JP3236211B2 - False twisted yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a false twisted yarn having good drapability and resilience and exhibiting a spun-like feel and appearance.

[0002]

2. Description of the Related Art Hitherto, a method of producing a bulky yarn by simultaneously drawing and twisting undrawn polyester yarn has been widely used.

[0003] At this time, a method of heating the yarn in the twisted region to a temperature of about 200 ° C, performing drawing and heat setting, and then untwisting has long been adopted. When the false-twisted yarn is made of a fabric, there is a problem in that crimps are developed and shrinkage occurs in subsequent steps such as relaxation, presetting, weight reduction, and dyeing, and the drapeability and resilience of the fabric are reduced.

[0004] In order to solve such a problem, a so-called two-stage heater false twisting method in which the above-described false twisting is performed, and then a heating set is further performed using a heating heater plate, is used. However, when a high-temperature final setting or the like is performed, shrinkage occurs again, and there is a problem that the drapability and resilience of the fabric are reduced.

On the other hand, Japanese Patent Publication No. 1-60568 or Japanese Patent Publication No. 47050/1992 discloses that a polyester undrawn yarn is false-twisted at a low temperature. Not only can it not be imparted, but also the drape and rebound of the fabric due to shrinkage decrease more remarkably.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a false twist processing which solves the above-mentioned problems of the prior art, has good drapability and repulsion, and has a spun-like feel and appearance. To provide yarn.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object, and as a result, the polyester undrawn yarn was heated in a non-twisted state by contacting it with a heating body at 70 to 140 ° C. Thereafter, it was determined that the above-mentioned object can be achieved when simultaneous drawing false twisting is performed using the heating end point as the twisting start point.

Thus, according to the present invention, the polyester undrawn yarn is heated in a non-twisted state by contacting it with a heating body at 70 to 140 ° C. Twisted false twisted yarn, there is a variation in crimp between the single fibers constituting the false twisted yarn,
A false twisted yarn is provided, wherein the peak temperature of the thermal stress of the false twisted yarn is 170 ° C. or lower.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The false twisted yarn of the present invention is obtained by heating an unstretched polyester yarn in a non-twisted state to 70 to 140 ° C., and then performing simultaneous draw false twisting with the heating end point as a twisting start point. , Can be easily manufactured.

More specifically, simultaneous stretching false twisting may be performed using a stretching false twisting apparatus as shown in FIG.

That is, the polyester undrawn yarn 1 is
It is wound around the heating roller 3 a plurality of times via the supply roller 2 and heated to 70 to 140 ° C. in a non-twisted state.

When the heating temperature is lower than 70 ° C., uneven drawing occurs, and the peak temperature of the thermal stress of the obtained false twisted yarn exceeds 170 ° C. On the other hand, the heating temperature is 140 ° C
If it exceeds, flow stretching will be carried out, and long-period spots will be generated, and variations in crimp will be reduced, making it impossible to impart a span-like feel and appearance.

The number of windings on the heating roller may be appropriately set in accordance with the desired amount of heat. However, in order to prevent the yarn from slipping, it is preferable to wind four or more windings.

Next, while the yarn release point of the heating roller 3 is pressed by the pressing roller 4, a false twisting tool (false twisting disk)
5, twisting and untwisting, and winding and drawing a plurality of times around a drawing roller 6 rotating at a higher peripheral speed than the heating roller 3, thereby cooling the undrawn yarn without cooling the undrawn yarn. (Thread release point of heating roller 3)
Stretching is performed simultaneously with false twisting in a state where the false twist is retroactively performed.

Conventionally known false twisting devices such as a pin type and a triaxial friction type disk type can be arbitrarily employed. However, a triaxial friction type disk type false twisting device capable of increasing the false twisting speed can be used. preferable.

It is preferable that the yarn after the drawing false twist is wound around a pan 8 by a spindle-type winding device 7. That is, when the processed yarn having the variation in crimp is wound as cheese, when supplying to the weft of a twisting step or a water jet loom, it was necessary to rewind to improve the de-spreading property, When a spindle-type winding device is used, it can be supplied to a twisting process or a loom as it is, so that there is an advantage that a rewinding process is not required.

As shown in FIG. 2A, there is a variation in crimp between the single fibers constituting the false twisted yarn obtained by the above method. Low crimped single fiber b is mixed.

Here, the variation in the crimp may be any value that can impart a spun-like feel and appearance to the fabric in combination with the yarn length difference. The difference from the number of crimps is preferably 5 / cm or more.
More preferably, the number is 0 / cm or more.

The minimum number of crimps includes the number of crimps (less than 1 piece / cm) of a flat single fiber having substantially no crimp.

That is, in the present invention, the unstretched yarn 1 is spread on the heating roller 3 and spreads flat, so that each single fiber is separated from the yarn at the pressing point of the pressing roller 4. The fiber is fixed to the fiber located at the center and the fiber located at the end, and is stretched and false-twisted, so that a tension difference occurs between the single fibers.

Then, in the twisting area after leaving the press roller, the single fiber having a high tension is placed at the center of the yarn,
The single fibers having a low tension move so as to be arranged at the end of the yarn, and a difference in yarn length occurs due to a difference in elongation between the single fibers, and the crimp applied to each single fiber varies. Occurs.

In particular, when there are untwisted twists or spots of oil on the undrawn yarn, the state of opening of the yarn is randomized,
The above phenomenon is remarkably exhibited.

On the other hand, in the conventional false twisting process, the supply yarn is supplied to the twisting region without being spread, and is stretched and heat-set in a state where the yarn is further bundled by twisting. Only a uniform crimp as shown in FIG.

Further, the peak temperature of the thermal stress of the false twisted yarn of the present invention must be 170 ° C. or less,
More preferably, the temperature is 0 ° C. or lower.

FIG. 3 shows a heat shrinkage stress curve of the false twisted yarn, wherein a is a conventional single-stage heater false twisted yarn, b is a conventional two-stage heater false twisted yarn, and c is a main twisted yarn. 1 represents a false twisted yarn of the invention.

In the conventional false twisted yarn, as shown in FIG. 3A, the heat shrinkage stress increases as the temperature increases. Therefore,
In the case where such a false twisted yarn is used as a fabric, shrinkage increases in subsequent steps such as relaxation, presetting, weight reduction and dyeing, and also in final setting, and the drape property and resilience of the fabric decrease.

Further, the false twisted yarn of the further two-stage heater false twisted yarn which has been subjected to heat set, as shown in b of FIG. 3, has a minimum value of heat shrinkage stress in the vicinity 0.99 ° C., Steps such as relaxing, presetting, weight loss and dyeing do not cause much shrinkage, but at higher temperatures (e.g. 180
C.), shrinkage occurs again, and the drapeability and resilience of the fabric are reduced.

On the other hand, the false twisted yarn of the present invention has a heat shrinkage stress peak temperature of 170 ° C. as shown in FIG.
In the following steps, the shrinkage force is reduced in the steps after the relaxation, the preset, the weight reduction, and the dyeing, and the binding force of the yarn in the fabric is not increased, so that the drapability and the resilience are maintained.

Thus, the reason why the false twisted yarn of the present invention shows a unique heat shrinkage stress curve as compared with the conventional false twisted yarn is as follows.
Since the undrawn (low orientation) yarn is heated in a state where the yarn is opened, it is considered that a sufficient amount of heat is given to the constituent single fibers and a stable fiber structure is formed. Can be

In the above method, when the amount of heat for heating by the heating roller is insufficient, a plurality of heating rollers may be used, and a heating heater plate or a heating gas generating means may be provided downstream of the heating roller as an auxiliary heating means. Any method such as a method of providing a device can be adopted.

[0032]

Since there are variations in the crimp between the single fibers constituting the false twisted yarn of the present invention, when the fabric is used, the difference in the crimped form and the difference in the length of the yarn become apparent, and the spun like yarn is produced. It can give a good feeling and appearance.

In the false twisted yarn of the present invention, since the peak value of the heat shrinkage stress is 170 ° C. or less, the shrinkage force decreases as the temperature rises, and the binding force of the yarn in the fabric decreases. Since the fibers do not become strong, the inter-fiber voids are maintained, exhibiting good drapability, and the rebound resilience resulting from the above-described crimped form difference and yarn length difference is maintained even after heat treatment.

[0034]

The present invention will be described more specifically with reference to the following examples. In addition, each physical property in an Example was measured by the following method.

(1) Number of crimps A single fiber having a length of 10 cm is randomly selected from the false twisted yarn.
This sample was taken, a load of 0.002 g / denier was applied, and the number of crimps per cm was measured under a microscope.
The value of / 2 was taken as the number of crimps.

(2) Heat Shrinkage Stress Using a heat shrinkage stress measurement device (type KE-2S) manufactured by Kanebo Engineering, a sample was formed into a loop having a length of 10 cm, and the temperature was increased at a rate of 2.3 ° C./sec. -The heat shrinkage stress curve was recorded on the chart.

The above measurement was repeated three times, and the peak temperature of the heat shrinkage stress was read from the chart, and the average value was taken as the peak temperature of the heat shrinkage stress.

(3) Hand feeling of woven fabric The drape property and repellency of the woven fabric, and the spun like hand feeling and appearance were sensory evaluated by five skilled workers. The evaluation was ◎ (very good), ○ (good), Δ (somewhat poor), ×
The evaluation was made in four stages of (poor).

[Examples 1-3, Comparative Examples 1-2] Unstretched polyethylene terephthalate yarn (450 denier / 72 filaments) spun at a spinning speed of 1300 m / min using a false twisting device shown in FIG. Under the conditions shown in No. 1, stretching simultaneous false twisting was performed.

A triaxial friction type disk type false twist device was used as the false twist device, and the peripheral speed of the disk was 600 m / min.

A vertical spindle type winding device was used as the winding device, and the spindle rotation speed was set to 4500 times / minute.

Table 2 shows the difference between the maximum crimp number and the minimum crimp number of the single fiber constituting the obtained false twisted yarn, and the peak temperature of the heat shrinkage stress.

Next, the false-twisted yarn was laid out on a warp and a weft without twisting, woven into a plain woven fabric, and then relaxed, preset, reduced in weight, dyed, and subjected to fianal setting in a conventional manner.

The weight loss was determined using a caustic soda solution and the weight loss rate was set to 15%.

Table 2 also shows the feeling of the obtained woven fabric.

[0046]

[Table 1]

[0047]

[Table 2]

[Comparative Example 3] The same unstretched polyethylene terephthalate yarn (450 denier / 72 filaments) as in Example 1 was heated and drawn 2.95 times by a conventional method.
A drawn yarn of 53 denier / 72 filaments was obtained.

The drawn yarn was heated using a conventional false twisting device shown in FIG.
00r. p. m. False twisting was performed at a processing speed of 120 m / min . Textured yarn obtained has a heat-shrinkage stress curves shown in a in FIG. 3, the peak temperature was 235 ° C..

Further, the single fibers constituting the false twisted yarn were uniformly crimped, and there was no variation in the crimp and no difference in yarn length between the single fibers.

Further, using the same method as in Example 1, a woven fabric was obtained from the false twisted yarn. The woven fabric lacked drapeability and repulsion, and had a far from spun-like appearance and feeling. Was.

Comparative Example 4 The same untwisted polyethylene terephthalate yarn (450 denier / 72 filaments) as in Example 1 was heated using a conventional false twisting apparatus shown in FIG. An attempt was made to perform simultaneous false twisting at 85 times, a spindle rotation speed of 2400 rpm, and a processing speed of 120 m / min. However, yarn breakage frequently occurred on a heater, and no false twisted yarn was obtained.

Comparative Example 5 The same operation was performed as in Comparative Example 4, except that the heater temperature was changed to 100 ° C.

[0054] textured yarn obtained has a heat-shrinkage stress curves shown in a in FIG. 3, the peak temperature was 250 ° C..

Further, the single fibers constituting the false twisted yarn are hardly crimped, and the single fibers constituting the processed yarn have a variation in crimp and a difference in yarn length. Did not.

Further, when a woven fabric was obtained from the false twisted yarn using the same method as in Example 1, the woven fabric had band-like stained spots, and it was impossible to put it on the market as a product. there were.

[0057]

According to the present invention, it is possible to provide a false twisted yarn having good drapability and resilience and exhibiting a spun-like feel and appearance, and can be suitably used for clothing and the like.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of a false twist device of the present invention.

FIG. 2 is a side view showing a crimped form of the false twisted yarn of the present invention and a conventional false twisted yarn.

FIG. 3 is a schematic diagram showing a heat shrinkage stress curve of a false twisted yarn.

FIG. 4 is a front view showing an example of a conventional false twist device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Undrawn polyester yarn 2 Supply roller 3 Heating roller 4 Holding roller 5 False twisting tool 6 Stretching roller 7 Spindle type winding device 8 Pan a Conventional one-stage heater false twisting yarn b Conventional two-stage heater false twisting yarn c False twisted yarn of the present invention

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-56-148926 (JP, A) JP-A-2-1755941 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D02G 1/00-1/08 D01D 5/084 D02J 1/22

Claims (2)

(57) [Claims] 1. A false twisting process in which an undrawn polyester yarn is heated in a non-twisted state by contacting with a heating body at 70 to 140 ° C., and then simultaneously drawn and twisted with the heating end point as a twisting start point. A yarn, wherein there is variation in crimp between the single fibers constituting the false twisted yarn, and a peak temperature of thermal stress of the false twisted yarn is 170 ° C. or less. False twisted yarn. 2. The heating means is a heating roller.
The false twisted yarn according to the above.