JPS633997B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for producing a highly drapeable fabric. (Prior Art) Hitherto, fabrics aiming for a silky feel have been required to have high drape properties as one of the fabric properties. Polyester fabrics have been subjected to alkali weight loss treatment as one of the means to obtain high drapability. This alkali weight loss treatment is performed for the purpose of reducing the interfiber pressure (contact pressure) generated at the intersection of the warp and weft. Generally, in a flat weave, the warp and weft alternately float and sink, resulting in a large number of intersecting points, and the contact pressure mentioned above does not decrease easily, which increases the alkali weight loss rate. I had to fake it. If the alkali weight loss rate is increased, the threads constituting the fabric will become "thinner" and the degree of bending of the threads in the fabric will be reduced, making it impossible to obtain a fabric with high drape. The "thinness" of the yarns that make up such textiles
In order to cover this, it is best to use a fabric with a high warp density, but there is a limit to how high the warp density can be made with normal plain weave fabrics, especially when using high-speed rotation water jets that are widely used today. This is a problem in loom fabrics because this limit value is at a lower level than in ordinary shuttle loom fabrics. This is a plain weave fabric, and as the density of the warp yarns increases, the number of heddle meters must be increased, and the number of heald frames must be increased. High-speed rotary weaving (normal shuttle looms have a rotation speed of about 150 revolutions/minute)
This is because warp yarns are strained and strained due to tension, which tends to cause warp fuzz or warp breakage. Table 1 shows the currently empirically known weaving limits of warp density in terms of warp cover factor CF _wp .
It will look like this. Here, the warp cover factor is CF _wp = √
Expressed as De x raw material density (lines/cm).

[Table] As shown in Table 1, the commonly used 50
With yarns of about denier (50 De), the warp density of gray looms is at most 320 threads/3.79 cm on ordinary looms, and 280 threads/3.79 cm on water jet looms.
At that time, the maximum warp cover factor CF _wp is 600 for an ordinary loom, and only about 530 for a water jet loom. For this reason, with conventional plain weave fabrics, there was a limit to the ability to obtain fabrics with high drape properties. (Object of the Invention) The object of the present invention is to improve the drawbacks of the conventional methods and to propose a method for producing a fabric having high warp density and high drapability. (Structure of the Invention) The present invention is a woven fabric using lightly twisted yarns of polyester filament for the warp yarns and hard twisted yarns of polyester filament for the weft yarns, in which a portion (tissue point) where the warp yarns are floating above the weft yarns, The parts sunk below the weft are arranged alternately for each weft, and
The warp yarns are woven with high density by a weaving method in which the weaving points of multiple adjacent warp yarns are paralleled to the same weft yarn,
The present invention provides a method for producing a highly drapeable fabric, which comprises subjecting the fabric to an alkali weight reduction treatment. In the method of the present invention, polyester filament yarns with a total fineness of 30 to 100 De, more preferably 50 to 75 De, are suitably used as warp yarns, and these yarns have a total fineness of 1000 T/
Yarns twisted at M or less (softly twisted yarns) are used. In addition, the weft is a polyester yarn similar to the warp, with a total fineness in the range of 50 to 300 de.
More preferably, yarns having a diameter in the range of 50 to 100 De are exemplified, and these yarns are subjected to strong twisting such that the twist coefficient α shown in the following formula (1) is α≧0.4. The weaving structure used in the method of the present invention consists of a part where the warp floats above the weft (in the present invention, such a part is referred to as a weave point) and a part sunk below the weft for each weft. It is necessary to arrange the warps alternately and to create a structure in which a plurality of adjacent warp yarns have the same weave point. FIG. 1 is a diagram showing an example of a woven structure used in the method of the present invention, in which FIG. FIG. As shown in Figure 1, the warp floats every weft thread (that is, weft thread 2 and weft thread 2') and sinks repeatedly, resulting in a tissue point (in the figure, the floating portion of the warp thread is indicated by an x mark, so (marks indicate tissue points). Furthermore, adjacent warps 1 and 1' have the same float,
By repeating the sinking process, the weaving points must be arranged in parallel to the same weft thread 2 or 2' for weaving. It is sufficient if multiple adjacent warp threads create tissue points for the same weft thread,
A preferred example of the plurality of warp threads is 2 to 4 warp threads, and FIG. 2 shows the organization chart thereof. By using such a structure, the contact friction between the warp threads is reduced to several times that of the conventional flat structure, which not only allows for high-speed rotation, but also greatly reduces the number of heald frames, making it possible to use a tapepet-based loom. It is possible to weave it, and it is possible to increase the warp density over a wide range. In order to obtain a fabric with high drapability, which is the object of the present invention, it is effective to have a large warp cover factor CF _wp , which is made possible by the large increase in warp density. be. The cover factor CF _wp of the fabric according to the method of the present invention is preferably in the range of 500 to 800. The fabric thus obtained can be subjected to alkali weight loss treatment to obtain a highly drapeable fabric. An effective alkali weight loss rate is 10 to 30%. (Action of the invention) Generally, woven fabrics are drawn while being subjected to tension in the warp direction during the finishing process, resulting in woven fabrics with a small degree of warp bending. Since a highly twisted yarn is used for the weft, a woven fabric with a warp structure (i.e., a structure in which the degree of curvature of the warp is greater than the degree of curvature of the weft) can be obtained. Fabrics with curved structures tend to exhibit superior drape properties. Furthermore, since the number of bends of the warp yarns in the woven structure is greater than the number of bends of the weft yarns, the warp structure becomes even more pronounced. Generally, if a lightly twisted yarn is used for the warp and a strongly twisted yarn with a one-sided torque is used for the weft, a willow fabric will be obtained. The fabric obtained by the method of the present invention may have a willow grain, but in order to prevent the occurrence of the willow grain, S-twist and Z-twist strongly twisted yarns are arranged alternately.
This can be obtained by a weaving method that cancels out the torque, and in short, it is necessary to weave the warp yarns at a high density. The weave structure used in the method of the present invention is extremely effective in increasing the warp density. Conventionally, in plain weave fabrics, the warp cover factor CF _wp could only be increased to 600 at most.
Especially when using a water jet room,
Due to the high speed rotation, the CF _wp could only be raised to a level below 550. With the tissue used in the method of the present invention, the cover factor CF _wp can be greatly increased as shown in Table 2.

[Table] In particular, when the cover factor CF _wp is 500 or more, a highly draped fabric can be obtained. In addition, in the method of the present invention, by using the above-mentioned weaving structure, the number of intersection points between the warp and weft is small.
Since the contact pressure can be lowered and lightly twisted yarns are used for the warp, the texture of the fabric does not become stiff and good drape properties are obtained. Furthermore, the alkali weight loss treatment lowers the contact pressure mentioned above and increases the inter-fiber voids, increasing flexibility and providing high drape. , the voids between the warp fibers are larger, making it suitable for obtaining a high drape. On the other hand, since the weft yarns are highly twisted yarns, there is less ``thinning'' caused by alkali weight loss treatment, which gives the fabric a sense of weight, makes it easier for the warp yarns to exhibit flexibility, and improves drapability. be. (Example 1) As the warp, a polyester filament yarn (75De, 48fil) with an irregular cross-sectional shape that was lightly twisted at 300T/M was used, and as the weft, a polyester filament yarn (75De, 72fil) with a 2500T/M twist was used.
Using strong twists applied to the S and Z twists, the S and Z twists are alternately driven into every two strands, and the first
The structure shown in Figure A was woven in a water jet loom. For comparison, a conventional plain weave was woven using the same yarn and the same warp density using a water jet loom. These fabrics obtained are
After going through the usual washing, relaxing and presetting processes, alkali weight loss treatment was performed and the texture was evaluated. Table 3 shows the results.

[Table] ◎...Very good, ○...Good, △...Slightly poor,
×...Poor The texture of the fabric according to the present invention had extremely high drapability and excellent texture compared to those of conventional textures. (Example 2) As the warp, a polyester filament yarn (50De, 30fil) having an irregular cross-sectional shape, in which the filaments constituting the yarn have shrinkage spots within the single yarn, was subjected to a gentle twist of 300T/M, and the weft was The polyester filament yarn used for the warp is 3000T/
A strong twist of M was applied to the S twist and the Z twist, respectively, and the S twist and the Z twist were driven alternately every two strands, and the fabric was woven in a water jet loom according to the structure shown in FIG. 1A. For comparison, a conventional plain weave was woven using the same yarn. The obtained fabric goes through a scouring, relaxing, and presetting process, and is then finished with an alkali weight loss treatment.
We evaluated the texture. Table 4 shows the results.

【table】

[Table] The fabric produced by the method of the present invention can be woven with a warp density that is higher than the limit warp density when conventional plain weave fabrics are woven in a water jet loom, and has unprecedented high drapability. A product with an excellent texture was obtained.

[Brief explanation of the drawing]

FIG. 1A is a tissue diagram showing an example of the woven structure used in the method of the present invention, FIG. 1B is a plan view schematically showing a fabric woven by the structure shown in FIG. FIG. 2 is a tissue diagram showing an example of another woven structure used in the method of the present invention. 1, 1'... warp, 2, 2'... weft.

Claims (1)

[Scope of Claims] 1. A woven fabric using lightly twisted polyester filament yarns for the warp yarns and hard twisted polyester filament yarns for the weft yarns, where the warp yarns float above the weft yarns (textile points) and the weft yarns The warp is woven with high density by a weaving method in which the downwardly sunken parts are arranged alternately for each weft, and the weave points of a plurality of adjacent warp threads are parallel to the same weft thread, and the fabric is A method for producing a highly drapeable fabric, characterized by subjecting it to alkali weight loss treatment. 2 Cover factor of warp threads in woven fabric (CF _wp )
The method according to claim 1, wherein the fabric is woven so that 500≦CF _wp ≦800.