METHOD FOR MANUFACTURING CARBON FIBER

• Main Authors: OHARA MINAMI, HATANAKA YOJI, KACHI AKIRA, TSUDA TAKAAKI
• Format: Patent
• Language: English; Japanese
• Published: 28.09.2015
• Subjects: APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBONFILAMENTS; CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS,THREADS, FIBRES, BRISTLES OR RIBBONS; NATURAL OR ARTIFICIAL THREADS OR FIBRES; SPINNING; TEXTILES

PROBLEM TO BE SOLVED: To provide a method for manufacturing a carbon fiber bundle, capable of evenly sending hot wind to a carbon fiber precursor fiber bundle, and improving a wind velocity of hot wind to spray to each of the fiber bundles without increasing a total hot wind quantity to be supplied to a heat treatment furnace.SOLUTION: A method for manufacturing a carbon fiber bundle 8 includes subjecting the carbon fiber precursor fiber bundle 8 to flame-resistant treatment. The flame-resistant treatment satisfies (1)-(3) as follows: (1) folding the sheet-like carbon fiber precursor fiber bundle 8 a plurality of times followed by travelling in multiple stages in a heat treatment chamber 2, and applying hot wind in parallel to the longitudinal direction of the fiber bundle 8; (2) there are included between two adjacent sheets of the fiber bundles 8 in the heat treatment chamber 2, a first hot wind area 14 having a plurality of hot wind flows in a direction where the sheets are overlapped, and a second hot wind area 15 which is at the downstream of the first hot wind area 14, and where at least two of hot wind flows mixedly flow; and (3) a hot wind passage cross sectional area of the first hot wind area 14 is larger than a hot wind passage cross sectional area of the second hot wind area 15. 【課題】炭素繊維前駆体繊維束に均等に熱風を送ることが可能で、さらに熱処理炉に供給する総熱風量を増すことなく、各繊維束に吹き付ける熱風の風速を向上することが可能な、炭素繊維束の製造方法を提供する。【解決手段】炭素繊維前駆体繊維束８を耐炎化処理することを含む、炭素繊維束８の製造方法であって、前記耐炎化処理が、下記の（１）〜（３）を満足する。（１）シート状の炭素繊維前駆体繊維束８を複数回折り返して、熱処理室２内を多段で走行させ、繊維束８の長手方向に対して平行に熱風をあてる。（２）熱処理室２内に、隣り合う２シートの繊維束８の間に、シートの重なる方向において複数の熱風の流れを有する第一熱風区域１４と、該第一熱風区域１４の下流にあり、熱風の流れの２つ以上が混合して流れる第二熱風区域１５を有する。（３）第一熱風区域１４の熱風流路断面積は、第二熱風区域１５の熱風流路断面積より大きい。【選択図】図５