JP2637966B2 - Highly stretchable, finely processed yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention has excellent stretchability in which individual polyamide filaments have a thick portion and a thin portion, and when dyed into a woven or knitted fabric, a difference in light and shade dyeing appears. The present invention relates to a crimped multifilament yarn, and particularly to a highly stretchable and finely processed yarn suitable for a woven fabric having a warp or weft or a stretchable weft.

(Prior Art) Conventionally, many false twisted yarns having unevenness in thickness and a difference in dyeing ability in the longitudinal direction of a yarn have been proposed. For example,
No. 7207. JP-B-53-27387. 53-360
No. 51, JP-B-53-45418, JP-B-58-12946, JP-B-58-37417, JP-B-50-5686, JP-B-59-2003, and JP-A-59-59926. Japanese Patent Application Publication No. JP-A-2005-64139 discloses a crimped yarn having a density difference in the longitudinal direction of a yarn obtained by false twisting a polyether multifilament yarn having unevenness in the longitudinal direction of the yarn.

(Problems to Solve the Invention) However, these processed yarns are excellent in terms of feeling and surface effect, but have low stretchability due to crimping and are insufficient in functions such as stretchability. However, it was difficult to apply to stretchable fabrics. The stretchable woven fabric usually means a woven fabric having an elongation ratio of 20% or more, but the woven fabric obtained from these processed yarns could not satisfy this.

An object of the present invention is to solve the above-mentioned conventional drawbacks, and an object of the present invention is to provide a high-stretch, finely-processed yarn having both a surface effect based on a color difference in shade and a high-stretch functionality. .

(Means for Solving the Problems) The present inventors have arrived at the present invention as a result of intensive studies to solve the above-mentioned drawbacks of the conventional technology.

That is, according to the present invention, the birefringence (Δn) is 15 × 10 ⁻³ to 30.
× 10 ^-3 undrawn polyamide yarn, heat treatment temperature 110 ℃ ~ 200
℃, feed rate -20% ~ + 20% heat treatment to reduce the crystallinity
35% or more, and then heat-treated undrawn yarn is drawn at a draw ratio of 1.2 to 3.0 times to form a multi-filament yarn consisting of filaments whose cross-sectional area varies in the fiber axis direction. Twist number 15000 / D ^1/2
(T / M) to 38000 / D ^1/2 (T / M) (D is multifilament yarn denier), obtained by false twisting at a false twist temperature of 120 ° C to 210 ° C, in the fiber axis direction A crimped multifilament yarn comprising a polyamide filament having a cross-sectional area ratio of 1.2 to 4.0 between a thick portion and a thin portion, wherein the stretch ratio is 50% or more. The gist of the present invention is a highly stretchable and finely processed yarn having a difference in dyeing ability in each direction.

 Hereinafter, the present invention will be described in detail.

First, the cross-sectional area of the highly stretchable and finely processed yarn of the present invention varies in the fiber axis direction, and the cross-sectional area ratio of the thick part to the thin part is 1.2.
It is a crimped multifilament yarn comprising a polyamide filament of ~ 4.0. Here, when dyeing a woven fabric using a crimped multifilament yarn having a filament cross-sectional area ratio of less than 1.2, a sufficient shade difference cannot be obtained and an effective surface effect cannot be obtained. On the other hand, the cross-sectional area ratio of filament was 4.
If the value exceeds 0, the yarn fineness becomes unnecessarily large due to the overlapping of the thick part of the filament. Therefore, when dyeing a woven fabric using the crimped multifilament yarn, the deeply dyed part is overemphasized and the surface is uneven. This is not preferable because the intensely stained portion is easily worn when worn. When the cross-sectional area ratio of the filament is in the range of 1.2 to 4.0, in the case of a yarn in which the phase of the thick part between the filaments is relatively uniform,
In the case of yarns with slabs and other irregularities given to the fabric by emphasizing the width and width, and in the case of yarns with irregular phases between filaments, smooth irregularities and particularly deep color tones due to differences in the form of yarn spots are obtained. In each case, a woven fabric having a favorable surface effect can be obtained. In particular, in order to obtain a clear color difference and to prevent the abrasion of the projections on the woven product, the cross-sectional area ratio of the filament must be adjusted.
1.5 to 3.0 is more preferable.

Here, the cross-sectional area ratio of the filament is determined by taking out the filament that composes it from the multifilament yarn, photographing the cross sections of the thick part and the thin part at 30 places each with an optical microscope, and averaging the cross-sectional area of the thick part and the thin part. It is calculated from the average value of the cross-sectional area of the part.

Next, the highly stretchable and finely processed yarn of the present invention has a stretchable elongation rate of
It needs to be at least 50%.

Since the polyester fiber has a benzene ring in the molecular chain, it has low flexibility and high Young's modulus. For this reason, even if the polyester multifilament yarn is false-twisted and crimped, the expansion and contraction rate due to crimping is usually about 10%.
It is as low as 15% at the maximum. In order to increase the expansion and contraction rate due to this crimp, it is necessary to increase the elasticity of the fiber by not having a molecular structure such as a benzene ring in the molecule that inhibits the flexibility of the fiber and having hydrogen bonds at appropriate length intervals. Polyamide fiber yarns such as nylon 6, nylon 6.6, and nylon 6.10. When a crimped yarn made of a polyamide fiber is used, a performance of 50% or more in elongation and contraction can be easily obtained.

If the stretch rate of the processed yarn is set to 50% or more, the stretch rate becomes 20%.
% Can be easily obtained, and can be applied to functional clothing such as sports clothing that requires a high degree of elasticity.

In the present invention, the stretch ratio is measured by a JIS-L-1090.5.7 synthetic fiber filament bulky processed yarn stretchable C method (without wet heat treatment). The elongation rate of the woven fabric is JIS-L-10
96.6.14 Stretch property of stretch fabric 6.14.

Next, the method for producing the highly stretchable and finely processed yarn of the present invention will be described.

First, a polyamide undrawn yarn having a birefringence Δn of 15 × 10 ⁻³ to 30 × 10 ⁻³ is heated at a temperature of 110 ° C. to 200 ° C. and a feed rate of −20 so as to increase the crystallinity to 35% or more. % To + 20%. Here, the feed rate is a percentage of the difference between the supply speed and the take-up speed with respect to the take-up speed.

As the supply yarn, it is necessary to use a polyamide undrawn yarn having a birefringence Δn of 15 × 10 ⁻³ to 30 × 10 ^{−3, and} a polyamide undrawn yarn having a birefringence Δn of less than 15 × 10 ⁻³ is used. If it is used, it becomes brittle due to heat treatment, and thread trimming occurs in the subsequent false twisting, making it difficult to process. On the other hand, the birefringence Δn is 30 × 10
^If a polyamide undrawn yarn exceeding ^-3 is used, non-uniform drawing accompanied by netting cannot be performed even when drawing is performed in the subsequent heat treatment, and a filament having a cross-sectional area that varies in the fiber axis direction cannot be obtained.

In order to stretch polyamide undrawn yarn unevenly, it is necessary to increase the crystallinity to 35% or more unlike polyester undrawn yarn.

If the degree of crystallinity is 35% or more, many crystal blocks are formed in the structure of the polyester undrawn yarn, and the crystal blocks act to prevent uniform drawing during drawing, causing non-uniform drawing. It is possible. Therefore, in order to increase the crystallinity of the supply yarn to 35% or more, it is necessary to perform heat treatment at a heat treatment temperature of 110 ° C to 200 ° C and a feed rate of -20% to + 20%. If the heat treatment temperature is lower than 110 ° C, the crystallinity cannot be increased to 35% or more.
When the temperature is higher than 00 ° C., the filament is melted, and the yarn breakage and the embrittlement are likely to occur. When the feed rate is less than -20%, the birefringence Δn is 30 × 10 ⁻³ due to a strong elongation effect.
As described above, uneven stretching cannot be performed in subsequent stretching. When the polyamide undrawn yarn is heat-treated, the heat-treated yarn is subjected to a condition in which the birefringence greatly increases beyond 30 × 10 ^-3 due to the heat treatment, for example, heat treatment is performed while giving a high elongation. Even if it is stretched, non-uniform stretching cannot be performed. The reason is that the birefringence Δ
When n substantially increases to 30 × 10 ^-3 or more, the molecular chains are already elongated, and regardless of the degree of crystallinity, the non-uniform stretching that occurs during the structural transition process from a bulk structure to a bundle structure occurs. This is because they cannot be generated. On the other hand, if the feed rate exceeds + 20%, the heat-shrinkage of the polyamide undrawn yarn becomes insufficient, and the yarn tends to sag, making it difficult to process. The above heat treatment is performed at a heat treatment temperature of 130
C. to 180.degree. C., preferably at a feed rate of -5% to + 5%. In the subsequent drawing, a non-uniform drawing can be performed in a particularly stable state, and a yarn having a distinct thickness unevenness is obtained. Can be

Next, the heat-treated polyamide undrawn yarn is drawn at a draw ratio of 1.2 to 3.0 times, and netting is generated in each of the filaments, thereby obtaining a multifilament yarn comprising a filament whose cross-sectional area varies in the fiber axis direction. In other words, non-uniform stretching is performed by stretching at a draw ratio of 1.2 to 3.0 times, and a multifilament yarn consisting of a filament whose cross-sectional area varies in the fiber axis direction and the cross-sectional area ratio of the thick part to the thin part is 1.2 to 4.0. Form. Here, if the stretching ratio is less than 1.2 times, it is difficult to carry out uneven stretching, and even if uneven stretching occurs, what is recognized as a filament having unevenness in thickness is not formed. On the other hand, when the draw ratio exceeds 3.0 times, the thick portion disappears due to drawing, it is easy to form a uniform drawn yarn, and it is difficult to obtain a filament whose cross-sectional area fluctuates in the fiber axis direction. It depends on the birefringence, crystallinity, etc. of the undrawn yarn after heat treatment.
In order to obtain a filament having a moderate unevenness in thickness, for example, to obtain a filament having a cross-sectional area ratio of 1.5 to 3.0, it is preferable to employ a stretching ratio of 1.5 to 2.5 times.

In the above stretching, it is preferable to perform cold stretching, particularly at room temperature, in order to cause uneven stretching. Especially,
It is effective to carry out drawing at room temperature in order to obtain a filament consisting of filaments having a distinct thickness unevenness. However, it is also possible to stretch under heating in order to easily control the phase of the thick part, the length, the frequency, etc. of the thick part. However, in order to perform non-uniform drawing under heating, the drawing temperature should be equal to or lower than the glass transition temperature (Tg) of the heat-treated undrawn yarn + 20 ° C.

After that, the multifilament yarn consisting of the filaments whose cross-sectional area varies in the fiber axis direction obtained by the above-mentioned drawing is false-twisted. It is necessary to perform false twisting at a false twist temperature of 120 ° C to 210 ° C. Here, D is the denier of the multifilament yarn obtained by the above drawing. The number of false twists If it is less than 50%, it is difficult to obtain a processed yarn with an elongation of 50% or more.
on the other hand, When the value exceeds, the thick portion is elongated due to the yarn breakage due to the twist break or the strong torsional deformation, and it is difficult to form a clear thickness unevenness. In particular, in order to obtain stable processing operability and high expansion and contraction rate Is preferred. When the false twist temperature is lower than 120 ° C, the crimp is not fixed, and it is difficult to obtain a processed yarn having an expansion / contraction rate of 50% or more. On the other hand, when the false twist temperature exceeds 210 ° C, fusion between the filaments is likely to occur. After all, it is difficult to obtain a processed yarn with an expansion / contraction rate of 50% or more. In particular, in order to obtain a high stretch rate,
It is preferred to employ a false twist temperature of ° C.

The crystallinity was measured by the density gradient tube method.
It is calculated from the following equation.

Where Xc: crystallinity [crystallinity; 100Xc (%)] d: density of measurement sample (g / cm ³ ) dc: density of perfect crystal part (g / cm ³ ) da: density of perfect amorphous part (G / cm ³ ) Here, in the case of nylon 6, dc = 1.230 g / cm ³ , da = 1.
084 g / cm ³ . Next, a method for producing a highly stretchable and finely processed yarn of the present invention will be described with reference to FIG.

The undrawn polyamide yarn 2 drawn from the spool 1
It is supplied to a heat treatment area by a feed roller 3, where it is heat treated by a heat treatment heater 4, and then cold drawn between a delivery roller 5 and a drawing roller 6 at room temperature. Next, the yarn exiting the drawing roller 6 is subjected to false twist crimping by a false twist heater 7 and a false twist twisting device 8, taken up by a delivery roller 9, and wound up by a winding roller 10 on a cheese 11.

In the above example, an example in which all the steps are processed continuously is shown, but it may be supplied to the next step after being wound up once in the heat treatment step or the stretching step. In addition, the false twist twisting device 8
Usually, a mechanical spindle is used, but a false spindle or a false twisting and twisting device using a fluid nozzle that generates a swirling flow may be used.

The highly stretchable and finely processed yarn of the present invention is most suitable for stretchability, but may be used for other woven fabrics or twisted and woven with other yarns. Further, the present invention can be appropriately applied not only to knitted fabrics particularly requiring elasticity such as swimwear but also to other knitted fabrics.

(Operation) The highly stretchable finely-processed yarn of the present invention is a crimped multifilament yarn composed of a polyamide filament having a cross-sectional area ratio of 1.2 to 4.0 between a thick portion and a thin portion. Appropriate, less occurrence of warping, thread cutting, fluffing, etc. during weaving, excellent in practicality, and capable of satisfying shade effect of light and shade. Furthermore, since the stretch ratio is 50% or less, a woven or knitted fabric with extremely high elasticity can be obtained, and can be applied to possible clothing such as sports clothing requiring a high degree of elasticity.

(Examples) Next, the present invention will be described specifically with reference to examples.

Example 1 Birefringence 19.5 × 10 ⁻³ , crystallinity 30.2% (density 1.1244 g / c
m ³ ) Nylon 6 multifilament undrawn yarn 267d / 24f
According to the process shown in Fig. 1, heat treatment, cold drawing (drawing temperature is room temperature of 25 ° C), and false twisting are performed under the conditions shown in Table 1. A crimped multifilament yarn consisting of a thick and thin filament having a cross-sectional area ratio of 1.85 of the thin portion was obtained. However, a mechanical spindle was used as the false twisting and twisting device.

The birefringence and crystallinity of the yarn after heat treatment were measured. The birefringence was 21.5 × 10 ^-3 and the crystallinity was 40.3%.
(Density: 1.1386 g / cm ³ ).

The obtained high-elasticity thick and thin yarn was used as a warp having a density of 108 per 2.54 cm of reed, and 88 wefts per 2.54 cm with a density of 2.54 cm with a surface texture of 2/2 and a back texture of 3/1. And then dyed in a conventional manner.

The obtained stretchable fabric had a heather appearance due to the difference in shades of color on the surface, and had a performance of 43% elongation in the weft direction.

Example 2 Birefringence 22.0 × 10 ⁻³ , crystallinity 32.6% (density 1.1276 g / c
m ³ ) Nylon 6 multifilament undrawn yarn 193d / 16f
After the heat treatment under the conditions shown in Table 2, cold stretching (stretching temperature of 25
(Room temperature of ° C.), and once wound, and then false twisted to obtain a crimped multifilament yarn having the quality shown in Table 2.

The birefringence and crystallinity of the yarn after heat treatment were measured and measured. The birefringence was 23.1 × 10 ^-3 and the crystallinity was 43.0%.
(Density: 1.1423 g / cm ³ ).

FIG. 2 shows the structure of the obtained highly elastic thick and thin yarn, which is 110 yarns per 2.54 cm warp density and 103 yarns per 2.54 cm weft density.
It was woven in a book and then dyed and finished by a conventional method.

The stretchable fabric obtained had a heather appearance due to the difference in shades of light and shade, and had a stretch ratio of 35% in the warp direction and 43% in the weft direction.

(Effect of the Invention) Since the highly stretchable and finely textured yarn of the present invention has the above-described structure, a preferable surface effect due to the difference in shade of shade is obtained, and the stretch and elongation is as high as 50% or more. In the case of woven or knitting, a functional woven fabric having excellent elasticity can be obtained, and can be applied to functional clothing such as sports clothing requiring high elasticity.

[Brief description of the drawings]

FIG. 1 is a schematic process diagram showing a method for producing a highly stretchable and finely processed yarn of the present invention, and FIG. 2 is an organization diagram showing an example of a woven fabric comprising the highly stretchable and thinly processed yarn of the present invention. 2; undrawn polyamide yarn 4; heat treatment heater 7; false twist heater 8; false twist twisting device

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-56-144221 (JP, A) JP-A-57-77333 (JP, A) JP-A-57-66129 (JP, A) 94622 (JP, A) JP-A-50-101608 (JP, A) JP-B-59-20003 (JP, B2)

Claims (1)

(57) [Claims] 1. An undrawn polyamide yarn having a birefringence (Δn) of 15 × 10 ⁻³ to 30 × 10 ⁻³ is heat-treated at a heat treatment temperature of 110 ° C. to 200 ° C. and a feed rate of −20% to + 20% to form a crystal. Degree of conversion to 35% or more, and then heat-treated undrawn yarn is drawn at a draw ratio of 1.2 to 3.0.
A multifilament yarn consisting of filaments with a cross-sectional area that fluctuates in the fiber axis direction after being stretched by a factor of 2. After that, the multifilament yarn is false-twisted at 15,000 / D1 / ² (T / M) to 3
8000 / D ^1/2 (T / M) (where D is multifilament yarn denier), obtained by false twisting at a false twist temperature of 120 to 210 ° C. A crimped multifilament yarn composed of a polyamide filament having a cross-sectional area ratio of 1.2 to 4.0 between a thick part and a thin part, and has a stretchability of 50% or more, characterized by a longitudinal dyeing ability. Highly stretchable and finely processed yarn with a difference.