JPH04144944A - Glass fiber for light transmission - Google Patents
Glass fiber for light transmissionInfo
- Publication number
- JPH04144944A JPH04144944A JP2265849A JP26584990A JPH04144944A JP H04144944 A JPH04144944 A JP H04144944A JP 2265849 A JP2265849 A JP 2265849A JP 26584990 A JP26584990 A JP 26584990A JP H04144944 A JPH04144944 A JP H04144944A
- Authority
- JP
- Japan
- Prior art keywords
- glass fiber
- coating
- light transmission
- polycarbosilane
- fiber
- 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
- 239000003365 glass fiber Substances 0.000 title claims abstract description 26
- 230000005540 biological transmission Effects 0.000 title claims abstract description 16
- 239000000919 ceramic Substances 0.000 claims abstract description 13
- 229920003257 polycarbosilane Polymers 0.000 claims abstract description 12
- 229910018540 Si C Inorganic materials 0.000 claims abstract description 8
- 229910010271 silicon carbide Inorganic materials 0.000 claims abstract description 8
- 229920005989 resin Polymers 0.000 claims abstract description 6
- 239000011347 resin Substances 0.000 claims abstract description 6
- 230000003287 optical effect Effects 0.000 claims description 9
- 238000010304 firing Methods 0.000 claims description 4
- 239000011247 coating layer Substances 0.000 claims description 3
- 238000000576 coating method Methods 0.000 abstract description 26
- 239000011248 coating agent Substances 0.000 abstract description 25
- 239000002904 solvent Substances 0.000 abstract description 12
- 239000000835 fiber Substances 0.000 abstract description 6
- 238000009835 boiling Methods 0.000 abstract description 5
- 238000005253 cladding Methods 0.000 abstract description 4
- 239000010408 film Substances 0.000 description 11
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 6
- 239000013307 optical fiber Substances 0.000 description 6
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229920001721 polyimide Polymers 0.000 description 4
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- 239000004642 Polyimide Substances 0.000 description 3
- 229920000515 polycarbonate Polymers 0.000 description 3
- 239000004417 polycarbonate Substances 0.000 description 3
- 239000002243 precursor Substances 0.000 description 3
- 239000011261 inert gas Substances 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000012046 mixed solvent Substances 0.000 description 2
- 238000005240 physical vapour deposition Methods 0.000 description 2
- 229920000555 poly(dimethylsilanediyl) polymer Polymers 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 238000005491 wire drawing Methods 0.000 description 2
- QMMFVYPAHWMCMS-UHFFFAOYSA-N Dimethyl sulfide Chemical compound CSC QMMFVYPAHWMCMS-UHFFFAOYSA-N 0.000 description 1
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical compound CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 1
- 230000002378 acidificating effect Effects 0.000 description 1
- 239000005456 alcohol based solvent Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 239000003849 aromatic solvent Substances 0.000 description 1
- 125000003118 aryl group Chemical group 0.000 description 1
- 238000009412 basement excavation Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910010293 ceramic material Inorganic materials 0.000 description 1
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000006298 dechlorination reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 208000014674 injury Diseases 0.000 description 1
- 229910010272 inorganic material Inorganic materials 0.000 description 1
- 239000011147 inorganic material Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 239000009719 polyimide resin Substances 0.000 description 1
- 238000006462 rearrangement reaction Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 229920005992 thermoplastic resin Polymers 0.000 description 1
- 229920001187 thermosetting polymer Polymers 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
- 230000008733 trauma Effects 0.000 description 1
- -1 ultraviolet curable Polymers 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
- 239000008096 xylene Substances 0.000 description 1
Landscapes
- Optical Fibers, Optical Fiber Cores, And Optical Fiber Bundles (AREA)
- Surface Treatment Of Glass Fibres Or Filaments (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、外周に被覆を有する光伝送用ガラスファイバ
に関し、特に耐熱性にすぐれ、高温で使用可能な光伝送
用ガラスファイバに関するものである。Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a glass fiber for optical transmission having a coating on its outer periphery, and particularly to a glass fiber for optical transmission that has excellent heat resistance and can be used at high temperatures. .
（従来の技術）
従来、ガラスファイバは、ガラス単体では外傷により容
易に破断するために、その外周に熱硬化性、紫外線硬化
性、あるいは、熱可塑性の樹脂を被覆して、保護された
ガラスファイバを形成し、光伝送路体等に使用されてい
る。(Prior Art) Conventionally, glass fibers are easily broken by external trauma, so glass fibers have been protected by coating the outer periphery with thermosetting, ultraviolet curable, or thermoplastic resin. It is used for optical transmission line bodies, etc.
特に近年、特殊環境下での光ファイバの適用が望まれて
おり、油井発掘、機器、電力−光複合ケーブル、人工衛
星内ケーブル等高熱エネルギー、あるいは放射エネルギ
ーに曝される環境下で使用可能な耐熱性光ファイバの要
求が大きくなっている。Especially in recent years, optical fibers have been desired to be applied in special environments, and can be used in environments exposed to high heat energy or radiant energy, such as oil well excavations, equipment, power-optical composite cables, and satellite cables. There is a growing demand for heat-resistant optical fibers.
また、光伝送用以外にもガスクロマトグラフィに用いる
キャピラリカム等のガラスファイバにも耐熱性被覆の要
求が大きい。Furthermore, there is a strong demand for heat-resistant coatings not only for optical transmission but also for glass fibers such as capillary cams used for gas chromatography.
このような耐熱性被覆材としては、従来ポリイミドが用
いられていた。Polyimide has conventionally been used as such a heat-resistant coating material.
（発明が解決しようとする課題）
ポリイミドは他の樹脂に比べて耐熱性に秀れているが４
００℃以上では分解してしまう。(Problem to be solved by the invention) Polyimide has excellent heat resistance compared to other resins, but 4
It decomposes at temperatures above 00°C.
また、ラダー状ポリオルガノシロキサンも耐熱被覆材と
して検討されているが（特開昭５３−８８０９９号公報
） 、 ４００℃近傍て側鎖の分解がおこり、これ以上
の温度では塗膜として十分な特性を保つことができない
。Ladder-shaped polyorganosiloxane is also being considered as a heat-resistant coating material (Japanese Patent Laid-Open No. 53-88099), but its side chains decompose at around 400°C, and at temperatures above this it does not have sufficient properties as a coating film. can't keep it.
このような高温下で皮膜特性を保つためには有機高分子
材料ではもはや無理であり、セラミクス等の無機材料を
考える必要がある。金属やセラミクスて十分に緻密なコ
ーテイング膜を形成するためには、通常化学蒸着法（Ｃ
ＶＤ ）や物理蒸着法（ＰＶＤ）が用いられる。It is no longer possible to maintain film properties under such high temperatures using organic polymeric materials, and it is necessary to consider inorganic materials such as ceramics. In order to form sufficiently dense coating films on metals and ceramics, chemical vapor deposition (C
VD) and physical vapor deposition (PVD) are used.
しかし、これらの方法では成膜速度が遅いので紡糸直後
のガラスファイバ上に同時に塗布しようとすると、膜厚
０．１μｍ以下といったごくうすい皮膜しかできない。However, in these methods, the film formation speed is slow, so if an attempt is made to simultaneously coat the glass fibers immediately after spinning, only a very thin film with a thickness of 0.1 μm or less can be produced.
従って、このままでは十分な保護強度を保持することが
できない。Therefore, sufficient protection strength cannot be maintained as is.
（！１題を解決するための手段）
本発明者らは、上記の問題点を解決するためにポリカル
ボシランを主成分とする樹脂を前駆体とするＳｉ−Ｃ系
セラミクスを被覆として有するガラスファイバが４００
℃〜１０００℃といった高温ても使用可能であり、被覆
として十分な機械強度を示すことを見い出した。(Means for Solving !1 Problem) In order to solve the above problems, the present inventors have developed a glass coated with Si-C ceramics whose precursor is a resin containing polycarbosilane as a main component. 400 fibers
It has been found that it can be used even at high temperatures of 1000°C to 1000°C and exhibits sufficient mechanical strength as a coating.
ポリカルボンランを溶剤にとかすことにより適度の粘度
に調整することができ、第２図に示す如く、従来の装置
と同等の装置を用いて［直後のガラスファイバの表面に
ダイス等により塗布することができる。Polycarbonate can be adjusted to an appropriate viscosity by dissolving it in a solvent, and as shown in Figure 2, it can be applied directly onto the surface of the glass fiber using a die, etc., using a device equivalent to the conventional device. I can do it.
このファイバを焼付炉中を通し、溶剤を飛ばし、ポリカ
ルボシランの塗膜が形成される。The fiber is passed through a baking oven to remove the solvent and form a coating of polycarbosilane.
さらに、このファイバを１５０℃〜１５００℃の高温下
に３０分〜１０時間焼成することにより、ポリカルボシ
ランがＳｉ−Ｃ系セラミクスとなり耐熱性にすぐれ、か
つ厚い皮膜の形成されることを見い出し、本発明を完成
することができた。Furthermore, they discovered that by firing this fiber at a high temperature of 150°C to 1500°C for 30 minutes to 10 hours, the polycarbosilane turns into Si-C ceramics, which has excellent heat resistance and forms a thick film. We were able to complete the present invention.
集的には（ＣＨ３）２Ｓ＋Ｃｔ２ からＮａを用いて脱
塩素反応によりポリジメチルシランを得、ポリジメチル
シランの熱分解転位反応により合成することができる。Collectively, polydimethylsilane can be obtained from (CH3)2S+Ct2 by dechlorination reaction using Na, and synthesized by thermal decomposition rearrangement reaction of polydimethylsilane.
これを溶剤にとかすことにより線引工程でダイス等を用
いて塗布するのに最適な粘度に調整することが可能であ
る。By dissolving this in a solvent, it is possible to adjust the viscosity to the optimum level for coating using a die or the like in the wire drawing process.
溶剤としてはポリカルボシランと相溶性が良いもの、適
当な沸点をもつものである必要がある。硬化時に溶剤を
十分種数させるためには、沸点が低い方が好ましい。し
かしながら沸点が低すぎると、線引作業中に常温で溶剤
が揮散して粘度が高くなってしまうこと、硬化時に急激
に溶剤が揮散し、皮膜層中に気泡が発生するという問題
がある。The solvent must be compatible with polycarbosilane and have an appropriate boiling point. In order to use a sufficient number of solvents during curing, it is preferable that the boiling point is low. However, if the boiling point is too low, there are problems in that the solvent volatilizes at room temperature during wire drawing and the viscosity becomes high, and that the solvent volatilizes rapidly during curing and bubbles are generated in the film layer.
したがって、１００〜２５０℃の沸点を有するものが好
ましい。これに適合する溶剤としては、アルコール系、
芳香族系、エステル系等種々の溶剤が考えられるが、ポ
リカルボンランとの相溶性を考えるとエタノール、ｎ−
ブタノール等のアルコール系、トルエン、キンレン等の
芳香族系およびこれらの混合溶媒が特に好適である。Therefore, those having a boiling point of 100 to 250°C are preferred. Compatible solvents include alcohol,
Various solvents can be used, such as aromatic and ester, but considering their compatibility with polycarbonane, ethanol, n-
Particularly suitable are alcohol-based solvents such as butanol, aromatic solvents such as toluene and quinolene, and mixed solvents thereof.
このようにして粘度を調整することによって、第２図に
示したような線引装置を用い、線引直後のガラスファイ
バの外周にダイスを通して塗布し、焼付炉を通して溶剤
を揮散させ塗膜を形成することができる。By adjusting the viscosity in this way, the coating is applied to the outer circumference of the glass fiber immediately after drawing using a die as shown in Figure 2, and the solvent is volatilized through a baking oven to form a coating film. can do.
さらに、このポリカルボンランの塗膜は空気中、あるい
は不活性ガス雰囲気下で焼成することにより耐熱性が向
上するほか、ヤング率、引張り強度密度が高くなりセラ
ミクス化する。Furthermore, when this polycarbonate coating film is fired in air or in an inert gas atmosphere, its heat resistance is improved, and its Young's modulus and tensile strength density are increased, making it a ceramic material.
このようにして耐熱性にすぐれたＳｉ−Ｃセラミクス皮
膜が形成される。In this way, a Si-C ceramic film with excellent heat resistance is formed.
（作 用）
本発明のガラスファイバはポリカルボシランを前駆体と
するＳｉ−Ｃ系セラミクスを被覆として有しているので
耐熱性にすぐれ４００℃〜１０００℃といった高温でで
も使用することができる。(Function) Since the glass fiber of the present invention is coated with Si-C ceramics using polycarbosilane as a precursor, it has excellent heat resistance and can be used even at high temperatures of 400°C to 1000°C.
ＣＨ３ かすことにより適当な粘度に調整することができる。CH3 The viscosity can be adjusted to an appropriate level by rinsing.
この溶液をダイス等により線引直後のガラスファイバに
塗布し、焼付炉を通して溶剤をとばすことによりポリカ
ルボシランの塗膜が形成される。This solution is applied to the glass fiber immediately after drawing using a die or the like, and the solvent is blown off through a baking furnace to form a polycarbosilane coating.
このポリカルボシランは熱処理することにより、セラミ
クス化し耐熱性が付与されていく。When this polycarbosilane is heat-treated, it becomes a ceramic and is given heat resistance.
焼成温度は不活性ガス中で１５０〜１５００℃の温度で
処理される。焼成温度が高ければ高いほど皮膜はかたく
、引張り強度、耐熱性は高くなるが、あまり焼きすぎる
と伸びが小さく十分な可撓性が得られなくなる。The firing temperature is 150 to 1500°C in an inert gas. The higher the firing temperature, the harder the film will be, and the higher its tensile strength and heat resistance will be, but if it is fired too much, the elongation will be small and sufficient flexibility will not be obtained.
このようにして得られた被覆は良好な耐熱性を示すほか
に、以下のような長所がある。In addition to exhibiting good heat resistance, the coating thus obtained has the following advantages:
■ 水分を通しにくいので水によるガラスファイバの強
度低下を防止でき、疲労特性にすぐれたガラスファイバ
が得られる。■ Since it is difficult for water to pass through, it prevents the strength of the glass fiber from decreasing due to water, resulting in a glass fiber with excellent fatigue properties.
■ 耐薬品性にすぐれている。酸性、アルカリ性溶液、
オイル等のかかるような環境下ても使用できる。■ Excellent chemical resistance. acidic, alkaline solutions,
Can be used even in environments exposed to oil, etc.
（実 施 例）
実施例１
ポリカルボシランをキシレン、トルエン、ｎ−ブタノー
ルの混合溶媒中にとかし、固形分７０チの樹脂溶液を得
た。(Examples) Example 1 Polycarbosilane was dissolved in a mixed solvent of xylene, toluene, and n-butanol to obtain a resin solution with a solid content of 70 cm.
この樹脂を線引直後のコア径ｌＯμｍφ、クラツド径１
２５μｍφのシングルモードの光伝送用ガラスファイバ
に塗布した後、赤外炉を通し、ポリカルボンランの塗膜
を形成し、被覆径１４０μｍφとした。Immediately after drawing this resin, the core diameter is lOμmφ, and the cladding diameter is 1
After coating a single mode optical transmission glass fiber with a diameter of 25 μm, it was passed through an infrared oven to form a coating film of polycarbonate to give a coating diameter of 140 μm.
この被覆ファイバを８００℃で３０分焼成し、被覆をセ
ラミクス化し、第１図に示したような被覆光ファイバｌ
ｂ長を得た。This coated fiber was fired at 800°C for 30 minutes to make the coating into ceramic, and the coated optical fiber as shown in Figure 1 was produced.
Obtained length b.
このようにして製造した光伝送用ガラスファイバの波長
１３μｍにおける伝送損失は０．３５ｄＢ／ｌａ引張強
度は６〜７に４と良好であった。The optical transmission glass fiber manufactured in this way had a transmission loss of 0.35 dB/la at a wavelength of 13 μm, and a tensile strength of 4 to 6 to 7, which was good.
この被覆光ファイバを６００℃の恒温槽中にＸ日間放置
した後の波長１３μｍにおける伝送損失の増加は、０，
０１ｄＢ／ｌｌｎ 以下であった。引張り強度も６〜
７．に４を保っていた。また外観の変化も見られなかっ
た。After this coated optical fiber was left in a thermostat at 600°C for X days, the increase in transmission loss at a wavelength of 13 μm was 0,
It was less than 01 dB/lln. Tensile strength is also 6~
7. It was kept at 4. Moreover, no change in appearance was observed.
比較例１
線引直後のコア径１０μｍφ、クラツド径１２５μｍφ
のシングルモードの光伝送用ガラスファイバの外周にポ
リイミド樹脂を塗布した後赤外炉を通し、ポリイミドの
被覆を形成し、被覆径１５０μｍ“の被覆光ファイバＩ
ｌａ長を得た。Comparative Example 1 Core diameter immediately after drawing: 10 μmφ, cladding diameter: 125 μmφ
After applying polyimide resin to the outer periphery of a single-mode optical transmission glass fiber, it is passed through an infrared furnace to form a polyimide coating, thereby producing a coated optical fiber I with a coating diameter of 150 μm.
The la length was obtained.
このようにして製造した光伝送用ガラスファイバの波長
１．３μｍにおける伝送損失は０．３５ｄＢ／１ｍ引張
強度は６〜７Ｋｆと良好であった。The transmission loss of the optical transmission glass fiber manufactured in this way at a wavelength of 1.3 μm was 0.35 dB/1 m, and the tensile strength was as good as 6 to 7 Kf.
この被覆光ファイバを６００℃の恒温槽中に１日放置し
たところ被覆が著しく損傷し、部分的に被覆が剥離し、
ファイバが破断しているところが見つかった。When this coated optical fiber was left in a constant temperature bath at 600°C for one day, the coating was significantly damaged and partially peeled off.
A broken fiber was found.
（発明の効果）
以上説明したように１本発明のガラスファイバは被覆層
にポリカルボシランを前駆体とするＳｉ−Ｃ系セラミク
スを用いるので、耐熱性にすぐれており４００℃〜１０
００℃の高温でも使用することができる。(Effects of the Invention) As explained above, the glass fiber of the present invention uses Si-C ceramics with polycarbosilane as a precursor for the coating layer, so it has excellent heat resistance from 400 to 10
It can be used even at temperatures as high as 00°C.
第１図は、本発明の被覆されたガラスファイバの断面図
、第２図は、その製造装置を示す。
ここで、１はコア、 ２はクラッド
３はセラミクス層 、４はプリフォーム母材、５は線
引炉、６は線径測定器、７は塗布装置、８は焼付炉、
９は巻取機、 １０は制御系、１１はガラスファイバ
である。
（＠
１名）FIG. 1 is a sectional view of a coated glass fiber of the present invention, and FIG. 2 shows an apparatus for manufacturing the same. Here, 1 is a core, 2 is a cladding 3 is a ceramic layer, 4 is a preform base material, 5 is a drawing furnace, 6 is a wire diameter measuring device, 7 is a coating device, 8 is a baking furnace,
9 is a winding machine, 10 is a control system, 11 is a glass fiber
It is. (@1 person)
Claims (1)
おいて、該被覆層がポリカルボシランを主成分とする樹
脂を焼成して形成されたＳｉ−Ｃ系セラミクスからなる
ことを特徴とする光伝送用ガラスファイバA glass fiber for optical transmission having a structure having a coating layer on the outer periphery, characterized in that the coating layer is made of Si-C ceramics formed by firing a resin whose main component is polycarbosilane. glass fiber
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2265849A JPH04144944A (en) | 1990-10-02 | 1990-10-02 | Glass fiber for light transmission |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2265849A JPH04144944A (en) | 1990-10-02 | 1990-10-02 | Glass fiber for light transmission |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04144944A true JPH04144944A (en) | 1992-05-19 |
Family
ID=17422928
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2265849A Pending JPH04144944A (en) | 1990-10-02 | 1990-10-02 | Glass fiber for light transmission |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04144944A (en) |
-
1990
- 1990-10-02 JP JP2265849A patent/JPH04144944A/en active Pending
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