JPH02233537A - Production of optical fiber core - Google Patents
Production of optical fiber coreInfo
- Publication number
- JPH02233537A JPH02233537A JP1054091A JP5409189A JPH02233537A JP H02233537 A JPH02233537 A JP H02233537A JP 1054091 A JP1054091 A JP 1054091A JP 5409189 A JP5409189 A JP 5409189A JP H02233537 A JPH02233537 A JP H02233537A
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- coating
- type silicone
- silicone resin
- resin
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 40
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 239000011248 coating agent Substances 0.000 claims abstract description 29
- 238000000576 coating method Methods 0.000 claims abstract description 29
- 229920002050 silicone resin Polymers 0.000 claims abstract description 21
- 229920005992 thermoplastic resin Polymers 0.000 claims abstract description 17
- 238000000034 method Methods 0.000 claims description 4
- 229920005989 resin Polymers 0.000 abstract description 7
- 239000011347 resin Substances 0.000 abstract description 7
- 238000009987 spinning Methods 0.000 abstract description 7
- 229920001187 thermosetting polymer Polymers 0.000 abstract description 4
- JHWNWJKBPDFINM-UHFFFAOYSA-N Laurolactam Chemical compound O=C1CCCCCCCCCCCN1 JHWNWJKBPDFINM-UHFFFAOYSA-N 0.000 abstract description 3
- 229920000299 Nylon 12 Polymers 0.000 abstract description 3
- 239000004677 Nylon Substances 0.000 abstract description 2
- 229920000571 Nylon 11 Polymers 0.000 abstract description 2
- 239000004721 Polyphenylene oxide Substances 0.000 abstract description 2
- 229920001778 nylon Polymers 0.000 abstract description 2
- -1 polybutylene terephthalate Polymers 0.000 abstract description 2
- 229920001707 polybutylene terephthalate Polymers 0.000 abstract description 2
- 229920006380 polyphenylene oxide Polymers 0.000 abstract description 2
- 239000000126 substance Substances 0.000 abstract description 2
- 230000003287 optical effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 238000001125 extrusion Methods 0.000 description 3
- 239000000835 fiber Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 210000002445 nipple Anatomy 0.000 description 3
- 238000001816 cooling Methods 0.000 description 2
- 238000004132 cross linking Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 239000004696 Poly ether ether ketone Substances 0.000 description 1
- JUPQTSLXMOCDHR-UHFFFAOYSA-N benzene-1,4-diol;bis(4-fluorophenyl)methanone Chemical compound OC1=CC=C(O)C=C1.C1=CC(F)=CC=C1C(=O)C1=CC=C(F)C=C1 JUPQTSLXMOCDHR-UHFFFAOYSA-N 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000002074 melt spinning Methods 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 229920002492 poly(sulfone) Polymers 0.000 description 1
- 229920002530 polyetherether ketone Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 239000011253 protective coating Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
- C03C25/10—Coating
- C03C25/104—Coating to obtain optical fibres
- C03C25/106—Single coatings
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、通信用光ケーブル、光コード、光テープ心線
等に用いられる光ファイバ心線の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for manufacturing optical fibers used for communication optical cables, optical cords, optical tapes, etc.
従来、光ファイバ心線は紡糸工程で得られた光ファイバ
裸線に、紫外線硬化樹脂（ＵＶ樹脂）或は熱硬化性シリ
コーン樹脂などからなる一次被覆を設けて光ファイバ素
線をつ《り、次に、この素線に、押出機によってナイロ
ン１２などの熱可塑性樹脂からなる二次１ｋｍを設けて
製造されている。Conventionally, optical fiber cores are produced by applying a primary coating made of ultraviolet curable resin (UV resin) or thermosetting silicone resin to bare optical fibers obtained in a spinning process, and then forming optical fibers. Next, this strand is manufactured by providing a 1 km secondary layer made of a thermoplastic resin such as nylon 12 using an extruder.
これは、光ファイバ課線上に直接押出被ｌによって二次
被覆を設けようとすると、光ファイバ裸線が押出機のニ
ップルに接触し、この接触によって光ファイバ課線表面
に微少な傷が生じ、光ファイバ強度の低下を招《ためで
あり、紫外線硬化樹脂や熱硬化性シリコーン樹脂からな
る一次肢覆はこのような傷の発生を防止するための保護
用被覆として機能するものである。このため、従来は通
常径１２５μｍの光ファイバ裸線に厚さ約６２μｍの上
記一次被覆を設けて、外径２５０μｍとし、この上に上
記二次被覆を設けて仕上径０．９ｍｍの光ファイバ心線
としている。This is because when attempting to provide a secondary coating on the optical fiber section by direct extrusion, the bare optical fiber comes into contact with the nipple of the extruder, and this contact causes minute scratches on the surface of the optical fiber section. This is to reduce the strength of the optical fiber, and the primary cover made of ultraviolet curing resin or thermosetting silicone resin functions as a protective coating to prevent the occurrence of such scratches. For this reason, conventionally, a bare optical fiber with a diameter of 125 μm is coated with the above-mentioned primary coating with a thickness of about 62 μm to give an outer diameter of 250 μm, and then the above-mentioned secondary coating is provided on top of this to create an optical fiber core with a finished diameter of 0.9 mm. It is a line.
ところで、近時光ケーブルなどにおいては、大容量化、
細径化の要望があり、光ファイバ心線自体を細径化する
必要が生じてきている。By the way, in recent years optical cables have increased in capacity,
There is a demand for a smaller diameter, and it has become necessary to reduce the diameter of the optical fiber itself.
このためには、上述の一次被覆および二次被覆の厚さを
薄くせねばならないが、一次彼覆の厚さを薄くすると二
次被覆時の押出機のニップルでの擦過傷の発生を十分に
防止することが困難となり、光ファイバ心線としての機
械的強度が低下する恐れがある。To achieve this, it is necessary to reduce the thickness of the primary coating and secondary coating described above, but reducing the thickness of the primary coating sufficiently prevents scratches from occurring at the nipple of the extruder during the secondary coating. It becomes difficult to do so, and there is a possibility that the mechanical strength of the coated optical fiber may decrease.
一方、光ファイバ母材の溶融紡糸から二次被覆形成まで
の一連の工程を連続化（タンデム化）し、製造効率を高
める必要もある。On the other hand, it is also necessary to increase manufacturing efficiency by making the series of steps from melt spinning of the optical fiber preform to forming the secondary coating continuous (tandem).
この発明では、溶融紡糸された光ファイバ裸線にラダー
型シリコーン樹脂からなる被覆を設けたのち、引き続い
て熱可塑性樹脂の押出しによる被覆を行うことにより、
上記課題を解決するようにした。In this invention, a coating made of ladder-type silicone resin is provided on a melt-spun bare optical fiber, and then a coating is performed by extrusion of a thermoplastic resin.
I tried to solve the above problem.
第１図は、本発明の光ファイバ心線の製造方法に用いる
装置の一例を示す概略図で、図中符号ｌは、光ファイバ
母材である。この母材ｌは、紡糸炉．２において、先フ
ァイバ裸線３に紡糸される。FIG. 1 is a schematic diagram showing an example of an apparatus used in the method for producing a coated optical fiber according to the present invention, and reference numeral l in the figure represents an optical fiber preform. This base material l was prepared in a spinning furnace. 2, the tip fiber is spun into a bare wire 3.
この紡糸炉２より引出された裸線３は、ただちに未硬化
の液状のラダー型シリコーン樹脂４ａが満たされたコー
ティングポット４に導入され、その表面に該樹脂液が塗
布された状態で、架橋筒５に導かれ、架橋され、ラダー
型シリコーン樹脂が肢覆されて光ファイバ素線６となる
。このラダー型シリコーン樹脂からなる一次被覆の厚さ
は、通常１〜１０μｍの範囲とされる。The bare wire 3 drawn out from the spinning furnace 2 is immediately introduced into a coating pot 4 filled with an uncured liquid ladder-type silicone resin 4a, and with the resin liquid applied to the surface of the coating pot 4, a cross-linked tube is coated. 5, is crosslinked, and the ladder-type silicone resin is turned over to form an optical fiber 6. The thickness of this primary coating made of ladder-type silicone resin is usually in the range of 1 to 10 μm.
ここでのラダー型シリコーン樹脂とは、例えば次の（［
）式に示したような化学構造を有する熱硬化型樹脂であ
る。Here, the ladder-type silicone resin is, for example, the following ([
) It is a thermosetting resin having the chemical structure shown in the formula.
このラダー型シリコーン樹脂は、オルガノシルセスキオ
キサンオリゴマーを加熱縮合して各ラダー（梯子）端お
よびラダー間を橋かけし、ＳＯ−Ｓｉ結合を成長させて
得られたポリオルガノシルセスキオキサンである。なお
、ラダー型シリコーン樹脂には、上記（１）式に示した
構造の池、側鎖のメチル基とフェニル基のモル比を種々
変えた構造を有するものを使用してもよく、これによつ
て縮合硬化したラダー型シリコーン樹脂の硬度や耐熱性
を適宜調節することが可能である。This ladder-type silicone resin is a polyorganosilsesquioxane obtained by heating and condensing organosilsesquioxane oligomers to bridge each ladder end and between the ladders and grow SO-Si bonds. be. Note that the ladder-type silicone resin may have the structure shown in formula (1) above, and a structure in which the molar ratio of the methyl group to the phenyl group in the side chain is varied. It is possible to adjust the hardness and heat resistance of the ladder type silicone resin which is condensed and cured.
この素線６は、引き続いて熱可塑性樹脂からなる被覆を
行う押出機７に導かれ、溶融した熱可塑性樹脂により二
次被覆された後冷却筒８によって冷却され、光ファイバ
心線９が得られる。ここでの熱可塑性樹脂としては、従
来のナイロンｌ２の他にナイロン１１ナイロン６−１０
、ポリフェニレンオキサイト、ポリブチレンテレフタレ
ート、ポリサルホン、ＰＥＥＫなどのエンジニアリング
プラスチックが用いられる。This strand 6 is then led to an extruder 7 that coats it with a thermoplastic resin, and after being secondly coated with a molten thermoplastic resin, it is cooled by a cooling tube 8 to obtain an optical fiber core 9. . In addition to the conventional nylon 12, the thermoplastic resin used here includes nylon 11, nylon 6-10,
, polyphenylene oxide, polybutylene terephthalate, polysulfone, PEEK, and other engineering plastics are used.
このように光ファイバ心線９は、タンデムに配置されて
いる紡糸炉２、ラダー型シリコーン樹脂コーティングポ
ット４および押出機７を通って連続的に製造され、中間
ロールｌＯを通って巻取ロール１ｌに巻取られる。なお
、第２図（ａ）（ｂ）（Ｃ）はそれぞれ、上記説明にお
ける光ファイバの裸線３、素線６、心線９の横断面を示
す図である。In this way, the optical fiber core 9 is continuously manufactured through the spinning furnace 2, the ladder-type silicone resin coating pot 4, and the extruder 7, which are arranged in tandem, and then passes through the intermediate roll 1O to the take-up roll 1L. It is wound up. Note that FIGS. 2(a), 2(b), and 2(C) are diagrams showing cross sections of the bare wire 3, the strand 6, and the core wire 9 of the optical fiber in the above description, respectively.
上記光ファイバ心線の製造方法においては、光ファイバ
裸線上に耐擦傷性の極めて高いラダー型シリコーン樹脂
が彼覆されるため、次工程の押出機７の二ノブルに接触
しても、光ファイバ裸線が損傷を受けることなく、強度
の高い光ファイバ心線が効率よく得られる。In the above-mentioned method for producing coated optical fiber, since the ladder-type silicone resin with extremely high scratch resistance is covered over the bare optical fiber, even if it comes into contact with the second knob of the extruder 7 in the next step, the optical fiber A strong optical fiber core can be efficiently obtained without damaging the bare wire.
また、ラダー型シリコーン樹脂が耐擦傷性に富んでいる
ので、この一次被覆の厚さを薄くしてもニップルによる
傷の発生がな《、通常２〜４μｍ程度の被覆厚さで、十
分この上に二次被覆を押出被覆することができ、細径化
が可能となる。また、被覆厚さを薄くできるので、架橋
（硬化）時間を短縮化でき、また架橋筒５の長さも短縮
化できることになって、第１図に示すように溶融紡糸か
ら二次被覆の押出被覆までを連続化（タンデム化）が可
能となり製造効率を高めることができる。In addition, since the ladder-type silicone resin has high scratch resistance, even if the thickness of this primary coating is made thinner, there will be no scratches caused by nipples. A secondary coating can be applied by extrusion to make the diameter smaller. In addition, since the coating thickness can be reduced, the crosslinking (curing) time can be shortened, and the length of the crosslinking tube 5 can also be shortened. As shown in FIG. This makes it possible to continuously (tandemize) up to 100 parts, increasing manufacturing efficiency.
さらに、上記ラダー型シリコーン樹脂は、優れた撥水性
、耐熱性（分解開始温度２５０゜Ｃ以上）を看するため
、例えば透湿性の高い熱可塑性樹脂であっても、他に優
れた特性を有すれば、その特性を活用出来る等、二次破
覆として使用される熱可塑性樹脂の選択範囲を大幅に広
げることが出来る。Furthermore, the ladder-type silicone resin has excellent water repellency and heat resistance (decomposition start temperature of 250°C or higher), so even if it is a thermoplastic resin with high moisture permeability, it may not have other excellent properties. By doing so, the selection range of thermoplastic resins used as secondary breakage can be greatly expanded, such as by making use of its properties.
また、上記ラダー型シリコーン樹脂被覆の厚さは数μｍ
で充分であるので、光ファイバ裸線の外径をほとんど変
えることがな《、寸法的｛こは光ファイバ裸線に直接熱
可塑性樹脂を被覆したものと同等と見做すことができる
。In addition, the thickness of the ladder type silicone resin coating is several μm.
Since this is sufficient, the outer diameter of the bare optical fiber is hardly changed (dimensionally, it can be considered to be equivalent to a bare optical fiber directly coated with a thermoplastic resin).
以上述べたように、本発明の光ファイバ心線の製造方去
は、一次被覆に耐擦傷性、耐熱性、撥水性を有するラダ
ー型シリコーン樹脂を用いているため、この一次破覆の
厚さを十分薄くしても押出機により熱可塑性樹脂を披覆
する際、二ノプルと接触しても損傷して強度が低するこ
とがなく、細径の心線を得ることができる。また、紡糸
から熱可塑性樹脂被覆までをタンデム化することができ
、連続して光ファイバ心線を効率よ《つ《ることかでき
る。さらに、透湿性の熱可塑性樹脂も使用出来る等、熱
可塑性樹脂の選択範囲が広がり、その特性を発揮させる
ことにより従来にない特性の光ファイバ心線が得られる
等、優れた光ファイバ心線が効率よく、安価に製造出来
る方法である。As described above, the manufacturing method of the optical fiber core of the present invention uses a ladder-type silicone resin having scratch resistance, heat resistance, and water repellency for the primary coating, so that the thickness of the primary coating is Even if it is made sufficiently thin, it will not be damaged and its strength will not decrease even if it comes into contact with the two nozzles when it is coated with thermoplastic resin using an extruder, and a core wire with a small diameter can be obtained. Furthermore, the processes from spinning to thermoplastic resin coating can be performed in tandem, and optical fiber cores can be produced continuously and efficiently. Furthermore, the selection range of thermoplastic resins has expanded, such as the ability to use moisture-permeable thermoplastic resins, and by leveraging the properties of these resins, it is possible to obtain optical fiber cores with unprecedented characteristics, resulting in excellent optical fiber cores. This is an efficient and inexpensive manufacturing method.
第１図は本発明の方法を実施する装置の一例を示す概略
図、第２図（ａ）（ｂ）（ｃ）はそれぞれ上記装置によ
ってつくられる光ファイバ裸線、素線、心線の晴断面図
である。
■・・・・・・先ファイバ裸線の母材（母材）、紡糸炉
、３・・・・・光ファイバ裸１ｉＩ＜裸線）、ラダー型
シリコーン樹脂コーティングポット、
４ａ・・・・・・ラダー型シリコーン、５・・・・・・
架橋筒、６・・・・・・先ファイバ素線（素線）、７・
・・・・・熱可塑性樹脂押出機、
８・・・・・・冷却筒、９・・・・・・光ファイバ心線
。FIG. 1 is a schematic diagram showing an example of an apparatus for carrying out the method of the present invention, and FIGS. 2(a), (b), and (c) are views of bare, stranded, and cored optical fibers produced by the above-mentioned apparatus, respectively. FIG. ■・・・Base material (base material) for bare end fiber, spinning furnace, 3... Bare optical fiber 1iI<bare wire), ladder type silicone resin coating pot, 4a...・Ladder type silicone, 5...
Bridging cylinder, 6...Fiber end wire (strand), 7.
... Thermoplastic resin extruder, 8 ... Cooling cylinder, 9 ... Optical fiber core wire.
Claims (1)
脂からなる被覆を設けたのち、引き続いて熱可塑性樹脂
の押出しによる被覆を行うことを特徴とする光ファイバ
心線の製造方法。1. A method for manufacturing an optical fiber core, which comprises providing a coating made of a ladder-type silicone resin to a melt-spun bare optical fiber, and then subsequently coating the coating by extruding a thermoplastic resin.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1054091A JPH02233537A (en) | 1989-03-07 | 1989-03-07 | Production of optical fiber core |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1054091A JPH02233537A (en) | 1989-03-07 | 1989-03-07 | Production of optical fiber core |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02233537A true JPH02233537A (en) | 1990-09-17 |
Family
ID=12960949
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1054091A Pending JPH02233537A (en) | 1989-03-07 | 1989-03-07 | Production of optical fiber core |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02233537A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011523397A (en) * | 2008-05-29 | 2011-08-11 | コーニング インコーポレイテッド | System and method for producing an optical fiber with a thermoplastic coating |
| US9725561B2 (en) | 2014-06-20 | 2017-08-08 | 3M Innovative Properties Company | Curable polymers comprising silsesquioxane polymer core and silsesquioxane polymer outer layer and methods |
| US9957358B2 (en) | 2014-09-22 | 2018-05-01 | 3M Innovative Properties Company | Curable polymers comprising silsesquioxane polymer core silsesquioxane polymer outer layer, and reactive groups |
| US9957416B2 (en) | 2014-09-22 | 2018-05-01 | 3M Innovative Properties Company | Curable end-capped silsesquioxane polymer comprising reactive groups |
| US10066123B2 (en) | 2013-12-09 | 2018-09-04 | 3M Innovative Properties Company | Curable silsesquioxane polymers, compositions, articles, and methods |
| US10370564B2 (en) | 2014-06-20 | 2019-08-06 | 3M Innovative Properties Company | Adhesive compositions comprising a silsesquioxane polymer crosslinker, articles and methods |
| US10392538B2 (en) | 2014-06-20 | 2019-08-27 | 3M Innovative Properties Company | Adhesive compositions comprising a silsesquioxane polymer crosslinker, articles and methods |
-
1989
- 1989-03-07 JP JP1054091A patent/JPH02233537A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011523397A (en) * | 2008-05-29 | 2011-08-11 | コーニング インコーポレイテッド | System and method for producing an optical fiber with a thermoplastic coating |
| US10066123B2 (en) | 2013-12-09 | 2018-09-04 | 3M Innovative Properties Company | Curable silsesquioxane polymers, compositions, articles, and methods |
| US9725561B2 (en) | 2014-06-20 | 2017-08-08 | 3M Innovative Properties Company | Curable polymers comprising silsesquioxane polymer core and silsesquioxane polymer outer layer and methods |
| US10370564B2 (en) | 2014-06-20 | 2019-08-06 | 3M Innovative Properties Company | Adhesive compositions comprising a silsesquioxane polymer crosslinker, articles and methods |
| US10392538B2 (en) | 2014-06-20 | 2019-08-27 | 3M Innovative Properties Company | Adhesive compositions comprising a silsesquioxane polymer crosslinker, articles and methods |
| US9957358B2 (en) | 2014-09-22 | 2018-05-01 | 3M Innovative Properties Company | Curable polymers comprising silsesquioxane polymer core silsesquioxane polymer outer layer, and reactive groups |
| US9957416B2 (en) | 2014-09-22 | 2018-05-01 | 3M Innovative Properties Company | Curable end-capped silsesquioxane polymer comprising reactive groups |
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