b obtained in Example 1, and φ 0.25 mm single mode fiber 1 as the optical fiber core wire 2b. The dog is guided to the crosshead die, extrusion-coated with a mold of a shape as shown in Fig. 7, using flame-retardant PE (Nuniq. Primary cooling was performed in the temperature-controlled hot water cooling tank, and secondary cooling was performed next in the water cooling tank, and the drop cable 1b of the cross-sectional structure as shown in FIG. 6 was obtained.

In order to confirm the laying property of the obtained drop cable 1b, as shown in FIG. 8, when laying at the wall corner part r = 15mm (diameter 30mm), the problem that a FRP is broken does not arise, but it is favorable. The results are shown.

Comparative Example 5

The same method as in Example 4, except that a multi-filament of para-aramid fibers (made by Toray DuPont: Kefra 129, single yarn diameter 12 μm, 1670 dtex) having a breaking elongation of 3.3% and a tensile modulus of 670 cN / dtex was used as the reinforcing fiber. As a result, a coated tensile strength body was obtained.

The coated tensile tension member had a content of 58.9% by volume of the reinforcing fiber in the FRP portion, and a minimum bending diameter (the loop diameter immediately before bending breakage occurred while the coated tensile force body was looped and the loop was small) was 8 mm.

Comparative Example 6

The same method as in Example 4, except that a multi-filament of para-aramid fibers (made by Toray DuPont: Kefra 49, single yarn diameter 12 μm, 1670 dtex) having a breaking elongation of 2.4% and a tensile modulus of 780 cN / dtex was used as the reinforcing fiber. The coated tension body was obtained.

The coated tensile tension body had a content ratio of 55.8% by volume of the reinforcing fiber in the FRP portion, and the minimum bending diameter (the loop diameter immediately before bending failure occurred while bending the coated tensile force body in a loop shape and becoming small) was 10.5 mm. It was.

As is clear from the above specific examples and comparative examples, according to the FRP agent tension member according to the present invention, a FRP agent tension member having a small bending radius can be obtained without reducing the required tension and anti-compressibility. By using it, since the drop optical fiber cable excellent in laying property can be obtained, the following can be said.

That is, the anti-tension body of the FRP agent has a technical problem that it is easy to be broken at a large bending diameter compared to that of the metal, including the ones described in the specific examples 1 to 3 above, and the bending diameter leading to the breakage is increased. In order to make it small, what is necessary is just to make small FRP diameter, but when reinforcing fiber is the same, decreasing a pull force becomes a problem.

In this case, only the improvement of the tensile strength can be solved by converting the reinforcing fibers into a high strength and high modulus type. As a means for lowering the contact area with the main body resin (anti-shrinkage becomes difficult to function), fine curing is not preferable, and there is a need for an FRP agent-tension body having a diameter substantially the same as the conventional one and a small bending radius. The anti-tension body of the FRP agent according to the present invention can fully satisfy this request.

According to the drop optical fiber cable of the present invention, since it is light and thin, it can be effectively utilized as an optical fiber placed in a subscriber house.

Moreover, according to this FRP agent tension body in this invention, the FRP agent tension body with a small bending radius can be obtained, without reducing the required tension and anticompression property, and using this FRP agent tension body, the drop excellent in laying property is provided. Since an optical fiber is obtained, it can utilize effectively at the time of laying a subscriber house.

Claims (11)

A drop optical fiber having a coated tension tension body in which a coating layer made of thermoplastic resin is formed on an FRP agent tension body of fiber-reinforced thermosetting resin, an optical fiber core wire, and a main body coating portion which collectively coats the coating tension tension body and the optical fiber core wire with a thermoplastic resin. In the cable, And the outer periphery of the coating layer and the outer periphery of the anti-tension body are anchor-bonded to each other. The drop optical fiber cable according to claim 1, wherein the coated tensioning body forms the coating layer of 0.3mm or less in the FRP agent tensioning body having an outer diameter of 0.9mm or less, which is made of glass fiber. The drop optical fiber cable according to claim 1 or 2, wherein LLDPE is used for the thermoplastic resin coating layer of the covering tension member. The drop optical fiber cable according to any one of claims 1 to 3, wherein the coated tension tension member has a drawing force of 10 N / 10 mm or more. The drop optical fiber cable according to any one of claims 1 to 4, wherein two of the coated tension tension members are disposed with the optical fiber core wires interposed therebetween and spaced apart from each other by a predetermined interval. The drop optical fiber cable according to any one of claims 1 to 5, wherein the anti-tension body uses a glass yarn for reinforcing fibers. 7. The drop optical fiber cable according to any one of claims 1 to 6, wherein the glass yarn has a single fiber diameter of 3 to 13 µm and a single yarn shape in which a plurality of yarns are not joined. An FRP anti-tension body in which a reinforcing fiber is bound with a thermosetting resin, wherein the tensile elasticity modulus of the reinforcing fiber is 360 cN / dtex or more, and the elongation at break is 3.5% or more. The anti-tension agent of an FRP agent according to claim 8, wherein the thermosetting resin is a vinyl ester resin. 10. The main body coating according to claim 8 or 9, wherein the FRP anti-tension body comprises a coating anti-tension body having a thermoplastic resin coating layer formed on its outer periphery, an optical fiber core wire, and the coating anti-tension body collectively coated with a thermoplastic resin. An anti-tensile body made of FRP, which is used for a drop optical fiber cable having a part, and is fused and adhered to the outer circumference of the coating layer and the main body covering, and anchor-bonds the inner circumference of the coating layer and the outer circumference of the anti-tension body. The FRP agent according to claim 10, wherein the FRP agent tension member is formed in a flat cross section, such as an ellipse or a rectangle, and is disposed so as to have a small thickness with respect to the bending direction when the drop optical fiber cable is laid. Tension body.

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