JP2698625B2 - Method for producing multilayer crimped yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a crimped yarn having a multilayer structure having a wool spun yarn-like appearance and feeling and not causing fluff or single yarn breakage during weaving and knitting. And a method for producing the same.

(Prior art) Conventionally, a false twisted crimped yarn obtained by false twisting a thermoplastic synthetic fiber filament yarn is extremely bulky in the state of the textured yarn itself, that is, under micro tension close to no tension. However, when this is made into a woven or knitted fabric, there is a disadvantage that most of its sublimeness is lost.

In addition, two multifilament yarns with different elongations were used as supply yarns, and they were aligned and false twisted, and the high elongation multifilament yarn was positioned on the outer layer and the low elongation multifilament yarn was positioned on the inner layer. A crimped yarn having a two-layer structure is also known. Even if the crimped yarn is subjected to tension during weaving and knitting, most of the tension is applied to the core yarn and almost no tension is applied to the sheath yarn, so that the fabric is formed while maintaining the bulkiness and gives a sense of volume. On the other hand, since there is no entanglement between the core yarn and the sheath yarn, the core yarn and the sheath yarn are easily displaced by a slight wrinkle during weaving and knitting. Since the fabric is knitted, the resulting fabric is a disadvantage, and may not be practically used.

Japanese Patent Application Laid-Open No. Sho 61-194230 discloses a method for producing a crimped yarn having a multi-layer structure, which provides a feeling effect due to bulkiness and does not shift against ironing during weaving and knitting.
No. pp. 139 to 163. However, the above method uses a pin-type false twisting machine with a large twisting power.
The degree of crimp is significantly different between the relaxed heat-treated yarn and the untreated yarn, which causes a large difference in yarn length between the two yarns, causing loop fluffing and easy breakage during false twisting. It was difficult to process at a high speed of more than a minute. In addition, if the difference in physical properties of the two yarns supplied to the false twisting process is reduced to reduce the difference in yarn length and prevent yarn breakage, the bulkiness of wool spun yarn cannot be imparted. There is.

(Problems to be Solved by the Invention) The present invention solves the above-mentioned drawbacks of the conventional crimped yarn, has the appearance and feeling of a wool spun yarn, and has a fluff ball or a single yarn during weaving and knitting. An object of the present invention is to provide a method for producing a multilayer-structured crimped yarn capable of producing a crimped yarn without breaking at a high speed.

(Means for Solving the Problems) That is, according to the present invention, a polyester multifilament yarn having a cutting elongation of 80 to 150% is relaxed at a heater temperature of 250 ° C. or more, a treatment time of 0.2 seconds or less, and a relaxation rate of 5 to 30%. Heat-treated, then relaxed heat-treated yarn and elongation at break of 80 ~
Abstract: A method for producing a multilayer-structured crimped yarn, characterized in that a 150% polyester multifilament yarn is aligned and subjected to draw friction false twisting at a yarn speed of 200 m / min or more, followed by fluid entanglement treatment. It is assumed that.

In the present invention, the fluid treatment may be performed before the stretch friction false twisting, instead of after the stretch friction false twisting.

 Hereinafter, the present invention will be described in detail.

First, the yarn supplied to the relaxation heat treatment in the present invention is:
It is a polyester multifilament yarn having a breaking elongation of 80 to 150%, preferably 100 to 130%, and a boiling water shrinkage of 10% or more, particularly preferably 10 to 80%. Cutting elongation is 150
%, It becomes brittle at the time of relaxation heat treatment or friction false twisting, causing thread breakage, which makes it unusable for use.

Similarly, for the yarn not subjected to the relaxation heat treatment, it is necessary to use a polyester multifilament yarn having a cutting elongation of 80 to 150%, preferably 100 to 130%. If the elongation at break exceeds 150%, it will easily change over time, and if it is subjected to friction false twisting, thread breakage and fluff will easily occur, causing problems in operability. On the other hand, if the elongation at break is less than 80%, the elongation is too low, and fluff is likely to be formed by the stretch friction false twisting, which is not preferable.

In the present invention, the polyester multifilament yarn having a breaking elongation of 80 to 150% is first subjected to relaxation heat treatment. The relaxation heat treatment conditions are a heater temperature of 250 ° C or more, a treatment time of 0.2 seconds or less, and a relaxation rate of 5 to 30%. There is a need.

That is, in the relaxation heat treatment of the present invention, by setting the relaxation rate to 5 to 30%, a difference in crimp can be provided between and within the filaments constituting the yarn by the subsequent friction drawing false twisting, Irregularities in the heat treatment that can give a yarn length difference that does not cause fluff due to ironing during weaving and knitting with other yarns to be aligned can be generated.

On the other hand, if the relaxation rate is less than 5%, the difference in crimp and the difference in yarn length cannot be imparted by the subsequent stretch friction false twisting.
On the other hand, if it exceeds 30%, the yarn length difference is too large, and even if a fluid entanglement treatment is performed, fluffing is generated by ironing during weaving and knitting, which is not preferable.

In addition, the heater temperature during the relaxation heat treatment is set at 250 ° C or higher, and the upper limit is about 600 ° C, and the heat treatment is performed for a short time of 0.2 seconds or less to give a crimp difference between and within the filaments constituting the yarn. Heat treatment spots can be generated to the extent possible, and if the heater temperature is lower than 250 ° C., heat spots cannot be generated so that a crimp difference can be imparted by short-time heat treatment of 0.2 seconds or less.

The reason why the treatment time during the relaxation heat treatment is set to 0.2 seconds or less is as follows. That is, as the relaxation rate during the relaxation heat treatment increases, the amount of shrinkage of the yarn increases, and the occurrence of loops and slacks in the single filament increases. For this reason, if the heater during the relaxation heat treatment is long, the yarn runout increases, and the heater contacts the surface of the heater to cause fusion or breakage of single yarn, resulting in poor operability. Therefore, in order to cause heat treatment spots between and within the filaments constituting the yarn with good operability, it is necessary to use a heater as short as possible and at a high temperature. In the present invention, in order to perform stretch friction false twisting at a high speed of 200 m / min or more following the relaxation heat treatment, the above problem cannot be solved unless the heater length is 1 m or less. , A relaxation heat treatment for a short time of 0.2 seconds or less is required, and preferably in the range of 0.1 to 0.2 seconds.

On the other hand, if the heat treatment time exceeds 0.2 seconds, the filament comes into contact with the surface of the heater, causing fusion or breakage of single yarn,
It is not preferable because the filament is heated uniformly and no heat treatment spots are generated.

In the present invention, the yarn subjected to the relaxation heat treatment and the yarn not subjected to the relaxation heat treatment are aligned and subjected to stretch friction false twisting at a high speed of 200 m / min or more. By stretch friction false twist processing,
In the heat-treated yarn, crimp spots and fine spots occur differently among the constituent filaments, and the crimping and fine spot differences of each filament also occur in the length direction. A composite false twisted yarn having a more remarkably crimped form and fineness difference with the filament.

The draw false twisting process is performed using the friction false twisting method when the difference in yarn length between the relaxed heat-treated yarn and the non-relaxed heat-treated yarn is caused by a pin-type false twisting method with a large twisting force. This is to prevent the size from becoming too large and to facilitate high-speed machining.

As described above, in the present invention, the drawing friction false twisting is performed at a yarn speed of 200 m / min or more. However, the yarn speed referred to in the present invention refers to a take-off roller from the drawing friction false twisting region [ A first delivery roller (9) described later].

In the present invention, the false twisted yarn obtained above is subjected to a fluid entanglement treatment to mix and entangle the respective filaments, so that the two kinds of yarn are well entangled and the loop fluff is finely formed. Is obtained.

Conventional multi-layer crimped yarn has a large difference in yarn length after false twisting, and is wound by alternate twisting of S and Z, or fused and bundled, but can be obtained by the present invention. In the multilayer crimped yarn, crimp unevenness and fineness unevenness occur randomly at short intervals between filaments and in the length direction of the filament, and there is almost no difference in yarn length between the two yarns. Since they are entangled by mixing and entanglement, there is swelling. If weaving and knitting, it is possible to obtain a woven and knitted fabric that is soft and taut, has a waist, and has the appearance and feel of a wool spun yarn. In addition, since the yarns between the two yarns having almost no difference in yarn length are mixed and entangled, fluffing or single yarn breakage does not occur even when ironing occurs during weaving and knitting.

If the single yarn fineness of the polyester multifilament yarn subjected to the relaxation heat treatment is made smaller than the single yarn fineness of the polyester multifilament yarn not subjected to the relaxation heat treatment,
On the surface of the yarn after drawing friction false twisting, the finer single yarn fineness appears on the surface, and the woven or knitted fabric obtained by weaving and knitting this crimped yarn has a softer surface, tightness, and tightness. It becomes something with.

In the above embodiment, the fluid entanglement treatment is performed after the stretch friction false twisting. However, the fluid entanglement treatment may be performed before the stretch friction false twisting. What is necessary is just to select according to the combination of yarn and operability.

Further, the relaxation heat treatment and the stretch friction false twisting may be performed in separate steps, but are preferably performed continuously.

As the polyester in the present invention, polyethylene terephthalate and a copolyester mainly composed of polyethylene terephthalate are preferably used.

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

FIG. 1 is a schematic process diagram showing one embodiment of the present invention. In FIG. 1, a polyester multifilament yarn (1) is subjected to relaxation heat treatment by a heater (4) between a first feed roller (3) and a second feed roller (5) via a first feed roller (3). Next, the second feed roller (5) aligns with the polyester multifilament (2), and the second feed roller (5).
And at the same time, while being stretched between the second feed roller (5) and the first delivery roller (9), while being twisted by the friction false twist device (8), the heat is fixed by the heater (6), and the cooling plate ( Through 7), it is supplied to the first delivery roller (9). Subsequently, after being mixed and entangled by the fluid entanglement device (10) provided between the first delivery roller (9) and the second delivery roller (12), the second
It is wound up as a package (13) via a delivery roller (12).

The fluid entanglement device (10) is provided between the first feed roller (3) and the second feed roller (5) instead of between the first delivery roller (9) and the second delivery roller (12) and stretched. Before the friction false twisting, a fluid entanglement treatment may be performed. Also, the first delivery roller (9) and the second delivery roller (9)
A heater (11) may be provided between the delivery roller (12) and reheat treatment to reduce the torque of the false twisted yarn and improve the crimped form.

FIG. 2 is a schematic side view showing one embodiment of a multilayer crimped yarn obtained by the present invention. In the multilayer crimped yarn obtained by the present invention, the yarn that has been subjected to the relaxation heat treatment is a low crimped yarn having a mixture of crimp unevenness and fineness unevenness, and forms a sheath portion having a loop. The non-yarns become high crimped yarns and are bundled in the core, and the core yarns and the sheath yarns are mixed and entangled with each other to form yarns. It is a multilayer crimped yarn having a mixture of strips.

(Examples) Hereinafter, the present invention will be specifically described based on examples.

Examples 1 to 3, Comparative Examples 1 to 5 According to the steps shown in FIG. 1, 220d having various cutting elongations obtained by spinning polyethylene terephthalate at a high speed.
/ 72f polyester multifilament yarn is subjected to a relaxation heat treatment, and then aligned with a 230d / 30f unheated polyether multifilament yarn in a twist false-twisting machine with a twist configuration of 1-10-1. After stretch friction false twisting, followed by fluid entanglement treatment, it was wound into a package.

In Example 3, a multilayer crimped yarn was manufactured in the same manner as in Example 1 except that the fluid treatment was performed before the drawing friction false twisting, instead of after the drawing friction false twisting. Processing was performed using a pin-type false twisting machine.

Tables 1 and 2 show the cutting elongation of the supplied yarn and the processing conditions.

In the processed yarn obtained in Examples 1 and 2, the 150d / 72f yarn forms a sheath while exhibiting a loop shape and forms a core.
It was a multi-layer crimped yarn with a core-sheath structure entangled in a 150d / 30f yarn shape.

This multi-layer crimped yarn has a density of 66 threads / 2.54 cm and a weft density of 57
This fabric was woven in a 2/2 twill structure of 2.54 cm / 2.54 cm, and the obtained woven fabric was dyed and finished in the same manner as a normal polyester yarn.

As is clear from Table 1, the evaluation results of the finished woven fabric by the feel of the hands were similar to those of the woven fabric made of wool spun yarn in terms of feeling, tension, waist, and volume.

The third embodiment differs from the first and second embodiments in the position where the fluid entanglement process is performed. However, the air pressure at the time of the fluid entanglement is slightly higher than that of the first embodiment, and the D / Y during the stretch friction false twisting is adjusted. As a result, the same multilayer crimped yarns as in Examples 1 and 2 were obtained.

On the other hand, in Comparative Example 1 using a yarn having a cutting elongation of 60% as the yarn subjected to the relaxation heat treatment, and in Comparative Example 2 using a yarn having a cutting elongation of 210% as the yarn not subjected to the relaxation heat treatment. None of the crimped yarns had a multilayer structure, and the woven fabric from the crimped yarn was rough and had the texture of a normal processed yarn woven fabric.

Further, in Comparative Example 3 in which the heater temperature during the relaxation heat treatment was 200 ° C., the effect of the relaxation heat treatment was poor, and the processed yarn was aligned, and a crimped yarn having a core-sheath structure was not obtained. In Comparative Example 4 in which the relaxation rate during the relaxation heat treatment was set to 40%, a multilayer crimped yarn was obtained. However, since the loop of the relaxed heat-treated yarn was too large, flaking was caused by ironing during weaving. The woven fabric from the crimp was of poor quality.

Further, in Comparative Example 5 in which a pin type false twisting machine was used in place of the friction false twisting machine, the sheath of the crimped yarn obtained in the same manner as in Comparative Example 4 was loosened, and fluff balls were used during weaving. However, even when weaving, a woven fabric having a wool-like texture was not obtained.

(Effect of the Invention) As described above, the method for producing a multilayer crimped yarn according to the present invention is a method in which a polyester multifilament yarn is subjected to heat treatment at a high temperature for a short time at a low relaxation rate, and is not subjected to a relaxation heat treatment. Since the stretch friction false twisting is performed in line with the above, the yarn becomes almost false with a little difference in yarn length and a large difference in crimp between and within the filaments, and then fluid entangled before or after the stretch friction false twisting By performing the treatment, a core-sheath multilayered crimped yarn can be obtained.

As described above, the obtained multilayer crimped yarn has almost no difference in yarn length, and has a core-sheath structure in which two yarns are mixed and entangled. Even if it is received, fluff balls and single yarn breaks do not occur, and a woven / knitted fabric similar in volume and softness to a woven / knitted fabric using wool spun yarn can be obtained.

In addition, since processing is performed at a high speed of 200 m / min or more, a crimped yarn having a multilayer structure like a wool spun yarn having the above advantages can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic process diagram showing one embodiment of the present invention, and FIG.
The figure is a schematic side view showing one embodiment of a multilayer crimped yarn obtained by the present invention. (1) (2) Polyester multifilament yarn (4) (6) Heater (7) Cooling plate (8) Friction false twist device (10) Fluid entanglement device

Claims (2)

(57) [Claims] 1. A polyester multifilament yarn having a cutting elongation of 80 to 150% is heated at a heater temperature of 250 ° C. or more for a processing time of
Heat-relaxed at a relaxation rate of 5 to 30% for 0.2 seconds or less, then align the relaxed heat-treated yarn with a polyester multifilament yarn with a cutting elongation of 80 to 150% at a yarn speed of 200 m / min or more. A method for producing a crimped yarn having a multilayer structure, comprising performing a fluid entanglement treatment after performing a drawing friction false twisting process. 2. The method for producing a multilayer crimped yarn according to claim 1, wherein said fluid treatment is performed before drawing friction false twisting instead of after drawing friction false twisting.