JP5478754B2 - Fiber optic cable - Google Patents

Description

  The present invention relates to a subscriber optical fiber cable.

  The optical fiber cable for the subscriber includes an optical drop cable drawn from the access system optical fiber cable to the subscriber's house, and an optical indoor cable used in the subscriber's house and a premises such as a building or a condominium. When laying cables in the premises of subscribers and buildings or condominiums, due to problems in appearance, the resin used for the cable jacket should be white, gray, brown, or other non-black outer wall. A suitable color is required. Further, from the viewpoint of protecting the global environment, a non-halogen flame retardant outer cover is used.

  Further, in laying and maintaining the optical fiber cable, a core wire comparison for specifying the core wire to be worked is performed. If the jacket of the cable is non-black, it is possible to confirm the leaked light from the jacket by bending the cable, to compare any core wire, and to detect the fault point. On the other hand, if the jacket of the cable is made black, not only the appearance is impaired, but also the contrast of the cords is impossible.

  When the color of the resin used for the jacket of the optical fiber cable is made non-black, which does not impair the beauty of the building such as gray or brown, the kind and amount of the flame retardant added to the resin is limited. Red phosphorus provides a synergistic effect on flame retardancy when used in combination with magnesium hydroxide. However, when red phosphorus is added to the flame retardant, the color becomes dark red and it becomes difficult to obtain a desired color. In order to suppress the dark red color peculiar to red phosphorus, a treatment method for coating the surface of red phosphorus with a modified film has been proposed (see Patent Document 1). However, the treatment of the red phosphorus surface is not easy, and there is a problem that the manufacturing cost is greatly increased.

  When red phosphorus is not blended, a flame retardant resin to which magnesium hydroxide or magnesium hydroxide and a nitrogen compound are added as a flame retardant is used. In this case, a large amount of flame retardant is required to obtain a desired flame retardant name. A resin to which a large amount of a flame retardant is added significantly reduces mechanical properties such as tensile strength and cold resistance. Therefore, there is a problem that it cannot be used outdoors in a cold region.

  In addition, so-called intensive flame retardants mainly composed of phosphorous nitrogen compounds such as melamine polyphosphate have high efficiency with respect to flame retardancy and can reduce the amount added to the resin. . As a result, it is possible to obtain a white resin that satisfies the mechanical properties and flame retardancy required for the jacket. However, a resin to which an intomesent flame retardant is added has a problem in water resistance, and there is a problem that the flame retardant bleeds out when used outdoors.

  Thus, in order to satisfy the flame retardancy, mechanical properties, cold resistance, and weather resistance, it is desirable that red phosphorus is added as a flame retardant to the resin used for the jacket. However, when red phosphorus is used, the color of the resin tends to be red, and it is difficult to realize a non-black color.

Japanese Patent No. 3935012

  In view of the above problems, an object of the present invention is to provide an optical fiber cable having a color that can maintain the aesthetics of a building and can be contrasted with a core while maintaining flame retardancy, mechanical properties, cold resistance and weather resistance. It is to provide.

According to one aspect of the present invention, an optical fiber core, a tensile body disposed in parallel with the optical fiber core, and a jacket covering the optical fiber core and the tensile body, the jacket is provided. A polyolefin resin containing magnesium hydroxide, red phosphorus, carbon and titanium oxide. Magnesium hydroxide is in a range of 65 parts by weight to 125 parts by weight and red phosphorus is 10 parts by weight with respect to 100 parts by weight of the polyolefin resin. An optical fiber cable containing 25 parts by weight or less, carbon in a range of 0.02% by weight or more and 0.249 % by weight or less, and titanium oxide in a range of 3 parts by weight or more and 10 parts by weight or less is provided. The

  According to the present invention, it is possible to provide an optical fiber cable having a color capable of maintaining the aesthetics of a building and capable of contrasting core wires while maintaining flame retardancy, mechanical properties, cold resistance and weather resistance. Become.

It is sectional drawing which shows an example of the optical fiber cable which concerns on embodiment of this invention. It is sectional drawing which shows the other example of the optical fiber cable which concerns on embodiment of this invention. It is a table | surface which shows an example of the mixing | blending of a resin used for the jacket of the optical fiber cable which concerns on embodiment of this invention, and a test result. It is a table | surface which shows the test method and criterion of the test item shown in FIG. It is a table | surface which shows the brown color of resin used for the jacket of the optical fiber cable which concerns on embodiment of this invention. It is a table | surface which shows an example of the mixing | blending of a resin used for the brown-type jacket of the optical fiber cable which concerns on embodiment of this invention, and a test result. It is a table | surface which shows an example of the mixing | blending of a resin used for the gray-type jacket of the optical fiber cable which concerns on embodiment of this invention, and a test result. It is a table | surface which shows the test method and criterion of the test item shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

  The following embodiments of the present invention exemplify apparatuses and methods for embodying the technical idea of the present invention. The technical idea of the present invention is based on the material and shape of component parts. The structure, arrangement, etc. are not specified below. The technical idea of the present invention can be variously modified within the technical scope described in the claims.

  The optical fiber cable according to the embodiment of the present invention is the optical indoor cable 1 used for the indoor wiring of the subscriber's house shown in FIG. 1, the optical drop cable 2 drawn from the trunk cable to the subscriber's house shown in FIG. . As shown in FIG. 1, the optical indoor cable 1 includes an optical fiber core wire 10, a strength member 12, and a jacket 14. The strength members 12 are arranged in parallel on both sides of the optical fiber core wire 10. The outer jacket 14 collectively covers the optical fiber core wire 10 and the tensile body 12. A pair of notches 16 are provided on the outer edge of the jacket 14 so as to face each other with the optical fiber core wire 10 interposed therebetween.

  As shown in FIG. 2, the optical drop cable 2 includes a cable portion 4, a support wire portion 6, and a connection portion 8 that connects the cable portion 4 and the support wire portion 6. The cable portion 4 includes an optical fiber core wire 10 and a strength member 12. The support line portion 6 includes a support line 18. The support wire 18 is disposed in parallel to the optical fiber core wire 10 and the strength member 12. The optical fiber core wire 10, the strength member 12, and the support wire 18 are collectively covered with the outer jacket 14. A pair of notches 16 are provided on the outer edge of the jacket 14 so as to face each other with the optical fiber core wire 10 interposed therebetween.

  The outer shape of the cable portion 4 of the optical indoor cable 1 and the optical drop cable 2 is, for example, a rounded rectangle. However, the shapes of the optical indoor cable 1 and the cable portion 4 are not limited, and may be, for example, oval, circular, or elliptical.

  Although the single-core type core wire is used as the optical fiber core wire 10, a plurality of core wires, for example, a four-core tape type core wire may be used. As the strength member 12, a pair of strength members 12 facing each other with the optical fiber core wire 10 interposed therebetween is used, but a single strength member may be used. As the strength member 12, a steel wire or fiber reinforced plastic (FRP) is used. A steel wire is used as the support wire 18.

  The resin used for the outer jacket 14 is required to have characteristics such as mechanical characteristics, flame retardancy, and weather resistance. In addition, since the optical indoor cable 1 and the optical drop cable 2 are installed in the subscriber's house, the outer wall of the subscriber's house, and the like, the outer cover 14 has a white, gray, or brown color that does not impair the appearance. Is required. For example, as a main raw material of the outer jacket 14, polyethylene (PE), polypropylene (PP), ethylene ethyl acrylate copolymer (EEA), ethylene vinyl acetate copolymer (EVA), ethylene propylene copolymer (EP), etc. Polyolefin (PO) resin is used. Additives such as flame retardants, weathering agents, and coloring agents are added to the outer jacket 14.

(Brown jacket)
3 is a polyolefin resin in which EEA (Mitsui / DuPont Polychemical, Everflex EEA, A-701) and linear low density polyethylene (LLDPE) (Nippon Polyethylene, Novatec LL, UE320) are mixed. The characteristics of a cable jacket made experimentally using a resin with various additives added as a main raw material. As additives, magnesium hydroxide (Kyowa Chemical Industry, Kisuma 5E), red phosphorus (Rin Chemical Industry Co., Ltd., Nobaret 120UF), antioxidant (Ciba Specialty Chemicals, IRGANOX 1076), weathering agent (Ciba Specialty Chemicals, TINUVIN 326), carbon (manufactured by Cabot, VULCAN9A32), titanium oxide (manufactured by Titanium Industry Co., Ltd., KR-380N) and the like are used. In the table of FIG. 3, ◎, ○, and NG indicate that they are excellent, good, and impossible, respectively.

  Further, the table of FIG. 4 shows the test method and determination criteria for each test item shown in FIG. The table of FIG. 5 shows notation by three attributes of hue, brightness, and saturation of the Munsell color system, and notation by blue, red, yellow, and black (CMYK) for various color names corresponding to the brown color.

  As shown in FIG. 3, the resin A is a compound used for a black jacket for a general optical drop cable. Resins B, C, D, and E are blended for the purpose of non-black white or brown color.

  Resin A has 65 parts by weight of magnesium hydroxide, 5 parts by weight of red phosphorus, 0.15 parts by weight of antioxidant, and 1.5 parts by weight of carbon with respect to 70 parts by weight of EEA and 30 parts by weight of LLDPE. 7% by weight is added. The added carbon functions as a black colorant, a weather resistance imparting agent, and a reinforcing material. When the resin A is used, the properties required for the cable jacket such as strength, flame retardancy, and weather resistance can be satisfied. However, since carbon is added, it becomes a black jacket.

  Resin C is a blend in which 0.2 parts by weight of a weathering agent is added to resin A without adding carbon. Although resin C is non-black, it becomes a deep red color that is difficult to maintain its aesthetic appearance, and the weather resistance is also deteriorated.

  Resin E further eliminates the addition of red phosphorus and adds 0.2 parts by weight of titanium oxide. Titanium oxide is a white colorant and provides weather resistance. By adding titanium oxide, the resin E becomes white, but the weather resistance is not improved. Further, in the resin E, the oxygen index is lowered to 28, and the flame retardancy is deteriorated.

  Resin B is a blend in which the amount of magnesium hydroxide added to resin E is increased from 65 parts by weight to 150 parts by weight. With the increase in magnesium hydroxide, the resin B has the same oxygen index as that of the resin A, and flame retardancy is improved. However, in addition to poor weather resistance, cold resistance also deteriorates.

  Resin D is a blend in which 3 parts by weight of titanium oxide is added to resin C. By using red phosphorus and titanium oxide that gives a white coloring effect, the resin D turns brown. Further, weather resistance is improved by increasing the amount of titanium oxide as compared with resins B and E. Thus, without adding carbon, by adding titanium oxide, the deterioration of strength, flame retardancy, and weather resistance can be prevented, and a brown envelope that can maintain the aesthetics of the building is realized. be able to. The same effect can be obtained even if 3 parts by weight or more of titanium oxide is blended. However, since titanium oxide is expensive, it is not desirable in terms of production cost to add more than 10 parts by weight.

  The table of FIG. 6 shows the characteristics of the cable jacket using a resin having a composition in which the addition amounts of magnesium hydroxide and red phosphorus are changed based on the resin D shown in FIG. As for red phosphorus, the amount of magnesium hydroxide added is 65 parts by weight, and is changed in the range of 2 to 12 parts by weight. With respect to magnesium hydroxide, the amount of red phosphorus added is 11 parts by weight, and is varied in the range of 65 parts by weight to 150 parts by weight. In addition, 3 parts by weight of titanium yellow (Pigment Inc., Pigment Yellow 53) and 1 part by weight of a petite are blended as a colorant for toning the brown color. In the table of FIG. 6, ◎, ○, and NG indicate that they are excellent, good, and impossible, respectively.

  As shown in the table of FIG. 6, the resin D-1 obtained by adding a petal and titanium yellow to the resin D shown in the table of FIG. 3 satisfies all the characteristics such as color, flame retardancy, and cold resistance. ing. In the resin D-2 in which the addition amount of magnesium hydroxide is reduced to 60 parts by weight and the addition amount of red phosphorus is reduced to 3 parts by weight, the flame retardancy is poor. Further, even with the resin D-3 in which the amount of red phosphorus added is reduced to 2 parts by weight, the flame retardancy is poor.

  Resin D-4 and D-5 are added to 6 parts by weight and 11 parts by weight of red phosphorus, and all the properties such as color, flame retardancy and cold resistance are satisfied. In the resin D6 in which the amount of red phosphorus added is further increased to 12 parts by weight, the resin becomes red and the color becomes poor. In addition, resin D-7 in which the amount of red phosphorus added is 11 parts by weight as in resin D-5 and the amount of magnesium hydroxide added is increased to 150 parts by weight has poor cold resistance. Resin D-8 with 11 parts by weight of red phosphorus and 100 parts by weight of magnesium hydroxide satisfies all the characteristics such as color, flame retardancy, and cold resistance.

  Thus, the amount of red phosphorus added is preferably in the range of 5 parts by weight to 11 parts by weight. The amount of magnesium hydroxide added is desirably in the range of 65 to 100 parts by weight.

  In the optical fiber cable according to the embodiment, a polyolefin resin containing magnesium hydroxide, red phosphorus, and titanium oxide is used as the jacket 14. Contains 100 parts by weight of magnesium hydroxide in a range of 65 parts by weight or more and 100 parts by weight or less, red phosphorus in a range of 3 parts by weight or more and 11 parts by weight or less, and 3 parts by weight of titanium oxide. Formulate as follows. As a result, the outer jacket 14 becomes brown, can maintain the aesthetics of buildings, etc., and can suppress deterioration of characteristics required for the outer jacket 14 such as mechanical strength, flame retardancy, and weather resistance. . Further, as the outer cover 14, in addition to magnesium hydroxide, red phosphorus, and titanium oxide, a colorant such as a petite and titanium yellow is adjusted to adjust the brown color tone shown in FIG. Color is possible.

  Moreover, as shown in the table | surface of FIG. 6, each of resin D-1 to D-8 has the lightness of the Munsell color system 7.7-8. By bending the optical fiber cable, it is possible to easily check the leaked light from the jacket 14. For the cord control, light with a wavelength of 1.55 μm is conducted to the optical fiber cable at an input level of about −20 dBm, and leakage light is confirmed. As a result, for all the resins D-1 to D-8, the binding efficiency was less than 40 dB, and excellent cord contrast was confirmed. In addition, as for the cord contrast, it has been confirmed that the coupling efficiency is less than 60 dB when the brightness of the outer jacket is 4.9 or more.

  In addition, as a polyolefin resin, EEA and LLDPE are used in combination. EEA has strong cold resistance, but it has low heat resistance when used alone, and EEA melts when the temperature of EEA rises under sunlight. Further, EEA originally has a low tensile strength and is easily broken by a strong tensile tension or the like. On the other hand, LLDPE alone has a higher degree of crystallinity in the resin than EEA, so the amount of additive accepted is small, and a large amount of flame retardant cannot be blended. Thus, it is desirable to blend EEA and LLDPE in an appropriate balance, for example, in the range of 60 parts by weight to 40 parts by weight to 20 parts by weight.

(Gray jacket)
The table of FIG. 7 shows the composition and characteristics of the experimentally produced resins 1 to 18 as the resin used for the gray outer jacket 14. As shown in the table of FIG. 7, EEA (Mitsui / DuPont Polychemicals, Everflex EEA, A-703) and linear low density polyethylene (LLDPE) (Nippon Polyethylene, Novatec LL, UE320) are mixed. Various additives are added using the polyolefin resin as a main raw material. As additives, magnesium hydroxide (Kyowa Chemical Industry, Kisuma 5E), red phosphorus (Rin Chemical Industry Co., Ltd., Nobaret 120UF), antioxidant (Ciba Specialty Chemicals, IRGANOX 1076), weathering agent (Ciba Specialty Chemicals, TINUVIN 326), carbon (manufactured by Cabot, VULCAN9A32), titanium oxide (manufactured by Titanium Industry Co., Ltd., KR-380N) and the like are used.

  In the table of FIG. 7, the blending of each additive other than carbon is shown in parts by weight with respect to 100 parts by weight of polyolefin resin in which 70 parts by weight of EEA and 30 parts by weight of LLDPE are mixed. The addition amount of magnesium hydroxide, red phosphorus, carbon, and titanium oxide is changed. Antioxidants and weathering agents are added in a certain number of parts in all the resins 1 to 18. In the table of FIG. 7, ◎, ○, Δ, and NG indicate that they are excellent, good, acceptable, and impossible, respectively.

  In addition, the table of FIG. 8 shows test methods and determination criteria for test items for evaluating each characteristic shown in FIG. With regard to the color, the aim is to make it gray by diluting the color of red phosphorus close to white by the decoloring effect of titanium oxide and adding a small amount of carbon. Here, as shown in FIG. 8, if the lightness is 3 or more and 8 or less and the saturation is 0 or more and 1.5 or less in the Munsell color system, it is recognized as gray.

  Regarding the color tone, as shown in FIG. 7, in the resin 3 of 1 part by weight of titanium oxide, the resin 7 of 0% by weight of carbon, and the resin 14 of 30 parts by weight of red phosphorus, red phosphorus is strongly reddish and gray Not recognized. In particular, the resin 3 is rosy because there is no decoloring effect of titanium oxide. Thus, to obtain a gray color, it is necessary to blend 25 parts by weight or less of red phosphorus, 0.018% by weight or more of carbon, and 3 parts by weight or more of titanium oxide.

  In the case of resin 1 with 60 parts by weight of magnesium hydroxide and resin 2 with 5 parts by weight of red phosphorus, flame retardancy is not possible. In order to satisfy the flame retardancy, it is necessary to blend 65 parts by weight or more of magnesium hydroxide and 10 parts by weight or more of red phosphorus as a flame retardant. Self-extinguishing can be considered due to the synergistic effect of magnesium hydroxide and red phosphorus. Moreover, in the resin 15 to the resin 18 in which magnesium hydroxide is 80 parts by weight or more, the flame retardancy is further improved.

  The resin 3 having 0.028% by weight of carbon and 1 part by weight of titanium oxide has poor weather resistance. In order to satisfy the weather resistance, it is necessary to blend 3 parts by weight or more of titanium oxide. Further, when 0.2% by weight or more of carbon is blended, the weather resistance is further improved. Since both carbon and titanium oxide have a light shielding effect, particularly ultraviolet light, they function to protect the resin. Since titanium oxide is expensive, adding more than 10 parts by weight is not desirable in terms of manufacturing cost.

  For the cord control, light with a wavelength of 1.55 μm is conducted to the optical fiber cable at an input level of about −20 dBm, and leakage light is confirmed. As shown in the table of FIG. 7, when the blending of carbon increases, the light shielding effect by carbon becomes remarkable, and the brightness decreases. In the resin 13 having 0.306% by weight of carbon, the lightness is 4.8, it is difficult to detect leakage light, and the coupling efficiency is 70 dB or more. In order to satisfy the cord contrast, it is necessary to add carbon in an amount of about 0.26% by weight or less and to have a lightness of 4.9 or more. Moreover, when carbon is reduced to about 0.03% by weight or less, the lightness becomes 6 or more and the cord contrast is improved.

  For cold resistance, the test piece is divided into two parts in the resin 18 containing 150 parts by weight of magnesium hydroxide. When the magnesium hydroxide is 125 parts by weight or less, the sample piece is not divided. Further, when magnesium hydroxide is blended in an amount of 65 parts by weight or less, cold resistance is further improved.

  As described above, a polyolefin resin containing magnesium hydroxide, red phosphorus, carbon, and titanium oxide is used for the gray jacket 14. With respect to 100 parts by weight of polyolefin resin, magnesium hydroxide is in a range of 65 parts by weight or more and 125 parts by weight or less, red phosphorus is in a range of 10 parts by weight or more and 25 parts by weight or less, carbon is 0.02% by weight or more, It mix | blends so that it may contain in the range of 0.26 weight part or less, and the titanium oxide in the range of 5 weight part or more and 10 weight part or less. As a result, the outer jacket 14 becomes a gray system, the aesthetics of the building or the like can be maintained, and the contrast of the cords is possible. Moreover, the characteristics required for the outer jacket 14 such as mechanical strength, flame retardancy, weather resistance, and cold resistance can be maintained.

  In the above description, a mixed resin of 30 parts by weight of EEA and 70 parts by weight of LLDPE is used as the polyolefin resin. In consideration of the heat resistance of EEA, the tensile strength, and the crystallinity of LLDPE, it is desirable to blend EEA: LLDPE, for example, in the range of 60 parts by weight to 40 parts by weight to 20 parts by weight.

(Other embodiments)
Although the embodiments of the present invention have been described as described above, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art. Accordingly, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

  The present invention can be applied to a subscriber optical fiber cable.

DESCRIPTION OF SYMBOLS 1 ... Optical indoor cable 2 ... Optical drop cable 4 ... Cable part 6 ... Support line part 8 ... Connection part 10 ... Optical fiber core wire 12 ... Strength member 14 ... Outer cover 16 ... Notch 18 ... Support line

Claims (3)

An optical fiber core,
A tensile body disposed in parallel with the optical fiber;
An outer sheath covering the optical fiber core and the tensile body,
The outer sheath is a polyolefin resin containing magnesium hydroxide, red phosphorus, carbon, and titanium oxide. Magnesium hydroxide ranges from 65 parts by weight to 125 parts by weight with respect to 100 parts by weight of the polyolefin resin. It contains phosphorus in the range of 10 to 25 parts by weight, carbon in the range of 0.02 to 0.249 % by weight, and titanium oxide in the range of 3 to 10 parts by weight. An optical fiber cable characterized by   The optical fiber cable according to claim 1, wherein the outer cover has a Munsell color system having a lightness of 4.9 or more. An optical fiber core,
A tensile body disposed in parallel with the optical fiber;
An outer sheath covering the optical fiber core and the tensile body,
The outer sheath is a polyolefin resin containing magnesium hydroxide, red phosphorus, carbon, and titanium oxide. Magnesium hydroxide ranges from 65 parts by weight to 125 parts by weight with respect to 100 parts by weight of the polyolefin resin. Containing phosphorus in the range of 10 to 25 parts by weight, carbon in the range of 0.02 to 0.26% by weight, titanium oxide in the range of 3 to 10 parts by weight,
An optical fiber cable, wherein the jacket has a Munsell color system having a lightness of 4.9 or more.

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