JP4479067B2 - Method for producing polyamide fiber - Google Patents

Description

【００２７】
【発明の効果】
本発明によれば、一工程法の多糸条取りかつ省スペースで、高強度でかつ糸斑異常のない繊維を製造することが可能である。
【図面の簡単な説明】
【図１】本発明のポリアミド繊維を製造するための紡糸延伸工程の一態様を示す概略図である。
【符号の説明】
１．紡糸口金
２．冷却装置
３．油剤付与装置
４．第１ゴデローラ
５．輻射式熱処理装置
６．第２ゴデローラ
７．巻き取り装置
Ｙ.糸条[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a production method for directly spinning and drawing polyamide fibers.
[0002]
[Prior art]
The production method of polyamide fibers such as nylon 6 and nylon 66 includes a two-stroke method in which a spun yarn is temporarily wound and stretched in the next stroke, and a speed difference between the godet rollers immediately without being wound once after spinning. There are one-step methods such as direct spinning and drawing methods that use mechanical drawing, such as direct spinning, and direct spinning methods that omit the drawing step by pulling at high speed. It is used in various fields regardless of materials. In this one-step method, as a means for stretching the yarn, a method of mechanically stretching the yarn by passing on rollers with different surface speeds, air, water vapor, etc. in a state where stress is applied to the yarn In general, a method of heating and softening a yarn with a heating medium and drawing the yarn with a stress of the yarn is generally used.
[0003]
When trying to obtain high-strength fibers by these methods, the following various problems occur. When trying to obtain high-strength fibers by the former method, it is necessary to stretch at a high magnification between rollers. In this case, in order to prevent slippage between the roller surface and the yarn, the contact length between the yarn and the roller surface is increased by winding the roller multiple times using a long Nelson roller or increasing the diameter of the roller. However, the stretching tension is reduced by adding a roller to multi-stage stretching to distribute the magnification among the stretching rollers, but using any of these methods, the length of the godet roller is increased. Increase in production facilities due to diameter increase and addition of rollers.
[0004]
In addition, when the latter method is used, it is necessary to uniformly heat all yarns and all filaments in the heater in order to reduce variation in yarn physical properties between the yarns of the drawn yarn and between the filaments. It is necessary to use a heating medium having a large heat capacity and to heat the yarn before the yarns converge. In this case, since the converging position of the yarn is after the outlet of the heater, the spinning stress becomes high due to the accompanying airflow of the yarn in thin varieties with high single yarn fineness and high-speed spinning conditions, leading to a decrease in yield due to yarn breakage, There was a problem that the strength of the yarn when adjusted to the same elongation was lowered. Furthermore, when steam is used, the production facilities are increased in size by steam piping, drain piping, or the like.
[0005]
As another method, in order to reduce the variation in yarn physical properties between filaments, a method of heat treating the yarn before the yarn is converged, that is, before passing through the oil application device, is disclosed in JP-A-10-292221 and JP-A-10- This is proposed in the 121320 publication.
[0006]
[Problems to be solved by the invention]
However, this method not only eliminates the hardness difference in the filament, but also moves the converging position of the yarn to the downstream side, so that the associated airflow of the yarn under thin varieties and high-speed spinning conditions. As a result, the spinning stress increases, resulting in a decrease in yield due to yarn breakage and a decrease in the strength of the yarn when adjusted to the same elongation.
[0007]
In the yarn heating by a non-contact dry heat method such as a radiant heat treatment method, the present inventors transmit a radiant wave to the filament located in the center of the yarn bundle or to the inner layer of the filament due to the transmission of the radiant wave. It has been found that a high-strength filament excellent in uniformity can be obtained without substantially causing a difference in physical properties between or within the filaments described above because it reaches and is uniformly heated.
[0008]
The present invention solves the above-described problems and provides a method for producing polyamide fibers in a single-step multi-thread take-up and space-saving, and capable of obtaining high-strength fibers. .
[0009]
[Means for Solving the Problems]
As a result of intensive studies to solve the above problems, the present inventors have reached the present invention. That is, in the present invention, after spinning and cooling the polyamide, the oil is supplied, and then wound around the first godet roller for less than one turn, and subsequently wound around the heated second godet roller for less than one turn and stretched between the first godet roller and the second godet roller. a method for winding after the non-contact radiant heat treatment heater provided between the second Goderora and the first Goderora, polyamide fiber characterized that you heat the the yarn at 200 ° C. or higher temperatures The gist of the manufacturing method.
[0010]
In the present invention, the godet roller is composed of a single first godet roller for take-up and a single second godet roller that subsequently changes the direction of the yarn path downward. It is more preferable that the surface temperature of the 2-godele roller is 110 ° C. or higher. In the present invention, it is more preferable to satisfy the following range when the surface speed of the first godet roller is V1 (m / min) and the speed of the second godet roller is V2 (m / min).
1 <V2 / V1 <3
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a schematic view of a process for producing a polyamide fiber schematically represented by using a non-contact radiant heat treatment apparatus for multiple yarns in the direct spinning drawing method of the present invention as an example of an embodiment of the present invention.
[0012]
First, polyamide is melt-spun from the spinneret 1, and the spun yarn Y is cooled and solidified by a cooling device 2 that is cooled by blowing cooling air, and an oil agent is applied by an oil agent applying device 3.
After the yarn that has passed through the oil application device and the filaments are gathered is taken up by the take-up roller 4 that is the first godet roller, the yarn is heated by the non-contact type radiation heat treatment device 5. Subsequently, after passing through the second godet roller 6 and the like, the take-up device 7 takes up the roll.
[0013]
First, in the present invention, the melt-spun yarn is once cooled and solidified by a cooling device, and subsequently an oil agent is applied by an oil agent applying device, the filaments are converged and taken up by a first godet roller, and then the first godet roller and the second godet roller are In a non-contact radiative heat treatment apparatus. By performing this heat treatment by a radiant heat treatment method, even when the filaments are converged, each filament can be uniformly heated without any difference between the filaments, thereby improving the stability in the heat treatment apparatus or before and after passing through the heat treatment, It is possible to obtain a fiber having excellent uniformity with little difference in physical properties between filaments and yarns.
[0014]
In the heat treatment apparatus is necessary to use a dry heater of non-contact as yarn heat method, using the congestion Ishiki heat treatment lateral heater. In the conventional heating method using heating medium such as heated air and water vapor, when the heat treatment is performed with the filaments converged, the filaments are heated and softened preferentially from the filament facing the outside, and the results are softened without increasing the temperature. Stress concentrates on the inner filaments that are not. As a result, there is a difference in physical properties between the heated filament and the unheated filament, and the strength as a yarn is reduced.
[0015]
The same thing occurs in the filament. That is, when the filament is heated by a contact method using a heat medium, the temperature is increased from the outside of the filament, so that a temperature difference and a hardness difference occur between the surface layer and the inner layer of the filament. By stretching in this state, stress is concentrated on the central portion having high hardness, and the orientation state of the polyamide molecules in the filament becomes non-uniform in the cross-sectional direction, resulting in a decrease in the strength of the filament.
[0016]
The yarn heat in congestion Ishiki heat treatment method of non-contact with this, the filaments located in the heart of the yarn bundle by permeable radiant wave, also receive an radiation wave to the inner layer of the filament, uniformly heated Therefore, a high-strength filament excellent in the degree of uniformity can be obtained without substantial difference in physical properties between or within the filaments described above. However, when a contact-type heat treatment device is used, a temperature difference occurs between the contact portion of the yarn with the heat treatment device and the other portions of the yarn, resulting in a difference in physical properties within and between the filaments, which causes a decrease in strength. It becomes.
[0017]
In the heat treatment, the heating temperature is preferably 200 ° C. or higher and lower than 1000 ° C. When the temperature is 200 ° C. or higher and lower than 1000 ° C., the filament hardness and spinning stress can be lowered to a level at which drawing is possible, and the drawing effect by the heat treatment apparatus is exhibited. Moreover, it is preferable that it is in this temperature range also from stabilization of productivity.
[0018]
Moreover, it is preferable that the surface temperature of a 2nd godie roller is 110 degreeC or more.
[0019]
The fiber manufacturing process to which the heat treatment apparatus is applied is not particularly limited, but it is preferably a one-step method from the viewpoint of production efficiency, and moreover, it is taken up from the viewpoint of space-saving multi-threading and downsizing of the drawing apparatus. More preferably, it is a one-side stretch method in which a single first godet roller and a single second godet roller that changes the direction of the yarn path downward are formed, and both rollers have a winding angle of less than one turn. Further, the ratio V2 / V1 between the surface speed V1 (m / min) of the first godet roller and the speed V2 (m / min) of the second godet roller is preferably more than 1 and less than 3 in order to stabilize the productivity. .
[0020]
【Example】
Next, the present invention will be specifically described with reference to examples. In addition, the measurement of the characteristic value in an Example was performed as follows.
(1) Using a tensile elongation tester (TENSILON RTM-100 manufactured by ORIENTEC), a stress strain curve was obtained under the conditions of a material length of 50 cm and a tensile speed of 100 cm / min.
[0021]
(2) Measurement was performed using a yarn spot Wooster yarn spot measuring device (USTER TESTER II manufactured by ZELLWGER).
[0022]
(3) Yarn speed and slip amount Yarn speed was measured using a laser Doppler yarn speedometer (TYPE6200 manufactured by MALVERN). The slip amount was determined from the difference between the yarn speed on the godet roller and the surface speed of the godet roller obtained by the above measurement, and the slip amount was determined to be 5 m / min or more.
Slip amount = (thread speed on the godele roller) − (godele roller surface speed) (m / min).
[0023]
Examples 1-2 and Comparative Examples 1-2
A polyamide fiber was produced according to the process shown in FIG. Nylon 6 chips having a relative viscosity (96% sulfuric acid as a solvent, sample concentration of 1 g / l, measured at room temperature of 25 ° C.) of 2.62 are fed to a melt extruder and melted at a spinning temperature of 270 ° C. It was discharged from a spinneret 1 having 20 25 mm spinning holes. The yarn Y is cooled by blowing cooling air from the cooling device 2 at an air temperature of 20 ° C. and an air speed of 30 m / min, the oil agent is applied by the oil agent applicator 3, the yarn is converged, and the yarn is moved to the first godet roller 4 Then, it was passed through a non-contact radiant heat treatment apparatus 5 and heat treated by radiant waves. The yarn exiting the heat treatment apparatus was taken up at 4000 m / min through the second godet roller 6 (surface temperature 140 ° C.), and wound up at 4000 m / min with the winding apparatus 7 to obtain 17 dT / 5f fibers. At this time, the machine drawing ratio between rollers (V2 / V1) was changed within the range of 1 <V2 / V1 <3 as shown in Table 1. Table 1 shows the results of the yarn speed, slip amount, breaking elongation, and yarn segment waveform abnormality obtained on the first godet roller.
[0024]
As is apparent from Table 1, in Examples 1 and 2, there was no yarn slip on the first godele roller, and no abnormal waveform was observed in the resulting fiber yarn spots. Further, the drawing effect in the heat treatment apparatus could be effectively expressed, and a high strength and high elongation yarn could be obtained.
[0025]
For comparison, polyamide fibers were produced in the same manner as in Examples 1 to 12 except that they were not passed through the heat treatment apparatus, the characteristic values were measured, and the results are shown in Table 1. . In Comparative Examples 1 and 2, a thread slip occurred on the first godet roller, and an abnormal waveform was observed in the yarn unevenness of the obtained fiber.
[0026]
[Table 1]

[0027]
【The invention's effect】
According to the present invention, it is possible to produce a high-strength fiber free from yarn irregularities with a multi-thread take-up method and a space-saving method.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic view showing one embodiment of a spinning drawing process for producing a polyamide fiber of the present invention.
[Explanation of symbols]
1. Spinneret 2. 2. Cooling device Oiling device 4. First Goderola5. 5. Radiation heat treatment equipment Second Godola 7 Winding device Y. Yarn

Claims (3)

After spinning and cooling the polyamide, oil is supplied, and then wound around the first godet roller for less than one turn, and then wound around the heated second godet roller for less than one turn, and stretched between the first godet roller and the second godet roller and then wound. there are the first Goderora provided a non-contact radiant heat treatment heater between said second Goderora method of polyamide fiber characterized that you heat the the yarn at 200 ° C. or higher. First Goderora and second rubber Delo over La is, the surface temperature of the single second is Goderora further second Goderora that followed by a single first Goderora to change direction of the yarn path in a downward take-off is 110 The method for producing a polyamide fiber according to claim 1, wherein the temperature is equal to or higher than ° C. The method for producing a polyamide fiber according to claim 2, wherein V1 and V2 satisfy a range of the following formula when the surface speed of the first godet roller is V1 (m / min) and the speed of the second godet roller is V2 (m / min).
1 <V2 / V1 <3

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