JPH02208242A - Production resin-coated optical fiber - Google Patents

Abstract

PURPOSE:To make the surface of resin-coated optical fiber uniform and not to let elongated strain readily occur by vibrating the surface of coated layer while coating optical fiber with a resin and forming uneven states on the surface of coated layer. CONSTITUTION:Plural element wires 1 of optical fiber are sent from a feeder 2 of element wire of optical fiber, arranged in a row and introduced to a tape material coating device 3. Then the element wires 1 are passed through a vibrating device 4 while being coated with a coating resin such as ultraviolet- curing resin of urethane acrylate base by a device 3 and the coating resin applied to the outer periphery of the element wires 1 is vibrated to form uneven states on the surface. Then the coating resin is cured by a tape material curing device 5 to give a tape-like core wire 6 of optical fiber. Then the core wire 6 is wound through accumulator 7, a capstan 8 and a dancer 9 around a winder 10 to produce resin-coated optical fiber.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a resin-coated optical fiber, and more particularly to a method for manufacturing a resin-coated optical fiber that forms a coating layer with excellent bending properties.

[Conventional technology]

FIG. 4 shows a cross-sectional structure of a ribbon spacer cable using optical fibers. 41 is a rod-shaped grooved spacer provided with a groove 42 on the outer periphery, and usually at least one groove 42 is provided with a groove 42.
A light beam having a structure (hereinafter referred to as a spacer structure) containing a laminate in which resin-coated optical fibers (hereinafter referred to as optical fibers) are arranged in rows and are laminated with tape-shaped optical fiber cores that are collectively coated. The fiber unit 46 has excellent characteristics such as being able to achieve high density and being easy to connect because it can be connected optical fiber by optical fiber. 4 in Figure 4
4 is a press, 45 is a cable 7-base, and 46 is a tensile strength member.

When an optical fiber unit with a spacer structure is bent, elongation strain occurs in the optical fiber located on the outside of the bend.
Compressive strain occurs in the optical fiber located in the bent inner portion.

Since elongation strain promotes the elongation of cracks on the optical fiber surface,
Continuing to apply large strain for a long period of time is not desirable from the viewpoint of long-term reliability. Furthermore, since the spacer-structured optical fiber unit has a structure in which the optical fiber core wire laminate is wound, lateral pressure is applied to the optical fiber when elongation strain occurs. Therefore, even though the transmission loss increases due to lateral pressure, it is necessary to suppress the elongation strain to a small level. K suppresses bending distortion
For example, as disclosed in Japanese Unexamined Patent Publication No. 62-89915, there is an example in which the outermost coating layer of an optical fiber is made of a material having a coefficient of static friction of 0.9 or less. Further, as a method for forming the outermost coating layer using a material having a coefficient of static friction of 0.9 or less, for example, Japanese Patent Publication No. 62-42247 discloses a method of applying powder around an optical fiber.

[Problem to be solved by the invention]

The conventionally proposed method of coating an optical fiber with an outermost coating layer made of fine powder of a material with a coefficient of static friction below a certain value increases the number of manufacturing steps for the optical fiber, lowers productivity, and increases manufacturing costs. There is a problem that not only is the price high, but there are restrictions on handling in order to prevent the coated fine powder from falling off in the next process.

Further, it is not easy to uniformly apply fine powder to the surface of the optical fiber coating material, and there is also a problem in terms of working environment conditions in which dust is likely to be generated.

Furthermore, the present situation is that there is no suitable material that exhibits sufficiently low friction without any treatment on the surface of the coating material.

The present invention solves the conventional problems and creates a resin-coated optical fiber in which the surface of the coated optical fiber is made uniform and has a structure that does not easily suffer from elongation strain without applying fine powder or the like to the coated surface of the optical fiber. The purpose of this invention is to provide a method for manufacturing.

[Means to solve the problem]

In order to achieve the above object, the present invention provides a method for manufacturing a resin-coated optical fiber by coating an optical fiber with a resin.
The step of coating the optical fiber with resin is performed by vibrating the surface of the outer coating layer applied to the optical fiber while applying the resin to the optical fiber, or immediately after coating the optical fiber with the resin, to vibrate the surface of the outer coating layer. It is characterized by including a step of forming an uneven shape.

Also, as a step of vibrating the surface of the outer peripheral coating layer applied to the optical fiber and forming the surface of the outer peripheral coating layer into an uneven shape, a step of vibrating the outer peripheral coating layer applied to the optical fiber while applying resin to the optical fiber. is effective by applying a process of vibrating the resin coating device through which the optical fiber passes, and a process of vibrating the surface of the outer coating layer applied to the optical fiber immediately after coating the optical fiber with resin is effective. It is effective to apply a step of blowing an air stream onto the surface of the outer peripheral coating layer applied to the optical fiber immediately after the optical fiber passes through a resin coating device and the optical fiber is coated with resin.

Furthermore, the optical fiber to which the manufacturing method of the present invention is applied includes:
It is effective to apply a multicore resin-coated optical fiber in which a plurality of optical fibers are coated with a common coating.

[Effect]

In the method for manufacturing a resin-coated optical fiber of the present invention, when applying a coating resin to a bare optical fiber or a resin-coated optical fiber, the outer periphery of the optical fiber is applied while the resin is being applied or immediately after the resin coating is applied. Since unevenness is formed on the surface of the outer coating layer of a resin-coated optical fiber by a manufacturing method that includes a step of vibrating the surface of the coating layer, surface treatment of the outer coating layer using other materials, such as fine powder, is required. There are no problems such as an increase in the number of manufacturing steps, a decrease in productivity, or an increase in manufacturing costs, which are required in the method of coating the product, and there are no restrictions on handling. Furthermore, the surface of the outer peripheral coating layer can be uniformly made to have low friction, and there is no adverse effect of dust generation on the working environment conditions.

In addition, a similar method for forming the surface of the outer peripheral coating layer into an uneven shape is to use a resin coating die with an uneven hole shape. It is not easy to do so, and when actually manufactured, it is inevitable that vertical streaks will appear in the longitudinal direction.

Since the vibration method of the present invention allows the amplitude and period of vibration to be adjusted, fine irregularities can be formed on the resin-coated surface in both the longitudinal direction and the circumferential direction. Examples will be described below based on the drawings.

〔Example〕

FIGS. 1a and 1b are process diagrams of an embodiment of the resin-coated optical fiber manufacturing method of the present invention.

FIG. 1a shows a plurality of optical fiber strands 1 supplied from an optical fiber strand feeder 2 arranged in, for example, a row, and passed through a tape material coating device 3 all at once, and coated with tape material, for example, coated resin. While coating, the coating resin applied to the outer periphery is vibrated by a vibration device 4 to form an uneven surface, and in this embodiment, the coating resin is cured by a two-step tape material curing device 5. A goobed optical fiber core 6 is produced, and an accumulator 7, a capstan 8. This is an embodiment of a method for manufacturing a tape core, which is comprised of each process of winding up a tape cable through a dancer 9 and onto a winding machine 10.

In Figure 1, a base material 11 is drawn in a heating furnace 12, and the outer diameter of the optical fiber is measured by an outer diameter measuring device 13.The optical fiber is coated with resin through a resin coating device 14 while being controlled. , vibrating the outer peripheral coating layer with a vibration device 15 to form an uneven surface on the outer peripheral coating layer, and curing the coating resin with the surface formed in an uneven shape with a curing device 16;
This is an example of a method for manufacturing an optical fiber strand, which is comprised of steps of producing a resin-coated optical fiber strand and winding it onto a winder 18 via a guide roller 17.

FIG. 2a shows a main part configuration of an embodiment of a vibrating device applied to the vibration step in the resin coating step of the manufacturing method of the embodiment shown in FIG. 1a. -Multiple optical fiber strands 2 arranged in a row
2, the resin coating device 20 is a die vibrating type that vibrates in the direction of the arrow while applying the resin of the tape material all at once, and the resin coated optical fiber tape has irregularities formed on the outer layer resin coating surface. A core wire 211 is produced.

Further, FIG. 2 shows the main part configuration of an embodiment of a vibrating device applied to the vibration step in the resin coating step of the manufacturing method of the embodiment of FIG. 1. Immediately after coating the outer layer resin coated surface of the resin coated optical fiber 21 which has been resin coated by the resin coating device, the outer layer resin coated surface is coated by a jet air flow method in which a jet stream gas 24 is sprayed from a jet nozzle 26. An optical fiber having irregularities formed thereon is produced.

FIG. 3a shows an example of a tape core wire 30 manufactured by the manufacturing method shown in FIG. 1a and the die-vibrating resin coating process shown in FIG. fiber 3
2 are arranged in four-core rows, and the outer periphery is collectively covered with a coating layer 66 having an uneven surface.

FIG. 3 shows an example of an optical fiber 34 manufactured by the manufacturing method shown in FIG. 1 using the jet stream type resin coating process shown in FIG. Covering layer 3
It has a structure in which a glass 31 is covered with glass 31.

Hereinafter, specific examples of tape core wires and optical fiber strands experimentally produced by the manufacturing method of the present invention, shown in Figure 41a and Figure 1, will be described.

Example 1: A urethane acrylate-based ultraviolet curable resin was applied to the outer periphery of four optical fibers arranged in a row using a die vibration type vibration device illustrated in FIG. A sample of the tape core wire having the structure shown in Figure 6a was fabricated.

As a comparative example, four optical fibers 52 having the same dimensions and structure as the sample according to the present invention and coated on glass 51 shown in FIG. Conventional Example 2 was prepared.

Samples according to the present invention and conventional examples 1 and 2 as comparative examples
Figure 4 shows the results of measuring the coefficient of static friction on the surface of each of the tape cores and the transmission characteristics after making the spacer cable shown in Figure 4 using the sample and Conventional Example 1 and Conventional Example 2, respectively. It is shown in Table 1. The prepared sample, conventional example 1. Conventional Example 2 is a product with a length of 1500 m, and the transmission characteristics after being made into a cable are as follows: Light wavelength λ = 1.5
This is a measured value at 5 μm.

Table 1 As can be seen from the results shown in Table 1, the samples manufactured according to the present invention have uniform unevenness formed on the coating resin surface over the entire length, have a small coefficient of static friction, and have a high transmission rate after being made into cables. The results were good with little loss. There are also no particular problems in handling.

On the other hand, Conventional Example 1 which was not subjected to surface treatment as a comparative example had a large friction coefficient, and a slight increase in transmission loss was observed after being made into a cable. In addition, Conventional Example 2, in which Merck powder was applied to the coating surface, had a small friction coefficient and no increase in transmission loss was observed after being made into a cable, which was good. However, when applying talc,
The process of applying it uniformly to the surface was difficult, and in addition, dust was generated, creating problems in the working environment.

Example 2: A urethane acrylate-based ultraviolet curable resin was used as the coating resin for the optical fiber, and the resin was formed around the outer periphery of a bare glass fiber with a diameter of 125 μmφ to a diameter of about 240 to 250 μmφ, and the jet shown in FIG. Using an airflow vibrator, a sample of an optical fiber having the structure shown in Figure 3 was fabricated.

As a comparative example, an optical fiber strand 54 having a coating layer 56 applied to a glass 51 shown in FIG. , Conventional Example 2 in which talc powder was applied to the coated surface by another conventional method were prepared.

The static friction coefficient and transmission characteristics of the sample according to the present invention, Conventional Example 1, and Conventional Example 2 were investigated.

The results are shown in Table 2. The prepared sample and conventional example 1. Conventional Example 2 was a product with a length of 2000 m, and the transmission characteristics were measured at a light wavelength λ = 1.55 μm, and the transmission characteristics were measured at temperatures of 26°C and -40°C.

As can be seen from the results in Table 2, the samples produced according to the present invention have uniform irregularities on the surface of the wadding-coated resin over the entire length, have a small coefficient of static friction, and have excellent bending properties. There is. Furthermore, the transmission characteristics are good from room temperature to low temperatures, and transmission characteristics equivalent to those of the conventional example are obtained. Conventional example 1 had a large coefficient of static friction and poor bending properties, and conventional example 2
As in Example 1, the difficulty in applying talc powder,
Work environment problems were observed due to dust generation.

Furthermore, in this example, the transmission characteristics due to tension fluctuations during winding of the optical fiber strands were investigated for a sample prototyped according to the present invention and Conventional Example 1. The results are shown in Table 6.

The manufacturing method for the third table is that in the process of coating the optical fiber with resin, when applying the coating resin, unevenness is formed on the outer periphery of the coating layer, so that the coefficient of static friction is small and the transmission loss after being made into a cable is reduced. This method is highly effective as a method for manufacturing resin-coated optical fibers that can realize an optical fiber unit structure with less noise, no increase in manufacturing steps, and has excellent productivity and transmission characteristics.

As can be seen from Table 6, in Conventional Example 1, when tension fluctuation occurs, local distortion remains in the optical fiber, resulting in poor transmission characteristics. On the other hand, it was confirmed that in the sample manufactured according to the present invention, no strain remained in the optical fiber even when tension fluctuation occurred, and there was no problem in terms of transmission characteristics.

〔Effect of the invention〕

As explained above, the resin-coated optical fiber of the present invention

[Brief explanation of the drawing]

FIGS. 1a and 1b are process diagrams of an embodiment of the resin-coated optical fiber manufacturing method of the present invention, FIGS. 2a and 2b are main part configuration diagrams of an embodiment of a vibrating device applied to the vibration process of the present invention, and FIG. 6 a, b
Fig. 4 is a cross-sectional structural diagram of a tape core spacer cable using an optical fiber, and Fig. 5 a and b are conventional manufacturing methods. FIG. 2 is a structural diagram of an example of a resin-coated optical fiber manufactured by the method. 1, 22.34.54...Optical fiber wire, 2...
Optical fiber wire feeder, 6... tape material coating device, 4
．． 15 optical fiber core wire, 7... accumulator, 8...
...Capstan, 9...Dancer, 10,18...
Winding machine, 11...Base material, 12...Heating furnace, 16...
・Outer diameter measuring device, 14, 20...Resin coating device, 16
...Curing device, 17...Guide roller, 21...
Resin-coated optical fiber, 211... Resin-coated optical fiber tape core, 26... Shed nozzle, 24... Gas, 30.50... Tape core, 31.51... Glass, 52.52 ...Optical fiber, 33, 53... Covering layer, 41... Grooved spacer,
42...Groove, 46...Optical fiber unit, 44...
... Presser winding tape, 45 ... Cable north, 46.
... Tensile body patent applicant Sumitomo Electric Industries Co., Ltd. Representative Patent attorney Gobe Tamamushi

Claims (5)

[Claims] (1) In a method of manufacturing a resin-coated optical fiber by coating an optical fiber with a resin, the step of coating the optical fiber with a resin includes forming an outer peripheral coating layer on the optical fiber while applying a resin to the optical fiber. A method for manufacturing a resin-coated optical fiber, comprising the step of vibrating the surface to form an uneven surface of the outer peripheral coating layer. (2) The step of vibrating the surface of the outer peripheral coating layer applied to the optical fiber to form an uneven surface of the outer peripheral coating layer,
2. The method of manufacturing a resin-coated optical fiber according to claim 1, further comprising the step of vibrating a resin coating device through which the optical fiber passes. (3) In the method of manufacturing a resin-coated optical fiber by coating an optical fiber with a resin, the step of coating the optical fiber with resin includes adding a peripheral coating layer to the optical fiber immediately after coating the optical fiber with the resin. A method for manufacturing a resin-coated optical fiber, comprising the step of vibrating the surface to form an uneven surface of the outer peripheral coating layer. (4) The step of vibrating the surface of the outer peripheral coating layer applied to the optical fiber and forming the surface of the outer peripheral coating layer into an uneven shape is performed by passing the optical fiber through a resin coating device and coating the optical fiber with resin. 4. The method of manufacturing a resin-coated optical fiber according to claim 3, further comprising the step of immediately thereafter blowing an air stream onto the surface of the outer peripheral coating layer applied to the optical fiber. (5) The method for manufacturing a resin-coated optical fiber according to claim 1 or 6, wherein the resin-coated optical fiber is a multicore resin-coated optical fiber in which a plurality of optical fibers are coated in a common manner.