JPS6231094B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing spun yarn-like yarn, and more specifically, the present invention relates to a method for producing spun yarn-like yarn, and more specifically, by drawing undrawn yarn made of mixed polyester filaments of different fineness under specific conditions, filaments of large fineness can be made non-uniformly in the length direction. The present invention relates to a method for producing a yarn having natural dyeing irregularities similar to a spun yarn by stretching and forming a portion with non-uniform dyeing characteristics. Conventionally, it has been common for filament yarns to be drawn uniformly and to be uniform even when bulked. However, in recent years, people have grown tired of the monotonous appearance and texture of uniform filament yarns, and have begun to prefer the appearance and texture of spun yarns with natural irregularities. Various attempts have been made to do so. Among these, creating dyed spots that look smooth and natural can be said to be a major factor in making the fabric look like spun yarn. As a method of imparting uneven dyeing to the filament yarn, the surface speed of the supply roller or drawing roller may be changed periodically, or a notch may be provided in the nip roller on the supply side and the feeding speed of the drawing roller may be periodically changed by traverse motion. A method is known in which stretching irregularities are caused mechanically during stretching, such as by changing the stretch ratio, or methods are known in which stretching irregularities are left by drastically changing the stretching conditions and, for example, suppressing the stretching ratio to about the natural stretching ratio. However, with the method of mechanically creating stretching irregularities during stretching, when the fabric is made, the entire yarn has locally dark colored areas, resulting in an excessive foreign dyeing effect and a pattern with strong fancy properties. It is not possible to impart a natural color tone similar to that of spun yarn. In addition, if the stretching ratio is extremely reduced to about the natural stretching ratio to leave stretching irregularities, the unstretched residue will concentrate in a certain part of the filament, resulting in the formation of thermally and mechanically weak parts, and the post-processing For example, it has drawbacks such as yarn breakage due to thermal deterioration during false twisting, reduced operability due to troubles during the weaving and weaving process, and hardening of the texture during the dyeing process. For this reason, measures such as aligning with other normal yarns and twisting are essential, making the process complicated. As a result of intensive research to solve the above-mentioned drawbacks of the prior art, the inventor of the present invention has discovered that by drawing an undrawn yarn made of mixed filaments of different fineness under specific conditions, the entire yarn is not dyed deeply. The present invention was achieved by discovering that it is possible to obtain a yarn having natural-looking dyed spots like a spun yarn, in which darkly dyed areas are interspersed with normal dyed areas. That is, in the present invention, the maximum fineness and the minimum fineness after drawing differ by at least 1.4 deniers, and the ratio of filaments with the maximum fineness is at most 3/5.
(weight ratio), and an undrawn yarn made of two or more types of polyester filaments whose birefringence increases as the fineness decreases, at a stretching ratio of 0.65 to 0.78 times the highest stretching ratio of the undrawn yarn, and , hot pin temperature Tp (℃) and hot plate temperature
This is a method for producing a spun yarn-like yarn, which is characterized by drawing so that TpL (°C) satisfies the following conditions. However, Tg−30≦Tp≦Tg＋20, TpL＜Tg
+45, Tg is the glass transition temperature of the polyester filament (°C). The present invention will be explained below with reference to the drawings. 1st
The figure is a schematic side view of an apparatus for implementing the invention. In the same figure, in 2, the maximum fineness and minimum fineness after drawing differ by at least 1.4 deniers, and the ratio of the filament with the maximum fineness is at most 3/5.
(weight ratio) and is an undrawn yarn made of two or more types of polyester filaments whose birefringence increases as the fineness decreases. The polyester referred to in the present invention mainly refers to polyethylene terephthalate, but it may also be a copolymerized polyester containing ethylene terephthalate as a main component and ethylene isophthalate, ethylene oxybenzoate, or ethylene sebacate as a copolymer component. A small amount of additives such as a matting agent and an antistatic agent may be added to the polyester.
In addition, undrawn yarn refers to yarn that has not been substantially drawn after melt spinning, and includes not only undrawn yarn with a birefringence of 0.005 to 0.025 obtained at normal spinning speeds, but also high-speed spinning yarns. Birefringence obtained from 0.025 to
Partially oriented undrawn yarn (POY) of 0.060 may also be used. The cross-sectional shape of the filament constituting the undrawn yarn may be not only a circular cross-section but also a non-circular cross-section such as a triangular cross-section and a multilobal cross-section. Further, filaments having these cross sections may be appropriately combined. In the present invention, the maximum fineness and minimum fineness after stretching are made to differ by at least 1.4 denier in order to provide a natural color tone similar to that of spun yarn. That is, the filament with the minimum fineness is made substantially uniform in the length direction, and the filament with the maximum fineness leaves dark dyed thick portions randomly in the length direction. In this case, as a method for mixing filaments of different fineness, it is rational to simultaneously spin them from a spinning nozzle in which spinning holes of different sizes are arranged, and also in the sense of giving different physical properties to the mixed filaments of different dyeing degrees. preferable. In other words, this difference in physical properties is due to the fact that during spinning, filaments with smaller fineness tend to have a faster cooling rate, a higher birefringence (orientation degree), and a lower draw ratio until breakage. It is thought that then. Such a difference in physical properties increases as the difference in fineness increases. Of course, filaments of different finenesses may be separately spun and then combined or mixed later, but in this case it is necessary to provide the above-mentioned physical property differences to the mixed filaments of different finenesses. The reason why the composition ratio of the filament with the maximum fineness is set to at most 3/5 (weight ratio) is that if the composition ratio exceeds this, the portion with deep dyeing properties will increase and the fancy property will become stronger, resulting in a natural color. This is to prevent the yarn from not only not having the same color tone but also having weak points both thermally and mechanically, which can easily cause problems in the subsequent process, and also cause the texture to harden during the dyeing process. . In addition, the fineness of each filament constituting the undrawn yarn is 1 after drawing.
It is preferably in the range of ~6 denier. If filament with a fineness of more than 6 denier is mixed, the texture of the resulting fabric will tend to be rough and hard.
In addition, if filaments with a fineness of less than 1 denier are mixed in, fuzz tends to occur and operability is impaired, which is not preferable. The reason for increasing the birefringence as the fineness decreases is to provide a natural color tone similar to that of spun yarn. Next, 5 and 8 are drawing rollers, 6 is a hot pin, and 7 is a hot plate. The undrawn yarn 2 is drawn between the drawing rollers 5 and 8 at a drawing ratio of 0.65 to 0.78 times the maximum drawing ratio. In this case, the temperature of hot pin 6
Tp (℃) and hot plate temperature TpL (℃)
must satisfy Tg−30≦Tp≦Tg+20, TpL<Tg+45. However, Tg is the glass transition temperature of the polyester filament. The glass transition temperature Tg was determined using a differential scanning calorimeter (DSC-1B model, manufactured by PerkinElmer) using a sample of 10 mg and a heating rate.
The value measured under the condition of 20°C/min was used as the standard.
Incidentally, the spinning speed of polyethylene terephthalate
Tg of undrawn yarn melt-spun at 1300 m/min is 74
It was warm at ℃. The maximum draw ratio here is yarn speed 150
m/min, temperature of hot pin (matte 30φ) 85℃,
Temperature of hot plate (aluminum length 100mm) 115
This is the draw ratio at break of undrawn yarn when drawn under the drawing conditions of °C. In the mixed filament yarn of the present invention, as described above, the filament with the smallest fineness has the minimum draw ratio at break, so this maximum draw ratio substantially corresponds to the draw ratio at break with the minimum fineness, and in reality, after drawing The maximum stretching magnification is defined as the magnification at which fluff begins to appear in the yarn. The stretching ratio of undrawn yarn 2 is set to the maximum stretching ratio of 0.65 to
The reason why it is limited to 0.78 times is to set the yarn strength and the degree of dyeing spots within an appropriate range. In other words, if the draw ratio is less than 0.65 times the maximum draw ratio of undrawn yarn, dyeing spots will become clear, but the strength of the yarn will be considerably reduced, making it easier for operational troubles to occur in the subsequent process, and the dyeing process will be delayed. This is because the texture becomes hard. On the other hand, if it exceeds 0.78 times, the strength of the yarn increases, but the non-uniformly stretched portion of the filament with large fineness decreases, and the dyeing spots become extremely unclear, making it impossible to produce a natural color tone similar to that of spun yarn. It disappears. The temperature of the hot pin 6 and the hot plate 7 is limited because these temperature effects, like the stretching ratio, strongly influence the strength of the yarn after stretching and the degree of uneven dyeing. That is, as the temperature Tp of the hot pin 6 is increased, the strength of the yarn after drawing increases, but the degree of dyeing spots decreases, and the temperature of the hot plate 7 increases.
As TpL increases, the strength of the yarn after drawing tends to decrease. In particular, the temperature effect of the hot pin 6 varies greatly depending on the glass transition temperature Tg of the polyester used, and when Tg is exceeded, the yarn strength increases rapidly, but the degree of dyeing spots also tends to become unclear rapidly. If the temperature exceeds Tg+20 (℃), it will not be possible to produce a spun yarn-like color tone. On the other hand, hot pin 6
If the temperature Tp of the hot plate 7 is lower than Tg - 30 (℃) or the temperature TpL of the hot plate 7 is higher than Tg + 45 (℃), the strength of the yarn after drawing will decrease significantly, causing operational trouble in post-processing. This is undesirable because it causes In addition, as for the method of wrapping the undrawn yarn 2 around the hot pin 6, it is preferable to wind it around the hot pin 6 once. The hot pin 6 has a great effect on the ease with which the undrawn yarn can be drawn, and a hot roller may be used instead. Next, FIG. 2 is a schematic side view of an apparatus that performs false twisting after stretching. This device is used to give a spun yarn-like color and texture with excellent bulk and less sliminess. In the figure, 10 is a heater, 11 is a false twisting device, 12 is a pull-out roller, 14 is a winding roller, and 15 is a package. Appropriate conditions for false twisting the yarn 9 after drawing are an overfeed ratio and temperature similar to the drawing and false twisting conditions for ordinary polyester filament yarns, or slightly lower overfeed ratio and slightly lower temperature conditions. The false twisting device 11 may be a pin type or a friction false twisting device. False twisting can be carried out continuously or discontinuously after drawing an undrawn yarn mixed with filaments of different fineness under the above-mentioned drawing conditions. The elastic recovery rate varies depending on the difference, and the larger the fineness, the more likely it is to cause sagging, which can cause fuzz when unraveling after being wound into a package cage.Therefore, so-called outdraw, which is a continuous process of false twisting after stretching, is used. False twisting is convenient and rational because the slack is absorbed by crimp. In addition, 16 is a fluid processing device, which increases the yarn strength by interlacing the filaments and improves the handleability in post-processing.
It is used to create loops and entanglements to make the texture more similar to that of spun yarn. Therefore, the fluid treatment device 16 may be provided after the device of FIG. 1 to treat the yarn. Next, the operation of the present invention will be explained. In FIG. 1, undrawn yarn 2 is unrolled from package 1, passed through guide 3 and tensor 4, and heated between drawing rollers 5 and 8 by hot pin 6 and hot plate 7. It is stretched and drawn out at a stretching ratio of 0.65 to 0.78 times the maximum stretching ratio. Temperature Tp of hot pin 6 in this case
(°C) and temperature TpL of hot plate 7 (°C)
When the glass transition temperature of polyester filament is Tg, Tg−30≦Tp≦Tg+20, TpL<
It is within the temperature range that satisfies Tg+45. In FIG. 2, the yarn 9 pulled out from the drawing roller 8 is heated by a heater 10, false-twisted by a false-twisting device 11, and sent out by a delivery roller 12 to a guide 1.
3 and the package cage 1 by the winding roller 14.
It is wound up in 5. If necessary, the fluid may be treated after exiting the delivery roller 12. Thus, according to the method of the present invention, the filament with the minimum fineness is drawn substantially uniformly in the length direction, and at least the filament with the maximum fineness has thick thick portions that are dyed randomly in the length direction. death,
A yarn containing a mixture of filaments having different properties is obtained. When this yarn is dyed using an uneven dyeing method, a natural color tone effect similar to that of spun yarn can be obtained. After knitting and weaving, heat treatment is performed to emphasize the difference in heat shrinkage, and a bulky fabric can be easily obtained. Furthermore, by false-twisting the obtained spun yarn-like yarn, a processed yarn with excellent bulkiness and less slimy feel and texture similar to that of spun yarn can be obtained. The fineness filaments are uniformly mixed, and the dyeing spots are more randomly distributed, resulting in a yarn with an extremely natural spun yarn-like color tone effect. Example 1 Spinning polyethylene terephthalate at a speed of 1300
Various undrawn yarns shown in Table 1 were produced by melt spinning at a speed of m/min.

[Table] Next, the two types of undrawn yarns mentioned above were drawn together in a stretching device, and the maximum stretching ratio of the undrawn yarns was 0.64, 0.68, 0.72,
After stretching at each stretching ratio of 0.79 times under the conditions of a hot pin temperature of 60°C and a hot plate temperature of 105°C, entangling treatment was performed using a fluid treatment device at an air pressure of 1.5 kg/cm ² G. The obtained threads were tube-knitted and dyed with disperse dyes, and the yarn strength, degree of uneven dyeing (color tone), and texture were evaluated, and the results are shown in Table 2 as 〇 (good), △ ( Somewhat bad), × (poor). In other words, the combinations of B+D and A+C that satisfy the strength, the degree of dyeing unevenness, and the texture after stretching are 1.4 deniers or more in fineness difference after stretching, and the stretching ratio is 0.68 times and 0.72 times the maximum stretching ratio of the undrawn yarn. It was twice as much.

【table】

[Table] Example 2 Undrawn yarns spun simultaneously at a spinning speed of 1300 m/min from adjacent spinning nozzles with different spinning hole diameters are aligned. From mixed filaments of different fineness of 218 denier/18 filament and 217 denier/36 filament. An undrawn yarn was obtained. The undrawn yarn was drawn and false-twisted using an apparatus as shown in Figure 2 under the following conditions, and then subjected to an air pressure of 1.6 using a fluid treatment apparatus.
The entanglement treatment was performed using compressed air of Kg/cm ² G. Stretching conditions: Hot pin temperature 60℃ Hot plate temperature 115℃ Stretching ratio
2.9 (0.70 times the maximum stretching ratio) False twisting processing conditions...Heater temperature 190℃ Overfeed ratio 0.85% False twist number 2450T/M Delivery roller surface speed
150m/min The resulting false twisted yarn has an average single fiber fineness of 4.2
It was a processed yarn with a total denier of 156 denier, which was a uniform blend of denier and 2.1 denier.
The processed yarn is used as the warp and weft of the fabric, and the warp density is 78.
Book/2.54cm, weft density 74 threads/2.54cm, oblique weave (2/
When weaving 2), there were almost no thread breakages and good weavability was demonstrated. The obtained gray fabric was scoured and relaxed in a boiling water bath containing a nonionic activator, preset, and then dyed at 120°C using a dispersed blended dye. The dyed and finished fabric was a bulky fabric with natural shading and uneven dyeing, an appearance very similar to the color tone of spun yarn, and no slimy feeling.

[Brief explanation of the drawing]

The figures relate to the present invention; FIG. 1 is a schematic side view showing an example of an apparatus for carrying out the invention; FIG. 2 is a schematic side view showing an example of an apparatus in which the apparatus of FIG. 1 is connected to a false twister. FIG. 2...undrawn yarn, 3...guide, 4...tensor, 6
...Hot pin, 7...Hot plate, 9...False twisting device.

Claims (1)

[Claims] 1. The maximum fineness and minimum fineness after stretching are at least
An undrawn yarn consisting of two or more types of polyester filaments that differ by 1.4 denier, the filament with the largest fineness accounts for at most 3/5 (weight ratio), and the birefringence increases as the fineness decreases. A spun yarn characterized by being drawn at a draw ratio of 0.65 to 0.78 times the maximum draw ratio of the yarn, and such that the hot pin temperature Tp (°C) and the hot plate temperature TpL (°C) satisfy the following conditions. Method of manufacturing yarn. (Tg-30≦Tp≦Tg+20 TpL<Tg+45 Tg...Glass transition temperature of polyester filament (°C)) 2. Production of spun yarn-like yarn according to claim 1, which involves false twisting the drawn yarn. Method. 3. A method for producing a spun yarn-like yarn according to claim 1 or 2, in which the yarn is continuously treated with a fluid.