JPS61194236A - Processed yarn having fine crimps and its production - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a processed yarn having fine crimps and a method for producing the same.

More specifically, it relates to a processed yarn with extremely fine crimps, which could not be achieved in the past, and its manufacturing method, while using a general false twist crimping technique as a processing method for thermoplastic multifilament yarn. It is.

According to the present invention, a multifilament processed yarn made of single fibers having an appearance similar to the twist of cotton, and a method for producing the same are realized.゛(Prior art) It has been a long-standing dream to impart fine crimps to synthetic fibers, but this has not yet been realized.

On the other hand, among the various crimping techniques currently available, the false twisting method is the one that can provide the finest crimps.

However, in this method, each single fiber is false twisted as a multifilament yarn, so the false twist coefficient (the product of the number of false twists and the square root of the yarn denier) is generally extremely high. Even if processing conditions of about 30,000 are adopted, the twist coefficient of each single fiber is generally only about 5,000. However, in an attempt to reduce the number of constituent fibers and increase the number of false twists, in order to obtain a crimp equivalent to the number of twists that cotton has,
Even if we try to give a twist of 5,000 to 8,000 T/m per unit, in reality, the single fibers will not be able to withstand the processing tension and will break or become completely uneconomical, making it unfeasible for industrial implementation. There is a lack of

On the other hand, Japanese Patent Application Laid-Open No. 58-70725 proposes pressing a single fiber with a hard processing roller and applying a large number of impressions to the side surface of the fiber to produce minute changes on the fiber surface. There is. However, in such proposals, the main focus is on applying deformation in a state where the crystal structure has not progressed much or in a heated state in order to make it easier to deform the single fiber by pressing, and it is difficult to fix the deformation. Little consideration has been given to whether For this reason, the yarn obtained by this proposal generally has a high residual shrinkage rate, and the fine effect imparted to it is reduced by ironing or heat treatment in a post-process. Furthermore, since the pressing action is a planar action by rollers, it has little effect on the wood quality when it comes to crimp, which is deformation accompanied by twisting.

(Problems to be Solved by the Invention) In view of the above-mentioned problems, an object of the present invention is to provide a synthetic fiber multifilament yarn having extremely fine single fiber crimps and a method for producing the same. The purpose of the present invention is to provide a novel processed yarn that can exhibit an appearance similar to the fine twists of cotton and a texture effect based on the appearance.

(Means for solving the problems) The processed yarn having fine crimps of the present invention has the following configuration.

That is, it is a processed yarn made of multifilament yarn, and each single fiber constituting the multifilament yarn has a plurality of indentation surfaces running diagonally with respect to the fiber axis direction on its side surface, and the single fiber braid length is This is a processed yarn having fine crimps, which is characterized by substantially having an average of 5 or more intersections between the indentation surfaces within 1 mm.

Further, the method for producing processed yarn having fine crimps of the present invention includes:
It consists of the following composition.

That is, after a thermoplastic multifilament yarn is false-twisted and crimped, the yarn is relaxed to develop false-twisted crimps, the phase of each single fiber crimp is shifted, and then the yarn is false-twisted and crimped again. This is a method for producing processed yarn having fine crimps, which is characterized by performing a shrinking process.

(effect) Hereinafter, the present invention will be roughly explained in detail.

In the processed yarn of the present invention, running diagonally with respect to the fiber axis,
The multiple indentation surfaces on the sides of a single fiber are essentially planar traces caused by the crimping of single fibers that occur when the single fibers are tightly focused by heating in a heater during false twisting and crimp processing. It is. This is a change in the shape of the side surface of a single fiber that generally occurs during false-twisting and crimp processing, and particularly when a semi-drawn yarn is simultaneously drawn and false-twisted, it exhibits a very large planar shape. When viewed from the perspective of the cross section of a single fiber, such a plane generally forms one side of a pentagon to hexagon, and extends almost continuously in the fiber axis direction.

Generally, when a yarn that has been subjected to false twisting and crimp processing is in a relaxed state, the single fibers will exhibit twisting due to the deformation and torque produced by the heat setting and untwisting of the false twisting. The indentation plane on the side surface also appears to cover the single fiber surface in a spiral manner in the direction of the fiber axis.

When this material is subjected to moist heat, hot water treatment, etc. in a subsequent process, it becomes apparent as a large deformation as crimping.

At this time, the finer the pitch of the planes exhibiting the spiral shape, the smaller the pitch of the crimp becomes possible, but as described in the prior art described above, this is difficult.

For reference, FIG. 2 shows a microscopic photograph of the side surface of a single fiber of a conventional false twisted yarn. FIG. 2 is a microscopic photograph of a normal woolly yarn that has been subjected to only the first false twisting process in Example 1, which will be described later.

Therefore, the present invention focuses on dividing the indentation plane on the side surface into small pieces by the square indentation plane, and making crimp-like minute deformation evident on each small divided plane.

Therefore, the processed yarn of the present invention substantially has an intersection of indentation surfaces of 5 gA or more on average during a single fiber braid length of 1 mm.

That is, FIG. 1 is a microscopic photograph of the single fibers constituting the finely crimped processed yarn of the present invention, and is a microscopic photograph of the yarn of the present invention 1q processed in Example 1 described later.

As can be clearly seen by comparing FIG. 1 with FIG. 2, the yarn of the present invention has a large number of intersections of impression surfaces.

According to the various findings of the present inventors, if the indentation planes on the side surface intersect less frequently, even if there are intersecting points, the difference in appearance from ordinary false-twisted crimped yarn is unlikely to appear. For example, if there are an average of 5 or more intersections between the indented surfaces per 1 mm of single fiber braid length, the overall appearance can exhibit a fine crimp shape.

On the other hand, even when the indentation surface is very finely divided, the appearance of fine crimp tends to weaken. The occurrence of shrinkage tends to become unrecognizable, and in that case, it tends to be difficult to distinguish it from straight single fibers. Regarding this point, according to the findings of the present inventors, in terms of the size of the indentation surface, it is preferable that there is a portion having a length of about 1/2 or more of the outer circumference of each car llft, and the fineness is 2d. ,3d
In the case of single fibers of about
The number is preferably within 0 to 50 pieces. □On the other hand, even if single fibers have minute crimps, if the large deformation as a multifilament yarn is extremely strong, the appearance on the fabric will be dominated by the disorder of the large deformation, and the fine crimps will tends to be less noticeable.

In order to avoid this, it is important to keep the crimp rate of the yarn as low as possible, and the yarn of the present invention exhibits the most noticeable surface effect due to fine crimp in yarns with low crimp development of 2% or more and 100% or less. can be demonstrated.

The processed yarn of the present invention includes thermoplastic multifilament yarn,
After applying the false twist crimp processing, the yarn is relaxed to develop false twist crimp, and the phase of each single m fiber crimp is shifted,
After that, it can be manufactured by performing false twisting and crimp processing again.

What is important in obtaining the processed yarn of the present invention is that the multifilament yarn, which has been subjected to false twist and crimp processing, is once relaxed, and the crimp of the single fibers is developed, and the phase of each single fiber crimp is Shun, who has shifted the thread, is going to undergo the false twisting process again. When false twisting is performed again without shifting the crimp phase, the number of intersections of the indentation surfaces formed on the side faces of the fibers is small, and the crimp can be divided into many parts within a range of 1 mm or less. As a result, even if the torque can be reduced, fine crimp cannot be developed, and it is difficult to obtain the processed yarn of the present invention. The degree of relaxation cannot be unambiguously determined, but according to the findings of the present inventors, it is generally best to relax the body to a state under tension of 0.05 g/D or less. And this is a rough guideline. Here, in order to shift the crimp phase by relaxing, it is effective to provide a relaxation region in the middle of the successive false twisting processes as shown in FIG.

That is, FIG. 3 is a schematic diagram showing an example of the processing process for obtaining the processed yarn of the present invention, and in the same figure,
1 is a supply system, 2, 3.4, 5.6 are yarn feeding rollers, 7 is a winding section, 8.9.10 is a heat fixing heater, 11.1
2 is a false twisting heating device. 1 between thread feed rollers 2 and 3
This is the second false twisting area, and the area between the yarn feed rollers 3 and 4 is a relaxing area, and the phase of single fiber crimp is shifted in this relaxing area. The area between yarn feed rollers 4 and 5 is a second false twisting area, and the area between yarn feed rollers 5 and 6 is a relaxation heat treatment area for normal heat setting.

When carrying out the method of the present invention, if there are restrictions on the equipment, the false-twisted yarn that has undergone the first false twist is wound once, and then untwisted in a natural state again. It may also be subjected to a second false twist and crimp process. In addition, the method of the present invention is applicable not only to the case of only two false twisting processes, but also to
The false twisting process may be performed more times than that.

Furthermore, although it is possible to obtain the yarn of the present invention by performing relaxing heat treatment using a second heater in each false twisting process, in order to shift the crimp phase, the first false twisting process requires It is preferable not to apply relaxing heat treatment.

In producing the processed yarn of the present invention, the larger the number of false twists, the finer the crimp, but according to the knowledge of the present inventors, if the twist coefficient is 20,000 or more, multiple false twists are required. By processing, a yarn of the above-described configuration of the invention is obtained.

In addition, what is important when implementing the method of the present invention is that
Processing is carried out under processing tension and false twisting temperatures that ensure compression deformation and heat fixation of the fibers. Tokoro WP
A false-twisting temperature of approximately -100° C. or higher than the melting point of the material is required, except when deforming a semi-drawn yarn called OY by false-twisting at the same time as drawing.

In the case of simultaneous drawing and false twisting of semi-drawn yarn, the first temporary MFM
Pressure deformation is possible if the temperature is above the glass transition point, but from the second time onwards, the melting point temperature -100
It is desirable to heat set at a tentative M temperature of about 0.degree. C. or higher.

Further, the direction of false twisting is not particularly limited, and the first false twisting direction and the subsequent false twisting directions may be the same direction or different directions. Furthermore, two or more multifilament yarns that have already been false-twisted may be simultaneously supplied for the next false-twisting process. Generally speaking, there is no particular limit to the number of times of false twisting after the second time, and it may be any number of times, but as mentioned above, if there is too much side deformation, the effect will be diminished in terms of crimp. There are some, so you need to be careful.

It goes without saying that the yarn according to the present invention also includes the following.

In other words, fibers made by intertwining the yarns of the present invention, fibers subjected to high-order processing such as heated fibers, fibers to which other substances such as glue or resin are attached, fibers with various finenesses, various shrinkage rates, various dyeability, or composite fibers. Those that are composed of, those that have changed fibers, those that exist in fabrics such as woven or knitted fabrics, those that are twisted, interwoven, or cross-knitted with other threads, those that exist in other structures, and spools. Or something that exists in a recognized isothelial state.

In addition, in the above explanation, crimp development rate refers to processed yarn at 98°C.
Let it shrink freely for 20 minutes in clean water, and after drying,
Measure the length under a load of mQ/d and let this length be A,
The length under a 0.1 o/d load is measured and this length is designated as B, which is a value expressed as ((B-A>/B) x 100 (%)).

In addition, the feed rate in the examples described later refers to the surface speed of the roller on the yarn supply side in each action area, and the surface speed of the feed roller or take-up roller in each action area, taking Fig. 3 as an example. When v□, ((V, -v,)/VD)X1
It is a value expressed in 00 (%).

(Example) Example] A polyethylene terephthalate yarn having a birefringence Δn of 30×10 −3 was drawn and simultaneously false-twisted under the following conditions and wound up.

Processing speed: 450 m/min Supply speed: 250 m/min False twisting device: Friction type circumscribed false twisting device False twisting direction: Z direction Heater temperature = 210°C Winding feed rate: +7% The obtained processed yarn is 75D-36f It is a woolly processed yarn.

While unraveling the yarn from the cheese, it was again subjected to false twisting under the following conditions.

During such unraveling, the woolly processed yarn is naturally relaxed, crimps develop, and the phases of the crimps of each single fiber are shifted.

The tension state during this relaxation is 2Q (0,03CI/D)
It is.

Processing speed: 150 m/min Supply speed: 145.5 m/min False twisting device: Pin false twisting device Pin rotation speed: 450. OOOrpm (Z direction) Temporary M temperature: 210°C Relaxation heat setting treatment feed rate: +18% Relaxation heat setting treatment temperature = 180°C A side micrograph of the obtained processed yarn is shown in Fig. 1. As can be seen from the figure, a large number of intersecting indentation surfaces can be seen on the side surface of the single fiber. The average number of intersections of the indented surfaces was 40 between 11 II m of single fibers. For comparison, FIG. 2 shows a side micrograph of a single fiber subjected to only the first false twist. Both images are magnified 450 times, and it can be seen that the yarn of the present invention has remarkable fine crimp. Furthermore, the crimp occurrence rate of the yarn of the present invention was 21%.

Furthermore, using the yarn of the present invention obtained by performing the above two false twisting processes, the fabric was woven at a density of 101 yarns/inch in the vertical direction and 95 yarns/inch in the horizontal direction, and the woven fabric was subjected to a relaxing treatment using hot water. did. The fabric thus obtained was extremely flexible and had a fuller feel compared to raw silk tuck. In addition, the feeling of bulkiness that is often seen in textured yarn fabrics hardly appeared, which was favorable.

Example 2 A yarn of the present invention was produced using a drawn polyamide yarn of 70D-24f according to the process outlined in FIG. The main processing conditions are as follows. The crimp rate of this yarn was about 40%, and the average number of crimp crossings between 111 g of single fibers was 30.

(1) First false twisting area processing speed: 100m/min Supply feed rate knee 2% Number of false twists: 3000T/m (S direction) False twisting temperature = 17
5℃ (2) Relaxation zone feed rate: +12% Tension state during relaxation: 0.015g/D or less (3) Second false twisting zone processing speed: 102m/min Number of false twists: 2700T/m (Z direction) False twisting temperature: 18
After knitting the yarn thus obtained at 5° C., it was dyed. When the surface of the knitted fabric thus obtained was observed, it was found that the fabric had beautiful stitches with very well-oriented knitting, which could not be obtained with conventional woolly textured yarns or modified false twisted yarns.

Comparative Example In Example 2, a processed yarn obtained when no intermediate relaxation area was provided was studied.

In this case, it was difficult to stably process the yarn at the same processing speed as in Example 2, so the false twisting device was changed to an air false twisting method. The false twisting temperature and direction were the same as in Example 2, and the air false twisting was performed at the same pressure of 5 kl/ant both in the first and second times. The number of false twists on each false twist heater is 2950 T/m and 2600 T/m. The side surface of the single fiber of the processed yarn thus obtained was enlarged and the number of intersections of the indentation surface was investigated, and the number of intersections was found to be 1a+gm of single fibers.
The average was 1.2 pieces per hit. Using the thus obtained yarn, jersey knitting was carried out in the same manner as in Example 2, and a rough dyeing process was carried out.Although the knitted fabric bias was not that of ordinary woolly yarn, the disturbance of the knitting direction was It was not much different from the woolly yarn, but was clearly inferior to the product of the present invention in Example 2.

(Effects of the Invention) As described above, the greatest feature of the yarn of the present invention is its fine crimp form.

As a result, for example, when the yarn of the present invention is woven as taffeta, it is clearly different from the paper-like texture that occurs when using raw silk, and moreover, it has a moderate texture without the fluffy feeling that conventional crimped yarns have. A fabric with good bulge is obtained.

Furthermore, when the yarn of the present invention is used as a highly twisted yarn, fine deformation occurs in the outermost layer fibers, resulting in a slightly warm strongly twisted yarn fabric that is different from conventional raw silk highly twisted yarns.

On the other hand, when the yarn of the present invention is used in a knitted fabric, the crimp pitch is finer than the stitches, so it is possible to eliminate the disorder of the stitches that cannot be avoided with conventional false-twisted crimped yarns. A fabric with a very fine knitting direction can be obtained.

In general, the effect of fine crimping is extremely effective in improving the number of interlaces and the interlace strength of interlaced yarns subjected to fluid treatment or the like. This is presumed to be a catching effect due to side deformation.

Furthermore, when the yarn of the present invention is used as a filament side in a single fiber, especially a composite yarn with cotton, the effect is great.

Whether it is a core-sheath structure or a mixed fiber structure, the composite state with single fibers not only improves entanglement due to the same snagging as mentioned in the previous section, but also due to the finer crimp form. , the discomfort caused by the crimp form with cotton has been eliminated, and the crimp rate is lower than that of ordinary false-twisted crimped yarns, and the shrinkage rate after multiple false-twisting is low. As a result of the reduction in the shrinkage behavior, the discomfort caused by the difference in shrinkage behavior does not appear as a substantial problem, and it is possible to obtain a composite yarn with excellent morphology.

[Brief Description of the Drawings] Figure 1 is a microscopic photograph showing one of the configuration examples of the processing system having fine crimps of the present invention, and is a microscopic photograph of the yarn of the present invention obtained in Example 1. be. FIG. 2 is a microscopic photograph showing an example of the morphology of a single fiber side of a normal false-twisted yarn, and is a microscopic photograph of a conventional woolly yarn that has undergone only the first false-twisting process during the processing process of Example 1. be. FIG. 3 is a schematic diagram showing an example of the processing process for obtaining the processed yarn of the present invention. Brief description of the drawings 1: Supply system 2.3, 4, 5.6: Yarn feed roller 7: Winding section 8.9.10: Heat fixing heater 11.12: False twist heating device

Claims (4)

[Claims] (1) A processed yarn consisting of a multifilament yarn, in which each single fiber constituting the multifilament yarn has a plurality of indentation surfaces running diagonally with respect to the fiber axis direction on its side surface, and the single fiber A textured yarn having fine crimps, characterized in that the indented surfaces substantially have an average of 5 or more intersections with each other within a length of 1 mm. (2) The processed yarn having fine crimps according to claim (1), which is a low crimp yarn with a crimp development rate of 2% or more and 100% or less. (3) After false twisting and crimp processing is applied to the thermoplastic multifilament yarn, the yarn is relaxed to develop false twisting and crimp, and the phase of each single fiber crimp is shifted, and then false twisting is performed again. A method for producing processed yarn having fine crimps, the method comprising performing a crimping process. (4) A method for producing a processed yarn having fine crimps as set forth in claim (3), characterized in that upon relaxation, the yarn is relaxed to a state under a tension of 0.05 g/D or less.