Production of carbon yarn

[Detailed Description of the Invention]

[Field of the Invention] The present invention relates to carbon fiber and relates to the manufacturing method of carbon fiber with which especially improvement in tensile strength was achieved. [Background of the Invention] Carbon fiber is excellent in heat resistance and mechanical strength, and, moreover, the use is achieved in various fields from the lightweight thing. By the way, it is known that the intensity of pitch system carbon fiber and elasticity will be dependent on the Orientation of textiles. However, in the field of the conventional carbon fiber, it was thought that the Orientation of textiles was chiefly determined uniquely by the crystalline grade and fusion silk-thread-spun conditions of silk-thread-spun materials. Therefore, in order to raise the tensile strength of textiles, it is necessary to control strictly silk-thread-spun materials, its adjustment, and fusion silk-thread-spun conditions, and, so, process control becomes complicated by the conventional method, and there is a problem that it is not satisfactory enough [ not necessarily ] in respect of the strong improvement effect. [Summary of the Invention] The present invention is made in view of the point mentioned above, and it aims at providing the method for obtaining the carbon fiber which was excellent in tensile strength by the comparatively simple means. A manufacturing method of the carbon fiber which starts the present invention in order to achieve such an object, Non-deliquesce is carried out so that the degree for Arrangement which carry out the fusion silk thread spun of the pitch which shows optical anisotropy, increase raw textiles by the f'4 It was back, and increase these raw textiles with non-deliquesce may not exceed 2 times, and it is characterized by carbonizing the non-deliquescent fiber by which non-deliquesce was subsequently carried out by doing in this way. Conventionally, the trial which improves a non-deliquesce process is proposed variously (for example, JP,60-126323,A, 59-30915, a 58-45277 gazette). However, each of these methods is turned to the prevention from fusion between textiles, or improvement in manufacturing efficiency. on the other hand, the method of raising the intensity of textiles is also proposed by applying tension to raw textiles at the time of non-deliquesce -- Listen (JP,59-144624,A) -- the point of handling of the raw textiles in the case of non-deliquesce processing, and control of tension - it cannot necessarily be said as a simple method. In Toward" D, in the method of the present invention, the intensity of textiles makes remarkable change of the degree for Arrangement at the time of non-deliquesce by the simple method of restricting in a specific range. [Detailed description of the invention] Hereinafter, the present invention is explained still in detail. Especially"%" that expresses a quantity ratio in the following statements, unless it refuses, it is considered as weight-ization. The pitch for silk thread spun The pitch for silk thread spun used as materials consists of a pitch which shows the optical anisotropy adjusted from oil system heavy crude oil and Carboniferous system heavy crude oil. As for this pitch, in order to make Orientation good and to obtain the textiles of high intensity, meso face Including omega is preferred and it is [ 7096 or more ] desirable that it is 90% or more still more preferably. Although the pitch which makes a meso face the main ingredients is preferred at 1- which carbonization is performed, a molecule's carrying out for Arrangement in accordance with a textiles axis, and holding those [ these ] for Arrangement at the time of fusion silk thread spun, and obtains the textiles of high intensity, Even if improvement in molecular orientation nature cannot expect so much that they are a noodle face content or less than 70% but it performs non-deliquesce to less than +two degrees for Arrangement of raw textiles, a strong Toward-L effect is not preferred from a small thing. Fusion silk thread spun Silk thread spun of the above-mentioned pitch can obtain raw textiles by a publicly known method conventionally, and the conditions of fusion silk thread spun, for example, silk-thread-spun temperature, silk-thread-spun speed in particular, etc. are not limited, and may be chosen suitably. Non-deliquesce Non-deliquesce processing is performed to the raw textiles produced by performing it above. In the present invention, it is important to carry out so that the degree for Arrangement which increase non-deliquesce [ this ] with non-deliquesce may not exceed 2 times. Since the mechanical property of the textiles obtained by carbonization treatment especially tensile strength, and an elastic modulus will fall if an increased part of the degree for Arrangement exceeds 2 times, it is not desirable. Non-deliquesce may be performed by heating, for example in the air. The heating temperature at this time is below 250 degreeC, preferably below 230 degreeC. Since it will become difficult to control the degree for Arrangement of non-deliquescent fiber to less than +two degrees for Arrangement of raw textiles and the tensile strength after carbonization will fall if heating temperature exceeds 250 degreeC, it is not desirable. Non-deliquesce processing time is also chosen so that the degree conditions for Above may be suited. In order to control the increase in the degree for Arrangement in a mentioned range, the above-mentioned non-deliquesce conditions can be set up by making keeping a part for Quinoline fusion of non-deliquescent fiber from exceeding 70% into a standard. In accordance with a publicly known method, M1 law of the degree for Arrangement which serve as Base fluorine of the grade of Orientation in the present invention may be carried out from the diffraction intensity distribution curve in alignment with the Debye ring by a wide angle X diffraction. It is indicated by modern edit company issue and the "carbon fiber" of Chapter 12 about the concrete method related with the degree measurement for Arrangement. Conventionally, the tensile strength resulting from Orientation and this Orientation of carbon fiber was generally considered to be a thing depending on the crystalline grade and fusion silk-thread-spun conditions of a silk-thread-spun materials pitch. In the present invention, the carbon material which increased in number to the conventional material by the simple north Comparison method of controlling the Orientation of the textiles for non-deliquesce under the above-mentioned specific condition, and was excellent in mechanical strength can be obtained. Carbonization Carbon fiber is obtained by carbonizing the textiles by which non-deliquesce processing was carried out, and also carrying out graphitization processing if needed. Carbonization treatment follows a usual state method and may be performed by calcinating by 1000~1500 degreeC in inactive gas atmosphere, such as N2 gas. Subsequently, it can graphitize by heating to 2000~3000 degreeC. With, although Do and the present invention are explained based on an example, the present invention is not restricted to the statement of this example. EXAMPLE carrying out the fusion silk thread spun of the silk-thread-spun pitch of an oil system whose optical anisotropic phase is 100% and whose softening temperature is 238degreeC -- average yarn diameter of 11 micrometers 1 Quinoline fusion -- the raw textiles of 22 degrees for Arrangement were obtained 23% per part. Subsequently, the amount of Quinoline fusion was [ 44 weight ?6 and the degree for Arrangement of textiles after Temperature rising(ing) these raw textiles to 200degreeC by a part for 2 degreeC/among air atmosphere and carrying out non-deliquesce processing by 200 degreeC for 6 hours ] 23 degrees. Thus, the physical properties of the carbon fiber after carrying out carbonization treatment of the textiles after non-deliquesce [ which was obtained ] by 1000 degreeC among N2 gas atmosphere for 1 hour were tensile strength 300 kg/si and elastic-modulus 20 TON/In 1j1. Comparative example The amount of Quinoline fusion was [ the degree for Arrangement of textiles after Temperature rising(ing) the raw textiles obtained in the above-mentioned example to 290degreeC by a part for 2 degreein air atmosphere C/and carrying out non-deliquesce processing for 30 minutes by 290 degreeC ] 26 degrees 83% of the weight. oxygen element 6a in the textiles after non-deliquesce [ which was produced by doing in this way ] -- the binary was the same value as the textiles after non-deliquesce [ which was obtained in the example ]. Carrying out carbonization treatment of the textiles after non-deliquesce [ this ] on an example and the conditions, the physical properties of 117 Was done carbon fiber were tensile strength 240 kg/i and elastic-modulus 16TON /mA. An i'1lll constant standard In the six above-mentioned examples, M1 law of the part for Quinoline fusion was carried out in accordance with the method of JIS-K-2425. The degree for Arrangement is "carbon fiber" (Showa a modern edit published by company, f mouth 58-year revised edition). WJ law was carried out in accordance with the method indicated to 644 page~646L''f.