JPS6141323A - Hollow composite yarn - Google Patents

Abstract

PURPOSE:To produce a crimped elastic fiber having the elasticity originated from fine crimps and the elasticity of the elastomer, by joining a thermoplastic elastomer with a polyamide or a polyester in a specific composite state. CONSTITUTION:The titled yarn is a side-by-side or an eccentric sheath-core hollow composite yarn composed of a thermoplastic elastomer E and a polyamide or a polyester P, satisfying the formulas 4>=b/a>=1.2, 3.0>=(E+S)/P>=0.50, ESiPi>= a/2 and 0.40>=S/(E+S)>=0.06 wherein (a) is the length of the minor axis passing through the centroid of the cross-section of the fiber, (b) is the length of the major axis passing through the centroid of the cross-section of the fiber, E is the area of the elastomer component E, S is the area of the hollow part S enclosed with the elastomer component E, P is the area of the polyamide or polyester component P, and ESiPi is the distance between the centroid Ei of the elastomer including the hollow part and the centroid Pi of the polyamide or polyester component.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is a composite fiber of a thermoplastic elastomer and polyamide or polyester, and by adjusting the composite state of the fiber, the elasticity due to fine crimping and the elasticity of the elastomer itself can be improved. This invention relates to composite fibers that can be used in combination with elasticity.

[Prior Art] It is well known that composite fibers made by laminating polymers with different heat shrinkability in a side-by-side type or an eccentric sheath core type have latent crimp ability. Among these composite fibers, one component is urethane elastomer,
Composite fiber using polyamide as the other component (Special Publication 55
36725, Japanese Patent Publication No. 55-27175) has many fine crimps and excellent crimp performance, and is therefore used in fields that require crimp elasticity, such as pantyhose.

However, although the composite lIi navy blue using these polyurethane 1 elastomers is effective in producing fine crimp by utilizing the heat shrinkability of the polyurethane elastomer, the elasticity (rubber elasticity) properties of the polyurethane elastomer itself are Almost never used.

On the other hand, 100% polyurethane elastic thread has only rubber elasticity and its elongation reaches 400-500%, making it difficult to use as is.As a way to suppress its elongation to 200-300%, it is wound on urethane elastic thread. A so-called covering yarn is used, which is a single or double wrap of a compressed yarn or a flat yarn. However, the urethane yarns used in such covering yarns are obtained by wet spinning or dry spinning, and are inferior in productivity compared to melt spinning. Since the covering process is added, the cost l- is high, and the actual situation is that it is only used for special purposes.

Furthermore, such covered yarns also have the disadvantage of lacking the high properties of crimped yarns.

OBJECT OF THE INVENTION 1 The object of the present invention is to obtain high strength and elastic properties by crimping, as well as elastomer (
The object of the present invention is to provide at a low cost a crimped elastic fiber that also has rubber elastic properties unique to mer.

[Structure of the Invention J According to the present invention, there is provided a side-by-side type or eccentric sheath core type hollow conjugate fiber comprising a thermoplastic elastomer and polyamide or polyester, each of which has the following components [I]
It is a hollow composite Il fiber characterized by being composited so as to satisfy the formula ~ [rV].

4≧b/a ≧1.2 ・・−・・−
[I] 3.0≧ (E+S)/P≧ 0.50
・・・・・・[ff] ESi Pi ≧a/2
=・River[1[]]040≧S/(E-1-8)≧
0.06... [rV] The thermoplastic elastomer used as one component in the present invention is an elastomer that can be melt-spun, and usually has a melting point of 200°C to 2.0°C.
A material having a hardness of 90 to 100 at 40°C is used. Examples of the thermoplastic elastomer include polyurethane elastomers and polyamide elastomers. As the polyurethane elastomer, polyester having a hydroxyl group at the end and/or a molecular weight of 1000 to 30 is used.
00 poly(oxyalkylene) glycol, a diisocyanate, a glycol chain extender, and optionally a polycarbonate having a terminal hydroxyl group are further added and reacted to produce a thermoplastic polyurethane. Examples of polyester include dibasic acids such as adipic acid and monobasic acid and diols such as ethylene glycol, butylene glycol, and diethylene glycol. Examples of poly(oxyalkylene) glycol include poly(oxyalkylene) glycol and poly(oxypropylene). ) Glycol, block copolymers and homopolymers such as poly(oxybutylene) glycol are used. As the diisocyanate, 2,4-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, etc. are selected. As the chain extender, ethylene glycol, propylene glycol, butylene glycol, and 1,4-β-hydroxyethoxybenzene can be used. Further, the optionally used polycarbonate must be one polymerized from bisphenol A and phosgene or hisphenol 8 and diphenyl carbonate, and must have a terminal hydroxyl group.

In addition, polyamide elastomers include polylauryl latatum and polybutylene glycol (1,4 butane diA).
Copolymers of dicarboxylic acids (formed from -ols) are common. The hardness can be varied in various ways by changing the molecular weight of butylene glycol, which is the rubber component, and can also be changed by changing the copolymerization ratio of polylauryl latatum and the rubber component.

Further, as the thermoplastic polymer which is the other component, polyester polyamide is preferably used. As the polyester, polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, etc., and those obtained by copolymerizing these with 5-sodium sulfoisophthalate are more preferably used. In addition, examples of polyamide include nylon-6, nylon 66, nylon 6°10, nylon 11. Nylon 12. nylon 13
etc. can be used. It is necessary to select a combination of these two components that has good compatibility and lamination adhesion so that the components do not peel off during spinning, stretching, processing, and fabric manufacturing plants. In particular, when polyester is used as one component, it is preferable to use a polyester elastomer, such as a block copolymer of polyether and polyester, as the thermoplastic elastomer. Further, it is desirable to use polyethylene terephthalate copolymerized with 5-sodium sulfoisophthalate as the polyester component, since this improves the bonding adhesiveness. When polyamide is used as one component, it is preferable to use caprolactone-based or polycarbonate-based polyurethane or polyamide-based elastomer, such as a copolymer of polylauryl latatum and polyol, as the thermoplastic elastomer.

In order to improve light resistance, a light resistance improver such as a benzophenone compound, a benzotriazole compound, or an inorganic manganese compound may be added to these elastomers and polyamides.

A feature of the present invention is that the above-mentioned thermoplastic elastomer and polyamide or polyester are bonded together in a specific composite state in the cross section of the composite fiber.

Fig. 1 is a cross-sectional view showing an example of the hollow composite fiber of the present invention, where i is the center of gravity of the fiber cross section, a is the length of the minor axis passing through the center of gravity i of the fiber cross section, and b is the length of the short axis passing through the center of gravity i of the fiber cross section. The length of the major axis passing through the center of gravity i of the fiber cross section, E is the area of the elastomer component in the fiber cross section, S is the area of the hollow part surrounded by the elastomer component in the fiber cross section, P is the polyamide portion in the fiber cross section or the area of the polyester component, Ei is the center of gravity of the elastomer component in the i-plane of the fiber Yokota ESi is the center of gravity of the elastomer component and the hollow portion Pi is the center of gravity of the polyamide or polyester component in the tJA miscellaneous cross section.

In the present invention, first, the relationship between a and b is 4≧b/a≧1
．． It is necessary to satisfy the following equation.

If b/a is greater than 4, the cross-sectional shape of the fibers becomes excessively flattened, resulting in a rough feel and poor texture when made into woven or knitted fabrics. The diameter of the crimped coil becomes large and fine crimps cannot be obtained, resulting in crimp #AML.
The elastic properties of the material deteriorate. On the other hand, when b/a is smaller than 1.2, the elastic properties of the crimped fibers improve, but the crimped fibers no longer take the screw structure described later, and the rubber elasticity of the elastomer component cannot be utilized. It disappears.

Furthermore, in the present invention, it is necessary that the relationship between E -1-S and P satisfy the expression 3.0≧E+S/P≧0.50. When E+S/P is greater than 3.0, the elastomer component becomes too large and crimp I! physical properties such as color fastness, strength, and elongation modulus of
When made into a single knitted fabric, it becomes unusable. Also, E+
When S/P is less than 0.50, rubber elasticity is almost lost, and it becomes impossible to obtain a crimped fiber having both crimped elasticity and rubber elasticity, which is the object of the present invention.

The value of E+S/P is most preferably in the range of 0.67 to 2.0, and is usually set to 1.

Next, in the present invention, the length of the straight line connecting ESi and Pi is Es1
It is necessary that p+ is 4/2 or more. This is E
i and pi are in the major axis direction, and the distance between their centers of gravity Est
pt is more human than a/2, which means that the cross-sectional shape is cocoon-shaped or rectangular as shown in FIG. 1, and the center of gravity of the same component is located in the long axis direction. Composite fibers having a circular cross-sectional shape as shown in FIG. 2A are not included in the scope of the present invention. If Ei'pi is smaller than a/2, even if sufficient crimp development occurs, the screw structure described below cannot be achieved sufficiently, resulting in a mere three-dimensional spiral crimped fiber with IIA miscellaneous characteristics. Only the characteristics can be used, and the rubber elasticity of the elastomer component cannot be used.

It is preferable that the centers of gravity Ei and Pi of the same component are both on the major axis passing through i, and even if [i and pi are slightly deviated from the major axis, Ei l! : Line i Ei connecting i.

Alternatively, it is desirable that the angle formed by the line iPi connecting Pi and i and the short axis passing through i is within the range of 906±30@.

Furthermore, in the present invention, it is necessary that S/E+Sh<o be larger than 06 and smaller than 0.40. S/E
If +S is less than 0.06, there is no effect of reducing the use of expensive elastomers, which is one of the objects of the present invention, to provide an inexpensive composite.

If S'/E + S is thicker than 0.40, it will not impede the purpose of the present invention, but rather it will be restricted by the silk spinning technology, and if you try to make it thicker than 0.40, it will cause hollow parts. If the hollow part is not formed or the hollow part is crushed, quality problems will occur.The most preferable range of S/E+8 is 0.10 to 0.30. There is a concern that if the amount of elastomer used is reduced by increasing the cross-sectional area, the crimp performance, which is the main purpose of composite! Not only is the crimp performance not much different from that of a solid type, but by providing the hollow part closer to the joint surface of the elastomer and polyamide or polyester, it is easier to form the single screw structure described below, making use of rubber elasticity. It was found that the quality improved.

Further, by providing a hollow portion as in the present invention, not only can the amount of elastomer used be reduced, but also the ratio P/E of one component of one lastomer to the polyamide or polyester component can be increased in order to obtain the same crimp performance. This also has the advantage that the strength of the composite fiber can be increased because the proportion of polyamide or polyester having excellent mechanical properties is high when comparing the same fineness.

In the present invention, the term "hollow part surrounded by an elastomer" means that 2/3 or more of the cross-sectional area of the hollow part exists on the elastomer side from the joint surface of the elastomer and polyamide or polyester. (Therefore, the remaining ⅓ or less may be surrounded by the polyamide or polyester component.) Furthermore, the number of hollow parts is not limited to one.

The hollow composite fiber of the present invention is obtained by composite melt spinning of thermoplastic elastomer and polyamide or polyester, but since the melt viscoelastic properties of the composite fibers differ for the same components, it is necessary to use a spinneret suitable for this. It is.

The most effective method for this is to separately discharge polymers of the same composition from a die as shown in FIG. 4 and combine them at a position within 2 spaces from the die surface.

The elastomer component E @ is led to the inlet A and discharged from the discharge port Ea, and the other polyamide or polyester P is led to the supply port B and discharged from the discharge port PB, 2 m from the mouth surface.
It can be easily obtained by joining the E component and the P component at a certain point within the range.

At this time, in order to satisfy the condition of 23≧E/P≧0.43, the discharge ports of the E component and P component must be separately set up to meet this condition using a gear pump (not shown). Just adjust it. The area of the discharge DEa and Pb should be designed according to each discharge, but as a rough guide, the linear velocity when passing through the discharge port should be 5'rrL/min to 13
It is sufficient if the speed falls within the range of m/min. Then 4≧b/a≧
It is necessary to satisfy the condition 1.2, which is preferably adjusted by the distance 1 between Ea and Pb and the angle θ between their discharge ports as shown in FIG. 4A. Increase the base, θ
If you reduce b/a, b/a will increase, and conversely, if you reduce polishing, θ
If b/a is increased, b/a becomes smaller. However, in order to satisfy the conditions of the present invention, the polishing should be between 0.3 and 0.1 am;
θ is fully adjustable within the range of 6° to 30°. In order to satisfy the following condition, Es1pi≧a/2,
Although it depends on the other two conditions, if the discharge ports of Ea and Pb are circular, Es+ p+ will increase if the capacitance is increased in the same way as changing the conditions of b/a, and θ
If ESi Pi is made smaller, ESi Pi becomes larger. However, E
This is also possible by changing the shape of the discharge ports of a and Eb. If Ea and Pb are made triangular and arranged with a distance of p as shown in Figure 4, ESi can be made better than when Ea and Pb are circular. Pi becomes large.

Furthermore, to adjust the size of the hollow part of the elastomer, Ea
The slit width (X), the slit length (y), and the slit interval (Z) are used. That is, the hollow portion can be made larger by making the slit width X smaller and the slit length V larger (and by changing the slit interval Z by a relatively large amount).

Furthermore, in order to obtain an eccentric sheathed core type composite fiber, the elastomer component E is introduced into the inlet C using a die as shown in Fig. 5A.
The polyamide or polyester P guided through the inlet port is made into a sheathed core shape in the inlet port A, and then the discharge port L
It is obtained by discharging it into a hollow sheathed core shape through ea and joining it with polyamide or polyester discharged from discharge port PB. The shape of the discharge port is 5th.
No example is shown in the illustration.

It is also effective to use this die for composite spinning into an eccentric sheathed core type. By locating the elastomer component in the core, this method is highly effective in overcoming the drawback that the ex-1-mer component sticks during winding, making it difficult to separate into single fibers.

[Function of the invention] In order to explain the screw structure, FIG.
FIG.

First, when a hollow composite #A strip consisting of a thermoplastic elastomer component E and a polyamide or polyester component P that satisfies the requirements of the present invention is stretched and heat-shrinked, a spiral three-dimensional talinbu appears as shown in A. The E component is located inside and the P component is located outside.

When this is stretched, the E component is stretched straight as shown in the picture, but the 1) component is wrapped around the outside of the E component at a certain angle like the threads of a wood screw, that is, it has a screw structure. Become. This structure is created because the center of gravity Ei of the elastomer component is located far away from the center of gravity i of the fiber cross section in the long axis direction, and the center of gravity Ei of the elastomer component is far away from the center of gravity i of the fiber cross section in the long axis direction.
This is due to the ability to contract more greatly.

In order to obtain such a screw YlA structure, 4≧b/a
It is necessary to satisfy the following requirements: ≧1.2 and ESI Pi≧a/2. The center of gravity Ei of the elastomer component approaches the center of gravity i of the fiber cross section, b/a<1.2, ESi P
If i < a /2, the point of contraction of one component E of one lastomer will be too close to the center of gravity i of the cross section of the fiber, and contraction sufficient to achieve this screw structure will not be allowed. In order to manufacture such a screw structure more efficiently, as shown in the opening of Figure 2, the bonding surface between the elastomer component E and the polyamide or polyester component P is small, and the center of gravity Ei of the elastomer component is the polyamide or polyester component. It will be easily understood that it is more preferable to be away from the center of gravity Pi of the fiber or the center of gravity i of the fiber cross section. However, when forming the shape as shown in Figure 2, making the bonding surface between the elastomer and polyamide or polyester extremely small may cause excessive adhesion of oil applied during spinning or drawing to the recesses, adhesion of dirt, and unfavorable light reflection. By providing the hollow part closer to the joint surface, as shown in the opening in Figure 1, which is an example of the present invention, the defects caused by the shape of the opening in Figure 2 are eliminated. However, there is an advantage that the same effect can be obtained by reducing the joint surface length a.

If the screw-structured fiber l1l (portion in Figure 3) is further stretched, it can be stretched to the shape shown in Figure 3.

Therefore, the process of changing from the shape shown in FIG.

The great effect of the present invention is that this rubber elasticity can be imparted even though it is a composite fiber, and that it can be provided at a low cost.
Conventional simple side-by-side type or eccentric sheath core type composite fibers cannot utilize this rubber elasticity. As can be easily understood, this rubber elasticity has good elongation recovery properties, and the elongation elastic force is also greater than the crimp elasticity, so that when used for pantyhose etc., good fitting properties can be obtained.

From the above, it can be easily understood that the composite fiber of the present invention can utilize both crimped elasticity and rubber elasticity, and that the manufacturing cost can be greatly reduced. On the other hand, conventionally known conjugate fibers having a cross-sectional shape as shown in FIG. 2A are elongated and deformed in the order shown in FIG. The fibers subjected to the drawing and crimp treatment exhibit a spiral three-dimensional crimp in which the E component is located on the inside and the P component is located on the outside, similar to the case shown in FIG. 3A. (Fig. 3) When this is further stretched, it suddenly takes on the form shown in Fig. 3 (E) without taking on the screw structure (Fig. 3) shown by the composite fiber of the present invention. Therefore, the crimp elasticity in the process of changing from the opening in Figure 3 to the configuration in Figure 3 E can only be used, and in the process of further elongating from Figure 3 E to the configuration in Figure 3, the screw structure Therefore, the rubber elasticity cannot be used.

In addition, in the crimped form and screw structure shown in Fig. 3, there is an inversion part of the P component as partially shown in Fig. 3, but this is not a particular obstacle in use. No.

As explained above, the hollow composite fiber of the present invention is composed of a thermoplastic elastomer component and a polyamide or polyester component in a special arrangement (using the characteristics of both crimp elasticity and rubber elasticity). As a result, it is possible to obtain an excellent crimped composite Ifi1d1 with unprecedented elastic recovery and elastic strength at high elongation, making it extremely useful for pantyhose and slouch woven and knitted fabrics, as well as elastomer. By having a hollow portion surrounded by , it is possible to reduce the amount of expensive elastomer components used, so that a high-performance composite yarn can be provided at a low cost.The present invention will be explained below with reference to Examples.

Example: Nylon 6 (intrinsic viscosity [η] = 1.1>) and commercially available thermoplastic polyurethane Elastran E595 (Capro type) (Nippon Elastran KK) as the elastomer component.
(manufactured by A. Co., Ltd.) were separately melted at 247° C. and 228° C., and composite spinning was performed using a side-by-side type nozzle shown in FIG. 4A, which was heated to 240° C. Elastomer and GiI+ in the cross section of composite fiber? =: <'s face ``/
p is changed by the discharge ratio of the imaginary pore pump, and
b/a and Ei pi are Ea of the cap, not shown in Figure 4 A.
, pb.

The changes were made by variously changing the sentence and θ.

The area ratio S/E+S of the hollow portion was varied by variously changing the slit width x 1 slit length y and the slit interval Z.

The winding speed was 500 m/min, and 0.6% of silicone oil was applied, and the yarn was wound up as an undrawn yarn, and then stretched in a separate step so that the elongation at break was 30% to 40%. The produced yarn was evaluated by placing the drawn yarn in a skein, applying a load of 2 mg/de, crimping in clear water for 20 minutes, and then 1
The crimped yarn was air-dried under the weight of grapes day and night, and then the crimped yarn was placed in a Tensilon type tensile tester and evaluated while observing the medium and long parts of the material with a 20x magnification casetometer. The conditions at this time were: material length 20 cm, initial load 2#15F/de, and extension speed 10.
0%/min, chart speed 20 cm, 1 min, and the cassette meter was focused on the central part 10aR of the sample and started. When observing, the state shown in Figure 3A is seen at the start, and as it is stretched, the crimp becomes longer and eventually becomes the state of the mouth. Mark the place corresponding to the elongation at this time. The degree of elongation up to this point is the crimp elongation rate, and if it is further elongated, it will eventually become crimp. The elongation from this opening to C is the rubber elastic modulus. The measurement is the average value of 5 times.

In addition, as a comparative example, N in Table 1 was obtained by spinning as shown in FIG. 2A using a normal side-by-side type spinneret.

1, and furthermore, the screw structure has an indicated size of Nα2 to 9 in Table 1 for the conventional type that does not have a hollow part surrounded by the lastomer.
It was shown to.

(The following is a blank space) As is clear from the examples, the material of the present invention has excellent crimp performance, rubber elasticity performance, and mechanical properties, and can reduce the amount of expensive elastomer components.

For example, the comparative example NQ 3 and the present invention No. 10.1
Comparing No. 1°12, No. 10.11.12 is superior to No. 3 in both crimp performance and rubber elasticity performance. Furthermore, in order to obtain the same crimp performance and rubber elasticity performance, for example, compare Nα3, which is a comparative example, with No. 14, 15, and 16 of the present invention.

14, 15, and 16 have crimping performance and rubber elasticity comparable to No. 3 despite having 20% less elastomer component, and are superior in strength, so they do not cause yarn breakage when used in woven or knitted fabrics. This is effective in solving the problem, and can also reduce the cost of elastomer by 20% compared to No. 3.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of the hollow conjugate fiber of the present invention, in which E indicates the hollow portion of the elastomer S, and P indicates the polyamide or polyester. Figure 2 is a circular composite fiber that cannot utilize the rubber elasticity of Ex 1 to 1, and the mouth is made of elastomer. It is a composite fiber that uses a large amount of elastomer, although its rubber elasticity can be utilized. FIG. 3 is a model diagram of the crimp in an extended state to explain the screw structure. FIG. 4 and FIG. 5 are cross-sectional views showing an example of a die used for manufacturing the hollow composite fiber of the present invention. Figure 1 zFjA Figure 3 (a) (b)
(/X) Figure 4 (a) (b), a, Figure 5

Claims (1)

[Scope of Claims] (1) A hollow conjugate fiber having a flat cross section, comprising a thermoplastic elastomer and a polyamide or polyester component, each component satisfying the following formulas [I] to [IV]. Hollow composite fiber characterized by being composite 4≧b/a≧1.2...[I] 3.0≧(E+S)/P≧0.50...[ II]
ESiPi≧a/2...[III] 0.40≧S/(E+S)≧0.06...[I
V] However, a is the length of the minor axis passing through the center of gravity of the fiber cross section, b is the length of the major axis passing through the center of gravity of the fiber cross section, E is the area S of the elastomer component occupying the fiber cross section. The area P of the hollow part surrounded by the elastomer component is the area of the polyamide or polyester component in the cross section of the fiber ESiPi is the center of gravity Ei of the combined elastomer and hollow part in the cross section of the fiber, and the center of gravity Pi of the polyamide or polyester component Indicates the distance between