JPS6136106B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bulky spun yarn having a multilayer structure and a method for producing the same. Conventionally, bulky spun yarns have often been obtained by a method of mixing two types of short fibers with different heat shrinkage rates to form a yarn and then heat-treating the yarn. The bulky spun yarn produced by this method has a tendency for highly shrinkage fibers to converge in the center of the yarn, so the texture of the woven or knitted fabric obtained by knitting this spun yarn has a so-called cored texture. This resulted in a disadvantage of lack of flexibility. When thin fibers are used to compensate for this drawback, there is a problem in that the woven or knitted fabric lacks tension and stiffness, that is, repulsion. Furthermore, as a result of the high shrinkage fibers converging in the center of the yarn, the low shrinkage fibers come out further to the outside, but in this case, the low shrinkage fibers are disarranged in random directions, resulting in a rough texture. I also had one. The object of the present invention is to improve the above-mentioned drawbacks and to obtain a cashmere-like spun yarn that has a soft touch surface, is coreless, and can provide a woven or knitted fabric with appropriate tension and stiffness. That is, the present invention provides a spun yarn consisting of at least three or more types of short fibers, in which the short fibers with a fineness of 1 to 3 denier are relatively located in the core and constitute the innermost part, and the short fibers with a fineness of 2 to 3 denier Short fibers of 10 denier are located around the innermost fibers to form the middle part, and ultrafine short fibers with a fineness of 1 denier or less are located around the middle part fibers to form the outermost part. In order to obtain such a bulky spun yarn, the roving consisting of short fibers with a fineness of 1 to 3 denier is mixed with ultrafine staple fibers with a fineness of 1 denier or less in the roving process. A mixed sliver consisting of short fibers having a higher heat shrinkage rate than the ultrafine short fibers and a fineness of 2 to 10 denier is supplied in a superimposed manner and twisted to form the roving. The present invention provides a method for producing a bulky spun yarn having a multilayer structure, in which short fibers of a mixed sliver are coated to form a two-layered roving, the two-layered roving is spun, and then heat treated. The present invention will be explained in detail below. The spun yarn according to the present invention is a bulky spun yarn in which the short fibers in the outermost part, the short fibers in the middle part, and the short fibers in the innermost part form a concentric multilayer structure. If the fiber arrangement in the cross section of this bulky spun yarn is schematically shown, it is as shown in Figure 1 (B). C indicates ultrafine short fibers with a fineness of 1 denier or less. FIG. 1 is a diagram showing a cross section of a spun yarn before and after heat treatment, with FIG. 1A showing the cross section before the treatment, and FIG. 1B the cross section after the treatment. The short fibers used to obtain the spun yarn of the present invention are not particularly limited as long as they are short fibers for spinning, but since ultrafine fibers and high heat shrinkage fibers are required, artificial fibers are preferable. The explanation will be given below. First, the short fibers constituting the innermost part may be natural fibers, artificial fibers, or a mixture of these fibers, and there are no restrictions on the cross-sectional shape, fiber length, etc. of the fibers. The fibers need to be in the 1-3 denier range. That is, the fineness is 1 to 3.
With a spun yarn exceeding the denier, it is impossible to obtain a woven or knitted fabric with a coreless texture, and in order to obtain a woven or knitted fabric with a coreless texture, which is the object of the present invention, it is necessary to It is desirable that the short fibers constituting the outer layer have excellent crimp performance, but in particular, the fineness needs to be at least 1 denier; if it is less than that, it will be difficult to obtain a woven or knitted fabric with sufficient resilience. . or,
The blending ratio of short fibers that make up the innermost part is 10% to 40%.
It is desirable that it be within the range of . This is because if the blending rate exceeds 40%, it becomes difficult to make a two-layered yarn in advance. Next, the short fibers constituting the middle part need to have a fineness in the range of 2 to 10 deniers. That is,
By using relatively thick fibers with a fineness of 2 denier or more, the tension and elasticity (resilience) required for woven and knitted fabrics are achieved.
It gives. Furthermore, in order to impart efficient repellency to woven or knitted fabrics, it is desirable to use man-made fibers such as irregular cross-section fibers, hollow fibers, or a mixture thereof, and in particular, use hollow fibers with a hollow content of 5 to 40%. This is desirable. However, the fineness of the short fibers should be 10 denier or less, and if the fineness exceeds 10 denier, the woven or knitted fabric will have a rough and hard texture. It is desirable that the blending ratio of the short fibers constituting the middle section be in the range of 25 to 55%. When the blending ratio is less than 25%, it is difficult to impart the necessary tension and firmness to the woven or knitted fabric, and on the other hand, when the blending ratio exceeds 50%, the texture becomes rough and hard, which is not preferable. Furthermore, the short fibers constituting the outermost part must be ultrafine fibers with a fineness of 1 denier or less; if the fineness exceeds 1 denier, a spun yarn that can provide a woven or knitted fabric with a soft touch surface is obtained. This is because it becomes difficult. The spun yarn of the present invention has the above-described short fibers arranged concentrically to form a bulky yarn with a multilayer structure. For example, a yarn with such a structure can be produced as follows. It will be done. That is, a roving made of short fibers with a fineness of 1 to 3 denier is made in advance, and in the roving process, the roving is mixed with ultrafine short fibers with a fineness of 1 denier or less and having a higher heat shrinkage rate than the ultrafine short fibers. and short fibers with a fineness of 2 to 10 deniers, and are supplied in a layered manner and twisted to form the roving.
A two-layered roving is made by covering short fibers of ~3 denier with the short fibers of the mixed sliver. After spinning this two-layer structure roving, it is heat-treated to obtain a multi-layer structure bulky spun yarn. In this case, ultrafine short fibers with a fineness of 1 denier or less can be obtained by the usual spinning and drawing method, but in particular, in order to obtain ultrafine fibers, two components with a sea-island cross section are used, as is already known. There are ultrafine fibers obtained by dissolving sea components, ultrafine fibers obtained by physically or chemically splitting the bonded parts of fibers with a cross section of a multi-component laminated structure, etc. Furthermore, short fibers with a fineness of 2 to 10 deniers form the middle part of the multilayered spun yarn described above, but they shrink during heat treatment after spinning, making them larger than the ultrafine short fibers. It is necessary to have a heat shrinkage rate, and desirably, the difference in heat shrinkage rate is 3% or more. The reason for this is that before heat treatment, the cross section of the two-layered roving or spun yarn looks like ultrafine short fibers C as shown in Figure 1A.
However, after heat treatment, the short fibers B with a fineness of 2 to 10 denier, which have a high heat shrinkage rate, shrink, resulting in the structure shown in Figure 1 B. This is because if the difference in heat shrinkage rate is less than 3%, it will be difficult to create a yarn with a structure in which the ultrafine fibers occupy the outermost portion. The present invention will be explained below with reference to the drawings. Figures 2 to 4 are embodiments showing the method for obtaining the spun yarn of the present invention, and Figure 2 shows the method for obtaining a two-layered roving before making it into a multilayered bulky spun yarn. This is a process diagram. In FIG. 2, the mixed sliver 2 taken out from the can 1 is a mixture of ultrafine short fibers with a fineness of 1 denier or less and short fibers with a fineness of 2 to 10 denier, and includes a guide 3, a bat crawler 4,
It is supplied to the aprons 6, 6' through 4' and drafted several times. On the other hand, the roving 12 made of short fibers with a fineness of 1 to 3 deniers is similarly supplied to the aprons 6, 6' via the guides 13, 14, and is supplied to overlap the mixed sliver 2, and is fed to the front rollers 7, 7'.
After that, it becomes a two-layered roving 8 and a flyer 9.
The fibers are twisted and wound around the roving woodwind 10. still,
5 and 5' are middle rollers, and 11 is a spindle. FIG. 3 shows an enlarged perspective view of the mixing part in the process diagram of FIG. A twist of 0.4 to 0.7 times/25.4 mm is applied, and the width is usually 5 mm or less. This roving 12 is overlapped near the center of the mixed sliver 2, drafted, and the front roller 7,
If twist is applied immediately after exiting 7', mixed sliver 2
covers the roving 12 so as to wrap it around, resulting in a roving having a two-layer structure. Furthermore, FIG. 4 is an enlarged perspective view showing another example of the method for obtaining the spun yarn of the present invention, which is an effective means for changing the blending ratio of short fibers in the innermost portion. That is, the roving 12 is supplied to the front rollers 7, 7' from the supply rollers 15, 15'. At this time, the draft magnification between the supply rollers 15, 15' and the front rollers 7, 7' is
The draft magnification between the aprons 6, 6' and the front rollers 7, 7' can be made different, so that
The blending ratio of short fibers in the innermost portion can be changed very easily. In the spun yarn of the present invention, a two-layered roving is made in this way, and after spinning this roving, heat treatment is performed.
Short fibers with a fineness of 2 to 10 denier with a high shrinkage rate are shrunk, and the short fibers with a fineness of 1 to 3 denier are in the innermost part, and the short fibers with a fineness of 2 to 10 denier with a high shrinkage rate are in the middle. Because it is a bulky spun yarn with a multilayer structure in which ultra-fine short fibers with a fineness of 1 denier or less are present in the outermost part of the shell, this spun yarn has a soft touch surface, and has no core and a moderate texture. It is possible to add tension and stiffness to woven or knitted fabrics. That is, since the outermost part is composed of ultrafine short fibers with a fineness of 1 denier or less, it can have a soft surface, and the difference in heat shrinkage is used to obtain a bulky spun yarn. According to the paper, during heat treatment, the parallelism of the low-shrinkage short fibers is disturbed during the process in which high-shrinkage short fibers move inside and low-shrinkage short fibers move outside, resulting in a rough texture. However, by using ultra-fine short fibers, it is possible to create a texture that is not rough even if the parallelism of the fibers is disturbed. Furthermore, since the spun yarn of the present invention is a bulky spun yarn with a multilayer structure as shown in FIG. 1B, it can have a coreless texture. In other words, short fibers constituting a spun yarn generally vary in position during the process of manufacturing the spun yarn, that is, when they are drafted and twisted. In other parts, one short fiber moves to the outer layer of the yarn, so its position is not constant. Therefore, in conventional bulky yarns, which were obtained by simply blending high-shrinkage fibers and low-shrinkage fibers and heat-treating them, layer separation can be achieved by heat-treating the yarn to shrink the high-shrinkage fibers and migrate the fibers. Therefore, efficient layer separation is not possible with a bulky yarn having a multilayer structure such as that of the present invention, and the fiber arrangement is greatly disturbed. On the other hand, in the spun yarn of the present invention, between the short fibers A forming the innermost part and the short fibers B and C forming the middle part and the outermost part, two
Since a layered structure is formed, migration of short fibers is difficult to occur between these short fibers, and migration mainly occurs between short fibers B forming the middle part and short fibers C forming the outermost part. The layer separation is carried out efficiently and the fiber arrangement is hardly disturbed. Therefore, in the multilayer bulky spun yarn of the present invention, the short fibers B, which constitute the middle part made of relatively thick denier fibers, are wound around the short fibers A, which constitute the innermost part. Short fibers C constitute the outermost part. It has a new structure. Therefore, when a woven or knitted fabric is made using the bulky spun yarn of the present invention, the short fibers A in the innermost part not only serve as a cushion, but also the short fibers B in the middle part. is wound in a spiral around the short fibers A in the innermost part, so it works to reduce the pressure (contact pressure) between the yarns in woven and knitted fabrics, creating a woven fabric with a coreless texture. A knitted fabric can be obtained. The heat treatment is preferably carried out at a dry heat temperature of 130°C to 200°C or a moist heat temperature of 80°C to 130°C. You can go after that. Examples will be described below. The fibers constituting the innermost, middle, and outermost sections have finenesses of 2 denier, 4 denier, and 0.8 denier, respectively, and the boiling water shrinkage difference between the fibers forming the middle section and the outermost section is Using 6% polyester short fibers, the rovings made in advance with short fibers with a fineness of 2 denier are overlaid on a mixed sliver consisting of short fibers with a fineness of 4 denier and 0.8 denier, and then fed to the roving machine and twisted. The yarn obtained by spinning this two-layered roving is processed into a yarn with a cotton count of ^30/25 , and the style of the fabric woven with this yarn is improved. The results of evaluating the crimp elasticity are shown in Experiment No. 1, and furthermore, when a fiber with a crimp modulus of 85% is used as the fiber constituting the innermost part (the normal crimp modulus is 50 to 70%). %) is shown in Experiment No. 2, and Experiment No. 3 shows an example in which the fibers constituting the outermost part are short fibers with a fineness of 0.5 denier and a boiling water shrinkage rate of almost zero.
I was able to obtain it by The results are shown in Table 1. As a comparative example, using the same short fibers as in Experiment No. 1, a spun yarn obtained by the conventional blending method (random blending) was used in Experiment No. 4. Experiment No. 5 is an example in which the fiber fineness is 4 denier and the spun yarn obtained by the same method as Experiment No. 1 is used.
Furthermore, Experiment No. 6 shows an example in which the fineness of the short fibers constituting the middle part is 1 denier and the spun yarn obtained by the same method as Experiment No. 1 is used, and Experiment No. The fineness of the short fibers that make up the outer shell is 3.
In addition, in Experiment No. 8, an example in which the difference in boiling water shrinkage rate between the short fibers constituting the outermost part and the short fibers constituting the middle part is 0 is shown in Table 1. It was shown in In Experiment No. 9, an example in which the short fibers constituting the middle part were hollow fibers with a hollow ratio of 10% is shown in Table 1 as an example. 【table】

[Brief explanation of the drawing]

FIGS. 1A and 1B are cross-sectional views showing cross sections of the multilayer bulky spun yarn of the present invention before and after heat treatment, and FIG. A process diagram for making a layered roving is shown, and FIGS. 3 and 4 are enlarged perspective views of the mixing part in the process diagram of FIG. 2. A...Short fibers forming the innermost part, B...Short fibers forming the middle part, C...Short fibers forming the outermost part, 2...Mixed sliver, 8...Two-layer structure roving, 12... roving.

Claims (1)

[Scope of Claims] 1 A spun yarn consisting of at least three types of short fibers, wherein the short fibers with a fineness of 1 to 3 denier are relatively located in the core and constitute the innermost part, and the fineness is 2 to 3 denier. ~
Short fibers of 10 denier are located around the innermost fibers to form the middle part, and ultrafine fibers having a fineness of 1 denier or less are located around the middle part fibers to form the outermost part. A multi-layered bulky spun yarn characterized by: 2. The spun yarn according to claim 1, wherein the short fibers having a fineness of 2 to 10 deniers constituting the middle part are hollow fibers having a hollowness ratio of 5 to 40%. 3. In the roving process, roving consisting of short fibers with a fineness of 1 to 3 denier is mixed with ultrafine short fibers having a fineness of 1 denier or less and short fibers having a higher heat shrinkage rate than the ultrafine staple fibers and having a fineness of 2 to 10 denier. The short fibers of the mixed sliver are supplied so as to be overlapped and twisted to form the roving, and the short fibers of the mixed sliver are coated around the short fibers to form the roving, which has a two-layer structure. 1. A method for producing a multilayer bulky spun yarn, which comprises spinning a roving and then heat-treating it to form a multilayer structure of an innermost, middle, and outermost part. 4. Claim No. 4, wherein the mixed sliver consists of ultrafine short fibers with a fineness of 1 denier or less and short fibers with a boiling water shrinkage rate that is 3% or more greater than the boiling water shrinkage rate of the ultrafine short fibers and a fineness of 2 to 10 denier. The method described in Section 3.