JPS6231095B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention involves stretching a thermoplastic synthetic fiber multifilament undrawn yarn or semi-drawn yarn such as polyester, and then running it in contact with a heating element for a short period of time to cause heat shrinkage of random size and period along each filament. The present invention relates to a method for producing a bulky textured yarn by providing a yarn length difference or a loop, and then supplying the yarn to a fluid turbulence region to create a loop, slack, or entanglement. Conventionally, methods for producing bulky textured yarns as described above are known, as described in Japanese Patent Application Laid-Open No. 50-89659 and Japanese Patent Application Laid-Open No. 53-106842. The method described in Japanese Patent Application Laid-open No. 50-89659 is ``by bringing a thermoplastic multifilament yarn into contact with a heating element under a tension less than the heat shrinkage stress, a random pattern of size and period is generated along each filament of the yarn. A method of winding by intertwining the crimp and loops of individual filaments by applying crimp, heat shrinkage difference, yarn length difference, and loop, and then passing it through a fluid turbulence region without applying substantial tension. '', and the bulky yarn obtained by this method has higher bulkiness than multifilament simply treated with fluid turbulence. However, since this method is based on the use of pre-drawn thermoplastic multifilament yarn as a starting material, there are no problems with processing stability or quality that would be a problem if the process was continuous with the drawing process. Not discussed. That is, the drawn yarn as a starting material used in this prior art is usually drawn with a drawing device called a draw twister, and when wound up, it has a
The number of twists is 50 twists/m, and when such a drawn yarn is used as a starting material, the multifilament after drawing is sufficiently stabilized over time, so its behavior with respect to heat is sensitive. The ability to easily exhibit sufficient thermal shrinkage behavior when brought into contact with a high-temperature heating body under low tension, and the fact that the multifilament has a large number of twists in the length direction, improves the convergence between the filaments that make up the multifilament. When brought into contact with a high-temperature heating element under low tension, individual filaments may open on the heating element to promote uniform heat reception, or some filaments that do not come into contact with the heating element may float on the heating element. Stable processing is possible under a wide range of conditions because it prevents the formation of rough arch-shaped sagging, but the biggest drawback of these conventional techniques is that the drawing process and processing process are separated. Therefore, the production cost is high due to the human and material costs required in the drawing process and the cost of transporting raw materials from the drawing process to the processing process, and when feeding the pirn-wound drawn yarn to the processing process. In addition, it is necessary to control the unwinding tension due to the difference in the amount of winding between the surface layer and the inner layer of the pirt, and yarn breakage often occurs due to fluctuations in the unwinding tension of the pirn. On the other hand, as a method of applying non-uniform heat treatment in a processing process directly connected to the stretching process, there is
Although this is shown in Example 1 of Publication No. 106842, the stretching conditions are not specified, and therefore the stability of the running yarn on the heating element, the dyeing spots or the bulkiness of the obtained bulky processed yarn may be affected. There was an unstable aspect to it. The purpose of the present invention is to directly connect the drawing process and the processing process, and the temperature of the heating drawing pin and the temperature of the heating element in the processing process are important factors for stably producing bulky textured yarn of good quality. A method to solve the various problems that occur in the direct drawing processing process, save labor in the process, increase productivity, reduce costs, and stably produce bulky processed yarn with uniform quality. It provides the following configuration. That is, after stretching a thermoplastic synthetic fiber multifilament undrawn yarn or semi-drawn yarn at 400 m/min or less using a heated drawing pin, the yarn is then run in contact with a heating body for a short time to undergo non-uniform heat treatment, When subsequently supplying the fluid to the turbulent region, the temperature T ₁ (°C) of the heating stretching pin and the surface temperature of the heating element
This is a method for producing bulky textured yarn in which T ₂ (°C) is within the range shown in formulas (1) and (2) below. Tg+10< _T1 <Tg+50...(1) 145+5R< _T2 <250...(2) However, Tg: Glass transition temperature of the supplied yarn (℃) R: Excess supply rate of yarn to the heating element (%) ) Next, the present invention will be explained in detail using the drawings.
FIG. 1 is a process diagram showing one embodiment of the manufacturing method of the present invention. The birefringence taken out from a suitable package 1 is
The thermoplastic multifilament yarn A in a substantially untwisted, undrawn yarn or semi-drawn yarn state with a thickness of 0.100 (Δn) or less is a guide 2, a first feed roller 3, a heated drawing pin 4, a draw roller 5, The fluid passes through the fluid injection nozzle 6, the heating element 7, the first relaxation roller 8, the water supply guide 9, the compressed fluid turbulence nozzle 10, the second relaxation roller 11, and the additional oil roller 12, and is wound up by the winding machine 13, A package 14 is formed. The thermoplastic multifilament yarn A in an undrawn or semi-drawn state with a birefringence index of 0.100 (Δn) or less is passed once or twice to a drawing pin installed between the first feed roller 3 and the draw roller 5. It is wound and stretched so that the birefringence becomes 0.140 (Δn) or more while applying a tension gradient before and after the hot-stretching pin. However, if the temperature of the hot-stretching pin is too low, stretching unevenness occurs and processing This causes dyeing spots on the yarn, and the quality of the processed yarn deteriorates significantly. On the other hand, if the heated drawing pin temperature is too high, the occurrence of drawing spots due to insufficient heat reception will be eliminated, but the thermal shrinkage behavior will be insufficient when it comes into contact with the heating element 7 during the processing process, and processing stability will be significantly impaired. Difficult problems arise in terms of quality and processing stability, such as the inability to obtain a good bulky textured yarn. Therefore, in the present invention, the heated drawing pin temperature is
T ₁ (°C) must be in the range of Tg + 10 < T ₁ < Tg + 50 [Tg = glass transition temperature (°C) of supplied yarn (undrawn yarn or semi-drawn yarn)]. Further, in this case, the drawing speed needs to be 400 m/min or less, preferably 350 m/min or less, so that the quality and processing stability of the processed yarn can be satisfied. Furthermore, the orientation of the multifilament after stretching is set to a birefringence of 0.140 (Δn).
By doing so, sufficient thermal shrinkage behavior can be obtained upon contact with the heating body 7, and a good bulky textured yarn can be obtained. The drawn yarn that has passed through the draw roller 5 is not wound up and is continuously run in contact with the heating element 7 for a short time in an oversupplied state, causing random thermal shrinkage differences in size and period along the individual filaments of the yarn. ,
Crinkling, yarn length difference and loops are applied. on the other hand,
It is preferable to supply the yarn to the heating element 7 while applying vibration and entanglement to the multifilament or individual filaments using the fluid jet nozzle 6 just before the yarn is brought into contact with the heating element 7. That is, in the present invention, since a substantially non-twisted multifilament yarn is supplied onto the heating body, the convergence between the individual filaments constituting the multifilament is extremely low, and the yarn may come into contact with the heating body in an oversupplied state. When the individual filaments are opened on the heating element, uniform heat reception tends to proceed, and some filaments that do not come into contact with the heating element tend to rise and form coarse arch-shaped slumps, resulting in poor workability. The resulting stabilized processed yarn has the disadvantages of insufficient bulkiness and poor unwinding properties from the package, so the multifilament or individual filaments are vibrated by a fluid jet just before contacting the heating element. By applying this, the multifilament and each filament cause complex string vibrations, and this string vibration causes the multifilament and each individual filament to vibrate in an extremely short period.
In addition, contact and non-contact with the heating body are alternately repeated efficiently, and some of the filaments that make up the multi-filament progress to receive heat uniformly, and some of the other filaments float up.
It is possible to prevent the formation of coarse arch-like sagging. In this case, the degree of entanglement of yarns due to fluid flow is CF
The value is preferably 1.05 to 3.00. The above fluid injection nozzle 6 is, for example,
Those described in Japanese Patent No. 12230 can be used. Next, in the present invention, the stretched yarn is caused to run in contact with the heating element 7.
At this time, if the temperature of the heating element is low, the multifilament will not exhibit sufficient thermal shrinkage behavior, resulting in poor processing stability and insufficient bulkiness of the processed yarn. In addition, if the temperature of the heating element is too high, the processing stability and bulkiness of the processed yarn will improve, but some of the filaments will fuse on the heating element, and the dyeing capacity of the fused and non-fused areas will increase. Dyeing spots due to the difference are likely to occur, and the optimum temperature range of the heating element also changes depending on the overfeeding rate of yarn fed onto the heating element. As a result of intensive studies, the present inventor found that 145+5R<T ₂ <
250 (R= Yarn overfeed rate=
It has been found that it is necessary to set the speed in the range of draw roller speed - first relaxation roller speed / first relaxation roller speed x 100% T ₂ = heating element surface temperature (° C.). Next, in the present invention, the yarn that has been subjected to the non-uniform heat treatment by the heating element 7 is further subjected to the following process in a fluid turbulence region to make it bulky. That is, the yarn passed through the first relaxation roller 8 is compressed through the water supply guide 9 provided between the first relaxation roller 8 and the second relaxation roller 11 while maintaining an oversupply state between the two rollers. It leads to the fluid turbulence nozzle 10. The water supply guide 9 applies water to the yarns, improves the opening property of the multifilament, enhances the entangling effect in the fluid turbulence area, and increases the efficiency of loop generation caused by the kinetic energy of the fluid turbulence. Any material may be used as long as it is used for this purpose and can constantly apply water to the yarn. The compressed fluid turbulence nozzle 10 is capable of forming a turbulent region with compressed fluid, and is, for example, disclosed in Japanese Patent Publication No. 34-8969.
The nozzle and method shown in the publication can be adopted. The overfeed rate of the yarn supplied to the compressed fluid turbulent flow nozzle 10 may be any value as long as it is below the limit that allows it to be wound backward onto the first and second relaxation rollers, but From the viewpoint of bulkiness, 7% or more is desirable. The yarn that has passed through the second relaxation roller 11 is
It passes through the additional oil roller 12 for applying finishing oil agent and winds up the winder 1.
3 to form a package 14, and the process is completed. Addition of finishing oil is used to improve yarn unwinding from the package cage, reed wear during the weaving process, knitting needle wear during the knitting process, etc., but it may or may not be used depending on the purpose. good. As explained above, in the present invention, when the drawing process and the processing process are directly connected, the temperature of the drawing heating pin and the temperature of the heating element 7 are set within a certain range, thereby stabilizing bulky textured yarn of good quality. In addition to being able to omit the winding process after stretching, high-speed production is possible, reducing costs, and preventing problems such as yarn breakage due to fluctuations in unwinding tension. It has the effect that it can. Example Melt spinning polyethylene terephthalate,
By changing the winding speed, a multifilament consisting of 72 filaments in various undrawn or semi-drawn yarn states with different birefringence indexes is wound.
It was produced so that the denier after stretching to 0.160 to 0.170 (Δn) was 150 denier. The experiment was carried out in the manner shown in FIG. 1 using the above yarn. The heated drawing pin 4 has a metal satin finish with an outer diameter of 35 mm, the surface temperature is 110°C, the circumferential speed of the draw roller 5 is 300 m/min, the thread passage diameter of the fluid injection nozzle 6 is 13 mmφ, the length is 15 mm, and the compressed air injection hole diameter. 1.2mm
φ, the compressed air blowing pressure is 0.5 Kg/cm ² ·G, the heating element 7 is a metal matte surface finish with an outer diameter of 58 mmφ and the surface temperature is 210°C, and the thread between the draw roller 5 and the first relaxing roller 8 is Using the nozzle described in Figure 4 of USP 3545057 as the compressed air fluid turbulence nozzle 10 with a feed rate of 10% and a compressed air blowing pressure to the nozzle of 5.5
Kg/cm ²・G, the yarn overfeed rate between the first relaxation roller 8 and the second relaxation roller 11 is 15%, and the yarn overfeed between the second relaxation roller 11 and the winder 13 The rate was set to -6.5%. In addition, water supply guide 9
Apply 10c.c./min of water to the yarn with
2, 0.5% finishing oil was applied. Based on the above conditions, the heating drawing pin temperature, drawing speed, and heating element surface temperature were variously changed to investigate the running yarn stability on the heating element, the dyeing spots of the processed yarn, and the bulkiness of the processed yarn. It is shown in Table 3.

【table】

[Table] ○Good △Slightly poor ×Poor

[Glass transition temperature]

An absolutely dry sample of known weight is placed in a small container connected to a capillary tube, the space in the container is filled with mercury, the container is immersed in a glycerin heating medium, and the glycerin heating medium is gradually heated to cause the sample to expand. The value of the rise and fall of the mercury column in the capillary tube was read, and a temperature-specific volume curve was created from that value. The curved line that appeared near 70°C on the same curve was defined as the glass transition point, and the temperature at this time was defined as Tg (glass transition temperature). The Tg of the undrawn yarn used in the present invention was measured by the above method and was 73°C.

[Brief explanation of the drawing]

FIG. 1 is a process diagram showing one embodiment of the manufacturing method of the present invention. [Description of main symbols], 1: package, A: multifilament yarn, 2: guide, 3: first feed roller, 4: heated drawing pin, 5: draw roller, 6: fluid injection nozzle, 7: heating element, 8: 1st
Relaxation roller, 9: Water supply guide, 10: Compressed fluid turbulence nozzle, 11: Second relaxation roller,
12: Adding oil roller, 13: Winding machine, 14: Package cage.

Claims (1)

[Claims] 1 Thermoplastic synthetic fiber multifilament undrawn yarn or semi-drawn yarn is heated to 400 mm using a heated drawing pin.
After stretching at a speed of m/min or less, the temperature T ₁ (°C) of the heated stretching pin and the surface of the heating body are determined. Temperature T ₂ (℃)
A method for producing bulky textured yarn, characterized in that: is within the range shown by the following formulas (1) and (2). Tg+10< _T1 <Tg+50...(1) 145+5R< _T2 <250...(2) However, Tg: Glass transition temperature of the supplied yarn (℃) R: Excess supply rate of yarn to the heating element (%) )