JP5323731B2 - Flame retardant optical fiber cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical fiber cable which can reduce damage of an optical fiber due to oviposition behavior of a cryptotympana facialis and which can ensure passing property to a pipe line and workability for removing outer coat of a terminal without losing fire resistance. <P>SOLUTION: A fire-resistant optical fiber cable has an optical fiber core wire on which a coat is formed at an outer periphery, and a tension member arranged in parallel to a longitudinal direction of the optical fiber core wire, and the optical fiber core wire and the tension member are coated using a fire-resistant resin composition (P) which contains (B) 10 to 60 pts.mass of metal hydrate and (C) 1 to 8 pts.mass of red phosphorus with respect to 100 pts.mass of a thermoplastic resin composition (A) containing (a) 85 to 15 mass% of ethylene-&alpha;-olefin copolymer, (b) 10 to 80 mass% of a polypropylene based resin and 0 to 20 mass% of (c-1) unsaturated carboxylic acid or polyolefin based resin altered with its derivative, and/or (c-2) ethylene-(meth)acrylic acid copolymer. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a flame retardant optical fiber cable. More specifically, the present invention relates to a flame-retardant optical fiber cable that can reduce an increase in transmission loss due to optical fiber damage caused by the spawning behavior of bearfish.

As an optical fiber cable, one or a plurality of single-core optical fiber cores, optical fiber tape cores, and other optical fibers, and tension members and support wires made of steel wire, aramid resin, etc., are collectively covered with a sheath having a neck. What is configured as such is known.
By the way, when this fiber optic cable is installed aerial, the optical fiber is damaged in the spawning tube by semi-particularly Komazemi mistakenly laying the spawn tube into the sheath and spawning inside the fiber optic cable mistakenly as a tree trunk or branch. At the same time, moisture such as rainwater can easily enter the cable from the portion where the laying tube is pierced. When moisture enters the cable, there is a high risk that the moisture causes an increase in transmission loss in the optical fiber core.
Thus, an optical fiber cable has been proposed in which a protective tape is disposed on the inside or the outer surface of the sheath so as to cover at least a part of the optical fiber core covered with the sheath (see, for example, Patent Document 1).
On the other hand, this optical fiber cable is required to be flame retardant. Therefore, an optical fiber cable that mixes a large amount of metal hydrate as a flame retardant and constitutes a sheath using a flame retardant resin composition having a hardness equal to or higher than a predetermined value to reduce the piercing of the laying oviduct Has been proposed (see, for example, Patent Document 2).

JP 2006-313314 A WO 2008/90880 pamphlet

However, in the optical fiber cable of Patent Document 1, it is difficult to prevent damage to the optical fiber core wire when the egg-laying tube is pierced obliquely while avoiding the protective tape.
Moreover, the optical fiber cable which comprised the sheath using the flame-retardant resin composition with which many metal hydrates were mix | blended shows the outstanding flame retardance. However, an optical fiber cable with a sheath made of a resin composition containing a large amount of metal hydrate peels off at the interface between the metal hydrate and the resin and applies a slight external force to the sheath surface. Prone to trauma.
Furthermore, it is necessary to improve molding processability when a sheath is formed using a flame retardant resin composition containing a metal hydrate to produce an optical fiber cable. Moreover, an optical fiber cable is often installed indoors in a laid pipe line. For this reason, the lineability of the optical fiber cable into the pipeline and the work of removing the outer jacket of the terminal are required. However, optical fiber cables with a sheath made of a flame retardant resin composition containing a large amount of metal hydrate often have insufficient surface smoothness, and the outer cover work of the terminal cannot be performed well. There is.
The present invention can reduce the damage of the optical fiber due to the spawning behavior of the bearfish, can suppress the increase in transmission loss while ensuring the flame retardancy, It is an object of the present invention to provide an optical fiber cable excellent in outer cover removal workability.

As a result of intensive studies on the above problems, the present inventors have arranged an optical fiber core wire whose outer periphery is coated with an ultraviolet curable resin composition, and is arranged in parallel in the longitudinal direction of the optical fiber core wire. It has been found that a flame retardant optical fiber cable including a tension member, the optical fiber core wire and the tension member being covered with a specific flame retardant resin composition can solve the above-mentioned problems. The present invention has been made based on this finding.
That is, the present invention
<1> An optical fiber core wire having a coating formed on the outer periphery using an ultraviolet curable resin composition, and a tension member arranged in parallel in the longitudinal direction of the optical fiber core wire,
(A) an ethylene-α-olefin copolymer 85 to 15% by mass, (b) a polypropylene resin 10 to 80% by mass, and (c-1) a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, and / Or (c-2) 10 to 50 parts by mass of (B) metal hydrate with respect to 100 parts by mass of thermoplastic resin component (A) composed of 0 to 20% by mass of ethylene- (meth) acrylic acid copolymer. part below and (C) red phosphorus 1-8 parts by weight flame-retardant resin composition containing a (P) (where the flame retardant resin composition (P) is (meth) acrylate and / or acrylic crosslinked With no auxiliary)
A flame retardant optical fiber cable, wherein the optical fiber core wire and the tension member are coated;
<2> An optical fiber core wire having a coating formed on the outer periphery using an ultraviolet curable resin composition, and a tension member arranged in parallel in the longitudinal direction of the optical fiber core wire,
(A) an ethylene-α-olefin copolymer 85 to 15% by mass, (b) a polypropylene resin 10 to 80% by mass, and (c-1) a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, and / Or (c-2) 10 to 30 parts by mass of (B) metal hydrate and 100 parts by mass of the thermoplastic resin component (A) composed of 0 to 20% by mass of ethylene- (meth) acrylic acid copolymer and (C) Flame retardant resin composition (P) containing 1 to 8 parts by weight of red phosphorus (However, the flame retardant resin composition (P) is a (meth) acrylate-based and / or acrylic-based crosslinking aid). Not included)
A flame retardant optical fiber cable, wherein the optical fiber core wire and the tension member are coated;
< 3 > The flame retardant resin composition (P) contains 0.5 to 4 parts by mass of a silicone compound with respect to 100 parts by mass of the thermoplastic resin component (A). <1> or <2 > Flame retardant optical fiber cable,
< 4 > The flame-retardant light according to any one of <1> to <3>, wherein the density of the (a) ethylene-α-olefin copolymer is 940 kg / m ³ or less. Fiber cable,
< 5 > The flame-retardant optical fiber cable according to any one of <1> to < 4 >, wherein the (b) polypropylene resin is a propylene homopolymer,
< 6 > Any one of <1> to < 5 >, wherein the metal hydrate is untreated magnesium hydroxide and / or magnesium hydroxide whose surface is treated with a silane coupling agent. flame-retardant optical fiber cable according to claim, and <7> molded body using the flame-retardant resin composition (P) is,請<1> to the <6>, wherein the composed of a single layer The flame-retardant optical fiber cable according to any one of the above,
Is to provide.

  The flame-retardant optical fiber cable of the present invention can reduce the damage of the optical fiber due to the spawning behavior of the bearfish, and does not impair the flame retardancy. Workability can be ensured.

It is a schematic sectional drawing which shows one Embodiment of the optical fiber cable of this invention.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing an embodiment of the present invention. The optical fiber cable 1 of the present invention has four optical fiber cores 2, a support wire 4 made of φ1.2 mm steel wire, and two tension members 3, 3 ′ made of φ0.5 mm aramid FRP. The sheath 6 having the neck portion 5 is collectively covered.
The optical fiber core wire 2 is formed by arranging a plurality of optical fiber strands (four in FIG. 1) coated with a primary coating or a secondary coating immediately after drawing a glass optical fiber and performing a collective coating. . In FIG. 1, the optical fiber core wire has four cores, but is not limited to four cores.
The optical fiber is coated with a resin composition such as an ultraviolet curable resin, for example, an ultraviolet curable urethane acrylate, and a cured coating is formed by irradiation with ultraviolet rays. The batch coating is also performed by using an ultraviolet curable resin composition, such as an ultraviolet curable urethane acrylate or epoxy acrylate resin composition, and is cured by irradiating with ultraviolet rays.
The tension member is arranged in parallel with the longitudinal direction of the optical fiber core wire.
As shown in FIG. 1, for example, the sheath 6 excluding the support line has a long side of 3.8 mm, a short side of 2.0 mm, a length and thickness of the neck 5 of 0.2 mm, and the sheath 6 covering the support line 4. The outer diameter of the optical fiber cable 1 can be set to 2.0 mm, and the overall height of the optical fiber cable 1 can be set to 6.0 mm. Further, as shown in FIG. 1, a notch 7 can be provided on the sheath 6 for the convenience of breaking the sheath 6 and taking out the internal 4-fiber ribbon 10 and the like. Since the sheath 6 has excellent flame retardancy and mechanical properties, it is molded using a flame retardant resin composition described later. The sheath 6 can be formed of a plurality of resin compositions to form a laminate composed of a plurality of layers. The molded body is preferably one layer because it is excellent in molding processability and can be manufactured at low cost. The flame-retardant optical fiber cable of the present invention can be produced by a conventional method such as extrusion molding or injection molding. Among these, the sheath is preferably manufactured by extrusion molding.

Hereinafter, each component of the flame-retardant resin composition (P) used as the sheath of the optical fiber cable of the present invention will be described.
The flame retardant resin composition comprises (a) an ethylene-α-olefin copolymer, (b) a polypropylene resin, and (c-1) a polyolefin resin modified with an unsaturated carboxylic acid or derivative thereof and / or (C-2) The metal hydrate (B) and (C) red phosphorus are contained with respect to the thermoplastic resin component (A) which consists of an ethylene- (meth) acrylic acid copolymer.
However, the flame retardant resin composition (P) does not contain a (meth) acrylate-based and / or acrylic crosslinking aid.

(A) Thermoplastic resin component (a) Ethylene-α-olefin copolymer The ethylene-α-olefin copolymer is preferably a copolymer of ethylene and an α-olefin having 4 to 12 carbon atoms. Specific examples thereof include 1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene, 1-decene, 1-dodecene and the like.
The ethylene-α-olefin copolymer includes LLDPE (linear low density polyethylene), LDPE (low density polyethylene), VLDPE (very low density polyethylene), EBR (ethylene-butadiene rubber), and a single site catalyst. And an ethylene-α-olefin copolymer synthesized in the above.
The density of the ethylene-α-olefin copolymer is preferably 940 kg / m ³ or less. If the density of the ethylene-α-olefin copolymer is in this range, even if it contains metal hydrates or red phosphorus, the mechanical properties and cold resistance are not significantly reduced, and the optical fiber core is pierced by the laying oviduct of Komazemi. Wire damage can be reduced. More preferably, it is 930 kg / m ³ or less, and particularly preferably 928 kg / m ³ or less. Within this range, even if a metal hydrate or red phosphorus is further contained, the mechanical strength and cold resistance are not significantly reduced, and the damage of the optical fiber core due to the puncture of the oviposition tube of the burdock can be reduced. Instead, the depth of the laying tube piercing the sheath itself can be reduced.
There is no restriction | limiting in particular in the minimum of the density of an ethylene-alpha-olefin copolymer. If the density is too low, the mechanical strength and flame retardancy are lowered, so the density of the ethylene-α-olefin copolymer is preferably 875 kg / m ³ or more.
The ethylene-α-olefin copolymer preferably has a melt flow rate (ASTM D-1238) of 0.5 to 30 g / 10 min.

As the ethylene-α-olefin copolymer in the present invention, those synthesized in the presence of a single site catalyst, linear low density polyethylene, ultra low density polyethylene, and the like can be preferably used. Among them, those synthesized in the presence of a single site catalyst are preferable, and the method described in JP-A-6-306121, JP-A-7-500622 and the like can be used as the production method.
By using an ethylene-α-olefin copolymer synthesized in the presence of a single site catalyst, even when metal hydrate is filled as a flame retardant, mechanical properties such as tensile strength, tearing speed, and impact strength are reduced. Can be reduced.

Single site catalysts have a single active point and high polymerization activity. The catalyst is also called a metallocene catalyst or a Kaminsky catalyst. The ethylene-α-olefin copolymer synthesized using the catalyst is characterized by a narrow molecular weight distribution and composition distribution.
Therefore, using an ethylene-α-olefin copolymer synthesized using a single site catalyst increases the melt viscosity compared to using an ethylene-α-olefin copolymer synthesized using a multisite catalyst. , The melt tension may decrease. For this reason, as an ethylene-α-olefin copolymer synthesized using a single site catalyst, long chain branching is introduced using an asymmetric catalyst as a single site catalyst (Constrained Geometry Catalytic Technology), or during synthesis. By connecting two polymerization tanks to make two peaks in the molecular weight distribution (Advanced Performance Thermopolymer), it is possible to use one having improved molding processability.
As the ethylene-α-olefin copolymer synthesized in the presence of the single site catalyst used in the present invention, those having improved moldability are preferred. For example, “AFFINITY” (trade name, manufactured by Dow Chemical), “ENGAGE” (trade name, manufactured by the company), “Kernel” (trade name, manufactured by Nippon Polyethylene), “Evolue” ( Product name, manufactured by Sumitomo Mitsui Polyolefin Co., Ltd.), and “Umerit” (trade name, manufactured by Ube Maruzen Polyethylene Co., Ltd.).
In the present invention, the content of the ethylene-α-olefin copolymer is 85 to 15% by mass in the thermoplastic resin component (A). More preferably, it is preferable that it is 70-30 mass%. By setting the blending amount of the ethylene-α-olefin copolymer within this range, even when a metal hydrate is blended, it has cold resistance and can maintain high mechanical properties such as tensile strength. it can. If the blending amount of the ethylene-α-olefin copolymer in the thermoplastic resin component (A) is too large, the mechanical strength is lowered, and if it is too little, the elongation is increased and the cold resistance is lowered.

(B) Polypropylene resin (b) As the polypropylene resin of the component, propylene homopolymer (homopolypropylene resin), ethylene-propylene random copolymer, ethylene-propylene block copolymer, copolymer of propylene and ethylenepropylene (TPO) or the like can be used.
Here, the ethylene-propylene random copolymer refers to those having an ethylene component content of about 1 to 5% by mass, and refers to those in which the ethylene component is randomly incorporated into the propylene chain. The ethylene-propylene block copolymer is one having an ethylene component content of about 5 to 15% by mass, wherein the ethylene component and the propylene component are present as independent components.
By blending the polypropylene resin, it is possible to reduce damage to the optical fiber core wire due to the puncture of the oviposition tube of the bear oak. Among polypropylene resins, a propylene homopolymer is preferable as the polypropylene resin of the component (b). By using the propylene homopolymer, not only can the damage of the optical fiber core wire caused by the puncture of the laying oviduct of Coomasemi be reduced, but also the depth of the laying of the laying tube into the sheath itself can be reduced.
The melt flow rate (ASTM-D-1238) of the polypropylene resin to be blended is preferably 0.1 to 60 g / 10 minutes, more preferably 0.1 to 25 g / 10 minutes, and still more preferably 0.3 to 15 g / 10 minutes. Within this range, the sheath can be produced without impairing the molding processability of the sheath. Moreover, the damage of the optical fiber core wire caused by the piercing of the oviposition tube of the komazemi can be reduced without impairing the mechanical strength and cold resistance.
Content of a polypropylene resin is 10-80 mass% in a thermoplastic resin component (A). If the content of the polypropylene resin is within this range, the optical fiber core wire by piercing the oviposition tube of Komazemi without significantly lowering the mechanical strength and cold resistance even if metal hydrate and red phosphorus are contained. Damage can be reduced. The content of the polypropylene resin is preferably 10 to 65% by mass, more preferably 10 to 60% by mass, and particularly preferably 10 to 50% by mass in the thermoplastic resin component (A). If the polypropylene resin content is too high, cold resistance and elongation will decrease, and if it is too low, the mechanical strength will decrease, and it will be difficult to reduce damage to the optical fiber due to the puncture of the oviposition tube of the komazemi. .

(C-1) Polyolefin resin modified with unsaturated carboxylic acid or derivative thereof, (c-2) Ethylene- (meth) acrylic acid copolymer “Unsaturated carboxylic acid or derivative thereof (hereinafter referred to as these”) The term “polyolefin resin modified with unsaturated carboxylic acid or the like” refers to a resin obtained by graft polymerization by modifying a polyolefin resin with an unsaturated carboxylic acid or a derivative thereof.
The modification of the polyolefin resin with an unsaturated carboxylic acid or the like can be performed, for example, by heating and kneading the polyolefin resin and the unsaturated carboxylic acid or the like in the presence of an organic peroxide.
Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid and the like. In addition, as derivatives of unsaturated carboxylic acid, acrylic acid ester, methacrylic acid ester, maleic acid monoester, maleic acid diester, maleic anhydride, itaconic acid monoester, itaconic acid diester, itaconic anhydride, fumaric acid monoester, Examples thereof include fumaric acid diester and fumaric anhydride.
Polyolefin resins include polyethylene (linear polyethylene, ultra-low density polyethylene, high density polyethylene), polypropylene resins (propylene homopolymer, propylene-ethylene random copolymer, propylene-ethylene block copolymer, propylene And other small amounts of α-olefins (eg, copolymers of 1-butene, 1-hexene, 4-methyl-1-pentene, etc.), copolymers of ethylene and α-olefins, ethylene-vinyl acetate Copolymers and ethylene- (meth) acrylic acid ester copolymers can be used.

  Further, as the polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, a styrene copolymer modified with an unsaturated carboxylic acid or a derivative thereof can be used. A styrene-based copolymer is a hydrogenated product of a copolymer mainly composed of an aromatic vinyl compound and a conjugated diene compound, and is a copolymer or random copolymer mainly composed of a block structure of a conjugated diene compound and an aromatic vinyl compound. It is a hydrogenated product of a copolymer mainly composed of a structure. By heating and kneading a styrene copolymer and an unsaturated carboxylic acid in the presence of an organic peroxide, the unsaturated carboxylic acid or the like can be grafted to the conjugated diene moiety. Therefore, in the present invention, the polyolefin resin modified with the unsaturated carboxylic acid or derivative thereof as the component (c-1) includes a styrene copolymer modified with the unsaturated carboxylic acid or derivative thereof. Shall.

Examples of the aromatic vinyl compound in the styrene copolymer include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-p-amino. There are ethyl styrene, vinyl toluene, p-tert-butyl styrene, etc., among which styrene is preferable.
Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, and one or more of these are selected. And combinations thereof are preferred.
Moreover, what hydrogenated at least 90% of the aliphatic double bond based on a conjugated diene compound is preferable.

  The modification of the polyolefin resin can be performed, for example, by heating and kneading the polyolefin resin and unsaturated carboxylic acid in the presence of an organic peroxide. The amount of modification with an unsaturated carboxylic acid or the like is preferably 0.5 to 15% by mass relative to the polyolefin resin. The modification of the styrene copolymer is preferably 0.5 to 15% by mass with respect to the conjugated diene monomer portion of the copolymer.

  Specific examples of polyolefins modified with unsaturated carboxylic acid include polybond (trade name, manufactured by Crompton Co., Ltd.), Adtex (trade name, manufactured by Nippon Polyethylene Co., Ltd.), Admer (trade name, Mitsui Chemicals Co., Ltd.), Clayton (trade name, manufactured by JSR Clayton Co., Ltd.) and the like.

Examples of the (c-2) ethylene- (meth) acrylic acid copolymer in the present invention include an ethylene-acrylic acid copolymer and an ethylene-methacrylic acid copolymer. Specifically, for example, Nukurel (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd.) can be mentioned.
In this invention, (c-1) component and / or (c-2) component may use any 1 type, and may use (c-1) component and (c-2) component together.
In the present invention, the component (c-1) and / or the component (c-2) is chemically bonded to a metal hydrate described below, particularly magnesium hydroxide, at the time of molding, so that the flame-retardant light of the present invention is used. The fiber cable can exhibit flame retardancy, mechanical properties, and wear resistance. The above-mentioned excellent effect is particularly remarkable when a polyolefin resin is modified with acrylic acid or methacrylic acid or an ethylene (meth) acrylic acid copolymer is used. Therefore, in the present invention, as the component (c-1) and / or (c-2), is a polyolefin resin modified with acrylic acid or methacrylic acid or an ethylene (meth) acrylic acid copolymer? It is preferable to use together.
In the present invention, the content of the component (c-1) and / or the component (c-2) is 0 to 20% by mass in the thermoplastic resin component (A). From the viewpoint of dispersibility and compatibility during material kneading, the content of the component (c-1) and / or the component (c-2) is 5 to 15% by mass in the thermoplastic resin component (A). Is preferred. By setting it within this range, the embrittlement temperature of the flame retardant resin composition (P) can be lowered, and the flame retardancy can be improved.
In particular, in order to reduce the puncture of the laying oviduct of Coomasemi to the sheath, the component (c-1) and / or the component (c-2) is 5 to 10% by mass in the thermoplastic resin component (A). Is preferred.

(B) Metal Hydrate Examples of the (B) metal hydrate in the flame retardant resin composition (P) used in the present invention include magnesium hydroxide and aluminum hydroxide. Magnesium hydroxide has a great effect of improving flame retardancy when blended into a flame retardant resin composition. Moreover, since the desorption temperature of crystal water in magnesium hydroxide is higher than that of other metal hydrates, it can be molded without foaming when extruded as a sheath. For this reason, as a metal hydrate mix | blended in the flame-retardant resin composition used for this invention, magnesium hydroxide is preferable.

In the present invention, commercially available magnesium hydroxide can be used. Magnesium hydroxide may be either not surface-treated or surface-treated. Examples of the surface treatment agent include fatty acids, phosphoric acid, titanates, and silane coupling agents. From the viewpoint of reactivity with the resin component (A), in the present invention, it is preferable to use a magnesium hydroxide surface-treated with a silane coupling agent. In this case, magnesium hydroxide that has not been surface-treated may be used in combination.
The silane coupling agent in the present invention is preferably one having a vinyl group, a methacryloxy group, a glycidyl group, or an amino group at the terminal. Specifically, for example, vinyltrimethoxysilane, vinyltriethoxysilane, glycidoxypropyltrimethoxysilane, glycidoxypropyltriethoxysilane, glycidoxypropylmethyldimethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropyl Triethoxysilane, methacryloxypropylmethyldimethoxysilane, mercaptopropyltrimethoxysilane, mercaptopropyltriethoxysilane, aminopropyltriethoxysilane, aminopropyltrimethoxysilane, N- (β-aminoethyl) -γ-aminopropyltripropyl Examples include methyldimethoxysilane and N- (β-aminoethyl) -γ-aminopropyltripropyltrimethoxysilane. Of these, vinyltrimethoxysilane, vinyltriethoxysilane, methacryloxypropyltriethoxysilane, methacryloxypropylmethyldimethoxysilane and the like are preferable.
As a surface treatment method using a silane coupling agent, the treatment can be performed by a commonly used method. For example, magnesium hydroxide that has been surface-treated by a method of dry blending and mixing a silane coupling agent in advance with magnesium hydroxide that has not been surface-treated, or a method of wet-treating a silane coupling agent with magnesium hydroxide. Can be obtained. Moreover, a flame retardant resin composition (P) can be obtained by blending a silane coupling agent during melting and kneading of the resin mixture. The amount of the silane coupling agent to be used is appropriately added in an amount sufficient for surface treatment. The content is specifically 0.1 to 2.5% by mass, preferably 0.2 to 1.8% by mass, more preferably 0.3 to 1.0% by mass with respect to magnesium hydroxide. .

Further, magnesium hydroxide that has already been treated with a silane coupling agent can also be used. Specific examples of magnesium hydroxide surface-treated with a silane coupling agent in advance include Kisuma 5L, Kisuma 5N, Kisuma 5P (all trade names, manufactured by Kyowa Chemical Co., Ltd.) and the like.
Examples of untreated magnesium hydroxide include Kisuma 5 (trade name, Kyowa Chemical Co., Ltd.), Magnifine H5 (trade name, Albemarle Corp.), and the like.
In the present invention, when magnesium hydroxide is treated with a silane coupling agent, any one silane coupling agent alone or two or more may be used in combination. Magnesium hydroxide that has not been surface-treated or magnesium hydroxide that has been surface-treated may be used alone or in combination. Magnesium hydroxide subjected to different surface treatments can be used in combination.

The compounding quantity of metal hydrates, such as magnesium hydroxide in this invention, is 10 mass parts or more and less than 50 mass parts with respect to 100 mass parts of thermoplastic resin components (A). The amount of the metal hydrate, the thermoplastic resin component (A) 100 parts by mass of to, preferably 15 to less than 50 parts by weight, more preferably 20 to less than 50 parts by weight.
If the blending amount of the metal hydrate is within this range, it can pass the 60-degree inclined combustion test specified in JIS C 3005, and can greatly reduce the stab scars caused by the oviposition tube of the koma-zemi.

The present inventors have observed in detail where the puncture of the oviposition tube of the bearfish occurs. As a result, it has been found that the stab damage of the envelope by the egg-laying tube is often due to peeling of the resin component and the metal hydrate in the sheath molded using the flame-retardant resin composition (P). Then, the flame-retardant resin composition which forms a sheath was studied earnestly. As a result, if the amount of the metal hydrate is within the above range, the metal hydrate and the entire resin component are finely dispersed in the nano-micro state, and the metal hydrate is integrated with the resin component. Thus, it was found that the rigidity, strength, and reinforcing properties inherent to metal hydrates are exhibited, and the puncture of the oviposition of the bear oak is significantly reduced. This effect can obtain a high effect especially in the case of magnesium hydroxide among metal hydrates. Moreover, flexibility and cold resistance can be ensured by the presence of component (b) having high crystallinity and component (a) having flexibility in a form compatible with component (b).
Further, by using the component (c-1) and / or the component (c-2) in combination, these components and magnesium hydroxide have strong ionic bonding properties, so these components are present in the vicinity of magnesium hydroxide. . As a result, it is considered that puncture damage to the oviposition tube of the courgenum is less likely to occur at the interface between the magnesium hydroxide and the resin component. Therefore, it is preferable to blend the component (c-1) and / or the component (c-2). In addition, the action of the component (c-1) and / or the component (c-2) and magnesium hydroxide remarkably appears when magnesium hydroxide whose surface is treated with a silane coupling agent is used. Accordingly, it is preferable to use magnesium hydroxide that has been surface-treated with a silane coupling agent.

(C) Red phosphorus In the flame-retardant resin composition used in the present invention, the flame-retardant composition (P) is used in order to maintain flame retardancy even if the amount of metal hydrate is reduced. Contains red phosphorus. As red phosphorus, a powdery material is preferably used because it is excellent in dispersibility and has good mechanical properties and flame retardancy when made into a flame retardant resin composition. In addition, red phosphorus is not treated untreated, but can be coated with an inorganic or organic coating. As red phosphorus used in the flame retardant resin composition of the present invention, red phosphorus having an average particle diameter of 3 to 9 μm can be preferably used.
The content of red phosphorus is 1 to 8 parts by mass with respect to 100 parts by mass of the thermoplastic resin (A). By setting it within this range, good mechanical strength, elongation, cold resistance and the like can be imparted while ensuring flame retardancy together with the metal hydrate. If the amount of red phosphorus is too small, the flame retardancy will be insufficient, and it will be necessary to add metal hydrate accordingly. As a result, it becomes difficult to reduce the damage of the optical fiber core wire caused by the puncture of the oviposition tube of the bearfish, and the mechanical strength, elongation, cold resistance and the like are lowered.

(D) Silicone compound In the flame-retardant resin composition (P) of the present invention, a silicone compound can be blended. Among the silicone compounds, those having a weight average molecular weight of 100,000 or more are preferable. More preferably, it is 100-800,000. The kinematic viscosity at 25 ° C. is preferably 10,000 cSt or more.
Here, the weight average molecular weight can be measured by GPC (gel permeation chromatograph) under the following conditions.
GPC device: HLC-8120GPC (trade name, manufactured by Tosoh Corporation)
Column: TSK gel SuperHM-H / H4000 / H3000 / H2000 (trade name, manufactured by Tosoh Corporation)
Flow rate: 0.6 ml / min,
Concentration: 0.3% by mass
Injection volume: 20 μl,
Column temperature: 40 ° C
The kinematic viscosity is a value obtained by measuring the viscosity with a rotational viscometer at 25 ° C. and then converting the kinematic viscosity.

By blending a silicone compound, the flame retardant resin composition (P) of the present invention does not impair flexibility even when blended with a metal hydrate or red phosphorus. It is possible to ensure the work of removing the outer cover.
Examples of the silicone compound include silicone oils having a normal linear siloxane structure, silicone rubbers mainly composed of polydiorganosiloxane, silicone resins and silicone gums which are the main raw materials for silicone rubber.
Among these, silicone gum is preferable. Examples of the basic structure of silicone gum include those having a methyl group, a vinyl group, or a phenyl group in the side chain of siloxane. Furthermore, in addition to these functional groups, other alkyl groups, alkenyl groups, or aromatic groups may be included. The thermoplastic resin component (A) of the present invention is blended with a silicone gum together with the metal hydrate (B) and red phosphorus (C), melt-kneaded, and the flame retardant resin composition (P) of the present invention. Can be obtained. At this time, the silicone gum is relatively easily compatible with each resin component and metal hydrate in the thermoplastic resin component (A), and flame retardancy with greatly improved surface smoothness as well as trauma resistance. A resin composition can be obtained. As a result, it is possible to further improve the lineability into the pipeline and the outer cover removal workability of the terminal.

(E) Other components The optical fiber cable of the present invention is installed outdoors. Therefore, in order to maintain high weather resistance, the flame retardant composition (P) can contain carbon. The carbon content is preferably 0 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic resin (A). If this amount is too large, the mechanical properties deteriorate.

The flame retardant composition (P) used in the present invention may be blended with at least one selected from zinc stannate, zinc hydroxystannate and zinc borate as necessary to further improve the flame retardancy. Is possible.
Zinc borate, zinc hydroxystannate, and zinc stannate used in the present invention preferably have an average particle size of 5 μm or less, more preferably 3 μm or less.
As zinc borate which can be used in the present invention, specifically, for example, alk Nex _{FRC-500 (2ZnO / 3B 2} O 3 · 3.5H 2 O), FRC-600 ( trade names, manufactured by Mizusawa Chemical ( Etc.). Examples of zinc stannate (ZnSnO ₃ ) and zinc hydroxystannate (ZnSn (OH) ₆ ) include Alkanex ZS and Alkanex ZHS (both trade names, manufactured by Mizusawa Chemical Co., Ltd.).
In the present invention, the content of zinc borate, zinc stannate or zinc hydroxystannate is preferably 2 to 20 parts by mass and more preferably 3 to 20 parts by mass with respect to 100 parts by mass of the thermoplastic resin (A). preferable. If the amount is too small, the effect of improving flame retardancy will not be exhibited. If the amount is too large, the mechanical strength, particularly the elongation will be reduced, and the appearance of an optical fiber cable will be deteriorated.

The flame retardant composition (P) used in the present invention includes various commonly used additives such as antioxidants, metal deactivators, flame retardants (auxiliaries), fillers, and lubricants. Etc. can be appropriately contained within a range not impairing the object of the present invention.
Examples of the antioxidant include amine-based oxidation such as a polymer of 4,4′-dioctyl diphenylamine, N, N′-diphenyl-p-phenylenediamine, and 2,2,4-trimethyl-1,2-dihydroquinoline. Inhibitor, pentaerythrityl-tetrakis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate), octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) Phenol-based antioxidants such as propionate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, bis (2-methyl-4- (3-n-alkylthiopropionyloxy) -5-tert-butylphenyl) sulfide, 2-mercaptobenzimidazole and its zinc salt, pentae Suritoru - tetrakis (3-lauryl - thiopropionate) and the like sulfur-based antioxidant such.
Examples of metal deactivators include N, N′-bis (3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyl) hydrazine, 3- (N-salicyloyl) amino-1,2,4. -Triazole, 2,2'-oxamidobis- (ethyl 3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate) and the like.
Other flame retardant (auxiliary) agents and fillers include clay, zinc oxide, tin oxide, titanium oxide, magnesium oxide, molybdenum oxide, antimony trioxide, silicone compounds, quartz, talc, calcium carbonate, magnesium carbonate, white For example, carbon.
Examples of the lubricant include hydrocarbons, fatty acids, fatty acid amides, esters, alcohols, and metal soaps. Among them, the inside of wax E, wax OP (both trade names, manufactured by Hoechst), etc. Examples include ester-based, alcohol-based, and metal soap-based materials that exhibit both lubricity and external lubricity.
As other compounding agents, plasticizers and additives may be added.

  The flame-retardant resin composition used in the optical fiber cable of the present invention can be obtained by melt-kneading the above-described components with a commonly used kneading apparatus such as a twin-screw kneading extruder, a Banbury mixer, a kneader, or a roll. it can.

EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these.
In addition, “part” indicating the composition indicates part by mass unless otherwise specified.

(Examples and comparative examples)
Table 1 shows the content of each component of the resin compositions of Examples and Table 2 of Comparative Examples.
First, each component shown in the following Tables 1 and 2 was dry blended at room temperature (23 ± 2 ° C.), and melt-kneaded using a Banbury mixer to produce each flame-retardant resin composition.
Next, as shown in FIG. 1, on the four-core tape core wire 2, the support wire 4 made of φ1.2 mm steel wire, and the two tension members 3, 3 ′ made of φ0.5 mm aramid FRP, An optical fiber cable was manufactured by extrusion coating the melt-kneaded flame retardant resin composition. As shown in FIG. 1, the length of the long side of the sheath excluding the support line 4 is 3.8 mm, the length of the short side is 2.0 mm, the length of the neck is 0.2 mm, and the thickness is 0.2 mm. It was. The outer diameter of the sheath covering the support wire 4 was 2.0 mm, and the total height of the optical fiber cable was 6.0 mm. The distance between the bottom of the V-shaped groove formed at the center of the cable portion and the optical fiber core wire was 0.45 mm.
Each of the obtained optical fiber cables was subjected to the following tests and evaluations, and the obtained results are shown in Table 1 and Table 2, respectively.

(1) Shore D hardness Type D durometer hardness (Shore D hardness) based on JIS K 7215 was measured using a sheet obtained by heating and pressing a flame-retardant resin. In order to make it difficult for burrowing to puncture the oviduct, a Shore D hardness of 57 or higher was accepted.

(2) Tensile test A flame-retardant resin composition was heat-press molded to produce a sheet having a thickness of 1.0 mm ± 0.15 mm. A dumbbell No. 2 type test piece based on JIS K 7113 was produced from this sheet and subjected to a tensile test. The test was conducted at 25 mm between marked lines and at a tensile speed of 200 mm / min. TS and YS in Tables 1 and 2 indicate tensile strength and yield strength, respectively. Those having both values of 15 MPa or more and elongation of 300% or more were regarded as acceptable.

(3) Cold resistance test The flame-retardant resin composition was heat-press molded to produce a sheet having a thickness of 2.0 mm. A test piece having a length of 38.0 mm ± 2.0 mm, a width of 6.0 mm ± 0.4 mm, and a thickness of 2.0 ± 0.2 mm was produced from this sheet. When this test piece was hit by a cold resistance test of JIS C 3005, a test piece having a temperature at which cracks occurred in the test piece was −30 ° C. or lower was regarded as acceptable.

(4) Flame retardancy test A 60-degree inclined combustion test based on JIS C 3005 was performed. After supporting the sample with a length of 300 mm collected from the finished product by inclining 60 degrees with respect to the horizontal, applying the tip of the reducing flame to the position 20 mm from the lower end of the sample until burning, and gently removing the flame The thing that self-extinguishes was accepted.

(5) Cicada oviduct piercing test The following tests were performed on the obtained optical fiber cable. One pair of two optical fiber cables cut to a length of 13 cm, and a total of 20 sets and 40 pieces are left in a cylindrical container with a height of 9 cm and a diameter of 9 cm together with the oats in the spawning season, and one day passes for each set. Then, the sheath of the part where the trace of the hole due to the spawning tube of the bearfish left on the optical fiber cable was removed, and the average value of the spawning wound depth and the presence or absence of damage of the optical fiber core wire were measured. There is no damage to the optical fiber core, but the case where the average value of the spawning wound depth exceeds 0.200 mm in the sheath is “◯”, the optical fiber core wire is not damaged, and the average spawning wound depth is in the sheath Those having a diameter of 0.200 mm or less were evaluated as “◎” as having excellent cicada oviposition piercing property. “◯” and “◎” were accepted, and those with damaged optical fiber cores were rejected, and “x” was assigned.

(6) Dynamic friction coefficient measurement test Based on JIS K 7125, the dynamic friction coefficient was measured. As a thing excellent about the wire-lineability to a pipe line, and the removal operation | work of the terminal jacket of a cable part, a dynamic friction coefficient needs 0.5 or less. If the coefficient of dynamic friction is 0.3 or less, it is extremely excellent with respect to the lineability to the pipe line and the work for removing the outer jacket of the cable portion. For this reason, the case where the dynamic friction coefficient was 0.5 or less was determined to be acceptable.

In addition, as each component, the following were used.
(01) Ethylene-α-olefin copolymer (component (a))
Polyethylene synthesized with metallocene catalyst Product name: Umerit 2525F (manufactured by Ube Maruzen Polyethylene)
(Density: 926 kg / m ³ )
(02) Ethylene-α-olefin copolymer (component (a))
Polyethylene synthesized with metallocene catalyst Product name: Umerit 1540F (manufactured by Ube Maruzen Polyethylene)
(Density: 913 kg / m ³ )
(03) Ethylene-α-olefin copolymer (component (a))
Polyethylene synthesized with metallocene catalyst Product name: Umerit 4040F (manufactured by Ube Maruzen Polyethylene)
(Density: 937 kg / m ³ )

(04) Polypropylene (component (b))
Block-propylene Product name: E-150GK (manufactured by Prime Polymer Co., Ltd.)
(05) Polypropylene (component (b))
Propylene homopolymer Product name: EA9 (Nippon Polypropylene Co., Ltd.)

(06) Polyolefin resin modified with unsaturated carboxylic acid (component (c-1))
Maleic acid-modified polyethylene Product name: L-6100M (manufactured by Nippon Polyethylene Co., Ltd.)
(07) Ethylene- (meth) acrylic acid copolymer (component (c-2))
Ethylene-methacrylic acid copolymer Product name: Nucrel 1207C

(08) Red phosphorus Product name: Hishiguard LP-F (manufactured by Nippon Chemical Industry Co., Ltd.)
(09) Untreated magnesium hydroxide (component (B))
Product name: Kisuma 5 (Kyowa Chemical Co., Ltd.)
(10) Silane-treated magnesium hydroxide (component (B))
Product name: Kisuma 5L (manufactured by Kyowa Chemical Co., Ltd.)
(11) Fatty acid-treated magnesium hydroxide (component (B))
Product name: Kisuma 5A (manufactured by Kyowa Chemical Co., Ltd.)
(12) Fatty acid-treated magnesium hydroxide (component (B))
Product Name: Magsees N-4
(13) Magnesium hydroxide surface-treated with a silane coupling agent (component (B))
Product Name: Magsees S-4

(14) Silicone compound Product name: CF9150 (manufactured by Toray Dow Corning Co., Ltd.)
(Weight average molecular weight: 100,000 or more, kinematic viscosity at 25 ° C .: 1 million cSt)
(15) Silicone compound Product name: X-22-2147 (manufactured by Shin-Etsu Chemical Co., Ltd.) (a masterbatch comprising 50% by mass of a silicone compound and 50% by mass of low-density polyethylene)
Degree of polymerization of silicone compound alone not containing low-density polyethylene: 5400 to 11000, weight average molecular weight: 400,000 to 800,000 (16) Oleic acid amide Product name: Armoslip CP (manufactured by Lion Akzo Co., Ltd.)
(17) Carbon black Product name: XC-72 (manufactured by Cabot Japan)

Here, the weight average molecular weight and viscosity of the silicone compounds of (14) and (15) are values measured by the following method.
(Weight average molecular weight)
It measured by GPC (gel permeation chromatograph) of the following conditions.
GPC device: HLC-8120GPC (trade name, manufactured by Tosoh Corporation)
Column: TSK gel SuperHM-H / H4000 / H3000 / H2000 (trade name, manufactured by Tosoh Corporation)
Flow rate: 0.6 ml / min,
Concentration: 0.3% by mass
Injection volume: 20 μl,
Column temperature: 40 ° C
(Kinematic viscosity)
The viscosity was measured with a rotational viscometer at 25 ° C. and then converted to kinematic viscosity.

  Tables 1 and 2 show the blending amounts of each material and the evaluation results.

As can be seen from Tables 1 and 2, the optical fiber cables of Comparative Examples 1 and 4 in which the component (a) of the optical fiber cable of the present invention was not blended lacked flexibility and failed in cold resistance. The optical fiber cables of Comparative Examples 2 and 5 not blended with the component (b) failed to be damaged by the puncture of the semi-vibrating tube. Further, Comparative Example 3 in which red phosphorus was not blended failed in flame retardancy.
On the other hand, the optical fiber cables of Examples 1 to 9 passed all of Shore D hardness, tensile properties, cold resistance, flame resistance, and semi-laying tube piercing properties. In particular, the optical fiber cables of Examples 1 to 9 had no damage to the optical fiber core wire in the semi-laying tube piercing test, and the average value of the depth of spawning wound on the sheath was 0.200 mm or less. Further, in Examples 2 to 8 , the dynamic friction coefficient was 0.3 or less.

DESCRIPTION OF SYMBOLS 1 Optical fiber cable of this invention 2 4 optical fiber core wire 3 Tension member 4 Support wire 5 Neck part 6 Sheath 7 Notch

Claims (7)

An optical fiber core wire having a coating formed on the outer periphery using an ultraviolet curable resin composition, and a tension member arranged in parallel in the longitudinal direction of the optical fiber core wire,
(A) an ethylene-α-olefin copolymer 85 to 15% by mass, (b) a polypropylene resin 10 to 80% by mass, and (c-1) a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, and / Or (c-2) 10 to 50 parts by mass of (B) metal hydrate with respect to 100 parts by mass of thermoplastic resin component (A) composed of 0 to 20% by mass of ethylene- (meth) acrylic acid copolymer. part below and (C) red phosphorus 1-8 parts by weight flame-retardant resin composition containing a (P) (where the flame retardant resin composition (P) is (meth) acrylate and / or acrylic crosslinked With no auxiliary)
The flame retardant optical fiber cable, wherein the optical fiber core wire and the tension member are covered. An optical fiber core wire having a coating formed on the outer periphery using an ultraviolet curable resin composition, and a tension member arranged in parallel in the longitudinal direction of the optical fiber core wire,
(A) an ethylene-α-olefin copolymer 85 to 15% by mass, (b) a polypropylene resin 10 to 80% by mass, and (c-1) a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, and / Or (c-2) 10 to 30 parts by mass of (B) metal hydrate and 100 parts by mass of the thermoplastic resin component (A) composed of 0 to 20% by mass of ethylene- (meth) acrylic acid copolymer and (C) Flame retardant resin composition (P) containing 1 to 8 parts by weight of red phosphorus (However, the flame retardant resin composition (P) is a (meth) acrylate-based and / or acrylic-based crosslinking aid). Not included)
The flame retardant optical fiber cable, wherein the optical fiber core wire and the tension member are covered. 3. The difficulty according to claim 1, wherein the flame retardant resin composition (P) contains 0.5 to 4 parts by mass of a silicone compound with respect to 100 parts by mass of the thermoplastic resin component (A). Flammable fiber optic cable. The flame-retardant optical fiber cable according to any one of claims 1 to 3, wherein the density of the (a) ethylene-α-olefin copolymer is 940 kg / m ³ or less. The flame-retardant optical fiber cable according to any one of claims 1 to 4 , wherein the (b) polypropylene resin is a propylene homopolymer. The difficulty according to any one of claims 1 to 5 , wherein the metal hydrate is untreated magnesium hydroxide and / or magnesium hydroxide whose surface is treated with a silane coupling agent. Flammable fiber optic cable. The flame-retardant optical fiber cable according to any one of claims 1 to 6 , wherein the molded body using the flame-retardant resin composition (P) is composed of one layer.

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