JPH10266011A - Spinneret plate for spinning core-sheath conjugated fiber and spinneret device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spinneret for core-sheath conjugated fibers capable of eliminating the discharge unevenness of a core component polymer when forming the core component polymer having a low melt viscosity and a sheath component polymer having a high melt viscosity into the core-sheath conjugated fibers and suppressing a reaction in a contact interface of the mutual molten polymers in a core-sheath conjugated stream in the interior of the spinneret plate when using the polymer having high reactivity as the core component, further providing core-sheath conjugated hollow fibers having a hollow part in the interface between the core and sheath of the core- sheath conjugated fibers and producing the core-sheath conjugated fibers without causing the cracking of the hollow with good operating efficiency. SOLUTION: This spinneret plate for core-sheath conjugated fibers is obtained by arranging a sheath component polymer passage 14, a core component polymer passage 13 independent of the sheath component polymer passage 14, sheath component polymer discharge holes 8 comprising slits arranged in an annular or a polygonal shape as the discharge holes and a core component polymer discharge hole 7 independent of the sheath component polymer discharge holes 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spinneret for spinning a core-sheath conjugate fiber, and more particularly, to a core in which a core component polymer having a low melt viscosity and a sheath component polymer having a high melt viscosity are used as a core-sheath composite fiber. A base plate that eliminates uneven discharge of component polymers and can suppress the reaction at the contact interface between molten polymers in the core-sheath composite flow inside the base plate when a highly reactive polymer is used as the core component. TECHNICAL FIELD The present invention relates to a die plate capable of providing a core-sheath composite hollow fiber having a hollow portion at a core-sheath interface of the composite fiber, and to a die plate capable of obtaining a core-sheath composite hollow fiber free of hollow cracks with good operability.

[0002]

2. Description of the Related Art Various spinnerets for producing core-sheath composite fibers and core-sheath composite hollow fibers have been proposed.
007 and JP-A-63-256708, a pipe through which a core component polymer flows is inserted into a distribution plate in which distribution holes corresponding to spinning holes of a die plate are perforated, and the shape of the distribution plate is defined. There has been proposed a spinneret for obtaining a homogeneous core-sheath composite fiber with little eccentricity. In this spinneret, since a pipe is inserted into the distribution plate, a core-sheath composite flow is formed inside the spinning hole of the die plate. When the core component polymer is easily introduced into the discharge hole due to the pressure difference between the core component polymer and the sheath component polymer, uneven discharge tends to occur in the length direction. There was a problem that transesterification and the like proceeded at the contact interface between the molten polymers in the core-sheath composite flow inside the hole.

In a spinneret for a core-sheath porous hollow composite fiber, Japanese Patent Laid-Open Publication No. 7-292515 discloses a spinneret plate having a slit-type orifice, in which an orifice is annularly formed through two or more discontinuous portions. A core-sheath composite porous hollow fiber base plate comprising a plurality of arranged outer slits and a connecting slit protruding from the center of the inner edge length of each outer slit toward the center of the orifice and a central slit communicating with each connecting slit. A proposal has been made. Since this die plate has a connecting slit communicating with the outer peripheral slit and the center hole, the discontinuous portion between the outer peripheral slit and the center hole is supported only at one discontinuous portion of the outer peripheral slit, and high viscosity is achieved. There is a problem that the die plate is easily distorted due to pressure and repeated fatigue caused by the polymer, and satisfactory operability of the core-sheath composite hollow fiber has not been achieved.

Japanese Patent Laid-Open No. 4-65507 discloses that
There has been proposed a spinneret device for obtaining a fiber having a hollow portion at the center of a composite fiber laminated in three layers. In this spinneret, each component is supplied from an individual inlet, and after the two side components are merged with the middle component at the inlet of the undiluted solution of the spinneret, a spinning hole composed of a plurality of arc slits is formed as a composite polymer. It is discharged from. In this case, the polymer discharged from the arc slit at the same time as being discharged from the arc slit in a state in which the three component polymers are compounded causes a phenomenon (kneeling phenomenon) in which the polymer is refracted toward the outer periphery of the arc slit. There is a problem that joining becomes difficult and hollow cracks occur.

Further, in Japanese Unexamined Patent Publication No. Sho 59-192721, hollow cracks occur even if the melt viscosity difference between the core component polymer and the sheath component polymer is large even if the shape of the arc slit is devised. There was a problem that the fibers became fibers and the operability was reduced.

In Japanese Patent Application Laid-Open No. 57-56512, when a core component having a low melt viscosity and a sheath component polymer having a high melt viscosity are introduced into a discharge hole as a core-sheath composite flow, the core component polymer is introduced into an arc slit. As in the previous case, a kneading phenomenon occurs in the entering arc slit, resulting in a fiber having hollow cracks, and there is a problem that the operability is reduced.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to produce a core-sheath composite fiber and a core-sheath composite hollow structural fiber which cannot be achieved by a conventional core-sheath composite die device or a die device for a core-sheath composite hollow fiber. In detail, core-sheath conjugate fiber using a special core component polymer with low melt viscosity and high reactivity,
Manufactures core-sheath composite hollow fibers with good operability even when the melt viscosity of the core component polymer is lower than the melt viscosity of the sheath component polymer or when the melt viscosity difference between the core component and the sheath component polymer is large. The present invention provides a spinneret for a core-in-sheath composite fiber for performing the above.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a die plate having a sheath component polymer flow path and a core component polymer flow path independent of the sheath component polymer flow path, and having an annular discharge port. Alternatively, a core-sheath composite fiber spinning die plate (hereinafter referred to as a spinneret) having a sheath component polymer discharge hole formed of slits arranged in a polygonal shape and a core component polymer discharge hole independent of the sheath component polymer discharge hole. (Referred to as a base plate).

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. FIG. 1 is a longitudinal sectional view showing an example of a core-sheath composite fiber spinneret of the present invention. FIG. 2 is an upper drawing of a die plate showing an example of an independent introduction hole of the core-sheath component polymer in the upper part of the die plate. FIG. 3 is a vertical cross-sectional view of a base plate showing an example of an independent core-sheath component polymer flow path in the base plate. FIG. 4 is a bottom view of the base plate showing an example of a sheath component polymer discharge hole formed of a slit formed in the base plate and a core component polymer discharge hole independent of the sheath component discharge hole.

1 to 4, reference numeral 1 denotes an upper introduction plate, 2 denotes a lower introduction plate, 3 denotes a base plate, and 4 denotes a core component polymer introduction hole formed in the upper portion of the base plate 3. One or a plurality of sheath component polymer introduction holes 5 are formed around the periphery 4 on the same track. Reference numeral 6 denotes a discharge hole formed in the lower portion of the base plate 3, and is composed of a core component polymer discharge hole 7 and a sheath component polymer slit discharge hole 8 formed around the core component polymer discharge hole.

The core component polymer A is supplied from the supply hole 9 of the upper introduction plate 1 and is introduced from the supply hole 11 of the lower introduction plate 2 to the introduction hole 4 above the mouthpiece plate 3 and flows therethrough. It is discharged from the core component polymer discharge hole 7 below the base plate 3 through the passage 13.

On the other hand, the polymer B of the sheath component is
Supply port 12 of the lower introduction plate 2
It is introduced into the sheath component polymer introduction hole 5 above the base plate 3,
After passing through the sheath component polymer flow path 14 of the base plate 3, the base plate 3
It is discharged from the lower sheath component polymer slit discharge hole 8.

As described above, the spinneret for spinning the core-sheath composite fiber of the present invention supplies the two kinds of polymers separately and discharges them, thereby making the core-sheath flow immediately after the discharge. Produce composite fibers. For further details, see the base plate 3
The sheath component polymer is discharged from the lower sheath component polymer slit discharge hole 8, and the sheath component polymers are bonded to each other immediately below the base plate to form fibers. At the same time, the core component discharge hole independent of the sheath component polymer slit discharge hole 8 is formed. 7 core component polymer A
Is discharged, the core component enters the inside of the sheath component fiber to form a core-sheath composite fiber.

At this time, a core-sheath composite hollow fiber can be obtained by using a slit orifice having one or more discontinuous portions arranged in an annular or polygonal shape in the sheath component slit orifice.

As described above, in order to form the core-sheath composite fiber or the core-sheath composite hollow fiber as described above, it is necessary to completely separate the core component polymer and the sheath component polymer flow paths.

As the upper introduction plate 1 and the lower introduction plate 2, introduction plates used in a general core-sheath composite die device can be used, but the core component polymer and the sheath component polymer are introduced into the die plate without merging. Therefore, it is necessary to have independent core component polymer and sheath component polymer flow paths. Further, even if the lower introduction plate 2 is not used, the effect of the present invention is not affected at all.

Next, as shown in FIG. 2, a core component polymer introduction hole 4 and a sheath component polymer introduction hole 5 are formed in the periphery of the core component plate 3 as shown in FIG. The sheath component introduction hole 5 may be a round hole or a slit hole, but when the lower introduction plate 2 is used, it may be formed at a position corresponding to the sheath component supply hole 12 of the lower introduction plate 2. preferable. Furthermore, when a plurality of sheath component polymer introduction holes are arranged, it is preferable to make the discharge amount per hole the same in order to obtain a stable fiber. It is preferable that the holes are formed at the symmetry point, that is, on the same track.

In addition, as shown in FIG. 3, the base plate 3 requires that the core component flow channel 13 and the sheath component flow channel 14 be completely independent. More specifically, the core component flow path 13 does not allow the core component polymer introduced from the core component polymer introduction hole 4 in the upper part of the die plate 3 to merge with the sheath component polymer to the core component polymer discharge hole 7 in the lower part. Need to be an independent flow path for guiding the flow. Further, the sheath component polymer flow path 14 joins the sheath component polymer introduced from the sheath component polymer introduction hole 5 in the upper part of the die plate 3 once, and the core component polymer flow path 1
3 is a flow path that leads to the slit discharge hole 8 at the lower part of the base plate 3 along the periphery of the base 3. By discharging the core component polymer and the sheath component polymer without merging, the discharge of the core component polymer due to the pressure of the sheath component polymer is eliminated, and furthermore, the kneeling phenomenon that occurs when the composite flow is introduced into the circular arc slit does not occur. Stable core-sheath composite fibers and core-sheath composite hollow fibers can be obtained.

Next, the shape of the discharge hole of the die plate for finally discharging will be described with reference to FIG. The position of the core component polymer ejection hole located inside may be within the inscribed circle of the slit ejection hole, but is preferably located at the center. The shape of the core component polymer discharge hole may be a modified hole or a round hole, but is preferably a round hole. The shape of the sheath component polymer discharge hole may be linear or arcuate, but is preferably arcuate. Further, the sheath component polymer slit discharge hole can form a hollow by having one or more discontinuous portions.

The polymer applied to the core-sheath composite fiber spinneret of the present invention is not particularly limited.
Examples include all thermoplastic polymers and copolymers such as polyolefins such as polyethylene and polypropylene, polyamides such as nylon 6 and nylon 66, polyethylene terephthalate and polybutylene terephthalate. Further, a third component may be mixed with the polymer, or particles may be added for use. Further, the polymers used for the core component and the sheath component can be freely combined and used from the above-mentioned polymers.

FIG. 5 shows the cross-sectional shape of the fiber obtained by using the spinneret for spinning the core-sheath composite fiber. FIG. 5 is a cross-sectional view showing an example of a cross section of the core-sheath composite fiber after spinning and drawing, in which 15 is a core portion, 16 is a sheath portion,
17 is a hollow part.

With the above described core-sheath composite fiber spinneret of the present invention, ejection unevenness of the core component polymer when the core component polymer having a low melt viscosity and the sheath component polymer having a high melt viscosity are used as core-sheath composite fibers. In addition, when a polymer having high reactivity is used as the core component, the reaction at the contact interface between the molten polymers can be suppressed even in the core-sheath composite flow inside the die plate. Further, a core-sheath composite hollow fiber having a hollow portion at the core-sheath interface of the core-sheath composite fiber can be obtained with good operability without hollow cracking.

[0023]

The present invention will be described in more detail with reference to the following examples. Each characteristic value in the examples was obtained by the following method.

A. Intrinsic viscosity [η] orthochlorophenol (hereinafter referred to as OCP) 10 ml
Was dissolved in 0.10 g of the sample, and the temperature was measured at 25 ° C. using an Ostwald viscometer.

Example 1 Polyethylene terephthalate having an intrinsic viscosity [η] of 0.64 was used as a sheath component, and an intrinsic viscosity [η] of 0.1 was used as a core component.
At 45, the 5-sodium sulfoisophthalic acid component is added to 2.5
Using a modified polyester obtained by copolymerizing mol%, a three-part sheath composed of a slit having a discharge hole shape of 0.4 mm and a slit width of 0.08 mm in a discharge hole shape shown in FIG. Using the die device of FIG. 1 in which a component polymer slit discharge hole and a die plate composed of independent core component polymer discharge holes having a diameter of 0.20 mm are combined,
The core-sheath composite ratio was discharged at 20:80, and the undrawn yarn was wound up at a spinning speed of 1350 m / min. The melt viscosity of the single polymer of each of the sheath component and the core component is 3000 poise, 150
It was 0 poise. Further, the undrawn yarn is drawn at a draw ratio of 2.8 using a normal hot roll / hot plate drawing machine.
It was drawn by a factor of 2 to obtain a drawn yarn. The operability at this time was good without breakage.

The drawn yarn had a desired cross-sectional shape having a hollow portion at the core-sheath interface shown in FIG.

COMPARATIVE EXAMPLE 1 A conventional die plate shown in FIG. 6 was used as a die plate and led to discharge holes as a core-sheath composite flow, and the discharge hole radius shown in FIG.
m, spinning and stretching under the same conditions as in Example 1 except that a slit discharge hole having a slit having a slit width of 0.08 mm and a final discharge hole having a discharge hole having a diameter of 0.20 mm were used. Yarn was obtained. In this yarn, a kneading phenomenon occurs in the slit discharge hole in the spinning process, and there are many yarn breaks in the spinning and drawing processes. Further, when the cross-sectional shape is observed as shown in FIG. It was low.

[0028]

The spinneret for spinning a core-sheath composite fiber according to the present invention comprises:
By separating the core component polymer flow path and the sheath component polymer flow path and discharging them independently, even if a polymer having a lower viscosity than the sheath component polymer is used as the core component polymer, there is no uneven discharge of the core component polymer and stable. And the reaction occurring at the contact interface between the molten polymers can be suppressed. Further, it is possible to avoid a kneeling phenomenon that occurs when the composite flow is discharged from the slit discharge holes. Further, the sheath component polymer is discharged from an annular sheath component polymer slit discharge hole having one or more discontinuous portions, and the core component polymer is discharged from the core component polymer discharge hole independent of the sheath component polymer slit discharge hole. Thereby, a core-sheath composite hollow fiber having a hollow portion at the core-sheath interface can be manufactured with good operability.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an example of a base device of the present invention.

FIG. 2 is a top view of a die plate showing an example of an independent hole for introducing a core-sheath component polymer in the upper part of the die plate of the present invention.

FIG. 3 is a longitudinal sectional view of a base plate showing an example of an independent core-sheath component polymer flow path in the base plate.

FIG. 4 is a bottom view of a base plate showing an example of a sheath component polymer discharge hole formed of a slit formed in a base plate and a core component polymer discharge hole independent of the sheath component discharge hole.

FIG. 5 is a cross-sectional view showing an example of a cross section of a core-sheath composite hollow fiber obtained using the die plate of the present invention.

FIG. 6 is a longitudinal sectional view of a conventional die plate.

FIG. 7 is a cross-sectional view showing an example of a discharge hole of the die plate of FIG. 6;

8 is a cross-sectional view of a fiber obtained by the die plate of FIG.

[Explanation of symbols]

 1: upper introduction plate 2: lower introduction plate 3: base plate 4: core component polymer introduction hole 5: sheath component polymer introduction hole 6: discharge hole 7: sheath component polymer slit discharge hole 8: core component polymer discharge hole 9: upper part Introductory plate core component polymer supply hole 10: Upper introduction plate supply port 11: Lower introduction plate core component polymer supply hole 12: Lower introduction plate sheath component polymer supply hole 13: Core component flow path 14: Sheath component flow path 15: Core part 16: Sheath 17: Hollow

Claims (3)

[Claims] 1. A die plate having a sheath component polymer flow path and a core component polymer flow path independent of the sheath component polymer flow path, comprising a slit arranged in an annular or polygonal shape as a discharge hole. A spinneret for spinning a core-sheath composite fiber, comprising a sheath component polymer ejection hole and a core component polymer ejection hole that is independent of the sheath component polymer ejection hole. 2. The core-sheath conjugate fiber according to claim 1, wherein the sheath component polymer ejection hole is an ejection hole composed of slits arranged in an annular or polygonal shape having one or more discontinuous portions. Spinneret plate. 3. A base device which is integrally formed vertically in the order of a single or a plurality of introduction plates and a base plate, wherein both the introduction plate and the base plate have independent flow paths for the core component polymer and the sheath component polymer. A cap component having a sheath component polymer flow path and an independent core component polymer flow path inside the sheath component polymer flow path, and a sheath component comprising slits arranged in an annular or polygonal shape as discharge holes. A spinneret for spinning a core-sheath composite fiber, wherein a polymer discharge hole and an independent core component polymer discharge hole are arranged inside the sheath component polymer discharge hole.