JPS6315226B2 - - Google Patents

Description

[Detailed description of the invention]

In the present invention, when a stretchable bulky yarn made of polyamide such as nylon is dyed after being wound into a cheese state, the CR value (CR value refers to the elastic recovery rate and the measurement method is in accordance with JISL1090) is compared to that before dyeing. The present invention relates to a winding method for obtaining a package for cheese dyeing with almost no decrease in the quality of the package. Generally, bulky textured polyamide synthetic fiber yarns such as nylon have extremely excellent elastic properties, and it is well known that yarn-dyed yarns that take advantage of these properties are used as final products for socks, swimwear, etc. In this case, the final product is required to have elasticity before dyeing, so when dyeing is performed, it is recommended to wind the yarn into a skein from a cheese-like package after the expansion and bulking process, and then dye it in the skein. Currently, it has become mainstream. However, in recent years, due to the desire to shorten the process, attempts have been made to omit this skein winding step and directly dye the cheese in the rolled cheese state after bulk processing.
When dyed directly with cheese, the stretch properties tend to be significantly lower than those that are skeined and dyed, and for this reason cheese dyeing has not been adopted for polyamide stretchable bulky yarns such as nylon. The inventor investigated the cause of this problem and found the following. In other words, when dyeing polyamide synthetic fibers, it is usually impossible to dye unless the yarn temperature is raised to about 100℃, and in particular, 100℃ is a temperature that is stable at the boiling point of water, so it is difficult to dye the dye solution. It is used at this temperature. However, at this temperature of 100°C, the yarn undergoes heat shrinkage (here, heat shrinkage is defined as the case where the fiber itself contracts in the fiber axis direction due to heat) and the latent crimp of the stretchable bulky yarn. However, in the case of a cheese-like package, the yarn is wrapped around the winding tube and the wound lower yarn layer. subject to restrictions,
The yarn cannot freely undergo thermal contraction, so the yarn itself is subjected to heat treatment under internal stress, just as the yarn is subjected to heat treatment under constant tension. It exhibits a heat shrinkage behavior of
For this reason, it is thought that the CR value decreases. On the other hand, when the yarn is dyed after being wound into a skein, there is no winding tube and the yarn itself can freely shrink due to heat, so there is no room for internal stress to occur in the yarn, and therefore the CR value is It seems that there will be almost no decline. Therefore, the present inventor has conducted intensive studies on a method of winding a package for cheese dyeing that eliminates the drawbacks of the conventional technology, is stable in terms of quality, and can contribute to streamlining process reduction, and as a result, has arrived at the present invention. be. The focus of the present invention is to maintain the same elastic properties of bulky processed yarns of polyamide synthetic fibers such as nylon after dyeing as before dyeing. As a result of considering the method of winding cheese with a focus on preventing the CR value from decreasing before and after dyeing by pre-heat shrinking the cheese-like package before dyeing, we found that conventional cheese-like package winding It was found that the objective could be achieved by selecting conditions that were not used at all in the method. That is, according to the present invention, it is possible to obtain a package for cheese dyeing in which the CR value after dyeing is almost unchanged from that before dyeing only in a region where the following two conditions are satisfied at the same time. The polyamide stretchable bulky yarn is pulled out from the yarn supply package using a nip roller and overfeeded at a speed faster than the winding speed.
When winding into a cheese-like package, the overfeed should be in the range of 50% to 200%. A heater installed between the knit roller and the winding device raises the yarn temperature to a range that satisfies the following conditions, causing latent crimp in the yarn, causing thermal contraction, and reducing slack in the yarn due to overfeed. Absorb and roll into a cheese shape under no tension. T＞t＞(0.4F+40)℃ However, T: Heat-set yarn temperature during bulk processing of supplied bulky yarn (℃) t: Yarn temperature (℃) F: Overfeed rate (%) More details about these conditions Regarding the first condition, when bulky textured yarn is generally overfeeded and wound, the overfeed rate is about 10 to 25%, which is the limit for winding.
The reason for this is that if it is 25% or more, the thread between the delivery roller and the winding device becomes too loose and sag, causing the thread to wrap around the delivery roller. Therefore, winding is impossible even if only the conditions of the present invention are applied, and the winding itself cannot be achieved unless the conditions of the present invention are combined. Next, regarding the second condition, if the yarn temperature is higher than the heat-set yarn temperature during the bulking process in the previous process, internal stress relaxation of the yarn itself will occur, resulting in yarns with different quality characteristics, which is undesirable. Therefore, the temperature must be lower than the heat-setting yarn temperature in the previous step. In addition, if the lower limit of the yarn temperature is too low, the latent winding of the stretchable bulky yarn will not be sufficiently developed and thermal contraction will not occur. Generally, thermal contraction hardly occurs at heater temperatures of 60°C or less. Therefore, 60°C or higher is preferable, but the lower limit of this yarn temperature range is correlated with the overfeed rate. Also, before and after staining
In the range where the CR value decreases by about 10%, the yarn temperature is 100.
~120°C with an overfeed of around 150% is most preferred. The setting of these conditions must be determined based on the commercial value of the processed yarn obtained. However, in any case, within the above condition range, no matter what combinations are used, the CR values before and after cheese staining are within a range that has almost no practical problems.
Stable staining is possible. The relationship between these conditions will be explained with reference to the drawings. Figure 1 is a graph showing the conditions of the method of the present invention, with the overfeed rate on the horizontal axis and the yarn temperature on the vertical axis. The winding conditions are within the shaded area. Next, the embodiment of the present invention will be explained in detail with reference to the drawings. Figure 2 shows an example of an apparatus for carrying out the method of the present invention. 2 is a guide, 3 is a nip roller, and the nip roller consists of a rubber apron 3c wound around a pair of rollers 3a and 3b so as to be able to circulate, and a feed roller 3d against which the apron 3c is elastically pressed. This pulls out the yarn Y from the supply package 1 and actively sends it out to the winding device 8 (described later). 4 and 6 are guides, and 5 is a heater for heating the yarn Y, and the heater may be a contact type or a non-contact type. In the case of a contact type heater, it is preferable because it has good thermal efficiency, but it is preferable to use one with a surface roughness of 1S or more in consideration of frictional resistance between the welding surface of the heater and the yarn.
Furthermore, since the yarn must always be in contact with the surface of the heater 7, the guides 4 and 6 must be eccentric from the welding surface of the heater. On the other hand, in the case of non-contact heaters, for example, the inner diameter of the tube heater is preferably smaller from the viewpoint of thermal efficiency and temperature uniformity, but since the yarn is fed in a relaxed state, there is an increased chance of contact friction with the inner wall of the tube heater. I don't like it. In any case, the conditions such as the type, temperature, and length of the heater should be determined as appropriate, taking into consideration the type of yarn, fineness, yarn speed, etc., as long as the yarn can be heated within the range of the above conditions. Can be done. Reference numeral 8 denotes a winding device of a surface friction drive type, which comprises a traverse guide 7, a winding drum 9, and a cradle 10. The cradle 10
The winding tube 11 is attached to a slide shaft 12 that slides inside a hollow tube 13 so that the shaft center moves horizontally with respect to the winding drum 9, and the lower end thereof supports a weight 15. A hanging wire 14 is attached. This weight 15 determines the contact pressure between the winding drum 9 and the package formed in the winding tube 11, and the contact pressure can be determined by adjusting the weight appropriately depending on the type of yarn to be wound. You can choose by changing. Note that 16 is a pulley. An example of an apparatus for carrying out the method of the present invention is configured as described above, in which yarn Y is fed from supply package 1 wound with crimpable bulky yarn to knit roller 3.
It is pulled out by the winding device 8 and sent out at a faster speed than the winding speed of the winding device 8, thereby being overfeeded. This overfeed amount falls within the above-mentioned conditions. After that, the yarn Y is placed in the heater 5.
Run the vehicle while heating it within the range of conditions. In this heater 5 section, the yarn is relaxed due to overfeed, and the relaxed state causes sag in a range exceeding the curling ability of the yarn at room temperature, but when heated by the heater 5, the elastic bulky yarn is As a result, the slack yarn Y is thermally shrunk, and the yarn Y is prevented from slacking between the nip roller 3 and the winding device 8, and the yarn Y is prevented from sagging when it is conventionally wound around the winding roller. This solves the problem of not being able to wind it up. Next, a slight contact pressure (around 200g) is applied with the winding device 8.
is applied while winding with a constant contact pressure from the beginning to the end of the winding. FIG. 3 shows another example of an apparatus for carrying out the method of the present invention, in which the supply package is one in which the yarn is twisted by a double twisting machine after bulking. Also, almost the same effect as in the case of FIG. 2 described above is achieved. (Example 1) Yarn type nylon 6670d/24f, double yarn of stretchable bulky yarn with a heat-set yarn temperature of 210° during false twisting.
A yarn having a twist of 100 T/M was used, and the yarn was wound at a feed speed of 200 m/min using a nip roller and a winding speed of 80 m/min (overfeed 150%). At this time, a contact type heater is used and the length is 300 mm. Also, the heater temperature is 115 for the yarn.
℃, while the contact pressure between the package and the winding drum was 200 g. The CR value of the yarn before dyeing is 44%. (Comparative Example 1) Same as Example 1, nylon 66 was overfed 15
%, without heater, wound with contact pressure of 200g,
This is the case of the conventional example. (Comparative Example 2) The overfeed was 250%, the yarn temperature was 160°, and the other conditions were the same as in Example 1, but outside the scope of the present invention. (Comparative Example 3) The overfeed was 30% and the other conditions were the same as in Example 1, but outside the scope of the present invention. (Comparative Example 4) The yarn temperature was 215°C and the other conditions were the same as in Example 1, but outside the scope of the present invention. These results are shown in Table 1.

[Table] As is clear from the above table, very good results can be obtained in the case of the invention, but in cases other than the invention, some disadvantages occur and are not preferable. (Example 2) A stretchable bulky yarn processed with nylon 6 70d/24f at a heat-set yarn temperature of 178°C in the false twisting process was used as the supplied yarn, and the yarn temperature was raised to 105°C.
Other conditions are the same as in Example 1. Comparative Examples 1 to 3 have the same conditions as Comparative Examples 1 to 3 of the first example, but Comparative Example 4 has a yarn temperature of 185° C. and is otherwise the same as Example 2. The CR value of the yarn before dyeing is 41%.

[Table] As is clear from the above table, the same effects as in Example 1 were obtained, and the area of the present invention was the best. As described above, the present invention actively overfeeds the stretchable bulky yarn of polyamide by 50 to 200% using a knit roller and heats it to a certain temperature range under no tension, thereby eliminating the latent crimp of the bulky yarn. The material is developed, heat-shrinked, and then wound up using a surface friction-driven winding device with a low contact pressure, so compared to conventional methods, the CR value after dyeing is almost the same as before dyeing. Since a soft package is obtained, the skein removal step can be omitted and cheese dyeing can be directly performed.

[Brief explanation of the drawing]

FIG. 1 is a graph showing the relationship between overfeed rate and yarn temperature in the present invention, and FIG. 2 is an explanatory diagram showing an example of an apparatus for carrying out the method of the present invention.
FIG. 3 is an explanatory diagram showing another example of an apparatus for carrying out the method of the present invention. 1... Supply package, 3... Nitz roller, 5...
Heater, 8... winding device.

Claims (1)

[Scope of Claims] 1. When a polyamide elastic bulky yarn is pulled out from a yarn supply package using a nip roller and is wound into a cheese-like package using a surface friction drive type winding device while overfeeding the yarn at a speed faster than the winding speed, The overfeed is 50~200
At the same time, the yarn temperature is raised to a range that satisfies the following formula using a heater installed between the nip roller and the winding device, causing thermal contraction in the yarn to avoid a sagging state and create a tension-free state. A method for winding a cheese dyeing package of polyamide stretchable bulky yarn, characterized in that the package is wound up into a cheese-like package at the bottom. T＞t＞(0.4F+40)℃ However, T: Heat-set yarn temperature during bulk processing of supplied bulky yarn (℃) t: Yarn temperature (℃) F: Overfeed rate (%)