JPH04272234A - Production of pitch-base carbon fiber and graphite fiber - Google Patents
Production of pitch-base carbon fiber and graphite fiberInfo
- Publication number
- JPH04272234A JPH04272234A JP5931591A JP5931591A JPH04272234A JP H04272234 A JPH04272234 A JP H04272234A JP 5931591 A JP5931591 A JP 5931591A JP 5931591 A JP5931591 A JP 5931591A JP H04272234 A JPH04272234 A JP H04272234A
- Authority
- JP
- Japan
- Prior art keywords
- fiber bundle
- temperature
- pitch
- fiber
- stretching
- 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
- 239000000835 fiber Substances 0.000 title claims abstract description 213
- 229920000049 Carbon (fiber) Polymers 0.000 title claims abstract description 59
- 239000004917 carbon fiber Substances 0.000 title claims abstract description 59
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims description 15
- 229910002804 graphite Inorganic materials 0.000 title claims description 15
- 239000010439 graphite Substances 0.000 title claims description 15
- 238000004519 manufacturing process Methods 0.000 title claims description 13
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title abstract description 29
- 238000003763 carbonization Methods 0.000 claims abstract description 41
- 238000010000 carbonizing Methods 0.000 claims abstract description 4
- 239000012298 atmosphere Substances 0.000 claims description 28
- 238000011282 treatment Methods 0.000 claims description 28
- 238000002844 melting Methods 0.000 claims description 21
- 230000008018 melting Effects 0.000 claims description 21
- 230000001590 oxidative effect Effects 0.000 claims description 7
- 230000003028 elevating effect Effects 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 abstract description 54
- 238000000034 method Methods 0.000 abstract description 28
- 239000011295 pitch Substances 0.000 description 63
- 238000009656 pre-carbonization Methods 0.000 description 19
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 17
- 239000007789 gas Substances 0.000 description 17
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 16
- 239000000155 melt Substances 0.000 description 14
- 239000003921 oil Substances 0.000 description 14
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 13
- 239000003795 chemical substances by application Substances 0.000 description 13
- 239000001301 oxygen Substances 0.000 description 13
- 229910052760 oxygen Inorganic materials 0.000 description 13
- 229910001873 dinitrogen Inorganic materials 0.000 description 9
- 230000001965 increasing effect Effects 0.000 description 9
- 230000000704 physical effect Effects 0.000 description 9
- 229910052786 argon Inorganic materials 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 6
- 239000011261 inert gas Substances 0.000 description 5
- 239000003963 antioxidant agent Substances 0.000 description 4
- 239000002131 composite material Substances 0.000 description 4
- 229910052757 nitrogen Inorganic materials 0.000 description 4
- 238000004513 sizing Methods 0.000 description 4
- 239000004094 surface-active agent Substances 0.000 description 4
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 3
- 230000003078 antioxidant effect Effects 0.000 description 3
- 239000011300 coal pitch Substances 0.000 description 3
- 238000010304 firing Methods 0.000 description 3
- 239000011301 petroleum pitch Substances 0.000 description 3
- -1 polysiloxane Polymers 0.000 description 3
- 229920001296 polysiloxane Polymers 0.000 description 3
- 238000009987 spinning Methods 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 2
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- LRHPLDYGYMQRHN-UHFFFAOYSA-N N-Butanol Chemical compound CCCCO LRHPLDYGYMQRHN-UHFFFAOYSA-N 0.000 description 2
- 229920003171 Poly (ethylene oxide) Polymers 0.000 description 2
- 239000003570 air Substances 0.000 description 2
- 125000000217 alkyl group Chemical group 0.000 description 2
- 150000004945 aromatic hydrocarbons Chemical class 0.000 description 2
- 238000009835 boiling Methods 0.000 description 2
- 239000004205 dimethyl polysiloxane Substances 0.000 description 2
- 235000013870 dimethyl polysiloxane Nutrition 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 235000019441 ethanol Nutrition 0.000 description 2
- 239000000295 fuel oil Substances 0.000 description 2
- 239000012299 nitrogen atmosphere Substances 0.000 description 2
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 2
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 description 2
- 238000006068 polycondensation reaction Methods 0.000 description 2
- BDERNNFJNOPAEC-UHFFFAOYSA-N propan-1-ol Chemical compound CCCO BDERNNFJNOPAEC-UHFFFAOYSA-N 0.000 description 2
- 238000000197 pyrolysis Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- KUUNNVBBPBDFJZ-UHFFFAOYSA-N 1-dodecylselanyldodecane Chemical compound CCCCCCCCCCCC[Se]CCCCCCCCCCCC KUUNNVBBPBDFJZ-UHFFFAOYSA-N 0.000 description 1
- WJFKNYWRSNBZNX-UHFFFAOYSA-N 10H-phenothiazine Chemical compound C1=CC=C2NC3=CC=CC=C3SC2=C1 WJFKNYWRSNBZNX-UHFFFAOYSA-N 0.000 description 1
- XQVWYOYUZDUNRW-UHFFFAOYSA-N N-Phenyl-1-naphthylamine Chemical compound C=1C=CC2=CC=CC=C2C=1NC1=CC=CC=C1 XQVWYOYUZDUNRW-UHFFFAOYSA-N 0.000 description 1
- 239000005662 Paraffin oil Substances 0.000 description 1
- 239000002202 Polyethylene glycol Substances 0.000 description 1
- 229920000297 Rayon Polymers 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 125000005907 alkyl ester group Chemical group 0.000 description 1
- 150000005215 alkyl ethers Chemical class 0.000 description 1
- 150000001412 amines Chemical class 0.000 description 1
- 239000011337 anisotropic pitch Substances 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000004523 catalytic cracking Methods 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 239000003995 emulsifying agent Substances 0.000 description 1
- 230000001804 emulsifying effect Effects 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 238000005087 graphitization Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002074 melt spinning Methods 0.000 description 1
- 239000011302 mesophase pitch Substances 0.000 description 1
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 150000002989 phenols Chemical class 0.000 description 1
- 229950000688 phenothiazine Drugs 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920001223 polyethylene glycol Polymers 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000002964 rayon Substances 0.000 description 1
- 229940065287 selenium compound Drugs 0.000 description 1
- 150000003343 selenium compounds Chemical class 0.000 description 1
- 229920002545 silicone oil Polymers 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 238000005979 thermal decomposition reaction Methods 0.000 description 1
- 238000012719 thermal polymerization Methods 0.000 description 1
Landscapes
- Yarns And Mechanical Finishing Of Yarns Or Ropes (AREA)
- Inorganic Fibers (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は、一般には炭素繊維（本
明細書にて「炭素繊維」とは特に明記しない場合には炭
素繊維のみならず黒鉛繊維をも含めて使用する。）の製
造方法に関するものであり、特に種々の炭素質ピッチか
ら炭素繊維を極めて効率よく且つ多量に製造する方法に
関するものである。[Industrial Application Field] The present invention generally relates to the production of carbon fibers (in this specification, unless otherwise specified, "carbon fibers" is used to include not only carbon fibers but also graphite fibers). The present invention relates to a method for producing carbon fibers from various carbonaceous pitches in a highly efficient manner and in large quantities.
【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ピッチ系炭素繊維は、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。[Prior Art] Pitch-based carbon fibers manufactured from carbonaceous pitches such as petroleum-based pitch and coal-based pitch are more carbonized than rayon-based and PAN-based carbon fibers, which are currently produced in large quantities. It has attracted attention in recent years because it has the advantages of high yield, excellent physical properties such as elastic modulus, and can be manufactured at low cost.
【０００３】現在、ピッチ系炭素繊維は、（１）石油系
ピッチ、石炭系ピッチ等から炭素繊維に適した炭素質ピ
ッチを調製し、該炭素質ピッチを加熱溶融して紡糸機に
て紡糸し、集束してピッチ繊維束を製造し、（２）前記
ピッチ繊維束を不融化炉にて酸化性雰囲気下にて１５０
〜３５０℃までに加熱して不融化し、（３）次いで、不
融化された繊維束を炭化炉にて不活性雰囲気下にて３０
００℃以下にまで加熱して炭化或は黒鉛化すること、に
より製造されている。[0003]Currently, pitch-based carbon fibers are produced by (1) preparing carbonaceous pitch suitable for carbon fiber from petroleum-based pitch, coal-based pitch, etc., heating and melting the carbonaceous pitch, and spinning it with a spinning machine. (2) The pitch fiber bundle is heated in an infusible furnace under an oxidizing atmosphere for 150 min.
(3) Then, the infusible fiber bundle was heated to ~350°C in an inert atmosphere for 30 minutes.
It is manufactured by heating to below 00°C to carbonize or graphitize.
【０００４】しかしながら、従来の技術によっては、ピ
ッチ繊維、不融化繊維の引張強度が約０．０１ＧＰａと
小さい上、脆いためにその取扱いが難しく、高性能製品
を得るのに必要なロングフィラメント状の繊維を安定し
て多量に得ることが極めて困難であった。However, with conventional techniques, pitch fibers and infusible fibers have a low tensile strength of about 0.01 GPa and are brittle, making them difficult to handle. It has been extremely difficult to stably obtain fibers in large quantities.
【０００５】これらの問題解決方法の一つとして、本発
明者等は、炭素質ピッチを紡糸して得たピッチ繊維を合
糸してストレート系油剤を付与することによって繊維束
の強さを強くした上で、酸素濃度が３０％以上の富酸素
ガス中で、繊維束を連続的に線状で通して不融化する方
法を提案した（特開昭６３−２６４９１７号を参照せよ
）。[0005] As one method for solving these problems, the present inventors have strengthened the strength of the fiber bundle by doubling pitch fibers obtained by spinning carbonaceous pitch and applying a straight oil. Then, they proposed a method of infusible fiber bundles by passing them continuously in a line in an oxygen-rich gas having an oxygen concentration of 30% or more (see JP-A No. 63-264917).
【０００６】[0006]
【発明が解決しようとする課題】ところで、不融化繊維
束の予備炭化の工程で不融化繊維束を延伸できれば、こ
れを炭素繊維にしたときに、炭素繊維の引張強度、引張
弾性率及び圧縮強度を向上できる可能性があるが、通糸
する不融化繊維が約０．０１ＧＰａと脆弱であるために
、炭素繊維の引張強度、引張弾性率及び圧縮強度等の物
性を大きく改善させ得るほどに不融化繊維束を十分に延
伸処理することは難しく、不融化繊維束の十分な延伸処
理を無理に行なうと、却って炭素繊維の物性、特に引張
強度を下げる結果になってしまう。このため、従来、不
融化繊維束の延伸処理による炭素繊維の物性の改善によ
って、引張強度、引張弾性率及び圧縮強度を向上した炭
素繊維を得ることは困難であった。[Problem to be Solved by the Invention] By the way, if the infusible fiber bundle can be drawn in the process of preliminary carbonization of the infusible fiber bundle, when this is made into carbon fiber, the tensile strength, tensile modulus, and compressive strength of the carbon fiber can be improved. However, since the infusible fiber to be threaded is fragile at about 0.01 GPa, it is not sufficient to significantly improve the physical properties such as tensile strength, tensile modulus, and compressive strength of carbon fiber. It is difficult to sufficiently draw a fusible fiber bundle, and if the infusible fiber bundle is forcibly drawn sufficiently, the physical properties of the carbon fibers, especially the tensile strength, will be reduced. For this reason, conventionally, it has been difficult to obtain carbon fibers with improved tensile strength, tensile modulus, and compressive strength by improving the physical properties of carbon fibers by drawing an infusible fiber bundle.
【０００７】又不融化繊維束を、化学的に不活性なアル
ゴン又は窒素ガスなどの雰囲気中で５００〜１０００℃
まで昇温して初期の炭化を行なう予備炭化工程に、線状
で通した場合には特開昭５９−１５５１７号に開示され
るように、繊維の温度が７００〜８００℃の温度に達す
るまでに、繊維の強さが室温下の強さより大幅に減少し
、予備炭化処理中に炉内で繊維が切断し、毛羽立ち易い
という大きな欠点があった。[0007] The infusible fiber bundle is heated at 500 to 1000°C in a chemically inert atmosphere such as argon or nitrogen gas.
When the fibers are passed through a preliminary carbonization step in which the temperature is raised to 700 to 800°C, as disclosed in JP-A-59-15517, Another major disadvantage was that the strength of the fibers was significantly reduced compared to the strength at room temperature, and the fibers were easily cut in the furnace during the preliminary carbonization process, causing them to become fluffy.
【０００８】上記特開昭６３−２６４９１７号に記載の
発明も、この問題点を根本的に解決し得るものではなく
、予備炭化炉において不融化繊維の炉内断糸が頻繁に発
生し、通糸歩留りが低下し、毛羽立ち易いという問題が
あった。The invention described in JP-A No. 63-264917 cannot fundamentally solve this problem, and breaks of the infusible fibers frequently occur in the pre-carbonization furnace. There were problems in that the yarn yield was low and the yarn was easily fluffed.
【０００９】更に、１本の不融化繊維束は、１００〜１
０００００本のフィラメントが集束されて構成された繊
維束の形態とされており、従って、予備炭化に際して、
各フィラメントが融着したり、膠着したりする度合いが
大となり、製品である焼成処理後の炭素繊維の品質に問
題を生じるという大きな欠点が発生した。Furthermore, one infusible fiber bundle has 100 to 1
It is in the form of a fiber bundle composed of 00,000 filaments, and therefore, during preliminary carbonization,
A major drawback occurred in that each filament was fused or stuck to a large degree, causing a problem in the quality of the carbon fiber product after firing treatment.
【００１０】本発明者等は、連続焼成プロセスにおいて
炭素繊維を製造する方法を研究する過程で、繊維束の延
伸処理を、ピッチ繊維束の不融化、不融化繊維束の予備
炭化及び予備炭化繊維束の炭化の段階に分割して、ピッ
チ繊維束の不融化を、酸化性ガス雰囲気中で繊維束の溶
融破断温度よりも３０〜１００℃低い温度まで急速に昇
温して、繊維束を極く短時間で熱処理しながら同時に延
伸処理することにより行ない、且つ不融化繊維束の予備
炭化を、不活性ガス雰囲気中で繊維束の溶融破断温度よ
りも３０〜１００℃低い温度まで同様に急速に昇温して
、繊維束を極く短時間で熱処理しながら同時に延伸処理
することにより行ない、更に予備炭化繊維束の炭化を、
繊維束に延伸処理を加えながら行なえば、従来のように
、不融化繊維束の予備炭化の段階でのみ延伸処理をして
いたときとは違って、延伸処理を無理なくできるばかり
か、炭素繊維の物性、即ち引張強度、引張弾性率が飛躍
的に向上し、又圧縮強度も増大することを見出した。[0010] In the process of researching a method for manufacturing carbon fibers in a continuous firing process, the present inventors conducted a drawing process on a fiber bundle, including infusibility of a pitch fiber bundle, pre-carbonization of an infusible fiber bundle, and pre-carbonization of a non-fusible fiber bundle. The pitch fiber bundle is divided into stages of carbonization, and the pitch fiber bundle is made infusible by rapidly increasing the temperature to a temperature 30 to 100°C lower than the melting and breaking temperature of the fiber bundle in an oxidizing gas atmosphere. The pre-carbonization of the infusible fiber bundle is similarly rapidly carried out in an inert gas atmosphere to a temperature 30 to 100°C lower than the melting and breaking temperature of the fiber bundle. The process is carried out by raising the temperature and heat-treating the fiber bundle in an extremely short time while simultaneously stretching the fiber bundle, and further carbonizing the pre-carbonized fiber bundle.
If the fiber bundle is stretched while being stretched, unlike the conventional stretching process, which was carried out only during the preliminary carbonization stage of the infusible fiber bundle, the stretching process can be carried out easily, and the carbon fiber It has been found that the physical properties of the material, namely tensile strength and tensile modulus, are dramatically improved, and the compressive strength is also increased.
【００１１】更に驚いたことには、上記のような熱処理
及びこれと同時の延伸処理（以下、必要に応じて延伸熱
処理という）を不融化時及び予備炭化時に行なった場合
には、ピッチ繊維束の不融化炉内及び不融化繊維束の予
備炭化炉内での断糸を回避することができ、不融化、予
備炭化の際の歩留りも向上できることが分かった。[0011] Furthermore, it is surprising that when the above-mentioned heat treatment and simultaneous stretching treatment (hereinafter referred to as stretching heat treatment as necessary) are performed during infusibility and pre-carbonization, the pitch fiber bundle It has been found that yarn breakage in the infusible furnace and in the pre-carbonization furnace of the infusible fiber bundle can be avoided, and the yield during infusibility and pre-carbonization can also be improved.
【００１２】本発明は、斯る知見に基づきなされたもの
である。The present invention has been made based on this knowledge.
【００１３】従って本発明の目的は、ピッチ繊維束の不
融化炉内及び不融化繊維束の予備炭化炉内での断糸を防
止し、ピッチ繊維束の不融化、不融化繊維束の予備炭化
及び予備炭化繊維束の炭化の段階で効果的に延伸処理を
することにより、高引張強度、高引張弾性率及び高圧縮
強度を有した高品質の炭素繊維を得ることができるピッ
チ系炭素繊維の製造方法を提供することである。Therefore, an object of the present invention is to prevent yarn breakage in a pitch fiber bundle infusible furnace and in a pre-carbonization furnace for an infusible fiber bundle, and to prevent the pitch fiber bundle from becoming infusible and the infusible fiber bundle to be pre-carbonized. and pitch-based carbon fibers that can obtain high-quality carbon fibers with high tensile strength, high tensile modulus, and high compressive strength by effectively stretching the pre-carbonized fiber bundle at the carbonization stage. An object of the present invention is to provide a manufacturing method.
【００１４】[0014]
【課題を解決するための手段】上記目的は本発明に係る
ピッチ系炭素繊維及び黒鉛繊維の製造方法にて達成され
る。要約すれば本発明は、紡糸、集束されたピッチ繊維
束を不融化し、前記不融化された不融化繊維束を予備炭
化し、前記予備炭化された予備炭化繊維束を炭化し、必
要に応じて更に黒鉛化することからなるピッチ系炭素繊
維及び黒鉛繊維の製造方法において、前記ピッチ繊維束
の不融化を、酸化性ガス雰囲気中で繊維束の溶融破断温
度よりも３０〜１００℃低い温度まで１００〜５０００
℃／分の速度で昇温して、繊維束を１〜３００秒の極く
短時間で熱処理しながら延伸率５〜１００％の延伸処理
をすることにより行ない、前記不融化繊維束の予備炭化
を、不活性ガス雰囲気中で繊維束の溶融破断温度よりも
３０〜１００℃低い温度まで１００〜５０００℃／分の
速度で昇温して、繊維束を１〜３００秒の極く短時間で
熱処理しながら延伸率５〜１００％の延伸処理をするこ
とにより行ない、更に前記予備炭化繊維束の炭化を、繊
維束に延伸率１〜３０％の延伸処理をしながら行なうこ
とを特徴とするピッチ系炭素繊維及び黒鉛繊維の製造方
法である。[Means for Solving the Problems] The above objects are achieved by a method for producing pitch-based carbon fibers and graphite fibers according to the present invention. To summarize, the present invention infusibleizes a spun and bundled pitch fiber bundle, pre-carbonizes the infusible infusible fiber bundle, carbonizes the pre-carbonized pre-carbonized fiber bundle, and optionally In the method for producing pitch-based carbon fibers and graphite fibers, which comprises further graphitizing the pitch fiber bundle, the pitch fiber bundle is made infusible to a temperature 30 to 100 °C lower than the melting and breaking temperature of the fiber bundle in an oxidizing gas atmosphere. 100-5000
Preliminary carbonization of the infusible fiber bundle is carried out by elevating the temperature at a rate of °C/min, heat-treating the fiber bundle in an extremely short time of 1 to 300 seconds, and stretching the fiber bundle at a stretching rate of 5 to 100%. is heated at a rate of 100 to 5000°C/min to a temperature 30 to 100°C lower than the melting and breaking temperature of the fiber bundle in an inert gas atmosphere, and the fiber bundle is heated in an extremely short time of 1 to 300 seconds. A pitch characterized in that the carbonization of the pre-carbonized fiber bundle is carried out by subjecting the fiber bundle to a stretching treatment at a stretching rate of 1 to 30% while being heat-treated. This is a method for producing carbon fibers and graphite fibers.
【００１５】上記において、繊維束の溶融破断温度とは
、窒素雰囲気の一定温度（例えば４００℃）に保持され
た加熱部長さ２ｍの炉に繊維束を１０ｍ／分で通糸して
（繊維束の昇温速度５０００℃／分に相当）、繊維の溶
融により繊維束が切断する温度をいう。繊維束の溶融破
断温度は、切断した繊維束を目視により観察して繊維に
溶融が認められたときの温度として得ることができるが
、正確には走査型電子顕微鏡による観察で繊維の溶融を
認めたときの温度として求められる。[0015] In the above, the melting and breaking temperature of a fiber bundle is defined as the temperature at which the fiber bundle is threaded at a rate of 10 m/min through a furnace with a heated section length of 2 m maintained at a constant temperature (for example, 400°C) in a nitrogen atmosphere. (equivalent to a heating rate of 5000°C/min), which is the temperature at which the fiber bundle is cut by melting the fibers. The melting and breaking temperature of a fiber bundle can be obtained as the temperature at which melting of the fibers is observed by visually observing the cut fiber bundle, but more precisely, it is the temperature at which melting of the fibers is observed by observation using a scanning electron microscope. It is determined as the temperature when
【００１６】又昇温速度とは、炉の入り口温度から炉の
均熱部温度に繊維束が到達する時間から求めた値をいう
。[0016] The temperature increase rate is a value determined from the time it takes for the fiber bundle to reach the temperature at the soaking section of the furnace from the temperature at the entrance of the furnace.
【００１７】本発明においては、ピッチ繊維束を溶融破
断温度よりも３０〜１００℃低い温度まで急速に昇温し
て、熱処理及びこれと同時の延伸処理からなる短時間の
延伸熱処理をすることにより、ピッチ繊維束の不融化を
行なうが、好ましくは溶融破断温度よりも４０〜８０℃
低い温度までの昇温とすることがよい。昇温速度は１０
０〜５０００℃／分の速度が用いられるが、好ましくは
５００〜４０００℃／分である。ピッチ繊維束の延伸率
は５〜１００％が用いられるが、好ましくは１０〜８０
％である。In the present invention, the pitch fiber bundle is heated rapidly to a temperature 30 to 100° C. lower than the melt breakage temperature, and subjected to a short-time drawing heat treatment consisting of heat treatment and simultaneous drawing treatment. , the pitch fiber bundle is rendered infusible, preferably at a temperature of 40 to 80°C higher than the melt breakage temperature.
It is preferable to raise the temperature to a low temperature. The heating rate is 10
Rates of 0-5000°C/min are used, preferably 500-4000°C/min. The stretching ratio of the pitch fiber bundle is 5 to 100%, preferably 10 to 80%.
%.
【００１８】同様に、不融化繊維束を溶融破断温度より
も３０〜１００℃低い温度まで急速に昇温して、熱処理
及びこれと同時の延伸処理からなる短時間の延伸熱処理
をすることにより、不融化繊維束の予備炭化を行なうが
、同様に、好ましくは溶融破断温度よりも４０〜８０℃
低い温度までの昇温とすることがよい。同様に、昇温速
度は１００〜５０００℃／分の速度が用いられ、好まし
くは５００〜４０００℃／分であり、不融化繊維束の延
伸率は５〜１００％、好ましくは１０〜８０％である。Similarly, by rapidly raising the temperature of the infusible fiber bundle to a temperature 30 to 100° C. lower than the melt breakage temperature and carrying out a short-time stretching heat treatment consisting of heat treatment and simultaneous stretching treatment, Preliminary carbonization of the infusible fiber bundle is performed, and similarly, preferably at a temperature of 40 to 80°C below the melt breaking temperature.
It is preferable to raise the temperature to a low temperature. Similarly, the heating rate is 100 to 5000°C/min, preferably 500 to 4000°C/min, and the stretching rate of the infusible fiber bundle is 5 to 100%, preferably 10 to 80%. be.
【００１９】又このようにして得られた予備炭化繊維束
の炭化を延伸処理しながら行なうが、その延伸処理は繊
維束に延伸率１〜３０％で行なうことが好ましい。The pre-carbonized fiber bundle thus obtained is carbonized while being subjected to stretching treatment, and the stretching treatment is preferably carried out at a stretching ratio of 1 to 30%.
【００２０】本発明によれば、上記のように、繊維束の
延伸処理をピッチ繊維束の不融化、不融化繊維束の予備
炭化及び不融化繊維束の炭化の段階に分けて行ない、且
つそのピッチ繊維束の不融化を、酸化性ガス雰囲気中で
繊維束の溶融破断温度よりも３０〜１００℃低い温度ま
で急速に昇温して、短時間の熱処理及び延伸処理する条
件により行ない、不融化繊維束の予備炭化を、不活性ガ
ス雰囲気中で繊維束の溶融破断温度よりも３０〜１００
℃低い温度まで急速に昇温して、短時間の熱処理及び延
伸処理する条件で行ない、更に予備炭化繊維の炭化を延
伸処理を加えた条件で行なうので、得られる炭素繊維の
物性は、引張強度及び引張弾性率が飛躍的に向上し、又
圧縮強度も増大したものになる。According to the present invention, as described above, the drawing process of the fiber bundle is carried out in the stages of infusibility of the pitch fiber bundle, preliminary carbonization of the infusible fiber bundle, and carbonization of the infusible fiber bundle, and The pitch fiber bundle is made infusible by rapidly raising the temperature in an oxidizing gas atmosphere to a temperature 30 to 100 degrees Celsius lower than the melting and breaking temperature of the fiber bundle, followed by short-time heat treatment and stretching. The fiber bundle is pre-carbonized in an inert gas atmosphere at a temperature of 30 to 100° below the melting and breaking temperature of the fiber bundle.
The temperature is rapidly raised to a low temperature of °C, and the heat treatment and stretching treatment are carried out for a short time.The carbonization of the pre-carbonized fibers is then carried out under conditions in which stretching treatment is added.The physical properties of the obtained carbon fibers are as follows: The tensile modulus is dramatically improved, and the compressive strength is also increased.
【００２１】[0021]
【実施例】以下、本発明の実施例について詳細に説明す
る。[Examples] Examples of the present invention will be described in detail below.
【００２２】先ず、炭素質ピッチは当業者には周知の方
法によって紡糸できる。例えば、石油系ピッチ、石炭系
ピッチ、芳香族炭化水素類を原料とするピッチ等の炭素
繊維の製造に適した炭素質ピッチを加熱溶融して１〜３
０００本、好ましくは５０〜１０００本のフィラメント
を紡糸し、各フィラメントには通常使用されているオイ
リングローラを使用して集束剤を付与して、これら多数
のフィラメントを集束し、１本の糸条としてボビンに巻
取られる。First, carbonaceous pitch can be spun by methods well known to those skilled in the art. For example, by heating and melting carbonaceous pitch suitable for manufacturing carbon fiber, such as petroleum pitch, coal pitch, pitch made from aromatic hydrocarbons, etc.
000 filaments, preferably 50 to 1000 filaments are spun, and a sizing agent is applied to each filament using a commonly used oiling roller to bundle these many filaments into a single yarn. It is wound onto a bobbin.
【００２３】集束剤としては、例えば水、エチルアルコ
ール、イソプロピルアルコール、ｎ−プロピルアルコー
ル、ブチルアルコール、等のアルコール類又は粘度５〜
１０００ｃｓｔ（２５℃）のジメチルポリシロキサン、
アルキルフェニルポリシロキサン等を、低沸点のシリコ
ーン油（ポリシロキサン）又はパラフィン油等の溶剤で
稀釈したもの、又は乳化剤を入れて水に分散させたもの
；同様にグラファイト又はポリエチレングリコールやヒ
ンダードエステル類を分散させたもの；界面活性剤を水
で稀釈したもの；その他通常の繊維、例えばポリエステ
ル繊維に使用される各種油剤の内ピッチ繊維を犯さない
ものを使用することができる。Examples of the sizing agent include water, alcohols such as ethyl alcohol, isopropyl alcohol, n-propyl alcohol, butyl alcohol, or sizing agents with a viscosity of 5 to 5.
1000cst (25°C) dimethylpolysiloxane,
Alkylphenylpolysiloxane etc. diluted with a low boiling point silicone oil (polysiloxane) or a solvent such as paraffin oil, or dispersed in water with an emulsifier added; Similarly, graphite, polyethylene glycol or hindered esters Dispersions of surfactants; surfactants diluted with water; and other oils that do not harm pitch fibers among the various oils used for ordinary fibers, such as polyester fibers, can be used.
【００２４】集束剤のピッチ繊維への付与量は、通常０
．０１〜１０重量％とされるが、特に０．０５〜５重量
％が好ましい。[0024] The amount of sizing agent applied to the pitch fibers is usually 0.
．． 0.01 to 10% by weight, particularly preferably 0.05 to 5% by weight.
【００２５】上述のようにして一旦ボビンに巻取られた
多数のフィラメントから成る糸条は、複数個の、例えば
２〜５０個のボビンを同時に解舒することによって、又
は複数回に分けて、例えば１回目は２〜１０本を、次い
で残余分をといつたように、解舒合糸を繰返し行なうこ
とによつて、２〜５０本の糸条を合束（合糸）し、１０
０〜１０００００本、好ましくは５００〜１００００本
のフィラメントからピッチ繊維束（以後必要に応じて単
に「ピッチ繊維」という。）が製造され、他のボビンに
巻取られる。[0025] The yarn consisting of a large number of filaments once wound onto a bobbin as described above can be unwound by simultaneously unwinding a plurality of bobbins, for example 2 to 50 bobbins, or by dividing it into multiple times. For example, by unwinding and doubling 2 to 10 yarns the first time and then combing the remaining yarn, 2 to 50 yarns are bundled (paired), and 10
A pitch fiber bundle (hereinafter simply referred to as "pitch fiber" if necessary) is produced from 0 to 100,000 filaments, preferably 500 to 10,000 filaments, and wound onto another bobbin.
【００２６】斯る合糸時に、不融化時及び予備炭化時の
処理を考慮してピッチ繊維に耐熱性の油剤が付与される
。耐熱性の油剤としては、アルキルフェニルポリシロキ
サンが好ましく、フェニル基を５〜８０％、好ましくは
１０〜５０％含み、又、アルキル基としてはメチル基、
エチル基、プロピル基が好ましく、同一分子に２種以上
のアルキル基を有していても良い。又、粘度は２５℃に
て１０〜１０００ｃｓｔのものが使用される。更に後述
するような酸化防止剤を添加することもできる。[0026] At the time of such yarn doubling, a heat-resistant oil agent is applied to the pitch fibers in consideration of treatments during infusibility and preliminary carbonization. As the heat-resistant oil agent, alkylphenylpolysiloxane is preferable, containing 5 to 80%, preferably 10 to 50%, of phenyl groups, and the alkyl groups include methyl groups,
Ethyl groups and propyl groups are preferred, and the same molecule may contain two or more types of alkyl groups. Further, the viscosity used is 10 to 1000 cst at 25°C. Furthermore, an antioxidant as described later can also be added.
【００２７】他の好ましい油剤としては、ジメチルポリ
シロキサンに酸化防止剤を入れたものが使用可能であり
、粘度としては２５℃で５〜１０００ｃｓｔのものが好
ましい。酸化防止剤としては、アミン類、有機セレン化
合物、フェノール類等、例えばフェニル−α−ナフチル
アミン、ジラウリルセレナイド、フェノチアジン、鉄オ
クトレート等を挙げることができる。これらの酸化防止
剤は、上述したように、更に耐熱性を高める目的で上記
アルキルフェニルポリシロキサンに添加することも可能
である。Another preferred oil agent that can be used is dimethylpolysiloxane containing an antioxidant, and preferably has a viscosity of 5 to 1000 cst at 25°C. Examples of the antioxidant include amines, organic selenium compounds, phenols, and the like, such as phenyl-α-naphthylamine, dilauryl selenide, phenothiazine, and iron octolate. As mentioned above, these antioxidants can also be added to the alkylphenylpolysiloxane for the purpose of further increasing heat resistance.
【００２８】更に、好ましい油剤としては、上記各油剤
を沸点が６００℃以下の界面活性剤を用いて、乳化した
ものを使用することもできる。このとき界面活性剤とし
ては、ポリオキシエチレンアルキルエーテル、ポリオキ
シエチレンアルキルエステル、ポリオキシエチレン変性
シリコーン、ポリオキシアルキレン変性シリコーン等を
使用し得る。[0028] Furthermore, as a preferable oil agent, it is also possible to use one obtained by emulsifying each of the above-mentioned oil agents using a surfactant having a boiling point of 600°C or less. At this time, as the surfactant, polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, polyoxyethylene-modified silicone, polyoxyalkylene-modified silicone, etc. can be used.
【００２９】これら油剤は、ローラ接触、スプレー塗布
、泡沫塗布等により、ピッチ繊維に０．０１〜１０重量
％、好ましくは０．０５〜５重量％が付与される。These oil agents are applied to the pitch fibers in an amount of 0.01 to 10% by weight, preferably 0.05 to 5% by weight, by roller contact, spray coating, foam coating, or the like.
【００３０】上述のように、合糸されたピッチ繊維に耐
熱性油剤を付与することにより、該ピッチ繊維は強度が
著しく強くなり糸扱い性が極めて向上する。As mentioned above, by applying a heat-resistant oil agent to the pitch fibers that have been doubled, the strength of the pitch fibers becomes significantly stronger and the yarn handling properties are greatly improved.
【００３１】以上の如くにして製造されたピッチ繊維を
ボビンより解舒して、不融化炉へと送給する。The pitch fibers produced as described above are unwound from a bobbin and sent to an infusibility furnace.
【００３２】不融化炉内は酸化性ガス雰囲気とされ、不
融化炉内には空気、酸素、空気と酸素又は空気と窒素の
混合ガス等の酸化性ガスが供給されるが、好ましいガス
としては酸素濃度３０〜９０％の富酸素ガスが使用され
る。場合によっては、上記のガスにＮＯｘ、ＳＯｘ、Ｃ
ｌ２ などを含有させた混合ガスを用いてもよい。The interior of the infusibility furnace is an oxidizing gas atmosphere, and an oxidizing gas such as air, oxygen, a mixed gas of air and oxygen, or air and nitrogen is supplied to the infusibility furnace. Oxygen-rich gas with an oxygen concentration of 30-90% is used. In some cases, the above gases include NOx, SOx, C
A mixed gas containing l2 or the like may also be used.
【００３３】不融化は１５０〜３５０℃の温度で行なわ
れるが、本発明では、その不融化を、ピッチ繊維束の溶
融破断温度より３０〜１００℃低い温度まで１００〜５
０００℃／分の速度で昇温して、繊維束を１〜３００秒
の極く短時間の延伸熱処理することにより行なう。[0033] Infusibility is carried out at a temperature of 150 to 350°C, but in the present invention, the infusibility is carried out at a temperature of 100 to 50°C to a temperature 30 to 100°C lower than the melt breakage temperature of the pitch fiber bundle.
This is carried out by heating the fiber bundle at a rate of 000° C./min and subjecting the fiber bundle to a very short stretching heat treatment of 1 to 300 seconds.
【００３４】上記の延伸熱処理は、例えば２５０℃とい
うような定温炉で行なってもよく、炉入り口部から出口
部にかけて１８０℃、２２０℃、２５０℃、２８０℃、
３１０℃というように、段階的に高くした温度が保持さ
れた温度傾斜炉で行なってもよい。[0034] The above-mentioned stretching heat treatment may be carried out in a fixed temperature furnace, for example, at 250°C, and the temperatures from the furnace entrance to the exit are 180°C, 220°C, 250°C, 280°C,
It may be carried out in a temperature gradient furnace in which the temperature is maintained at a stepwise increase, such as 310°C.
【００３５】本発明においては、ピッチ繊維束の溶融破
断温度よりも３０〜１００℃低い温度まで急速に昇温し
て延伸熱処理するが、好ましくは溶融破断温度より４０
〜８０℃低い温度がよい。上記の昇温が軟化断温度より
３０℃低い温度を超える高い温度まで行なわれると、繊
維束に融膠着が起こって繊維束が破断するので、好まし
くない。又上記の昇温が溶融破断温度よりも１００℃低
い温度未満の低い温度までであると、繊維束の延伸が困
難になるので、同様に好ましくない。In the present invention, the stretching heat treatment is carried out by rapidly raising the temperature to a temperature 30 to 100° C. lower than the melt breaking temperature of the pitch fiber bundle, preferably 40° C. lower than the melt breaking temperature of the pitch fiber bundle.
A temperature lower than ~80°C is preferable. If the temperature is increased to a temperature higher than 30° C. lower than the softening break temperature, the fiber bundle will become fused and stuck, and the fiber bundle will break, which is not preferable. Furthermore, if the temperature is increased to a low temperature that is less than 100° C. lower than the melt breakage temperature, it becomes difficult to draw the fiber bundle, which is similarly undesirable.
【００３６】上記の溶融破断温度よりも３０〜１００℃
低い温度までのピッチ繊維束の昇温速度は、１００〜５
０００℃／分の速度が用いられるが、好ましくは５００
〜４０００℃／分である。昇温速度が１００℃／分未満
の場合、不融化が進み十分な延伸ができにくくなり、逆
に５０００℃／分を超える場合、昇温が速すぎて繊維束
の通糸速度を速めなければならず、操作上の問題が出て
来、やはり好ましくない。[0036] 30 to 100°C higher than the above melt rupture temperature
The heating rate of the pitch fiber bundle to a low temperature is 100-5
A rate of 000°C/min is used, preferably 500°C/min.
~4000°C/min. If the heating rate is less than 100°C/min, infusibility progresses and sufficient stretching becomes difficult, whereas if it exceeds 5000°C/min, the heating rate is too fast and the threading speed of the fiber bundle must be increased. This is not desirable, as it causes operational problems.
【００３７】延伸熱処理の時間は、１〜３００秒が用い
られるが、好ましくは５〜１００秒℃の極く短時間であ
るのがよい。[0037] The time for the stretching heat treatment is 1 to 300 seconds, preferably a very short time of 5 to 100 seconds.
【００３８】延伸熱処理における延伸処理は、繊維束に
テンションを付与するか、２つのローラの差動により行
なわれ、いずれの方法によっても達成される。延伸時の
テンションは１フィラメント当たり０．００１〜０．２
０ｇが付与される。The drawing process in the drawing heat treatment is carried out by applying tension to the fiber bundle or by differentially moving two rollers, and can be achieved by either method. The tension during stretching is 0.001 to 0.2 per filament.
0g is given.
【００３９】繊維束の延伸率は５〜１００％、好ましく
は１０〜８０％とするのがよい。延伸率が５％未満では
十分な延伸効果が得られず、又１００％を超えると、延
伸による繊維のダメージが多くなるので好ましくない。The stretching ratio of the fiber bundle is preferably 5 to 100%, preferably 10 to 80%. If the stretching ratio is less than 5%, a sufficient stretching effect cannot be obtained, and if it exceeds 100%, the fibers will be damaged by stretching, which is not preferable.
【００４０】延熱伸処理は１回で行なってもよいが、例
えば２５０℃で１度延伸し、引き続き３００℃で延伸す
るというように複数回に分けて実施することもできる。
複数回に分けた場合には繊維のダメージが少なく、延伸
が容易にできるようになるので好ましい。[0040] The heat-stretching treatment may be carried out once, but it can also be carried out in multiple steps, for example, stretching once at 250°C and then stretching at 300°C. It is preferable to divide the process into multiple times because the fibers are less damaged and can be drawn easily.
【００４１】このようにして、不融化繊維束の酸素濃度
が７〜１２重量％になるように不融化される。[0041] In this way, the infusible fiber bundle is infusible so that the oxygen concentration becomes 7 to 12% by weight.
【００４２】このような延伸熱処理による不融化の結果
、繊維束の配向性が改善され、得られる炭素繊維の物性
が向上する。延伸熱処理による不融化は１回又は複数回
繰り返して不融化を終了としてもよいが、その後に延伸
処理のない通常の不融化を実施してもよい。As a result of the infusibility caused by such drawing heat treatment, the orientation of the fiber bundles is improved, and the physical properties of the resulting carbon fibers are improved. Infusibility by stretching heat treatment may be repeated once or multiple times to complete infusibility, but after that, normal infusibility without stretching treatment may be performed.
【００４３】不融化炉で不融化された不融化繊維束は、
連続的に予備炭化炉内に導入され、予備炭化される。The infusible fiber bundle made infusible in the infusible furnace is
It is continuously introduced into a pre-carbonization furnace and pre-carbonized.
【００４４】予備炭化は、不活性ガス雰囲気下で実施さ
れ、好ましいガスとしては窒素ガス、アルゴンガスが使
用される。予備炭化は３００〜１３００℃の温度で行な
われるが、本発明では、予備炭化の際にも、不融化繊維
束の溶融破断温度より３０〜１００℃低い温度まで１０
０〜５０００℃／分の速度で昇温して、繊維束を１〜３
００秒の極く短時間の延伸熱処理する。Preliminary carbonization is carried out under an inert gas atmosphere, with nitrogen gas and argon gas being preferably used. Preliminary carbonization is carried out at a temperature of 300 to 1300°C, but in the present invention, even during preliminary carbonization, the temperature is 10 to 100°C lower than the melt breakage temperature of the infusible fiber bundle.
The fiber bundle is heated at a rate of 0 to 5000°C/min to
A very short stretching heat treatment of 00 seconds is applied.
【００４５】上記の延伸熱処理は、例えば４００℃とい
うような定温炉で行なってもよく、炉入り口部から出口
部にかけて３００℃、４００℃、５００℃、６００℃、
１１００℃というように、段階的に高くした温度が保持
された温度傾斜炉で行なってもよい。[0045] The above-mentioned stretching heat treatment may be carried out in a constant temperature furnace, for example, at 400°C.
It may be carried out in a temperature gradient furnace in which the temperature is maintained at a stepwise increase, such as 1100°C.
【００４６】不融化繊維束の延伸熱処理も同様、不融化
繊維束の溶融破断温度よりも３０〜１００℃低い温度ま
で急速に昇温して延伸熱処理するが、好ましくは溶融破
断温度より４０〜８０℃低い温度がよい。上記の昇温が
溶融破断温度より３０℃低い温度を超える高い温度まで
行なわれると、繊維束に融膠着が起こって繊維束が破断
するので、好ましくない。又上記の昇温が溶融破断温度
よりも１００℃低い温度未満の低い温度までであると、
繊維束の延伸が困難になるので、同様に好ましくない。Similarly, the drawing heat treatment of the infusible fiber bundle is carried out by rapidly raising the temperature to a temperature 30 to 100°C lower than the melt breaking temperature of the infusible fiber bundle, preferably 40 to 80°C lower than the melt breaking temperature of the infusible fiber bundle. A lower temperature is better. If the temperature is increased to a temperature higher than 30° C. lower than the melting and breaking temperature, the fiber bundle will become fused and stuck, and the fiber bundle will break, which is not preferable. Further, the above temperature increase is to a low temperature that is less than 100 ° C lower than the melt rupture temperature,
This is also not preferred since it makes it difficult to draw the fiber bundle.
【００４７】上記の溶融破断温度よりも３０〜１００℃
低い温度までの繊維束の昇温速度は、同様に、１００〜
５０００℃／分の速度が用いられ、好ましくは５００〜
４０００℃／分である。昇温速度が１００℃／分未満の
場合、繊維組織の熱重合や炭化が一部進みながら焼成さ
れるので十分な延伸ができにくくなり、逆に５０００℃
／分を超える場合、昇温が速すぎて繊維束の通糸速度を
速めなければならず、繊維束の巻取り速度に問題が出て
来、やはり好ましくない。[0047] 30 to 100°C higher than the above melt rupture temperature
Similarly, the heating rate of the fiber bundle to a low temperature is 100~
A rate of 5000°C/min is used, preferably 500°C/min.
4000°C/min. If the temperature increase rate is less than 100°C/min, the fiber structure will undergo partial thermal polymerization and carbonization during firing, making it difficult to achieve sufficient stretching.
If it exceeds 1/min, the temperature rise is too fast and the threading speed of the fiber bundle must be increased, which poses a problem in the winding speed of the fiber bundle, which is also not preferable.
【００４８】延伸熱処理の時間は、１〜３００秒が用い
られるが、好ましくは５〜２００秒℃の極く短時間であ
るのがよい。[0048] The time for the stretching heat treatment is 1 to 300 seconds, preferably a very short time of 5 to 200 seconds.
【００４９】延伸熱処理における延伸処理は、不融化繊
維束にテンションを付与するか、２つのローラの差動に
より行なわれ、いずれの方法によっても達成される。延
伸時のテンションは１フィラメント当たり０．００１〜
０．２０ｇが付与される。The stretching process in the stretching heat treatment can be accomplished by applying tension to the infusible fiber bundle or by differentially moving two rollers. Tension during stretching is 0.001~ per filament
0.20g is given.
【００５０】繊維束の延伸率は５〜１００％、好ましく
は１０〜８０％とするのがよい。延伸率が５％未満では
十分な延伸効果が得られず、又１００％を超えると、延
伸による繊維のダメージが多くなるので好ましくない。The stretching ratio of the fiber bundle is preferably 5 to 100%, preferably 10 to 80%. If the stretching ratio is less than 5%, a sufficient stretching effect cannot be obtained, and if it exceeds 100%, the fibers will be damaged by stretching, which is not preferable.
【００５１】延伸熱処理は１回で行なってもよいが、例
えば４００℃で１度延伸し、引き続き５００℃で延伸す
るというように複数回に分けて実施することもできる。
複数回に分けた場合には繊維のダメージが少なく、延伸
が容易にできるようになるので好ましい。[0051] The stretching heat treatment may be carried out once, but it can also be carried out in multiple steps, for example, stretching once at 400°C and then stretching at 500°C. It is preferable to divide the process into multiple times because the fibers are less damaged and can be drawn easily.
【００５２】上記の延伸熱処理終了後、引き続き、不融
化繊維束に対し延伸処理のない通常の予備炭化処理を行
なってもよい。[0052] After the above-mentioned drawing heat treatment is completed, the infusible fiber bundle may be subsequently subjected to a normal preliminary carbonization treatment without drawing treatment.
【００５３】従来であると、不融化繊維束は脆弱で、不
融化繊維束の予備炭化で繊維の切断や毛羽立ちが発生す
るのを避けようとすれば、予備炭化工程だけは繊維束に
テンションを掛けないか或いは掛けても取扱性が悪化し
ない最小限のテンションとして行なわざるを得ない状態
で、まして予備炭化の段階で積極的にテンションを掛け
て繊維束の延伸処理を加えることによっては、繊維の引
張強度、引張弾性率、圧縮強度の向上を図ることは不可
能であった。Conventionally, infusible fiber bundles are fragile, and in order to avoid cutting or fuzzing of the fibers during pre-carbonization of the infusible fiber bundles, it is necessary to apply tension to the fiber bundles only during the pre-carbonization process. If tension is not applied at all, or if tension is applied at a minimum level that does not deteriorate handling properties, it is even more difficult to apply tension to the fiber bundle during the pre-carbonization stage to draw the fiber bundle. It has been impossible to improve the tensile strength, tensile modulus, and compressive strength of.
【００５４】これが、本発明では、繊維束の延伸処理を
不融化、予備炭化及び炭化の段階に分けて行ない、且つ
その不融化及び予備炭化を、それぞれの繊維束の溶融破
断温度よりも３０〜１００℃低い温度まで急速に昇温し
て、短時間の延伸熱処理をすることにより行なうので、
ピッチ繊維束及び不融化繊維束の炉内での切断や毛羽立
ちの発生を防止するだけでなく、テンションを掛けて延
伸処理しながら不融化及び予備炭化をすることができる
。そして不融化、予備炭化及び炭化の際、特に不融化繊
維束の予備炭化の際の繊維束への積極的なテンションを
掛けた延伸処理により、繊維組織の配列性が高まり、最
終的に得られる炭素繊維の引張強度、引張弾性率及び圧
縮強度を有効に向上することが可能となる。However, in the present invention, the drawing process of the fiber bundle is carried out in stages of infusibility, pre-carbonization and carbonization, and the infusibility and pre-carbonization are carried out at a temperature of 30 to 30°C below the melting and breaking temperature of each fiber bundle. This is done by rapidly raising the temperature to a temperature 100°C lower and performing a short stretching heat treatment.
Not only can pitch fiber bundles and infusible fiber bundles be prevented from being cut or fluffed in the furnace, but also they can be infusible and pre-carbonized while being stretched under tension. Then, during infusibility, pre-carbonization, and carbonization, especially during pre-carbonization of the infusible fiber bundle, stretching treatment that applies active tension to the fiber bundle increases the alignment of the fiber structure, resulting in the final result. It becomes possible to effectively improve the tensile strength, tensile modulus, and compressive strength of carbon fibers.
【００５５】以上のようにして不融化繊維束の予備炭化
を行なったら、得られた予備炭化繊維束は、続いて炭化
炉で不活性ガス雰囲気下にて温度１５００〜２０００℃
まで加熱して炭化し、必要に応じて３０００℃まで加熱
して黒鉛化される。After pre-carbonizing the infusible fiber bundle as described above, the obtained pre-carbonized fiber bundle is then heated in a carbonization furnace at a temperature of 1500 to 2000°C under an inert gas atmosphere.
It is heated to 3,000°C to carbonize, and if necessary, to graphitize by heating to 3,000°C.
【００５６】本発明によれば、この炭化又は炭化及び黒
鉛化の際に、更に繊維束に１フィラメント当たり０．０
５〜３．３ｇ（３０００フィラメントの繊維束に対して
１５０〜１０，０００ｇ）の高いテンションを掛けて延
伸率１〜３０％の延伸処理が行なわれる。これにより繊
維組織の配列性が更に高まり、得られる炭素繊維及び黒
鉛繊維は、繊維の切断や毛羽立ちがなく、且つ引張強度
、引張弾性率及び圧縮強度が更に向上したものとなる。According to the present invention, during the carbonization or carbonization and graphitization, the fiber bundle is further coated with 0.0 per filament.
Stretching is performed at a stretching rate of 1 to 30% by applying a high tension of 5 to 3.3 g (150 to 10,000 g for a fiber bundle of 3000 filaments). This further improves the alignment of the fiber structure, and the resulting carbon fibers and graphite fibers are free from fiber breakage and fluffing, and have further improved tensile strength, tensile modulus, and compressive strength.
【００５７】更に、上記のような延伸処理をすることに
より高度な延伸が可能となるので、糸系が４〜１０μｍ
の細径のピッチ系炭素繊維を容易に得ることができる。
その結果、炭素繊維を複合材料にする際の糸扱い性が良
好で、且つ複合材料での物性が発現し易い糸とすること
ができる。Furthermore, by carrying out the above-mentioned drawing process, a high degree of drawing becomes possible, so that the yarn system can be
pitch-based carbon fibers with a small diameter can be easily obtained. As a result, the yarn can be made into a yarn that has good yarn handling properties when made into a composite material from carbon fibers, and that can easily exhibit the physical properties of a composite material.
【００５８】本発明で用いる原料炭素質ピッチは、公知
の原料、例えば石油系の各種重質油、熱分解タール、接
触分解タール、石炭の乾留によって得られる重質油、タ
ールなどを出発原料として、その熱分解重縮合によって
得られるメソフェースピッチ（光学的異方性ピッチ）、
芳香族炭化水素類を原料とするメソフェースピッチ、光
学的異方性相と光学的等方性相を含有するピッチ或いは
光学的等方性ピッチであってもよい。例えば、超高強度
の高性能炭素繊維を、熱分解重縮合によって得られたメ
ソフェースピッチから製造する場合、メソフェース含有
量７０〜１００％のメソフェースピッチが好ましく、特
に実質的に１００％のメソフェースを含有するメソフェ
ースピッチが最も好ましい。The raw material carbonaceous pitch used in the present invention is prepared from known raw materials such as various petroleum-based heavy oils, pyrolysis tar, catalytic cracking tar, heavy oil and tar obtained by carbonization of coal, etc. , mesophase pitch (optically anisotropic pitch) obtained by its thermal decomposition polycondensation,
It may be a mesoface pitch made from aromatic hydrocarbons, a pitch containing an optically anisotropic phase and an optically isotropic phase, or an optically isotropic pitch. For example, when ultra-high-strength, high-performance carbon fibers are produced from mesoface pitch obtained by pyrolysis polycondensation, mesoface pitch with a mesoface content of 70 to 100% is preferred, particularly substantially 100% mesoface pitch. Most preferred is a mesoface pitch containing.
【００５９】次に、本発明に係る炭素繊維の製造方法を
具体的な実施例に即して更に説明する。Next, the method for producing carbon fiber according to the present invention will be further explained based on specific examples.
【００６０】実施例１
光学的異方性相９７％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（ノズル孔径：直
径０．３ｍｍ）に通し、３４５℃で２００ｍｍＨｇの窒
素ガス圧で押し出して紡糸した。Example 1 Carbon fiber pitch consisting of 97% optically anisotropic phase was
The mixture was passed through a melt spinning machine (nozzle hole diameter: 0.3 mm in diameter) having a 0.00-hole spinneret, and extruded and spun at 345° C. under a nitrogen gas pressure of 200 mmHg.
【００６１】紡糸した５００本のフィラメントはエアー
サッカーで略集束してオイリングローラに導き、糸に対
して約０．２重量％の割合で集束用油剤を供給し、５０
０フィラメントから成るピッチ繊維を形成した。油剤と
しては、２５℃における粘度が１４ｃｓｔのメチルフェ
ニルポリシロキサンを使用した。The 500 spun filaments were approximately converged by an air sucker and guided to an oiling roller, and a convergence oil was supplied at a ratio of about 0.2% by weight to the yarn.
A pitch fiber consisting of 0 filaments was formed. As the oil agent, methylphenylpolysiloxane having a viscosity of 14 cst at 25° C. was used.
【００６２】該ピッチ繊維は、ノズル下部に設けた高速
で回転する直径２１０ｍｍ、幅２００ｍｍのステンレス
鋼製のボビンに巻き取り、約５００ｍ／分の巻き取り速
度で１０分間紡糸した。The pitch fibers were wound onto a stainless steel bobbin with a diameter of 210 mm and a width of 200 mm that was provided at the bottom of the nozzle and rotated at high speed, and spun for 10 minutes at a winding speed of about 500 m/min.
【００６３】次いで、ピッチ繊維を巻いた前記ボビン６
個を解舒し、そしてオイリングローラを使用して耐熱性
油剤を付与しながら合糸し、３０００フィラメントから
成るピッチ繊維（束）を形成し、他のステンレス製ボビ
ンに巻取つた。Next, the bobbin 6 wound with pitch fibers is
The fibers were unwound, and the fibers were combined using an oiling roller while applying a heat-resistant oil to form a pitch fiber (bundle) consisting of 3,000 filaments, which was wound onto another stainless steel bobbin.
【００６４】合糸時に油剤としては２５℃で４０ｃｓｔ
のメチルフェニルポリシロキサン（フェニル基含有量４
５モル％）を使用した。付与量は糸に対し０．５％であ
つた。[0064] As an oil agent during yarn doubling, use 40cst at 25°C.
of methylphenylpolysiloxane (phenyl group content 4
5 mol%) was used. The amount applied was 0.5% based on the yarn.
【００６５】このようにして得た、ボビン巻のピッチ繊
維束をボビンから解舒しつつ、炉入口温度１８０℃、炉
出口温度２２０℃の温度勾配を持つ富酸素雰囲気（酸素
／窒素＝６０／４０）の連続不融化炉に線状で連続的に
導入した。１８０℃から２２０℃への昇温速度は６℃／
分であった。While unwinding the bobbin-wound pitch fiber bundle thus obtained from the bobbin, an oxygen-rich atmosphere (oxygen/nitrogen = 60/ 40) was continuously introduced in a linear manner into the continuous infusibility furnace. The temperature increase rate from 180℃ to 220℃ is 6℃/
It was a minute.
【００６６】この延伸熱処理による延伸処理時間は（２
５）秒であった。繊維束には１フィラメント当たり（０
．００７）ｇのテンションが付与された。延伸率は（１
７）％であった。The stretching time for this stretching heat treatment is (2
5) It was seconds. The fiber bundle contains (0
．． 007) A tension of g was applied. The stretching ratio is (1
7)%.
【００６７】この２２０℃まで不融化前の延伸熱処理に
よる延伸処理をした繊維束の溶融破断温度は３００℃で
あった。この繊維束を、２５０℃（繊維束の溶融破断温
度よりも５０℃低い温度）の富酸素雰囲気（酸素／窒素
＝６０／４０）の不融化炉に３０００℃／分の昇温速度
で通糸して、延伸熱処理による不融化処理を施した。[0067] The melting and breaking temperature of the fiber bundle, which had been stretched to 220°C by the stretching heat treatment before infusibility, was 300°C. This fiber bundle is passed through an infusibility furnace in an oxygen-rich atmosphere (oxygen/nitrogen = 60/40) at 250°C (50°C lower than the melting and breaking temperature of the fiber bundle) at a heating rate of 3000°C/min. Then, the film was subjected to infusibility treatment by stretching heat treatment.
【００６８】この延伸熱処理による不融化処理時間は２
５秒であった。繊維束には１フィラメント当たり０．０
０６ｇのテンションが付与された。延伸率は１２％であ
った。[0068] The infusibility treatment time by this stretching heat treatment is 2
It was 5 seconds. 0.0 per filament for fiber bundles
A tension of 0.06 g was applied. The stretching ratio was 12%.
【００６９】その後、引き続き６℃／分で昇温して２９
５℃まで富酸素雰囲気（酸素／窒素＝６０／４０）の炉
で延伸のない通常の不融化を行なった。１時間の連続処
理を行なったが、その間炉内での繊維束の断糸は生じな
かった。[0069] Thereafter, the temperature was continued to increase at a rate of 6°C/min to 29°C.
Conventional infusibility without stretching was performed in a furnace in an oxygen-rich atmosphere (oxygen/nitrogen = 60/40) up to 5°C. Although the continuous treatment was carried out for one hour, no breakage of the fiber bundle occurred in the furnace during that time.
【００７０】この不融化繊維束を、４００℃（不融化繊
維束の溶融破断温度よりも５０℃低い温度）の窒素雰囲
気の予備炭化炉に３０００℃／分の昇温速度で通糸して
、熱処理と延伸処理を同時に行なう延伸熱処理を施した
。[0070] This infusible fiber bundle is passed through a pre-carbonization furnace in a nitrogen atmosphere at 400°C (a temperature 50°C lower than the melting failure temperature of the infusible fiber bundle) at a heating rate of 3000°C/min. Stretching heat treatment was performed in which heat treatment and stretching treatment were performed simultaneously.
【００７１】この延伸熱処理による予備炭化時間は２５
秒であった。繊維束には１フィラメント当たり０．００
６ｇのテンションが付与された。延伸率は１５％であっ
た。１時間の連続処理を行なったが、その間炉内での繊
維束の断糸は生じなかった。[0071] The preliminary carbonization time by this stretching heat treatment was 25
It was seconds. 0.00 per filament for fiber bundles
A tension of 6 g was applied. The stretching ratio was 15%. Although the continuous treatment was carried out for one hour, no breakage of the fiber bundle occurred in the furnace during that time.
【００７２】次いで上記のように処理された繊維束を更
に１００℃／分で１０００℃まで昇温して、テンション
を掛けずに通常の予備炭化をした。[0072] Next, the fiber bundle treated as described above was further heated to 1000°C at a rate of 100°C/min and subjected to normal preliminary carbonization without applying tension.
【００７３】このようにして得られた予備炭化繊維束を
、窒素ガス雰囲気中で１フィラメント当たり０．３３（
３０００フィラメントの繊維束に対し１０００ｇ）のテ
ンションをかけて延伸率２％の延伸処理をしながら１５
００℃まで昇温して、炭素繊維を得た。炭素繊維の糸径
は８．５μｍであり、引張強度は３．４ＧＰａ、引張弾
性率は３４０ＧＰａ、圧縮強度は１．２０ＧＰａであっ
た。The thus obtained pre-carbonized fiber bundle was heated at a rate of 0.33 (per filament) in a nitrogen gas atmosphere.
15 while applying a tension of 1000 g to a fiber bundle of 3000 filaments and stretching at a stretching rate of 2%.
The temperature was raised to 00°C to obtain carbon fibers. The carbon fiber thread diameter was 8.5 μm, the tensile strength was 3.4 GPa, the tensile modulus was 340 GPa, and the compressive strength was 1.20 GPa.
【００７４】又、炭素繊維をアルゴンガス雰囲気中で１
フィラメント当たり０．３ｇのテンションをかけて延伸
率１０％の延伸処理をしながら２５００℃まで昇温して
得た黒鉛炭素繊維は、糸径が８．２μｍであり、引張強
度は４．２ＧＰａ、引張弾性率は８２０ＧＰａ、圧縮強
度は０．４９ＧＰａであった。[0074] Also, carbon fibers were heated for 1 hour in an argon gas atmosphere.
The graphite carbon fiber obtained by heating up to 2500 ° C. while applying a tension of 0.3 g per filament and drawing at a drawing rate of 10% has a thread diameter of 8.2 μm and a tensile strength of 4.2 GPa. The tensile modulus was 820 GPa, and the compressive strength was 0.49 GPa.
【００７５】比較例１
実施例１において、予備炭化繊維束の炭化時に延伸処理
を加えない以外は、実施例１と同様に処理した。Comparative Example 1 The same procedure as in Example 1 was carried out except that the stretching treatment was not applied during carbonization of the pre-carbonized fiber bundle.
【００７６】その結果、予備炭化繊維を窒素ガス雰囲気
中で１５００℃まで昇温して得た炭素繊維の糸径は９．
８μｍであり、引張強度は３．３ＧＰａ、引張弾性率は
３３０ＧＰａ、圧縮強度は１．１２ＧＰａであった。As a result, the yarn diameter of the carbon fiber obtained by heating the pre-carbonized fiber to 1500°C in a nitrogen gas atmosphere was 9.
8 μm, tensile strength was 3.3 GPa, tensile modulus was 330 GPa, and compressive strength was 1.12 GPa.
【００７７】更に、炭素繊維をアルゴンガス雰囲気中で
２５００℃まで昇温して得た黒鉛炭素繊維は、糸径が９
．７μｍであり、引張強度は３．８ＧＰａ、引張弾性率
は３７０ＧＰａ、圧縮強度は０．４４ＧＰａであった。Furthermore, graphite carbon fiber obtained by heating carbon fiber to 2500°C in an argon gas atmosphere has a thread diameter of 9.
．． 7 μm, tensile strength was 3.8 GPa, tensile modulus was 370 GPa, and compressive strength was 0.44 GPa.
【００７８】比較例２
実施例１において、ピッチ繊維束の不融化時に延伸処理
を加えない以外は、実施例１と同様に処理した。Comparative Example 2 The same procedure as in Example 1 was carried out except that the stretching treatment was not applied during the infusibility of the pitch fiber bundle.
【００７９】予備炭化繊維を窒素ガス雰囲気中で１５０
０℃まで昇温して得た炭素繊維の糸径は９．８μｍであ
り、引張強度は３．２ＧＰａ、引張弾性率は３３０ＧＰ
ａ、圧縮強度は１．１０ＧＰａであった。[0079] The pre-carbonized fiber was heated to 150% in a nitrogen gas atmosphere.
The carbon fiber obtained by raising the temperature to 0°C has a thread diameter of 9.8 μm, a tensile strength of 3.2 GPa, and a tensile modulus of 330 GPa.
a. Compressive strength was 1.10 GPa.
【００８０】更に、炭素繊維をアルゴンガス雰囲気中で
２５００℃まで昇温して得た黒鉛炭素繊維は、糸径が９
．７μｍであり、引張強度は３．７ＧＰａ、引張弾性率
は３７０ＧＰａ、圧縮強度は１．０９ＧＰａであった。Furthermore, graphite carbon fiber obtained by heating carbon fiber to 2500°C in an argon gas atmosphere has a thread diameter of 9.
．． 7 μm, tensile strength was 3.7 GPa, tensile modulus was 370 GPa, and compressive strength was 1.09 GPa.
【００８１】比較例３
実施例１において、不融化繊維束の予備炭化時に延伸処
理を加えない以外は、実施例１と同様に処理した。Comparative Example 3 The same procedure as in Example 1 was carried out except that the stretching treatment was not applied during preliminary carbonization of the infusible fiber bundle.
【００８２】予備炭化繊維を窒素ガス雰囲気中で１５０
０℃まで昇温して得た炭素繊維の糸径は９．８μｍであ
り、引張強度は３．２０ＧＰａ、引張弾性率は３２０Ｇ
Ｐａ、圧縮強度は０．４５ＧＰａであった。[0082] The pre-carbonized fiber was heated to 150% in a nitrogen gas atmosphere.
The carbon fiber obtained by raising the temperature to 0°C has a thread diameter of 9.8 μm, a tensile strength of 3.20 GPa, and a tensile modulus of 320 G.
Pa, the compressive strength was 0.45 GPa.
【００８３】更に、炭素繊維をアルゴンガス雰囲気中で
２５００℃まで昇温して得た黒鉛炭素繊維は、糸径が９
．７μｍであり、引張強度は３．６ＧＰａ、引張弾性率
は３５０ＧＰａ、圧縮強度は０．４２ＧＰａであった。Furthermore, graphite carbon fiber obtained by heating carbon fiber to 2500°C in an argon gas atmosphere has a thread diameter of 9.
．． 7 μm, tensile strength was 3.6 GPa, tensile modulus was 350 GPa, and compressive strength was 0.42 GPa.
【００８４】比較例４
実施例１において、予備炭化炉の温度を４３０℃（繊維
束の溶融破断温度よりも２０℃低い温度）とした以外は
、実施例１と同様に処理した。Comparative Example 4 The same process as in Example 1 was carried out except that the temperature of the preliminary carbonization furnace was set at 430°C (20°C lower than the melting and breaking temperature of the fiber bundle).
【００８５】その結果、予備炭化炉内で断糸し、連続運
転することができなかった。[0085] As a result, the yarn broke in the preliminary carbonization furnace, making continuous operation impossible.
【００８６】比較例５
実施例１において、予備炭化炉の温度を３３０℃（繊維
束の溶融破断温度よりも１２０℃低い温度）とした以外
は、実施例１と同様に処理した。この場合は、繊維束の
延伸は起こらなかった。Comparative Example 5 The same procedure as in Example 1 was carried out except that the temperature of the preliminary carbonization furnace was 330° C. (120° C. lower than the melting and breaking temperature of the fiber bundle). In this case, no drawing of the fiber bundle occurred.
【００８７】その結果、予備炭化炉内で断糸することは
なく、１時間の連続運転ができた。しかし、この予備炭
化繊維を窒素ガス雰囲気中で１５００℃まで昇温して得
た炭素繊維の糸径は９．８μｍであり、引張強度は３．
２０ＧＰａ、引張弾性率は３２０ＧＰａ、圧縮強度は０
．４４ＧＰａであった。As a result, there was no yarn breakage in the preliminary carbonization furnace, and continuous operation for one hour was possible. However, the carbon fiber obtained by heating the pre-carbonized fiber to 1500°C in a nitrogen gas atmosphere has a thread diameter of 9.8 μm and a tensile strength of 3.
20GPa, tensile modulus is 320GPa, compressive strength is 0
．． It was 44 GPa.
【００８８】更に、炭素繊維をアルゴンガス雰囲気中で
２５００℃まで昇温して得た黒鉛炭素繊維は、糸径が９
．７μｍであり、引張強度は３．６ＧＰａ、引張弾性率
は３５０ＧＰａ、圧縮強度は０．４２ＧＰａであった。Furthermore, graphite carbon fiber obtained by heating carbon fiber to 2500°C in an argon gas atmosphere has a thread diameter of 9.
．． 7 μm, tensile strength was 3.6 GPa, tensile modulus was 350 GPa, and compressive strength was 0.42 GPa.
【００８９】比較例６
実施例１において、ピッチ繊維束の不融化時、不融化繊
維束の予備炭化時及び予備炭化繊維束の炭化時に延伸処
理を加えない以外は、実施例１と同様に処理した。Comparative Example 6 Processing was carried out in the same manner as in Example 1, except that no stretching treatment was applied during infusibility of the pitch fiber bundle, pre-carbonization of the infusible fiber bundle, and carbonization of the pre-carbonized fiber bundle. did.
【００９０】予備炭化繊維を窒素ガス雰囲気中で１５０
０℃まで昇温して得た炭素繊維の糸径は１０．０μｍで
あり、引張強度は２．５ＧＰａ、引張弾性率は２５０Ｇ
Ｐａ、圧縮強度は０．９５ＧＰａであった。[0090] The pre-carbonized fiber was heated to 150% in a nitrogen gas atmosphere.
The carbon fiber obtained by raising the temperature to 0°C has a thread diameter of 10.0 μm, a tensile strength of 2.5 GPa, and a tensile modulus of 250 G.
Pa, and the compressive strength was 0.95 GPa.
【００９１】更に、炭素繊維をアルゴンガス雰囲気中で
２５００℃まで昇温して得た黒鉛炭素繊維は、糸径が９
．９μｍであり、引張強度は２．９ＧＰａ、引張弾性率
は６５０ＧＰａ、圧縮強度は０．３２ＧＰａであった。Furthermore, graphite carbon fiber obtained by heating carbon fiber to 2500°C in an argon gas atmosphere has a thread diameter of 9.
．． 9 μm, tensile strength was 2.9 GPa, tensile modulus was 650 GPa, and compressive strength was 0.32 GPa.
【００９２】[0092]
【発明の効果】以上説明したように、本発明の製造方法
では、ピッチ繊維束の不融化及び不融化繊維束の予備炭
化を、それぞれの繊維束の溶融破断温度又は溶融破断温
度よりも３０〜１００℃低い温度まで１００〜５０００
℃／分の速度で昇温して、繊維束を１〜３００秒の極く
短時間の熱処理しながら同時に延伸率５〜１００％の延
伸処理することにより行ない、更に予備炭化繊維束の炭
化を延伸処理を加えながら行なうので、不融化炉内及び
予備炭化炉内での繊維束の断糸や毛羽立ちを押さえて、
不融化及び予備炭化の際の歩留りを向上するだけでなく
、繊維の引張強度、引張弾性率及び圧縮強度を著しく向
上した炭素繊維を得ることができる。As explained above, in the manufacturing method of the present invention, the pitch fiber bundle is infusible and the infusible fiber bundle is pre-carbonized at a temperature of 30 to 30°C higher than the melt breakage temperature or the melt breakage temperature of each fiber bundle. 100~5000 to 100℃ lower temperature
The temperature is raised at a rate of °C/min, and the fiber bundle is heat-treated for a very short time of 1 to 300 seconds, while at the same time stretching treatment is performed at a stretching rate of 5 to 100%, and the pre-carbonized fiber bundle is further carbonized. Since the process is carried out while adding stretching treatment, breakage and fluffing of the fiber bundles in the infusibility furnace and pre-carbonization furnace can be suppressed.
In addition to improving the yield during infusibility and preliminary carbonization, it is possible to obtain carbon fibers with significantly improved tensile strength, tensile modulus, and compressive strength of the fibers.
【００９３】又上記のような延伸処理をすることにより
高度な延伸が可能となるので、１本の糸系が４〜１０μ
ｍの細径の炭素繊維を容易に得ることができる。その結
果、複合材料にする際の糸扱い性が良好で、且つ複合材
料にしたときの引張強度、引張弾性率及び圧縮強度等の
物性を発現し易い炭素繊維を得ることができる。[0093] Also, by carrying out the above-mentioned drawing treatment, it is possible to achieve a high degree of drawing, so that one thread system can have a thickness of 4 to 10 μm.
Carbon fibers with a diameter of m can be easily obtained. As a result, it is possible to obtain carbon fibers that have good yarn handling properties when made into a composite material, and which easily exhibit physical properties such as tensile strength, tensile modulus, and compressive strength when made into a composite material.
Claims (1)
化し、前記不融化された不融化繊維束を予備炭化し、前
記予備炭化された予備炭化繊維束を炭化し、必要に応じ
て更に黒鉛化することからなるピッチ系炭素繊維及び黒
鉛繊維の製造方法において、前記ピッチ繊維束の不融化
を、酸化性ガス雰囲気中で繊維束の溶融破断温度よりも
３０〜１００℃低い温度まで１００〜５０００℃／分の
速度で昇温して、繊維束を１〜３００秒の極く短時間で
熱処理しながら延伸率５〜１００％の延伸処理をするこ
とにより行ない、前記不融化繊維束の予備炭化を、不活
性ガス雰囲気中で繊維束の溶融破断温度よりも３０〜１
００℃低い温度まで１００〜５０００℃／分の速度で昇
温して、繊維束を１〜３００秒の極く短時間で熱処理し
ながら延伸率５〜１００％の延伸処理をすることにより
行ない、更に前記予備炭化繊維束の炭化を、繊維束に延
伸率１〜３０％の延伸処理をしながら行なうことを特徴
とするピッチ系炭素繊維及び黒鉛繊維の製造方法。1. Spun and bundled pitch fiber bundles are infusible, the infusible infusible fiber bundles are pre-carbonized, the pre-carbonized pre-carbonized fiber bundles are carbonized, and if necessary, further In a method for producing pitch-based carbon fibers and graphite fibers, which comprises graphitizing, the pitch fiber bundle is made infusible by 100 to 100 degrees Celsius lower than the melting and breaking temperature of the fiber bundle in an oxidizing gas atmosphere. This is carried out by elevating the temperature at a rate of 5000°C/min, heat-treating the fiber bundle for a very short time of 1 to 300 seconds, and stretching the fiber bundle at a stretching rate of 5 to 100%, thereby preparing the infusible fiber bundle. Carbonization is carried out at a temperature of 30 to 1
The fiber bundle is heated at a rate of 100 to 5000 °C/min to a temperature as low as 00 °C, and the fiber bundle is heat-treated for a very short time of 1 to 300 seconds while being stretched at a stretching rate of 5 to 100%. A method for producing pitch-based carbon fibers and graphite fibers, further comprising carbonizing the pre-carbonized fiber bundle while subjecting the fiber bundle to a stretching treatment at a stretching rate of 1 to 30%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5931591A JPH04272234A (en) | 1991-02-28 | 1991-02-28 | Production of pitch-base carbon fiber and graphite fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5931591A JPH04272234A (en) | 1991-02-28 | 1991-02-28 | Production of pitch-base carbon fiber and graphite fiber |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH04272234A true JPH04272234A (en) | 1992-09-29 |
Family
ID=13109809
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5931591A Pending JPH04272234A (en) | 1991-02-28 | 1991-02-28 | Production of pitch-base carbon fiber and graphite fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH04272234A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018517077A (en) * | 2015-06-11 | 2018-06-28 | ストラ エンソ オーワイジェイ | Fiber and method for producing the same |
-
1991
- 1991-02-28 JP JP5931591A patent/JPH04272234A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2018517077A (en) * | 2015-06-11 | 2018-06-28 | ストラ エンソ オーワイジェイ | Fiber and method for producing the same |
| US10626523B2 (en) | 2015-06-11 | 2020-04-21 | Stora Enso Oyj | Fiber and a process for the manufacture thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2000345435A (en) | Pitch fiber bundle, pitch-based carbon fiber bundle and its production | |
| JPH0737689B2 (en) | Method for producing carbon fiber and graphite fiber | |
| JPH04272234A (en) | Production of pitch-base carbon fiber and graphite fiber | |
| JPH04272235A (en) | Production of pitch-base carbon fiber and graphite fiber | |
| JPH04272233A (en) | Production of pitch-base carbon fiber and graphite fiber | |
| JPH04272232A (en) | Production of pitch-base carbon fiber and graphite fiber | |
| JPH04257322A (en) | Production of pitch carbon fiber and graphite fiber | |
| JPH04245923A (en) | Production of pitch-based carbon fiber and graphite fiber | |
| JPS62289617A (en) | Production of carbon and graphite fiber | |
| JPH04257323A (en) | Production of pitch carbon fiber and graphite fiber | |
| JPS59223315A (en) | Production of pitch based carbon fiber | |
| JPH0491229A (en) | Production of pitch-based carbon fiber | |
| JPH04119126A (en) | Production of pitch-based carbon fiber and graphite fiber | |
| JPH05171519A (en) | Production of pitch carbon fiber | |
| JPS62133123A (en) | Production of carbon fiber and graphite fiber | |
| JPH04119125A (en) | Production of pitch-based carbon fiber and graphite fiber | |
| JPH0491228A (en) | Production of pitch-based carbon fiber | |
| JP2582848B2 (en) | Method for producing pitch-based carbon fiber | |
| JPH05171518A (en) | Pitch carbon fiber | |
| JPS62191518A (en) | Production of carbon fiber and graphite fiber | |
| JP3321913B2 (en) | Method for producing pitch-based carbon fiber | |
| JPS60126324A (en) | Method for producing carbon fiber bundle having high orientation of filament | |
| JPH05295620A (en) | Production of pitch-based carbon fiber | |
| JP2763001B2 (en) | Method for producing pitch carbon fiber | |
| JPS6278220A (en) | Production of ribbon-like carbon fiber |