JPH05287633A - Production of crimped yarn - Google Patents

Abstract

PURPOSE:To provide crimped yarn excellent in shape of crimps and randomness of phase by drawing highly oriented and undrawn polyester yarn under specific conditions and then crimping the resultant yarn. CONSTITUTION:Highly oriented and undrawn polyester yarn 1 is drawn for 0.01-0.15 sec passage time while being heated at 300-700 deg.C between a feed roller 2 and a delivery roller 4 with a noncontact type heating heater 3. Crimps are subsequently applied to the resultant drawn yarn with a heating fluid pushing nozzle 5 and the crimped yarn is passed through a cooling part 6 and take-off rollers 7 and wound into a package 9 with a winder 8.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a highly crimped polyester highly oriented unstretched yarn which is excellent in crimp morphology and phase randomness by using a heating fluid pushing nozzle (hereinafter simply referred to as a nozzle). It relates to a method for producing a yarn.

[0002]

2. Description of the Related Art As one of the methods for applying crimps to polyester multifilament yarns for clothing, there is a heating fluid indentation method, which is used as a method for imparting actual and latent crimps to yarns.

In this heating fluid pushing method, generally, a drawn yarn is used as a supply yarn, and the yarn is heated by a heating body such as a contact heater or a heating roller to a temperature (about 150 to 230) at which fusion does not occur.
After preheating at (° C.), it is immediately supplied to the nozzle to open the yarn, impart latent and actual crimps, and then cool and wind.

[0004] In this method, since the yarn is crimped in the opened state, the obtained crimped yarn is random (random crimpability) because the crimp phase is not uniform in each filament. .. This random crimping property can be said to be similar to natural fiber in a sense, and it is a feature that is significantly different from the processed yarn obtained by false twisting, which is the mainstream of crimping, and depending on the application. It is a characteristic suitable for imparting an excellent texture to a woven or knitted fabric.

However, in the conventional heating fluid indentation processing,
Improving the crimpability is more important than improving the random crimpability. Therefore, the crimpability is improved by directly contacting the yarn with the heating body in advance and usually preheating for longer than 0.15 seconds. I was trying. In fact, the present inventors have confirmed that unless such preheating is performed, the crimpability of the obtained textured yarn is lowered.

However, the preheating by contact with the heating body heats each filament constituting the yarn evenly, so that there is almost no difference in the thermal characteristics between the filaments. In the yarn treated in this way, since the crimps are imparted to each filament independently by opening in the nozzle, random crimpability is imparted to the filaments. Since the characteristics are at the same level, the processed yarn has a relatively uniform crimp size and less unevenness. Therefore, the textured yarn obtained by the conventional heating fluid indentation has insufficient random crimpability, and has a crimp structure of a relatively uniform size. It was not possible to make full use of the characteristics of the above in the texture of the woven or knitted fabric, and it was not possible to obtain a material that greatly deviated from the texture of the woven or knitted fabric by using the false twist textured yarn.

[0007]

As described above, in the conventional heating fluid indentation method, a textured yarn having both crimp morphology and phase randomness cannot be obtained. The present invention has been made in view of the above circumstances, and provides a method for producing a crimped yarn which is excellent in the form and phase randomness of crimps and can fully utilize its properties when formed into a woven or knitted fabric. This is a technical issue.

[0008]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, polyester highly oriented undrawn yarn was used at high temperature using a non-contact type heater, and The present invention has been achieved by finding that the purpose can be achieved by drawing the material in a crimping step after stretching in a short time.

That is, according to the present invention, a highly oriented polyester undrawn yarn is drawn by using a non-contact type heater and then crimped with a nozzle at a temperature of 300 to 700 ° C. The gist of the present invention is a method for producing a crimped yarn, which comprises drawing under the condition that the passing time of the heater is 0.01 to 0.15 seconds and then crimping.

The present invention will be described in detail below.

In the present invention, a polyester highly oriented undrawn yarn (hereinafter abbreviated as POY) is used as a supply yarn, and the polyester in the present invention means polyethylene terephthalate (hereinafter abbreviated as PET) or. It means polyalkylene terephthalates such as polybutylene terephthalate and polyesters containing them as a main component, and PET is particularly preferable from the viewpoint of mechanical properties and thermal properties.

POY is a multifilament produced by a conventional high-speed spinning process. For example, a PET yarn having a birefringence of about 20 × 10 ⁻³ to 80 × 10 ⁻³ is preferably used. A low orientation undrawn yarn obtained by conventional low speed spinning is not preferable because it tends to cause fusion between filaments when drawn at a high temperature of 300 ° C. or higher.

In the present invention, first, POY is heated to 300 to 700 ° C. by using a non-contact type heater and is stretched under the condition that the yarn passing time of the heater is 0.01 to 0.15 seconds. is necessary.

The purpose of the above treatment is, firstly, to heat the yarn uniformly macroscopically and nonuniformly microscopically by using a non-contact type heater. That is, the yarn as a whole receives heat uniformly from the surroundings,
While maintaining various properties such as strength and elongation in the longitudinal direction of the yarn, the filaments located in the surface layer and the inner layer of the multifilament yarn, and in the case of the monofilament, the heat receiving effect on the surface and inside It is one of the important points to make different. By treating the filaments so that the heat-receiving effect is different between and within the filaments, the randomness and phase randomness of the crimp size and direction are emphasized when crimping is applied in the subsequent nozzle. It becomes possible to do.

Second, the temperature of the non-contact type heater is set to 300
By setting the temperature to ˜700 ° C. and the passing time of the yarn through the heating heater within the range of 0.01 to 0.15 seconds, the difference in the heat receiving effect between the filaments and between the filaments is significantly given. If the heater temperature is lower than 300 ° C or the passage time is shorter than 0.01 seconds, the heat treatment effect will be insufficient. Also, the heater temperature exceeds 700 ° C or the passage time is 0.
If it is longer than 15 seconds, the entire filament gets enough heat,
There is no difference in the heat-receiving effect between the filaments and in the filaments, and as a result, the crimp morphology and phase randomness are reduced. A preferable heat treatment condition is a heater temperature of 350 to
The temperature is 600 ° C and the transit time is 0.03 to 0.12 seconds. Another important point is that the process is performed at such a high temperature in a short time.

Third, the temperature of the non-contact type heater is set to 300
By setting a high temperature of up to 700 ° C., the oil agent or the like applied to improve the focusing property of POY in the spinning process is sublimated and removed. When the oil agent applied to POY is removed, the fiber opening property in the nozzle is improved, and the crimping processability itself can be significantly improved. Moreover, since the non-contact type heater is used, there is no problem of heater contamination due to adhesion of oil agent or the like, which is advantageous in terms of operability and maintenance.

Fourthly, the POY is stretched under the above-mentioned conditions while giving a difference in heat receiving effect between the filaments and in the filaments, thereby microscopically producing stretching unevenness,
This is to promote the randomness of the crimp morphology and phase. The draw ratio of POY at this time is preferably about 1.2 to 2.0, although it depends on the birefringence and the elongation.

In the present invention, after the POY has been subjected to the above-mentioned stretching treatment, it is crimped by a nozzle, and then the yarn is cooled in a cooling section to obtain a processed yarn excellent in crimp form and phase randomness. To get

The reason why the processed yarn excellent in the crimp morphology and phase randomness is obtained in the present invention is considered to be as follows. That is, in the present invention, unevenness due to the heat-receiving effect between the filaments and inside the filaments during the stretching of POY,
In connection with this, various microscopic irregularities such as irregularities due to stretching occur, so when crimping with a nozzle, even if the same nozzles and processing conditions as before are adopted, the conventional crimped form It is considered that crimps, which are greatly different and have different sizes between filaments and within filaments, and random orientations, are caused by the microscopic unevenness.

Further, in the present invention, since the yarn opening property is improved by subjecting the POY to the above-mentioned stretching treatment, the crimping workability by the nozzle can also be improved.

The non-contact type heater used in the present invention is
The structure is not particularly limited as long as the yarn does not directly contact the surface of the heating body, and macroscopically can uniformly heat the yarn. Further, for example, a guide or the like may be provided in the yarn running portion of the non-contact type heater so that the running state of the yarn is not significantly disturbed. The guide and the like are indirectly heated by the heat of the heater, and the yarn directly contacts the indirectly heated guide and the like, but the contact time is substantially point contact and the contact time is extremely short. It can be used as a non-contact type heater.

The yarn supply rate during crimping is POY
The overfeed rate is usually about 10 to 70%, although it varies depending on the type and fineness, the type of heating fluid, the temperature of the nozzle, and the like. The nozzle and cooling unit used for crimping do not require any special device or modification, and conventional nozzles and cooling units such as the nozzle described in JP-A-46-972 can be used as they are. Further, as the heating fluid supplied to the nozzle, air, air containing steam, nitrogen, argon or the like can be used, but air is preferable from the viewpoint of cost.

Next, the present invention will be described with reference to the drawings.

In order to carry out the present invention, for example, as shown in FIG. 1, a feed roller 2, a non-contact type heater (non-contact type super high temperature heater) 3, a delivery roller 4, a nozzle 5 and a cooling section are arranged in this order. 6, take-up roller 7 and winding device 8
It suffices to use a processing machine equipped with a non-contact type ultra-high temperature heater 3 in addition to the conventional processing machine.

Next, one embodiment of the present invention will be described with reference to FIG. First, the supply yarn POY1 is sent out by the feed roller 2 and guided to the delivery roller 4 via the non-contact type super high temperature heater 3. At this time, POY1
It is stretched between both rollers 2 and 4 under the condition that the heater temperature is 300 to 700 ° C. and the POY transit time in the heater part is 0.01 to 0.15 seconds. The stretched yarn is supplied from the delivery roller 4 to the nozzle 5 together with the heated air in the overfeed state, is crimped, is cooled in the cooling unit 6, is passed through the take-up roller 7, and is wound in the package 9 by the winding device 8. It is rolled up by.

[0026]

EXAMPLES Next, the present invention will be specifically described by way of examples.

Examples 1 to 3 and Comparative Examples 1 to 2 POY150d / 72f of PET having a birefringence of 54 × 10 ^-3 was used as the feed yarn, and the drawing heat treatment conditions are shown in Table 1 according to the processing steps shown in FIG. As shown, various modifications were performed for stretching and fluid heat indentation.

As the nozzle, the same nozzle as that described in JP-A-46-972 is used, the temperature of the nozzle is 200 ° C. by using air as the heating fluid, and the overfeed rate between the delivery roller and the take-up roller is It was set to be 30%. In Comparative Example 2, a non-contact type heater was not used,
The delivery roller was heated and processed.

The obtained processed yarn is woven and then dyed according to a conventional method to obtain a warp density of 140 threads / 2.54 cm, a weft density of 1
05 pieces / 2.54 cm woven fabric was obtained. Table 1 also shows the evaluation results of the obtained textured yarn and woven fabric.

[0030]

[Table 1]

As is clear from Table 1, the processed yarns obtained in Examples 1 to 3 have random crimps, and the woven fabrics obtained from these processed yarns are excellent in swelling feeling and warmth. It was a thing.

On the other hand, the textured yarns obtained in Comparative Examples 1 and 2 are
The random crimpability was inferior, and the woven fabrics obtained from this processed yarn were inferior in the swelling feeling and warmth to those of Examples 1 to 3.

[0033]

According to the present invention, it is possible to easily and stably produce a crimped yarn which is bulky and has a crimped form and a random phase. For this reason, when the crimped yarn obtained in the present invention is knitted or woven, it is possible to obtain a cloth which has a texture that is not available in the past and has an excellent bulge and warmth due to the crimped structure.

[Brief description of drawings]

FIG. 1 is a schematic process drawing showing an embodiment of the present invention.

[Explanation of symbols]

 1 Polyester Highly oriented undrawn yarn (POY) 2 Feed roller 3 Non-contact type heater 4 Delivery roller 5 Heated fluid pushing nozzle 6 Cooling section 7 Take-up roller 8 Winding device 9 Package

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuhiro Umino 23 Uji Kozakura, Uji City, Kyoto Prefecture Unitika Ltd. Central Research Laboratory

Claims (1)

[Claims] 1. A polyester highly oriented undrawn yarn is drawn by using a non-contact type heater and then crimped by a heating fluid pushing nozzle at a temperature of 300 to 700 ° C., and
A method for producing a crimped yarn, which comprises drawing a yarn under the condition that the heating heater passes through the heater for 0.01 to 0.15 seconds, and then crimping the yarn.