JP2007041379A - Flame-resistant coated optical fiber, flame-resistant optical fiber tape and flame-resistant optical fiber unit, and optical cord and optical cable using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame-resistant coated optical fiber having improved flame resistance, a flame-resistant optical fiber tape and a flame-resistant optical fiber nit, and an optical cord and an optical cable using the optical fiber. <P>SOLUTION: The coated optical fiber has coating layers 2, 3, 4 comprising an organic material applied on the outer circumference of a quartz glass fiber 1, wherein a dense coating layer 8 comprising particulate titanium oxide is applied on the outer circumference of the organic material coating layers 2, 3, 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a coated optical fiber, an optical fiber tape, and an optical fiber unit having a coating layer made of an organic material, and relates to a flame resistant coated optical fiber, a flame resistant optical fiber tape, and a flame resistant optical fiber unit with improved flame resistance. In addition, the present invention relates to an optical cord and an optical cable using the same.

  In recent years, with the expansion of optical fiber wiring to general households, the demand for various optical cords (those provided with an outer sheath around a coated optical fiber) is increasing. In addition, restrictions on the materials used are also increasing due to increased awareness of environmental resistance. Furthermore, the demand for smaller diameters is increasing due to space saving of wiring.

  A non-halogen thermoplastic resin is applied to the coating material of the optical cord. Further, by applying a coating material using a non-halogen flame retardant to the coating material of the optical cord, flame resistance is dealt with.

  On the other hand, the ultraviolet curable resin used for the coating material of the coated optical fiber is generally flammable. The flame retardancy of optical cords and optical cables using such coated optical fibers (a collection of a plurality of optical cords, optical fiber tapes, and optical fiber units) is usually provided on the outer periphery of a coating layer made of an ultraviolet curable resin. It is given by the flame retardancy of the exterior coating. Examples of the optical cord include those shown in FIG. 4, and examples of the optical cable include those shown in FIG. 5 and FIG.

  A conventional coated optical fiber 11 shown in FIG. 7A is provided with a primary coating layer 2 on the outer periphery of a quartz glass fiber (also referred to as a quartz glass strand) 1 and a secondary coating on the outer periphery of the primary coating layer 2. Layer 3 is provided. Further, the conventional coated optical fiber 12 shown in FIG. 7B is obtained by further providing a colored layer 4 on the outer periphery of the secondary coating layer 3 of the coated optical fiber 11 shown in FIG. The coated optical fiber 12 is used for general purposes as well as the field of information communication.

  The coated optical fiber includes a single-coated fiber in which only one coating layer made of an ultraviolet curable resin is provided on the outer periphery of the quartz glass fiber 1, but this is not shown. The illustrated coated optical fibers 11 and 12 are formed of a hard ultraviolet curable resin having a primary coating layer 2 formed of a soft ultraviolet curable resin having a buffering role and having a role of protecting against external damage on the outer periphery of the primary coating layer 2. And the secondary coating layer 3 is formed. Further, on the outer periphery of the secondary coating layer 3, a colored layer 4 is formed of an ultraviolet curable resin as a coating layer for identification by color.

  The conventional optical fiber tape 13 shown in FIG. 8 is provided with a primary coating layer 2 on the outer periphery of the quartz glass fiber 1, a secondary coating layer 3 is provided on the outer periphery of the primary coating layer 2, and the secondary coating layer 3 A coated optical fiber further provided with a colored layer 4 on the outer periphery, that is, a plurality of coated optical fibers 12 in FIG. 7B are arranged in order, and a tape layer 5 that covers the plurality of coated optical fibers 12 is provided. It is a thing. The tape layer 5 is also made of an ultraviolet curable resin.

  In the conventional optical fiber unit 14 shown in FIG. 9, a primary coating layer 2 is provided on the outer periphery of the silica glass fiber 1, a secondary coating layer 3 is provided on the outer periphery of the primary coating layer 2, and the secondary coating layer 3 A plurality of coated optical fibers provided with a colored layer 4 on the outer periphery, that is, a plurality of coated optical fibers 12 shown in FIG. 7B are arranged around the tension member 6, and the plurality of coated optical fibers 12 and the tension member 6 are arranged. A unit layer 7 is provided to cover all together. The unit layer 7 is also made of an ultraviolet curable resin.

  An ultraviolet curable resin having a Young's modulus of 0.5 to 10 MPa is used for the primary coating layer 2, and an ultraviolet curable resin having a Young's modulus of 100 to 2000 MPa is used for the secondary coating layer 3. Further, an ultraviolet curable resin having a Young's modulus of 100 to 2000 MPa is used for the optical fiber tape 13, the tape layer 5 of the optical fiber unit 14, and the unit layer 7.

  Examples of the ultraviolet curable resin include urethane (meth) acrylate resins, polyester (meth) acrylate resins, silicone (meth) acrylate resins, epoxy (meth) acrylate resins, and fluorine (meth) acrylate resins. Of these, there is no particular limitation, but urethane acrylate-based ultraviolet curable resins are preferable in terms of versatility and cost. Examples of the urethane acrylate ultraviolet curable resin include polyester urethane (meth) acrylate, polyether urethane (meth) acrylate, and polycarbonate (meth) urethane acrylate.

JP-A-6-118285 JP-A-5-157950 JP 2003-344726 A Japanese Utility Model Publication No. 5-96811 "Industrial Materials", November 2004, page 36 http: // uniluck. jp / 2.10. html April 1, 2005 http: // www. barjp. com / kinuya / hitokuti / 02ti April 1, 2005

  As described above, the ultraviolet curable resin used for the material of the coating layers 2, 3 and 4 of the coated optical fibers 11 and 12 is flammable. If a flame retardant is added in order to impart flame retardancy to the material of the coating layers 2, 3 and 4, the mechanical properties are lowered. Specifically, the deterioration of mechanical properties means that the material is easily cracked, does not stretch, is difficult to solidify, becomes brittle, and the like.

  On the other hand, when an outer sheath (not shown) is provided on the outer periphery of the coating layers 2, 3, and 4 of the coated optical fibers 11 and 12, the outer sheath is often provided with a halogen-free flame retardancy. It is necessary to add a flame retardant. However, when many flame retardants are added, problems such as poor extrudability, poor appearance, whitening, and easy damage are likely to occur.

  Furthermore, if the exterior coating is thinned to cope with the reduction in diameter, when a material highly filled with a flame retardant is used, the exterior coating is likely to break during extrusion. Further, the presence of flame retardant aggregates causes breakage of the outer sheath during terminal processing and wiring work.

  In summary, when a flame retardant is added to the material of the coating layers 2, 3, 4 of the coated optical fibers 11, 12, defects occur in the properties of the coating layers 2, 3, 4 themselves, If the exterior covering covering 4 is made flame retardant, there is a problem that a problem occurs in extrusion processability and appearance. Furthermore, it is very difficult to reduce the thickness of the outer covering.

  Further, since the tape layer 5 and the unit layer 7 are made of a flammable ultraviolet curable resin, it is necessary to improve the flame resistance of the optical fiber tape 13 and the optical fiber unit 14 as well.

  Accordingly, an object of the present invention is to provide a flame resistant coated optical fiber, a flame resistant optical fiber tape, a flame resistant optical fiber unit, an optical cord and an optical cable using the same, which solve the above problems and have improved flame resistance. It is in.

  In order to achieve the above object, according to a first invention, in a coated optical fiber in which a coating layer made of an organic material is provided on the outer periphery of a silica glass fiber, a dense coating layer made of fine particle titanium oxide is provided on the outer periphery of the coating layer. Is.

  A second invention is a tape layer made of an organic material that covers a plurality of coated optical fibers arranged in order, with a plurality of coated optical fibers provided with a coating layer made of an organic material on the outer periphery of a quartz glass fiber. In the optical fiber tape provided with the above, a dense coating layer made of fine particle titanium oxide is provided on the outer periphery of the tape layer.

  According to a third aspect of the present invention, a plurality of coated optical fibers provided with a coating layer made of an organic material on the outer periphery of a quartz glass fiber are arranged around a tension member, and the plurality of coated optical fibers and the tension member are collectively collected. In the optical fiber unit provided with a unit layer made of an organic material to be covered, a dense coating layer made of fine particle titanium oxide is provided on the outer periphery of the unit layer.

  In the first invention, the organic material may be an ultraviolet curable resin.

  In the first invention, the organic material may be a thermosetting resin.

  In the second invention, the organic material may be an ultraviolet curable resin.

  In the second invention, the organic material may be a thermosetting resin.

  In the third invention, the organic material may be an ultraviolet curable resin.

  In the third invention, the organic material may be a thermosetting resin.

  By providing at least an outer sheath around the flame-resistant coated optical fiber produced according to the first invention, an optical cord having excellent flame resistance can be produced.

  An optical cable excellent in flame resistance can be produced by providing at least an outer sheath around the assembly of a plurality of flame resistant optical fiber tapes produced according to the second invention.

  An optical cable having excellent flame resistance can be produced by providing at least an outer sheath around the assembly of a plurality of flame resistant optical fiber units produced according to the third invention.

  The present invention exhibits the following excellent effects.

  (1) The flame resistance of the coated optical fiber can be increased.

  (2) The flame resistance of the optical fiber tape can be increased.

  (3) The flame resistance of the optical fiber unit can be increased.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  As a result of various studies in order to solve the above problems, the applicant of the present invention can easily form a dense film on the surface of a conventional coated optical fiber, the surface of a conventional optical fiber tape, or an optical fiber unit. It has been found that it is effective to coat a ceramic film with fine particulate titanium oxide.

  According to Non-Patent Document 1, the photocatalytic ceramic coating film is a dense film that does not allow oxygen to pass through. By providing the photocatalytic ceramic coating film on the material to be coated, it is difficult to ignite, burn, and generate harmful gases due to combustion. The effect of not doing is obtained.

  According to Non-Patent Documents 2 and 3, titanium oxide is a photocatalyst. Therefore, if a dense film that does not pass oxygen is formed by ceramic coating fine particle titanium oxide on the outer periphery of the coating layer, the outer periphery of the tape layer, and the outer periphery of the unit layer, the coated optical fiber, optical fiber tape, and optical fiber unit Flame resistance can be increased.

The structure of fine particle titanium oxide is not particularly limited. For example, TiO ₂ , TiO _2-X (Marukatsu Sangyo Co., Ltd.), TiO _2-X N _X (Ishihara Sangyo Co., Ltd.) and ceramics are partially covered with ceramic. Titanium oxide hybrid (Taihei Chemical Industry Co., Ltd., Showa Denko Co., Ltd.).

  Although it does not specifically limit as thickness (film thickness) of a coating layer, It is preferable to set it as 5 micrometers or less. To make it thicker than 5 μm, the number of repeated coatings increases. On the other hand, when the thickness is greater than 5 μm, problems such as cracking or peeling of the ceramic layer are likely to occur due to bending or the like. More preferably, the thickness of the coating layer is 0.1 μm to 2 μm. When it becomes thinner than 0.1 μm, it becomes difficult to obtain sufficient flame resistance.

  The flame-resistant coated optical fiber according to the present invention is a coated optical fiber in which a coating layer made of an organic material is provided on the outer periphery of a quartz glass fiber, and a dense coating layer made of fine particle titanium oxide is provided on the outer periphery of the organic material coating layer. It is provided.

  In the form shown in FIG. 1, an ultraviolet curable resin is used as the organic material. 1 is provided with a primary coating layer 2 on the outer periphery of the silica glass fiber 1, a secondary coating layer 3 on the outer periphery of the primary coating layer 2, and the secondary coating layer 3. In the coated optical fiber in which the colored layer 4 is further provided on the outer periphery, that is, in the coated optical fiber 12 in FIG. 7B, the dense coating layer 8 made of fine particle titanium oxide is provided on the outer periphery of the colored layer 4.

  2 is provided with a primary coating layer 2 on the outer periphery of the silica glass fiber 1 and a secondary coating layer 3 on the outer periphery of the primary coating layer 2. A coated optical fiber in which a colored layer 4 is further provided on the outer periphery of the coating layer 3, that is, a plurality of coated optical fibers 12 in FIG. 7B are arranged in order, and the tape covering the plurality of coated optical fibers 12 collectively. In the optical fiber tape provided with the layer 5, that is, the optical fiber tape 13 of FIG. 8, a dense coating layer 17 made of fine particle titanium oxide is provided on the outer periphery of the tape layer 5.

  3 is provided with a primary coating layer 2 on the outer periphery of the silica glass fiber 1 and a secondary coating layer 3 on the outer periphery of the primary coating layer 2. A plurality of coated optical fibers in which the colored layer 4 is further provided on the outer periphery of the coating layer 3, that is, the coated optical fibers 12 shown in FIG. 7B are arranged around the tension member 6, and the plurality of coated optical fibers 12 In the optical fiber unit provided with the unit layer 7 that collectively covers the tension member 6, that is, the optical fiber unit 14 of FIG. 9, a dense coating layer 19 made of fine particle titanium oxide is provided on the outer periphery of the unit layer 7.

  Since the outermost layers of the flame resistant coated optical fiber 15, the flame resistant optical fiber tape 16, and the flame resistant optical fiber unit 18 are the dense coating layers 8, 17, and 19 made of fine particle titanium oxide, the dense coating layer 8 , 17 and 19, the flammable ultraviolet curable resin in the inner layer is shielded from oxygen and becomes difficult to burn, and the flame resistance is improved.

  The present invention is not limited to a coating layer, a tape layer, a coated optical fiber having a unit layer, an optical fiber tape, or an optical fiber unit, but a coated optical fiber having a coating layer, a tape layer, or a unit layer made of a thermosetting resin. It can also be applied to optical fiber tapes and optical fiber units.

  The present invention can also be applied to the outermost layer such as an optical cord or an optical cable.

  Hereinafter, in order to confirm the effect of the present invention, a flame resistant coated optical fiber 15 called Example I, a flame resistant optical fiber tape 16 called Example II, and a flame resistant optical fiber unit 18 called Example III were prepared. For further comparison, a conventional coated optical fiber 12 called Comparative Example I and a conventional optical fiber tape 13 called Comparative Example II were prepared, and these samples were subjected to a combustion test.

In Example I, first, a urethane acrylate UV curable resin having a Young's modulus of 1.0 ± 0.2 MPa as a primary coating layer 2 at a speed of 1200 m / min on the outer periphery of a quartz glass fiber 1 having a diameter of 125 ± 1 μm is 35 μm thick. The primary coating layer 2 is cured by coating and passing through an ultraviolet irradiation device (Fusion 6 kW × 1 lamp: output 80%). After that, the secondary coating layer 3 is coated with a urethane acrylate ultraviolet curable resin having a Young's modulus of 800 ± 100 MPa to a thickness of 25 μm, and passed through an ultraviolet irradiation device (Fusion 6 kW × 4 lamps: output 90%). 3 was cured. Further, a colored UV ink (751 made by DSM) is coated as a colored layer 4 with a thickness of 5 μm, and the colored layer 4 is cured by passing it through an ultraviolet irradiation device (Fusion 6 kW × 2 lamp: output 90%), and coated optical fiber 12 was obtained. The coated optical fiber 12 is coated with a photocatalytic titanium oxide having a particle diameter of 7 nm (STS-01 Ishihara Sangyo Co., Ltd .; TiO ₂ concentration 30 wt%, solvent is alcohol) as a dense coating layer 8 to a thickness of about 0.2 μm. It was passed through an oven and dried to obtain a flame resistant coated optical fiber 15.

In Example II, four coated optical fibers 12 having an outer diameter of 255 μm produced in the same manner as in Example I were arranged in parallel. The outer periphery of these coated optical fibers 12 is coated as a tape layer 5 with urethane acrylate-based ultraviolet curable resin having a Young's modulus of 700 ± 100 MPa, and passed through an ultraviolet irradiation device (Fusion 6 kW × 2 lamp: output 90%). Layer 5 was cured. Thereby, an optical fiber tape 13 having a thickness of 0.3 mm was obtained. Thereafter, a photocatalytic titanium oxide (NTB-13 Showa Denko KK; TiO ₂ concentration 3 wt%, solvent is water / alcohol mixed solvent) having a particle diameter of 10 to 35 nm as a dense coating layer 17 on the outer periphery of the tape layer 5 is about 0 in thickness. The film was coated with .25 μm and dried by passing through a near infrared furnace to obtain a flame resistant coated optical fiber tape 16.

In Example III, six coated optical fibers 12 having an outer diameter of 255 μm produced in the same manner as in Example I were arranged on the outer periphery of the FRP tension member 6 having a diameter of 1 mm. The outer periphery of the coated optical fiber 12 and the tension member 6 is coated as a unit layer 7 with urethane acrylate-based ultraviolet curable resin having a Young's modulus of 700 ± 100 MPa, and applied to an ultraviolet irradiation device (Fusion 6 kW × 2 lamp: output 90%). The unit layer 7 was cured by passing it through. Thereby, an optical fiber unit 14 having an outer diameter of 2 mm was obtained. Thereafter, a photocatalytic titanium oxide having a particle diameter of 10 to 35 nm (NTB-13 Showa Denko KK; TiO ₂ concentration 3 wt%, solvent is water / alcohol mixed solvent) as a dense coating layer 19 on the outer periphery of the unit layer 7 is about 0 in thickness. .25 μm was coated and dried by passing through a near infrared furnace to obtain a flame resistant coated optical fiber unit 18.

  Comparative Example I is a coated optical fiber 12 produced in the same manner as Example I.

  Comparative Example II is an optical fiber tape 13 produced in the same manner as Example II.

  Samples obtained as Example I, Example II, Example III, Comparative Example I, and Comparative Example II were subjected to the following combustion test.

  The horizontal combustion test is based on the horizontal flame retardant test described in JIS C 3005 “Plastic insulated wire test method” and evaluates the flame resistance of the coated optical fibers 12 and 15 and the optical fiber tapes 13 and 16 and the optical fiber unit 18. It is a test. After removing the flame, the flame extinguished within 15 seconds was accepted and the fire spread was rejected.

  The vertical combustion test is a test for evaluating the flame resistance of the coated optical fibers 12 and 15 and the optical fiber tapes 13 and 16 and the optical fiber unit 18 in conformity with UL Subject 758 and UL1581 (UL VW-1). Apply a tyryl burner flame at an angle of 20 ° to the sample, ignite 15 seconds and pause for 15 seconds 5 times, the residual flame does not exceed 60 seconds, the indicator does not burn more than 25%, and falls The thing which the surgical cotton of the bottom part did not burn by a thing was set as the pass, and the thing which does not satisfy any one was made into the rejection.

  Table 1 shows the evaluation results of the horizontal combustion test and the vertical combustion test.

  As shown in Table 1, Example I, Example II, and Example III passed both the horizontal combustion test and the vertical combustion test, while Comparative Example I and Comparative Example II showed both the horizontal combustion test and the vertical combustion test. Is also rejected. From this, the outermost layers, such as the flame-resistant coated optical fiber 15, the flame-resistant optical fiber tape 16, and the flame-resistant optical fiber unit 18 of the present invention, are dense coating layers 8, 17, and 19 made of fine particle titanium oxide, and It has been demonstrated that the flame resistance can be increased by doing so.

1 is a cross-sectional view of a flame resistant coated optical fiber showing an embodiment of the present invention. It is sectional drawing of the flame-resistant optical fiber tape which shows one Embodiment of this invention. It is sectional drawing of the flame-resistant optical fiber unit which shows one Embodiment of this invention. It is sectional drawing of the optical cord which shows one Embodiment of this invention. It is sectional drawing of the optical cable which shows one Embodiment of this invention. It is sectional drawing of the optical cable which shows one Embodiment of this invention. (A), (b) is sectional drawing of the conventional coated optical fiber, respectively. It is sectional drawing of the conventional optical fiber tape. It is sectional drawing of the conventional optical fiber unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Quartz glass fiber 2 Primary coating layer 3 Secondary coating layer 4 Colored layer 5 Tape layer 6 Tension member 7 Unit layer 8, 17, 19 Dense coating layer 15 Flame resistant coated optical fiber 16 Flame resistant optical fiber tape 18 Flame resistant optical fiber unit

Claims (12)

  A coated optical fiber in which a coating layer made of an organic material is provided on the outer periphery of a quartz glass fiber, and a dense coating layer made of fine particle titanium oxide is provided on the outer periphery of the coating layer.   An optical fiber tape in which a plurality of coated optical fibers provided with a coating layer made of an organic material are arranged in order on the outer periphery of a quartz glass fiber, and a tape layer made of an organic material covering the plurality of coated optical fibers at once is provided. A flame resistant optical fiber tape, wherein a dense coating layer made of fine particle titanium oxide is provided on the outer periphery of the tape layer.   A unit made of an organic material in which a plurality of coated optical fibers each provided with a coating layer made of an organic material on the outer periphery of a quartz glass fiber are arranged around the tension member and collectively covers the plurality of coated optical fibers and the tension member. An optical fiber unit provided with a layer, wherein a dense coating layer made of fine particle titanium oxide is provided on the outer periphery of the unit layer.   The flame resistant coated optical fiber according to claim 1, wherein the organic material is an ultraviolet curable resin.   The flame resistant coated optical fiber according to claim 1, wherein the organic material is a thermosetting resin.   3. The flame resistant optical fiber tape according to claim 2, wherein the organic material is an ultraviolet curable resin.   The flame resistant optical fiber tape according to claim 2, wherein the organic material is a thermosetting resin.   4. The flame resistant optical fiber unit according to claim 3, wherein the organic material is an ultraviolet curable resin.   4. The flame resistant optical fiber unit according to claim 3, wherein the organic material is a thermosetting resin.   An optical cord produced by providing at least an outer sheath around the flame resistant coated optical fiber according to claim 1.   An optical cable produced by providing at least an outer sheath around a collection of a plurality of the flame-resistant optical fiber tapes according to any one of claims 2, 6, and 7. An optical cable produced by providing at least an outer sheath around an assembly of a plurality of the flame-resistant optical fiber units according to any one of claims 3, 8, and 9.

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