JPS59106509A - Manufacture of fiber having latent bulkiness - Google Patents

Abstract

PURPOSE:To manufacture the titled fiber having high bulkiness, in high productivity, by forcing plural streams of a molten polymer to collide with each other and oscillate under the sprinneret to form a single stream, passing the stream successively through a high-temperature region under the sprinneret and having a specific temperature range, a region sprayed with a liquid and a cooling region, and winding the solidified stream. CONSTITUTION:A melt-sprinnable polymer (e.g. polyethylene terephthalate) is melted, extruded through a sprinneret and solified. In the above process, two or more streams of the molten polymer is forced to collide with each other and to oscillate under the spinneret to form a single stream, and the stream is passed successively through (a) a region having an ambient temperature of 100-300 deg.C and extended from the surface of the spinneret to at least 10cm below the surface, (b) a region sprayed with a liquid such as water, and (c) a cooling region to effect the solidification, and wound to obtain the objective fiber. The winding speed is preferably 3,500-5,000m/min.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improved method for producing polyester fibers, and more particularly to a method for producing polyester fibers that can be wound at high speed, have significantly improved bulk properties, and have nine latent bulk properties.

Conventionally, in the method of obtaining bulky yarn, the spinning speed is at most i s
It has been well known for a long time that undrawn yarn spun at a low speed of about 0.0 m/m is drawn and finally subjected to false twisting. In this case, although the processed yarn is stable in terms of quality, the number of steps required to obtain bulky yarn is large, requiring more manufacturing equipment and workers, and the spinning speed and power loe speed are low. The major disadvantages are that productivity is low, and since the undrawn yarn is wound up at a low spinning speed, the undrawn yarn changes rapidly over time, so sufficient consideration must be given to air conditioning equipment.

Therefore, as a method to eliminate the above-mentioned drawbacks, recently, undrawn yarn (usually POY) that is wound at a spinning speed of 3000 to 3500 m
The main manufacturing method is to perform stretching and false-twisting at the same time, and the stretching and false-twisting speed is also 500 to 600 m/am.
The speed is increasing. On the other hand, various studies are being conducted on sb, which is a production method in which the spinning process and drawing/false twisting process are separated, and so-called 5DTY, which integrates these processes. The only problem with these methods is that the bulkiness is imparted mechanically, so the winding speed is 3
It remains within 500,,/=.

On the other hand, various studies have begun to be conducted on techniques for directly producing textured filaments at a spinning speed of 350 G@/am or higher.

Many methods for directly obtaining textured filaments at spinning speeds of 3500 m/- or higher utilize bulkiness (crimp) caused by differential shrinkage in fiber filaments. As a specific method, for example,
Spinning two streams of polyester through a single spinneret, as described in Publication No. 42115, etc.
A method is described in which these two streams collide and vibrate under the mouthpiece, and then are rapidly cooled and rolled up.

Furthermore, many methods have been proposed for varying the speeds of the two colliding and vibrating flows. According to these methods, the occurrence of this crimp is controlled only by the collision and vibration of the two polymer flows, so the accuracy of the die becomes a major problem in order to obtain a uniform ring. For example, it goes without saying that careful consideration must be taken when making the nozzle, but if the nozzle is used an increased number of times, the nozzle will wear out and many troubles will occur during spinning. Also, regarding the crimp level,
Compared to those obtained by conventional methods, the bulkiness was not satisfactory, and there remained room for further improvement.

Therefore, the inventors of the present invention have made extensive studies to eliminate the shortcomings in the paper, and have found that the generation of rings is not only a kinetic energy pseudo tree due to collisions and vibrations of polymer flows, but also when collisions and vibrations occur. It has been learned that the ambient temperature surrounding the above two streams and the ambient temperature at which the 1-'' stream is formed and solidified are extremely important.

However, it is extremely cumbersome in manufacturing to check each time the atmospheric temperature when two polymer streams collide and vibrate, and the atmospheric temperature until a single polymer stream is formed and solidified. Not practical. Therefore, as a result of further investigation, we found that the above problems can be largely solved by measuring and controlling the atmospheric temperature up to 103 points at least when the mouthpiece is lowered, and that the flow after collision and vibration can be solidified. In the previous process, we found that the talimp level could be dramatically improved if a rapid cooling or anisotropic cooling process was introduced.

That is, the present invention melts a melt-spun polymer,
When solidifying by discharging from the spinneret, two or more streams of molten polymer are collided and vibrated under the spinneret to form a single stream, which is then directed at least 10 meters below the spinneret surface. A method for producing a latent bulky fiber, which comprises passing through an area where the ambient temperature is 100 to 300°C, then passing through an area where a liquid has been sprayed, and then passing through a cooling area to solidify and wind up the fiber. It is.

The melt-spun polymer targeted in the present invention is:
Polyethylene terephthalate, in which 85 moles or more of the repeating units are substantially composed of ethylene terephthalate, and the polymer contains additives for matting, improving dyeability, antistatic properties, etc. as a copolymer or blend. There is no problem even if there is. The intrinsic viscosity of polyethylene terephthalate (measured in orthochlorophenol at 35°C) is 0.
45 to 1.20 is preferable, and 0.50 to 1.00 is particularly preferable. When the intrinsic viscosity is less than 0.45, the strength level of the resulting fiber is undesirably low. In addition, the ultimate viscosity
When the degree exceeds 1.20, the melt viscosity during spinning becomes too high and it is necessary to raise the melting temperature, which is not preferable.

The purpose of converting the melted polymer into two streams is then achieved by branching the melt in a conventionally known mouthpiece. Then, the branched molten material may be pushed out through an opposing die, and the branched molten material may be caused to collide and vibrate under the die. The collision/vibration conditions are also adjusted by known methods, for example, by adjusting the hole diameter, land length, and opposing angle of the opposing die through which the branched melt is extruded. Similarly, this collision/vibration can also be achieved by varying the discharge speed ratio of the branched molten material from the mouth surface.

Furthermore, the purpose of adjusting the ambient temperature surrounding the flow during collisions and vibrations can be achieved by installing a heating tube between the bottom of the mouthpiece and the cooling area. The heating tube does not require any particular improvement over conventional equipment; for example, a system for heating spun yarn used in tire cord manufacturing is sufficient. The length of the heating cylinder may be in the range of 5 to 40 cIn. If the length of the heating tube itself is 5 crn and is not grooved, the length of the heating tube is too short and it is difficult to maintain the ambient temperature under the nozzle at the desired level, and the denier of the constituent filaments in the resulting fiber is too short. Assuming that it is uniform, also,
The difference in shrinkage between filaments is also extremely small. On the other hand, the length of the heating cylinder is 40c! Even if it exceeds n, no improvement in the effect of extending the heating length is necessarily observed, and the equipment becomes larger, so that no particular advantage is seen. Next, regarding the ambient temperature, set the ambient temperature from the mouth surface to at least 10 (7) below.
It is necessary to maintain the temperature in the range H of 00 to 300°C. If the ambient temperature is less than 100° C., the ambient temperature is too low and a highly useful ring cannot be obtained unless the difference in denier or shrinkage between the filaments constituting the resulting fiber is small. On the other hand, if the ambient temperature exceeds 300°C, the temperature of the metal tube becomes extremely high due to heating.
Two or more polymer streams come into contact with the nozzle surface, which stains the nozzle surface and easily causes single fiber breakage.In addition, the cooling rate becomes extremely slow, causing fluff and yarn breakage due to yarn shaking, which is not preferable. .

The polymer stream, which has passed through a region with an ambient temperature of 100 DEG to 300 DEG C., is then passed through a region where the liquid has been sprayed before assimilation. Water is sufficient as the liquid component, and if various functions are to be imparted, a liquid other than the water mass may be sprayed. In the case of this spraying, for example, if the liquid component is water, heated steam or steam generated by ultrasonic vibrations can accomplish the purpose. In addition, the spray area is 15 to 50 mm below the nozzle.
It is appropriate to install it with a spread 9 of 10 to 20 cIn in the LM area. Liquid sprays. If the bottom 15 crn of the cap is not grooved, the area near the cap surface will be cooled by the sprayed liquid, resulting in breakage of single fibers, which is not preferable. On the other hand, if the yarn is installed in an area exceeding 50 parts below the mouthpiece, the temperature of the yarn is quite low, so that the rapid cooling and anisotropic cooling effects due to spraying will not occur.

It should be noted that although it is a liquid application, it is better to apply it in a liquid form or in a spray form. If this is applied in liquid form,
If the area is not over 50m below the nozzle, thread breakage will occur frequently.
This is because it cannot be applied as a manufacturing condition.

Furthermore, if the temperature exceeds 50 crn under the nozzle, the yarn temperature may be significantly lowered, so that a sufficient effect may not be obtained. When applied in the form of a spray, the above-mentioned drawbacks are overcome and it is extremely useful.

Finally, the yarn passed through the area where the liquid was sprayed is solidified in the same manner as in normal spinning. For example, with air at a temperature of 26°C and humidity of 65%, the air volume is 3 with a side-blown spinning tube.
It is solidified under the condition of 1'J y//sm, and after applying oil with an oiling roller, it is rolled up.

The winding speed is 3500 m/s.o.
A range of o o m/- is preferable. Winding speed 35
If the spinning speed is less than 00 m/wR, fibers with sufficiently satisfactory mechanical properties cannot be obtained because the spinning speed is low, whereas when the spinning speed exceeds 5000 m/wR, oriented crystallization progresses. It is difficult to obtain a highly useful ring.

According to the present invention, when two or more flows are collided and vibrated to form a single polymer flow, the ambient temperature before and after the collision and vibration is heated to a temperature range that falls within the temperature range, and then A highly useful ring can be obtained very easily if the polymer stream is passed through a liquid sprayed area before solidification and then rolled up after being subjected to a quenching and anisotropic cooling process.

The reason for this is the collision of two or more polymer streams.
If the ambient temperature surrounding the flow during vibration is within a certain temperature range, a sufficient shrinkage difference can be observed between the filaments that make up the resulting fibers, and the flow after collision and vibration can also shrink before it solidifies. It is thought that by passing the liquid through the sprayed area, rapid cooling and anisotropic cooling effects are added, and the cling level is synergistically improved.

When the liquid is in the form of a spray, the polymer flow can be applied at a higher temperature than when the liquid is in the form of a spray, so the effect is greater.

Furthermore, since the liquid is in the form of a spray, it is possible to microscopically cool the yarn, and since the running yarn is not shaken, the spinning property is also good.

As described above, the present invention provides a polyester fiber that can be wound at high speed, has highly useful rings, and has significantly improved mechanical properties. Moreover, in manufacturing such fibers, the generation of cling does not depend solely on the precision of the die, and the form of the heated area and the area where the liquid is sprayed is simple in terms of equipment and can have a sufficiently large effect. In view of the fact that it is possible to obtain a textured filament and the ease of control during production, the following method is used to directly produce textured filaments at a spinning speed of 3500 m/- or more.
Its industrial value is extremely high.

Hereinafter, the present invention will be explained in detail by referring to Examples. In this example, bulkiness was evaluated using crimp/yield rate. In addition, the mechanical properties were evaluated based on the strength and elongation of the obtained fibers and the primary yield stress. The measurement method for each item is as follows.

Furthermore, (I) crimp and shrinkage rate are determined by the following method. Make a 1500 denier ``skein'' from the sample.

Apply a load of 100++y/de to this skein, and then assume that the length of skein J is 10.Then, 1O0tq/
Remove the load of d e, apply a load of 2.5 sv/de, and process for 5 minutes in a dryer maintained at 120°C. After leaving the treated U-skein in the air for 5 minutes,
Find the length of. This value is the stone. Next 2.5q/d
Remove the load e, apply a load of 100 +y/de, and let the length at this time be t2. Crimp these values into the following formula.

The shrinkage rate was calculated.

Crimp (%) = two anus x 100 2 Shrinkage rate (%) = to-t2X 100 t.

(II) Strength was measured using a constant-speed extension type tensile tester.
Initial load 1/309/de, sample length 100.20°C.

It is the value obtained by dividing the breaking strength determined under the conditions of an elongation rate of 200 ml/m in an atmosphere of 65% RH by the denier of the sample. (The elongation indicates the breaking elongation of the sample under the above conditions.
CF/) Primary yield stress corresponds to the modulus and degree of orientation of the fiber, and is the value obtained by dividing the initial yield strength observed in the load-elongation curve when measuring strength and elongation by the denier of the sample. Example 1 Polyethylene terephthalate (containing 0.5% TlO2 as a matting agent) with an intrinsic viscosity of 0.64 was melted and the flow was branched in a spinneret, one having a pore diameter of 0.20 m.
+ Land length is 0.60. round hole, the other has a hole diameter of 0.35
+a+sy land length 3. Ou's round hole and pl each 5°
It was pushed out with opposing angles of , and collided and vibrated under the mouthpiece. A heating tube with a length of 15 mm is installed under the base.
A temperature detection end was inserted into the heating cylinder at a point 10 tM below the nozzle, and the atmospheric temperature threshold at a point 10 tM below the nozzle was detected.

Furthermore, below the heating cylinder, at a point 20 cm below the base,
Water particles generated by a commercially available ultrasonic humidifier are
Sprayed over ~206n. In addition, the spray amount is 4 in terms of water.
It was 00cc/hr. The yarn consisting of 72 yarns that has passed through the heating area and spraying area is passed through the spinneret into 6
The fibers were cooled and solidified in a cross-blowing spinning tube with a length of 80 eM installed below zero, and then an oil was applied with an oiling roller and then rolled up to obtain fibers of 160 de/72 f. Similarly, during winding, the temperature inside the heating cylinder was variously changed, and the presence or absence of spraying of water particles by turning the humidifier switch ON and OFF, and the winding speed were variously changed during winding. The results of measuring the bulkiness and mechanical performance of the obtained fibers are shown in the table below.

Table I Spraying water particles and increasing the temperature inside the heating cylinder each have an effective effect on improving crimp. When both are used in combination, the effect is doubled, the crimp level is significantly improved, and it has been possible to obtain highly useful rings even at high spinning speeds of 4,500 yl/l il+ or higher.

Similarly, when the spinning speed exceeds 5000 m/mr, the oriented crystals progress, and a highly useful ring could not be obtained.

Comparative Example 1 The heating cylinder temperature was set at 340°C and water particles were sprayed, and the spinning speed was 4500 in the same manner as in Example 1.
Although winding was performed at a speed of m/m, the spinning condition was extremely poor, and yarn breakage due to single fiber breakage occurred frequently.

In addition, the obtained fibers contained fluff, which was not preferable.

Comparative Example 2 The heating cylinder temperature was set at 250°C and water particles were sprayed, and the spinning speed was 3300 m in the same manner as in Example 1.
I turned it over with /-. The obtained fiber had low mechanical properties, with an elongation of 130% and a strength of 2.2 f/de.
It could not be put to practical use as it was.

Patent applicant Teijin Ltd.

Claims (4)

[Claims] (1) When a melt-spun polymer is melted and solidified by being discharged through a spinneret, two or more streams of molten polymer are collided and vibrated under the spinneret to form a single stream. This is then passed through an area where the ambient temperature is 100 to 300°C at least 10 degrees below the mouth surface, and then passed through an area where the liquid has been sprayed, and then passed through a cooling area to solidify. A method for producing a latent bulky fiber characterized by staking and rolling. (2) Winding speed is 3500-5000m/Mi
The manufacturing method according to claim 1, wherein R is R. (3) The manufacturing method according to claim 1, wherein the melt-spun polymer is polyester. (4) Claim 1 in which the liquid component is water
Manufacturing method described in section.