JPH09268422A - Spin-draw of polyester fiber and unit therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a polyester fiber good in weavability and free from dyeing speck in a single step process at lower cost under a controlled draw ratio. SOLUTION: Plural polyester filaments delivered from a spinneret 1, cooled and solidified, and then passed through a non-heated 1st roller 5, a 1st heat treatment unit 6 with normal-pressure steam atmosphere, and a 2nd roller 7, successively, to conduct orientation and heat treatment of the filaments followed by winding them at a speed of 3500m/min or higher. In this spin-draw process mentioned above, both the 1st and 2nd rollers 5, 7 are operated in an one-side passing way, the distance between the 1st heat treatment unit 6 and the 2nd roller 7 is set at >=0.20m, and the circumferential length L of the 2nd roller 7 at >=0.7m.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for direct spinning and drawing a polyester fiber, and more particularly to a method and an apparatus for producing a polyester fiber having good characteristics which can be put to practical use in a polyester drawing step at low cost. It is about.

[0002]

2. Description of the Related Art In recent years, a high-speed spinning method has been adopted in which a drawing speed is set to 3000 m / min or more and a fiber satisfying practical characteristics can be obtained without drawing.
It is called a one-step method as opposed to the conventional two-step method. In this one-step method, the direct spinning and drawing method in which the spinning step and the drawing step are continuous makes it possible to control the draw ratio between the take-up roller and the draw roller, and another process in which the draw ratio cannot be controlled. That is, it has a wider range of product compatibility than the ultra-high-speed spinning method in which the material is once cooled and solidified and then directly wound, and the hot-tube spinning method in which the fiber is stretched and heat-treated by heating the fiber in a heating zone such as a hot tube. However, since the direct spinning and drawing method uses a plurality of hot rollers and separate rollers, it is a manufacturing method having a high manufacturing cost among the one-step methods in terms of apparatus cost and energy consumption. Further, in order to heat the yarn to a desired temperature, one hot roller has to be wound around the fiber yarn many times through a separate roller, which is a method with poor threading workability.

Therefore, as a method of reducing the manufacturing cost and controlling the draw ratio, there is a method of using steam as a heating medium at the time of drawing. As an example in which steam is used in the stretching step, JP-A-6-158423 and the like can be mentioned. Since this method does not use a hot roller and a separate roller, it is advantageous in terms of apparatus cost and energy consumption, but it has a drawback that the fiber yarn slips slightly on the roller. For this reason, the obtained fiber is curled to lower the weaving property, and when dyed after knitting or weaving, uneven dyeing occurs and only poor dyeing quality can be obtained.

As a conventional technique for preventing slippage, there is Japanese Patent Application Laid-Open No. 7-278952. This publication suppresses curling that occurs in the yarn obtained by increasing the winding angle around the roller and reducing the surface roughness of the roller. Although curling can be suppressed by this method, there is a limit to the suppression of slip, and it has been difficult to obtain fibers without uneven dyeing.

Therefore, as a result of the study, the inventor has determined that the distance L1 between the first heat treatment device and the second roller is 0.20 (m) or more and the circumferential length L2 of the second roller is 0.7 (m) or more. As a result, it was found that a fiber without uneven dyeing can be obtained, and the present invention was completed.

[0006]

DISCLOSURE OF THE INVENTION The present invention is a direct spinning / drawing method in which a hot roller and a separate roller are not used, the draw ratio is controlled at a lower cost, and the weavability is good and there is no uneven dyeing. It is an object of the present invention to provide a fiber manufacturing method and apparatus.

[0007]

The above-described object of the present invention is to provide a polyester fiber yarn discharged from a spinneret and solidified by cooling, a first roller which is not heated, a first heat treatment apparatus which has a normal pressure steam atmosphere, and a second heat treatment apparatus. In the direct spinning and drawing method in which the rollers are sequentially passed through to be drawn and heat-treated, and then wound at a speed of 3500 m / min or more, the first and second rollers are set as one-side hooks and the distance between the first heat treatment apparatus and the second roller is set. L
1 is 0.20 (m) or more and the peripheral length L2 of the second roller is 0.7 (m) or more. This is achieved by adopting a direct spinning and drawing method for polyester fibers.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The main dicarboxylic acid component constituting the polyester of the present invention is preferably a terephthalic acid component. Other dicarboxylic acid components may be used without departing from the object of the present invention. The main diol component constituting the polyester of the present invention is preferably ethylene glycol. Other components such as diol components such as 1,4-butanediol, 1,6-hexanediol, polyethylene glycol, polytetramethylene glycol, and 1,4-cyclohexanedimethanol do not depart from the object of the present invention. You may use it in the range. Also,
The polyester of the present invention has various additives, for example,
If necessary, a matting agent, a flame retardant, an antioxidant, an ultraviolet absorber, an infrared absorber, a crystal nucleating agent, a fluorescent whitening agent, etc. may be copolymerized or mixed.

The present invention is applied to the process of direct spinning and drawing, but in this case, winding at a speed of 3500 m / min or more has cost merit such as reduction of labor cost, equipment cost and scrap due to one process. Since it is possible to draw fibers that can be utilized and have no change in physical properties immediately after spinning, it is advantageous for uniform drawing. Taking into consideration the disadvantage of deterioration of the spinnability due to the breakage of the spun yarn due to the speed increase and the advantage of improving the productivity, the take-up speed is preferably 7,000 m / min or less.

In the direct spinning and drawing method of the present invention, the polyester fiber yarn is drawn by successively passing through a first roller which is not heated, a first heat treatment apparatus having a normal pressure steam atmosphere, and a second roller. As a result, the present invention has the merit of reducing the apparatus and energy costs as compared with the conventional method using the heating roller.

Since heat drawing is carried out between the first and second rollers, the draw ratio can be controlled, and the mechanical properties of any kind can be satisfied even in the production of small quantities of many kinds.

It is necessary for the fiber yarn to be one-sided so as not to circulate around the first and second rollers. This eliminates the separate roller and reduces the cost. At this time, the winding angle of the roller is preferably 150 ° or more. If it is less than 150 °, slipping on the roller is likely to occur. 170
It is more preferable to be at or above.

The surface roughness of the roller is preferably 2 S or less, more preferably 1 S or less for preventing slippage, but 0.2 S or more is preferable in view of equipment cost.

In the present invention, the take-up speed of the fiber on the first roller is 4000 m in order to improve the mechanical properties of the fiber.
/ Min is preferred, and less than 3500 m / min is more preferred. By setting the take-up speed to less than 4000 m / min, the birefringence when stretched to an appropriate elongation is 0.125.
As described above, a fiber having good mechanical properties can be obtained. The fiber take-up speed at the first roller is the second
It is determined by back-calculating from the draw ratio necessary for obtaining the yarn having the target physical properties with respect to the speed of the roller.
If it is less than 1 / minute, the productivity will decrease and the advantages of the one-step method cannot be utilized.

When the polyester fiber is unheated, that is, when it is drawn at a temperature around room temperature which is lower than the glass transition temperature, variations such as thickness unevenness in the longitudinal direction of the yarn occur, and the strength and elongation become inferior. This phenomenon can be prevented by heating and stretching the polyester fiber, but in the present invention, atmospheric pressure steam, which is cost effective for electric equipment and electric power, is used as the heating means.

The normal pressure means that the pressure in the processing chamber for heating the fiber yarn of the first heat treatment apparatus is substantially equal to the pressure outside the apparatus. This means that the total pressure in the state where the fiber does not pass through at any position in the processing chamber, that is, the sum of the static pressure and the dynamic pressure is within 10 cmH2O with respect to the external pressure. The static pressure of the pressure in the processing chamber is determined by the sealing property of the fiber yarn passage opening, which is the boundary between the processing chamber and the outside, the amount of steam introduced, the size of the processing chamber, and the like. Further, the dynamic pressure of the processing chamber can be a normal pressure by setting the introduction speed of steam to 1/4 or less of the peripheral speed of the first roller. Static pressure and dynamic pressure are obtained from a Pitot static pressure tube.

The processing chamber of the first heat treatment apparatus of the present invention is required to have a normal pressure steam atmosphere, and it is necessary to raise the temperature to more than 100.degree. When the temperature is 100 ° C. or less, the amount of drainage is increased, the heat supply to the fibers is uneven, die frecking occurs during dyeing after weaving, and the tenacity and elongation are inferior. By setting the temperature to more than 100 ° C., it is possible to reduce the generation of drainage and to prevent the fluctuation due to the atmospheric pressure. The atmospheric steam atmosphere exceeding 100 ° C. can be achieved by heating the processing chamber from the outside with pressurized steam or by setting the so-called superheat state in which the supplied steam is preheated. The processing chamber temperature is 300 to prevent abnormal stretching.
It is preferable that the temperature is not higher than ° C.

Distance L1 between the first heat treatment device and the second roller
Means the distance from the outlet of the processing chamber of the first heat treatment apparatus 6 to the contact of the fiber yarn with the second roller 7, as shown in FIG. The distance L1 between the first heat treatment device and the second roller is 0.2.
0 m or more is required. If it is less than 0.20 m, slip is likely to occur. L1 is preferably 0.3 m or more, and more preferably 0.4 m or more. The upper limit of L1 is
Considering threading workability and the like, about 1.0 m is preferable.

The peripheral length L2 of the second roller must be 0.7 m or more. If it is less than 0.7 m, slipping occurs and curling and uneven dyeing occur. L2 is preferably 1.0 m or more, more preferably 1.2 m or more. The upper limit of L2 is preferably 2.6 m or less from the viewpoint of device cost such as increasing the capacity of the power supply device for driving.

In the present invention, the stretched fiber yarn is subsequently heat-treated in order to accelerate the crystallization of the fiber. The heat treatment can be performed by a known heat treatment apparatus such as a method using the second roller as a hot roller or a hot roller, a hot plate, a hot tube, or a slit heater between the second roller and the winding, but the same as the stretching step. The use of steam is advantageous in terms of cost and is preferably used. In particular, it is preferable that the second roller is not heated, and the heat treatment is performed by sequentially passing through a second heat treatment apparatus having a pressure steam atmosphere and an unheated third roller.

The distance L1 between the first heat treatment apparatus of the present invention and the second roller and the circumferential length L2 of the second roller are such that the tension T of the yarn in the second roller is apt to cause slipping on the roller.
It is effective when the ratio T1 / T2 of 1 and the tension T2 of the yarn from the roller is large, and is particularly effective when the ratio is T4 or more. This is particularly effective when using the second heat treatment apparatus described above.

The temperature of the second heat treatment chamber of the present invention is preferably 105 ° C. or higher in order to bring the shrinkage characteristics of the obtained fiber to a practical level. The pressure in the chamber is changed according to the shrinkage ratio of the fiber to be obtained, but it is preferably in the range of 0.5 to 5 kgf / cm @ 2 in order to obtain the shrinkage ratio at a practical level.

The second heat treatment apparatus preferably employs a jacket heating method in which the processing chamber is externally heated by pressure steam or the like in order to reduce temperature fluctuation and temperature distribution in the processing chamber.

Further, in the present invention, it is preferable to simultaneously spin a plurality of fiber yarns from the viewpoint of cost advantage. The plural is
It means two or more yarns, which makes it possible to reduce the manufacturing cost. In the conventional direct spinning drawing method, since the yarn is wound around the hot roller 6 to 8 times for drawing preheating, the simultaneous 6 yarn processing is limited due to the limitation of the length of the hot roller. On the other hand, in the present invention, processing of 7 or more yarns at the same time, for example, simultaneous 8 yarns, simultaneous 12 yarns,
16 yarns can be processed at the same time, which is an extremely cost-effective drawing method.

The denier of the fiber yarn produced by the present invention is not particularly limited, but when the total denier is 20 to 250 denier and the single yarn denier is 0.1 to 30 denier, the effect of the present invention is exhibited. When the total denier is 75 denier or more and the single yarn is 3 denier or more, the effect of the present invention is particularly exerted.

The cross-sectional shape of the fiber yarn produced according to the present invention is not particularly limited, such as round, polygonal, flat, hollow, and triangular, square, multi-lobal, π, H, T type, etc. In a non-circular cross section having a small coefficient of friction, slip easily occurs, and the effect of the present invention is particularly exhibited.

An example of the direct spinning and drawing method of the polyester fiber of the present invention will be specifically described with reference to FIG. The melted polyester is discharged from the mouthpiece 1, passed through the heat retaining zone 2 under the mouthpiece, and then the chimney 3 blows cooling air to cool the yarn to a temperature not higher than the glass transition temperature, and refueling is performed by an oiling device 4. It is taken up by the first roller 5 which is not heated. The plurality of polyester fibers are taken up by the first roller 5, and subsequently, passed through the first heat treatment device 6 and the non-heated second roller 7, and at this time, according to the ratio of the peripheral speeds of the first roller 5 and the second roller 7. Stretch. Further, the fibers are heat set by the second heat treatment device 8 between the second roller 7 and the non-heated third roller 9 and, at the same time, drawn according to the ratio of the peripheral speeds of the second roller 7 and the third roller 9. The fiber further passes through the entanglement imparting device 10 and the fourth roller 11, and is wound up by the winder 12.

[0028]

EXAMPLES Each characteristic value in the examples was determined according to the following method. (A) Dyeing spots Weaving the sample as a weft thread for about 100 m to make a woven fabric, and as a dye, 95% of Diaceriton Fast Ruby 3B
2g in boiling water of 10 ℃
It was immersed for 5 minutes and dyed with stirring. After washing with water and drying, stains were evaluated according to the following criteria. ◎ and ○ are passed. (B) Curl Evaluation A sample was used as a casks wound around 5 times at a circumference of about 100 cm / circle. Grasping one end of the casks without applying a load, and observing the looseness of the casks after oscillating up and down 10 times, Converge uniformly,
Or, the case where they are aligned in parallel is marked with ◯, and the case where they are curled and wound is marked with x. The criteria of ○ are as good as the fibers obtained by the two-step method.

(C) Tension measurement Using a three-point tensiometer CHECK MASTER manufactured by Kanai Koki, the yarn tension of the running fiber yarn was measured.

Examples 1 to 5 and Comparative Examples 1 to 2 Orthochlorophenol A polyester to which 0.40% by weight of titanium oxide was added at an intrinsic viscosity [η] of 0.645 measured at 25 ° C. was melted at 290 ° C. The direct spinning / drawing apparatus shown in FIG. 1 was used to discharge from the spinneret 1 having 36 holes. After passing the discharged yarn through the 0.2 m heat retaining zone 2 under the spinneret, the yarn was passed vertically over the 1.0 m for 25 m.
The yarn was cooled by blowing air of 20 mC at m / min with a chimney 3 and oil was supplied by an oil supply device 4 installed 2.0 m below the spinneret. It was taken up by the first roller 5 having a yarn winding angle of 175 ° for 5S. Similarly, a total of 8 yarns of polyester fiber 7m
With the first roller at a yarn interval of m, the peripheral speed is 5000 m
/ Surface roughness 0.5S, yarn winding angle 17
The film was heat-stretched between the second roller 7 having a temperature of 5 ° and the temperature of the processing chamber of 110 ° C. and the first heat treatment device 6 having a length of 0.7 m. Further, the yarn passing through the second roller 7 is heated at the same peripheral speed as the second roller 7 without heating and has a surface roughness of 0.5 S and a yarn winding angle of 1 S.
Inside the 80 ° third roller 9, the yarn processing chamber inside has a processing length of 0.5 m, processing chamber temperature of 136 ° C., 2.0 kgf / cm 2
After heat-setting by the second heat treatment device 8 having the heat treatment chamber maintained at the pressure of 1, the interlace imparting device 10 and the third roller 9 are not heated at the same peripheral speed and have a surface roughness of 0.5S groove, and a yarn. After passing through the fourth roller 11 having a winding angle of 180 °,
Eight 75 denier / 36 filament polyester fibers were obtained by winding with a winder 12.
Thread tension T1 entering the second roller and thread tension T2 exiting the roller
Ratio was 17.

[Table 1] From Table 1, it was found that when L1 is 0.2 m or more and L2 is 0.7 m or more, fibers free from uneven dyeing and curling can be obtained.

Examples 6 to 7 Twelve 36 filament polyester fibers were obtained in the same manner as in Example 1 except that the denier of the obtained polyester fibers was changed.

[0032]

[Table 2] From Table 2, it was found that even if the denier was changed, a fiber free from uneven dyeing and curling could be obtained.

Example 8 The same as Example 1 except that a second roller 7 having a roller surface temperature of 160 ° C. with a heat insulating cover 14 shown in FIG. 3 was used as the second heat treatment apparatus. Eight 75 denier / 36 filament polyester fibers were obtained. The ratio of the thread tension T1 entering the second roller and the thread tension T2 exiting from the roller was 3.5.

[0034]

[Table 3] Even if the second roller is a hot roller, uneven dyeing is ◎,
It was found that a curl-free fiber was obtained.

Example 9 As the second heat treatment apparatus, a third roller 9 having a roller surface temperature of 160 ° C. with a cover 15 for heat retention shown in FIG. 4 was used, and was rotated six times through a separate roller 16. Eighty 75 denier / 36 filament polyester fibers were obtained in the same manner as in Example 1 except that heat setting was performed. The ratio of the thread tension T1 entering the second roller to the thread tension T2 exiting from the roller was 2.5.

[0036]

[Table 4] From Table 4, it was found that even if the heat setting was changed from the pressure steam treatment to the hot roller treatment, a fiber with uneven dyeing and no curl could be obtained.

[0037]

EFFECTS OF THE INVENTION By employing the method of the present invention, it is possible to produce polyester fibers at a lower cost and in a controlled draw ratio without using a hot roller and a separate roller in the direct spinning and drawing method.

[Brief description of drawings]

FIG. 1 is a schematic view showing an example of a process of high-speed spinning in a direct spinning drawing method which is generally adopted in the present invention.

FIG. 2 is a schematic diagram showing a distance L1 between a first heat treatment device and a second roller.

FIG. 3 is a schematic view showing an example of a process of high-speed yarn production by a direct spinning drawing method adopted in Example 8 of the present invention.

FIG. 4 is a schematic view showing an example of a process of high-speed yarn production by a direct spinning drawing method adopted in Example 9 of the present invention.

[Explanation of symbols]

 1: Mouth 2: Heat insulation zone under the base 3: Chimney 4: Oil supply device 5: First roller 6: First heat treatment device 7: Second roller 8: Second heat treatment device 9: Third roller 10: Entanglement imparting device 11: 4th roller 12: winder 13: processing chamber 14: heat insulation cover 15: heat insulation cover 16: separate roller

Claims (4)

[Claims] 1. A polyester fiber yarn discharged from a spinneret and cooled and solidified is drawn and heat-treated by successively passing through a first roller which is not heated, a first heat treatment apparatus having a normal pressure steam atmosphere, and a second roller. Later 3500m /
In the direct spinning and drawing method of winding at a speed of not less than a minute, the first and second rollers are one-sided, the distance L1 between the first heat treatment device and the second roller is 0.20 (m) or more, and the circumference of the second roller is A method for direct spinning and drawing a polyester fiber, wherein the length L2 is 0.7 (m) or more. 2. The heat treatment is performed by passing the second roller unheated and successively passing through the second roller, the second heat treatment apparatus having a pressure steam atmosphere, and the non-heated third roller. Item 2. A method for direct spinning and drawing a polyester fiber according to item 1. 3. The method for direct spinning and drawing polyester fibers according to claim 1 or 2, wherein seven or more polyester fiber threads discharged from the spinneret and solidified by cooling are simultaneously drawn and heat-treated. 4. A direct spinning and drawing apparatus for drawing a fiber thread by successively passing through an unheated first roller for drawing the melt-spun fiber thread, a first heat treatment apparatus having a normal pressure steam atmosphere, and a second roller. Direct spinning of polyester fiber, characterized in that the distance L1 between the first heat treatment device and the second roller is 0.20 (m) or more and the peripheral length L2 of the second roller is 0.7 (m) or more. Stretching device.