JPH0987940A - Conjugate yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a conjugate yarn giving a fabric having stiffness, toughness and springiness and high recoverability of wrinkles. SOLUTION: This conjugate yarn is composed of one or plural fiber bundles each containing filaments as the core part and short fibers as the sheath part. The filament has an elongation recovery of 95-100% (in 10% elongation), a flexural rigidity of >=2.5×10<-4> g.cm<2> and a single fiber fineness of 2-25d.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite yarn composed of a fiber bundle having a core-sheath structure, which is capable of producing a fabric having tension, waist, elasticity and easiness of wrinkle recovery.

[0002]

2. Description of the Related Art Conventionally, it is a problem experienced daily that wrinkles cannot be removed from clothes when worn or stored. This issue has been examined in the past,
For example, a hemp composite yarn in which a filament component is arranged in a core and hemp fibers and polyester staples are arranged in a sheath has been proposed as a hemp composite yarn to be used for a cloth for clothing (JP-A-60-110946). . The hemp composite yarn has properties such as natural feeling, tension, waist, and dry feeling peculiar to hemp when formed into a cloth, but is not yet sufficiently satisfactory in terms of wrinkle recovery. Further, as another method for solving the wrinkle recovery property, an ultrafine polyester woven fabric comprising polybutylene terephthalate fiber and ultrafine polyethylene terephthalate fiber (Japanese Patent Laid-Open No. 59-1999).
No. 173370), the wrinkle recovery property is improved, but the fabric tension, waist, and repellency are not sufficiently satisfactory.

Furthermore, a composite yarn in which a filament having a bending rigidity of a certain level or more is arranged in the core of a fiber bundle has been studied, but it is difficult to recover wrinkles once it is attached, although the resistance to wrinkles is improved.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, that is, the fact that the fabric is easily wrinkled or the wrinkles are difficult to be recovered, and while utilizing the characteristics of the short fibers arranged in the sheath component. The present invention is to provide a composite yarn for obtaining a fabric having excellent tension, elasticity, elasticity, and wrinkle recovery.

[0005]

The present invention takes the following means as a result of intensive studies to solve the above problems. That is, the present invention provides a composite yarn composed of one bundle or plural bundles of fiber bundles in which a filament is arranged in a core and a short fiber is arranged in a sheath,
The filament has an elongation recovery rate (at 10% elongation) of 95.
% -100%, flexural rigidity 2.5 × 10 ⁻⁴ g · cm ² or more, and single filament fineness of the filament is 2d-25
It is a composite yarn characterized by being d. It is also a preferable feature that the filament is made of a polypropylene terephthalate filament or a polybutylene terephthalate filament, and further that the filament is a non-circular cross-section yarn having the above characteristics.

In the present invention, the elongation recovery rate of the filament is particularly important and must be recovered by 95% or more at 10% elongation. It is more preferable that 100% recovery be achieved at 10% elongation. The higher the elongation recovery rate is, the better, and not only improves the wrinkle recovery property of the cloth, but also has the effect of improving the stretchability of the cloth. If the elongation recovery rate of the filament is less than 95% (at the time of 10% elongation), a fabric having excellent wrinkle recovery cannot be obtained, which is not preferable.

The elongation recovery rate here was determined by the following measuring method. That is, using a constant-speed elongation tensile tester (type RTM-250 manufactured by Orientec Co., Ltd.), a sample length of 20 cm, an initial load of 1/30 g per denier, and both ends fixed with air chucks, a tensile speed of 10% Elongate to 10% of sample length at a rate of / min (curve 1). After leaving for 1 minute, the weight is removed at the same speed and the initial state (gauge length 20c
Return to m) (curve 2). After left as it is for 3 minutes, elongation strain is applied again at a tensile rate of 10% / min. The load-elongation curve when the test is finished after 10% elongation is shown in FIG. The measurement is performed 5 times, the elongation recovery rate is calculated by the equation 1, and the average value is obtained.

[0008]

(Equation 1)

In the present invention, the bending rigidity of the filaments forming the core of the fiber bundle must be 2.5 × 10 ⁻⁴ g · cm ² or more. It is more preferable that the bending rigidity is 3.5 × 10 ⁻⁴ g · cm ² or more. The upper limit is not particularly limited, but there is a limit to the practically obtainable performance. Bending rigidity is 2.5
When it is less than 10 ⁻⁴ g · cm ² , not only the resistance to wrinkles of the fabric is insufficient, but also the tension, the waist and the repellency are insufficient, and a good texture cannot be obtained, which is not preferable.

The flexural rigidity (B) here is obtained by the equation 2 from the number of filaments (n), the moment of inertia of area (I) and the initial modulus (M).

(Equation 2) That is, the bending stiffness (B) can be calculated by the second moment of area (I) of the monofilament × the initial modulus (M),
It can be obtained by adding the number of filament constituents (n).

[0011] Incidentally, the second moment of the monofilament of a circular cross-section (I) is obtained by the [pi] D ^4/64,
D is the diameter (cm) of the monofilament, and it can be seen that the larger the fiber diameter, the larger the second moment of inertia (I).

Here, the cross-sectional shape of the filament may be non-circular in order to increase the second moment of area (I). For example, by making the cross-sectional shape hollow or multi-lobed even for filaments of the same fineness, the second moment of area (I) becomes high, and as a result, bending rigidity can be made high.

The initial modulus (M) referred to here was determined by the following measuring method. Using a constant-speed elongation tensile tester (RTM-250 type manufactured by Orientec Co., Ltd.), the sample length is set to 20 cm, and both ends are fixed with air chucks while applying an initial load of 1/30 g per denier. The measurement condition is a pulling speed of 10
Record the load-elongation curve at 0% / min. Obtained load-
A tangent line is drawn on the most inclined straight line portion of the elongation curve, and the stress per constant elongation is calculated from the inclination, and the initial modulus (g
/ Cm2).

In the present invention, as for the single yarn fineness (denier) of the filament constituting the core of the fiber bundle, the thicker one raises the second moment of area, but when the single yarn fineness exceeds 25d,
It takes time to cool during spinning, which is not preferable because the spinning equipment is restricted. Therefore, the upper limit of the single yarn fineness must be 25d. The upper limit of the single yarn fineness is more preferably 20d.

However, if the single yarn fineness is less than 2 denier, in order to satisfy the above bending rigidity, it is necessary to increase the number of filaments and increase the total denier to exceed 80 denier, resulting in a composite yarn. Becomes a thick count, which is not preferable because it is difficult to use in high-grade applications. Therefore, the lower limit of the single yarn fineness must be 2 denier.
The lower limit of the single yarn fineness is more preferably 5 denier.

In the present invention, the boiling water shrinkage of the filaments constituting the core of the fiber bundle must be 15% or less. If the boiling water shrinkage exceeds 15%, the filament will shrink considerably after passing through a heat treatment process such as a dyeing process with a fabric, and it becomes difficult to maintain sufficient elongation recovery after that, which is not preferable. .

The polypropylene terephthalate in the present invention is a polyester having terephthalic acid as a main dicarboxylic acid component and trimethylene glycol as a main glycol component, and having a trimethylene terephthalate unit as a main repeating unit, and its characteristics. In general, 10 mol% or less may be copolymerized with glycol such as ethylene glycol and butanediol, diphthalic acid such as isophthalic acid and 2,6-naphthalenedicarboxylic acid, etc. within a range that does not impair the above.

The polybutylene terephthalate in the present invention is a polyester having terephthalic acid as a main acid component and tetramethylene glycol as a main glycol component, and having a tetramethylene terephthalate unit as a main repeating unit, and its characteristics. In general, glycols such as ethylene glycol and propylene glycol, diphthalic acid such as isophthalic acid, and 2,6-naphthalenedicarboxylic acid may be copolymerized in an amount of 10 mol% or less within a range that does not impair the above.

Polypropylene terephthalate or polybutylene terephthalate is used as a starting material, which is spun and stretched under the conditions that can be usually set, so that it has an excellent elongation recovery property and an appropriate flexural rigidity. The filament suitable for the core of the fiber bundle of the present invention can be easily manufactured.

The polypropylene terephthalate and the polybutylene terephthalate described in the present invention are the same as those in the polypropylene terephthalate and the polybutylene terephthalate as long as they do not impair the physical properties.
A modifier such as an antioxidant or a flame retardant may be included.

The number of filaments constituting the core of the fiber bundle may be one or may be two or more, and the total denier is, for example, about 10 to 80 denier. The number of filaments is preferably 1 to 15. As an example, 20d / 1f, 20d / 2f, 3
0d / 2f, 40d / 4f etc. are mentioned. Further, the filament is preferably present in the fiber bundle in an amount of 2% by weight to 60% by weight, more preferably 10% by weight to 40% by weight.

On the other hand, the short fibers constituting the sheath of the fiber bundle are
There is no particular limitation as long as it can be used in a normal spinning process. For example, it is possible to use cotton or polynosic fiber. Alternatively, one kind or two or more kinds of polyethylene terephthalate short fibers may be used, and the fiber length thereof can be appropriately selected within a range of 20 to 180 mm.
Further, the thickness is practically about 0.5 to 10 d.

In the present invention, the twist coefficient K (inch system) of the entire composite yarn is in the range of 1.5 to 9.0 in order to maintain the integrity and texture of the short fiber component and the filament component. Is preferred. A more preferable twist coefficient K is in the range of 3.0 to 7.0. If the twist coefficient is less than 1.5, the tightness of the yarn tends to be unsatisfactory, and the pilling resistance of the fabric will be slightly inferior. Also 9.
When it exceeds 0, the anti-pilling property of the single yarn comes to occur, and the passability in the subsequent process becomes poor. The twist coefficient is calculated by the following formula.

(Equation 3)

The form of the composite yarn of the present invention is not particularly limited. For example, it may be composed of one fiber bundle or two or more fiber bundles. Furthermore, the sheath component of the fiber bundle having the core / sheath structure of the present invention may be formed in two layers. For example, as shown in FIG. 2, a filament (F) in the core, a fiber bundle (A) in which short fibers (SA) are arranged in the sheath, and a fiber bundle consisting only of short fibers of the sheath component of the fiber bundle (A). The composite yarn in which the actual twist is applied so as to be wrapped around with (B) is preferable in that the sheath component has two layers and the coverage of the filament component is improved.

[0025]

Embodiments of the present invention will be described below with reference to examples. The relative viscosity was measured at 30 ° C. using a mixed solvent of p-chlorophenol and tetrachloroethane in a weight ratio of 3: 1. Solution concentration is 0.4
g / dl.

[0026]

【Example】

Example 1 Polypropylene terephthalate (PPT) having a relative viscosity of 1.39 was melted at 260 ° C., extruded from a circular nozzle hole, temporarily wound at a winding speed of 1300 m / min, and stretched 2.8 times. By heat setting, the filaments (20d / 2
f) was obtained. The filament is the core, and the polynosic short fibers (thickness 1.0d, cut length 38 mm) are arranged in the sheath.
0'S (English cotton count) was manufactured with a twist coefficient of 3.7. A woven fabric (2/1 twill) woven and dyed using the composite yarn as a warp yarn (woven density 146 yarns / inch) and a weft yarn (woven density 77 yarns / inch) has tension, waist and elasticity. However, the wrinkle recovery was also excellent. Table 1 shows those characteristic values.

Example 2 Polybutylene terephthalate (PBT) having a relative viscosity of 1.56 was melted at 260 ° C. and extruded through a circular nozzle hole, and a winding speed was set to 130.
It was wound up at 0 m / min, stretched 2.6 times, and heat set to obtain filaments (2
0d / 2f) was obtained. Then, a woven fabric was obtained in the same manner as in Example 1 except that this filament was used as the core of the composite yarn.
The obtained woven fabric was excellent in wrinkle recovery while having tension, waist and elasticity. Table 1 shows those characteristic values.

(Example 3) Polybutylene terephthalate (PBT) having a relative viscosity of 1.56 was melted at 260 ° C. and extruded through a modified nozzle hole as shown in FIG. 3, and a drawing speed was 1300 m / min. A filament having a four-lobed cross section shown in Table 4 was once wound up, stretched 2.3 times, and heat-set to obtain a filament (20d / 2f) as shown in Table 1. Then, a woven fabric was obtained in the same manner as in Example 1 except that this filament was used as the core of the composite yarn. The obtained woven fabric was excellent in wrinkle recovery while having tension, waist and elasticity. Table 1 shows those characteristic values.

Example 4 Polybutylene terephthalate (PBT) having a relative viscosity of 1.56 was melted at 260 ° C. and extruded through a circular nozzle hole, and a winding speed was set to 130.
It was wound at 0 m / min, stretched 2.8 times, and heat set to obtain filaments (1
0d / 1f) was obtained. Then, this filament is used as the core, and polynosic short fibers (thickness 1.0d, cut length 38
mm) is arranged in the sheath, and the mixing ratio of the filaments is 11% by weight.
A 60'S / 2 composite yarn was produced with a twisting factor of 3.7 by combining the two fiber bundles. The coverage of the composite yarn was excellent. Example 1 except that the composite yarn was used
A woven fabric was obtained in the same manner as in. The obtained woven fabric was excellent in wrinkle recovery while having tension, waist and elasticity. Table 1 shows those characteristic values.

Example 5 A filament (20d / 2f) as shown in Table 1 was obtained from polybutylene terephthalate (PBT) having a relative viscosity of 1.56. With this filament (F) as the core, polynosic staple fibers (S
The surface of the composite fiber bundle (A) arranged so that A) is arranged in the sheath is further arranged so that the sheath component as shown in FIG. 2 in which the fiber bundle (B) of only polynosic fibers is incorporated becomes two layers. Composite yarn 30 'having a mixed filament content of 11% by weight
S was produced with a twist factor of 3.7. The coverage of the composite yarn was very good. A woven fabric was obtained in the same manner as in Example 1 except that the composite yarn was used. The resulting woven fabric has tension, waist,
While having elasticity, it was also excellent in wrinkle recovery. Table 1 shows those characteristic values.

Comparative Example 1 Polyethylene terephthalate (PET) having a relative viscosity of 1.43 was melted at 300 ° C. and extruded through a circular nozzle hole, and a winding speed was 100.
It was wound up at a rate of 0 m / min, stretched 3.8 times, and heat set to obtain filaments (2
0d / 2f) was obtained. Then, a woven fabric was obtained in the same manner as in Example 1 except that this filament was used as the core of the composite yarn.
The obtained woven fabric had tension, waist and elasticity, but was inferior in wrinkle recovery. Table 1 shows those characteristic values.

(Comparative Example 2) Polybutylene terephthalate (PBT) having a relative viscosity of 1.56 was melted at 260 ° C. and extruded through a circular nozzle hole, and a winding speed was 130.
It was wound up at a rate of 0 m / min, stretched 1.8 times, and heat set to obtain filaments (3
0d / 20f) was obtained. Then, a woven fabric was obtained in the same manner as in Example 1 except that this filament was used as the core of the composite yarn. The obtained woven fabric has tension, waist and elasticity,
Wrinkle recovery was also excellent. The characteristic values are shown in Table 1.

(Evaluation Method) Each characteristic value shown in the examples and comparative examples was evaluated by the following methods. (1) Tension, waist, repellency, and covering property Measurement method: Sensory test evaluated good, good, fair, and bad in three grades by 7 persons, and indicated by the most evaluated grade. It was (2) Wrinkle recovery rate Measurement method: Based on the dry B method (Monsanto method) described in JIS-1059, wrinkle recovery rate (%) = (α / 180) × 100.

[0034]

【table 1】

[0035]

INDUSTRIAL APPLICABILITY As described above, according to the composite yarn of the present invention, it is possible to provide a composite yarn which is excellent in tension, elasticity, resilience, and wrinkle recovery, and which can produce an unprecedented fabric. can do.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a load-elongation curve when obtaining the elongation recovery rate of the filament of the present invention.

FIG. 2 is a schematic cross-sectional view of a composite yarn shown in an example of the present invention.

FIG. 3 is a cross-sectional view showing an example of a non-circular nozzle hole used in Example 3 of the present invention.

FIG. 4 is a cross-sectional view of an undrawn yarn obtained in Example 3 of the present invention.

[Explanation of symbols]

 L Elongation at 10% elongation (mm) ΔL Residual strain (mm) 1 1st elongation curve 2 Recovery curve after unloading 3 2nd elongation curve

Claims (4)

[Claims] 1. A composite yarn comprising one or a plurality of fiber bundles in which a filament is contained in a core and a short fiber is arranged in a sheath, and the filament has an elongation recovery rate (at 10% elongation).
95% to 100%, flexural rigidity of 2.5 × 10 ⁻⁴ g · cm ² or more, and single filament fineness of the filament is 2 d to
25d is a composite yarn. 2. The filament is a polypropylene terephthalate filament.
The described composite yarn. 3. The composite yarn according to claim 1, wherein the filament is a polybutylene terephthalate filament. 4. The composite yarn according to claim 1, 2 or 3, wherein the filament has a non-circular cross-sectional shape.