JPS6055614B2 - Mixed fiber crimped yarn and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fiber for obtaining a fabric that has a bulky, fluffy feel, and is also stretchy and has no glare or luster.

In detail, it relates to a mixed crimped yarn consisting of two types of fibers with different single yarn fineness and cross-sectional shape, and its temperature. The present invention relates to a crimped yarn with mixed irregularity and fineness, characterized in that the thicker single yarn is comprised of fibers with irregular cross-sections having concave portions and pleated portions continuous in the longitudinal direction, and a method for producing the same. be. To produce mixed fiber yarns from thermoplastic synthetic fibers, there are two methods: mixing filaments before winding the undrawn yarn, and aligning different undrawn yarn bundles in the drawing stage and drawing them simultaneously. methods to make a mixed filament, and false twisting processing or drawing and simultaneous false twisting processing (hereinafter abbreviated as DTY processing) of different drawn yarns or undrawn yarns, or undrawn yarns mixed during spinning. In addition to the method,
There are various methods such as combining and twisting separately false twisted crimped yarns, but the mixed fiber crimped yarn of the present invention can be mixed or aligned at the stage of undrawn yarn or drawn yarn. It is obtained by applying false twisting processing or DTY processing to the twisted state. In general, undrawn yarns that are crimped yarns and have a difference in single yarn fineness of 3.5 deniers or more have a large elongation at break (hereinafter abbreviated as elongation) due to different cooling effects when wound at the same spinning speed. different.

When such an undrawn blended yarn is subjected to DTY processing, a difference in tension occurs during processing, and filaments with high elongation and large single filament fineness are entangled around a bundle of small filaments with low elongation to single filament fineness, and the core yarn This often results in unfavorable textured yarns with large loops protruding around them. The inventors of the present invention have conducted extensive research to solve these drawbacks. As a result, the present invention was achieved by discovering that it is effective to create a yarn with an irregular cross section that has concave portions and pleated portions that are continuous in the longitudinal direction of thick fibers.

The mixed fiber crimped yarn of the present invention is composed of two types of fibers with different finenesses, and the fibers with a larger fineness have an irregular cross-sectional shape with concave portions and pleats continuous in the longitudinal direction on the fiber surface. DTY refers to undrawn yarn or drawn yarn that is fiber.
It is obtained by processing or false twisting.

As shown in Fig. 3, an example of the cross-sectional shape of a fiber having concave portions and pleats that are continuous in the longitudinal direction on the fiber surface is a synthetic fiber with concave portions (concavities) and pleats on the fiber surface (
It has a cross-sectional shape with convex portions), and the depressed portions and pleated portions are continuous in the longitudinal direction of the fiber.

In the processed yarn obtained in this way, thick single yarns with irregular cross-sections are distributed with coarse crimps and spread around the outer periphery of the fiber bundle, and fiber bundles with fine fineness are in a bundled state. It has a slight crimp as it is, and exists in a meandering manner almost in the center of the mixed fiber bundle, as if threading between thick single threads.

When such fibers are woven, they have high tension and stiffness. When the number of pleats of the thick yarn with irregular cross section is within the range of 5 to 12, the knitted fabric becomes visually calm and deep without any glare or shine.

Fibers with such characteristics include fibers with a single filament fineness in the range of 5 to 15 denier, a drawn yarn bundle with an irregular cross section that has concave portions and pleated portions that are continuous in the longitudinal direction, and a single filament fineness within the range of 5 to 15 denier. It can also be obtained by simultaneously aligning a bundle of drawn yarns with a fineness of 1.5 denier or less and subjecting them to simultaneous false twisting.

However, such fibers of the present invention cannot be obtained by combining independently false-twisted coarse crimped yarns with irregular cross-sections and finely crimped yarns; The result is a knitted fabric with a texture and luster that is completely different from the knitted fabric made from the fibers of the invention. The essential requirements for producing the fibers of the present invention are to use two types of fibers having the above-mentioned fineness difference and cross-sectional shape, and to increase the number of false twists to 24,000/JD during false twisting.
(Here, D is the total denier of the mixed yarn after processing). This is because if the number of false twists is larger than the above range, the resistance when passing through the false twist spindle will increase and yarn breakage will occur frequently. Furthermore, the elongation of a fiber bundle with a smaller single filament fineness is not greater than the elongation of the other fiber bundle, and the mixing ratio of the fiber bundle with a smaller single filament fineness with the other fiber bundle is smaller than the latter. It is important to ensure that this does not happen.

In addition, when attempting to obtain a mixed fiber crimped yarn by DTY processing from the above two types of undrawn yarns, the drawing ratio DR is 0.8 to 0.0 times that of the undrawn yarn with a small single filament fineness. It is also important to keep the range within reach.

Only when these conditions are satisfied can a wool-like crimped yarn with excellent repellency be obtained.

Here, the cross-sectional shape of a fiber with a small single filament fineness does not change much whether it is circular or a modified cross-section. Figures 1 and 2 show a state in which a large number of fine, finely crimped yarns maintain a converged state and meander through the center of the mixed fiber bundle.

FIG. 1 is a side view, and FIG. 2 is a cross-sectional view of the mixed yarn bundle. As is clear from the figure, the fiber population with thin micro-crimps inhibits the collective crossover of the large fineness and irregular cross-section single yarns, so the mixed fiber yarn has unique bulk and repulsion. When made into a knitted fabric, it feels somewhat rough, but it has a wool-like texture with unique suppleness and firmness.
If the elongation of the thin single yarn fiber bundle is greater than the elongation of the thick single yarn, the fiber bundle will be in the opposite form to that shown in Figure 1, that is, the fiber bundle will be concentrated around the thick single yarn with slight crimp in the center. In addition, the thin single yarn fiber bundle becomes a wall-twisted yarn that is roughly crimped and entwined with the thick single yarn fiber bundle in the center while remaining almost in a bundled state. is also inferior and undesirable.

Here, fine crimp refers to gentle crimp with small difference in unevenness, and coarse crimp refers to large crimp with large difference in unevenness. Furthermore, if the blending ratio of the fiber bundle of thin single yarns is lower than the blending ratio of thick single yarns, it is undesirable that the rough stiffness increases and the repulsion property decreases.

When performing DTY processing on an undrawn yarn bundle in which undrawn yarns are aligned or spun and mixed, the stretching ratio is set to 0.0% of the elongation of the thin single yarn fiber bundle. When it exceeds Pi, thin single yarn fiber bundles are cut, multi-velocity fuzz occurs, and the entire yarn bundle is frequently cut.

Further, when the yarn is set to 0.8 times or less, the resistance passing through the false twisting spindle increases, and the entire yarn bundle may be cut, making processing impossible, which is undesirable. Example 1 Using a spinneret plate with 72 spinning holes, ηRel (relative viscosity measured at 20°C at a concentration of 0.5 g/100 ml in a mixed solvent of phenol and tetrachloroethane 1:1) was 1.380. Spinning temperature of polyethylene terephthalate 2
A spun plate having 126 denier 72 filament undrawn yarn with an elongation of 168% (Ef=1.68) obtained by spinning at 80°C and a winding speed of 2500 m/min and 12 water-type slit-shaped spinning holes. An undrawn yarn of 123 denier 12 filaments with an elongation of 274% obtained by spinning the above-mentioned polyethylene terephthalate at a spinning temperature of 280° C. and a winding speed of 2500 n1/min was aligned using the following conditions and subjected to DTY processing under the following conditions.

Stretching ratio (DR): 1.40 Number of false twists: 2000T/M 1st heater temperature: 180TC The processed yarn obtained was 178 denier, and the constituent single yarn was Hammoto.
It was a mixed fiber crimped yarn having a configuration as shown in FIGS. 1 and 2.

The texture of the double-knitted fabric was smooth to the touch, had supple repulsion, and had no glare or shine. Example 2 The undrawn yarn of Example 1 was pulled together to form a DRl. In step 4, the yarn was first drawn and blended, and the yarn was crimped while being false-twisted at 2000 T/M.

The obtained fibers and knitted fabrics were almost the same as those obtained in Example 1.

[Brief explanation of drawings]

Fig. 1 is a side view of the mixed fiber crimped yarn of the present invention, Fig. 2 is a cross-sectional view of the mixed fiber crimped yarn of the present invention, and Fig. 3 is a cross-sectional view of a modified cross-section with a large single yarn fineness used in the present invention. It is a sectional view showing an example of fiber.

Claims (1)

[Scope of Claims] 1. A fiber bundle of irregular cross-section consisting of fibers having a single yarn fineness in the range of 5 denier to 15 denier and having concave portions and pleated portions continuous in the longitudinal direction on the fiber surface, and a single yarn. The fiber bundle is composed of a fine yarn bundle with a fineness of 1.5 denier or less, and the irregular cross-section fiber bundle has coarse crimps and each single yarn exists separately,
The fine-grained yarn is a thermoplastic fiber characterized by having fine crimps, meandering around the center of the mixed yarn bundle in a bundled state, and threading between irregular cross-section fibers. A blended crimped yarn. 2. The mixed fiber crimped yarn according to claim 1, wherein the irregular cross-section fibers have a concave portion and a pleated portion that are continuous in the longitudinal direction of the fiber surface, and the number of pleats is 5 to 12. 3. When performing drawing and simultaneous false twisting on an undrawn yarn bundle containing a mixture of two types of thermoplastic fibers with different single filament finenesses, the fibers with a large single filament fineness are formed into concave portions that are continuous in the longitudinal direction on the fiber surface. When the fiber bundle with a small single filament fineness is Df and the elongation is Ef, and the fineness of a fiber bundle with a large single filament fineness is Db and the elongation is Eb, Df≧ When the conditions Db and Eb>Ef are satisfied, the stretching ratio D during stretching false twisting is
A mixed fiber winding characterized in that R and false twist number N are 0.9Ef>DR>0.8Ef 24000/√(D)>N (here, D is the total denier of the mixed fiber yarn after processing) A method for producing shrunken yarn. 4 Consisting of irregular cross-section fibers having a concave portion and pleats continuous in the longitudinal direction on the fiber surface with a single filament fineness of 5 to 15 denier after stretching, and fibers with a single filament fineness of 5 denier or less after stretching. The method for producing a mixed fiber crimped yarn according to claim 3, wherein the undrawn yarn bundle is subjected to stretching and simultaneous false twisting. 5 When the drawn bundles of two types of thermoplastic synthetic fibers with different single filament finenesses are aligned and subjected to false twisting, the fibers with large single filament finenesses are folded into concave portions and folds that are continuous in the longitudinal direction on the fiber surface. The number of false twists N is 240.
00/√(D)>N (where D is the sum of the deniers of two types of drawn yarn bundles) A method for producing a mixed fiber crimped yarn, characterized by satisfying the following condition. 6 A drawn yarn bundle consisting of irregular cross-section fibers having a single yarn fineness of 5 to 15 deniers and having concave portions and pleats continuous in the longitudinal direction on the fiber surface and fibers having a single yarn fineness of 5 deniers or less is temporarily drawn. A method for producing a mixed fiber crimped yarn according to claim 5, wherein the mixed fiber crimped yarn is twisted.