Optical fiber ribbon core wire, die, and method for manufacturing optical fiber ribbon core wire

Abstract

This optical fiber ribbon comprises a plurality of coated optical fibers, and a common covering layer that integrally covers the plurality of coated optical fibers. In the longitudinal direction of the plurality of coated optical fibers, a plurality of intermittent coupling parts in each of which first coupling parts each comprising the common covering layer and non-coupling parts each formed by a cut in the common covering layer are alternately formed every two or more predetermined number of the coated optical fibers, and a plurality of continuous coupling parts in each of which a second coupling part comprising the common covering layer is continuously formed between the coated optical fibers other than the coated optical fibers between which the plurality of intermittent coupling parts are formed are formed. The number of the plurality of coated optical fibers is an even number. The plurality of intermittent coupling parts have a central intermittent coupling part in a central part in the width direction of the optical fiber ribbon, and the plurality of continuous coupling parts have, in two pairs of coated optical fibers sandwiching the central part therebetween in the width direction, an adjacent continuous coupling part between each pair of coated optical fibers. The thickness of the adjacent continuous coupling parts is larger than the thickness of the central intermittent coupling part, and larger than the thickness of the continuous coupling parts other than the adjacent continuous coupling parts.

Description

Technical Field

[0001] The present disclosure relates to an optical fiber ribbon core wire, a die for manufacturing the optical fiber ribbon core wire, and a method for manufacturing the optical fiber ribbon core wire using the die. This application claims priority based on Japanese Application No. 2020-169681 filed on October 7, 2020, and incorporates by reference all the descriptions described in the Japanese application.

Background Art

[0002] Patent Document 1 discloses a method for manufacturing an intermittently connected type optical fiber ribbon core wire (also referred to as an intermittent tape core wire) that can be separated into two optical fiber core wires. In the intermittent tape core wire, connecting portions and non-connecting portions are alternately formed in the longitudinal direction, and adjacent optical fiber core wires are intermittently connected, and it is described that periodic cuts penetrating in the thickness direction are made by a cutting roller.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

[0004] An optical fiber ribbon core wire according to one aspect of the present disclosure includes a plurality of optical fiber core wires, and the plurality of optical fiber core wires each entire circumference covering the plurality of optical fiber core wires and integrating singleAn optical fiber ribbon core wire having a common coating layer, wherein in the longitudinal direction of the plurality of optical fiber core wires, between every two or more predetermined numbers of the optical fiber core wires, a first connecting portion made of the common coating layer and a non-connecting portion formed by a cut in the common coating layer are alternately formed, a plurality of intermittent connecting portions are formed, and in the longitudinal direction, between optical fiber core wires other than those where the plurality of intermittent connecting portions are formed, a plurality of continuous connecting portions in which a second connecting portion made of the common coating layer is continuously formed are formed. the continuous connection part and the intermittent connection part are alternately arranged from the end portions in the width direction of the optical fiber ribbon core wire, The plurality of optical fiber core wires are an even number, the plurality of intermittent connecting portions have a central intermittent connecting portion at the central portion in the width direction of the optical fiber ribbon core wire, the plurality of continuous connecting portions have adjacent continuous connecting portions between each pair of optical fiber core wires among two pairs of optical fiber core wires sandwiching the central portion in the width direction, the thickness of the adjacent continuous connecting portions is thicker than the thickness of the central intermittent connecting portion, and is thicker than the thickness of the continuous connecting portions other than the adjacent continuous connecting portions.

[0005] A die according to one aspect of the present disclosure is a die for manufacturing an optical fiber ribbon core wire having a plurality of holes through which a plurality of parallel optical fiber core wires pass, the number of the plurality of holes is an even number, adjacent ones of the plurality of holes communicate with each other, a plurality of spaces between the holes are formed at the communication portions of the adjacent plurality of holes and sandwich the parallel surfaces of the plurality of optical fiber core wires, the plurality of spaces between the holes include a first opposing portion formed at the central portion in the width direction of the optical fiber ribbon core wire, a second opposing portion formed on both sides adjacent to the central portion in the width direction of the optical fiber ribbon core wire, and a third opposing portion formed in every two portions from the second opposing portion toward the end of the die. communicate The ratio of the opposing distance of the first opposing portion to the opposing distance of the second opposing portion is 1:1.1 or more, and the ratio of the opposing distance of the third opposing portion to the opposing distance of the second opposing portion is 1:1.03 or more.

[0006] A manufacturing method according to one aspect of the present disclosure is a method for manufacturing an optical fiber ribbon core wire using the die.

Brief Description of the Drawings

[0007] [[FIG. 1]] FIG. 1 is a perspective view of an optical fiber ribbon core wire according to an embodiment of the present disclosure. [[FIG. 2]] FIG. 2 is a cross-sectional view of an optical fiber ribbon core wire according to an embodiment of the present disclosure. [[FIG. 3]] FIG. 3 is a diagram for explaining a method of manufacturing an optical fiber ribbon core wire according to an embodiment of the present disclosure. [[FIG. 4]] FIG. 4 is a cross-sectional view of a die according to an embodiment of the present disclosure. [[FIG. 5]] FIG. 5 is a diagram for explaining the dimensions of the die described in FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

[0008] [PROBLEMS TO BE SOLVED BY THE PRESENT DISCLOSURE] In the production of an optical fiber ribbon core wire, when a tape resin serving as a common coating layer is applied, in the width direction of the optical fiber ribbon core wire, the shear stress at the center is larger than the shear stress at the end, and the resin pressure at the center is higher than the resin pressure at the end. Resin easily flows into the center, the gap between the optical fibers at the center widens, and more resin flows into the center, so that in the width direction, the thickness of the common coating layer at the center tends to be thicker than the thickness of the common coating layer at the end. For this reason, when producing an intermittent tape core wire by making a cut at a predetermined position between the optical fiber core wires of the optical fiber ribbon core wire as in Patent Document 1, it was difficult to stably make a cut between the optical fiber core wires at the center in the width direction. The difference between the resin pressure at the end and the resin pressure at the center in the width direction of the optical fiber ribbon core wire increases as the production speed of the optical fiber ribbon core wire increases. In order to increase the production speed of the optical fiber ribbon core wire, it has been desired to take measures so that the thickness between the optical fiber core wires where the cut is made does not increase.

[0009] An object of the present disclosure is to provide an optical fiber ribbon core wire, a die, and a method for manufacturing an optical fiber ribbon core wire suitable for manufacturing an intermittent tape core wire.

[0010] [Description of Embodiments of the Present Disclosure] First, the contents of the embodiments of the present disclosure will be listed and described. The optical fiber ribbon core wire according to the present disclosure is (1) a plurality of optical fiber core wires and the plurality of optical fiber core wires each entire circumference covered to the plurality of optical fiber core wires integrate single a common coating layer, and is an optical fiber ribbon core wire having a plurality of intermittent connection portions in which a first connection portion made of the common coating layer and a non-connection portion formed by a cut into the common coating layer are alternately formed between the optical fiber core wires for each of two or more predetermined numbers in the longitudinal direction of the plurality of optical fiber core wires; in the longitudinal direction, a plurality of continuous connection portions in which a second connection portion made of the common coating layer is continuously formed between the optical fiber core wires other than between the optical fiber core wires where the plurality of intermittent connection portions are formed are formed; the continuous connection part and the intermittent connection part are alternately arranged from the end portions in the width direction of the optical fiber ribbon core wire, the plurality of optical fiber core wires are an even number, the plurality of intermittent connection portions have a central intermittent connection portion at the central portion in the width direction of the optical fiber ribbon core wire, and the plurality of continuous connection portions have adjacent continuous connection portions between each pair of optical fiber core wires in two pairs of optical fiber core wires sandwiching the central portion in the width direction, the thickness of the adjacent continuous connection portion is thicker than the thickness of the central intermittent connection portion, and thicker than the thickness of the continuous connection portion other than the adjacent continuous connection portion. By adopting such a structure, it is possible to prevent the thickness of the central portion where the cut is made from becoming thick, and it becomes easier to make the cut.

[0011] The die according to the present disclosure is a die for manufacturing an optical fiber ribbon core wire having a plurality of holes through which a plurality of parallel optical fiber core wires pass, the number of the plurality of holes being an even number, adjacent ones of the plurality of holes communicating with each other, and at a communicating portion of adjacent ones of the plurality of holes, a plurality of spaces sandwiching a parallel plane of the plurality of optical fiber core wires are formed, and the plurality of spaces include a first opposing portion formed at a central portion in the width direction of the optical fiber ribbon core wire, a second opposing portion formed on both sides adjacent to the central portion in the width direction of the optical fiber ribbon core wire, and a third opposing portion formed in every two portions from the second opposing portion toward an end of the die. communicate The ratio of the opposing distance of the first opposing portion to the opposing distance of the second opposing portion is 1:1.1 or more, and the ratio of the opposing distance of the third opposing portion to the opposing distance of the second opposing portion is 1:1.03 or more. The die has a first opposing portion that forms a cut and a second opposing portion that does not form a cut with respect to an optical fiber ribbon core wire coated with a common coating layer. Since the ratio of the opposing distance of the first opposing portion to the opposing distance of the second opposing portion is 1:1.1 or more, the resin is more likely to stay at the location of the second opposing portion than at the location of the first opposing portion that opposes at a narrow interval. Therefore, at the location of the first opposing portion, it is possible to prevent the thickness of the common coating layer between the optical fiber core wires from becoming thick, and it becomes easy to make a cut at the central portion when manufacturing an intermittent tape core wire. Further, the die has a third opposing portion that does not form a cut, similar to the second opposing portion. Since the ratio of the opposing distance of the third opposing portion to the opposing distance of the second opposing portion is 1:1.03 or more, the resin is more likely to stay at the location of the second opposing portion than at the location of the third opposing portion that opposes at a narrow interval. As a result, the resin is more likely to accumulate at the location of the second opposing portion than at the location of the first opposing portion. Therefore, at the location of the first opposing portion, the thickness of the common coating layer between the optical fiber core wires can be made thinner more reliably.

[0012] ( 3)In one aspect of the method for manufacturing an optical fiber ribbon core wire of the present disclosure, it is a method for manufacturing an optical fiber ribbon core wire using the above die. By using this die, it becomes possible to form a thin common coating layer thickness between predetermined optical fiber core wires. Therefore, when manufacturing an intermittent tape core wire, it becomes easy to make a cut between the optical fiber core wires of the optical fiber ribbon core wire.

[0013] According to the above, it is possible to provide an optical fiber ribbon core wire suitable for manufacturing an intermittent tape core wire, a die for manufacturing this optical fiber ribbon core wire, and a method for manufacturing an optical fiber ribbon core wire using the die.

[0014] [Details of Embodiments of the Present Disclosure] Specific examples of the optical fiber ribbon core wire, die, and method for manufacturing an optical fiber ribbon core wire according to the embodiments of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to the following examples, but is shown by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. Also, as long as combinations of multiple embodiments are possible, the present disclosure includes combinations of any embodiments. In the following description, components with the same reference numerals in different drawings may be the same, and the description thereof may be omitted.

[0015] FIG. 1 is a perspective view of an optical fiber ribbon core wire according to an embodiment of the present disclosure. FIG. 2 is a cross-sectional view of an optical fiber ribbon core wire according to an embodiment of the present disclosure. The optical fiber ribbon core wire 10 is a plurality of, an even number, for example, 12 optical fiber core wires 11 (11a to 11l) arranged in parallel in a row in contact with each other, and an outer surface including upper and lower parallel surfaces is integrated over the entire length by a common coating layer 12 to form a tape shape. FIGS. 1 and 2 show the optical fiber ribbon core wire in a state where the optical fiber core wires 11 are in contact with each other, but the optical fiber core wires 11 may be separated without being in contact with each other.

[0016] The optical fiber core wire 11 is a single-core optical fiber. The optical fiber core wire 11 has a glass fiber 13, a protective coating 14, and a colored layer 15. The glass fiber 13 has a core 13a and a cladding 13b, and an outer diameter of 125 μm. The protective coating 14 covers the outer periphery of the glass fiber 13 and is, for example, an acrylate resin. The colored layer 15 covers the outer periphery of the protective coating 14 and has an outer diameter of around 255 μm. Note that the outer diameter of the glass fiber 13 and the outer diameter of the optical fiber core wire 11 are not limited to 125 μm and 255 μm respectively, and may be thinner, for example, around 100 μm and 200 μm respectively. The common coating layer 12 of the present embodiment is an ultraviolet curable resin or the like, but may also be a thermoplastic resin, a thermosetting resin, or the like. Further, the protective coating 14 may be composed of two layers.

[0017] The optical fiber ribbon core wire 10 according to the present embodiment is an intermittent tape core wire that periodically has a cut 17 penetrating in the thickness direction in the common coating layer 12 between two or more optical fiber core wires 11 for each predetermined number. That is, between the optical fiber core wires 11 provided with the cut 17, an intermittent connection portion 31 is formed in which a first connection portion 18 made of the common coating layer 12 and a non-connection portion made of the cut 17 penetrating in the thickness direction and without the common coating layer 12 are alternately formed over the longitudinal direction of the optical fiber ribbon core wire 10. Also, between the optical fiber core wires 11 not provided with the cut 17, a continuous connection portion 32 is formed in which a second connection portion 19 made of the common coating layer 12 is continuously formed over the longitudinal direction of the optical fiber ribbon core wire 10. Since the optical fiber ribbon core wire 10 is composed of an even number of wires, the center portion in the width direction of the optical fiber ribbon core wire 10 is where the spaces between the core wires of the optical fiber core wires 11 are located.

[0018] In the examples shown in FIGS. 1 and 2, a cut 17 is provided between every two optical fiber cores 11. More specifically, a cut 17 is provided in the common coating layer 12 between the optical fiber cores 11b and 11c, between the optical fiber cores 11d and 11e, between the optical fiber cores 11f and 11g, between the optical fiber cores 11h and 11i, and between the optical fiber cores 11j and 11k. Therefore, a plurality of intermittent connection portions 31 are formed between the optical fiber cores between the optical fiber cores 11b and 11c, between the optical fiber cores 11d and 11e, between the optical fiber cores 11f and 11g, between the optical fiber cores 11h and 11i, and between the optical fiber cores 11j and 11k, respectively. And a plurality of continuous connection portions 32 are respectively configured between the optical fiber cores between the optical fiber cores 11a and 11b, between the optical fiber cores 11c and 11d, between the optical fiber cores 11e and 11f, between the optical fiber cores 11g and 11h, between the optical fiber cores 11i and 11j, and between the optical fiber cores 11k and 11l.

[0019] In the common coating layer 12 between adjacent optical fiber cores 11, there are formed recesses 16a, 16aa, 16c formed by the depression of the common coating layer 12, and a flat portion 16b where the common coating layer 12 is flat in the width direction. The flat portion 16b is formed at the adjacent continuous connection portion 32' between each pair of optical fiber cores (a pair of optical fiber cores 11e and 11f and a pair of optical fiber cores 11g and 11h) sandwiching the central portion in the width direction of the optical fiber ribbon core. The recess 16aa is formed at the central intermittent connection portion 31' in the central portion in the width direction of the optical fiber ribbon core (between the optical fiber cores 11f and 11g). The recess 16a is formed at the intermittent connection portion 31 (between the optical fiber cores 11b and 11c, between the optical fiber cores 11d and 11e, between the optical fiber cores 11h and 11i, between the optical fiber cores 11j and 11k) other than the central portion in the width direction of the optical fiber ribbon core (between the optical fiber cores 11f and 11g). The recess 16c is formed at the continuous connection portion 32 (between the optical fiber cores 11a and 11b, between the optical fiber cores 11c and 11d, between the optical fiber cores 11i and 11j, and between the optical fiber cores 11k and 11l) other than both sides adjacent to the central portion in the width direction.

[0020] In this embodiment, the flat portion 16b is thicker than the recess 16aa and thicker than the recess 16c. The recess 16a is thicker than the recess 16aa. The recess 16a may be thicker or thinner than the recess 16c. Note that the thickness of the intermittent connection portion 31 (recess 16aa) represents the thickness of the connection portion where the common coating layer exists among the intermittent connection portions.

[0021] Note that in the case of the optical fiber ribbon core 10 with an outer diameter of 200 μm of the optical fiber core 11, it is preferable that the thickness d1 of the intermittent connection portion 31 at the central portion in the width direction of the optical fiber ribbon core 10 is 160 to 180 μm. In the case of the optical fiber ribbon core 10 with an outer diameter of 250 μm of the optical fiber core 11, it is preferable that the thickness d1 of the intermittent connection portion 31 at the central portion in the width direction of the optical fiber ribbon core 10 is 200 to 220 μm.

[0022] In this embodiment, the thickness d2 of the continuous connection portion 32 (the thickness of the flat portion 16b) on both sides adjacent to the center in the width direction of the optical fiber ribbon core wire 10 is greater than the thickness d1 of the intermittent connection portion 31 (the thickness of the concave portion 16aa) at the center in the width direction of the optical fiber ribbon core wire 10, and is also greater than the thickness d3 of the continuous connection portion 32 (the thickness of the concave portion 16c) in a portion other than both sides adjacent to the center in the width direction of the optical fiber ribbon core wire 10.

[0023] Generally, when the manufacturing speed of the optical fiber ribbon core wire is high, the coating between the optical fiber core wires at the center tends to be thicker than the coating between the optical fiber core wires at the end in the width direction. However, in the two pairs of optical fiber core wires sandwiching the center in the width direction of the optical fiber ribbon core wire 10, the thickness d2 of the adjacent continuous connection portion 32' without the notch 17 between each pair of optical fiber core wires is the central intermittent connection portion 31' with the notch 17 formed, which is thicker than the thickness d1 at the center in the width direction of the optical fiber ribbon core wire 10 and thicker than the thickness d3 of the continuous connection portion 31 outside both sides adjacent to the center in the width direction (outside the adjacent continuous connection portion 31'). By adopting such a structure, even if the shear stress at the center increases, it is possible to prevent the thickness d1 of the central intermittent connection portion 31' at the center in the width direction of the optical fiber ribbon core wire 10 from becoming thicker. Furthermore, when manufacturing the intermittent tape core wire, it becomes easier to make a notch between the optical fiber core wires at the center.

[0024] Next, a method for manufacturing an optical fiber ribbon core wire according to an embodiment of the present disclosure will be described. FIG. 3 is a diagram for explaining a method for manufacturing an optical fiber ribbon core wire according to an embodiment of the present disclosure. FIGS. 4 and 5 are cross-sectional views of a die according to an embodiment of the present disclosure. The manufacturing apparatus for the optical fiber ribbon core wire has a supply apparatus 100. Inside the supply apparatus 100, N (12 in this embodiment) reels 101 to 112 corresponding to the number of core wires of the optical fiber ribbon core wire 10, N dancer rollers 101a to 112a, and a guide roller 120 are provided. Each of the reels 101 to 112 has an optical fiber core wire 11 wound thereon. The optical fiber core wires 11 are respectively fed out from the reels 101 to 112, and a tension of several tens of gf is applied to each of them by the dancer rollers 101a to 112a, and they are arranged on one array surface when passing through the guide roller 120. The optical fiber core wires 11 are further bundled by an upper guide roller 130 and sent to a coating apparatus 200.

[0025] The optical fiber core wire 11 is inserted into the coating apparatus 200 and pulled with a predetermined tension from the downstream side. Thereby, the inserted optical fiber core wire 11 is guided by the nipple 210 to have a desired arrangement and is sent to the die 220. Inside the die 220, an ultraviolet curable resin as the common coating layer 12 shown in FIG. 1 is applied around the parallel optical fiber core wires 11. The ultraviolet curable resin is supplied from a pressure type resin tank 230. The 12 optical fiber core wires 11 coated with the ultraviolet curable resin are irradiated with ultraviolet rays in the ultraviolet irradiation apparatus 240 and cured. The cured ultraviolet curable resin becomes the common coating layer 12, and a 12-core optical fiber ribbon core wire 10 is formed.

[0026] The optical fiber ribbon core wire 10 cured by irradiation with ultraviolet rays by the ultraviolet irradiation device 240 is sent to a winding device 330 having a reel through a guide roller 250, a feeding capstan 310, a winding tension control dancer roller 320, and an intermittent processing device 400. The intermittent processing device 400 forms intermittent connection portions 31 of the optical fiber ribbon core wire 10, for example, by a cutting roller (not shown), and makes cuts that penetrate in the thickness direction and are periodic in the longitudinal direction in the common coating layer 12 between predetermined optical fiber core wires 11 of the optical fiber ribbon core wire 10. In the winding device 330, the optical fiber ribbon core wire 10 that has become an intermittent tape core wire is wound onto a reel through a guide. The winding tension of the entire optical fiber ribbon core wire 10 is, for example, several tens of gf to several hundreds of gf.

[0027] In this way, the optical fiber ribbon core wire 10 illustrated in FIG. 1 is manufactured. However, the coating device 200 may coat a thermoplastic resin instead of an ultraviolet curable resin as the resin for forming the common coating layer 12. In this case, the coating device 200 includes an extruder that extrudes the thermoplastic resin and a cooling device that cools the extruded resin. In any case, it is effective to cure the resin as soon as possible after passing through the die 220 in order to maintain the shape of the optical fiber ribbon core wire 10.

[0028] Next, the die 220 will be described. As shown in FIG. 4, the die 220 of the present embodiment has, for example, 12 holes 221 (221a to 221l) through which 12 optical fiber cores 11 pass, respectively, and a plurality of adjacent holes 221 communicate with each other. The number of holes is an even number. In the communication portion of a plurality of adjacent holes 221, a plurality of inter-hole spaces sandwiching the parallel plane of the plurality of optical fiber cores are formed. Note that the inter-hole space represents the interval in the connecting portion of a plurality of adjacent holes 221. The plurality of inter-hole spaces have a first opposing portion 222a-222a, a second opposing portion 222b-222b, and a third opposing portion 222c-222c. The first opposing portion 222a-222a is formed at the center in the width direction of the optical fiber ribbon core 10. The second opposing portion 222b-222b is formed on both sides adjacent to the center in the width direction of the optical fiber ribbon core 10, opposing at a wider interval than the first opposing portion 222a-222a in the thickness direction. The third opposing portion 222c-222c is formed at the connecting portion other than the center in the width direction of the optical fiber ribbon core 10 and both sides adjacent thereto (excluding the first opposing portion 222a-222a and the second opposing portion 222b-222b) and at positions other than every two or more predetermined numbers. By the die 220, in the optical fiber ribbon core covered with the common coating layer 12, the portion passing through the first opposing portion 222a-222a becomes the central intermittent connection portion 31', the portion passing through the second opposing portion 222b-222b becomes the adjacent continuous connection portion 32', and the portion passing through the third opposing portion 222c-222c becomes the continuous connection portion 32.

[0029] In the present embodiment, as shown in FIG. 5, a first opposing portion 222a-222a with the shortest opposing distance a is formed between the hole 221f and the hole 221g, and a second opposing portion 222b-222b with the longest opposing distance b is formed between the hole 221e and the hole 221f and between the hole 221g and the hole 221h. For the rest, for example, between the hole 221a and the hole 221b, between the hole 221c and the hole 221d, between the hole 221i and the hole 221j, and between the hole 221k and the hole 221l, a third opposing portion 222c-222c is formed, where the opposing distance c is longer than the opposing distance a of the first opposing portion 222a-222a and shorter than the opposing distance b of the second opposing portion 222b-222b.

[0030] More specifically, when the outer diameter of the optical fiber core 11 is 200 μm, the ratio of the facing distance a of the first facing portions 222a-222a to the facing distance b of the second facing portions 222b-222b is, for example, 1:1.6, and the ratio of the facing distance a of the first facing portions 222a-222a to the facing distance c of the third facing portions 222c-222c is set to, for example, 1:1.2. In this case, the ratio of the facing distance c of the third facing portions 222c-222c to the facing distance b of the second facing portions 222b-222b is 1:1.33. In this case, the ratio of the facing distance c of the third facing portions 222c-222c to the facing distance b of the second facing portions 222b-222b is 1:1.2.

[0031] Also, when the outer diameter of the optical fiber core 11 is 250 μm, the ratio of the facing distance a of the first facing portions 222a-222a to the facing distance b of the second facing portions 222b-222b is set to, for example, 1:1.8, and the ratio of the facing distance a of the first facing portions 222a-222a to the facing distance c of the third facing portions 222c-222c is set to, for example, 1:1.7. In this case, the ratio of the facing distance c of the third facing portions 222c-222c to the facing distance b of the second facing portions 222b-222b is 1:1.06. Even when the outer diameter of the optical fiber core 11 is 200 μm or 250 μm, the ratio of the facing distance a of the first facing portions 222a-222a to the facing distance b of the second facing portions 222b-222b is 1:1.1 or more. Similarly, even when the outer diameter of the optical fiber core 11 is 200 μm or 250 μm, the ratio of the facing distance c of the third facing portions 222c-222c to the facing distance b of the second facing portions 222b-222b is 1:1.03 or more.

[0032] The die 220 has a first opposing portion that is between the holes in the central part where a notch is formed, and a second opposing portion that is between the holes on both adjacent sides of the central part where no notch is formed, with respect to the optical fiber ribbon core wire covered with a common coating layer. The second opposing portion has a wider interval than the first opposing portion. Therefore, the resin pressure in the first opposing portion that opposes at the narrowest interval (opposing distance a) is lower than the resin pressure in the second opposing portion that opposes at a wider interval (opposing distance b), and the resin is more likely to stay at the location of the second opposing portion that opposes at a wider interval (opposing distance b) than at the location of the first opposing portion that opposes at the narrowest interval (opposing distance a). Thus, it becomes possible to prevent the thickness of the common coating layer between the optical fiber cores 11 from increasing at the location of this first opposing portion. Since the swelling of the resin in the first opposing portion can be suppressed, when manufacturing an intermittent tape core wire, it becomes easier to make a cut between the optical fiber cores 11 of the optical fiber ribbon core wire 10 at the thin location (the location of opposing distance a) of the common coating layer 12.

[0033] The die 220 has a third opposing portion where no notch is formed. The opposing distance of the third opposing portion has a narrower interval than the opposing distance of the second opposing portion. Therefore, the resin is more likely to stay at the location of the second opposing portion that opposes at a wider interval (opposing distance b) than at the location of the third opposing portion that opposes at a narrow interval (opposing distance c). As a result, the resin is more likely to accumulate at the location of the second opposing portion. Thus, at the location of the first opposing portion that opposes at the narrowest interval (opposing distance a), the thickness of the common coating layer between the optical fiber cores can be formed to be thinner more reliably.

[0034] As described above, regarding the optical fiber ribbon core wire according to the embodiment of the present disclosure, the case of two as two or more predetermined numbers has been described, but any other number may be used as long as it is an integer of two or more. Similarly, regarding the die, the case of two as two or more predetermined numbers has been described, but any other number may be used as long as it is an integer of two or more.

Explanation of reference numerals

[0035] 10…Optical fiber ribbon core wire, 11, 11a~11l…Optical fiber core wire, 12…Common coating layer, 13…Glass fiber, 13a…Core, 13b…Cladding, 14…Protective coating, 15…Coloring layer, 16a, 16aa, 16c…Recess, 16b…Flat part, 17…Cut (non-connected part), 18…First connection part, 19…Second connection part, 31…Intermittent connection part, 31’ …Central intermittent connection part, 32…Continuous connection part, 32’ …Adjacent continuous connection part, 100…Supply device, 101~112…Reel, 101a~112a…Dancer roller, 120…Guide roller, 130…Directly above guide roller, 200…Coating device, 210…Nipple, 220…Die, 221, 221a~221l…Hole, 222a, 222b, 222c…Opposing part, 230…Resin tank, 240…Ultraviolet irradiation device, 250…Guide roller, 310…Delivery capstan, 320…Take-up tension control dancer roller, 330…Take-up device, 400…Intermittent processing device.

Claims

1. A plurality of optical fiber cores, and a single common coating layer that covers the entire circumference of each of the plurality of optical fiber cores and integrates the plurality of optical fiber cores, the optical fiber ribbon core having, in the longitudinal direction of the plurality of optical fiber cores, a plurality of intermittent connection portions in which a first connection portion made of the common coating layer and a non-connection portion formed by a cut in the common coating layer are alternately formed between the optical fiber cores for each of two or more predetermined numbers; in the longitudinal direction, a plurality of continuous connection portions in which a second connection portion made of the common coating layer is continuously formed between the optical fiber cores other than between the optical fiber cores where the plurality of intermittent connection portions are formed, are formed, the continuous connection portions and the intermittent connection portions are alternately arranged from the end portions in the width direction of the optical fiber ribbon core, the plurality of optical fiber cores are an even number, the plurality of intermittent connection portions have a central intermittent connection portion at the central portion in the width direction of the optical fiber ribbon core, the plurality of continuous connection portions have adjacent continuous connection portions between each pair of optical fiber cores among two pairs of optical fiber cores sandwiching the central portion in the width direction, an optical fiber ribbon core in which the thickness of the adjacent continuous connection portion is thicker than the thickness of the central intermittent connection portion and thicker than the thickness of the continuous connection portion other than the adjacent continuous connection portion.

2. A die for manufacturing an optical fiber ribbon core having a plurality of holes through which a plurality of parallel optical fiber cores pass, the number of the plurality of holes is an even number, the adjacent plurality of holes communicate with each other, at the communication portion of the adjacent plurality of holes, a plurality of spaces between the holes sandwiching the parallel plane of the plurality of optical fiber cores are formed, Between the plurality of holes, there are a first opposing portion formed at the center in the width direction of the optical fiber ribbon core wire, a second opposing portion formed on both sides adjacent to the center in the width direction of the optical fiber ribbon core wire, and a third opposing portion formed in every two of the communication portions from the second opposing portion toward the end of the die. The ratio of the opposing distance of the first opposing portion to the opposing distance of the second opposing portion is 1:1.1 or more. A die in which the ratio of the opposing distance of the third opposing portion to the opposing distance of the second opposing portion is 1:1.03 or more.

3. A method for manufacturing an optical fiber ribbon core wire using the die according to claim 2.

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