JP4699072B2 - Stretch polyester composite fiber - Google Patents

Description

  The present invention is a composite fiber composed of two types of polyester components having different viscosities, and has a spiral-like manifested crimp and has a latent crimp performance, thereby providing a feeling of swelling and stretch back, Relates to a stretchable polyester composite fiber that can obtain a fabric having excellent surface smoothness with no embossing defects.

  Polyesters represented by polyethylene terephthalate have excellent mechanical and chemical properties and are used in a wide range of fields. As one of the applications, in order to obtain a woven or knitted fabric having a stretch function, two types of polyesters having different heat shrinkage characteristics are joined to a side-by-side type, and the potential to develop crimping performance by heat received during processing after knitting and weaving. It is well known to use crimped conjugate fibers (see Patent Documents 1 and 2).

  Such a fiber having latent crimping property is suitable for expressing a soft texture by imparting a bulkiness to a woven or knitted fabric by expressing the crimp after weaving and weaving, giving a feeling of swelling. Fiber. These latent crimped fibers can be used alone (100% use) after being processed into a woven or knitted fabric, but they can be used together with various other fibers while taking advantage of the characteristics of the partner fiber to be combined. It becomes possible to impart stretch properties and is used for many purposes.

  However, when a fiber having latent crimpability is used alone (100% use) to obtain a woven or knitted fabric, there is a problem that a wrinkle standing defect occurs and the surface smoothness deteriorates.

As a method for solving such a problem, it is conceivable to reduce the single yarn fineness of a fiber having latent crimpability. However, when the single yarn fineness is lowered, the surface smoothness is improved, but there is a problem that the crimping performance is remarkably lowered and sufficient stretchability cannot be obtained. Thus, the fiber which can provide both surface smoothness and stretch property to the obtained fabric has not been proposed yet.
Japanese Patent Laid-Open No. 11-241229 JP 2000-212838 A

  The present invention solves the above-mentioned problems, and it is a technical problem to provide a stretchable polyester fiber capable of obtaining a fabric that is excellent in both surface smoothness and stretchback without wrinkles. To do.

  The inventors of the present invention have arrived at the present invention as a result of intensive studies to solve the above problems.

That is, the present invention comprises 2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane and a sulfonic acid base compound or isophthalic acid component in a total amount of 5 to 20 mol% and a high viscosity polyester component and ethylene terephthalate. A composite fiber having a single yarn fineness of 0.5 to 4.0 dtex in a single yarn shape in which low-viscosity polyester components as main repeating units are bonded to each other in a side-by-side type or an eccentric core-sheath type, and having a spiral shape A stretchable polyester composite fiber characterized by having an apparent crimp ratio (C0) and a latent crimp ratio (C100) satisfying the following values at the same time.
0 <C0 ≦ 5
30 ≦ C100 ≦ 60
The actual crimp rate: C0 (%) = [(L0−L1) / L0] × 100
Potential crimp rate: C100 (%) = [(A0−A1) / A0) × 100
L1: The length of the lash measured after the fiber was pulled while applying a tension of 90.91 × 10 ^-3 cN / dtex and the load was applied to the heel with a load of 1.67 × 10 ^-4 cN / dtex for 30 minutes. L0: After measuring L1,枷 Length A1 measured by changing the load from 1.67 × 10 ^-4 cN / dtex to 90.91 × 10 ^-3 cN / dtex: Remove the fiber while applying a tension of 90.91 × 10 ^-3 cN / dtex,枷 Length measured after boiling water treatment for 30 minutes while applying a load of × 10 ^-4 cN / dtex, after applying a load of 1.76 × 10 ^-3 cN / dtex and left to stand for 30 minutes A0: After measuring A1, the load is 1.76 ×枷 Length measured from 10 ^-3 cN / dtex to 4.4 × 10 ^-2 cN / dtex

  The stretchable polyester conjugate fiber of the present invention has a spiral-like manifest crimp, and the crimp ratio of the latent crimp and the crimp ratio of the latent crimp expressed by hydrothermal treatment are within an appropriate range. Therefore, by knitting or weaving, it is possible to obtain a fabric that is excellent in both surface smoothness without stretch and stretch back.

Hereinafter, the present invention will be described in detail.
The conjugate fiber of the present invention is a conjugate fiber having a single yarn shape in which two types of polyester components (high viscosity polyester component and low viscosity polyester component) having different viscosities are bonded to each other in a side-by-side type or an eccentric core-sheath type. is there.

  That is, each single yarn constituting the composite fiber is a cross-sectional shape in which two types of polyester components are bonded to a side-by-side type or an eccentric core-sheath type. The side-by-side type refers to FIG. As shown in Fig. 1, there are two types of polyester components that are bonded together in a straight line, and the bonded surfaces are bonded almost equally, and those in which the bonded surfaces are curved and bonded as shown in Fig. 1 (B). Can be mentioned. As shown in FIG. 2, the eccentric core-sheath type means that one component is a sheath and the other component is a core, and the centers of the core portion and the sheath portion do not coincide. In the present invention, the sheath part is preferably a low viscosity component and the core part is preferably a high viscosity component.

The high-viscosity polyester component is mainly composed of polyethylene terephthalate (hereinafter, abbreviated as PET) having ethylene terephthalate as a main repeating unit, and the ethylene terephthalate repeating unit may be a PET having 90% or more. preferable. And it is necessary for PET to contain 2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane and a sulfonate group compound or an isophthalic acid component.

By containing these 2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane and a sulfonate group compound or an isophthalic acid component , the high-viscosity polyester component has a high thermal shrinkage rate, and the low-viscosity polyester component The difference in heat shrinkage rate between the fibers can be increased, and as a result, the latent crimp rate of the entire fiber can be increased. That is, the latent crimp rate can be increased without increasing the intrinsic viscosity difference between the high viscosity polyester component and the low viscosity polyester fiber.

2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane and the sulfonate group compound or isophthalic acid component must be contained in a total amount of 5 to 20 mol% in the high-viscosity polyester component , Among these, the content is preferably 6 to 15 mol%. In order to contain these components, it is preferable that they are copolymerized with PET, but they may be blended (mixed).

  If these contents are less than 5 mol%, it is difficult to obtain a sufficient effect of improving the potential crimping performance. On the other hand, if the contents exceed 20 mol%, the spinnability is impaired or the fiber strength is impaired. It is not preferable.

  Among them, 2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane is preferably contained in an amount of 1 mol% or more in the high-viscosity polyester component because it has a large effect of improving heat shrinkability. It is preferable to contain more than mol%.

Further, the high-viscosity polyester component needs to contain either a sulfonate group compound or isophthalic acid in addition to 2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane .

  As the sulfonate group compound, 5-sodium sulfoisophthalic acid is particularly preferable. The content of the sulfonate group compound is preferably 1 mol% or more, and the content of isophthalic acid is preferably 2 mol% or more.

  The low-viscosity polyester component that constitutes the conjugate fiber of the present invention is not particularly limited as long as it is mainly composed of PET, but it should be a PET in which the repeating unit of the ethylene terephthalate component is 95% or more. Is preferred. In order to make the heat shrinkability lower than that of the high-viscosity polyester component, those containing a component that greatly inhibits the crystallinity, or 2,2-bis {4- (Β-) contained in the high-viscosity polyester component. Those containing hydroxyethoxy) phenyl} propane, sulfonate group compounds, isophthalic acid and the like are not preferred.

  In addition, both polyester components contain a small amount of other components such as matting agents, antioxidants, UV absorbers, pigments, flame retardants, antibacterial agents, and conductivity-imparting agents, as long as the essential properties are not impaired. You may do it.

In the conjugate fiber of the present invention, two types of polyester components having different viscosities are used. The difference between the intrinsic viscosity of the high-viscosity polyester component and the intrinsic viscosity of the low-viscosity polyester component is 0.05 to 0.3. Is preferable, and 0.07 to 0.25 is particularly preferable.
Here, the intrinsic viscosity is a value measured at 20 ° C. using a Ubbelohde viscometer after dissolving polyester in a 1: 1 mixed solvent of phenol and tetrachloroethane.

  When the difference in intrinsic viscosity is less than 0.05, the expression of crimping performance tends to be insufficient, and it becomes difficult to obtain a fabric having a sufficient feeling of swelling and stretchback performance. On the other hand, if the difference between the intrinsic viscosities exceeds 0.3, when the composite flow of both polyesters is discharged from the spinneret, the bending becomes large, and the spun polymer (yarn) adheres to the spinneret and is cut. Tends to occur and it becomes difficult to perform stable spinning.

  The ratio of both components of the composite fiber is preferably in the range of 40/60 to 60/40 in terms of mass ratio (high viscosity polyester component / low viscosity polyester component) in order to obtain good crimping performance. If it is outside this range, it will be difficult to develop sufficient crimping performance.

The single yarn fineness of the composite fiber of the present invention is required to be 0.5 to 4.0 dtex, and preferably 0.8 to 3.0 dtex. When the single yarn fineness is less than 0.5 dtex, the expression of the crimping performance becomes insufficient, and it becomes difficult to obtain a fabric having sufficient stretch back performance, and the yarn adheres to the spinneret during spinning. This makes it easier to spin stably. On the other hand, when the single yarn fineness exceeds 4.0 dtex, it becomes difficult to obtain good softness.

  Next, the actual crimp and the latent crimp of the composite fiber of the present invention will be described. First, the conjugate fiber of the present invention has an actual crimp, and this actual crimp is spiral. That is, the spiral crimp is a crimp in which the shape of the crimp exhibits a three-dimensional spiral structure, and in the conjugate fiber of the present invention, each single yarn constituting the conjugate fiber has a spiral crimp. In addition, the composite fibers composed of these single yarns also exhibit spiral crimps.

  And the composite fiber of this invention can obtain the fabric excellent in stretch-back property by having an actual crimp and expressing a latent crimp. In addition, being excellent in stretch-back property means that the recovery speed when instantaneously returning to the original dimension immediately after releasing the stress after applying the stress to the fabric and stretching is high.

The actual crimp rate (C0) in the present invention is 0 <C0 ≦ 5, and preferably 0.5 ≦ C0 ≦ 5. Here, the actual crimp rate (C0) is calculated by the following equation. L1 is obtained by applying a tension of 90.91 × 10 ⁻³ cN / dtex to the fiber and applying 1.67 × 10 ⁻⁴ cN to the heel. The length measured after standing for 30 minutes after applying a load of / dtex, L0 was measured after changing the load from 1.67 × 10 ⁻⁴ cN / dtex to 90.91 × 10 ⁻³ cN / dtex after measuring L1 He is a chief.
C0 (%) = [(L0−L1) / L0] × 100

  When the actual crimp rate (C0) exceeds 5, particularly in the case of a woven or knitted fabric obtained by using only the conjugate fiber of the present invention (use of 100%), there are many wrinkle standing defects and poor surface smoothness. . In addition, since it exhibits a spiral-like crimp, thread breakage is likely to occur when processing or weaving or weaving composite fibers, resulting in poor process passability. On the other hand, if the actual crimping ratio is less than 0.5, the resulting fabric has poor stretch-back properties.

Furthermore, the conjugate fiber of the present invention has latent crimping performance, and the latent crimp rate (C100) is 30 ≦ C100 ≦ 60, and it is particularly preferable that 35 ≦ C100 ≦ 58. Here, the scattered crimp rate (C100) is calculated by the following equation. A1 is obtained by applying a tension of 90.91 × 10 ⁻³ cN / dtex to the fiber and applying 1.67 × 10 ⁻⁴ cN to the heel. This is the length measured after boiling water treatment for 30 minutes while applying a load of / dtex and then applying a load of 1.76 × 10 ^-3 cN / dtex and leaving it for 30 minutes. A0 is 1.76 × 10枷 Length measured after changing from ^-3 cN / dtex to 4.4 × 10 ^-2 cN / dtex.
C100 (%) = [(A0−A1) / A0) × 100

  By setting the latent crimp rate (C100) to 30 or more, even when combined with other materials or subjected to various processing, it is made into a woven or knitted fabric and has excellent stretch back performance by heat treatment or the like. It becomes possible to make a fabric. Therefore, if the latent crimp rate is less than 30, a fabric having sufficient stretch back performance cannot be obtained. On the other hand, when the actual crimp rate exceeds 60, particularly in the case of a woven or knitted fabric obtained by using only the composite fiber of the present invention (use of 100%), there are many wrinkle-protruding defects and the surface smoothness is poor.

  In order to adjust the apparent crimp rate and the latent crimp rate of the composite fiber of the present invention, the intrinsic viscosity and intrinsic viscosity difference, copolymer component, single yarn fineness, and residual elongation of high-viscosity polyester and low-viscosity polyester are appropriately selected. It can be adjusted by doing.

  The residual elongation is preferably 15 to 40%. If the residual elongation exceeds 40%, the latent crimp rate is lowered, and the resulting fabric tends to have poor stretch-back properties. On the other hand, if the residual elongation is less than 15%, the operability is liable to deteriorate, for example, cutting of a single yarn occurs during stretching.

  Next, the manufacturing method of the composite fiber of this invention is demonstrated. The conjugate fiber of the present invention can be produced by a usual conjugate spinning type melt spinning machine. First, two kinds of polyester components are merged on the back surface of the spinneret so as to be a side-by-side type or an eccentric core-sheath type, and are discharged from the same spinning hole and spun. In this case, the spinning temperature is appropriately selected depending on the intrinsic viscosity of the polyester component, but is usually preferably in the range of 280 ° C to 310 ° C. The spun yarn is cooled and solidified, then applied with a spinning oil agent, taken up at a speed of 1000 to 4000 m / min, taken up once, and then subjected to heat drawing by a drawing machine in a separate process, or taken up yarn The composite fiber of the present invention can be obtained by hot drawing continuously after spinning without stripping the strip once. The draw ratio in the above production method is appropriately selected according to the residual elongation of the fiber at the time of drawing, and is preferably selected so that the residual elongation after drawing is in the range of 15 to 40%.

  And although the composite fiber of this invention can be used as a warp and a weft as it is, you may mix and use with other yarn. Moreover, false twist processing may be given and false twist mixing fiber may be sufficient. Moreover, a real twist may be given, a real twist mixed fiber may be sufficient, and what combined these may be sufficient.

  Since the latent crimp of the conjugate fiber of the present invention is expressed by crimping by heat treatment, the conjugate fiber of the present invention is made into a fabric by knitting or weaving in consideration of workability such as process passability. Thereafter, it is preferable to perform boiling water treatment to develop latent crimps. In particular, it is preferable to perform boiling water treatment in the dyeing step to develop it.

Hereinafter, the present invention will be described more specifically with reference to examples. In the examples, various values were measured and evaluated as follows.
(1) Intrinsic viscosity It was measured by the method described above.
(2) Fabric Texture The obtained composite fiber was subjected to 1500 T / M twist (S twist, twist coefficient K11000), and then vacuum heat set was performed at 80 ° C. for 40 minutes. Weaving a plain weave fabric with a warp density of 110 / 2.54cm and a weft density of 80 / 2.54cm using this yarn as warp and weft, scouring, treating in boiling water at 100 ° C for 30 minutes, and then air drying A woven fabric was obtained.
This fabric was evaluated by touch by 10 panelists. Each of stretch back, surface smoothness (smoothness without wrinkles), and soft feeling was evaluated on a scale of 1 to 10 (10 was the best), and the average score of 10 people It showed in.

Examples 1 to 3 and Comparative Examples 1 to 5
As a high viscosity polyester component (POH), 2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane (BP-A / EO), isophthalic acid (IPA), 5-sodium sulfoisophthalic acid (SIP) ) Content (copolymerization amount) is a copolymerized PET having the value shown in Table 1, and the intrinsic viscosity is the value shown in Table 1. As the low viscosity polyester component (POL), PET having the intrinsic viscosity shown in Table 1 was used.
Equal amounts of both polyester components were fed to a compound spinning type melt extruder, melted at a spinning temperature of 295 ° C., both components were merged at the back of a spinneret having a spinning hole, joined to a side-by-side mold, and spun. After spinning and solidifying the spun yarn, the yarn was converged while applying an oil agent, and was taken up with a take-up machine through a take-up roller having a surface speed of 3000 m / min.
Next, the obtained fiber was supplied to a drawing machine, drawn at a draw ratio of 1.6 times through a roller having a surface temperature of 85 ° C. and a hot plate having a temperature of 170 ° C., and wound up.
The obtained conjugate fiber exhibited a cross-sectional shape of the bonded surface shown in FIG. 1 (B), and each filament configuration was as shown in Table 1.

  Table 1 shows the evaluation results of the apparent crimp rate (C0), latent crimp rate (C100) and fabric texture of the obtained composite fiber.

As is clear from Table 1, the composite fibers of Examples 1 to 3 all satisfy the scope of the present invention in terms of the actual crimp rate and the latent crimp rate, and the obtained fabric has surface smoothness, Stretchback and softness were both excellent.

On the other hand, the composite fiber of Comparative Example 1 was too large in both the actual crimp rate and the latent crimp rate, and the composite fiber of Comparative Example 2 was too large in the apparent crimp rate. Although it was good, the texture was conspicuous and the surface smoothness was poor, and the softness was also inferior. Since the conjugate fiber of Comparative Example 3 had a too low latent crimp rate, the obtained fabric was inferior in stretch back property. Since the conjugate fiber of Comparative Example 4 had a too large latent crimp rate, the resulting fabric was conspicuous in texture and poor in surface smoothness. Since the conjugate fiber of Comparative Example 5 does not contain 2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane as the high-viscosity polyester component, the latent crimp rate is slightly inferior. .

It is a cross-sectional schematic diagram of the single fiber which shows one embodiment (side-by-side type) of the composite shape of the composite fiber of this invention. It is a cross-sectional schematic diagram of the single fiber which shows the other embodiment (eccentric core-sheath type) of the composite shape of the composite fiber of this invention.

Claims (1)

2,2-bis {4- (Β-hydroxyethoxy) phenyl} propane and a sulfonate group compound or isophthalic acid component in a total amount of 5 to 20 mol%, a high viscosity polyester component and ethylene terephthalate as a main repeating unit This is a composite fiber with a single yarn fineness of 0.5 to 4.0 dtex , which has a single yarn shape in which the viscosity polyester components are bonded to each other in a side-by-side type or an eccentric core-sheath type, and has a spiral-like manifest crimp. A stretchable polyester composite fiber characterized in that the actual crimp rate (C0) and the latent crimp rate (C100) satisfy the following values simultaneously.
0 <C0 ≦ 5
30 ≦ C100 ≦ 60
The actual crimp rate: C0 (%) = [(L0−L1) / L0] × 100
Potential crimp rate: C100 (%) = [(A0−A1) / A0) × 100
L1: The length of the lash measured after the fiber was pulled while applying a tension of 90.91 × 10 ^-3 cN / dtex and the load was applied to the heel with a load of 1.67 × 10 ^-4 cN / dtex for 30 minutes. L0: After measuring L1,枷 Length A1 measured by replacing the load from 1.67 × 10 ^-4 cN / dtex to 90.91 × 10 ^-3 cN / dtex: Remove the fiber while applying a tension of 90.91 × 10 ^-3 cN / dtex,枷 Length measured after boiling water treatment for 30 minutes while applying a load of × 10 ^-4 cN / dtex, after applying a load of 1.76 × 10 ^-3 cN / dtex and left to stand for 30 minutes A0: After measuring A1, the load is 1.76 ×枷 Length measured from 10 ^-3 cN / dtex to 4.4 × 10 ^-2 cN / dtex