JP2007321295A - Crimped conjugated fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conjugated fiber which has a moisture-absorbing property and whose crimped form is reversibly changed by ambient humidity. <P>SOLUTION: This crimped conjugated fiber is characterized by bonding a polyamide-based polymer to a polyetheresteramide-based polymer in a side-by-side form, satisfying the following characteristics (1) and (2), and having a reversibly crimping ability: (1) a coefficient of moisture absorption is 2 to 10% at 20°C, 65% RH; and (2) MR2-MR1=5 to 20%, wherein MR2 and MR1 are coefficients of moisture absorption at 20°C, 65% RH and at 35°C, 95% RH, respectively. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a side-by-side reversible crimped conjugate fiber having moisture absorption / release properties, comprising a polyamide polymer and a polyether ester amide polymer.

Conventionally, fabrics using synthetic fibers have been widely used in various applications including apparel because of their good handleability. On the other hand, many synthetic fibers are more hydrophobic than natural fibers, and characteristics such as air permeability and moisture permeability do not change even if the surrounding humidity changes. For this reason, when such a fabric is worn and exercised, there is a problem that the moisture in the clothes increases due to perspiration, and the stuffiness becomes uncomfortable.
On the other hand, in fabrics using natural fibers such as cotton and wool, the fiber itself absorbs moisture when the surrounding humidity is high, and the bulkiness of the fiber is self-regulated by roughening the crimped shape of the fiber. It has been known.

  Various attempts have been made to improve the hygroscopicity of synthetic fibers following such natural fibers. For example, a method of mixing a resin having high hygroscopicity or water absorption performance with a fiber-forming resin, or a method of grafting or applying a hydrophilic compound on the fiber surface is known. These methods have drawbacks such as defective processes in yarn production, characteristics inherent to the fiber-forming resin itself, and loss due to washing and friction.

Further, Patent Document 1 (Japanese Patent Laid-Open No. 11-279871) aims at effects such as crimping a moisture-absorbing / releasing fiber comprising a moisture-absorbing / releasing component and a fiber-forming polymer to suppress stickiness during moisture absorption. Fibers are presented. However, the fiber provided here does not change the crimped form greatly when the surrounding humidity is high, like natural fiber, and it gives sufficient comfort when used as a fabric. There are disadvantages that are not.
Various attempts have been made to provide a crimping self-regulating function by moisture absorption. For example, in Patent Document 2 (Japanese Patent Publication No. 63-44843) and Patent Document 3 (Japanese Patent Publication No. 63-44844), a composite fiber in which a modified polyethylene terephthalate and nylon are bonded in a side-by-side manner, the moisture absorption of nylon. It proposes a method of changing crimp by using expansion and contraction.
However, in this method, the fiber cross section is deformed in the stretching process, false twisting process, and weaving process, and there are defects such as peeling on the bonded surface of polyethylene terephthalate and nylon, which is not practical.
Japanese Patent Laid-Open No. 11-279871 Japanese Patent Publication No. 63-44843 Japanese Patent Publication No. 63-44844

  The present invention has been made against the background of the above-described prior art, and an object thereof is to provide a composite fiber that not only has hygroscopicity in the fiber but also reversibly changes its crimped form depending on the ambient humidity. There is to do.

As a result of intensive studies to achieve the above object, the present inventor made a polyamide-based polymer and a polyether ester amide-based polymer into a bonded composite cross-sectional fiber, specified its moisture absorption rate and moisture absorption / release property, and was reversible. The present inventors have found that fibers and fabrics excellent in self-humidity can be obtained by imparting crimpability to the present invention.
That is, according to the present invention, the polyamide polymer and the polyether ester amide polymer are joined in a side-by-side manner, satisfying the following (1) and (2), and having a reversible crimping capability: A crimped composite fiber is provided.
(1) 2-10% moisture absorption at 20 ° C. and 65% RH
(2) MR2-MR1 = 5-20%
(Here, MR1 and MR2 represent moisture absorption rates at 20 ° C. and 65% RH and 35 ° C. and 95% RH, respectively).
Here, the polyether ester amide polymer preferably has a water absorption of 40 to 200%.

  In the crimped composite fiber of the present invention, not only the crimped form reversibly changes, but each component constituting the composite fiber has specific moisture absorption performance and moisture absorption / release performance, and as a result, the fiber itself. A fiber having moisture absorption / release performance can be obtained. Therefore, when this is used as a fabric, it is possible to provide a fabric having a function of self-adjusting the temperature and humidity in the clothes according to the surrounding environment.

In the present invention, a polyamide-based polymer and a polyether ester amide-based polymer are used as a polymer component for forming a side-by-side type composite fiber.
Here, examples of the polyamide-based polymer include nylon-6, nylon-66, nylon-610, nylon-11, nylon-12, and the like. Among them, nylon-6 is a process stability, cost, etc. To preferred.

In addition, as for the polyamide-type polymer used for the crimped composite fiber of this invention, it is desirable to use the said MR2-MR1 5% or more. Therefore, it is preferable to mix a moisture absorption / release component with the polyamide-based polymer. As the moisture absorbing / releasing component, polyalkylene oxide is preferable, and polyethylene glycol having a molecular weight of 4,000 to 20,000 is particularly preferable. It is possible to make MR2-MR1 ≧ 5% by mixing moisture absorption / release components with the polyamide-based polymer in advance or before melting and blending at the time of melting.
The amount of the polyalkylene oxide to be blended in the polyamide polymer is preferably 2 to 40% by weight, more preferably about 5 to 25% by weight, based on the polyamide polymer + polyalkylene oxide.

Moreover, as a polyetheresteramide type polymer, the block copolymer which consists of a polyamide formation component and a polyetherester formation component can be mentioned. Examples of the polyamide-forming component include lactams such as caprolactam, aminocarboxylic acids such as aminocaproic acid, and diamine-dicarboxylic acid nylons that are precursors such as nylon-66, nylon-610, and nylon 6,12. Examples of the polyether ester-forming component include those composed of a dicarboxylic acid and a polyalkylene oxide glycol. Examples of the dicarboxylic acid include aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, and dodecadiic acid, and aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid. Examples thereof include alicyclic dicarboxylic acids such as acid and 1,4-cyclohexanedicarboxylic acid, and one or a mixture of two or more can be used. Preferred dicarboxylic acids are adipic acid, sebacic acid, dodecadiic acid, terephthalic acid and isophthalic acid. Poly (alkylene oxide) glycols include polyethylene glycol, poly (1,2- and 1,3-propylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, ethylene oxide and propylene oxide or Examples thereof include random or block copolymerization with tetrahydrofuran, and it is particularly preferable to use polyethylene glycol in order to impart hygroscopicity.
The polyether ester amide polymer can be obtained by polycondensation of the polyamide-forming component and the polyether ester-forming component.
It is important that the polyether ester amide polymer has a water absorption of 40 to 200%, preferably 60 to 150% when placed in water at 20 ° C. for 24 hours. If it is less than 40%, sufficient hygroscopicity and moisture absorption / release characteristics cannot be imparted to the resulting composite fiber. In addition, when the water absorption rate exceeds 200%, it is not preferable because it causes a complicated drying process and color spots at the time of dyeing.

In the present invention, the polyamide polymer and the polyether ester amide polymer are bonded side-by-side in the fiber cross section. This polymer combination has good adhesion on the bonding surface, and the reversibility of the crimped form due to changes in humidity appears.
The crimped conjugate fiber according to the present invention has (1) a moisture absorption rate of 2 to 10% at 20 ° C. and 65% RH, and (2) MR2−MR1 = 5 to 20% (where MR1 and MR2 are each 20 The moisture absorption at 35 ° C., 95% RH). 20 ° C. and 65% RH are assumed to be in an ordinary standard atmosphere, and 35 ° C. and 95% RH are assumed to be a high temperature and high humidity state. Preferably, (1) the moisture absorption rate at 20 ° C. and 65% RH is 3-8%, (2) MR2-MR1 is preferably 7-15%.
If the moisture absorption rate at 20 ° C. and 65% RH is less than 2%, the hygroscopicity is not excellent, and the composite fiber that has once absorbed moisture cannot be quickly released outside the garment where the temperature and humidity are lower than in the garment. In addition, when it exceeds 10%, an unpreferable characteristic arises depending on uses, such as a cold feeling.
Moreover, when MR2-MR1 is less than 5%, the moisture absorption performance under high humidity and the moisture release when the surroundings are in a low humidity state are insufficient. In addition, when it exceeds 20%, when used as clothes, it is not preferable because there is a possibility that the original regulation function of the body may be hindered because it changes so much.

In order to satisfy the above condition (1) in the crimped conjugate fiber of the present invention, a thermoplastic polymer having a moisture absorption rate in a desired range may be selected and yarn-formed. If the moisture absorption rate of one polymer is low, it is only necessary to use a highly hygroscopic material for the other polymer. Also, satisfying the above condition (2) may be the same as (1) using a desired hygroscopic polymer. .

The crimped conjugate fiber of the present invention has reversible crimping ability. Here, the reversible crimping ability includes a crimping rate TCs under a standard condition of 20 ° C. and 65% RH and a crimping rate TCh crimping rate under a high humidity of 35 ° C. and 95% RH. It is designated as reversible change.
The crimped conjugate fiber of the present invention preferably has a crimp rate TCs of 2 to 10%, more preferably 3 to 8%, 35 ° C and 95% RH under a standard state of 20 ° C and 65% RH, for example. The crimp rate TCh under high humidity is preferably 5 to 15%, preferably 4 to 12%.
The reversible crimping ability can be achieved by forming a composite fiber in which the polyamide polymer and the polyether ester amide polymer are joined in a side-by-side manner and stretching at a predetermined temperature.

If the crimped conjugate fiber of the present invention is a side-by-side type, it can have any fineness and cross-sectional shape. The composite ratio of both components is preferably in the range of 30:70 to 70:30, more preferably 40:60 to 60:40, in terms of area ratio. In addition, the spinning speed of the composite spinning is higher as the crimp speed of the obtained fiber is better, but the crimped fiber that can be used practically is 700 m / min or more, preferably 1,000 m / min. Spinning at ˜1,500 m / min.
Furthermore, after winding the unstretched yarn thus composite-spun once, or a fiber by a method of continuously stretching after spinning, from the aspect of initial crimp expression and winding stabilization, A method of continuously stretching is preferably used rather than winding it once. The draw ratio in that case is 1.5-5 times, and 2.5-4 times is used preferably. The heat setting before winding is preferably performed at 100 ° C. or less, preferably 60 ° C. or less, preferably 20 ° C. or more, because the fiber physical properties deteriorate when the yarn of the present invention is heated too much.
The yarn thus obtained is heat-treated under a load that does not hinder crimping under boiling water of 100 ° C. or dry heat of 100 ° C. or more and 160 ° C. or less in order to further develop crimping. It is preferable.

  Hereinafter, the present invention will be described more specifically with reference to examples. In addition, unless otherwise indicated, the part and% in an Example are a basis of weight, and each measured value was calculated | required according to the following method, respectively.

<Hygroscopic rate>
The fiber is knitted into a tube and cut to a weight equivalent to 2 g. After drying at 80 ° C. for 18 hours, the weight after drying for 18 hours is set to W0, and then left at 20 ° C. in a 65% RH atmosphere for 2 hours. Subsequently, the weight after standing for 2 hours at 35 ° C. and 95% RH was measured, and the moisture absorption rate MR was calculated from the weight W after standing for 2 hours by the following equation. The moisture absorption rate under 20 ° C., 65% RH and 35 ° C., 95% RH was calculated as MR1 and MR2 by measuring W in each atmosphere.
MR (%) = [(W−W0) / W0] × 100

<Crimping rate>
A crimped composite fiber yarn was placed in a skein of 30 cm in length, a load of 220 mg / dtex was applied, the length after standing for 1 minute was measured, and the length was defined as L0. Then, after heat-treating the crimped composite fiber yarn, the lengths L1 and L2 after being left for 1 minute under a load of 220 mg / dtex and a load of 2.2 mg / dtex are measured, and the crimp rate ( TC) was calculated.
TC (%) = [(L1-L2) / L0] × 100
Note that the crimp rate TCs under standard conditions of 20 ° C. and 65% RH and the crimp rate TCh under high humidity of 35 ° C. and 95% RH are the same for L1 and L2 in each of the above atmospheres. It calculated from the measured value after leaving each for 2 hours.

<A feeling of wearing>
The resulting fiber was knitted with 80 dtex / 24 fils of polyethylene terephthalate so as to open the mesh as the crimp increased upon moisture absorption, to prepare a knitted fabric. Using this knitted fabric, a T-shirt was prepared, and three subjects were subjected to a wearing feeling test after strong walking for 15 minutes, and evaluated in the following three stages.
○ ... No stuffiness.
Δ: I feel a little stuffy.
X: There is a feeling of stuffiness and stickiness due to sweat.

Example 1
A blend of Nylon 6 having an intrinsic viscosity of 1.1 dL / g as an A polymer and a polyethylene glycol having a molecular weight of 20,000 (measured at 35 ° C.) of 10% by weight, and ε-caprolactam as a B polymer. Separately melt polyether ester amide having a water absorption of 110% when left in water having a melting point of 182 ° C. and 20 ° C. obtained by reacting terephthalic acid and polyethylene glycol having an average molecular weight of 2,000 under reduced pressure, 1 is discharged from a die having 24 holes in a fiber cross section shown in FIG. 1 of a side-by-side type at a spinning temperature of 260 ° C., and taken up at a spinning speed of 1,000 m / min, and subsequently 3,000 m / min at 40 ° C. The film was stretched directly at, and heat-set at a set temperature of 60 ° C., and wound up at 93 dtex. The obtained yarn was treated under boiling water for 20 minutes under no load. The evaluation results of the obtained yarn are shown in Table 1. In addition, the area ratio of A polymer and B polymer is 45/55 (hereinafter the same).

Example 2, Comparative Examples 1-2
Table 1 shows the results of spinning and evaluating in the same manner as in Example 1 except that the change in the A polymer and the polyether ester amide having different water absorption were used as the B polymer.

Comparative Example 3
Implemented except that modified polyethylene terephthalate (o-chlorophenol, intrinsic viscosity measured at 35 ° C. = 0.45 dL / g) obtained by copolymerizing 2.6 mol of 5-sodium sulfoisophthalic acid with polyethylene terephthalate was used as B polymer. Yarn production was carried out in the same manner as in Example 1 and evaluated. The results are shown in Table 1.

Ny6: Nylon 6 having an intrinsic viscosity (measured in m-cresol at 30 ° C.) of 1.1 dL / g
Ny12: Nylon 12 having an intrinsic viscosity of 1.21 dL / g measured at 30 ° C. in m-cresol
PEG: polyethylene glycol having a molecular weight of 20,000 PEEA1: polyether ester amide PEEA2 having a melting point of 182 ° C. and a water absorption of 110% obtained by reacting ε-caprolactam, terephthalic acid and polyethylene glycol having an average molecular weight of 2,000 under reduced pressure. Polyether ester amide having a water absorption of 45%, obtained by reacting ε-caprolactam, terephthalic acid and polyethylene glycol having an average molecular weight of 2,000 under reduced pressure PEEA3: ε-caprolactam, terephthalic acid, polyethylene having an average molecular weight of 2,000 Polyether ester amide PEEA4: 30% water absorption obtained by reacting glycol under reduced pressure PEEA4: Water absorption 2 obtained by reacting ε-caprolactam, terephthalic acid and polyethylene glycol having an average molecular weight of 2,000 under reduced pressure % Polye -Teresteramide PET: Modified polyethylene terephthalate obtained by copolymerizing 2.6 mol of 5-sodium sulfoisophthalic acid with polyethylene terephthalate

  As is clear from Table 1, in Examples 1 and 2, crimped conjugate fibers having excellent moisture absorption and release properties and having a crimped shape change are obtained, whereas in Comparative Examples 1 and 2, absorption and release are obtained. Inferior wetness and fibers with little crimp change are obtained, and in these wearing tests, in Examples 1 and 2, which are within the scope of the present invention, a comfortable wearing feeling without stuffiness is obtained. Was confirmed. Moreover, in Comparative Example 3, although the crimp change is large, the feeling of wearing is inferior, for example, the moisture absorption performance of the fiber itself is inferior and the feeling of stuffiness is felt.

  The crimped conjugate fiber of the present invention has a crimped form that reversibly changes according to the surrounding environment, and because the fiber itself is provided with moisture absorption and desorption, it has excellent wearing feeling when worn as a fabric. It can be suitably used for applications such as sports clothing and innerwear, as well as humidity sensitive filters, and its industrial value is extremely high.

It is one schematic diagram of the cross section of the side-by-side type composite fiber concerning this invention.

Explanation of symbols

1 Polyamide polymer 2 Polyether ester amide polymer

Claims (2)

A crimped composite fiber characterized in that a polyamide polymer and a polyether ester amide polymer are joined in a side-by-side manner, satisfying the following (1) and (2), and having a reversible crimping ability.
(1) 2-10% moisture absorption at 20 ° C. and 65% RH
(2) MR2-MR1 = 5-20%
(Here, MR1 and MR2 represent moisture absorption rates at 20 ° C. and 65% RH and 35 ° C. and 95% RH, respectively). 2. The crimped conjugate fiber according to claim 1, wherein the polyetheresteramide polymer has a water absorption of 40 to 200%.