JP2002115123A - Moisture-absorbing/releasing hollow conjugate fiber with parallel-cross-shaped cross section - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight and highly moisture-absorbing/releasing hollow conjugate fiber with parallel-cross-shaped cross section while keeping high thermal insulation, having high comfortableness, peculiar touch feeling and gloss and also functionalities including bulkiness and water repellency. SOLUTION: This conjugate fiber made from a thermoplastic polymer has the following characteristics: the cross sectional shape is square, being parallel- cross shape having two projections 4 approximately rectangular to each other at each of the corners of a square part 5 with a hollow 5 close to the center, the area of the projections 4 accounts for >=30% of the total area of the fiber cross section, percentage bulkiness is >=20%, and as the moisture-absorbing/ releasing component, a polyalkylene oxide modified product obtained by reaction between a polyalkylene oxide, a polyol and an aliphatic isocyanate compound is contained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a polyalkylene oxide-modified product as a moisture-absorbing / desorbing component, and has a hollow well-shaped cross-sectional shape, while maintaining a high heat retention when woven or knitted. The present invention relates to a hollow composite fiber having a well-shaped cross section, which is excellent in moisture absorption and desorption properties and can obtain a fabric having high functionality.

[0002]

2. Description of the Related Art Well-shaped hollow fibers have been developed as synthetic fibers having high added value (Japanese Patent Application Laid-Open Nos. 8-127936 and 10-110).
324). This fiber has a unique texture from a special single yarn cross-sectional shape called a well-shaped cross section, and is excellent due to the dead air part formed by the hollow part and the dead air part formed between the fibers by the protrusion. Light weight and bulkiness,
It has heat retention, and is also excellent in water repellency due to the low contact area of the protrusions with water drops.

[0003] However, while it is excellent in heat retention, there is a problem that moisture is easily trapped in a dead air portion formed by a hollow portion in particular, and when it is used for a cloth for clothing, the comfort is not sufficient depending on use conditions. there were.

Japanese Patent Application Laid-Open No. 8-31719 discloses a moisture-absorbing and desorbing conjugate fiber composed of a core component composed of a mixture of a polyamide or polyester and a crosslinked product of polyethylene oxide, and a sheath component composed of polyamide or polyethylene. Is disclosed.

[0005] These fibers have a performance of absorbing moisture such as sweat and releasing moisture at the same time, and can provide a fabric having high comfort. However, the resulting fabric does not have other properties such as unique texture, gloss, lightness, and heat retaining property, and fibers capable of obtaining a fabric satisfying many of these properties have been demanded.

[0006]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, has a high heat retention property, has excellent moisture absorption and desorption properties, has no moisture, has excellent comfort, and is lightweight and unique. An object of the present invention is to provide a hollow composite fiber having a well-shaped cross section from which a fabric having a texture, a gloss, a bulkiness and a water repellency can be obtained.

[0007]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention. That is, the present invention relates to a well-shaped cross-sectional shape which is formed from a thermoplastic polymer, has a square cross-sectional shape, and has two substantially perpendicular projections at each corner of the rectangular portion having a hollow portion near the center. Is a hollow fiber exhibiting a ratio of 30% of the area of the projections to the total area in the cross section of the fiber.
The bulkiness is 20% or more, and the square portion contains a polyalkylene oxide-modified product obtained by the reaction of a polyalkylene oxide with a polyol and an aliphatic isocyanate compound as a moisture-absorbing and releasing component. The gist of the present invention is a hollow composite fiber having a well-shaped cross section.

[0008] The bulkiness of the fiber in the present invention is defined as
It refers to the ratio of the area of the dead air portion formed by the hollow portion and the projection in the cross section. The measurement method is as follows. A microphotographing device is attached to a microphoto S optical microscope manufactured by Nikon Corporation, and the cross-sectional shape of the cross section of the single yarn is photographed for the five single yarns. As shown in the schematic cross-sectional view, the values of the area A and the area B are calculated and obtained as follows, and the average value of the five is obtained. Bulk (%) = [(Area A) / ((Area A) + (Area B))] × 100

[0009]

Next, the present invention will be described in detail. First, the shape of the well-shaped hollow composite fiber of the present invention will be described with reference to the drawings. FIG. 1 and FIG. 2 are schematic cross-sectional views showing an embodiment of the well-shaped hollow composite fiber of the present invention.
FIG. 1 shows a well-shaped cross-sectional shape having two substantially perpendicular projections 4 at the respective corners of a square part 5 having a hollow part 2 near the center. FIG. 2 shows a core-sheath structure in which the square portion 5 includes the core portion 1 and the sheath portion 3, the core portion 1 contains a moisture-absorbing / desorbing component, and the sheath portion 3 and the projection portion 4 are formed of the same polymer. It is a hollow composite fiber having a core-sheath shape and a well-shaped cross section.

The thermoplastic polymer forming the conjugate fiber of the present invention is not particularly limited, but a polyamide or polyester is preferable.
Nylon 4, Nylon 6, Nylon 11, Nylon 1
2, nylon 46, nylon 66, nylon MXD6
(Polymeta-xylene adipamide), nylon PACM1
Homopolymers such as 2 (polybiscyclohexylmethanedecanamide) and copolymers or mixtures containing these as a main component are preferably used.

As the polyester, an aromatic dicarboxylic acid such as terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid or an aliphatic dicarboxylic acid such as adipic acid or sebacic acid or an ester thereof is used as an acid component; Ethylene glycol, diethylene glycol,
Examples thereof include an ester-based polymer containing a diol compound such as 1,4-butanediol, neopentyl glycol, and cyclohexane-1,4-dimethanol as an alcohol component, or a copolymer thereof. In addition, paraoxybenzoic acid, 5-sodium sulfoisophthalic acid, polyalkylene glycol, pentaerythritol, bisphenol A, and the like may be added or copolymerized to these ester polymers.

As described above, the moisture-absorbing / desorbing component may be contained in the thermoplastic polymer as described above or may be used alone, but generally in the range of 0.5 to 60% by weight based on the total weight of the fiber. Is preferable.

If the content of the modified polyalkylene oxide is less than 0.5% by weight, the desired electrostatic properties and moisture absorption / desorption properties may not be obtained. If the content exceeds 60%, the yarn-forming properties may be reduced. It is not preferable because a problem may occur.

As shown in FIG. 2, in the composite fiber of the present invention having a core-sheath structure having a square-shaped portion, the composite ratio of the core-sheath component varies depending on the polymer used and the degree of required performance. It is preferably 15/85 to 85/15. If the ratio of the core component is lower than this, the moisture absorption / desorption property is inferior, and if the ratio of the core component is too large, a problem may occur in the spinning property, which is not preferable.

The moisture-absorbing / desorbing component is contained in the entire rectangular portion 5 or in the core portion 1. The moisture-absorbing / desorbing component may be contained in a thermoplastic polymer or may be used only with the moisture-absorbing / desorbing component. Is also good. When a moisture absorbing / releasing component is contained in the thermoplastic polymer, it is preferable to use the same thermoplastic polymer as the polymer forming other fiber portions (projections or sheaths) from the viewpoint of spinnability.

The moisture absorbing / releasing component used in the composite fiber of the present invention will be described. The moisture absorbing / releasing component used in the present invention is a modified polyalkylene oxide obtained by reacting a polyalkylene oxide with a polyol and an aliphatic isocyanate compound. By using the aliphatic isocyanate compound in this manner, the yellowing over time due to the imide ring formed by the resonance structure of the isocyanate group and the aromatic as seen when the isocyanate compound is used as the aromatic compound, Coloring is suppressed, and the fiber has excellent weather resistance.

Examples of the polyalkylene oxide include polyethylene oxide, polypropylene oxide, and copolymers and mixtures thereof. Among them, those having a weight average molecular weight of 500,000 to 500,000 are preferable.

As the polyol, ethylene glycol, diethylene glycol, triethylene glycol,
Tetraethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 2,
3-butanediol, 1,4-butanediol, 1,5
-Pentadiol and 1,6-hexadiol are preferred.

The aliphatic isocyanate compound preferably has two isocyanate groups at symmetric positions in the molecule. For example, dicyclohexylmethane-4,4
'-Diisocyanate, 1,6-hexamethylene diisocyanate and the like.

The modified polyalkylene oxide used in the present invention is obtained by reacting the above-mentioned polyalkylene oxide and a polyol with a symmetric aliphatic isocyanate. And this denatured product has a temperature of 170
℃, melt viscosity at an applied load of 50 kg / cm ² is 1000-2
Preferably it is 0000 poise. If the melt viscosity is less than 1000 poise, the gel tends to elute on the fiber surface when absorbing water.On the other hand, if the melt viscosity exceeds 20,000 poise, the dispersibility with polyamide or polyester is reduced, and the spinnability deteriorates. It will be easier. Such a modified polyalkylene oxide is commercially available, for example, from Sumitomo Seika under the trade name "Aqua Coke".

Further, in the hollow composite fiber having a well-shaped cross section of the present invention, it is important that the ratio of the area of the projections 4 to the total area of the cross section of the fiber is 30% or more. When the ratio of the area of the projections is less than 30%, the proportion of the projections in the whole fiber is reduced, and the bulky properties, heat retention, water repellency, etc., which are the original characteristics of the well-shaped cross-section hollow fiber, are provided. The function becomes difficult to express. The upper limit of the ratio of the area of the protrusion is not particularly limited, but is preferably about 60%. If the area ratio exceeds 60%, it becomes difficult to maintain the fiber shape.

Further, it is important that the bulk ratio of the fibers, which is the ratio of the area of the dead air portion between the fibers formed by the hollow portions and the projections in the sectional area, is 20% or more. If the bulkiness is less than 20%, the number of dead air portions formed is too small, and the fabric obtained from this fiber has insufficient heat retention and poor lightness. The upper limit of the bulkiness is not particularly limited,
It is preferred to be about 40%. When the bulk ratio exceeds 40%, if the hollow portion is too large, the fiber tends to have hollow cracks. If the length of the projection is too long, it is difficult to maintain the shape of the fiber, and the obtained fiber is also obtained. The quality of the fabric is likely to deteriorate.

As long as the effects of the present invention are not impaired, matting agents, heat storage and warming agents, modifiers, electric agents, antibacterial agents, deodorants, pigments, etc. May be added.

The hollow composite fiber having a hollow cross section according to the present invention can be produced according to a conventional method for producing a synthetic fiber. When the square portion has a core-sheath structure, it is produced by using a composite spinning apparatus. It is preferable to employ a high-speed melt spinning method in order to manufacture the product with high productivity.

The conjugate fiber of the present invention is formed into a hollow fiber having a well-shaped cross section having moisture absorption / desorption properties, thereby imparting functionality due to the hollow shape of the well cross section, and is also comfortable in terms of moisture absorption / desorption performance. Is more improved. In other words, while the heat retention is improved by the shape of the well-shaped cross-section fiber, as described above, the moisture absorbed inside the fiber is not satisfactorily discharged, and the disadvantage that the fiber is trapped inside is imparted with moisture absorption / release properties. This can be resolved. Furthermore, because of the well-shaped cross-sectional shape, the portion that comes into contact with the skin becomes a projection on the outer periphery of the single yarn,
Since the contact area with the skin is reduced, a dry touch can be maintained even when absorbing moisture. In other words, even when the moisture absorbing / releasing polymer portion expands during moisture absorption, only the protruding portion is in contact with the skin, so that a comfortable tactile sensation can always be maintained. Then, it becomes possible to obtain a fabric which also has functions such as unique texture, gloss, bulkiness and water repellency which are other excellent characteristics of the well-shaped cross-section fiber.

[0026]

Next, the present invention will be described specifically with reference to examples. The evaluation in the examples was performed by the following method. [Bulkiness] The bulkiness was measured by the method described above. [Cross-sectional shape of fiber] A microphotograph photographing device was attached to a Nikon Microphoto S optical microscope, and for five single yarns, the cross-sectional shape of the single yarn was photographed, and the ratio of the area of the protrusion was calculated. The average value was used. (Melt viscosity of modified polyalkylene oxide) Using 1.5 g of modified polyalkylene oxide as a measurement sample,
The measurement was performed using a flow tester (CFT-500D manufactured by Shimadzu Corporation) under the conditions of a load of 50 kg / cm ² , a temperature of 170 ° C., a die diameter of 1 mm, and a die length of 1 mm. [Water absorption capacity of modified polyalkylene oxide (g /
g)] 1 g of the weighed polyalkylene oxide-modified product was added to 200 ml of pure water, and the mixture was stirred for 24 hours.
The solution was filtered through a 0-mesh wire net, and the weight of the gel after the filtration was defined as water absorption capacity [g (pure water) / g (resin)]. (Hygroscopic) Using a knitted fabric obtained by knitting the obtained fiber into a tube,
This was dried at a temperature of 105 ° C. for 2 hours to measure its weight W0, and then conditioned at 25 ° C. and a relative humidity of 60% for 2 hours to measure its weight W1. Find the rate M0. Next, the sample was allowed to absorb moisture at a temperature of 34 ° C. and a relative humidity of 90% for 24 hours.
2 is measured, and the water content M1 is calculated by the following equation (b). Subsequently, the sample was subjected to a temperature of 25 ° C and a relative humidity of 60
%, The weight W3 is measured, and the moisture content M2 after dehumidification is calculated by the following equation (c). M0 (%) = [(W1-W0) / W0] × 100 (a) M1 (%) = [(W2-W0) / W0] × 100 (b) M2 (%) = [(W3-W0) ) / W0] × 100 (c) [Strength of elongation] Using an Autograph AGS-50D manufactured by Shimadzu Corporation, the measurement was performed at a sample length of 25 cm and a pulling speed of 25 cm / min. [Adhesive feeling at the time of moisture absorption] Using a knitted fabric obtained by knitting the obtained fibers into a tube, this sample was subjected to a temperature of 34 ° C and a relative humidity of 90%.
After 24 hours of moisture absorption, the stickiness due to the moisture absorption was evaluated by a three-stage tactile sensation (in order of no stickiness, ○, Δ, ×). [Quality of Fabric] Using a knitted product obtained by knitting the obtained fiber into a tube, the glossiness, light weight / bulkness, and texture of the knitted product were evaluated by visual and tactile evaluation on a three-point scale (in order of good to good, △, ×) ) Was done.

Examples 1 and 2 Nylon 6 pellets having a relative viscosity of 3.5 (measured at a concentration of 1 g / dl in 96% sulfuric acid as a solvent at a temperature of 25 ° C.)
Modified polyethylene oxide which is a reaction product of 5 parts by weight with polyethylene oxide, 1,4-butanediol and dicyclohexylmethane-4,4′-diisocyanate [“Aqua Coke” (manufactured by Sumitomo Seika Co., Ltd. (water absorption capacity 35 g)
/ G, melt viscosity: 4000 poise)] and a mixture obtained by dry blending with 15 parts by weight is referred to as polymer A.
The nylon 6 pellet No. 5 was used as polymer B. Example 1
In the above, the polymer A
In the second embodiment, a square portion is formed by polymer B, and a square portion is formed by polymer A so as to form the shape shown in FIG. The extruders were supplied to different extruders so as to form a sheath portion and a protruding portion, respectively, and were melt-spun from a composite spinneret. At this time, the spinning temperature is 270
C., melted and spun at a temperature of .degree. C., stretched between rollers, and wound at a speed of 3500 m / min to obtain a hollow composite fiber (66 dtex / 16f) having a well-shaped cross section as shown in FIGS.

Comparative Examples 1 and 2 The same procedure as in Example 1 was carried out except that the spinning temperature was variously changed so that the ratio of the protrusions in the cross section of the fiber and the bulkiness ratio were as shown in Table 1.

Comparative Example 3 The same procedure as in Example 1 was carried out except that the spinneret was changed and the cross-sectional shape of the fiber was changed to a round cross-sectional shape having no projection.

Comparative Example 4 The procedure of Example 1 was repeated except that the polymer forming the square portion was changed to Polymer B.

Table 1 shows measured values and evaluation results of the fibers obtained in Examples 1 and 2 and Comparative Examples 1 to 4.

[0032]

[Table 1]

As is clear from Table 1, the conjugate fibers of Examples 1 and 2 were excellent in moisture absorption / release properties and had sufficient strength and elongation characteristics equivalent to those of the reference examples. On the other hand, the fiber of Comparative Example 1 has a too low bulk ratio, the fiber of Comparative Example 2 has a too low ratio of protrusions, and the fiber of Comparative Example 3 has a round cross-sectional shape having no protrusions. As a result, the obtained fiber had low bulkiness and was inferior in texture, and its stickiness was also inferior as compared with the examples. The conjugate fiber of Comparative Example 4 was inferior in hygroscopicity because it did not contain a hygroscopic component.

[0034]

The conjugate fiber of the present invention, when knitted and woven, has excellent moisture absorption and desorption properties while maintaining high heat retention, has good touch and comfort, and is lightweight and has a unique texture and luster. Thus, a fabric having functions such as bulkiness and water repellency can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing one embodiment of a well-shaped hollow composite fiber of the present invention.

FIG. 2 is a schematic cross-sectional view showing another embodiment of the well-shaped hollow composite fiber of the present invention.

FIG. 3 is a schematic cross-sectional view showing a method for calculating a bulkiness rate of a well-shaped hollow composite fiber according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Core part 2 Hollow part 3 Sheath part 4 Projection part 5 Square part

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4L041 AA07 BA02 BA04 BA05 BA38 BA41 BC02 BD13 CA06 CA19 DD01 DD21 4L045 AA05 BA16 BA18 BA24 BA55

Claims (2)

[Claims] 1. A well-shaped cross-sectional shape which is formed from a thermoplastic polymer, has a quadrangular cross-sectional shape, and has two substantially perpendicular projections at each corner of a quadrangular portion having a hollow portion near the center. The hollow fiber presenting, wherein the proportion of the area of the protruding portion to the total area in the cross section of the fiber is 30% or more, the bulkiness is 20% or more, and the square portion has a polyalkylene oxide as a moisture absorbing and releasing component. A hollow composite fiber having a moisture-absorbing and releasing property, comprising a polyalkylene oxide-modified product obtained by reacting a polyalkylene oxide obtained by reacting a polyalkylene oxide with a polyol and an aliphatic isocyanate compound. 2. The hollow composite fiber according to claim 1, wherein the quadrangular portion has a core-in-sheath shape, and a polyalkylene oxide obtained by reacting a polyalkylene oxide with a polyol and an aliphatic isocyanate compound in the core. A well-shaped hollow composite fiber having moisture absorption and desorption properties, characterized by containing a modified product.