JPS6183313A - Porous conjugated yarn - Google Patents

Abstract

PURPOSE:The titled yarn having a crosssectional shape changing reversibly and rapidly when it absorbs moisture or water and it is dried, obtained by bonding a water-swelling polymer part to a dent part at approximately the center of the outside of folded part or bent part of hydrophobic polymer part. CONSTITUTION:The crosssectional shape of the hydrophobic polymer part 1 is a shape obtained by folding or bending a slit flat shape n times (n is >=1) and has n protrusion parts. At least one protrusion pat has a dent at approximately the center of the outside of folded part or bent part, the water-swelling polymer part 2 is bonded to the dent part, the hydrophobic polymer part has the fine pore 3, and at least part of the fine pore is communicated with the water-swelling polymer part.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a porous conjugate fiber whose cross-sectional shape reversibly and rapidly changes during moisture absorption and during water absorption and drying conditions. It is.

<Conventional technology> In recent years, there has been a strong demand for comfortable materials for clothing materials, especially for clothing materials in the sports field, and various textile manufacturers have developed materials with moisture permeability, waterproofness, heat retention, and sweat absorption.
Various functional materials with functions such as wicking properties are commercially available.
Development is continuing. However, most of these so-called functional materials are fabrics that do not have functionality and are made functional by coating them with resin or laminating them with films. It involves multiple Nl processes,
There are problems such as the texture of textile products becoming dull.

On the other hand, we also improve the polymer at the yarn stage.

By making the fibers have irregular cross-sections or hollow porous properties, they can absorb
There are some products that have functions such as water absorption.

When these are made into woven or knitted fabrics, they have the disadvantage that the balance between physical properties and performance (drying speed, heat retention, etc.) of the woven or knitted fabrics is poor.

<Problems to be Solved by the Invention> In view of the current situation, the present inventors have conducted intensive studies to develop a yarn that can reflect the functionality of the yarn even in the constrained state of the fabric. 5 The present invention has been achieved.

In other words, in the present invention, by imparting latent multifunctionality to the raw yarn, even when it is made into a woven or knitted fabric, or when it is used in combination with other fibers through high-order processing to form a multilayer structure. , which can demonstrate multifunctionality and further improve the functionality of conventional post-processing.
This is a technical problem that involves rubbing.

<Means for Solving the Problems> The present invention achieves the second object, and is a composite fiber made of a hydrophobic polymer and a water-swellable polymer, the cross section of the composite fiber being hydrophobic. The cross-sectional shape of the polymer portion is a slit-like flat shape bent 0 times (n is an integer of 1 or more) or a bent shape.

n convex portions, and at least one convex portion has a bent portion or a concave portion at approximately the center of the outside of the bent portion, and a water-swellable polymer portion is bonded to the concave portion. Then,
The porous composite fiber is characterized in that the hydrophobic polymer portion has micropores, and at least 4) a portion of the micropores communicate with the water-swellable polymer portion.

1. The present invention will be further explained in detail below.

The porous composite fiber of the present invention is first a composite yarn 11 made of a hydrophobic polymer and a water-swellable polymer.

The hydrophobic polymer in the present invention is) 11. Well-known polyalkylene terephthalates such as polyethylene terephthalate and polybutylene terephthalate, and polyesters containing these as main components.

Nylon 6, nylon 12. nylon 66, nylon 6
10, polyamide 1', polyethylene, polypropylene, etc., and polyolefins containing these as main components, which have relatively low water absorption, and one or more of these hydrophobic polymers. They can be used in combination. It is also possible to appropriately mix additives such as matting agents, heat-resistant agents, weather-resistant agents, and pigments into these hydrophobic polymers.

The water-swelling polymer used in conjunction with the hydrophobic polymer is preferably one that is substantially insoluble in water. For example, a copolymer of polyethylene oxide and polyethylene terephthalate, an olefin-modified polyvinyl alcohol,
Specially treated polyvinyl alcohol, crosslinked structures of polyvinyl lactams and polyvinyl pyrrolidone such as polyvinyl pyrrolidone, and mixtures of these polymers with polyesters or polyamides are preferably used.

2. In the porous composite fiber of the present invention, the cross-sectional shape of the hydrophobic polymer portion is a shape in which a slit-like flat shape is bent or bent 0 times (n is an integer of 1 or more), and has n convex portions. , and at least one convex portion has a recessed portion approximately at the center of the outside of the bent portion or the bent portion,
A water-swellable polymer portion is bonded to the recessed portion.

Since the porous composite fiber of the present invention also consists of [1], the water-swellable polymer absorbs moisture and its volume changes due to water absorption, that is, the area change of the water-swellable polymer portion in the cross section of the fiber. By using.

The fiber cross-sectional shape changes reversibly between moisture absorption and water absorption and drying, and has potential multifunctionality.

FIG. 1 shows a specific example of the cross section of the porous composite fiber of the present invention, and FIG. 1(a) shows the hydrophobic polymer portion (1).
When the cross-sectional shape of (b+) is V-shaped and the water-swellable polymer portion (2) is joined to the concave part of the convex portion, the cross-sectional shape of the hydrophobic polymer portion (1) of the same (b+) is U-shaped. in.

When the water-swellable polymer portion (2) is joined to the concave portion of the convex portion, the hydrophobic polymer portion (1) (C4) is
When the water-swellable polymer portion (2) is bonded to the concave portion of each convex portion, the hydrophobic polymer portion (1) is ) is W-shaped, and the water-swellable polymer portion (2) is bonded to the concave portion of one of the two convex portions. ), (b+), (c, ) and (dl) are cross sections when the water-swellable polymer portion (2) is dry and unswollen; C2
) and (d2) respectively show cases where the water-swellable polymer portion (2) absorbs moisture and swells by absorbing water. (
In FIG. 1, micropores are omitted except for (a,).

) As is clear from FIG. 1, the porous composite fiber of the present invention starts from the water-swellable polymer portion (2).

The hydrophobic polymer part (the part where 1 and 1 are joined at a certain angle in two directions is at least 1 in the ♀1 & fiber 1ui plane)
(It is important that the V
In addition to a U-shape, a W-shape, a cross-sectional shape such as an S-shape or a 7-shape is preferable. However, as shown in Figure 2, starting from the water-swellable polymer part (2), the hydrophobic polymer part (1)
11 has a part joined at an angle in two directions, the two hydrophobic polymer parts (11 are on the side forming a 180° non-grooved angle, and the water-swellable polymer part (2), even if the water-swellable polymer portion (2) swells, the fiber structure ITh surface as a whole changes in the direction of expansion, and 2. It does not become a changing fiber.

In addition, when the water-swellable polymer portion (2) is joined without providing a recess on the outside of the convex portion as shown in Fig. 3, the swelling force when the polymer portion (2) swells is the fiber). This is not preferable because it does not act effectively in the direction in which the cross section closes and the swelling force is dispersed in other directions.

Thus, in the present invention, as shown in FIG. 1, it is necessary that the water-swellable polymer portion (2) is joined to the recessed portion on the outside of the convex portion of the cross section of the fiber 1Ifi, and that it does not protrude to the inside of the convex portion. As shown in Figure 4, the part from the center of the inside of the convex part to the point B closest to 8 of the water-swellable polymer part (2) serves as a fulcrum in the lever principle. It is from.

Therefore, the one having the cross-sectional shape shown in FIG. 2 is not preferable because it does not have a portion that corresponds to a fulcrum, so it changes in the direction of expansion.

Here, let C be the central part of the fiber cross section outside the convex part, the distance from 8 to B be tI+, and the distance from B to C be C2.

It is preferable that the relational expression 0.05≦t+/(t++tz)≦0.65 holds true, and more preferably, the value of this expression is in the range of 0.10 to 0.35. If the value of this formula is less than 0.05, the fiber cross section may easily change, but the value of 1+ is small, so
During this change, the degree of deformation near the fulcrum between A and 8 is large, and the durability between A and 8 is undesirable. Also, if the value of this formula exceeds 0.65, the distance between A and 8 is 1. This is not preferable because the value of is large, the fulcrum part lacks flexibility, and the fiber cross section becomes difficult to change.

Although the cross-sectional shape of the water-swellable polymer portion (2) in the cross section of the porous composite fiber of the present invention is not particularly limited,
It is preferable to have a shape close to a circle as shown in FIG. 1, or a shape close to a triangle as shown in FIG. Further, as long as the water-swellable polymer portion (2) is bonded to the recessed portion, there is no problem even if a portion of the polymer portion (2) exists in a raised shape outside the convex portion of the cross section of the fiber ( In Fig. 3, there is no recess on the outside of the convex portion, so it cannot be considered a wooden invention, but if it has a recess, it is included in the present invention.)

In addition, in the porous composite fiber of the present invention, Fig. 5 (G
l, as shown in (f), the hydrophobic polymer portion (1)
When both ends of the fiber cross section are D and E, and the joints between the hydrophobic polymer part (J) and the water-swellable polymer part (2) are F and G on the outer periphery of the fiber cross section, water M・υ Another important point is to design the cross-sectional shape of the fibers so that a small degree of swelling of the wettable polymer portion (2) can greatly change the cross-sectional shape of the fibers.

Note that the degree of water swelling is expressed by the following formula.

Degree of water swelling - (S' -5)/Sx 100 (%) However, S: Area occupied by the water-swellable polymer portion of the cross section of the fiber in the unswollen state S'': Cross section of the fiber in the swollen state The area occupied by the water-swellable polymer portion of the surface The present inventors conducted various studies in order to effectively utilize the slight degree of swelling of the water-swellable polymer portion (2), and in FIG. Angle made by AE (ZIIAIE) and -1
It was found that the angle between BF and BG (lFBG) is an important factor. That is, 1 DAE is 15° to 15
The angle is preferably 0°, and particularly preferably 20' to 120°. Also.

On the other hand, 1FBG is preferably 15° to 140°, especially 20°
Preferably, the angle is between 120° and 120°.

If one or both of the ranges of z DAE and: The change is small (even if the rate of change is a large value, the change itself is small), and a water-swellable polymer having an insufficient or extremely high degree of swelling is required, which is undesirable from a practical standpoint. Furthermore, if /rlAE and lFBG each exceed the 2 limit, a water-swellable polymer having a very large degree of swelling is required, which is not preferable.

Furthermore, in the porous composite fiber of the present invention, the hydrophobic polymer portion has micropores, and at least a portion of the micropores communicate with the water-swellable polymer portion.

In this way, the porous composite fiber of the present invention is shown in Figure 1 (al.
) As shown in the hydrophobic polymer portion (1)? ri!
! By forming pores (3), the water absorption rate of the water-swellable polymer is increased, increasing the water absorption rate and water absorption amount of the entire fiber, and the water-swellable polymer portion (2) is connected to the water-swellable 1-1 polymer portion (2). The micro 15 circular holes (3) serve as mim holes to release excess moisture in the water-swellable polymer to the outside of the fiber, thereby increasing the drying rate of the water-swellable polymer and, therefore, the drying of the entire fiber. It increases the speed.

To produce the porous composite fiber of the present invention, a hydrophobic polymer containing a substance soluble in a solvent and a water-swellable polymer are composite-spun using a spinning material having spinning holes described below. The obtained undrawn yarn is stretched by a conventional method to obtain a drawn yarn. Next, this drawn yarn (or the fabric) is subjected to a solvent extraction treatment to obtain a hydrophobic f! 1: By eluting at least part of the soluble substances contained in the polymerization-controlled polymer alloy and forming micropores, 3
The porous composite fiber of the present invention can be obtained. In this case, the substances soluble in the solvent include halogenated alkali metal salts such as lithium chloride and calcium dichloride, halogenated alkaline earth metal salts, alkyl sulfates of alkali metals or ε4 alkaline earth metals, and polyethylene Organic polymer compounds such as glycol, polyethylene glycol monomethyl ether, polyethylene glycol dimethyl ether, etc.
Any material can be used, but it is easy to mix uniformly with hydrophobic polymers.

Preferably, the material does not have chemical bonding properties with hydrophobic polymers and water-swellable polymers.

Further, as a solvent for the substance, any solvent may be used as long as the hydrophobic polymer and the water-swellable polymer are insoluble. However, if the hydrophobic polymer is polyester and the substance soluble in the solvent is a water-soluble If selected, water can be used as a solvent, and micropores can be formed at the same time in the post-processing alkali reduction process, so no special process is required for forming micropores, and the varnish is inexpensive. preferable.

FIG. 6 is a specific example of the shape of the spinning hole of the spinneret used when spinning the composite fiber of the present invention, and FIG.
l is V-shaped, fh) is W-shaped, and (i) is used when spinning a conjugate fiber having a U-shaped cross section. Composite fibers suitable for the present invention can be obtained by appropriately selecting the spinning holes of these spinnerets, such as the diameter of the circular holes, the angle of the 1+i random slit corner between the slits, and the angle of the corner of the adjacent slits. I can do it. For example, in Figure 6 (gl
In order to perform spinning using a spinning hole of It is possible to adjust LI+t2 (not shown in FIG. 4) and 1FBG (not shown in FIG. 5), and ZDAE (not shown in FIG. 5) by the angle (eI) formed by the two slits or the lozenge temperature.

(Function) When the water-swellable polymer is not swollen, the porous conjugate fiber of the present invention having the above-mentioned structure can be used.

Figure 1 (a+), (b,), (c+) and (d,)
As shown in Figure 2, the cross section of the fibers is open, and when knitted into a knitted fabric, the inter-fiber voids are closed.

Increases heat retention effect. In addition, when the water-swellable polymer swells, Fig. 1 (az), (bz), (C2) and (
As shown in d2), the fiber cross section becomes closed,
When made into a woven or knitted fabric, the voids between the fibers open, making it breathable.

It will exhibit moisture permeability. Furthermore, the micro 11 tl pores in the porous composite fiber of the present invention increase water absorption amount and water absorption rate, and the micro pores communicating with the water-swellable polymer portion allow the water-swellable polymer to absorb water. When wetted, it acts as a through hole for releasing excess water to the outside of the fiber, thus speeding up the drying rate of the water-swellable polymer. The principle behind this principle is that when the humidity is high, such as during the rainy season, the Shosoin building's warehouse structure closes the gaps to allow outside moisture to flow out, and when the humidity is low, such as during the winter, the gaps are opened to ventilate the outside air. The porous composite fiber of the present invention is similar in principle and wood quality, and can be called a porous composite fiber of the present invention.

<Examples> Hereinafter, the present invention will be specifically explained based on Examples.
In the examples, the rate of change and the rate of recovery are expressed by the following equations.

However, d: the distance between E when the water-swellable Ni1 polymer is applied in an unswollen state, d": the distance between E when the water-swellable Ni1 polymer is swollen, and the distance between E"11 d"; Glue when the water-swellable polymer returns from a swollen state to a dry state.

Distance between E m1
Figure 6 (g+ Composite spinning was performed using a 12-hole spinneret with the spinning hole shape shown in the figure and various dimensions, and winding was performed at a speed of 1400 m/min, and the resulting undrawn yarn was drawn at a drawing ratio of 2.8 by a conventional method
．． It was stretched at a stretching speed of 715 m/min, and various +5. t2+ 1
It was made into a drawn yarn of 50d/12r having rlAIi and 4FBG. These drawn yarns were immersed in water for 60 minutes to elute polyethylene glycol dimethyl ether,
Micropores were formed to obtain porous composite fibers.

When a cross section of these porous composite fibers was observed using a scanning electron microscope, it was found that some of the micropores communicated with the water-swellable polymer portion.

Next, these porous composite fibers were immersed in water for 10 minutes, and the rate of change of the copolymerized polyester (water-swellable polymer) from the unswollen state to the swollen state and the rate of change from the swollen state to the drying state were measured. The recovery rate up to the non-swollen state was investigated and the results are shown in Table 1.

Table 1 Also, 1 A woven fabric is made using the drawn yarn of the porous composite fiber of the present invention, and for comparison, a substance soluble in a solvent (polyethylene glycol dimethyl ether) to form pores is not mixed. A woven fabric was made using the drawn yarn obtained in the same manner as above except for the above. These fabrics and cotton fabrics were immersed in water for 10 minutes, then centrifugally dehydrated, and the drying speed was examined. The drying time of fabrics made from composite fibers with a specific ratio was approximately 60% of that of cotton fabrics, whereas the drying time was 1%. The drying time of the fabric obtained from the porous composite fiber of the present invention is approximately 40% that of the cotton fabric.
The drying speed was the fastest.

<Effect of the invention> As described above, the porous composite fiber of the present invention is as follows.

Since it has the above structure, when it is made into a woven flat material, if the water-swellable polymer is not swollen,
The cross section of the fibers is in an open state, and therefore the interfiber voids of the woven or knitted material are in a closed state.

In addition to increasing the heat retention effect, when the water-swellable polymer swells, the cross section of the fibers becomes closed, which opens the inter-fiber voids of the woven or knitted material, which, together with the sweat-absorbing properties of the water-swellable polymer, increases ventilation. Demonstrates durability and moisture permeability.

Moreover, since the porous composite fiber of the present invention has micropores in the hydrophobic polymer portion, it increases the water absorption rate of the water-swellable polymer, increases the water absorption rate and amount of water absorption of the entire fiber, and increases water swelling. The micropores communicating with the water-swellable polymer portion serve as pores for releasing excess water in the water-swellable polymer to the outside of the fiber, increasing the drying rate of the water-swellable polymer, and thus The above-mentioned functions of the fiber can be quickly exerted.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view schematically showing two specific examples of the porous composite fiber of the present invention, in which (a+), (b, L (c+) and (d,) are in an unswollen state. The same figure (az), (bzL) (C2) and (d2) are cross-sectional views of the fiber in the swollen state, Figures 2 and 3 are cross-sectional views of the fiber of the comparative example, and Figure 4 is the cross-sectional view of the fiber in the swollen state. 5 and 5 are fiber cross-sectional views for explaining the dimensions of the composite fiber of the present invention, and FIG. 6 is a diagram showing a specific example of the spinning hole shape of the spinneret for spinning the composite fiber of the present invention. (In Figure 1, micropores are omitted except for (a8).) (1) - Hydrophobic polymer part (21 - Water-swellable polymer part (3) - Micropores)

Claims (1)

[Scope of Claims] 1 A composite fiber made of a hydrophobic polymer and a water-swellable polymer, wherein the cross section of the composite fiber is such that the cross-sectional shape of the hydrophobic polymer portion is a slit-like flat shape n times (n times). is an integer greater than or equal to 1) It has a bent or bent shape and has n convex portions, and at least one convex portion has a concave portion at the bent portion or approximately the center of the outside of the bent portion. , a water-swellable polymer portion is bonded to the recessed portion, the hydrophobic polymer portion has micropores, and at least a portion of the micropores communicates with the water-swellable polymer portion. porous composite fiber. 2 V in which the cross-sectional shape of the hydrophobic polymer portion has one convex portion
The porous composite fiber according to claim 1, which has a shape of a letter or a letter U.