JPS6231096B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention involves drawing 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 time to produce random thermal shrinkage differences in size and period along each filament. The present invention relates to a method for manufacturing a bulky textured yarn by providing yarn length differences or loops, and subsequently supplying the yarn to a fluid turbulence region to provide loops, slack, or entanglement. Conventionally, methods for producing bulky textured yarns such as those described above have been disclosed in Japanese Patent Application Laid-open No. 50-89659 and Japanese Patent Application Laid-Open No. 53-106842.
The ones described in the No. 1 gazette, etc. are known. The method described in Japanese Patent Application Laid-open No. 50-89659 is based on ``a thermoplastic multifilament yarn that is brought into contact with a heating element under a tension less than the heat shrinkage stress, thereby creating random patterns of size and period along each filament of the yarn. After giving the filament a certain amount of crimp, heat shrinkage difference, yarn length difference, and loop, the filament is passed through a fluid turbulence region without applying any tension, so that the crimp and loops of each filament are entangled with each other. The bulky yarn obtained by this method has higher bulkiness than that obtained by simply subjecting multifilament to fluid turbulence treatment. However, this method assumes that pre-drawn thermoplastic multifilament yarn is used as the starting material.
There is no discussion at all about processing stability and quality problems that would be an obstacle when continuous with the stretching process. That is, the drawn yarn as the starting material used in this prior art is usually drawn with a drawing device called a draw twister, and when it is 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. Since the formation of coarse arch-shaped sag is prevented, stable processing is possible under a wide range of conditions. However, the biggest drawback of these conventional technologies 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 the need to feed the drawn yarn after pirn winding to the processing process. In this case, it is necessary to control the unwinding tension due to the difference in the winding amount between the surface layer and the inner layer of the pirt, and furthermore, yarn breakage often occurs due to fluctuations in the unwinding tension of the pirt. 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 it 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 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 surface temperature of the heating roller in the drawing process and the temperature of the heating element in the processing process are important factors for stably producing bulky textured yarn of good quality. In addition to solving various problems that occur in the direct drawing processing process, we aim to save labor in the process, increase productivity, reduce costs, and stably produce bulky processed yarn with uniform quality. The present invention provides a method and has the following configuration. That is, thermoplastic synthetic fiber multifilament undrawn yarn or semi-drawn yarn is heated using a heating roller.
After stretching at a speed of 500 m/min or less, the heating roller surface temperature T ₁ (°C) and the heating element surface temperature are set as follows: 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<T ₁ <Tg+40 ……………(1) 145+5R＜T ₂ <250 ………(2) However, Tg = Glass transition temperature of the supplied yarn (°C) R = Temperature to the heating element Yarn excess supply rate (%) 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 the state of substantially untwisted undrawn yarn or semi-drawn yarn with a thickness of 0.100 (Δn) or less is transported by a guide 2, a first feed roller 3, a heating roller 4, a draw roller 5, and a fluid jet. nozzle 6, heating element 7, first relaxation roller 8,
It passes through the water supply guide 9, the compressed fluid turbulence nozzle 10, the second relaxation roller 11, and the additional oil roller 12, and is then wound up by a winder 13 to form a package 14. The thermoplastic multifilament yarn A in an undrawn or semi-drawn state with a birefringence index of 0.100 (Δn) or less passes through the first feed roller 3 and then enters the heating roller 4 where it is sufficiently heated. After performing this, the heating roller 4 and the draw roller 5
the birefringence without giving a tension gradient between
Although it is stretched to 0.140 (Δn) or more,
If the temperature of the heating roller 4 is too low, stretching irregularities will occur, which will cause dyeing irregularities in the processed yarn, and the quality of the processed yarn will deteriorate significantly. On the other hand, if the temperature of the heating roller is too high, the occurrence of stretching unevenness 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 temperature of the heating roller is
T ₁ (°C) needs to be in the range of Tg-10<T ₁ <Tg+40 (Tg=glass transition temperature (°C) of supplied yarn (undrawn yarn or semi-drawn yarn)). Further, in this case, the drawing speed needs to be 500 m/min or less, preferably 450 m/min or less, so that the quality and processing stability of the processed yarn can be satisfied. Further, by setting the orientation of the multifilament after drawing to a birefringence of 0.140 (Δn) or more, sufficient thermal shrinkage behavior upon contact with the heating body 7 can be obtained, 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. , crimping, 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 progress, and some filaments that do not come into contact with the heating element tend to float up and form coarse arch-shaped sag, resulting in poor workability. The resulting stable textured yarn has the drawbacks of insufficient bulk and poor unwinding properties from the package. By applying vibration, the multifilament and individual filaments produce complex string vibrations,
Due to this string vibration, the multifilament and the individual filaments are brought into contact with the heating element and non-contact alternately in an extremely short and efficient manner, and some of the filaments making up the multifilament are uniformly It is possible to prevent heat reception from progressing, other filaments from lifting up, and formation of coarse arch-shaped sag. 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 also due to the overfeeding rate of yarn fed onto the heating element.
The optimum temperature range of the heating element varies. 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 within 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 non-uniformly heated by the heating element 7 is further passed through the following process in a fluid turbulence region to be bulked. That is, the yarn passed through the first relaxing roller 8 is compressed through the water supply guide 9 provided between the first relaxing roller 8 and the second relaxing roller 11 while maintaining an oversupply state between the first relaxing roller 8 and the second relaxing roller 11. It leads to the fluid turbulence nozzle 10. Water supply guide 9
The purpose of this method is to add water to the yarns to improve the opening properties of the multifilament, thereby increasing the entanglement effect in the fluid turbulence region, and increasing the efficiency of loop generation caused by the kinetic energy of the fluid turbulence. Any material may be used as long as it can constantly apply water to the yarn. The compressed fluid turbulence nozzle 10 is capable of forming a turbulent region with compressed fluid, and for example, the nozzle and method disclosed in Japanese Patent Publication No. 34-8969 can be adopted. The overfeeding rate of the yarn supplied to the compressed fluid turbulence nozzle 10 may be any value as long as it is below the limit of being reversely wound around the first and second relaxation rollers; From the viewpoint of performance, 7% or more is desirable. The yarn that has passed through the second relaxation roller 11 passes through an additional oil roller 12 for applying finishing oil, and then passes through a winding machine 1.
3 to form a package 14, and the process is completed. Adding 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. It's okay. As explained above, in the present invention, when the drawing process and the processing process are directly connected, by setting the temperature of the heating roller and the temperature of the heating element 7 within a certain range, it is possible to stably produce 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 Polyethylene terephthalate was melt-spun and wound by changing the winding speed to produce a multifilament consisting of 72 filaments in various undrawn or semi-drawn states with different birefringence indexes, and a birefringence index of 0.160.
It was produced so that the denier after stretching to 0.170 (Δn) was 150 denier. The experiment was carried out in the manner shown in FIG. 1 using the above yarn. The surface temperature of the heating roller 4 is 85°C, the circumferential speed of the draw roller 5 is 370 m/min, the thread passage diameter of the fluid injection nozzle 6 is 1.3 mmφ, the length is 15 mm, and the compressed air injection hole diameter is 1.2 mm.
φ, the compressed air blowing pressure is 0.5Kg/cm ² G, the heating element 7 is a metal matte surface finish with an outer diameter of 50mmφ, the surface temperature is 210℃, and the temperature between the draw roller 5 and the first relaxation roller 8 is Using the nozzle described in Fig. 4 of USP3545057 with a yarn oversupply ratio of 10% and a compressed air fluid turbulence nozzle 10, the compressed air blowing pressure to the nozzle was 5.5 kg/
cm ² ·G, the yarn overfeed rate between the first relaxing roller 8 and the second relaxing roller 11 is 15%, and the yarn feeding rate between the second relaxing roller 11 and the winder 13 is - It was set at 6.5%. In addition, water supply guide 9 is 10c.c./
Apply water of min. to the yarn, and add 0.5
% finishing oil was applied. Based on the above conditions, the heating roller temperature, drawing speed, and heating element surface temperature were variously changed to examine the running yarn stability on the heating element, dyeing spots of the processed yarn, and bulkiness of the processed yarn. Shown in the table.

【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 bending point that appeared near 70℃ on the same curve is defined as the glass transition point, and the temperature at this point is defined as the glass transition point.
Tg (glass transition temperature). When the Tg of the undrawn yarn used in the present invention was measured by the above method, it 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. [Explanation of main symbols] 1: package, A: multifilament yarn, 2: guide, 3: first feed roller, 4: heating roller, 5: draw roller, 6: fluid jet 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)

[Scope of Claims] 1 Thermoplastic synthetic fiber multifilament undrawn yarn or semi-drawn yarn is processed for 500 m/s using a heating roller.
After stretching at less than 10 min, the heating roller surface temperature T ₁ (°C) and the heating element surface temperature T ₂ are continuously passed in contact with a heating element for a short period of time for non-uniform heat treatment, and then supplied to a fluid turbulence region. A method for producing bulky textured yarn, characterized in that (°C) is within the range shown in formulas (1) and (2) below. Tg-10<T ₁ <Tg+40 ...(1) 145+5R<T ₂ <250 ...(2) However, Tg: Glass transition temperature of the supplied yarn (℃) R: Excess supply rate of yarn to the heating element (%)