JPS6233331B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing with high productivity a velour-like polyamide crimped yarn which is particularly suitable as a pile yarn for velor-like cut carpets. In recent years, the fashionability of general household carpets has become important, and velour-like cut carpets have recently become particularly popular. There are several high requirements for such velor-like carpets. Among these, the most important factors are the crimp rate and crimp fastness.If the crimp rate is high, when the carpet is made into a carpet and subjected to heat treatment such as piece dyeing, large crimp will occur in the pile and the carpet will have a hard texture. It looks bad. In other words, a low crimp rate is required because the velor feel will be lost and the product value will be lowered. Furthermore, if the durability of the cut pile is low, the pile will tend to sag after being used for a short period of time, so the pile is required to have high robustness, that is, high crimp robustness. Furthermore, since dyeing spots are easily noticeable in velor-like cut carpets, level dyeing of the pile yarn is particularly required. In order to produce polyamide crimped yarn with the above characteristics required as pile yarn for velour-like cut carpet, conventionally, the crimped yarn is steamed for 30 to 60 minutes under low or free tension in a separate process. A method of heat treatment is used.
Although this method generally satisfies the characteristics required for velor-like cut carpet, it has the drawback that it is very disadvantageous in terms of equipment productivity, that is, manufacturing cost, because it is performed in a separate process. Furthermore, there is a drawback that spots are more likely to occur as the number of steps increases. On the other hand, fluid crimping technology has progressed rapidly in recent years and high-speed crimping is now possible, resulting in the so-called direct spinning draw crimping process (SDT process) in which the spinning, drawing, and crimping processes are connected. The production of crimped yarn is now underway. However, the crimped yarn obtained by this method does not satisfy the above characteristics and is therefore unsuitable as a pile yarn for velor-like carpets. The main object of the present invention is to directly spin, draw, and crimp a velour-like polyamide crimped yarn, which is suitable as a pile yarn for velor-like cut carpets and has low crimping and high crimp fastness, by directly linking spinning, drawing, and crimping. (SDT process) to manufacture with high productivity. In view of the above-mentioned objective, the present inventors conducted intensive studies to produce a velour-like polyamide crimped yarn suitable as a pile yarn for velor-like cut carpets, and as a result, crimped it by a direct spin-draw-crimp (SDT) process. The crimped yarn is continuously introduced into a heat treatment zone consisting of a pipe-shaped chamber, heated or saturated steam is supplied to the heat treatment zone, and the crimped yarn running at high speed is heated in an extremely short time of 0.1 seconds or less. We have invented a method of reducing the crimp rate and heat setting by heat treatment for a period of time. However, in this method, a certain amount of processing time is required to perform steam heat treatment in a heat treatment zone consisting of a pipe-shaped chamber to detect crimp, reduce the crimp rate of the yarn, and heat set it. If this is attempted to be carried out in a very short period of time, there is a limit to the effectiveness, and it is not possible to obtain a pile yarn that fully satisfies the crimp characteristics as a pile yarn for velor-like cut carpets. Therefore, as a result of further study by the present inventors, the crimped yarn to be supplied to the pipe-shaped steam chamber was reduced in crimp in advance, and the processed yarn with a low crimp rate was reheated in the pipe-shaped steam chamber. It was discovered that by carrying out the above steps, a polyamide crimped yarn having a low crimp rate and high crimp fastness can be obtained, which is suitable as a pile yarn for velor-like cut carpets, and has thus arrived at the present invention. That is, in the present invention, when producing a polyamide crimped yarn by a direct spinning draw-crimping method,
After preheating the yarn immediately after drawing, the yarn is injected from a nozzle together with a heated compressed fluid and collided with a fluid-permeable collision surface to achieve a crimp ratio (TCo) of 5.0.
12.0% of the crimped yarn, the yarn is then continuously introduced into a pipe-shaped chamber without being wound once, and heat-set with heated steam to determine the crimp fastness (TC ₅₎ . /TC ₀ ) is wound as a processed yarn of 0.6 or more, thereby producing a velor-like polyamide crimped yarn suitable as a pile yarn for velor-like cut carpets. Hereinafter, the present invention will be explained in detail with reference to the drawings. FIG. 1 is a schematic diagram of a direct spinning drawing and crimping apparatus showing a preferred embodiment of the present invention. In the figure, a polyamide yarn Y spun from a spinning tube 1 is oiled by an oiling roller 2, and It is taken off by a taking roller 3. It is then wound several times around a preheating roller 4 and a separating roller 4', where it is preheated to about 50° C. and led to a stretching zone. In the stretching zone, 3 to 5
At the same time as the yarn is stretched twice, the yarn is heat-treated and preheated for crimping (to about 180°C or higher). The yarn is then guided to a heated fluid injection nozzle 6, and is injected from the nozzle together with a fluid, and collides with an air-permeable collision surface 7 provided near the fluid injection hole, causing buckling or taslan-like crimp. The mold is done. The crimped yarn subsequently passes through a guide 8 and is taken off at a constant speed by a processing take-off roller 9 and a separation roller 9'. Next, the yarn is introduced into a pipe-shaped steam chamber 10, and after being heat-set by heated steam in the chamber 10, it is passed through a draft roller 11 and a separation roller 11'.
It is wound and drafted, cooled, and wound onto a bobbin 13 by a winder 12. In the present invention, in such a series of steps,
The crimp rate (TCo) of the yarn introduced into the pipe-shaped steam chamber 10 is particularly important, and the crimp rate (TCo) of the crimped yarn fed therein is set to 5 to 12%.
It is important to adjust the amount within a range of (particularly 6 to 10%). If the crimp rate of the yarn supplied to the tubular chamber 10 is too high, exceeding 12%, extreme conditions may be required to cause crimp development and heat fixation in the tubular chamber 10. For example, steam must be used at high temperature and pressure.
In this case, fusion occurs between the single filament yarns before the crimped yarn is heat-set, and when a velor-like cut carpet is made, the spreadability between the single yarns is poor and the velor feel is lost. . In this way, in order to obtain a yarn with a desired crimp ratio (TCo) of 5 to 12% in crimping, it is effective to adjust the overfeed rate of the yarn during crimping. That is, in the crimping process, the heated fluid jet nozzle 6 and the air permeable collision surface 7 cause the material to become crimped while causing contraction between the stretching roller 5 and the processing take-off roller 9. The crimp rate (TC ₀ ) of the crimped yarn can be controlled by the amount of slack in the yarn ejected from the nozzle. If the overfeed rate during processing (the overfeed rate of the drawing roller 5 with respect to the processing take-up roller 9) is high, a highly crimped yarn can be obtained. A crimped thread is obtained. In the present invention, by setting the overfeed rate to 40% or less, particularly 15 to 30%, a desired crimp rate (TC ₀ ) can be achieved. The fluid ejecting nozzle 6 used here may be of a turbulent flow type or a laminar flow type, but in particular when yarn convergence (interlacing) is not required,
The laminar flow type has excellent high-speed machining properties. The fluid supplied to these nozzles 6 is suitably high temperature air or steam. Needless to say, in the case of the latter laminar flow type nozzle, impact buckling becomes dominant when the crimped material is injected onto a permeable impact surface. The collision surface 7 is preferably breathable so that almost all of the fluid can be separated therefrom, but if the mesh of the collision surface is made rough, for example, single yarns will get caught. Therefore, it is necessary to select a collision surface of the mesh that has good fluid permeability and is free from single threads. According to the research of the present inventors, it is optimal to use a wire mesh of 20 to 100 meshes (particularly 30 to 40 meshes) as the breathable collision surface 7.
is provided so that the angle θ with respect to a plane perpendicular to the direction in which the yarn is ejected from the nozzle 6 is 10 to 35 degrees (in particular, 15 to 30 degrees), and as shown in the figure, the running direction of the yarn is approximately at the collision surface 7. Preferably, the angle is changed by 90°. Further, the thread running distance from the outlet of the nozzle 6 to the collision surface 7 is suitably within 10 mm. The crimped yarn thus obtained is taken up from the roller 9 and passed directly through the winder 12 to the bobbin 13.
As mentioned above, even if the yarn is wound with a low crimp, the heat setting is insufficient and only a low crimp fastness can be obtained. Therefore, when the yarn is used as a pile yarn for a velor-like cut carpet, there is a drawback that the pile is not durable. Therefore, in the present invention, the crimped yarn is further continuously guided into the pipe-shaped steam chamber 10, and a draft roller 11 applies a slight draft (loop formed during processing removes sagging). However, if the crimp is developed and heat-set by heating or saturated steam treatment within the chamber 11, the crimp fastness can be improved. At this time, heat setting in the pipe-shaped chamber 10 is preferably performed in a relatively closed system in order to increase its efficiency. It is important to select an appropriate material according to the fineness De (denier). According to research by the present inventors, the inner diameter (dmm) of the yarn introduction hole and the discharge hole of the pipe-shaped chamber 11 is 0.023√≦d≦0.023√+0.5 with respect to the fineness (De) of the crimped yarn. However, it is preferable to satisfy 400≦De≦6000; if d is too small, the yarn will not run smoothly, and if d is too large, it will be difficult to perform sufficient heat setting due to steam leakage. When heat setting the pipe-like chamber 10, the crimped yarn is set with an overfeed of 0 to 10%, which improves the setting property and improves the dimensional stability of the crimped yarn. It is necessary to heat-set the crimped yarn sufficiently in this pipe-shaped chamber 10 so that the crimp fastness (TC ₅ /TC ₀ ) of the yarn after setting is 0.6 or more. If the crimp fastness is less than 0.6, when a velor-like cut-pile carpet is made, the crimp of the pile is likely to become flattened and the durability of the carpet deteriorates. The crimp rate (TC ₀ ) of the crimped yarn heat-set in the pipe-shaped chamber 11 is 4.5 to 10.0% (especially 4.5%).
8.0%), and those having such a crimp ratio can constitute an excellent velor cut carpet. In other words, if the crimp rate exceeds 10%, the carpet will have a strong felt feel, and if the crimp rate is less than 4.5%, the bulkiness will be poor, and both are unsuitable as pile yarns for velor-like cut carpets. be. The yarn to which such a method of the present invention is applied is not limited as long as it is a polyamide multifilament yarn, but among them, yarns having a denier of 400 to 6000 de after crimping are preferred.
Further, the multifilament yarn may be a mixture of single fibers having different dyeability, filament cross-sectional shape, denier, etc. The single fibers preferably have a circular cross section such as trilobal, Y-shape, triangular, or quadrangular. According to the present invention as described above, it is possible to produce velor-like polyamide crimped yarn with a low crimp rate and high crimp fastness, which is suitable as pile yarn for velor-like cut carpet, in one process at high speed. Moreover, the resulting crimped yarn has fewer spots,
It also has excellent handling properties. Hereinafter, the present invention will be explained in detail with reference to Examples and Comparative Examples. In addition, "crimping rate (TC ₀ )", "crimping fastness (TC ₅ /TC ₀ )", and "overfeed rate (OF)" referred to in the present invention are values defined as follows. (1) Crimping rate (TC ₀ ) A certain length of crimped yarn was taken, and this sample was treated in boiling water for 20 minutes under no load, and after drying.
The length when a load of 0.1 g/de is applied is l ₁ ,
Next, if the length when a load of 2 mg/de is applied is l ₂ , the value is calculated by the following formula. Crimp ratio (TC ₀ )=l ₁ −l ₂ /l ₁ ×100 (%) (2) Crimp fastness (TC ₅ /TC ₀ ) In the method for measuring the crimp ratio (TC ₀ ), 20
During boiling water treatment for 1 minute, a load of 5 mg/de was applied and the TC ₅ was determined in the same manner.
TC ₅ is calculated from the above TC ₀ using the following formula. Crimp fastness (TC ₅ /TC ₀ ) = TC ₅ /TC ₀ (3) Overfeed rate during crimping (OF) The speed of the stretching rollers 5 and 5' in Fig. 1 is V ₅ , and the take-up roller When the speed of 9 is set as V ₉ , it is obtained by the following formula. Overfeed rate (OF) = V ₅ - V ₉ /V ₉ ×100 (%) Examples 1 to 7, Comparative Examples 1 to 5 Direct spinning drawing crimping apparatus equipped with a heated fluid jet shown in FIG. After spinning polyε-caproamide, it was stretched without winding.
1300de/68fil nylon 6 multifilament yarn was continuously crimped. At this time, from the nozzle outlet of the heated fluid jet,
A wire mesh of 40 meshes was installed at a position of mm so that the angle θ was 25 degrees, and as shown in FIG. 1, the thread ejected from the nozzle collided with the wire mesh and was separated from the fluid. Table 1 shows the processing conditions at this time and the crimp characteristics of the obtained nylon 6 crimped yarn. In addition, the first
Comparative Examples 1 to 3 in the table are cases in which a pipe-shaped chamber is not used, and Comparative Examples 4 to 6 are cases in which the crimp rate before entering the pipe-shaped chamber is too high, and the carpet performance is not satisfactory in either case. do not have. On the other hand, in the crimping process, the crimping was reduced in advance by low overfeed rate processing, and then reheating was performed using a pipe-shaped steam chamber (Examples 1 to 7), resulting in a velor-like cut carpet. Performance is good when In addition, Examples 3 and 7 have crimp ratios (TC ₀ ) after heat setting.
This is an example of a carpet that is so low that it lacks bulkiness when used as a carpet. 【table】

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a direct spinning drawing and crimping apparatus showing one embodiment of the present invention, in which 1 is a spinning tube, 5 is a
6 is a heated stretching roller; 6 is a heated fluid injection nozzle;
7 indicates a fluid-permeable impingement surface, and 10 indicates a pipe-shaped steam chamber.

Claims (1)

[Claims] 1. When producing polyamide crimped yarn by the direct spinning draw-crimping method, the yarn immediately after being stretched is preheated, and then the yarn is injected from a nozzle together with a heated compressed fluid to cause fluid permeation. A crimped yarn with a crimp ratio (TCo) within the range of 5.0 to 12.0% is formed by impacting the yarn against a collision surface, and then the yarn is continuously fed into a pipe-shaped chamber without being wound once. A method for producing a velor-like polyamide crimped yarn, which is characterized in that it is introduced, heat set with heated steam, and wound as a crimped yarn with a crimp fastness (TC ₅ /TCo) of 0.6 or more. 2. The overfeed rate of the yarn is set to 40% or less when the yarn injected from a nozzle together with heated compressed fluid collides with a fluid-permeable collision surface to perform the crimping process. A method for producing velour-like polyamide crimped yarn. 3. The velor according to claim 2, wherein a wire mesh of 20 to 100 meshes is used as the fluid-permeable collision surface, and the collision surface is set at an angle of 10 to 35 degrees with respect to a plane perpendicular to the yarn jetting direction. A method for producing crimped polyamide yarn. 4 The crimp rate (TCo) of the yarn is reduced by heat setting using heated steam inside the pipe-shaped chamber.
Claim 1, which adjusts to 4.5 to 10.0%;
The method for producing a velour-like polyamide crimped yarn according to item 2 or 3.