JP2019168553A - Optical fiber ribbon - Google Patents

Abstract

To provide an optical fiber ribbon in which a coupling portion is not unexpectedly peeled, and connecting and branching work of an optical fiber can be easily executed.SOLUTION: An optical fiber ribbon 10 comprises a plurality of optical fibers 1 having a colored layer and a plurality of coupling portions 2 for coupling the two adjacent optical fibers 1 to each other. When an adhesion between the colored layer and the coupling portion 2 is defined as A [N/mm] and a tearing force at the time of tearing the coupling portion 2 is defined as S [gf], 0.38≤A≤4.30 and 1.0≤S≤17.0 are satisfied.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an optical fiber ribbon.

  Conventionally, an optical fiber ribbon as shown in Patent Document 1 below is known. This optical fiber ribbon has a plurality of connecting portions that intermittently connect adjacent optical fibers. An optical fiber ribbon is generally housed in a sheath and used as an optical fiber cable.

Japanese Patent No. 4143651

This type of optical fiber ribbon is required to prevent the connecting portion from being unexpectedly peeled when an optical fiber cable is manufactured. For this purpose, it is necessary to bring the connecting portion into close contact with the optical fiber with some strength.
On the other hand, when connecting or branching the optical fiber after laying the optical fiber cable, the optical fiber may be separated into a single core by pulling the optical fibers by hand so as to be separated from each other. Desired. At this time, if the adhesion of the connecting portion to the optical fiber is too strong, for example, the coating layer of the optical fiber may be peeled off from the surface of the glass fiber, and the optical fiber may be damaged. Further, it is preferable that the connecting portion can be easily removed from the optical fiber after the optical fiber is separated into single cores.

  The present invention has been made in consideration of such circumstances, and it is an object of the present invention to provide an optical fiber ribbon capable of easily connecting and branching an optical fiber without causing a connection portion to be unexpectedly separated. Objective.

In order to solve the above problems, an optical fiber ribbon according to an aspect of the present invention includes a plurality of optical fibers having a colored layer, and a plurality of connecting portions that connect the two adjacent optical fibers. When the adhesive force between the colored layer and the connecting portion is A [N / mm ² ] and the tearing force when tearing the connecting portion is S [gf], 0.38 ≦ A ≦ 4. 30 and 1.0 ≦ S ≦ 17.0 are satisfied.

  According to the above aspect of the present invention, it is possible to provide an optical fiber ribbon in which the connecting portion is not abruptly peeled and the optical fiber can be easily connected and branched.

It is the schematic explaining the structure of the optical fiber tape cable core which concerns on this embodiment. FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1, where (a) shows a case where two optical fibers are not in contact with each other and a connecting portion is inserted between them; When the fibers are not in contact with each other and the connecting portion covers the entire circumference of the two optical fibers, (c) shows that the two optical fibers are in contact with each other and the connecting portion has two optical fibers. The case where the entire circumference is covered is shown. (A) is the schematic explaining the measuring method of the adhesive force of a colored layer and a connection part, (b) is a BB cross-sectional arrow view of (a). It is the schematic explaining the measuring method of tearing force S at the time of tearing a connection part. (A) is the schematic explaining the ironing test method of a 12-fiber optical fiber ribbon, (b) is the schematic explaining the ironing test method of a 4-core or 8-fiber optical fiber ribbon.

The configuration of the optical fiber ribbon according to the present embodiment will be described below with reference to FIGS. 1 and 2.
In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent. Further, the present invention is not limited to the following embodiment.

  As shown in FIG. 1, the optical fiber ribbon 10 has a configuration in which a plurality of optical fibers or an optical fiber (hereinafter simply referred to as an optical fiber 1) are connected by a plurality of connecting portions 2. Yes. As shown in FIG. 2A, the optical fiber 1 includes a glass fiber 1a, a coating layer 1b, and a colored layer 1c. The glass fiber 1a is formed of, for example, quartz glass and transmits light. The covering layer 1b is formed of a UV curable resin or the like and covers the glass fiber 1a. The coating layer 1b may be a single layer or may be composed of a plurality of layers including a primary layer and a secondary layer. The colored layer 1c is formed of a colored UV curable resin or the like and covers the coating layer 1b. In order to distinguish between the plurality of optical fibers 1, each optical fiber 1 has a colored layer 1c of a different color. The outer diameter of the optical fiber 1 (the outer diameter of the colored layer 1c) is, for example, about 252 μm.

(Direction definition)
In the present embodiment, the direction in which the optical fiber 1 extends is simply referred to as the longitudinal direction. A direction perpendicular to the longitudinal direction and in which a plurality of optical fibers 1 are arranged is referred to as a width direction. A cross section perpendicular to the longitudinal direction is referred to as a transverse cross section.

  The connecting part 2 is formed of, for example, a UV curable resin or a thermosetting resin. The connecting portion 2 enters between the two adjacent optical fibers 1 and connects the optical fibers 1 to each other. Moreover, in the part in which the connection part 2 is not formed, the optical fibers 1 are not connected but can be separated.

  More specifically, a plurality of optical fibers 1 are arranged, and adjacent optical fibers 1 are connected by a connecting portion 2. The connecting portions 2 are arranged at regular intervals in the longitudinal direction. With respect to the position of the connecting portion 2 that connects the adjacent optical fibers 1, the connecting portion 2 that connects one of the adjacent optical fibers 1 and the other optical fiber 1 adjacent thereto is shifted in the longitudinal direction. Placed in position. Thus, the connection part 2 is arrange | positioned in zigzag form (zigzag shape) with respect to the bidirectional | two-way of the width direction orthogonal to the longitudinal direction and longitudinal direction of the optical fiber tape core wire 10. FIG.

  For example, the optical fibers 1 connected to each other by the connecting portion 2 are pulled apart from each other in the width direction of the optical fiber ribbon 10 with fingers, so that the connecting portions 2 are separated from the optical fiber 1 by the force of the fingers. Thus, the connected state can be released. The configuration and material of the optical fiber ribbon 10 are not limited to the above, and can be changed as appropriate.

  Although FIG. 1 and FIG. 2A show a case where the connecting portion 2 does not cover the entire circumference of the optical fiber 1, the aspect of the connecting portion 2 may be changed as appropriate. For example, as shown in FIG. 2B, the connecting portion 2 may cover the entire circumference of these optical fibers 1 in a state where the adjacent optical fibers 1 are separated in the width direction. Or as shown in FIG.2 (c), the connection part 2 may cover the perimeter of these optical fibers 1 in the state which adjacent optical fibers 1 contacted in the width direction.

  By the way, such an optical fiber ribbon 10 is generally housed in a sheath (not shown) and used as an optical fiber cable. In recent years, it has been demanded that the optical fiber 1 be accommodated in the sheath at a high density, and the strain and tension acting on the connecting portion 2 during the production of the optical fiber cable tend to increase. In order to prevent the connection part 2 from being peeled off unexpectedly during the production of the optical fiber cable, the connection part 2 is required to be in close contact with the colored layer 1c with a certain degree of strength.

  On the other hand, when performing an intermediate post-branching operation after laying the optical fiber cable, it is required that the optical fibers 1 be separated into a single core by pulling adjacent optical fibers 1 together. At this time, if the adhesion between the connecting portion 2 and the colored layer 1c is too large, for example, the coating layer 1b may be peeled off from the surface of the glass fiber 1a, and the optical fiber 1 may be damaged.

  Further, when the optical fiber 1 is separated into single cores and the resin piece of the connecting portion 2 adhering to the surface of the optical fiber 1 cannot be easily removed, there is a problem in attaching an optical connector or the like to the end of the optical fiber 1. May occur. For example, when the optical fiber 1 is inserted into the optical connector, the remaining resin piece of the connecting portion 2 is sandwiched between the optical fiber 1 and the inner wall of the optical connector, and microbending occurs in the optical fiber 1. It is done. Or it is possible that the said resin piece is pinched | interposed between the optical fiber incorporated in the optical connector, and the inserted optical fiber 1, and a connection precision falls. For this reason, it is preferable that the connecting portion 2 can be easily removed from the optical fiber 1 after the optical fiber 1 is separated into a single core.

  Based on the above, with respect to the requirements for the connection part 2 not to be unexpectedly peeled off during the production of the optical fiber cable and to be able to easily connect and branch the optical fiber, a specific example is used. explain.

  In this example, a plurality of optical fiber ribbons 10 shown in Table 1 and Table 2 below were created. In samples 1-1 to 1-24 shown in Table 1, the optical fiber 1 having an outer diameter of the glass fiber 1a of 125 μm, an outer diameter of the coating layer 1b of 239 to 242 μm, and an outer diameter of the colored layer 1c of 252 μm is used. . In Samples 2-1 to 2-23 shown in Table 2, the optical fiber 1 is used in which the outer diameter of the glass fiber 1a is 125 μm, the outer diameter of the coating layer 1b is 191 to 193 μm, and the outer diameter of the colored layer 1c is 205 μm. .

  Each sample shown in Table 1 and Table 2 is a 12-core optical fiber ribbon 10 having 12 optical fibers 1. “Adhesion force A” in Tables 1 and 2 indicates the results of the adhesion force measurement described later. The “connecting part tearing force S” indicates the result of the connecting part tearing force measurement described later. “Optical fiber observation results after adhesion strength measurement”, “single-core separation property”, “connection part removal property”, and “number of connection part peeling after ironing test” each take into account the manufacture or use of the optical fiber ribbon 10 Evaluation items (details will be described later) are shown.

In this example, an ultraviolet curable resin was used as a material for the colored layer 1c and the connecting portion 2.
When producing the optical fiber 1 in each sample, when the material to be the colored layer 1c is applied to the outer periphery of the coating layer 1b and cured by ultraviolet rays, the surface hardening degree of the material is changed by changing the oxygen concentration at the time of curing. It is different.
As a material for forming the colored layer 1c, a material having a Young's modulus after curing of 800 MPa, a tensile strength of 40 MPa, and an elongation at break of 8% was used. In addition, even if the oxygen concentration at the time of hardening of the colored layer 1c is changed, the Young's modulus does not change greatly. This is because only the degree of curing of the surface of the colored layer 1c of the optical fiber 1 in each sample is different.

And the some sample from which the contact | adhesion power of the colored layer 1c and the connection part 2 differs mutually is produced by forming the connection part 2 which connects those optical fibers 1 mutually.
A material having a Young's modulus after curing of 850 MPa, a tensile strength of 46 MPa, and a tensile elongation of 53% was used as the connecting portion 2. The Young's modulus, tensile strength, and tensile elongation were measured based on JIS K 7113.

The 12-fiber optical fiber ribbon 10 produced as described above was subjected to adhesion force measurement, connection portion tear force measurement, single-core separation evaluation, connection portion removability evaluation, and ironing test.
Hereinafter, each measurement method or evaluation method will be described.

(Adhesion measurement)
In the adhesion force measurement, an adhesion force A [N / mm ² ] per unit area between the colored layer 1c and the connecting portion 2 is measured. A method for measuring the adhesion A will be described with reference to FIGS. 2 (a) to 2 (c) and FIGS. 3 (a) and 3 (b).
First, out of the 12-core optical fiber ribbon 10, two adjacent optical fibers 1 connected by the connecting portion 2 are taken out. At this time, the length of one optical fiber 1 is, for example, about 60 mm. As shown in FIG. 3, the first end E1 of one optical fiber 1 is not connected to the other optical fiber 1, and the second end E2 of the one optical fiber 1 is not connected to the other light. The fiber 1 is connected by a connecting part 2. For the first end E1 and the second end E2, the outer diameter of the colored layer 1c is measured from two directions orthogonal to the central axis of the optical fiber 1, and the average of these is the colored layer outer diameter D [mm]. .

Next, as shown in FIG. 3, the connection part 2 provided in the 2nd end part E2 is fixed to the top 3, and the sample for a measurement is produced. The method for fixing the connecting portion 2 to the frame 3 is not particularly limited, but in the present embodiment, the connecting portion 2 is fixed with an adhesive 31. In this case, a measurement sample is prepared so that the adhesive 31 and the optical fiber 1 do not come into contact with each other.
Next, a cut is made in the covering layer 1b and the colored layer 1c of the optical fiber 1 having the second end E2. The position in the longitudinal direction at which the cut is made is the end of the top 3 on the second end E2 side.

  Next, in a state where the connecting portion 2 is fixed to the frame 3, the first end E <b> 1 of the optical fiber 1 whose color layer outer diameter D is measured is pulled away from the frame 3. In this test, a tensile tester or the like that can pull out the optical fiber 1 at a predetermined speed (for example, 3 mm / min) while measuring force is used. And peeling arises from the interface of the colored layer 1c and the connection part 2, etc., and the maximum value T [N] of the drawing force when the optical fiber 1 is drawn is measured. In addition, you may cut | disconnect suitably the optical fiber 1 which is not pulled out of the two optical fibers 1 so that a measurement may not be disturbed.

For the adhesion force A [N / mm ² ] per unit area, the maximum value T [N] of the pulling force measured as described above is the area of the interface between the colored layer 1c and the connecting portion 2 (hereinafter referred to as interface area I). [Mm ² ]). That is, the adhesion force A can be calculated by the following formula (1).
A = T / I (1)

As shown in FIG. 2A, when the connecting portion 2 does not cover the entire circumference of the optical fiber 1 and the two optical fibers 1 are not in contact with each other, the interface area I is expressed by the following formula ( 2). In Equation (2), θ [°] is an angle centered on the central axis of the optical fiber 1 of the portion of the optical fiber 1 that is not covered by the connecting portion 2 in a cross-sectional view. L [mm] in Expression (2) is the length in the longitudinal direction of the portion of the connecting portion 2 to which tension is applied when the first end E1 is pulled as described above. D [mm] in Equation (2) is the colored layer outer diameter D described above.
I = D × π × ((360−θ) / 360) × L (2)

As shown in FIG. 2B, when the two optical fibers 1 are not in contact and the resin of the connecting portion 2 covers the entire circumference of the two optical fibers 1, the interface area I is It is calculated by the following formula (3).
I = D × π × L (3)

  As shown in FIG. 2C, when the two optical fibers 1 are in contact with each other and the connecting portion 2 covers the entire circumference of the two optical fibers 1, the interface area I is as described above. It can obtain | require by Numerical formula (2).

In this example, the optical fiber 1 after measuring the adhesive force A was observed, and from which interface the optical fiber 1 was peeled was confirmed. Results ”. More specifically, the case where the peeling occurs at the interface between the colored layer 1c and the connecting portion 2 is OK. ^{(1) Although} some of the glass fibers 1a are exposed, the interface between the colored layer 1c and the connecting portion 2 is mostly used. The case where the glass fiber 1a was peeled off was indicated as OK ⁽²⁾ , and the case where the exposure of the glass fiber 1a was observed in most cases was indicated as NG. In Tables 1 and 2, OK is displayed as a pass or pass judgment, and NG is displayed as a pass or fail determination.

(Measurement of tearing force at joints)
In the connection portion tearing force measurement, a force required to tear the connection portion 2 by pulling the optical fibers 1 apart from each other (hereinafter referred to as a connection portion tearing force S) is measured. A method for measuring the connecting portion tearing force S will be described with reference to FIG.
First, out of the 12-core optical fiber ribbon 10, two adjacent optical fibers 1 connected by the connecting portion 2 are taken out. At this time, for example, the length from the ends P1 and P3 of the two optical fibers 1 to the end of the connecting portion 2 is about 100 mm, and the end P2 of the two optical fibers 1 from the end of the connecting portion 2 The length up to P4 is about 150 mm.

  Next, as shown in FIG. 4, the end portion P <b> 3 of one optical fiber 1 is fixed to the fixture 4. Then, the end portion P1 of the other optical fiber 1 is pulled at a pulling rate of 100 mm / min, and the maximum value [gf] of the tearing force until the connecting portion 2 is torn and separated into two optical fibers 1 is measured. This maximum value is the connecting portion tearing force S.

(Single core separation evaluation)
In the single-fiber separation evaluation, the optical fibers 1 are pulled apart from each other to tear the connecting portion 2 and the optical fiber 1 after being separated into single fibers is observed to evaluate whether the coating layer 1b or the like is damaged. . This is an evaluation for confirming that the optical fiber 1 is not damaged when the optical fiber tape core wire 10 is separated into single cores with fingers during, for example, an intermediate post-branching operation.
The column of “single-core separation” in Tables 1 and 2 shows the results of confirming whether the colored layer 1c and the connecting part 2 were peeled after tearing the connecting part 2. More specifically, when the coating layer 1b has no abnormality and the colored layer 1c and the connecting portion 2 are separated and separated into two optical fibers 1, the result is good and indicated as OK. In addition, when the colored layer 1c or the covering layer 1b is broken or the glass fiber 1a is exposed, the result is indicated as NG.

(Evaluation of removability of connecting part)
In connection part removability evaluation, it is evaluated whether the resin piece of the connection part 2 adhering to the optical fiber 1 after single core separation is easily removable. More specifically, the optical fiber 1 to which the resin piece of the connecting part 2 after the evaluation of the single-fiber separation is attached is rubbed with abrasive paper, and the resin piece of the connecting part 2 is removed from the surface of the colored layer 1c of the optical fiber 1 The number of times it took to be evaluated was evaluated. The abrasive paper used was a micropolynet sheet WA-600 (particle size 20 μm) manufactured by Koyo Co., Ltd. In Tables 1 and 2, when the number of rubbing was 7 or less and the resin piece of the connecting portion 2 could be removed, the result was shown as OK. In addition, when the number of times of rubbing until the resin piece of the connecting portion 2 is removed is required to be 8 times or more, the result is indicated as NG. In the case of NG, NG ^* was particularly indicated when the exposure of the glass fiber 1a was observed after rubbing with abrasive paper.

(Squeeze test)
The ironing test of the present example simulates ironing applied to the optical fiber ribbon 10 in the manufacturing apparatus when the optical fiber cable mounted with the optical fiber ribbon 10 is manufactured. In the ironing test, it is confirmed whether or not the connecting portion 2 is unexpectedly peeled off when the optical fiber cable is manufactured.
In the ironing test, a ironing device 40 as shown in FIGS. 5A and 5B is used. The ironing device 40 includes a plurality of (four in this embodiment) horizontal mandrels 41 extending in the horizontal direction, a vertical mandrel 42 extending in the vertical direction, and a pulley 43. The horizontal mandrel 41 and the vertical mandrel 42 are formed in a round bar shape and are rotatable around their respective central axes. In this example, a metal round bar with a diameter of 6 mm was used as the horizontal mandrel 41, and a round metal bar with a diameter of 7 mm was used as the vertical mandrel 42.

  The four horizontal mandrels 41 are arranged at equal intervals in the vertical direction with a center distance of 8 mm. The vertical mandrel 42 is disposed in the vicinity of the four horizontal mandrels 41. The pulley 43 is disposed above the plurality of horizontal mandrels 41. The central axis of the pulley 43 is arranged in a posture substantially parallel to the central axis of the horizontal mandrel 41 and spaced from the nearest horizontal mandrel 41 by a predetermined interval (for example, about 100 mm). In this example, a pulley 43 having an outer diameter of 80 mm was used.

  In the ironing test, as shown in FIG. 5A, the optical fiber ribbon 10 is passed through the pulley 43 and then passed between the first and second horizontal mandrels 41 from the top in the vertical direction. Then, it passes over the vertical mandrel 42 and passes between the third and fourth horizontal mandrels 41 from the top in the vertical direction. In this way, the optical fiber ribbon 10 was passed between the mandrels 41 and 42 and moved downward in the longitudinal direction at a speed of 0.2 m / sec under a tension of 150 gf. Thereby, iron is added to the optical fiber ribbon 10.

  When the number of cores of the optical fiber ribbon 10 is less than 12 (for example, 4 cores and 8 cores), the optical fiber ribbon 10 is routed between the mandrels 41 and 42. May be changed as shown in FIG. More specifically, after straddling the vertical mandrel 42, it may be passed between the second and third horizontal mandrels 41 from the top in the vertical direction. Further, the tension applied to the optical fiber ribbon 10 may be changed to 100 gf.

  Observe the optical fiber ribbon 10 after the ironing test, confirm the number of the connecting portions 2 per 1 m peeled or broken in the longitudinal direction, and if the result is 2 or less, the result is good and OK, 3 or more If the result is NG, the result was bad and the result was NG.

  In the “Comprehensive Judgment” column in Tables 1 and 2, the above-mentioned “Optical Fiber Observation Results after Adhesion Strength Measurement”, “Single-core Separation”, “Removability of Connections”, and “Number of Debonds after Connection Test” ”Shows the overall results. More specifically, a sample in which good results were obtained for all items was determined to be OK, and a sample having at least one defective item was determined to be NG.

  Next, based on the results of Tables 1 and 2, the preferable ranges of the adhesion force A and the connecting portion tearing force S will be examined.

In Tables 1 and 2, in Samples 1-21 to 24 and Samples 2-20 to 23 in which the adhesion force A is 4.95 N / mm ² or 4.80 N / mm ² , the magnitude of the connecting portion tearing force S is set. Regardless, “the optical fiber observation result after the adhesion measurement” is defective (NG). This is because the adhesion force A between the colored layer 1c and the connecting portion 2 is too large, and peeling of the interface other than this interface and destruction of the coating layer 1b occur. Furthermore, in these samples, the result of “removability of connecting portion” is also poor. This is because the adhesion A between the colored layer 1c and the connecting portion 2 is too large, and the connecting portion 2 could not be peeled off within a predetermined number of times even when rubbed with abrasive paper.

On the other hand, Table 1 adhesion force A is 4.46N / mm ² The following sample 1-1～20, and adhesion force A of Table 2 is 4.30N / mm ² following samples 2-1～19, "adhesion “Optical fiber observation result after force measurement” is good (OK). This is because the adhesion force A between the colored layer 1c and the connecting portion 2 is not too large with respect to the adhesion force between the glass fiber 1a and the coating layer 1b, or between the coating layer 1b and the colored layer 1c, and peeling occurs at a desired interface. This is because of this. In addition, in these samples, the result of “removability of connecting portion” is also good. This is because the magnitude of the adhesion A is appropriate, and the resin piece of the connecting portion 2 can be easily removed with abrasive paper.

From the above results, when the optical fiber 1 having the colored layer outer diameter D of 252 μm is used, the adhesion force A is 4.46 N / mm ² or less, and the optical fiber 1 having the colored layer outer diameter D of 205 μm is used. In the case where the adhesion force A is 4.30 N / mm ² or less, the optical fiber 1 is not broken during the intermediate post-branching operation or the like, and the connecting portion 2 can be easily removed. Therefore, by setting the adhesion A to 4.30 N / mm ² or less, the optical fiber 1 is not broken during the intermediate post-branching operation or the like regardless of the colored layer outer diameter D of the optical fiber 1. In addition, the connecting portion 2 can be easily removed.

Next, the lower limit value of the adhesion force A will be examined. In the samples 1-1 to 1-4 in which the adhesion strength A in Table 1 is less than 0.38 N / mm ^{2 and} the samples 2-1 to 2-3 in Table 2 having a contact strength A less than 0.37 N / mm ² , Regardless of the size of S, the result of the ironing test is poor. This is because the contact force A is too small, and the connecting portion 2 is unexpectedly peeled off during the ironing test. From this, by setting the adhesion A to be 0.38 N / mm ² or more, it is possible to prevent the connecting portion 2 from being unexpectedly peeled regardless of the colored layer outer diameter D of the optical fiber 1.

From the above consideration, the optical fiber ribbon 10 preferably satisfies 0.38 [N / mm ² ] ≦ A ≦ 4.30 [N / mm ² ]. However, even within the range, there are samples in which the result of the comprehensive determination is defective (NG) depending on the magnitude of the connecting portion tearing force S. Hereinafter, the preferable range of the connecting portion tearing force S will be examined.

Samples 1-5 to 1-8 in Table 1 each have an adhesion force A of 0.38 N / mm ² and a connecting portion tearing force S in the range of 0.7 to 16.5 gf. These samples have good single core separation results. Among these samples, the sample 1-5 having a connecting portion tearing force S of 0.7 gf has a poor result of the ironing test, but the samples 1-6 to 1 having a connecting portion tearing force S of 1.0 gf or more. -8 The result of the ironing test is good.

Samples 1-9 to 1-12 in Table 1 each have an adhesion force A of 0.63 N / mm ² and a connecting portion tearing force S in the range of 0.6 to 15.0 gf. These samples have good single core separation results. Among these samples, Sample 1-9 having a connecting portion tearing force S of 0.6 gf has a poor result of the ironing test, but Samples 1-10 to 1 having a connecting portion tearing force S of 2.0 gf or more. The result of the -12 ironing test is good.

Samples 1-13 to 1-16 in Table 1 each have an adhesion force A of 1.55 N / mm ² and a connecting portion tearing force S in the range of 0.7 to 15.0 gf. These samples have good single core separation results. Among these samples, the sample 1-13 having the connecting portion tearing force S of 0.7 gf has a poor result of the ironing test, but the samples 1-14 to 1 having the connecting portion tearing force S of 1.1 gf or more. The result of the -16 ironing test is good.

Samples 1-17 to 1-20 in Table 1 each have an adhesion force A of 4.46 N / mm ² and a connecting portion tearing force S in the range of 0.6 to 17.0 gf. These samples have good single core separation results. Among these samples, although the result of the ironing test is poor for the sample 1-17 in which the connecting portion tearing force S is 0.6 gf, the samples 1-18 to 1 in which the connecting portion tearing force S is 1.0 gf or more The result of the -20 ironing test is good.

Samples 2-4 to 2-7 in Table 2 each have an adhesion force A of 0.37 N / mm ² and a connecting portion tearing force S in the range of 0.7 to 19.0 gf. Among these samples, the sample 2-4 having a connecting portion tearing force S of 0.7 gf has a poor result of the ironing test, but the sample 2-5 to 2 having a connecting portion tearing force S of 1.0 gf or more. The result of the -7 ironing test is good. Sample 2-7 having a connecting portion tearing force S of 19.0 gf has a poor single-core separation property, but samples 2-4 to 2-2- have a connecting portion tearing force S of 6.0 gf or less. No. 6 has a good single core separation result.

Samples 2-8 to 2-11 in Table 2 each have an adhesion force A of 0.85 N / mm ² and a connecting portion tearing force S in the range of 0.5 to 20.5 gf. Among these samples, the sample 2-8 having the connecting portion tearing force S of 0.5 gf is inferior in the result of the ironing test, but the samples 2-9 to 2 having the connecting portion tearing force S of 1.3 gf or more. The result of the -11 ironing test is good. Sample 2-11 having a connecting portion tearing force S of 20.5 gf has a poor single-core separation property, but samples 2-8 to 2-2- have a connecting portion tearing force S of 8.0 gf or less. No. 10 has a good single-core separation result.

Samples 2-12 to 2-15 in Table 2 each have an adhesion force A of 1.80 N / mm ² and a connecting portion tearing force S in the range of 0.6 to 15.0 gf. These samples have good single core separation results. Among these samples, the sample 2-12 having the connecting portion tearing force S of 0.6 gf has a poor result of the ironing test, but the samples 2-13 to 2 having the connecting portion tearing force S of 1.0 gf or more. -15 The result of the ironing test is good.

Samples 2-16 to 2-19 in Table 2 each have an adhesion force A of 4.30 N / mm ² and a connecting portion tearing force S in the range of 0.8 to 17.0 gf. These samples have good single core separation results. Among these samples, Sample 2-16 having a connecting portion tearing force S of 0.8 gf has a poor result of the ironing test, but Sample 2-17-2 having a connecting portion tearing force S of 1.0 gf or more. The result of the -19 ironing test is good.

To summarize the above, by setting 0.38 [N / mm ² ] ≦ A ≦ 4.30 [N / mm ² ] and 1.0 [gf] ≦ S, “the optical fiber observation result after the adhesion force measurement” Good results are obtained for each item of “connectivity removability” and “number of peeled connections after ironing test”.
In addition to the above range, by setting the connecting portion tearing force S to 17.0 gf or less, good results can be obtained for the “single-core separation property”.

As described above, the optical fiber ribbon 10 of the present embodiment includes a plurality of optical fibers 1 having the colored layer 1c and a plurality of connecting portions 2 that connect two adjacent optical fibers 1 to each other. I have. When the adhesion between the colored layer 1c and the connecting portion 2 is A [N / mm ² ] and the tearing force when tearing the connecting portion 2 is S [gf], 0.38 ≦ A ≦ 4.30. And by satisfying 1.0 ≦ S ≦ 17.0, the connecting portion 2 is not unexpectedly peeled off, and the optical fiber 1 can be easily connected and branched.

  Moreover, the resin piece of the connection part 2 adhering to the optical fiber 1 after single fiber separation can be easily removed by making the contact | adhesion force A and the connection part tearing force S into the said range. Accordingly, workability when connecting a connector or the like to the optical fiber 1 can be improved.

(Surface curing degree of colored layer 1c)
Next, preferable conditions for the degree of surface hardening of the colored layer 1c described above will be described. Here, a plurality of optical fiber ribbons 10 shown in Table 3 below were produced. When the colored layer 1c of the optical fiber 1 in Samples 3-1 to 3-9 shown in Table 3 is UV-cured, the surface hardening degree of the colored layer 1c is varied by changing the oxygen concentration.
Specifically, when the oxygen concentration during curing is increased, the surface curing is inhibited by oxygen inhibition. For this reason, the adhesive force A between the colored layer 1c and the connecting portion 2 is increased. That is, in samples 3-1 to 3-9, the larger the value of the adhesion force A, the lower the degree of cure of the surface of the colored layer 1c.

  The roller-colored stains shown in Table 3 indicate that the uncured colored layer 1c does not adhere to the alignment roller for feeding the optical fiber 1 after the colored layer 1c of the optical fiber 1 of each sample is cured with ultraviolet rays. It is the result of confirming. Specifically, after the colored layer 1c is cured to produce the optical fiber 1, the groove of the alignment roller is wiped with a paper wiper moistened with alcohol, and the paper wiper is checked for color transfer of the colored layer 1c. did. The case where there was no color transfer was indicated as “none”, and the case where the color transfer was confirmed visually was indicated as “present”.

  The scraping by the rollers shown in Table 3 is a result of observing the side surface of the optical fiber ribbon 10 of each sample and confirming that the colored layer 1c was not scraped when the optical fiber ribbon 10 was manufactured. . Specifically, the side surface of the optical fiber ribbon 10 immersed in the matching oil was observed with a microscope to confirm whether the colored layer 1c of each optical fiber 1 was scraped or peeled off. The case where the colored layer 1c was not scraped or the like was indicated as “none”, and the case where it was present was indicated as “present”.

The disconnection shown in Table 3 indicates whether or not the optical fiber 1 is disconnected when the optical fiber ribbon 10 is manufactured. Specifically, when the colored layer 1c is scraped when forming the connecting portion 2 into a tape, the die may be scraped and clogged, and the optical fiber 1 may be disconnected. When the disconnection of the optical fiber 1 occurs, “present” is indicated, and when there is no disconnection, “not present” is indicated.
In the comprehensive judgment shown in Table 3, OK (good judgment) is displayed when the results of roller coloring stains, scraping by rollers, and disconnection are all “None”, and any one of them is “Yes”. In this case, NG (defect determination) is displayed.

As shown in Table 3, in Samples 3-1 to 3-9, the adhesion strength A was changed in the range of 0.38 to 4.60 [N / mm ² ].
In Samples 3-1 to 3-5, roller coloring stains, scraping by rollers, and disconnection were not confirmed, and the overall determination was a good determination. This is because the surface hardening degree of the colored layer 1c is within an appropriate range, and the colored layer 1c is not scraped when the optical fiber 1 and the optical fiber ribbon 10 are manufactured.

Samples 3-6 to 3-9 were scraped by a roller, samples 3-8 to 3-9 were disconnected, and sample 3-9 was confirmed to be colored by rollers. For this reason, the comprehensive determination of samples 3-6 to 3-9 was a failure determination. This is because the colored layer 1c is scraped off during the production of the optical fiber 1 and the optical fiber ribbon 10 because the surface hardening degree of the colored layer 1c is too low.
From the above, by setting the adhesive force A [N / mm ² ] in the range of 0.38 ≦ A ≦ 2.50, the colored layer 1c of the colored layer 1c is produced when the optical fiber 1 and the optical fiber ribbon 10 are manufactured. The occurrence of scraping or the like can be suppressed. That is, the optical fiber ribbon 10 can be stably manufactured by adjusting the degree of surface hardening of the colored layer 1c so that the adhesion A is in the above range.

  The technical scope of the present invention is not limited to the above-described embodiments or examples, and various modifications can be made without departing from the spirit of the present invention.

For example, in the adhesion measurement shown in FIGS. 3A and 3B, the top 3 may have a groove at the center in the width direction. In this case, the connecting portion 2 provided at the second end E2 may be fixed to the inner wall of the groove portion of the top 3 with an adhesive 31 or the like.
In addition, since it is only necessary to measure the adhesion A at the interface between one optical fiber 1 and the connecting portion 2, the other optical fiber 1 that is not pulled out may be removed from the measurement sample in advance. However, in this case, when the other optical fiber 1 is removed, the interface between the optical fiber 1 to be measured and the connecting portion 2 is not affected.

  The physical properties of the colored layer 1c or the connecting portion 2 are not limited to those described in the examples, and may be changed as appropriate. For example, a material having a Young's modulus after curing of 750 to 1100 MPa, a tensile strength of 34.0 to 64.0 MPa, and a tensile elongation of 25 to 70% when measured based on JIS K 7113 as the connecting portion 2. It may be used.

  In addition, the constituent elements in the above-described embodiment can be appropriately replaced with known constituent elements without departing from the gist of the present invention, and the above-described embodiments and modifications may be appropriately combined.

  DESCRIPTION OF SYMBOLS 1 ... Optical fiber, 1a ... Glass fiber, 1b ... Coating layer, 1c ... Colored layer, 2 ... Connection part, 10 ... Optical fiber ribbon

Claims (2)

A plurality of optical fibers having a colored layer;
A plurality of connecting portions that connect the two adjacent optical fibers, and
The adhesion between the colored layer and the connecting portion is A [N / mm ² ],
When the tearing force when tearing the connecting portion is S [gf],
An optical fiber ribbon that satisfies 0.38 ≦ A ≦ 4.30 and 1.0 ≦ S ≦ 17.0.   The optical fiber ribbon according to claim 1, wherein the adhesion A satisfies 0.38 ≦ A ≦ 2.50.

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