JPH07268721A - Apparatus for heat-treating polyester fiber - Google Patents

Abstract

PURPOSE:To provide an apparatus for heat-treating polyester fibers capable of simultaneously applying uniform and efficient heating and air resistance to a running yarn in a heating zone and drawing and heat-treating the polyester fibers. CONSTITUTION:This apparatus for heat-treating polyester fibers is capable of discharging a polyester polymer from a spinneret 1, once cooling and solidifying the resultant filamentous material at the glass transition temperature or below, subsequently hot drawing and heat-treating the resultant yarnlike material and then winding the obtained yarn at >=4000m/min speed. Furthermore, the apparatus comprises a rodlike yarn passage guide 3 brought from the same direction as that of cooling air and/or opposite direction thereof into contact with the filaments for narrowing the width and arranging the running filaments substantially into the yarn in a planar state under a cooling air blowoff device 2 for blowing cooling air from the direction at nearly right angles from the spun filaments (F) discharged from the spinneret and a heating unit 4 having a slitlike yarn running part and a heating zone so as to provide the longitudinal direction of the slit parallel to the plane of the running yarn just under the rodlike yarn passage guide 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat treatment apparatus for polyester fibers. More specifically, in the present invention, the spun yarn discharged from the spinneret is once cooled and solidified below the glass transition temperature, and subsequently passed through a heating zone for stretching and heat treatment to be put to practical use only in the spinning step. The present invention relates to a heat treatment apparatus capable of producing a polyester fiber having a good thread quality.

[0002]

2. Description of the Related Art Conventionally, a polyester spun yarn is once cooled and solidified below a glass transition temperature to obtain an undrawn yarn having a relatively low orientation, and then the undrawn yarn is passed through a heating zone. At the same time as heating above the glass transition temperature,
There have been proposed various heat drawing methods, heat treatment methods, and apparatuses in which drawing tension is applied by air resistance during high-speed running to draw a drawn yarn at once.

Most of these methods and apparatuses heat-treat yarns running at high speed in a heating zone uniformly and efficiently, and impart air resistance which is a drawing tension uniformly. What you gain is important, and this is the focus of your consideration.

In the above heating method or apparatus, a heating tubular body is generally used. However, in this case, since it is necessary to pass the yarn in an unfocused state without contacting the inner wall of the heating tubular body, the inner diameter of the heating tubular body or the yarn passing cross section is made relatively large. For this reason, there is a drawback that heat exchange with the yarn is poor and efficient heat application is difficult.

Further, the take-up speed becomes high, especially 4
When it exceeds 000 m / min, the accompanying flow in the yarn traveling direction becomes large. Since this accompanying flow flows into the heating zone, the ambient temperature inside the heating tubular body is lowered or becomes non-uniform, and the desired heating and drawing and heat treatment become insufficient.

In order to prevent these drawbacks, a constriction portion is provided at the inlet portion of the heating tubular body to reduce the cross-sectional area of the opening so that the inflow of the accompanying flow and the outflow of the heated gas inside the heating tubular body. Methods and devices have been proposed to prevent this.

[0007]

However, even in such a conventionally proposed method and apparatus, the accompanying flow is introduced into the heating cylindrical body and the heated gas is discharged from the inside of the heating cylindrical body. Is difficult to prevent effectively.

Therefore, there has been proposed a method and apparatus for positively injecting or sucking gas at the inlet and outlet of the yarn of the heating tubular body. For example, a method of injecting a gas of a specific temperature at a velocity in a specific range in the direction opposite to and the same as the traveling direction of the yarn at the inlet and outlet of the heating tubular body (Japanese Patent Application Laid-Open No. Hei 4 (1998)).
No. 136211), or a method in which a yarn inlet and an outlet having a cross-sectional area narrowed from the heat treatment area are provided at both ends of the heating cylinder, a heating fluid outlet is provided at the inlet, and a suction port is provided at the outlet.
No. 167909).

In the case of these methods, there is a certain effect in preventing the wake, but since the running yarn and the fluid face each other at the inlet of the heating zone, the running yarn is disturbed and the yarn is damaged. However, there are drawbacks such as deterioration of mechanical properties and sometimes fluffing of the product due to breakage of single yarn.

As a method and apparatus for imparting air resistance as stretching tension, it has been proposed that the heating zone be filled with heated gas or heated steam to be filled and pressurized. However, when imparting air resistance by these methods, it is necessary to send in a relatively large amount of gas or vapor. Therefore, a large amount of energy is consumed and the operating cost is increased.

[0011]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a heat treatment apparatus for polyester fibers which imparts uniform and efficient heating and air resistance to a running yarn at the same time in a heating zone and draws and heat treats it. It is in.

[0012]

In view of the above-mentioned present situation, the present inventors have considered the shape of the yarn running portion of the heating device and the running state of the yarn, particularly the gathered state in the heating zone and the drawing of the yarn. The present invention has been achieved as a result of extensive studies on the heat treatment effect. That is, in the present invention, a polyester polymer is discharged from a spinneret, and a yarn once cooled and solidified to a glass transition temperature or lower is subjected to heat drawing and heat treatment, and then wound up at a speed of 4000 m / min or more. In a heat treatment device for polyester fibers, a cooling air blowing device for blowing cooling air from a direction substantially perpendicular to a traveling yarn discharged from a spinneret is provided, and a cooling air blowing device is provided below the cooling air blowing device in the same direction as the cooling air and / or Alternatively, a rod-shaped yarn guiding guide for contacting the yarns from the opposite directions to bring the running yarns into alignment and arranging the traveling yarns in a substantially planar manner, and the yarn traveling portion is a slit-like portion immediately below the guide yarns, and the longitudinal direction of the slits. Is provided with a heating device having a heating zone parallel to the yarn surface on which the yarn runs, and the yarn is passed through the slit to perform heat drawing and heat treatment. The heat treatment apparatus of the polyester fiber is provided.

According to the present invention, it is possible to obtain a yarn-quality polyester fiber which can be put to practical use only in the spinning step.

The polyester referred to in the present invention mainly includes polyethylene terephthalate, but a part (usually 15 mol% or less) of the component of terephthalic acid is used as another dibasic acid component, for example, isophthalic acid, 5 It may be replaced by sulfoisophthalic acid, adipic acid, etc., or if it is partially replaced by a polyoxyalkylene glycol such as polyoxyethylene glycol. The degree of polymerization of the polyester is appropriately selected according to the type and use of the polyester. In the case of ordinary polyethylene terephthalate, the intrinsic viscosity [η] obtained from the value measured with an orthochlorophenol solution at 35 ° C. is 0.60. ~ 0.66
Is preferred.

When the polyester is melted and discharged from the spinneret, it is not necessary to use any special means, and any method can be adopted. In the present invention, however, the running yarn discharged from the spinneret is used. , The traveling yarn is substantially flat by contacting the yarn from the same direction and / or the opposite direction to the cooling air below the cooling air blowing device which blows the cooling air from the substantially perpendicular direction. A rod-shaped yarn guiding guide for arranging is provided, and after passing through the rod-shaped guide, it is guided to the heating zone.

The running state of the discharge yarns coming out of the spinneret travels substantially according to the arrangement of the spinneret discharge holes until they are converged. The discharge hole array of a normal spinneret is a circular spinneret in which discharge holes are arranged on the circumference of a single or several concentric circles at substantially equal intervals, or in parallel on the entire surface at substantially equal intervals. However, an oval or rectangular base may be used.

In any case, in the present invention, a rod-shaped yarn guiding guide is provided below the cooling air blowing device to keep the glass transition temperature or less, but the unfocused yarn is still substantially flat. Line up.

The rod-shaped thread guiding guide may be provided only in one direction from the upstream side or the downstream side of the cooling air, but it is sandwiched from both sides in order to prevent inflow of an accompanying flow and keep the thread guiding constant. It is preferable.

In the present invention, a yarn heating device is provided immediately below the rod-shaped guide. This heating device is arranged such that the yarn running portion is slit-shaped and the longitudinal direction of the slit is parallel to the running yarn face, and the yarns are arranged in a plane when passing the yarn, Further, therefore, the distance from the wall surface of the slit of the heating device to the yarn is made substantially constant for each single yarn. That is, the shape of the slit in the present invention is such that the distance from the wall surface is the same for each single yarn when the distance from the spinneret surface is the same for the running yarn, and the slit width is the yarn width. May be constant along the traveling direction of, or may be gradually narrowed. as a result,
Uniform heating is possible, uniform stretching is performed, and extremely high quality polyester fibers are stably obtained.

[0020]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a schematic view of the whole process, (a) is a front view,
(B) is a side view. 2 is a front view of a specific example of a rod-shaped thread guide which is a part of FIG. 1, and FIG. 3 is a sectional view of a specific example of a heating device which is a part of FIG.

The overall process of the present invention will be outlined with reference to FIG. The filamentous material F discharged from the spinneret 1 is once cooled to below the glass transition temperature by the cooling air A blown from the cooling air blowing device 2 in a direction substantially perpendicular to the yarn running direction. After that, the rod-shaped yarn guide 3 is pressed against the yarn F from the same direction and / or in the direction opposite to the cooling air, and is arranged in a plane and guided to the heating device 4. The heating device 4 has a slit-shaped yarn guide running portion 4a, and the slit 4a
Is arranged so that the longitudinal direction thereof is parallel to the running yarn surface.

The yarn F is heated again to the glass transition temperature or higher in the slit 4a of the heating device 4, stretched and heat-treated. Subsequently, the oil agent is applied by the oil agent applying device 5, focused by the yarn focusing guide 6, and then wound by the winding machine 9 via the transaction rollers 7, 8. In the present invention, the oil agent applying device 5 and the yarn focusing guide 6 may be an integrated type device having the functions thereof.

In the present invention, the rod-shaped yarn guide 3 is arranged below the cooling air blowing device 2 and is cooled.
Is for gathering in a plane. The thread F is cooled to a temperature below the glass transition temperature, but since it is still unfocused and before the oil agent is applied, the thread is the rod-shaped thread guide 3
It is necessary to minimize the frictional resistance caused by contact with. For this purpose, in FIG. 1, the rod-shaped yarn guiding guide 3 is arranged so as to come into contact with the yarn F from the same direction and / or a direction opposite to the cooling air A blown from the cooling air blowing device 2. The yarn F passing through the cooling zone is pushed downward in the cooling wind and bends loosely. Therefore, by aligning the rod-shaped yarn guiding guide 3 near the center of the yarn at this position, the yarn F The frictional resistance received by the rod-shaped thread guide 3 can be reduced.

The shape of the rod-shaped thread guide 3 is shown in the embodiment of FIG. As shown in FIG. 2A, one rod-shaped thread guide 3
When the yarns are pressed against each other from the upstream side of the cooling air to be gathered in a planar shape, it is preferable to provide the yarn guide 3 on the downstream side of the cooling air blowing device. On the contrary, when the yarn is pressed against the yarn guiding guide 3 from the downstream side, it is preferably provided at a position on the upstream side of the cooling air blowing device 2. As shown in FIG. 2 (b), it is preferable to use two rod-shaped guides having slits formed between them so as to sandwich the yarn from both sides.

By doing so, the frictional resistance of the yarn caused by contact with the rod-shaped yarn guiding guide can be unexpectedly reduced, and the yarns can be easily arranged in a plane, and moreover, from the cooling area. It is possible to prevent the accompanying flow brought in from flowing into the heating device.

An example of the embodiment of the heating device 4 shown in FIG. 1 is shown in FIG. In the present invention, the heating device 4 is for heating the yarn F again to the glass transition temperature or higher, and stretching and heat treatment. Slit width W of the yarn running part in the heating zone
(Note that the width that gradually narrows along the running direction (downward) of the yarn refers to the yarn ejection side width) is 15 mm or less, preferably 5 to 10 mm, the length L is 0.7 to 2 m, and the atmosphere Temperature 12
The temperature is 0 ° C or higher, preferably 150 to 220 ° C. If the slit width W is larger than 15 mm, a large amount of energy is required to maintain the ambient temperature in the slit, which is not preferable. Further, when the slit width is too small, it can be said that the threaded objects to be passed through are gathered in a flat shape, but positioning is difficult, and the difference in heat application becomes large when the thread is displaced from the center of the slit, It becomes difficult to perform uniform drawing and heat treatment, and sometimes fusion between filament yarns and yarn breakage easily occur.

The length L of the heating region varies depending on the slit width and the set temperature, but the optimum length is 0.
It is preferably 7 to 2 m. If the length is less than 0.7 m, the yarn will be 400
When operating at a take-up speed of 0 m / min or more, the passage time is about 0.01 seconds, the heat received from the heating device is insufficient, and uniform stretching cannot be performed.

However, when the length L exceeds 2 m, 400
At 0 m / min or more, and particularly at 5000 m / min or more, in a single yarn 1 to 5 denier yarn for general clothing, the air resistance of the yarn in the slit is larger than necessary relative to the yield stress of the yarn required for stretching. As a result, the tension becomes unstable and uniform yarn cannot be obtained. The length of the heating zone needs to be appropriately selected together with the take-up speed depending on the single yarn denier of the target yarn.
0.7 to 2 m with normal polyester fiber of 5 de / fil
Is preferred.

The heating device 4 according to the present invention is used in combination with the rod-shaped yarn guide 3 to make the heating zone into a slit shape and only heat from both sides to provide a narrowed portion at the inlet or outlet of the heating zone or to apply pressure. It is characterized in that the yarn can be easily stretched and heat-treated without the need to positively blow the fluid into a pressurized state.

In the present invention, the reason why the air resistance necessary for stretching is imparted in the heating zone without positively applying the pressure to the heating zone is that the distance from the wall surface of the heating element is the same for each yarn. It is considered that this is because the yarn is almost the same, which makes it possible to keep the distance short and increase the air resistance. Since this effect and the distance from the wall surface of the heating body are almost the same for each single yarn, uniform heating is possible, and uniform stretching is performed and extremely stable high quality polyester fibers can be obtained. .

Another effect of the heat treatment apparatus of the present invention is that threading into the heating zone becomes easy. When the heating device has a cylindrical shape, a method of inserting a yarn bundle from the inlet of the yarn guide and sucking it with an aspirator from the outlet may be used.However, in the heat treatment device of the present invention, the gathering portion of the yarn bundle is rod-shaped. Since the yarn guide and the heating device are slit-shaped, such a procedure is not necessary and the insertion can be easily performed from the opening side of the slit.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0033]

Example 1 The intrinsic viscosity [η] determined from the value measured at a temperature of 35 ° C. in an orthochlorophenol solution was 0.64.
No. 0 polyethylene terephthalate (melting point 260 ° C., glass transition temperature 68 ° C.) was directly spun and drawn using the apparatus shown in FIG.

A spinneret having 36 holes and spinning holes with a hole diameter of 0.27 mm was used, and the fineness of the obtained drawn yarn was 7
Melt spinning was performed at a spinning temperature of 290 ° C. with a polymer discharge amount that was constant at 5 de / 36 fil, and a side blowing type cooling air blowing device was used to cool the spun yarn, at a temperature of 26 ° C. and a humidity of 65R.
The cooling air adjusted to H% was blown at a speed of 0.4 m / sec at a speed of 0.4 m / sec from a position 12 cm directly under the spinneret to a length of 100 cm at right angles to the spun yarn, and the temperature of the yarn was changed to a glass transition. Cooled below temperature.

Then, the cooled yarns are pressed against the yarns in the same direction and opposite directions as the cooling air by using two rod-shaped yarn guide guides made of alumina having a diameter of 4 mm so that the traveling yarns are moved. After arranging them in a substantially planar shape, they were introduced into the heating device shown in FIG. 3 and subjected to a stretching heat treatment, and then the oil agent-applied yarns were bundled and wound up via a take-up roller.

Here, the heating device has a slit width of 8 mm and a length of 1.5 m, and the upper end position of the heating area is 1.6 m below the spinneret.
In addition, the yarn focusing guide position after applying the oil agent was fixed to the position of 3.3 m, the temperature setting of the heating region and the yarn take-up speed were changed, and the results in Table 1 were obtained.

[0037]

[Table 1] Regarding the strength and elongation characteristics of the obtained yarn, the breaking strength is 4 g.
If it is / d or more and the elongation is 50% or less, it can be said that the yarn can be used for general clothing applications. In the dye spot test, the yarn is knitted into a tubular knit and then dyed (dye: Eastmann Polye
ster Blue, owf 2% at 100 ° C. for 90 minutes), and the test knitted fabric was visually judged. The one with no spots was grade 5, and the one with spots was 0 as the degree increased.
Grades up to grade 1 on the grade 5 pitch, grades 3 and above were acceptable, and grades below that were unusable for practical use.

In Table 1, those belonging to the present invention (No 1
~ 5, 9, 10, 12, 13) has strength, elongation and boiling water shrinkage in an appropriate range for general clothing, and the dyeing spot which is an important characteristic for clothing use is grade 3 or higher, Although it can be sufficiently put to practical use, it does not belong to the present invention (No.
Nos. 6 to 8, 11, and 14) have too large an elongation and cannot be put to practical use as they are. In addition, No. 7, 11, and 14 did not use a heating device for comparison, and when the temperature of the region corresponding to the heating region was set to room temperature (RT), stretching did not occur and the elongation remained. Further, it is clear that No. 8 has a low heating region temperature, and No. 6 is too high on the contrary, and uniform dyeing and heat treatment are not performed, resulting in poor spotting and no practical value.

[0039]

[Example 2] Under the spinning conditions of Example 1, the length of the heating zone of the heating device and the slit shape were variously changed and Table 2
Got the result.

The heating zone temperature was set to 200 ° C. and the yarn take-up speed was set to 4500 m / min. In addition, the upper end position of the heating area is located 1.6 m below the spinneret, and the yarn focusing guide positions are 3.7 m for Experiment Nos. 18 and 19, respectively.
The length was 4.1 m, and the others were fixed at the same 3.3 m position as in Example 1.

[0041]

[Table 2] As is clear from Table 2, among those in which the length of the heating zone was changed (Nos. 15 to 19), Experiment No. 15 also belongs to the present invention, and the strength and elongation characteristics are in a range suitable for clothing use, It is near the limit in the third grade of spots, and the heating area is 0.7 m
It can be seen that if the value is less than the value, heat will be insufficient.

On the other hand, in the case of Experiment No. 19, fine stains are beginning to appear, which is caused by the yarn swaying in the heating area due to the lengthening of the yarn focusing guide position, which is 2.5 m or more. Indicates that it is not preferable.

In Experiment Nos. 20 to 23, slits having a shape gradually narrowed along the running direction (downward) of the yarn were used. The same yarn input side / outlet side (No
Compared with 17), N is narrowed except that the effect of increasing the tension gradient in the heating region can be seen by preventing the heated air from flowing out in the heating region by narrowing the slit outlet side.
Satisfactory results were obtained as in o17.

[0044]

According to the present invention, there is provided a heat treatment device for polyester fibers, in which uniform and efficient heating and air resistance are simultaneously applied to a running yarn in a heating zone, and which is drawn and heat treated.

[Brief description of drawings]

FIG. 1 is a schematic view of the entire process, in which (a) is a front view and (b) is a side view.

FIG. 2 is a front view of a specific example of a rod-shaped thread guide which is a part of FIG.

FIG. 3 is a cross-sectional view of a specific example of a heating device that is part of FIG.

[Explanation of symbols]

 1 Spinneret 2 Cooling Air Blowing Device 3 Rod-shaped Thread Guide 4 Heating Device 5 Lubricant Applying Device 6 Yarn Focusing Guide 7 Take-up Roller 8 Take-up Roller 9 Winding Machine F Spinning Yarn A Cooling Wind

Claims (1)

[Claims] 1. A polyester polymer is discharged from a spinneret, a filament once cooled and solidified to a glass transition temperature or lower is subjected to heat drawing and heat treatment, and then heat treatment of polyester fiber wound at a speed of 4000 m / min or more. In the device, a cooling air blowing device for blowing cooling air from a direction substantially perpendicular to the spun yarn discharged from the spinneret is provided, and the cooling air blowing device is provided below the cooling air blowing device in the same direction and / or opposite to the cooling air. The rod-shaped yarn guide for arranging the yarns in contact with the yarns from the direction so that the yarns run substantially parallel to each other, and the yarn running portion has a slit-like shape immediately below the guide, and the longitudinal direction of the slits runs. A heating device having a heating zone that is parallel to the yarn surface to be heated is provided, and the yarn is passed through the slit for heating and drawing and heat treatment. Reester fiber heat treatment equipment.