JPH06166911A - Production of carbon fiber - Google Patents
Production of carbon fiberInfo
- Publication number
- JPH06166911A JPH06166911A JP34316592A JP34316592A JPH06166911A JP H06166911 A JPH06166911 A JP H06166911A JP 34316592 A JP34316592 A JP 34316592A JP 34316592 A JP34316592 A JP 34316592A JP H06166911 A JPH06166911 A JP H06166911A
- Authority
- JP
- Japan
- Prior art keywords
- gas
- fiber
- furnace
- heating element
- graphitizing
- 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
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、炭素繊維の製造方法、
特に予備炭化処理に続く黒鉛化処理に使用する不活性ガ
ス雰囲気を改良した炭素繊維の製造方法に関する。FIELD OF THE INVENTION The present invention relates to a method for producing carbon fiber,
In particular, the present invention relates to a method for producing a carbon fiber having an improved inert gas atmosphere used in the graphitization treatment subsequent to the pre-carbonization treatment.
【０００２】[0002]
【従来の技術】石油系ピッチ、石炭系ピッチ等の炭素質
ピッチから製造される炭素繊維は、現在最も多量に製造
されているレ−ヨン系やＰＡＮ系の炭素繊維に比較して
予備炭化収率が高く、弾性率等の物理的特性も優れてお
り、更に低コストにて製造し得るという利点を有してい
るために近年注目を浴びている。2. Description of the Related Art Carbon fibers produced from carbonaceous pitch such as petroleum-based pitch and coal-based pitch have a preliminary carbonization yield as compared with rayon-based and PAN-based carbon fibers which are currently produced in the largest amount. In recent years, it has attracted attention because it has a high modulus, is excellent in physical properties such as elastic modulus, and has the advantage that it can be manufactured at low cost.
【０００３】現在、炭素繊維は、（１）石油系ピッチ、
石炭系ピッチ等から炭素繊維に適したピッチを調製し、
該ピッチを加熱溶融して紡糸機にて紡糸し、得られたピ
ッチ繊維を収束して繊維束と為した後、（２）前記ピッ
チ繊維を不融化炉にて酸化性雰囲気下にて最高温度２５
０〜３５０℃までに加熱して不融化し、（３）得られた
不融化繊維を予備予備炭化炉で不活性ガス雰囲気中にて
最高温度４００〜１５００℃まで加熱して予備予備炭化
し、（４）予備炭化された繊維を更に黒鉛化炉にて不活
性ガス雰囲気下に３０００℃以下にまで加熱して黒鉛化
すること、により製造されている。At present, carbon fibers are (1) petroleum pitch,
Prepare pitch suitable for carbon fiber from coal pitch, etc.
After the pitch is heated and melted and spun by a spinning machine, the obtained pitch fibers are converged to form a fiber bundle, and (2) the pitch fibers are heated in an infusible furnace under an oxidizing atmosphere at a maximum temperature. 25
(3) The obtained infusible fiber is heated to a maximum temperature of 400 to 1500 ° C. in an inert gas atmosphere in a preliminary preliminary carbonization furnace to be preliminary pre-carbonized, (4) It is produced by further heating the pre-carbonized fiber to 3000 ° C. or lower in an inert gas atmosphere in a graphitizing furnace to graphitize it.
【０００４】従来、上記の不融化、予備炭化、更には黒
鉛化の工程は、繊維束とされたピッチ繊維をテンション
下で連続不融化し、連続予備炭化し、連続黒鉛化する方
法が用いられている。Conventionally, in the above-mentioned steps of infusibilization, pre-carbonization, and further graphitization, pitch fibers made into a fiber bundle are continuously infusibilized under tension, continuously pre-carbonized, and continuously graphitized. ing.
【０００５】[0005]
【発明が解決しようとする課題】ところで、上記の予備
炭化された繊維の黒鉛化は、大気の黒鉛化炉内への侵入
を防いで繊維の酸化を防止するために、炉内を不活性ガ
ス雰囲気にするのに、不活性ガスとしてアルゴンガスを
使用して行なわれている。通常、そのガス供給量は、黒
鉛化炉内の発熱体部（炉本体部）に対して多くされてい
る。In the graphitization of the above pre-carbonized fiber, in order to prevent the atmospheric air from entering the graphitizing furnace and to prevent the oxidation of the fiber, an inert gas inside the furnace is used. Argon gas is used as an inert gas to create the atmosphere. Usually, the gas supply amount is large with respect to the heating element part (furnace main body part) in the graphitization furnace.
【０００６】しかしながら、アルゴンガスは希ガスであ
ることから極めて高価であり、炭素繊維の製造コストが
少なからず増大するという大きな欠点があった。However, since argon gas is a rare gas, it is extremely expensive, and there is a major drawback that the production cost of carbon fiber increases not a little.
【０００７】これに対し、黒鉛化炉に不活性ガスとして
窒素ガスを用いれば上記の問題点を解決できるが、黒鉛
化処理時に高温の炉の発熱体部で毒性のシアン（ジシア
ンＣ2 Ｎ2 ）やシアン化水素（ＨＣＮ）などシアン類が
多量に発生し、そのシアン類を多量に含んだ排ガスが炉
外に排出されるので、排ガスの処理に手間がかかる上、
黒鉛化炉の運転の安全性にも問題があった。又黒鉛化処
理に２５００℃以上の温度を採用した場合には、発熱体
部に設置された黒鉛発熱体の炭素と炉内の窒素の反応が
著しくなるため、発熱体部の損傷が著しくなる欠点もあ
った。On the other hand, when nitrogen gas is used as an inert gas in the graphitization furnace, the above problems can be solved, but toxic cyanide (dicyan C 2 N 2 ) is generated in the heating element of the high temperature furnace during the graphitization treatment. ), Hydrogen cyanide (HCN), and the like, a large amount of cyanides is generated, and the exhaust gas containing a large amount of the cyanides is discharged to the outside of the furnace.
There was also a problem in the operational safety of the graphitization furnace. Also, when a temperature of 2500 ° C. or higher is adopted for the graphitization treatment, the reaction between the carbon of the graphite heating element installed in the heating element and the nitrogen in the furnace becomes significant, so that the heating element is significantly damaged. There was also.
【０００８】本発明の目的は、黒鉛化炉に不活性ガスと
して窒素ガス及びアルゴンガスを用い、シアン化水素等
のシアン類が発生してもその発生量を低減して炉外に低
濃度で排出し、且つ炉の発熱体部の損傷を防止すること
を可能とし、黒鉛化炉の運転を安全且つローコストで行
なって、黒鉛化された炭素繊維を得ることができるよう
にした炭素繊維の製造方法を提供することである。An object of the present invention is to use nitrogen gas and argon gas as an inert gas in a graphitization furnace so that even if cyanides such as hydrogen cyanide are generated, the amount of the generated cyanides is reduced and the gas is discharged outside the furnace at a low concentration. A method for producing a carbon fiber, which is capable of preventing damage to the heating element of the furnace, and is capable of operating the graphitization furnace safely and at low cost to obtain graphitized carbon fiber. Is to provide.
【０００９】[0009]
【課題を解決するための手段】上記目的は本発明に係る
炭素繊維の製造方法にて達成される。要約すれば本発明
は、有機前駆体繊維の繊維束を不融化し、予備炭化し、
黒鉛化することからなる炭素繊維の製造方法において、
前記予備炭化された繊維の黒鉛化に使用する黒鉛化炉内
を不活性ガス雰囲気とするガスとして、炉のガスカーテ
ンシール部で窒素ガスを用い、炉の発熱体部でアルゴン
ガスを用い、窒素ガスの供給量を多量としアルゴンガス
の供給量を少量とした供給割合で供給して、前記炉内を
不活性ガス雰囲気としながら前記予備炭化された繊維を
黒鉛化することを特徴とする炭素繊維の製造方法であ
る。The above object can be achieved by the method for producing carbon fiber according to the present invention. In summary, the present invention infuses, pre-carbonizes, a fiber bundle of organic precursor fibers,
In the method for producing a carbon fiber comprising graphitizing,
Nitrogen gas is used in the gas curtain seal part of the furnace and argon gas is used in the heating element part of the furnace as a gas for forming an inert gas atmosphere in the graphitization furnace used for graphitizing the pre-carbonized fiber. A carbon fiber, characterized in that the pre-carbonized fiber is graphitized while being supplied with a supply ratio of a large amount of gas and a small amount of argon gas, and an inert gas atmosphere in the furnace. Is a manufacturing method.
【００１０】[0010]
【実施例】図１は、本発明の炭素繊維の製造方法で使用
する黒鉛化炉の一実施例を示す構成図である。図１に示
すように、黒鉛化炉１は、基本的に、黒鉛発熱体２を設
置した発熱体部（炉本体部）１Ｃと、その両端の入口、
出口のガスカーテンシール部１Ａ、１Ｂとからなってい
る。入口、出口のシール部１Ａ、１Ｂには、予備炭化さ
れた繊維、つまり予備炭化繊維Ｆの入口１ａ、出口１ｂ
が設けられている。EXAMPLE FIG. 1 is a constitutional view showing an example of a graphitization furnace used in the method for producing carbon fibers of the present invention. As shown in FIG. 1, the graphitization furnace 1 basically has a heating element portion (furnace body portion) 1C in which a graphite heating element 2 is installed, and inlets at both ends thereof.
It consists of gas curtain seals 1A and 1B at the outlet. The inlet and outlet seal portions 1A and 1B have inlets 1a and outlets 1b for pre-carbonized fibers, that is, pre-carbonized fibers F.
Is provided.
【００１１】発熱体部１Ｃ内には、その炉壁に設けられ
たガス供給口３ｃから不活性ガスを供給して発熱体２で
加熱することにより、最高温度１５００〜３０００℃の
範囲内の所定の一定温度の高温の不活性ガス雰囲気が維
持されている。入口及び出口のシール部１Ａ及び１Ｂ内
には、その炉壁に設けられたガス供給口３ａ及び３ｂか
ら不活性ガスを供給してガスのカーテンが形成されてお
り、これにより炉１外から空気がシール部１Ａ及び１Ｂ
を通って発熱体部１Ｃ内に侵入するのを阻止するように
なっている。A predetermined temperature within the range of 1500 to 3000 ° C. is obtained by supplying an inert gas into the heating element portion 1C from a gas supply port 3c provided in the furnace wall and heating by the heating element 2. A high temperature inert gas atmosphere of a constant temperature is maintained. Inside the inlet and outlet seals 1A and 1B, a gas curtain is formed by supplying an inert gas from the gas supply ports 3a and 3b provided on the furnace wall, thereby forming a gas curtain from outside the furnace 1. Are seals 1A and 1B
It is designed so as to be prevented from penetrating into the heating element portion 1C through.
【００１２】予備炭化繊維Ｆは、ピッチ繊維を紡糸して
繊維束と為した後、ピッチ繊維を不融化し、次いで予備
炭化して得られたものである。The pre-carbonized fiber F is obtained by spinning the pitch fiber into a fiber bundle, infusibilizing the pitch fiber, and then pre-carbonizing the pitch fiber.
【００１３】上記の繊維束とされたピッチ繊維は不融化
炉内を通糸され、最高温度２５０〜３５０℃の酸化性ガ
ス雰囲気中で加熱して不融化される。The pitch fibers made into the above-mentioned fiber bundles are passed through the infusibilizing furnace and heated in an oxidizing gas atmosphere having a maximum temperature of 250 to 350 ° C. to be infusibilized.
【００１４】ピッチ繊維を不融化して得られた不融化繊
維は、次いで予備炭化炉へと送給され、窒素又はアルゴ
ン等の不活性ガス雰囲気中で最高温度４００〜１５００
℃に加熱して、予備炭化される。The infusibilized fiber obtained by infusibilizing the pitch fiber is then fed to a preliminary carbonization furnace, and the maximum temperature is 400 to 1500 in an inert gas atmosphere such as nitrogen or argon.
It is pre-carbonized by heating to ° C.
【００１５】以上のようにして得た予備炭化繊維Ｆは、
繊維束の状態で所定の速度で、図１の黒鉛化炉１内を通
糸される。繊維Ｆは入口１ａから黒鉛化炉１内に導入さ
れ、入口カーテンシール部１Ａから発熱体部１Ｃ内に入
って、そこを通過する間に不活性ガス雰囲気下で最高温
度１５００〜３０００℃の所定の一定温度に加熱されて
黒鉛化され、炭素繊維（黒鉛繊維）が得られる。炭素繊
維は、出口カーテンシール部１Ｂを経て出口１ｂから炉
１外に導出され、図示しないボビンに巻取られる。The pre-carbonized fiber F obtained as described above is
The fiber bundle is passed through the graphitization furnace 1 of FIG. 1 at a predetermined speed. The fiber F is introduced into the graphitization furnace 1 from the inlet 1a, enters the heating element portion 1C from the inlet curtain seal portion 1A, and passes a predetermined temperature of 1500 to 3000 ° C. under an inert gas atmosphere while passing therethrough. Is heated to a constant temperature and graphitized to obtain carbon fibers (graphite fibers). The carbon fiber is led out of the furnace 1 through the outlet 1b through the outlet curtain seal portion 1B and wound on a bobbin (not shown).
【００１６】上記の黒鉛化炉１には、従来、不活性ガス
としてアルゴンガスが多用されているが、ガスのコスト
の点で黒鉛化炉１の運転費が高くなる問題がある。Conventionally, argon gas is often used as the inert gas in the above graphitization furnace 1, but there is a problem in that the operating cost of the graphitization furnace 1 becomes high in terms of gas cost.
【００１７】これをなくすためには、炉１内に不活性ガ
スとして窒素ガスを用いればよいが、しかしながら、黒
鉛化処理時に窒素ガスを用いると、炉１内の窒素が発熱
体部１Ｃの黒鉛発熱体２の炭素及び繊維から出た炭化水
素、水素と反応して、発熱体部１Ｃで毒性のシアン（ジ
シアンＣ2 Ｎ2 ）やシアン化水素（ＨＣＮ）などシアン
類が多量に発生する。In order to eliminate this, nitrogen gas may be used as an inert gas in the furnace 1. However, when nitrogen gas is used during the graphitization process, the nitrogen in the furnace 1 is replaced by the graphite of the heating element 1C. By reacting with the carbon of the heating element 2 and hydrocarbons and hydrogen generated from the fibers, a large amount of cyanides such as toxic cyan (dicyan C 2 N 2 ) and hydrogen cyanide (HCN) is generated in the heating element portion 1C.
【００１８】そこで、本発明では、不活性ガスとして黒
鉛化炉１の入口、出口のガスカーテンシール部１Ａ及び
１Ｂに窒素ガスを用い、発熱体部１Ｃにアルゴンガスを
用い、これらの窒素ガス及びアルゴンガスの供給量の割
合を、窒素ガスを多量とし、アルゴンガスを少量とし
た。即ち、ガス供給口３ａ及び３ｂからの窒素ガスの供
給量Ｑａ及びＱｂの合計量を多量とし、ガス供給口３ｃ
からのアルゴンガスの供給量Ｑｃを少量とした。Therefore, in the present invention, nitrogen gas is used for the gas curtain seal portions 1A and 1B at the inlet and outlet of the graphitization furnace 1 as the inert gas, and argon gas is used for the heating element portion 1C. Regarding the ratio of the supply amount of argon gas, the amount of nitrogen gas was set to be large and the amount of argon gas was set to be small. That is, the total amount of nitrogen gas supply amounts Qa and Qb from the gas supply ports 3a and 3b is increased, and the gas supply port 3c is increased.
The supply amount Qc of the argon gas supplied from was set to a small amount.
【００１９】これによれば、炉１の発熱体部１Ｃにはア
ルゴンガスを供給しているので、入口、出口のガスカー
テンシール部１Ａ及び１Ｂに窒素ガスを供給していて
も、黒鉛化処理時の高温によるシアンやシアン化水素の
発生は著しく低減する。又発熱体部１Ｃにアルゴンガス
を供給していることから、２４００℃以上の黒鉛化温度
を採用しても、黒鉛発熱体２の炭素と炉１内の窒素の反
応により発熱体部１Ｃが著しく損傷することがない。According to this, since the argon gas is supplied to the heating element portion 1C of the furnace 1, even if nitrogen gas is supplied to the inlet and outlet gas curtain seal portions 1A and 1B, the graphitization treatment is performed. Generation of cyanide and hydrogen cyanide due to high temperature at that time is significantly reduced. Further, since argon gas is supplied to the heating element portion 1C, even if the graphitization temperature of 2400 ° C. or higher is adopted, the heating element portion 1C remarkably changes due to the reaction between the carbon of the graphite heating element 2 and the nitrogen in the furnace 1. No damage.
【００２０】上記の入口、出口のガスシール部１Ａ及び
１Ｂの窒素ガスの供給量（Ｑａ＋Ｑｂ）と発熱体部１Ｃ
のアルゴンガスの供給量Ｑｃとの割合は、（Ｑａ＋Ｑ
ｂ）／Ｑｃ＝１／１〜２０／１＝１〜２０とすることが
好ましい。Supply amount (Qa + Qb) of nitrogen gas to the above-mentioned inlet and outlet gas seal portions 1A and 1B and the heating element portion 1C.
The ratio with the argon gas supply amount Qc is (Qa + Q
It is preferable that b) / Qc = 1/1 to 20/1 = 1 to 20.
【００２１】ガスの供給割合（Ｑａ＋Ｑｂ）／Ｑｃが１
未満では、発熱体部１Ｃのアルゴンガスの供給量Ｑｃが
少なすぎ、シアン化水素などのシアン類の発生を十分に
低減することができない。供給割合（Ｑａ＋Ｑｂ）／Ｑ
ｃが２０を超えると、繊維に毛羽立ちを生じる上、供給
するガスのコストが高くなるので、好ましくなくなる。
より好ましくは、ガス供給割合（Ｑａ＋Ｑｂ）／Ｑｃ＝
２〜１０である。Gas supply ratio (Qa + Qb) / Qc is 1
If it is less than 1, the supply amount Qc of the argon gas to the heating element portion 1C is too small, and the generation of cyanides such as hydrogen cyanide cannot be sufficiently reduced. Supply ratio (Qa + Qb) / Q
When c exceeds 20, fuzz is generated on the fiber and the cost of the gas to be supplied is increased, which is not preferable.
More preferably, gas supply ratio (Qa + Qb) / Qc =
2 to 10.
【００２２】本発明では、以上のように、黒鉛化炉１の
入口、出口のガスカーテンシール部１Ａ、１Ｂ内に多量
の窒素ガスを供給し、発熱体部１Ｃ内に少量のアルゴン
ガスを供給して不活性ガス雰囲気としたので、発熱体部
１Ｃでシアン化水素などのシアン類の発生を多量に生じ
ることなく、且つ発熱体部１Ｃの損傷を大きく生じるこ
となく黒鉛化炉１の運転を行なって、予備炭化繊維Ｆを
黒鉛化して炭素繊維（黒鉛繊維）を得ることができる。
従って黒鉛化炉１外に排出される排ガス中のシアン類の
濃度を低下することができ、排ガスの処理の手間がかか
らなくなるばかりか、又黒鉛化炉１の運転に安全性が確
保される。勿論、窒素ガスを併用したことにより、運転
コストの大幅な低減という大きなメリットもある。In the present invention, as described above, a large amount of nitrogen gas is supplied into the gas curtain seal portions 1A and 1B at the inlet and outlet of the graphitization furnace 1, and a small amount of argon gas is supplied into the heating element portion 1C. Since the atmosphere is made to be an inert gas, the graphitization furnace 1 can be operated without generating a large amount of cyanides such as hydrogen cyanide in the heating element section 1C and without significantly damaging the heating element section 1C. The pre-carbonized fiber F can be graphitized to obtain carbon fiber (graphite fiber).
Therefore, the concentration of cyanides in the exhaust gas discharged to the outside of the graphitization furnace 1 can be reduced, which not only saves the trouble of treating the exhaust gas, but also ensures the safety of the operation of the graphitization furnace 1. . Of course, the combined use of nitrogen gas has a great merit of drastically reducing the operating cost.
【００２３】以上では、黒鉛化炉１の発熱体部１Ｃへの
アルゴンガスの供給口は、発熱体部１Ｃの炉壁に設けた
供給口３ｃの１箇所として説明したが、本発明はこれに
限られず、発熱体部１Ｃの炉壁に複数箇所のガス供給口
を設けてアルゴンガスを供給しても良い。In the above description, the supply port of the argon gas to the heating element portion 1C of the graphitization furnace 1 is described as one position of the supply port 3c provided on the furnace wall of the heating element portion 1C, but the present invention is not limited to this. The invention is not limited to this, and the furnace wall of the heating element portion 1C may be provided with a plurality of gas supply ports to supply the argon gas.
【００２４】又入口、出口のガスシール部１Ａ及び１Ｂ
についても同様で、窒素ガスの供給口はそれらの炉壁に
それぞれガス供給口３ａ、３ｂの１箇所としたが、複数
箇所にガス供給口を設けて窒素ガスを供給することがで
きる。例えば入口、出口のガスシール部１Ａ及び１Ｂに
おいて、ガス供給口をそれらの中央部に１箇所、入口１
ａ、出口１ｂに近い箇所に１箇所、発熱体部１Ｃに近い
方に１箇所、計３箇所ずつと言うように設けることがで
きる。Further, gas seal portions 1A and 1B at the inlet and the outlet
The same applies to the above, but the nitrogen gas supply ports are provided at the gas supply ports 3a and 3b, respectively, on the furnace walls, but the gas supply ports may be provided at a plurality of positions to supply the nitrogen gas. For example, in the gas seal portions 1A and 1B at the inlet and the outlet, one gas supply port is provided at the central portion of the gas supply ports and the inlet 1
a, one at a location near the outlet 1b, and one at a location near the heating element 1C, that is, three locations in total.
【００２５】又ピッチ系炭素繊維の製造を例に採って説
明したが、本発明は、ピッチ以外にも、ポリアクリロニ
トリル、レーヨンなど有機前駆体の繊維から出発して炭
素繊維を製造する場合にも適用することができる。Although the production of pitch-based carbon fibers has been described as an example, the present invention is applicable to production of carbon fibers starting from fibers of organic precursors such as polyacrylonitrile and rayon, in addition to pitch. Can be applied.
【００２６】本発明の実施例につき具体例を説明する。A specific example of the embodiment of the present invention will be described.
【００２７】実施例１ 接触分解タールを原料として、熱分解重縮合により得た
光学的異方性相９８％からなる炭素繊維用ピッチを、５
００孔の紡糸口金を有する溶融紡糸機に通して紡糸し
た。Example 1 A pitch for carbon fiber comprising 98% of an optically anisotropic phase obtained by thermal decomposition polycondensation using catalytically cracked tar as a raw material was used.
It was spun through a melt spinning machine with a 00 hole spinneret.
【００２８】紡糸した５００本のフィラメントは、エア
サッカーで略収束してオイルリングローラーに導き、糸
に対して約０．１重量％の割合で収束用油剤を供給し、
５００フィラメントからなるピッチ繊維の糸条を形成し
た。油剤としては２５℃における粘度が１３ｃｓｔのメ
チルフェニルポリシロキサンキサンを使用した。The 500 spun filaments were substantially converged by an air sucker and led to an oil ring roller, and a converging oil agent was supplied at a ratio of about 0.1% by weight to the yarn,
A pitch fiber yarn consisting of 500 filaments was formed. As the oil agent, methylphenylpolysiloxanexane having a viscosity of 13 cst at 25 ° C. was used.
【００２９】上記のピッチ繊維はノズル下部に設けた高
速で回転するボビンに巻取り、約５００ｍ／分の巻取り
速度で１０分間紡糸した。The above pitch fiber was wound on a bobbin rotating at a high speed provided at the lower part of the nozzle and spun at a winding speed of about 500 m / min for 10 minutes.
【００３０】次いでピッチ繊維束を巻いた前記のボビン
６個を解舒し、そしてオイルリングローラーを使用して
耐熱性油剤を付与しながら合糸して、３０００フィラメ
ントからなるピッチ繊維束を形成し、他のボビンに巻取
った。Then, the above 6 bobbins wound with the pitch fiber bundle are unwound, and the yarns are combined while applying a heat-resistant oil agent using an oil ring roller to form a pitch fiber bundle of 3000 filaments. , Wound on another bobbin.
【００３１】合糸時に油剤として２５℃で３０ｃｓｔの
メチルフェニルポリシロキサン（フェニル基３５モル
％）を使用した。付与量は糸に対して０．５％であっ
た。Methylphenylpolysiloxane (35 mol% of phenyl groups) having a viscosity of 30 cst at 25 ° C. was used as an oil agent at the time of forming a yarn. The applied amount was 0.5% based on the yarn.
【００３２】このようにして得たボビン巻きのピッチ繊
維束をボビンから解除しつつ、酸化性ガス雰囲気として
酸素／窒素＝６０／４０の富酸素雰囲気の、炉入口温度
１９０℃、最高温度３００℃の温度勾配を持った不融化
炉に連続的に線状で送給して、ピッチ繊維を不融化し
た。While releasing the bobbin-wound pitch fiber bundle thus obtained from the bobbin, the furnace inlet temperature is 190 ° C. and the maximum temperature is 300 ° C. in an oxygen-rich atmosphere of oxygen / nitrogen = 60/40 as an oxidizing gas atmosphere. The pitch fiber was made infusible by continuously feeding it linearly to the infusibilizing furnace having a temperature gradient of.
【００３３】不融化の時間は１８分であった。不融化の
際、ピッチ繊維は１フィラメント当たり０．００７ｇの
テンションがかけられた。The infusibilization time was 18 minutes. When infusibilized, the pitch fiber was tensioned at 0.007 g per filament.
【００３４】不融化により得られた不融化繊維は、連続
して予備炭化炉に導入して最高温度１０００℃で予備炭
化した。予備炭化炉は入口部より４００、５００、６０
０、７００、１０００℃へと階段状に上昇する態様にて
加熱保持され、且つ窒素ガスを供給して炉内を窒素ガス
雰囲気に維持された。予備炭化に要した時間は７分であ
った。The infusibilized fiber obtained by the infusibilization was continuously introduced into a pre-carbonization furnace and pre-carbonized at a maximum temperature of 1000.degree. The pre-carbonization furnace is 400, 500, 60 from the inlet.
It was heated and held in a mode in which the temperature was raised stepwise to 0, 700, and 1000 ° C., and nitrogen gas was supplied to maintain the inside of the furnace in a nitrogen gas atmosphere. The time required for pre-carbonization was 7 minutes.
【００３５】上記の予備炭化によって得られた予備炭化
繊維Ｆは、次いで図１の黒鉛化炉１に連続的に通糸し
て、窒素ガス雰囲気中で黒鉛化を行なった。黒鉛化炉１
の炉温は２８００℃で、処理時間は１２０秒であった。
黒鉛化時、１フィラメント当たり０．１ｇのテンション
を付与した。The pre-carbonized fiber F obtained by the above-mentioned pre-carbonization was then continuously passed through the graphitizing furnace 1 shown in FIG. 1 and graphitized in a nitrogen gas atmosphere. Graphitization furnace 1
The furnace temperature was 2800 ° C., and the processing time was 120 seconds.
At the time of graphitization, a tension of 0.1 g per filament was applied.
【００３６】黒鉛化炉１の発熱体部１Ｃ内には、ガス供
給口３ｃから０．５ｍ3 ／ｈｒのガス供給量（Ｑｃ）で
アルゴンガスを供給し、入口、出口のガスカーテンシー
ル部１Ａ、１Ｂ内には、それぞれガス供給口３ａ、３ｂ
から４．５ｍ3 ／ｈｒのガス供給量（Ｑａ、Ｑｂ）で窒
素ガスを供給した。Argon gas is supplied into the heating element portion 1C of the graphitization furnace 1 from the gas supply port 3c at a gas supply amount (Qc) of 0.5 m 3 / hr, and the gas curtain seal portion 1A at the inlet and the outlet. 1B has gas supply ports 3a and 3b, respectively.
The nitrogen gas was supplied at a gas supply amount (Qa, Qb) of 4.5 m 3 / hr.
【００３７】入口、出口のガスシール部１Ａ、１Ｂの窒
素ガス供給量Ｑａ、Ｑｂの合計が９ｍ3 ／ｈｒ、炉１へ
のガス供給量の総計が９．５ｍ3 ／ｈｒ、入口、出口の
ガスシール部１Ａ及び１Ｂの窒素ガス供給量（Ｑａ＋Ｑ
ｂ）と発熱体部１Ｃのアルゴンガス供給量Ｑｃとの割合
は、（Ｑａ＋Ｑｂ）／Ｑｃ＝９／０．５＝１８／１であ
った。The sum of the nitrogen gas supply rates Qa and Qb of the gas seal portions 1A and 1B at the inlet and the outlet is 9 m 3 / hr, and the total gas supply rate to the furnace 1 is 9.5 m 3 / hr. Nitrogen gas supply amount (Qa + Q) of the gas seal parts 1A and 1B
The ratio of b) to the argon gas supply amount Qc of the heating element 1C was (Qa + Qb) /Qc=9/0.5=18/1.
【００３８】その結果、黒鉛化炉１の発熱体部１Ｃで多
量のシアン、シアン化水素を発生することなく黒鉛化処
理でき、炉１から排出される排ガス中のシアン及びシア
ン化水素量をシアン化水素量として測定した濃度で、入
口ガスカーテンシール部１Ａの繊維入口１ａから排出さ
れる排ガスにつき７．１ｐｐｍ、出口ガスカーテンシー
ル部１Ｂの繊維出口１ｂから排出される排ガスにつき
６．５ｐｐｍにできた。As a result, the heating element 1C of the graphitization furnace 1 can be graphitized without generating a large amount of cyanide and hydrogen cyanide, and the amounts of cyanide and hydrogen cyanide in the exhaust gas discharged from the furnace 1 were measured as the amount of hydrogen cyanide. Regarding the concentration, the exhaust gas discharged from the fiber inlet 1a of the inlet gas curtain seal portion 1A was 7.1 ppm, and the exhaust gas discharged from the fiber outlet 1b of the outlet gas curtain seal portion 1B was 6.5 ppm.
【００３９】上記の測定は北川検知管法によって行なっ
た。The above measurement was carried out by the Kitagawa detector tube method.
【００４０】又上記の窒素ガス及びアルゴンガスによる
不活性ガス雰囲気下での黒鉛化を行なって得られた炭素
繊維（黒鉛繊維）は、その黒鉛化に何らの問題もなく、
繊維の引張強度は３６０ｋｇ／ｍｍ2 、引張弾性率は９
０ｔｏｎ／ｍｍ2 の物性を示した。The carbon fiber (graphite fiber) obtained by graphitizing the above-mentioned nitrogen gas and argon gas in an inert gas atmosphere has no problem in graphitization.
The tensile strength of the fiber is 360 kg / mm 2 , and the tensile elastic modulus is 9
The physical properties were 0 ton / mm 2 .
【００４１】実施例２ 黒鉛化時、図１の黒鉛化炉１の発熱体部１Ｃへのアルゴ
ンガス供給量Ｑｃを０．５ｍ3 ／ｈｒ、入口、出口のガ
スカーテンシール部１Ａ、１Ｂへの窒素ガスのガス供給
量Ｑａ、Ｑｂをそれぞれ１ｍ3 ／ｈｒとした以外は、実
施例１と同様に処理した。Example 2 During graphitization, the argon gas supply amount Qc to the heating element 1C of the graphitization furnace 1 of FIG. 1 was 0.5 m 3 / hr, and gas curtain seals 1A and 1B at the inlet and the outlet were supplied. The same process as in Example 1 was performed except that the gas supply amounts Qa and Qb of nitrogen gas were each set to 1 m 3 / hr.
【００４２】この場合、入口、出口のガスシール部１
Ａ、１Ｂの窒素ガス供給量Ｑａ、Ｑｂの合計は２ｍ3 ／
ｈｒ、炉１へのガス供給量の総計は２．５ｍ3 ／ｈｒで
あり、入口、出口のガスシール部１Ａ及び１Ｂの窒素ガ
ス供給量（Ｑａ＋Ｑｂ）と発熱体部１Ｃのアルゴンガス
供給量Ｑｃとの割合は、（Ｑａ＋Ｑｂ）／Ｑｃ＝２／
０．５＝４／１であった。In this case, the gas seal portion 1 at the inlet and the outlet
The total of the nitrogen gas supply amounts Qa and Qb of A and 1B is 2 m 3 /
hr, the total gas supply amount to the furnace 1 is 2.5 m 3 / hr, and the nitrogen gas supply amount (Qa + Qb) of the gas seal parts 1A and 1B at the inlet and the outlet and the argon gas supply amount Qc of the heating element part 1C. And the ratio is (Qa + Qb) / Qc = 2 /
It was 0.5 = 4/1.
【００４３】その結果、黒鉛化炉炉１から排出される排
ガスについて測定したシアン化水素の濃度（上記したよ
うにシアンを含む）は、入口ガスカーテンシール部１Ａ
の繊維入口１ａから排出される排ガスで１８ｐｐｍ、出
口ガスカーテンシール部１Ｂの繊維出口１ｂから排出さ
れる排ガスで１６ｐｐｍであった。As a result, the concentration of hydrogen cyanide (including cyan as described above) measured in the exhaust gas discharged from the graphitization furnace 1 is determined by the inlet gas curtain seal portion 1A.
The exhaust gas discharged from the fiber inlet 1a was 18 ppm, and the exhaust gas discharged from the fiber outlet 1b of the outlet gas curtain seal portion 1B was 16 ppm.
【００４４】又良好に黒鉛化された炭素繊維（黒鉛繊
維）が得られ、その黒鉛繊維の引張強度は３５５ｋｇ／
ｍｍ2 、引張弾性率は９０ｔｏｎ／ｍｍ2 の物性を示し
た。Further, a graphitized carbon fiber (graphite fiber) is obtained, and the tensile strength of the graphite fiber is 355 kg /
The physical properties of mm 2 and the tensile elastic modulus were 90 ton / mm 2 .
【００４５】[0045]
【発明の効果】以上説明したように、本発明の製造方法
では、黒鉛化炉の発熱体部に少量のアルゴンガスを供給
したので、炉の入口、出口のガスカーテンシール部に窒
素ガスを供給しても、発熱体部でシアン化水素などのシ
アン類が多量に発生するのを防止し、排ガス中のシアン
類の濃度を顕著に低減して黒鉛化炉を運転でき、炉の運
転を安全且つローコストで行なって予備炭化された繊維
を黒鉛化して、黒鉛化された炭素繊維を得ることができ
る。As described above, in the manufacturing method of the present invention, since a small amount of argon gas was supplied to the heating element of the graphitization furnace, nitrogen gas was supplied to the gas curtain seals at the furnace inlet and outlet. Even if a large amount of cyanide such as hydrogen cyanide is generated in the heating element, the graphitization furnace can be operated by significantly reducing the concentration of cyanide in the exhaust gas, and the operation of the furnace is safe and at low cost. The graphitized carbon fibers can be obtained by graphitizing the pre-carbonized fibers performed in step 1.
【図１】本発明の炭素繊維の製造方法で使用する黒鉛化
炉の一実施例を示す構成図である。FIG. 1 is a configuration diagram showing an example of a graphitization furnace used in the method for producing carbon fibers of the present invention.
１ 黒鉛化炉 １ａ 繊維入口 １ｂ 繊維出口 １Ａ 入口ガスカーテンシール部 １Ｂ 出口ガスカーテンシール部 １Ｃ 発熱体部 ２ 発熱体 ３ａ〜３ｃ ガス供給口 Ｆ 予備炭化された繊維 1 Graphitizing Furnace 1a Fiber Inlet 1b Fiber Outlet 1A Inlet Gas Curtain Seal Part 1B Outlet Gas Curtain Seal Part 1C Heating Element 2 Heating Elements 3a-3c Gas Supply Port F Pre-Carbonized Fiber
───────────────────────────────────────────────────── フロントページの続き (72)発明者 日野 隆 埼玉県入間郡大井町西鶴ケ岡１−３−１ 東燃株式会社総合研究所内 (72)発明者 山本 雅晴 埼玉県入間郡大井町西鶴ケ岡１−３−１ 東燃株式会社総合研究所内 ─────────────────────────────────────────────────── --- Continuation of front page (72) Inventor Takashi Hino 1-3-1 Nishitsurugaoka, Oi-cho, Iruma-gun, Saitama Tonen Co., Ltd. Research Institute (72) Masaharu Yamamoto Nishi-tsurugaoka, Oi-cho, Iruma-gun, Saitama Prefecture 1- 3-1 Inside Tonen Research Institute
Claims (1)
備炭化し、黒鉛化することからなる炭素繊維の製造方法
において、前記予備炭化された繊維の黒鉛化に使用する
黒鉛化炉内を不活性ガス雰囲気とするガスとして、炉の
ガスカーテンシール部で窒素ガスを用い、炉の発熱体部
でアルゴンガスを用い、窒素ガスの供給量を多量としア
ルゴンガスの供給量を少量とした供給割合で供給して、
前記炉内を不活性ガス雰囲気としながら前記予備炭化さ
れた繊維を黒鉛化することを特徴とする炭素繊維の製造
方法。1. A method for producing a carbon fiber comprising infusibilizing a fiber bundle of an organic precursor fiber, pre-carbonizing and graphitizing the carbon fiber in a graphitizing furnace used for graphitizing the pre-carbonized fiber. As an inert gas atmosphere, nitrogen gas is used in the gas curtain seal part of the furnace, argon gas is used in the heating element part of the furnace, the supply amount of nitrogen gas is made large and the supply amount of argon gas is made small. Supply at the supply rate,
A method for producing a carbon fiber, which comprises graphitizing the pre-carbonized fiber while maintaining an inert gas atmosphere in the furnace.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34316592A JPH06166911A (en) | 1992-11-30 | 1992-11-30 | Production of carbon fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34316592A JPH06166911A (en) | 1992-11-30 | 1992-11-30 | Production of carbon fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH06166911A true JPH06166911A (en) | 1994-06-14 |
Family
ID=18359419
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP34316592A Pending JPH06166911A (en) | 1992-11-30 | 1992-11-30 | Production of carbon fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH06166911A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102134628B1 (en) * | 2020-01-08 | 2020-07-16 | 재단법인 철원플라즈마 산업기술연구원 | Apparatus and method manufacturing carbon fiber |
-
1992
- 1992-11-30 JP JP34316592A patent/JPH06166911A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR102134628B1 (en) * | 2020-01-08 | 2020-07-16 | 재단법인 철원플라즈마 산업기술연구원 | Apparatus and method manufacturing carbon fiber |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3656904A (en) | Graphitization process | |
| JP2000345435A (en) | Pitch fiber bundle, pitch-based carbon fiber bundle and its production | |
| US4552743A (en) | Process for producing carbon fiber | |
| US4574077A (en) | Process for producing pitch based graphite fibers | |
| JPH06166911A (en) | Production of carbon fiber | |
| US3723605A (en) | Process for the production of a continuous length of graphitic fibrous material | |
| JPH06166913A (en) | Production of carbon fiber | |
| US4788050A (en) | Process for producing pitch-based carbon fibers | |
| JPS6021911A (en) | Manufacture of carbon fiber product | |
| JP2930166B2 (en) | Carbon fiber production method | |
| JPH0617319A (en) | Production of pitch-based carbon fiber | |
| JPH06146120A (en) | Pitch-based carbon fiber having high strength and high elastic modulus and its production | |
| JPH06184831A (en) | Production of carbon fiber | |
| JP2695355B2 (en) | Carbon fiber production method | |
| EP0068752B1 (en) | Calcium intercalated boronated carbon fibre | |
| JPS60126324A (en) | Method for producing carbon fiber bundle having high orientation of filament | |
| JPS61258020A (en) | Production of pitch based carbon fiber | |
| JP3577823B2 (en) | Manufacturing method of graphite fiber | |
| KR20030047072A (en) | A rayon-type twisted carbon fiber and a method of preparing same | |
| JPH04119124A (en) | Production of pitch-based carbon fiber and graphite fiber | |
| JP2023117438A (en) | Heat-treated flame-resistant fiber, heat-treated flame-resistant fiber sheet and method for producing the same, and method for producing graphite fiber and graphite fiber sheet | |
| JPH06166915A (en) | Guide bar in infusibilizing furnace thereof for producing pitch-based carbon fiber | |
| JPH05287617A (en) | Production of pitch carbon fiber | |
| JPH06146121A (en) | Production of carbon fiber | |
| JPH05171519A (en) | Production of pitch carbon fiber |