JP2015203166A - Carbon fiber precursor fiber and method for producing carbon fiber precursor fiber - Google Patents
Carbon fiber precursor fiber and method for producing carbon fiber precursor fiber Download PDFInfo
- Publication number
- JP2015203166A JP2015203166A JP2014082800A JP2014082800A JP2015203166A JP 2015203166 A JP2015203166 A JP 2015203166A JP 2014082800 A JP2014082800 A JP 2014082800A JP 2014082800 A JP2014082800 A JP 2014082800A JP 2015203166 A JP2015203166 A JP 2015203166A
- Authority
- JP
- Japan
- Prior art keywords
- fiber
- carbon fiber
- stretching
- oil agent
- precursor
- 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.)
- Granted
Links
Landscapes
- Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)
- Artificial Filaments (AREA)
Abstract
Description
本発明は、ポリアクリロニトリル系炭素繊維の製造に用いられる炭素繊維前駆体繊維およびその製造方法に関する。 The present invention relates to a carbon fiber precursor fiber used for production of polyacrylonitrile-based carbon fiber and a production method thereof.
炭素繊維は航空機用途、ゴルフシャフトや釣り竿等のスポーツ用途、一般産業用の繊維強化複合材料の強化材として広く使用されている。このような炭素繊維の中でも、アクリロニトリル系繊維を耐炎化、炭素化して得られる炭素繊維は、機械的特性に優れることから、今後のますますの需要拡大が見込まれている。近年、炭素繊維の優位性が高まるにつれ、特にスポーツ、航空宇宙用途において、炭素繊維に対する高強度化、高品位化が求められている。 Carbon fiber is widely used as a reinforcing material for fiber-reinforced composite materials for aircraft use, sports use such as golf shafts and fishing rods, and general industries. Among such carbon fibers, carbon fibers obtained by making acrylonitrile fiber flame resistant and carbonized are excellent in mechanical properties, and therefore, further demand is expected to increase in the future. In recent years, as the superiority of carbon fibers increases, particularly in sports and aerospace applications, there is a demand for higher strength and higher quality for carbon fibers.
炭素繊維の製造工程において、耐炎化処理や炭化処理などの高温処理で発生する単繊維同士の融着が炭素繊維の破断を引き起こす欠陥を形成し、ひいては毛羽、糸切れの原因にもなることが、高強度、高品質な炭素繊維を製造する際の課題となっている。炭素繊維製造工程での単繊維間接着を抑制するために、耐熱性の高いシリコーン系油剤が一般的に前駆体繊維に付与されている。
しかし、前駆体繊維にシリコーン系油剤を付着させることで炭素繊維製造工程での単繊維間接着は抑制されるものの、前駆体繊維の単繊維内部に侵入したシリコーン系油剤がかえって欠陥を引き起こし、炭素繊維の強度低下や毛羽、糸切れの原因となることが新たな問題となっている。
In the production process of carbon fiber, the fusion of single fibers generated by high-temperature treatment such as flameproofing treatment and carbonization treatment can form defects that cause the carbon fiber to break, which in turn can cause fluff and yarn breakage. It has become a challenge when producing high-strength, high-quality carbon fibers. In order to suppress adhesion between single fibers in the carbon fiber manufacturing process, a silicone-based oil agent having high heat resistance is generally applied to the precursor fiber.
However, the adhesion between the single fibers in the carbon fiber production process is suppressed by attaching the silicone oil to the precursor fiber, but the silicone oil that has penetrated into the single fiber of the precursor fiber causes a defect, and carbon It becomes a new problem to cause a decrease in fiber strength, fluff and thread breakage.
この問題を解決するために、例えば特許文献１、２には、前駆体繊維の製造工程での凝固や延伸条件を調節して、繊維表面の空隙を低減させた低延伸倍率の前駆体繊維に油剤を付与することで、シリコーン系油剤の繊維内部への侵入を防ぐことが提案されている。しかしながら、低延伸倍率の前駆体繊維に油剤を付与するこれらの方法では、単繊維内部への油剤侵入を十分に防ぐことはできなかった。また、前駆体繊維製造初期に前駆体表面の空隙を低減させるため、脱溶媒が不十分となり、繊維内部欠陥が生じやすくなってしまっていた。そのため、これらの前駆体繊維を用いて得られる炭素繊維の強度や品質は、満足できるものではなかった。そのため、高強度かつ高品質な炭素繊維を与える炭素繊維前駆体繊維が求められている。 In order to solve this problem, for example, in Patent Documents 1 and 2, the low-stretch ratio precursor fiber in which voids on the fiber surface are reduced by adjusting the solidification and drawing conditions in the precursor fiber manufacturing process. It has been proposed to prevent the silicone-based oil from entering the fiber by applying the oil. However, these methods of applying an oil agent to a precursor fiber having a low draw ratio cannot sufficiently prevent the oil agent from entering the inside of a single fiber. In addition, since the voids on the surface of the precursor are reduced in the initial stage of the production of the precursor fiber, the solvent removal is insufficient and the fiber internal defect is likely to occur. Therefore, the strength and quality of the carbon fibers obtained using these precursor fibers have not been satisfactory. Therefore, a carbon fiber precursor fiber that provides high-strength and high-quality carbon fiber is required.
本発明の目的は、高強度且つ高品質な炭素繊維を製造するのに適した炭素繊維前駆体繊維を提供することにある。 An object of the present invention is to provide a carbon fiber precursor fiber suitable for producing high-strength and high-quality carbon fibers.
上記課題を解決する本発明の炭素繊維前駆体繊維は、シリコーン系油剤が付着したポリアクリロニトリル系繊維からなる炭素繊維前駆体繊維であって、繊維表面から１μｍ以上内層にＳｉ原子が存在しない炭素繊維前駆体繊維である。本発明において、油剤の付着量が０．０１〜１０．０ｗｔ％であることが好ましい。 The carbon fiber precursor fiber of the present invention that solves the above problems is a carbon fiber precursor fiber made of polyacrylonitrile fiber to which a silicone-based oil is adhered, and is a carbon fiber having no Si atoms in the inner layer of 1 μm or more from the fiber surface It is a precursor fiber. In this invention, it is preferable that the adhesion amount of an oil agent is 0.01-10.0 wt%.
本発明の炭素繊維前駆体繊維の製造方法は、アクリロニトリル系重合体を含む紡糸溶液から凝固糸を得る凝固工程、凝固糸を延伸し延伸糸を得る延伸工程、延伸糸に油剤を付与する油剤付与工程、を含む炭素繊維前駆体繊維の製造方法であって、凝固工程及び延伸工程において８倍以上延伸処理した後油剤を付与する炭素繊維前駆体繊維の製造方法である。本発明の炭素繊維の製造方法において、凝固工程および延伸工程での延伸倍率が総延伸倍率の８０％以上であることが好ましい。また、延伸工程において、気相中で１．５〜１０倍延伸する気中延伸を行うことが好ましく、気中延伸後に油剤を付与することも好ましい。 The carbon fiber precursor fiber production method of the present invention includes a coagulation step for obtaining a coagulated yarn from a spinning solution containing an acrylonitrile-based polymer, a drawing step for drawing the coagulated yarn to obtain a drawn yarn, and an oil agent for applying an oil agent to the drawn yarn. A carbon fiber precursor fiber including a step, wherein the oil agent is applied after a stretching process of 8 times or more in the coagulation step and the stretching step. In the carbon fiber production method of the present invention, the draw ratio in the solidification step and the drawing step is preferably 80% or more of the total draw ratio. Further, in the stretching step, it is preferable to perform air stretching that extends 1.5 to 10 times in the gas phase, and it is also preferable to apply an oil agent after air stretching.
本発明の炭素繊維前駆体繊維によれば、高強度且つ高品質な炭素繊維を製造することができる。
本発明の炭素繊維前駆体繊維の製造方法によれば、繊維内部への油剤浸透を抑制することができ、また紡糸工程における糸切れや毛羽発生を抑えることもできるため、高強度かつ高品質な炭素繊維を製造するのに適した炭素繊維前駆体繊維を得ることができる。
According to the carbon fiber precursor fiber of the present invention, a high-strength and high-quality carbon fiber can be produced.
According to the method for producing a carbon fiber precursor fiber of the present invention, oil agent permeation into the fiber can be suppressed, and yarn breakage and fluff generation in the spinning process can be suppressed. A carbon fiber precursor fiber suitable for producing carbon fiber can be obtained.
本発明の炭素繊維前駆体繊維は、シリコーン系油剤が付着したポリアクリロニトリル系繊維からなる炭素繊維前駆体繊維であって、繊維表面から１μｍ以上内層にＳｉ原子が存在しない炭素繊維前駆体繊維である。
本発明において、Ｓｉ原子が存在しないとは、走査透過顕微鏡（ＳＴＥＭ）を用いたエネルギー分散型Ｘ線分光分析（ＥＤＳ分析）によってＳｉ原子が検出されない場合をいう。ＥＤＳ分析によるＳｉ原子の検出下限は一般的に１ｗｔ％である。繊維表面から１μｍ以上内層にＳｉ原子が存在しない炭素繊維前駆体とすることで、シリコーン油剤が付着した炭素繊維前駆体繊維であるにもかかわらず、炭素繊維製造工程においてシリコーン系油剤に起因する欠陥の生成が起こりにくく、高強度且つ高品質な炭素繊維を製造することができる。
The carbon fiber precursor fiber of the present invention is a carbon fiber precursor fiber made of polyacrylonitrile fiber to which a silicone-based oil is adhered, and is a carbon fiber precursor fiber having no Si atom in the inner layer of 1 μm or more from the fiber surface. .
In the present invention, the absence of Si atoms refers to the case where Si atoms are not detected by energy dispersive X-ray spectroscopy (EDS analysis) using a scanning transmission microscope (STEM). The lower limit of detection of Si atoms by EDS analysis is generally 1 wt%. A defect caused by a silicone-based oil in the carbon fiber manufacturing process, even though it is a carbon fiber precursor fiber with a silicone oil adhering to it by using a carbon fiber precursor in which Si atoms do not exist in the inner layer of 1 μm or more from the fiber surface Can be produced, and high-strength and high-quality carbon fibers can be produced.
本発明において、油剤の付着量は０．０１〜１０．０ｗｔ％であることが好ましく、０．１〜５．０ｗｔ％であることがより好ましく、０．２〜１．０ｗｔ％であることが特に好ましい。油剤付着量をこの範囲に制御することで、紡糸工程及びその後の耐炎化工程での糸切れ、毛羽の発生を抑制し、高品質の炭素繊維前駆体繊維および炭素繊維を得ることができる。油剤の付着量が少ないと、繊維表面に十分に油剤が付着しないため、紡糸工程及びその後の耐炎化工程での糸切れ、毛羽の発生が多くなりやすい傾向があり、一方、油剤の付着量が多すぎると、紡糸工程や耐炎化工程の繊維搬送ローラーやガイドなどの表面に堆積して、繊維が巻付いて断糸の要因になるといった問題が発生しやすくなる傾向がある。 In this invention, it is preferable that the adhesion amount of an oil agent is 0.01-10.0 wt%, It is more preferable that it is 0.1-5.0 wt%, It is 0.2-1.0 wt% Particularly preferred. By controlling the oil agent adhesion amount within this range, it is possible to suppress yarn breakage and fluff generation in the spinning process and the subsequent flame resistance process, and to obtain high-quality carbon fiber precursor fibers and carbon fibers. If the amount of the oil agent is small, the oil agent does not sufficiently adhere to the fiber surface, so that there is a tendency that yarn breakage and fluff are likely to occur in the spinning process and the subsequent flameproofing process. If the amount is too large, there is a tendency that problems such as accumulation on the surface of the fiber conveyance roller or guide in the spinning process or flameproofing process, and the cause of the fiber winding and causing yarn breakage tend to occur.
前駆体繊維のフィラメント数は、製造効率の面では１００〜１０００００本が好ましく、１０００〜８００００本がより好ましく、３０００〜５００００本が特に好ましい。
また、前駆体繊維の単繊維繊度は、得られる炭素繊維の強度の観点から、０．８〜２．０ｄｔｅｘであることが好ましく、１．０〜１．５ｄｔｅｘであることがよりに好ましい。前駆体繊維の単繊維直径は８〜２０μｍであることが好ましく、１０〜１５μｍであることがより好ましい。
上記のような本発明の炭素繊維前駆体繊維は、炭素繊維製造工程での欠陥生成や毛羽や糸切れなどを抑制することができるため、本発明の炭素繊維前駆体繊維を炭素繊維の製造に用いた場合、高強度且つ高品質な炭素繊維を製造することができる。
In terms of production efficiency, the number of filaments of the precursor fiber is preferably 100 to 100,000, more preferably 1000 to 80000, and particularly preferably 3000 to 50000.
In addition, the single fiber fineness of the precursor fiber is preferably 0.8 to 2.0 dtex, and more preferably 1.0 to 1.5 dtex, from the viewpoint of the strength of the obtained carbon fiber. The single fiber diameter of the precursor fiber is preferably 8 to 20 μm, and more preferably 10 to 15 μm.
Since the carbon fiber precursor fiber of the present invention as described above can suppress generation of defects, fluff, yarn breakage, etc. in the carbon fiber production process, the carbon fiber precursor fiber of the present invention is used for the production of carbon fiber. When used, high-strength and high-quality carbon fibers can be produced.
本発明のもうひとつの態様である炭素繊維前駆体繊維の製造方法は、アクリロニトリル系重合体を含む紡糸溶液から凝固糸を得る凝固工程、凝固糸を延伸し延伸糸を得る延伸工程、延伸糸に油剤を付与する油剤付与工程、を含む炭素繊維前駆体繊維の製造方法であって、凝固工程及び延伸工程において８倍以上延伸処理した後油剤を付与する炭素繊維前駆体繊維の製造方法である。凝固工程及び延伸工程において油剤を付与することなく高い延伸倍率で延伸処理を行うことで、繊維の緻密性が高まり、繊維内の空隙が減少する。そのような高い倍率で延伸処理された緻密な延伸糸とした後初めて油剤を付与することで、繊維内部までの油剤の浸透を抑制することができる。 The carbon fiber precursor fiber manufacturing method according to another aspect of the present invention includes a coagulation step of obtaining a coagulated yarn from a spinning solution containing an acrylonitrile polymer, a drawing step of drawing the coagulated yarn to obtain a drawn yarn, and a drawn yarn. It is a manufacturing method of the carbon fiber precursor fiber which includes the oil agent provision process which provides an oil agent, Comprising: It is a manufacturing method of the carbon fiber precursor fiber which provides an oil agent after extending | stretching 8 times or more in a coagulation process and an extending process. By performing the stretching treatment at a high stretching ratio without applying an oil agent in the coagulation step and the stretching step, the denseness of the fibers increases and the voids in the fibers decrease. By applying an oil agent for the first time after forming a dense drawn yarn drawn at such a high magnification, it is possible to suppress the penetration of the oil agent into the fiber.
通常、油剤付与前の凝固糸は、緻密化処理がされていないため、内部のボイドが多く、４倍を超える高い延伸倍率で延伸を行うと糸切れが発生し、毛羽の多い低品質な炭素繊維前駆体になってしまう。しかし、本発明者らは鋭意検討の結果、油剤付与前の凝固糸に対して、８倍以上のさらに高い延伸倍率の延伸処理を行うことで、意外なことにかえって毛羽の発生が抑制される上に、繊維の緻密性が高まり、油剤付与時に繊維内部への油剤の浸透を抑制できることを見出した。
本発明において凝固工程及び延伸工程の延伸処理倍率は、８倍以上であり、８〜３０倍であることが好ましく、１０〜２０倍であることが更に好ましく、１２〜１８倍であることが特に好ましい。
Usually, the solidified yarn before oil application is not densified, so there are many voids inside, and if it is stretched at a high draw ratio exceeding 4 times, yarn breakage occurs and low quality carbon with many fluff It becomes a fiber precursor. However, as a result of intensive studies, the present inventors unexpectedly suppress the occurrence of fluff by performing a drawing process at a higher draw ratio of 8 times or more on the coagulated yarn before applying the oil agent. Further, the present inventors have found that the denseness of the fibers is increased, and that the oil agent can be prevented from penetrating into the fiber when the oil agent is applied.
In the present invention, the stretching treatment ratio in the coagulation step and the stretching step is 8 times or more, preferably 8 to 30 times, more preferably 10 to 20 times, and particularly preferably 12 to 18 times. preferable.
本発明において、油剤付与工程の前の、凝固工程および延伸工程での延伸倍率が総延伸倍率の８０％以上であることが好ましい。油剤付与前の凝固工程および延伸工程での延伸倍率を総延伸倍率の８０％以上とすることで、得られる前駆体繊維の欠陥生成が抑制され、強度が高く、毛羽の少ない、高強度かつ高品質の炭素繊維がより得られやすくなる。本発明において、凝固工程および延伸工程での延伸倍率は総延伸倍率の８５〜１００％であることがより好ましく、９０〜９８％であることがさらに好ましい。本発明において総延伸倍率は、高強度かつ高品質の炭素繊維を得るという観点から、８〜３０倍であることが好ましく、１０〜２５倍であることがより好ましく１２〜２０倍であることが特に好ましい。 In this invention, it is preferable that the draw ratio in a coagulation process and an extending process before an oil agent provision process is 80% or more of a total draw ratio. By setting the draw ratio in the coagulation step and the draw step before applying the oil to 80% or more of the total draw ratio, generation of defects in the obtained precursor fiber is suppressed, the strength is high, the fluff is low, the high strength and the high It becomes easier to obtain quality carbon fiber. In the present invention, the draw ratio in the coagulation step and the draw step is more preferably 85 to 100% of the total draw ratio, and further preferably 90 to 98%. In the present invention, the total draw ratio is preferably 8 to 30 times, more preferably 10 to 25 times, and more preferably 12 to 20 times, from the viewpoint of obtaining high-strength and high-quality carbon fibers. Particularly preferred.
また、本発明で行う延伸工程として、例えば、水または溶媒を含む液中で延伸する湿潤延伸処理、加圧水蒸気等の気相中で延伸する気中延伸処理、熱ローラー等の加熱体を用いる熱延伸処理などの公知の延伸手段を用いて凝固糸を延伸することができる。中でも、液中で延伸する湿潤延伸処理、気相中で延伸する気中延伸処理が、凝固糸を乾燥させることなく延伸処理できるため好ましい。本発明においては、凝固糸を膨潤状態に保って延伸処理を行うことが好ましい。凝固糸を膨潤状態に保って延伸処理を行うことで、欠陥の生成や糸切れ、毛羽を抑え、延伸処理を行うことができる。さらに、本発明においては、油剤付与工程前の延伸工程において、気相中で１．５〜１０倍延伸する気中延伸を行うことが好ましい。気中延伸処理を用いると、緻密化されていない油剤付与前の凝固糸であっても、欠陥の生成や糸切れ、毛羽を抑え、かつ高い延伸倍率まで延伸処理を行うことができる。 気中延伸処理での延伸倍率は１．５〜１０倍であることが好ましく、より好ましくは、１．８〜５倍、更に好ましくは、２．０〜３．０倍である。 In addition, as the stretching step performed in the present invention, for example, a wet stretching process for stretching in a liquid containing water or a solvent, an in-air stretching process for stretching in a gas phase such as pressurized steam, and heat using a heating body such as a heat roller. The coagulated yarn can be drawn using a known drawing means such as a drawing process. Among these, a wet stretching process for stretching in a liquid and an air stretching process for stretching in a gas phase are preferable because the stretching process can be performed without drying the coagulated yarn. In the present invention, it is preferable to perform the stretching treatment while keeping the coagulated yarn in a swollen state. By performing the stretching process while keeping the coagulated yarn in a swollen state, the generation of defects, yarn breakage, and fluff can be suppressed, and the stretching process can be performed. Furthermore, in this invention, it is preferable to perform the air | atmosphere extending | stretching extended | stretched 1.5 to 10 times in a gaseous phase in the extending | stretching process before an oil agent provision process. When the air-drawing treatment is used, even if the solidified yarn is not densified and before the oil agent is applied, the formation of defects, yarn breakage, and fluff can be suppressed, and the drawing treatment can be performed up to a high draw ratio. The draw ratio in the air drawing treatment is preferably 1.5 to 10 times, more preferably 1.8 to 5 times, and still more preferably 2.0 to 3.0 times.
気中延伸処理に用いる気相としては、特に制限はないが、加圧水蒸気や加熱空気などが好ましく用いられる。中でも、加圧水蒸気が、凝固糸を膨潤状態に保って延伸処理できるため好ましい。気中延伸処理に用いる気体の圧力は０．０５〜１．０ＭＰａであることが好ましく、０．０６〜０．５ＭＰａであることがより好ましく、０．０８〜０．３ＭＰａであることが特に好ましい。気中延伸処理の温度は、１０５〜１４０℃が好ましく、１１０〜１３０℃がより好ましい。 The gas phase used for the air stretching treatment is not particularly limited, but pressurized steam, heated air, and the like are preferably used. Among these, pressurized steam is preferable because the coagulated yarn can be stretched while being kept in a swollen state. The pressure of the gas used for the air stretching treatment is preferably 0.05 to 1.0 MPa, more preferably 0.06 to 0.5 MPa, and particularly preferably 0.08 to 0.3 MPa. . The temperature in the air stretching treatment is preferably 105 to 140 ° C, more preferably 110 to 130 ° C.
また、延伸工程における延伸処理は、気中延伸処理と湿潤延伸処理を組み合わせて行うことが、より高い倍率まで延伸処理を行うことができるため、好ましい。気中延伸処理と湿潤延伸処理を組み合わせて行う場合、気中延伸処理の延伸倍率は、１．５〜５倍であることが好ましく、湿潤延伸処理の延伸倍率は、３〜１５倍であることが好ましく、５〜１０倍であることがより好ましい。また、気中延伸処理と湿潤延伸処理の延伸倍率の比が、１：２〜１：５であることが好ましい。気中延伸処理と湿潤延伸処理を組み合わせて行う場合、湿潤延伸処理を先に行うことが好ましい。 Moreover, since the extending | stretching process in an extending | stretching process can perform an extending | stretching process to a higher magnification, it is preferable to perform in-air extending | stretching process and wet extending | stretching process combining. When performing the air stretching treatment and the wet stretching treatment in combination, the stretching ratio of the air stretching process is preferably 1.5 to 5 times, and the stretching ratio of the wet stretching process is 3 to 15 times. Is preferable, and 5 to 10 times is more preferable. Moreover, it is preferable that ratio of the draw ratio of an air extending | stretching process and a wet extending | stretching process is 1: 2 to 1: 5. In the case where the air stretching treatment and the wet stretching treatment are performed in combination, the wet stretching treatment is preferably performed first.
本発明においては、気中延伸後に油剤を付与することが、繊維内部までの油剤の浸透を抑制しやすいため好ましい。
また、本発明においては、油剤付与後に、後延伸処理を行うこともできる。後延伸工程での延伸処理としては、例えば、水または溶媒を含む液中で延伸する湿潤延伸処理、加圧水蒸気等の気相中で延伸する気中延伸処理、熱ローラー等の加熱体を用いる熱延伸処理などの公知の延伸手段を用いて凝固糸を延伸することができるが、気中延伸処理または熱延伸処理により延伸することが好ましい。後延伸処理での延伸倍率は、１．０〜１．５倍であることが好ましく、１．０１〜１．２５倍であることがより好ましい。
In the present invention, it is preferable to apply an oil agent after stretching in the air because it is easy to suppress the penetration of the oil agent into the fiber.
In the present invention, post-stretching treatment can also be performed after applying the oil. Examples of the stretching process in the post-stretching process include a wet stretching process for stretching in a liquid containing water or a solvent, an air stretching process for stretching in a gas phase such as pressurized steam, and heat using a heating body such as a heat roller. The coagulated yarn can be drawn using a known drawing means such as a drawing treatment, but is preferably drawn by an air drawing treatment or a heat drawing treatment. The draw ratio in the post-drawing treatment is preferably 1.0 to 1.5 times, and more preferably 1.01 to 1.25 times.
上記のような本発明の製造方法を用いると、繊維内部への油剤浸透を抑制することができ、また紡糸工程における糸切れや毛羽発生を抑えることもできるため、高強度かつ高品質な炭素繊維を製造するのに適した炭素繊維前駆体繊維を得ることができる。
以下に本発明の炭素繊維前駆体繊維の製造方法についてより詳細に説明する。
When the production method of the present invention as described above is used, oil agent penetration into the fiber can be suppressed, and yarn breakage and fluff generation in the spinning process can also be suppressed. Therefore, high strength and high quality carbon fiber The carbon fiber precursor fiber suitable for manufacturing can be obtained.
Below, it demonstrates in detail about the manufacturing method of the carbon fiber precursor fiber of this invention.
（紡糸溶液調整工程）
本発明において用いられる紡糸溶液としては、アクリロニトリル系重合体を含む紡糸溶液であれば、従来公知のものが何ら制限無く使用できる。本発明に用いるポリアクリロニトリル系重合体は、アクリロニトリルを好ましくは９０質量％以上、より好ましくは９５〜９９質量％含有する単量体を単独又は共重合した重合体である。本発明で用いるポリアクリロニトリル系重合体の組成としては、アクリロニトリル単量体９０〜９９質量％、及びビニル骨格を有するアクリロニトリルと共重合可能なコモノマー１〜１０質量％含有する共重合体であることが好ましい。アクリロニトリルと共重合可能なコモノマーとしては、例えばアクリル酸、イタコン酸等の酸類及びその塩類、アクリル酸メチル、アクリル酸エチルといったアクリル酸エステル類、アクリルアミドといったアミド類等が挙げられ、目的とする繊維特性に応じて１つまたは２以上を組み合わせて使用することができる。中でも、アクリル酸メチルとイタコン酸を組み合わせて使用することが好ましい。
(Spinning solution adjustment process)
As the spinning solution used in the present invention, any conventionally known spinning solution can be used without any limitation as long as it is a spinning solution containing an acrylonitrile-based polymer. The polyacrylonitrile-based polymer used in the present invention is a polymer obtained by homopolymerizing or copolymerizing a monomer containing acrylonitrile, preferably 90% by mass or more, more preferably 95-99% by mass. The composition of the polyacrylonitrile-based polymer used in the present invention is a copolymer containing 90 to 99% by mass of an acrylonitrile monomer and 1 to 10% by mass of a comonomer copolymerizable with acrylonitrile having a vinyl skeleton. preferable. Examples of the comonomer copolymerizable with acrylonitrile include acids such as acrylic acid and itaconic acid and salts thereof, acrylic acid esters such as methyl acrylate and ethyl acrylate, amides such as acrylamide, etc. Depending on, one or a combination of two or more can be used. Among these, it is preferable to use methyl acrylate and itaconic acid in combination.
ポリアクリロニトリル系重合体の重合方法は、溶液重合、懸濁重合等公知の方法の何れも採用することができる。重合反応に用いる重合触媒としては、重合方法に応じて、適宜公知の触媒を用いることができ、たとえば、アゾ化合物や過酸化物などのラジカル重合触媒やレドックス触媒などを用いることができる。レドックス触媒を用いる場合は、例えば還元剤としては亜硫酸水素ナトリウム、亜硫酸水素アンモニウム、アルキルメルカプタン類、亜硫酸水素ナトリウム、亜硫酸水素アンモニウム、酸化剤としては過硫酸カリウム、過硫酸ナトリウム、過硫酸アンモニウム、亜塩素酸ナトリウム、過硫酸アンモニウムを挙げることができる。 As a polymerization method for the polyacrylonitrile-based polymer, any of known methods such as solution polymerization and suspension polymerization can be employed. As the polymerization catalyst used in the polymerization reaction, a known catalyst can be used as appropriate depending on the polymerization method. For example, a radical polymerization catalyst such as an azo compound or a peroxide, a redox catalyst, or the like can be used. When using a redox catalyst, for example, sodium bisulfite, ammonium bisulfite, alkyl mercaptans, sodium bisulfite, ammonium bisulfite as reducing agents, potassium persulfate, sodium persulfate, ammonium persulfate, chlorite as oxidizing agents Examples thereof include sodium and ammonium persulfate.
紡糸溶液に用いる溶剤としては、公知の溶剤を用いることができ、例えば塩化亜鉛、チオシアン酸ナトリウム等の無機化合物の水溶液や、ジメチルアセトアミド、ジメチルスルホキシド、ジメチルホルムアミド等の有機溶剤が挙げられる。中でも、溶液連続重合により工程の簡素化が可能で、かつ、重合速度が速く均質なポリマーが得られやすく、さらに、価格が安価で大量生産に向いている無機化合物の水溶液を用いることが好ましく、塩化亜鉛水溶液を用いることが特に好ましい。 As the solvent used in the spinning solution, a known solvent can be used, and examples thereof include an aqueous solution of an inorganic compound such as zinc chloride and sodium thiocyanate, and an organic solvent such as dimethylacetamide, dimethylsulfoxide, and dimethylformamide. Among them, it is possible to simplify the process by solution continuous polymerization, and it is easy to obtain a homogeneous polymer with a high polymerization rate, and it is preferable to use an aqueous solution of an inorganic compound that is inexpensive and suitable for mass production. It is particularly preferable to use an aqueous zinc chloride solution.
紡糸溶液を調整する際は、アクリロニトリル系重合体濃度は特に限定されるものではないが、５〜４０質量％と成るように溶剤の量を調節することが好ましく、６〜３０質量％とすることがより好ましく、７〜２５質量％とすることが特に好ましい。５〜４０質量％とすることで、紡糸しやすく、繊維内部が緻密な凝固糸を得やすい紡糸原液とすることができる。重合体濃度が高いほど、紡糸工程で得られる凝固糸の繊維内部の緻密性が向上するため、高強度の炭素繊維を与える前駆体繊維を得やすい。重合体濃度が高くなりすぎると、紡糸原液の粘度が高くなり紡糸安定性が低下しやすい傾向がある。 When adjusting the spinning solution, the concentration of the acrylonitrile polymer is not particularly limited, but the amount of the solvent is preferably adjusted to 5 to 40% by mass, and 6 to 30% by mass. Is more preferable, and 7 to 25% by mass is particularly preferable. By adjusting the content to 5 to 40% by mass, it is possible to obtain a spinning dope that is easy to spin and easily obtain a coagulated yarn with a dense fiber interior. As the polymer concentration is higher, the denseness inside the fiber of the coagulated yarn obtained in the spinning process is improved, so that it is easier to obtain a precursor fiber that gives a high-strength carbon fiber. If the polymer concentration is too high, the viscosity of the spinning dope tends to increase and the spinning stability tends to decrease.
（紡糸工程）
上記で得られた紡糸原液を、公知の紡糸方法を用いて、紡糸口金から紡出し凝固させることで凝固糸を得ることができる。紡糸方法としては、特に制限は無く、用いた溶剤の種類などに応じて、気相中で紡糸原液を凝固させる乾式紡糸法、凝固液中で紡糸原液を凝固させる湿式紡糸法などを用いて行うことができる。本発明においては、湿式紡糸法を用いることが好ましい。湿式紡糸法としては、紡糸口金を凝固浴中へ浸漬して、吐出される原液を凝固する湿式紡糸法と、紡糸口金を凝固浴液面から上方に設置して、吐出された原液を一旦紡糸口金と凝固液液面の間にある気相中を通過させてから凝固液の中に導入し凝固を進める乾湿式紡糸法があり、いずれの方法にも適用可能であるが、紡糸口金を凝固浴中へ浸漬して、吐出される原液を凝固する湿式紡糸法がより好ましい。
(Spinning process)
The spinning dope obtained above can be spun from a spinneret using a known spinning method and solidified to obtain a coagulated yarn. The spinning method is not particularly limited, and is performed using a dry spinning method in which the spinning stock solution is coagulated in the gas phase or a wet spinning method in which the spinning stock solution is coagulated in the coagulating solution, depending on the type of solvent used. be able to. In the present invention, it is preferable to use a wet spinning method. The wet spinning method includes a wet spinning method in which the spinneret is immersed in a coagulation bath to solidify the discharged stock solution, and the spinneret is placed above the coagulation bath liquid surface, and the discharged stock solution is once spun. There is a dry-wet spinning method that passes through the gas phase between the die and the coagulating liquid level and then introduces it into the coagulating liquid to advance the coagulation, which can be applied to either method. A wet spinning method in which the stock solution to be discharged is solidified by being immersed in a bath is more preferable.
湿式紡糸法を用いる場合、凝固液としては、水にポリアクリロニトリルを溶解できる溶剤が溶解した水溶液を用いることが好ましい。凝固液中に含まれる溶剤としては、先述の紡糸溶剤に用いる溶剤として挙げられた溶剤を用いることができるが、使用する紡糸溶液の溶媒として用いた溶剤と同じであることが好ましい。凝固浴の溶剤濃度及び温度は特に限定されるものではないが、凝固性や紡糸安定性の点から濃度は１０〜９０質量％、温度は２０〜６０℃であることが好ましい。 When the wet spinning method is used, it is preferable to use an aqueous solution in which a solvent capable of dissolving polyacrylonitrile is dissolved in water. As the solvent contained in the coagulation liquid, the solvents mentioned as the solvent used in the above spinning solvent can be used, but the same solvent as the solvent used in the spinning solution to be used is preferable. The solvent concentration and temperature of the coagulation bath are not particularly limited, but the concentration is preferably 10 to 90% by mass and the temperature is preferably 20 to 60 ° C. from the viewpoints of coagulation property and spinning stability.
紡糸原液を押し出すための紡糸口金は、１００〜１０００００の吐出孔を備えることが好ましく、１０００〜８０００の吐出孔を備えることがより好ましく、３０００〜５００００の吐出孔を備えることが特に好ましい。該吐出孔の孔径は０．０２〜０．５ｍｍであることが好ましい。孔径が０．０２ｍｍ以上であれば、吐出された糸同士の接着が起こりにくいので、均質性に優れた前駆体繊維を得やすい。孔径が０．５ｍｍ以下であれば、紡糸糸切れの発生を抑制し、紡糸安定性を維持しやすい。 The spinneret for extruding the spinning dope is preferably provided with 100 to 100,000 discharge holes, more preferably 1000 to 8000 discharge holes, and particularly preferably 3000 to 50000 discharge holes. The diameter of the discharge hole is preferably 0.02 to 0.5 mm. If the hole diameter is 0.02 mm or more, since the discharged yarns hardly adhere to each other, it is easy to obtain a precursor fiber excellent in homogeneity. If the hole diameter is 0.5 mm or less, the occurrence of spun yarn breakage is suppressed and the spinning stability is easily maintained.
（延伸工程）
上記方法で得られた凝固糸は、次いで上述の方法により、８倍以上に延伸処理（前延伸処理）され延伸糸となる。延伸工程における延伸倍率は、８〜３０倍であることが好ましく、１０〜２０倍であることが更に好ましく、１２〜１８倍であることが特に好ましい。
延伸工程では、例えば、水または溶媒を含む液中で延伸する湿潤延伸処理、加圧水蒸気等の気相中で延伸する気中延伸処理、熱ローラー等の加熱体を用いる熱延伸処理などの公知の延伸手段を用いて凝固糸を延伸することができる。本発明において、かかる延伸処理は気中延伸処理であることが好ましく、気中延伸処理と湿潤延伸処理を組み合わせて行うことがより好ましい。気中延伸処理と湿潤延伸処理を組み合わせて行う場合、湿潤延伸処理を先に行うことが好ましい。
(Stretching process)
The coagulated yarn obtained by the above method is then stretched (pre-stretched) 8 times or more by the above-described method to become a stretched yarn. The draw ratio in the drawing step is preferably 8 to 30 times, more preferably 10 to 20 times, and particularly preferably 12 to 18 times.
In the stretching process, for example, a wet stretching process that stretches in a liquid containing water or a solvent, an air stretching process that stretches in a gas phase such as pressurized steam, a thermal stretching process that uses a heating body such as a heat roller, and the like are known. The coagulated yarn can be drawn using a drawing means. In this invention, it is preferable that this extending | stretching process is an air extending | stretching process, and it is more preferable to carry out combining an air extending | stretching process and a wet extending | stretching process. In the case where the air stretching treatment and the wet stretching treatment are performed in combination, the wet stretching treatment is preferably performed first.
気中延伸処理での延伸倍率は１．５〜１０倍であることが好ましく、より好ましくは、１．８〜５倍、更に好ましくは、２．０〜３．０倍である。 気中延伸処理に用いる気相としては、加圧水蒸気または加熱空気が好ましく、加圧水蒸気が、より好ましい。気中延伸処理に用いる気体の圧力は０．０５〜１．０ＭＰａであることが好ましく、０．０６〜０．５ＭＰａであることがより好ましく、０．０８〜０．３ＭＰａであることが特に好ましい。気中延伸処理の温度は、１０５〜１４０℃が好ましく、１１０〜１３０℃がより好ましい。 The draw ratio in the air drawing treatment is preferably 1.5 to 10 times, more preferably 1.8 to 5 times, and still more preferably 2.0 to 3.0 times. As the gas phase used for the stretching process in the air, pressurized steam or heated air is preferable, and pressurized steam is more preferable. The pressure of the gas used for the air stretching treatment is preferably 0.05 to 1.0 MPa, more preferably 0.06 to 0.5 MPa, and particularly preferably 0.08 to 0.3 MPa. . The temperature in the air stretching treatment is preferably 105 to 140 ° C, more preferably 110 to 130 ° C.
また、気中延伸処理と湿潤延伸処理を組み合わせて行う場合、気中延伸処理の延伸倍率は、１．５〜５倍であることが好ましく、湿潤延伸処理の延伸倍率は、３〜１５倍であることが好ましく、５〜１０倍であることがより好ましい。また、気中延伸処理と湿潤延伸処理の延伸倍率の比が、１：２〜１：５であることが好ましい。気中延伸処理と湿潤延伸処理を組み合わせて行う場合、湿潤延伸処理を先に行うことが好ましい。 Moreover, when performing in-air extending | stretching process and wet extending | stretching process combining, it is preferable that the draw ratio of an in-air extending | stretching process is 1.5-5 times, and the draw ratio of a wet extending | stretching process is 3-15 times. It is preferable that the ratio is 5 to 10 times. Moreover, it is preferable that ratio of the draw ratio of an air extending | stretching process and a wet extending | stretching process is 1: 2 to 1: 5. In the case where the air stretching treatment and the wet stretching treatment are performed in combination, the wet stretching treatment is preferably performed first.
本発明において、前延伸処理での延伸倍率が総延伸倍率の８０％以上であることが好ましく、８５〜１００％であることがより好ましく、９０〜９８％であることがさらに好ましい。
延伸処理を行う前に、凝固糸中に残存している溶剤を低減させるため凝固糸を水洗する水洗処理を行うことが好ましい。湿潤延伸処理を行う場合、水洗処理と湿潤延伸処理を同時に行うこともできる。水洗処理を行う場合、水洗浴の温度は４０〜９８℃であることが好ましい。
In the present invention, the stretching ratio in the pre-stretching treatment is preferably 80% or more of the total stretching ratio, more preferably 85 to 100%, and still more preferably 90 to 98%.
Prior to the drawing treatment, it is preferable to carry out a water washing treatment for washing the coagulated yarn with water in order to reduce the solvent remaining in the coagulated yarn. When performing the wet stretching process, the water washing process and the wet stretching process can be performed simultaneously. When performing a water-washing process, it is preferable that the temperature of a water-washing bath is 40-98 degreeC.
（油剤付与工程）
上記方法で得られた延伸糸は、次いで、油剤付与工程で油剤が付与され炭素繊維前駆体繊維が得られる。本発明において、油剤を付与する方法は特に限定はされないが、油剤を含有する水溶液中に糸条を浸漬させて、繊維表面と油剤とを接触させる。油剤の種類は、単繊維間の接着、耐熱性、離形性、工程通過性の点からシリコーン系油剤を主成分とすることが好ましい。
(Oil agent application process)
The drawn yarn obtained by the above method is then applied with an oil agent in an oil agent application step to obtain a carbon fiber precursor fiber. In the present invention, the method of applying the oil agent is not particularly limited, but the yarn is immersed in an aqueous solution containing the oil agent to bring the fiber surface into contact with the oil agent. The type of oil is preferably composed mainly of a silicone-based oil from the viewpoint of adhesion between single fibers, heat resistance, releasability, and process passability.
本発明で用いるシリコーン系油剤としてはアミノ変性シリコーン、エポキシ変性シリコーン、エーテル変性シリコーンが好ましく、これらのうち２種以上を混合しても良い。
油剤付与工程で用いる油剤浴の油剤濃度は２．０〜１０．０％であることが好ましい。油剤浴の温度は０〜４０℃であることが好ましい。
油剤付与工程において、油剤が付与された延伸糸は、１００〜２００℃で乾燥・緻密化処理を行うことが好ましい。乾燥・緻密化処理においては、糸条を表面温度１００〜２００℃の熱ローラーを使用して加熱することが好ましい。
The silicone-based oil used in the present invention is preferably amino-modified silicone, epoxy-modified silicone, or ether-modified silicone, and two or more of these may be mixed.
The oil agent concentration of the oil agent bath used in the oil agent application step is preferably 2.0 to 10.0%. The temperature of the oil agent bath is preferably 0 to 40 ° C.
In the oil agent application step, the drawn yarn to which the oil agent has been applied is preferably dried and densified at 100 to 200 ° C. In the drying / densification treatment, the yarn is preferably heated using a hot roller having a surface temperature of 100 to 200 ° C.
（後延伸工程）
油剤が付与された炭素繊維前駆体繊維に対して、さらなる延伸処理（後延伸処理）を行ってもよい。後延伸処理での延伸倍率は１．０〜１．２５倍であることが好ましい。延伸倍率がこの範囲であると、毛羽や糸切れを抑制しながら、前駆体繊維の配向を高めることができるため、高強度の炭素繊維を得やすくなる。延伸倍率が高くなりすぎると場合は糸切れや毛羽が増加し、工程通過性の低下や炭素繊維前駆体の品質低下が起こりやすい傾向がある。
(Post-stretching process)
You may perform the further extending | stretching process (post-stretching process) with respect to the carbon fiber precursor fiber to which the oil agent was provided. The draw ratio in the post-drawing treatment is preferably 1.0 to 1.25 times. When the draw ratio is within this range, the orientation of the precursor fiber can be increased while suppressing fuzz and yarn breakage, and thus it becomes easy to obtain high-strength carbon fibers. When the draw ratio becomes too high, yarn breakage and fluff increase, and the process passability and the quality of the carbon fiber precursor tend to decrease.
本発明において上記炭素繊維前駆体繊維の製造工程における総延伸倍率は、高強度かつ高品質の炭素繊維を得るという観点から、８〜３０倍であることが好ましく、１０〜２５倍であることがより好ましく１５〜２０倍であることが特に好ましい。
上記のような本発明の製造方法を用いると、繊維内部への油剤浸透を抑制することができ、また紡糸工程における糸切れや毛羽発生を抑えることもできるため、高強度かつ高品質な炭素繊維を製造するのに適した本発明の炭素繊維前駆体繊維を得ることができる。
上記のような方法で得られる本発明の炭素繊維前駆体繊維は、炭素繊維製造工程での欠陥生成や毛羽や糸切れなどを抑制することができるため、本発明の炭素繊維前駆体繊維を耐炎化・炭素化処理することで、高強度且つ高品質な炭素繊維を製造することができる。
In the present invention, the total draw ratio in the production process of the carbon fiber precursor fiber is preferably 8 to 30 times, and preferably 10 to 25 times, from the viewpoint of obtaining high-strength and high-quality carbon fibers. More preferably 15 to 20 times.
When the production method of the present invention as described above is used, oil agent penetration into the fiber can be suppressed, and yarn breakage and fluff generation in the spinning process can also be suppressed. Therefore, high strength and high quality carbon fiber The carbon fiber precursor fiber of the present invention suitable for producing can be obtained.
The carbon fiber precursor fiber of the present invention obtained by the method as described above can suppress the generation of defects, fluff, yarn breakage, etc. in the carbon fiber production process, so that the carbon fiber precursor fiber of the present invention is flame resistant. High-strength and high-quality carbon fiber can be produced by the carbonization / carbonization treatment.
本発明の炭素繊維前駆体繊維を耐炎化処理する場合、加熱空気中、２００〜３００℃で耐炎化処理し、耐炎化繊維とすることが好ましい。耐炎化繊維は、次いで、窒素雰囲気下で３００〜８００℃で炭素化（予備炭素化）処理をし、さらにより炭素化を進めかつグラファイト化（炭素の高結晶化）を進める為に、窒素等の不活性ガス雰囲気下、好ましくは８００〜２５００℃、より好ましくは１２００〜２１００℃で炭素化することが好ましい。 When subjecting the carbon fiber precursor fiber of the present invention to flameproofing treatment, it is preferable to flameproof the heated fiber at 200 to 300 ° C. to obtain flameproofing fiber. The flame-resistant fiber is then subjected to carbonization (pre-carbonization) treatment at 300 to 800 ° C. in a nitrogen atmosphere, and in order to further promote carbonization and graphitization (high crystallization of carbon), etc. In an inert gas atmosphere, carbonization is preferably performed at 800 to 2500 ° C, more preferably 1200 to 2100 ° C.
このようにして得られた炭素繊維に対して、引き続き表面処理を行うことが好ましく、必要に応じてサイジング処理を施すことが好ましい。
このようにして得られる炭素繊維は、高強度かつ高品質であるため、複合材料の強化繊維としてスポーツ、航空宇宙用途などに用いることができる。
The carbon fiber thus obtained is preferably subsequently subjected to a surface treatment, and preferably subjected to a sizing treatment as necessary.
Since the carbon fiber thus obtained has high strength and high quality, it can be used as a reinforcing fiber for composite materials for sports, aerospace applications, and the like.
以下、実施例等をあげて本発明を具体的に説明するが、本発明は、これらの実施例等によって何等限定されるものではない。また、各実施例及び比較例における各種評価は以下の方法により実施した。 Hereinafter, the present invention will be specifically described with reference to examples and the like, but the present invention is not limited to these examples and the like. Various evaluations in each example and comparative example were performed by the following methods.
［油剤付着量］
炭素繊維前駆体繊維束を約２ｇ採取し、１０５℃で１時間乾燥した乾燥繊維質量ｗ１を測定した。その後、メチルエチルケトンによるソックスレー抽出法に準拠し、９０℃のメチルエチルケトンに炭素繊維前駆体アクリル繊維束を８時間浸漬して付着した油剤を溶媒抽出し、１０５℃で１時間乾燥した乾燥繊維質量ｗ２を測定し、下記式により油剤の付着量を求めた。
油剤付着量［質量％］＝（ｗ１−ｗ２）／ｗ１×１００
[Oil agent adhesion amount]
About 2 g of carbon fiber precursor fiber bundles were collected, and the dry fiber mass w 1 dried at 105 ° C. for 1 hour was measured. Then, in accordance with the Soxhlet extraction method using methyl ethyl ketone, the oil agent adhered by immersing the carbon fiber precursor acrylic fiber bundle in 90 ° C. methyl ethyl ketone for 8 hours was subjected to solvent extraction, and the dry fiber mass w 2 dried at 105 ° C. for 1 hour was determined. Measured, and the adhesion amount of the oil was obtained by the following formula.
Oil amount [mass%] = (w 1 −w 2 ) / w 1 × 100
［繊維中の油剤浸透評価］
炭素繊維前駆体繊維をシリコン平板に固定し、エポキシ樹脂で包埋した後、ライカマイクロシステムズ株式会社製電顕用試料作製装置 ウルトラミクロトーム ＵｌｔｒａｃｕｔＳを用いて、５０ｎｍ〜１００ｎｍの超薄切片を作製した。得られた超薄切片を、Ｃｕグリッドに載せ、日本電子株式会社製透過電子顕微鏡 ＪＥＭ−２８００／ＥＤＳを用いて、加速電圧２００ｋＶで、走査透過顕微鏡観察しエネルギー分散型Ｘ線分光分析（ＳＴＥＭ／ＥＤＳ分析）を行い、繊維表面から１μｍの箇所のＣ、Ｎ、Ｏ、Ｓｉ原子の定量評価を行った。かかる装置におけるＳｉ原子の検出限界は１．０ｗｔ％であった。各サンプルにつき、１０点測定を行い、Ｓｉ原子が１．０ｗｔ％を超えて検出された箇所が１箇所以上あった場合に油剤浸透有りとした。
[Evaluation of penetration of oil into fiber]
After fixing the carbon fiber precursor fiber to a silicon flat plate and embedding with an epoxy resin, an ultra-thin section of 50 nm to 100 nm was prepared using an electron microscope sample preparation apparatus Ultramicrotome UltracutS manufactured by Leica Microsystems. The obtained ultrathin section was placed on a Cu grid, and observed with a scanning transmission microscope at an acceleration voltage of 200 kV using a transmission electron microscope JEM-2800 / EDS manufactured by JEOL Ltd. and energy dispersive X-ray spectroscopy (STEM / EDS analysis) was performed to quantitatively evaluate C, N, O, and Si atoms at 1 μm from the fiber surface. The detection limit of Si atoms in such an apparatus was 1.0 wt%. Ten samples were measured for each sample, and when there was one or more locations where Si atoms were detected in excess of 1.0 wt%, oil penetration was considered.
［紡糸安定性］
実施例、比較例の各製造条件において１７時間の連続運転を行い、加圧スチーム延伸工程後のローラーへの巻き付き発生回数を数え、紡糸安定性を評価した。
○：巻き付き発生回数０〜３回
△：巻き付き発生回数３〜９回
×：巻き付き発生回数１０回以上
[Spinning stability]
A continuous operation for 17 hours was carried out under the production conditions of Examples and Comparative Examples, and the number of occurrences of winding around the roller after the pressurized steam stretching process was counted to evaluate the spinning stability.
○: Winding occurrence number 0-3 times Δ: Winding occurrence number 3-9 times ×: Winding occurrence number 10 times or more
［ストランド引張強度］
ＪＩＳ Ｒ−７６０８に準じてエポキシ樹脂含浸ストランドの引張強度を測定した。
[Strand tensile strength]
The tensile strength of the epoxy resin impregnated strand was measured according to JIS R-7608.
（実施例１）
塩化亜鉛水溶液を溶媒とし、単量体としてアクリロニトリル９５質量％、アクリル酸メチル４質量％、イタコン酸１質量％の割合で含む混合液を溶液重合し、ポリアクリロニトリル共重合体（重合度１．６）を含む紡糸原液（重合体濃度７．５質量％）を得た。得られた紡糸原液を濃度２５質量％の塩化亜鉛水溶液を満たした３８℃の凝固浴中に孔数６０００の紡糸ノズルより吐出し凝固糸とした。次いで、凝固糸を５０〜９５℃の温度勾配を有する水洗槽中で脱溶媒するとともに７．５倍に湿潤延伸し、さらに、圧力０．１０ＭＰａ、温度１２０℃の水蒸気中で２．０倍に気中延伸を行い、延伸糸を得た。得られた延伸糸を、アミノ変性シリコーン系油剤を主剤として３．０質量％含む油剤浴中に浸漬して油剤を付与した。なお、油剤付与前の延伸倍率は、１５．０倍であった。
油剤を付与した延伸糸を、次いで、表面温度１００℃の熱ローラーにて乾燥緻密化し、さらに表面温度１８０℃の熱ローラーにて１．０４倍に延伸し、炭素繊維前駆体繊維（油剤付着量０．４０％、単繊維繊度１．２ｄｔｅｘ、単繊維直径１１μｍ、フィラメント数６０００）を得た。前駆体繊維製造工程における総延伸倍率は１５．６倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は９６．２％であった。
(Example 1)
A mixed solution containing 95% by mass of acrylonitrile, 4% by mass of methyl acrylate, and 1% by mass of itaconic acid as a monomer was solution polymerized using a zinc chloride aqueous solution as a monomer, and a polyacrylonitrile copolymer (polymerization degree 1.6) was obtained. ) Containing a polymer solution (polymer concentration 7.5% by mass). The obtained spinning solution was discharged from a spinning nozzle having a hole number of 6000 into a coagulating bath at 38 ° C. filled with an aqueous solution of zinc chloride having a concentration of 25% by mass to obtain coagulated yarn. Next, the coagulated yarn was desolvated in a water washing tank having a temperature gradient of 50 to 95 ° C. and wet-stretched 7.5 times, and further 2.0 times in water vapor at a pressure of 0.10 MPa and a temperature of 120 ° C. In-air drawing was performed to obtain a drawn yarn. The obtained drawn yarn was immersed in an oil agent bath containing 3.0% by mass of an amino-modified silicone oil as a main agent to give an oil. In addition, the draw ratio before oil agent provision was 15.0 times.
Next, the drawn yarn to which the oil agent is applied is dried and densified with a heat roller having a surface temperature of 100 ° C., and further drawn 1.04 times with a heat roller having a surface temperature of 180 ° C. 0.40%, single fiber fineness 1.2 dtex, single fiber diameter 11 μm, filament number 6000). The total draw ratio in the precursor fiber production process was 15.6 times, and the ratio of the draw ratio before applying the oil to the total draw ratio was 96.2%.
実施例１において、ローラーへの巻き付きはなく、毛羽や糸切れは発生しなかった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
この炭素繊維前駆体繊維を空気中２５０℃で加熱して、耐炎化繊維を得た。得られた耐炎化繊維を窒素雰囲気中６００℃で予備炭素化処理を行った後、窒素雰囲気中１２００℃で炭素化処理し炭素繊維を得た。このようにして得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は、５５５０ＭＰａと高く、また、毛羽や糸切れのない高品質の炭素繊維であった。
In Example 1, there was no winding around the roller, and no fluff or yarn breakage occurred. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
This carbon fiber precursor fiber was heated in air at 250 ° C. to obtain a flame-resistant fiber. The obtained flame resistant fiber was subjected to a preliminary carbonization treatment at 600 ° C. in a nitrogen atmosphere, and then carbonized at 1200 ° C. in a nitrogen atmosphere to obtain a carbon fiber. The strand strength of the carbon fibers thus obtained was measured and shown in Table 1. The strand strength of the obtained carbon fiber was as high as 5550 MPa, and it was a high-quality carbon fiber without fuzz or yarn breakage.
（実施例２）
液中での延伸倍率を８．２倍とした以外は実施例１と同様にして炭素繊維前駆体を得た。実施例２において、油剤付与前までの延伸倍率は、１６．４倍であり、前駆体繊維製造工程における総延伸倍率は１７．１倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は９６．２％であった。
実施例２においても、ローラーへの巻き付きはなく、毛羽や糸切れは発生しなかった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例２で得られた炭素繊維前駆体を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は、５６００ＭＰａと高く、また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 2)
A carbon fiber precursor was obtained in the same manner as in Example 1 except that the draw ratio in the liquid was 8.2 times. In Example 2, the draw ratio before applying the oil agent is 16.4 times, the total draw ratio in the precursor fiber manufacturing process is 17.1 times, and the ratio of the draw ratio before applying the oil agent to the total draw ratio Was 96.2%.
Also in Example 2, there was no winding around the roller, and no fluff or yarn breakage occurred. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
Table 1 shows the strand strength of carbon fibers obtained by carbonizing the carbon fiber precursor obtained in Example 2 in the same manner as in Example 1. The strand strength of the obtained carbon fiber was as high as 5600 MPa, and it was a high-quality carbon fiber free from fuzz and yarn breakage.
（実施例３）
気中延伸の延伸倍率を１．５倍とし、油剤付与後の表面温度１８０℃の熱ローラーによる熱延伸の延伸倍率を１．２倍とした以外は実施例１と同様にして炭素繊維前駆体を得た。なお、油剤付与前までの延伸倍率は１１．３倍であり、前駆体繊維製造工程における総延伸倍率は１３．５倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は８３．３％であった。
実施例３において前駆体繊維の製造時にローラーへの巻き付きは５回あった。繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例３で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は５４８５ＭＰａと高く、また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 3)
Carbon fiber precursor in the same manner as in Example 1, except that the draw ratio for air drawing was 1.5 times and the draw ratio for heat drawing with a heat roller having a surface temperature of 180 ° C. after oil application was 1.2 times. Got. In addition, the draw ratio before oil agent provision is 11.3 times, the total draw ratio in a precursor fiber manufacturing process is 13.5 times, and the ratio of the draw ratio before oil agent provision to the total draw ratio is 83.3. %Met.
In Example 3, the winding around the roller was 5 times during the production of the precursor fiber. Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
Table 1 shows the strand strength of carbon fibers obtained by carbonizing the carbon fiber precursor fibers obtained in Example 3 in the same manner as in Example 1. The obtained carbon fiber had a high strand strength of 5485 MPa and was a high-quality carbon fiber free from fluff and yarn breakage.
（実施例４）
油剤付与後の表面温度１８０℃の熱ローラーによる熱延伸の延伸倍率を１．０４倍から１．１０倍に変更した以外は実施例１と同様にして炭素繊維前駆体を得た。なお、油剤付与前の延伸倍率は１５．０倍であり、前駆体繊維製造工程における総延伸倍率は１６．５倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は９０．９％であった。
実施例４において、前駆体繊維の製造時のローラーへの繊維の巻き付きは３回であった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例４で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は、５８００ＭＰａと高く、また、毛羽や糸切れのない高品質の炭素繊維であった。
Example 4
A carbon fiber precursor was obtained in the same manner as in Example 1 except that the draw ratio of heat drawing by a hot roller having a surface temperature of 180 ° C. after the oil agent application was changed from 1.04 times to 1.10 times. The draw ratio before applying the oil agent is 15.0 times, the total draw ratio in the precursor fiber manufacturing process is 16.5 times, and the ratio of the draw ratio before applying the oil agent to the total draw ratio is 90.9%. Met.
In Example 4, the winding of the fiber around the roller during the production of the precursor fiber was 3 times. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
Table 1 shows the strand strength of carbon fibers obtained by carbonizing the carbon fiber precursor fibers obtained in Example 4 in the same manner as in Example 1. The strand strength of the obtained carbon fiber was as high as 5800 MPa, and it was a high-quality carbon fiber free from fluff and yarn breakage.
（実施例５）
油剤付与後の表面温度１８０℃の熱ローラーによる熱延伸の延伸倍率を１．０倍に変更した以外は実施例１と同様にして炭素繊維前駆体を得た。なお、油剤付与前の延伸倍率は１５．０倍であり、前駆体繊維製造工程における総延伸倍率は１５．０倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は１００％であった。
実施例５において、前駆体繊維の製造時、ローラーへの巻き付きはなかった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例５で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は、５２５０ＭＰａと高く、また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 5)
A carbon fiber precursor was obtained in the same manner as in Example 1 except that the draw ratio of heat drawing by a hot roller having a surface temperature of 180 ° C. after the oil agent application was changed to 1.0. The draw ratio before application of the oil was 15.0 times, the total draw ratio in the precursor fiber production step was 15.0 times, and the ratio of the draw ratio before application of the oil to the total draw ratio was 100%. It was.
In Example 5, there was no winding around the roller during the production of the precursor fiber. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Example 5 in the same manner as in Example 1 was measured and shown in Table 1. The strand strength of the obtained carbon fiber was as high as 5250 MPa, and it was a high-quality carbon fiber free from fuzz and yarn breakage.
（実施例６）
気中延伸の延伸倍率を１．２倍とし、油剤付与後の表面温度１８０℃の熱ローラーによる熱延伸の延伸倍率を１．３３倍とした以外は実施例１と同様にして炭素繊維前駆体を得た。なお、油剤付与前の延伸倍率は９．０倍であり、前駆体繊維製造工程における総延伸倍率は１２．０倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は７５．２％であった。実施例６において前駆体繊維の製造時にローラーへの巻き付きは５回であった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例６で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は５１４５ＭＰａと高く、また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 6)
A carbon fiber precursor in the same manner as in Example 1 except that the stretch ratio for air stretching is 1.2 times and the stretch ratio for heat stretching with a heat roller having a surface temperature of 180 ° C. after applying the oil agent is 1.33 times. Got. The draw ratio before applying the oil agent is 9.0 times, the total draw ratio in the precursor fiber manufacturing step is 12.0 times, and the ratio of the draw ratio before applying the oil agent to the total draw ratio is 75.2%. Met. In Example 6, the winding around the roller was 5 times during the production of the precursor fiber. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Example 6 in the same manner as in Example 1 was measured and shown in Table 1. The obtained carbon fiber had a strand strength as high as 5145 MPa, and was a high-quality carbon fiber free from fluff and yarn breakage.
（比較例１）
液中での湿潤延伸後、気中延伸処理を行わず油剤を付与し、表面温度１８０℃の熱ローラーにて乾燥した後に後延伸工程として気中延伸処理を行い、さらに熱ローラーによる熱延伸を行った以外は実施例１と同様にして炭素繊維前駆体を得た。比較例１において、油剤付与前の延伸倍率は、７．５倍であり、前駆体繊維製造工程における総延伸倍率は１５．６倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は４８．１％であった。
比較例１において、前駆体繊維の製造時のローラーへの巻き付きは２０回と多く、紡糸安定性不良となった。また、繊維表面から１μｍの繊維内層において、Ｓｉ原子が１．０ｗｔ％を超えて検出された箇所が測定した１０点中、３点あり、繊維内部への油剤の浸透が確認された。
この炭素繊維前駆体を実施例１と同様にして得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は４７８０ＭＰａと低く、また、毛羽や糸切れが見られる品位の低い炭素繊維であった。
(Comparative Example 1)
After wet stretching in the liquid, an oil agent is applied without performing a stretching process in the air, and after drying with a hot roller having a surface temperature of 180 ° C., a stretching process is performed in the air as a post-stretching process. A carbon fiber precursor was obtained in the same manner as in Example 1 except for the above. In Comparative Example 1, the draw ratio before applying the oil agent is 7.5 times, the total draw ratio in the precursor fiber manufacturing process is 15.6 times, and the ratio of the draw ratio before applying the oil agent to the total draw ratio is It was 48.1%.
In Comparative Example 1, the winding of the precursor fiber on the roller was as many as 20 times, resulting in poor spinning stability. In addition, in the fiber inner layer 1 μm from the fiber surface, there were 3 points out of 10 points where Si atoms were detected in excess of 1.0 wt%, and the penetration of the oil into the fiber was confirmed.
The strand strength of carbon fibers obtained from this carbon fiber precursor in the same manner as in Example 1 was measured and shown in Table 1. The obtained carbon fiber had low strand strength of 4780 MPa, and was a low-quality carbon fiber in which fuzz and yarn breakage were observed.
（比較例２）
液中延伸の延伸倍率を３．０倍とした以外は実施例１と同様にして炭素繊維前駆体を得た。なお、油剤付与前の延伸倍率は、６．０倍であり、前駆体繊維製造工程における総延伸倍率は６．２倍であり、総延伸倍率に対する油剤付与前の延伸倍率の割合は９６．２％であった。
比較例２において前駆体繊維の製造時にローラーへの巻き付きはなかったが、繊維表面から１μｍの繊維内層においてＳｉ原子が１．０ｗｔ％を超えて検出された箇所が測定した１０点中、５点あり、繊維内部への油剤の浸透が確認された。
比較例２で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定し、表１に示した。得られた炭素繊維のストランド強度は４２１０ＭＰａと低く、また、毛羽や糸切れが多くみられる品位の低い炭素繊維であった。
(Comparative Example 2)
A carbon fiber precursor was obtained in the same manner as in Example 1 except that the draw ratio of in-liquid drawing was changed to 3.0 times. In addition, the draw ratio before oil agent provision is 6.0 times, the total draw ratio in a precursor fiber manufacturing process is 6.2 times, and the ratio of the draw ratio before oil agent provision to the total draw ratio is 96.2. %Met.
In Comparative Example 2, there was no winding around the roller during the production of the precursor fiber, but 5 points out of 10 points where the location where Si atoms were detected exceeding 1.0 wt% in the fiber inner layer of 1 μm from the fiber surface were measured. Yes, the penetration of the oil into the fiber was confirmed.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Comparative Example 2 in the same manner as in Example 1 was measured and shown in Table 1. The obtained carbon fiber had a low strand strength of 4210 MPa, and was a low-quality carbon fiber in which many fluff and yarn breakage were observed.
（実施例７）
アクリロニトリル系重合体の単量体組成を、アクリロニトリル９６質量％、アクリルアミド３質量％、メタクリル酸１質量％に変更した以外は実施例１と同様にして炭素繊維前駆体を得た。実施例７において、前駆体繊維の製造時、ローラーへの巻き付きはなかった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例７で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定した。得られた炭素繊維のストランド強度は、５５００ＭＰａと高く、また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 7)
A carbon fiber precursor was obtained in the same manner as in Example 1 except that the monomer composition of the acrylonitrile polymer was changed to 96% by mass of acrylonitrile, 3% by mass of acrylamide, and 1% by mass of methacrylic acid. In Example 7, there was no winding around the roller during the production of the precursor fiber. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Example 7 in the same manner as in Example 1 was measured. The strand strength of the obtained carbon fiber was as high as 5500 MPa, and it was a high-quality carbon fiber free from fuzz and yarn breakage.
（実施例８）
用いる溶媒を塩化亜鉛水溶液からチオシアン酸ナトリウム水溶液に変更した以外は実施例１と同様にして炭素繊維前駆体を得た。実施例８において、前駆体繊維の製造時、ローラーへの巻き付きはなかった。また、繊維内部において、繊維内層部のＳｉ原子の存在量は測定したすべての箇所において検出限界の１．０ｗｔ％を下回っておりＳｉ原子は存在せず、繊維内部へ油剤が浸透していないことが確認できた。
実施例８で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定した。得られた炭素繊維のストランド強度は、５３００ＭＰａと十分満足できる強度を有していた。また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 8)
A carbon fiber precursor was obtained in the same manner as in Example 1 except that the solvent used was changed from an aqueous zinc chloride solution to an aqueous sodium thiocyanate solution. In Example 8, there was no winding around the roller during the production of the precursor fiber. In addition, within the fiber, the amount of Si atoms in the fiber inner layer is less than the detection limit of 1.0 wt% in all the measured positions, no Si atoms are present, and the oil does not penetrate into the fiber. Was confirmed.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Example 8 in the same manner as in Example 1 was measured. The strand strength of the obtained carbon fiber had a sufficiently satisfactory strength of 5300 MPa. Moreover, it was a high-quality carbon fiber with no fuzz or yarn breakage.
（実施例９）
紡糸溶液を、懸濁重合で得られた重合体を重合体濃度が２２質量％となるようにジメチルホルムアミドに溶解して得られた紡糸溶液に変更し、凝固浴の溶剤濃度を４０質量％に変更した以外は実施例１と同様にして炭素繊維前駆体を得た。実施例９において、前駆体繊維の製造時、ローラーへの巻き付きはなかった。また、繊維内層部の繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例９で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定した。得られた炭素繊維のストランド強度は、５２５０ＭＰａと十分満足できる強度を有していた。また、毛羽や糸切れのない高品質の炭素繊維であった。
Example 9
The spinning solution was changed to a spinning solution obtained by dissolving the polymer obtained by suspension polymerization in dimethylformamide so that the polymer concentration was 22% by mass, and the solvent concentration of the coagulation bath was changed to 40% by mass. A carbon fiber precursor was obtained in the same manner as in Example 1 except for the change. In Example 9, there was no winding around the roller during the production of the precursor fiber. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface of the fiber inner layer portion, and it was confirmed that the oil did not penetrate into the fiber.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Example 9 in the same manner as in Example 1 was measured. The strand strength of the obtained carbon fiber had a sufficiently satisfactory strength of 5250 MPa. Moreover, it was a high-quality carbon fiber with no fuzz or yarn breakage.
（実施例１０）
用いる溶媒をジメチルスルホキシドに変更した以外は実施例９と同様にして炭素繊維前駆体を得た。実施例１０において、前駆体繊維の製造時、ローラーへの巻き付きはなかった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例１０で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定した。得られた炭素繊維のストランド強度は、５２８０ＭＰａと十分満足できる強度を有していた。また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 10)
A carbon fiber precursor was obtained in the same manner as in Example 9 except that the solvent used was changed to dimethyl sulfoxide. In Example 10, there was no winding around the roller during the production of the precursor fiber. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Example 10 in the same manner as in Example 1 was measured. The strand strength of the obtained carbon fiber had a sufficiently satisfactory strength of 5280 MPa. Moreover, it was a high-quality carbon fiber with no fuzz or yarn breakage.
（実施例１１）
紡糸溶液を、懸濁重合で得られた重合体を重合体濃度が２０質量％となるようにジメチルアセトアミドに溶解して得られた紡糸溶液に変更し、凝固浴の溶剤濃度を６５質量％に変更した以外は実施例１と同様にして炭素繊維前駆体を得た。実施例１１において、前駆体繊維の製造時、ローラーへの巻き付きはなかった。また、繊維表面から１μｍの繊維内層でＳｉ原子は検出されず、繊維内部へ油剤が浸透していないことが確認できた。
実施例１１で得られた炭素繊維前駆体繊維を実施例１と同様に炭素化処理して得られた炭素繊維のストランド強度を測定した。得られた炭素繊維のストランド強度は、５４２０ＭＰａと十分満足できる強度を有していた。また、毛羽や糸切れのない高品質の炭素繊維であった。
(Example 11)
The spinning solution was changed to a spinning solution obtained by dissolving the polymer obtained by suspension polymerization in dimethylacetamide so that the polymer concentration was 20% by mass, and the solvent concentration of the coagulation bath was changed to 65% by mass. A carbon fiber precursor was obtained in the same manner as in Example 1 except for the change. In Example 11, there was no winding around the roller during the production of the precursor fiber. Further, Si atoms were not detected in the fiber inner layer 1 μm from the fiber surface, and it was confirmed that the oil did not penetrate into the fiber.
The strand strength of the carbon fiber obtained by carbonizing the carbon fiber precursor fiber obtained in Example 11 in the same manner as in Example 1 was measured. The strand strength of the obtained carbon fiber had a sufficiently satisfactory strength of 5420 MPa. Moreover, it was a high-quality carbon fiber with no fuzz or yarn breakage.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014082800A JP6359860B2 (en) | 2014-04-14 | 2014-04-14 | Carbon fiber precursor fiber and method for producing carbon fiber precursor fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014082800A JP6359860B2 (en) | 2014-04-14 | 2014-04-14 | Carbon fiber precursor fiber and method for producing carbon fiber precursor fiber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2015203166A true JP2015203166A (en) | 2015-11-16 |
| JP6359860B2 JP6359860B2 (en) | 2018-07-18 |
Family
ID=54596803
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2014082800A Active JP6359860B2 (en) | 2014-04-14 | 2014-04-14 | Carbon fiber precursor fiber and method for producing carbon fiber precursor fiber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6359860B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20220170183A1 (en) * | 2019-03-28 | 2022-06-02 | Toray Industries, Inc. | Carbon fiber bundle and production method thereof |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61167024A (en) * | 1985-01-21 | 1986-07-28 | Mitsubishi Rayon Co Ltd | Production of carbon yarn tow |
| JPH04257313A (en) * | 1991-02-08 | 1992-09-11 | Mitsubishi Rayon Co Ltd | Production of precursor fiber for carbon fiber |
| JPH04281008A (en) * | 1991-03-01 | 1992-10-06 | Mitsubishi Rayon Co Ltd | Acrylonitrile-based precursor fiber bundle |
| WO1997045576A1 (en) * | 1996-05-24 | 1997-12-04 | Toray Industries, Inc. | Carbon fiber, acrylic fiber, and method of manufacturing them |
| JPH11217734A (en) * | 1997-11-21 | 1999-08-10 | Toray Ind Inc | Carbon fiber and its production |
| JPH11241230A (en) * | 1997-12-11 | 1999-09-07 | Toray Ind Inc | Carbon fiber, precursor fiber for carbon fiber, composite material and production of carbon fiber |
| JP2009221619A (en) * | 2008-03-14 | 2009-10-01 | Toho Tenax Co Ltd | Precursor fiber and method for producing precursor fiber, flame-resistant fiber and carbon fiber |
| JP2011012363A (en) * | 2009-07-02 | 2011-01-20 | Mitsubishi Rayon Co Ltd | Fiber bundle of carbon fiber precursor and method for producing the same |
-
2014
- 2014-04-14 JP JP2014082800A patent/JP6359860B2/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61167024A (en) * | 1985-01-21 | 1986-07-28 | Mitsubishi Rayon Co Ltd | Production of carbon yarn tow |
| JPH04257313A (en) * | 1991-02-08 | 1992-09-11 | Mitsubishi Rayon Co Ltd | Production of precursor fiber for carbon fiber |
| JPH04281008A (en) * | 1991-03-01 | 1992-10-06 | Mitsubishi Rayon Co Ltd | Acrylonitrile-based precursor fiber bundle |
| WO1997045576A1 (en) * | 1996-05-24 | 1997-12-04 | Toray Industries, Inc. | Carbon fiber, acrylic fiber, and method of manufacturing them |
| US6103211A (en) * | 1996-05-24 | 2000-08-15 | Toray Industries, Inc. | Carbon fibers, acrylic fibers, and production processes thereof |
| JPH11217734A (en) * | 1997-11-21 | 1999-08-10 | Toray Ind Inc | Carbon fiber and its production |
| JPH11241230A (en) * | 1997-12-11 | 1999-09-07 | Toray Ind Inc | Carbon fiber, precursor fiber for carbon fiber, composite material and production of carbon fiber |
| JP2009221619A (en) * | 2008-03-14 | 2009-10-01 | Toho Tenax Co Ltd | Precursor fiber and method for producing precursor fiber, flame-resistant fiber and carbon fiber |
| JP2011012363A (en) * | 2009-07-02 | 2011-01-20 | Mitsubishi Rayon Co Ltd | Fiber bundle of carbon fiber precursor and method for producing the same |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20220170183A1 (en) * | 2019-03-28 | 2022-06-02 | Toray Industries, Inc. | Carbon fiber bundle and production method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6359860B2 (en) | 2018-07-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2018145540A (en) | Method for production of carbon fiber bundle | |
| KR101656976B1 (en) | Carbon fiber bundle and method of producing carbon fiber bundle | |
| JP5313788B2 (en) | Carbon fiber precursor fiber bundle and method for producing the same | |
| JP5741815B2 (en) | Carbon fiber precursor acrylic fiber bundle and carbon fiber bundle | |
| JP2010100970A (en) | Method for producing carbon fiber | |
| JP6359860B2 (en) | Carbon fiber precursor fiber and method for producing carbon fiber precursor fiber | |
| JP2007186802A (en) | Method for producing flame retardant fiber and carbon fiber | |
| JP2011017100A (en) | Method for producing carbon fiber | |
| JP7447788B2 (en) | Carbon fiber bundle and its manufacturing method | |
| WO2020071445A1 (en) | Precursor fiber bundle production method, carbon fiber bundle production method, and carbon fiber bundle | |
| JP2017137614A (en) | Carbon fiber bundle and manufacturing method thereof | |
| JP2017137602A (en) | Manufacturing method of polyacrylonitrile fiber bundle | |
| JP5667380B2 (en) | Flame-resistant fiber bundle, carbon fiber bundle, and production method thereof | |
| JP2007321267A (en) | Method for producing polyacrylonitrile-based fiber and carbon fiber | |
| JP2021139062A (en) | Production method of carbon fiber bundle | |
| JP2015183166A (en) | Acrylonitrile-based copolymer, acrylonitrile-based carbon fiber precursor fiber and method for producing carbon fiber | |
| JP4715386B2 (en) | Carbon fiber bundle manufacturing method | |
| JP2004060126A (en) | Carbon fiber and method for producing the same | |
| JP5842343B2 (en) | Method for producing carbon fiber precursor acrylic fiber bundle | |
| WO2023140212A1 (en) | Carbon fiber bundle | |
| JP6232814B2 (en) | Acrylic fiber manufacturing method | |
| KR101364788B1 (en) | Process for treating oil on the precursor fiber for preparing a carbon fiber | |
| JP7087740B2 (en) | Manufacturing method of carbon fiber bundle | |
| JP7408406B2 (en) | Method for manufacturing flame-resistant fiber bundle, method for manufacturing carbon fiber bundle, and connection device | |
| JP6729665B2 (en) | Acrylonitrile precursor fiber bundle for carbon fiber and method for producing the same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20170210 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20171215 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20171226 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20180220 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20180529 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20180621 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6359860 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |