JPS5942089B2 - Manufacturing method of synthetic fiber bulk yarn - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention uses highly oriented undrawn polyester yarn as a starting material,
The present invention relates to a method for producing yarn with excellent bulkiness and loop and slack fixing effects using a drawing and simultaneous temporary twisting method.

[Prior art and its problems]

Synthetic fibers crimped by twisting, pressing, etc. have elasticity and bulk, but have drawbacks such as shedding and snagging when made into knitted fabrics.

In order to improve these defects, attempts have been made to subject the crimped yarn to various treatments and processing, but the cost is high and the quality improvement effect is insufficient.

In addition, in order to improve the texture of textured yarn, methods are known such as cutting the filament to generate fluff, or producing stable bulky textured yarn using fluid jet processing. Processed yarn that has been cut to create fluff has a texture that is inferior to that of spun yarn, and fluid jet processing still has problems in terms of manufacturing cost and stabilization of bulk. There is.

As a publicly known example similar to the present invention, Japanese Patent Publication No. 47-34
254, Japanese Unexamined Patent Publication No. 49-27645, etc.

The former technique is characterized in that the false twisting process is performed under twisted conditions, and then it is relaxed to generate twisted loops intermittently, while the latter technique performs stretching and false twisting in two separate steps. There is that characteristic.

However, these techniques require stretching at a low stretching ratio according to the birefringence Δn of highly oriented undrawn polyester yarn, false twisting at the same time as stretching, relaxation treatment to create uniform loops and slack, and final focusing. Since these techniques do not take into account the fact that the fibers are heated at 200 to 240°C, they do not cause the thick-and-thin effect (the effect of having thicker parts in the longitudinal direction of the fibers), the partial fusion effect, and the generation of loops and sag. , and still have problems in fixing effect, misalignment, and anti-snagging effect, and there has been a demand in the art for improvement of these drawbacks.

[Object of the present invention]

The present invention uses highly oriented undrawn polyester yarn as a starting material,
Provided is a method for producing a synthetic fiber bulk material with uniformity, stable bulk quality, and good appearance characteristics by using a low stretching ratio, temporary twisting at the same time as stretching, followed by relaxation treatment, and then fusion and convergence treatment. The purpose is to

In other words, by causing uneven stretching in the filaments that make up the yarn, making it a thick and thin yarn, by causing fusion in the unstretched portions, generating loops uniformly, and fixing these loops and slack, and by making the yarn bulky. The purpose of this structure is to prevent slippage and snagging.

[Configuration J of the present invention In order to achieve the above object, the present invention consists of the following configuration.

"A polyester synthetic fiber multifilament undrawn yarn having a birefringence of 15 x 10-3 to 60 x 10" is supplied, and the birefringence Δn and the drawing ratio R of the supplied yarn satisfy the following formula 1, and After stretching, temporary twisting is performed at a low magnification so that the fineness D (unit: denier) and number T (number of twists per 1 m) satisfy the formula 1 after stretching, followed by relaxation treatment. After that, each constituent filament is made to develop a loop, and after that, each constituent filament is bundled in the loop-developed state and heat-treated at a temperature of 200 to 240°C to form a partially fused part and to form a loop uniformly on the surface of the yarn. , a method for producing synthetic fiber umbrellas characterized by forming sag.

1.97-0.51 log (Δn×103)〈R〈
3.51-1.20 log (ΔnX103)...
...... I The birefringence of polyester synthetic fibers is a criterion for the stability of the fiber properties, and in particular, mechanical and thermal properties are important.

The present invention determines the range of the draw ratio at the time of temporary twisting based on the relational expression with the birefringence Δn of the supplied yarn, and performs drawing and simultaneous temporary twisting at that draw ratio, thereby producing a thermally sensitive yarn. However, this relational expression was obtained experimentally, and by processing in this way, the processed filament will have random drawing unevenness in the length direction and cross-sectional direction of the yarn after drawing. It gives rise to

Generally, in order to induce drawing unevenness, a method of drawing an undrawn yarn at a low magnification is known, but it is difficult to cause random drawing unevenness as described above just by a simple stretching action.

In the present invention, in particular, since the undrawn yarn is stretched and drawn at the same time, the stretching ratio of the outer layer filament of the stretched yarn is higher than that of the inner layer filament, and the distance between each filament in the cross-sectional direction of the yarn is higher than that of the inner layer filament. A difference in stretching occurs, and since each filament undergoes migration during stretching, a difference in stretching also occurs in the length direction of the same filament.

The irregularity is mostly determined by the microcrash during addition.

Regarding temporary twist numbers, the Koechlin or Heberlein equations are generally known, but the 30
By providing a temporary twist number of ~95%, preferably between 50 and 90, each filament is given strong swirling properties and develops twist loops through the post-process relaxation treatment.

Regarding the heat setting of this temporary twist, it is important to minimize the heat history as much as possible in order to maintain the heat sensitivity of the stretched part due to uneven stretching, but it is necessary to heat set to add swirlability. The heat setting temperature is determined by the birefringence of the supply system and the stretching ratio during stretching.

The relaxation process can be performed, for example, by applying overfeed between two pairs of rollers, and by changing the overfeed rate, it is possible to adjust the number and size of loops.

Furthermore, if the loop is insufficiently expressed, active relaxation treatment such as heating relaxation may be performed.

The final focusing heat treatment fixes the yarn while including the loop shape, and by passing it through a normal heater such as a hot plate, the low-stretched portions of the yarn are fused. , the yarn form is stabilized.

In this case, the heat treatment temperature is set to 200 to 240°C, so that fused areas and non-fused areas coexist, and low-stretched areas and high-stretched areas correspond to the roughness of the yarn as a whole. A yarn is obtained that is not hard and has a welding force sufficient to resist the elongation of the loop.

FIG. 1 is a schematic side view illustrating an embodiment of the invention.

The supply system 1 is a polyester highly oriented undrawn yarn (
The yarn is a multifilament yarn) and is supplied to the temporary weaving zone via a yarn guide 2 and a supply roller 3.

The supplied yarn 1 is heated and fixed by the first heat treatment device 4 while being stretched and simultaneously stretched by the first temporary twisting device 5, passed through the first temporary twisting device 5, unraveled, and then unraveled by the first temporary twisting device 5. After passing through the delivery device 6, each filament is relaxed between the delivery device 6 and the second delivery device 7, and each filament randomly develops a loop.

Next, the yarn fed out from the second feeding device 7 is bundled in a loop-forming state by a second temporary twisting device 9 or a fluid entangling treatment means commonly used in the art, while being subjected to a second heat treatment device 8. The low-stretched portion of the yarn is melted, a partial bonding process is performed between the filaments, and the yarn is passed through the third delivery device 10.
It is wound up by the winding device 11.

The stretching ratio in this case can be given by the speed ratio of the supply roller 3 and the first delivery device 6,
The value can be determined experimentally while taking into account the proportion and extent of the low stretch portion.

Further, the temperature of the second heat treatment device 8 also needs to be selected depending on the state of this low stretching portion.

FIG. 2 is a graph showing the relationship between the birefringence Δn of the supply system and the stretching ratio R. From this graph, it is possible to determine the range of the stretching ratio to obtain the appropriate ratio of the low-stretched part and the high-stretched part. can.

The hatched area in Figure 2 indicates the appropriate range; in area A, there are too many high-stretched parts and the fusion in the post-process is insufficient, and in area C, low-stretched parts are the main part. As a result, the fused yarn becomes coarse and hard, causing uneven dyeing, or impairing the quality of the bulky processed yarn, such as stiffness and texture.

Figure 3 shows the relationship between the number of temporary twists and the occurrence of loops in the first temporary twisting process, and when viewed as a reduction rate with respect to Koechlin's general formula regarding fineness and number of temporary twists, the number of loops decreases between 40 and 60. This is the maximum, but considering the stability and randomness of the loop in combination with the degree of relaxation, 3
It may be freely selected within the range of 0 to 95.

[Effects of the present invention]

In the method of the present invention, a simultaneous stretching step at a low magnification, a relaxing step, and a partial fusion treatment step can be carried out continuously in a series of steps, so that efficiency and productivity are excellent.

In particular, it actively causes stretching unevenness, causes fine thick and thin sheets, and fusions in unstretched areas, and fixes loops and slack, thereby preventing slippage and sticking (
It has the unique effect of improving defects such as the phenomenon in which single fibers easily protrude from the tissue due to snagging.

Furthermore, the obtained yarn can have uniform and stable bulk properties and excellent appearance characteristics.

This will be explained in detail below using examples.

Example 1 Processing was carried out according to the embodiment illustrated in FIG. 1 under the following conditions.

Feeding system: Polyester synthetic fiber 190D-48f Birefringence Δn=35X10 a (The stretching ratio for normal temporary warping is 1.8 times) Feeding speed: 170 m/min First delivery speed: 238 m/min ( Stretching ratio 1
．． 4 times) Number of first temporary strands: 1500 T/M First heat treatment temperature: 140°C Second delivery speed: 173 m/min Third delivery speed: 185 m/min Number of second temporary strands: 830 T/M Second heat treatment Temperature: 220°C The obtained processed yarn has loops inside and on the outer periphery of the yarn.
It had a mixture of sagging and roughness, good surface properties, and stable convergence.

When this processed yarn was used for weaving, a fabric was obtained that had significantly improved sticking and air permeability, which are disadvantages of ordinary synthetic fiber processed yarn fabrics.

As described above, the present invention can be carried out using a normal temporary twisting device, and the obtained textured yarn can be looped inside and on the outer periphery of the yarn.

It has a mixture of slack and the entire yarn is focused and fixed by partial fusion parts, and it has excellent bulk quality and excellent surface effect of the yarn, and is suitable for tension in fabric fabric manufacturing processes, etc. It has sufficient stability against.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view illustrating an embodiment of the present invention, FIG. 2 is a graph showing the relationship between the birefringence Δn of the supply system and the stretching ratio, and FIG. 3 is a graph showing the relationship between the temporary refraction number and the loop formation. This is a graph showing the relationship with gender. 1: Supply system, 2: Yarn guide, 3: Supply roller, 4
: first heat treatment device, 5: first temporary twisting device, 6: first delivery device, 7: second delivery device, 8: second heat treatment device, 9
: 2nd tentative device, 10: 3rd feeding device, 11: winding device.

Claims (1)

[Claims] 1. A polyester synthetic fiber multifilament undrawn yarn having a birefringence of 15X10' to 60X10' is supplied, and the birefringence Δn and the drawing ratio B of the supplied yarn satisfy the following formula: In addition, temporary twisting was performed at the same time as the stretching at a low magnification and twist so that the fineness D (unit: denier) and the number T (number of square feet per 1 m) after stretching satisfied the formula ■. After that, each constituent filament is subjected to a relaxation treatment to develop a loop, and then each constituent filament is bundled in the loop-developed state and heat-treated at a temperature of 200 to 240°C to form a partially fused portion and to improve the surface of the yarn. A method for producing bulky synthetic fiber yarn, which is characterized by uniformly forming loops and slack. 1.97-0.51 log (Δn x 103)
(R(3,51-1,20log (ΔnX103)・
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