JPH09157960A - Conjugate fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a conjugate fiber excellent in lightweight feeling and providing a dyed article good in color development notwithstanding a solid fiber by conjugate spinning polymethylpentene as one component. SOLUTION: This conjugate fiber contains polymethlpentene as core component and polyethylene terephthalate or nylon 6 as sheath component and these components are sheath-core spun to afford a lightweight conjugate fiber having 60-90% of polymethylpentene core area ratio in cross-sectional view of the fiber, and the fiber density <=1.0g/cm<3> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite fiber which can give a lightweight feeling when formed into a woven or knitted product and a coloring property when dyed.

[0002]

2. Description of the Related Art Among synthetic fiber woven and knitted fabrics, which have made remarkable progress in recent years, a lightweight feeling is drawing attention as one of the new functionalities. As a means for embodying this, fibers using polyethylene and polypropylene, hollow sections Fibers can be mentioned, which have a certain reputation.

However, the former is difficult to dye,
Moreover, since it has a low melting point, it cannot be used as a fiber material for clothing because it cannot be processed into iron or the like. The latter, of course, has a hollow portion as compared with the solid fiber, so that if the outer diameter of the fiber section is the same, the hollow portion will be lighter by the hollow portion, and under the same fineness conditions, The flexural rigidity of the fiber and the solid fiber can be higher in the hollow fiber than in the solid fiber due to the difference in bending moment due to the cross-sectional shape. You can add level of elasticity and elasticity. However, in the hollow fiber, the hollow portion is crushed in the post-processes such as false twisting, knitting, and weaving, and the hollowness is significantly reduced, so that a sufficient lightweight feeling cannot be expressed. Further, there is a defect that the color developability is remarkably alienated due to the reflection of light on the boundary surface of the hollow portion, and only a whitish color can be dyed.

[0004]

In view of the above problems, the present inventors provide a fiber which is a solid fiber and is capable of imparting a dyed product having an excellent lightweight feeling and an excellent coloring property. The purpose is to

[0005]

Means for Solving the Problems The present invention for achieving the above object has the following constitution.

That is, a composite fiber containing polymethylpentene as one component, wherein the area ratio of polymethylpentene to the cross section of the composite fiber is 60 to 90% and the fiber density is 1.0 g / cm ³ or less. It is a composite fiber characterized by being present.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. First, the conjugate fiber of the present invention is characterized in that one component is composed of polymethylpentene. Polymethylpentene is a polymer obtained by polymerization of 4-methylpentene-1 and has a melting point of 220 to 245 ° C. Considering the spinnability as a fiber, the melt flow rate is preferably 1 to 100 g / 10 min. Such polymethylpentene may be a copolymer of another polymer or a blend of other polymers within a range that does not impair the polymer performance. Further, if necessary, within a range not impairing the present invention, an antioxidant, an ultraviolet absorber, a fluorescent whitening agent, a matting agent, an antistatic agent, a flame retardant, a flame retardant auxiliary agent,
Additives such as lubricants, colorants, plasticizers and inorganic fillers may be added.

Examples of the other component constituting the conjugate fiber of the present invention include polyesters and polyamides which are general-purpose resins. The polyester is preferably a polyester containing terephthalic acid as a main dicarboxylic acid component and at least one alkylene glycol selected from ethylene glycol, trimethylene glycol, and tetramethylene glycol as a main glycol component, and an object of the present invention. 3 within the range that does not impair
The components may be copolymerized.

The third component which can be copolymerized is isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, biphenyldicarboxylic acid, 4,4'-diphenyletherdicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,
4'-diphenyl sulfone dicarboxylic acid, 4,4'-diphenyl isopropylidene dicarboxylic acid, 1,2-diphenoxyethane-4 ', 4 "-dicarboxylic acid, anthracene dicarboxylic acid, 2,5-pyridinedicarboxylic acid, diphenoxy ketone Aromatic dicarboxylic acids such as dicarboxylic acid, 5-sodium sulfoisotalic acid, dimethyl 5-sodium sulfoisophthalate, 5-tetrabutylphosphonium sulfoisophthalic acid; malonic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, etc. Aliphatic dicarboxylic acids; alicyclic dicarboxylic acids such as decalin dicarboxylic acid and cyclohexanedicarboxylic acid; hydroxycarboxylic acids such as β-hydroxyethoxybenzoic acid, p-oxybenzoic acid, hydroxypropionic acid and hydroxyacrylic acid; Forming derivatives derived from carboxylic acids, such as ε over caprolactone aliphatic lactone,
Trimethylene glycol, tetramethylene glycol,
Hexamethylene glycol, neopentyl glycol,
Aliphatic diols such as diethylene glycol and polyethylene glycol; hydroquinone catechol, naphthalene diol, resorcin, bisphenol A, ethylene oxide adduct of bisphenol A, bisphenol S,
Aromatic diols such as ethylene oxide adducts of bisphenol S; aliphatic diols such as cyclohexanedimethanol can be mentioned. These 3rd components may be copolymerized by 1 type (s) or 2 or more types.

Further, the polyester includes polyvalent carboxylic acids such as trimellitic acid, trimesic acid, pyromellitic acid and tricarballylic acid within a range where the polyester is substantially linear; glycerin, trimethylolethane and trimethylol. A polyhydric alcohol such as propane or pentaerythritol may be contained.

In the present invention, a polyester in which 80 mol% or more of the repeating units are ethylene terephthalate units or butylene terephthalate units is preferable, and 5-sodium sulfo is preferable from the viewpoint of sharpness of color of the dyed product. Polyethylene terephthalate copolymerized with isophthalic acid or polybutylene terephthalate copolymerized with 5-sodium sulfoisophthalic acid is preferable. The copolymerization amount of 5-sodium sulfoisophthalic acid is preferably in the range of 1 to 10 mol%.

The above-mentioned polyester may be added to the above-mentioned polyester, if necessary, within a range not impairing the present invention.
Additives such as optical brighteners, matting agents, antistatic agents, flame retardants, flame retardant auxiliaries, lubricants, colorants, plasticizers and inorganic fillers may be added.

The above polyester preferably has an intrinsic viscosity [measured at 30 ° C. using a mixed solvent of phenol / tetrachloroethane (weight ratio 50/50)] in the range of 0.45 to 0.85. The intrinsic viscosity of the polyester is 0.
If it is less than 45, the strength of the obtained fiber will be low and it will not be practical. On the other hand, when the intrinsic viscosity of the polyester exceeds 0.85, the melt viscosity becomes too high,
The spinnability and spinnability are poor, which is not preferable.

Polyamide is nylon 6, nylon 6
6, polyamides such as nylon 610, nylon 12, nylon 11, nylon 4, nylon 46; semi-aromatic polyamides comprising aliphatic diamines and aromatic dicarboxylic acids. The third component may be copolymerized with these polyamides, or may contain a colorant such as a dye or a pigment, an additive such as a fluorescent whitening agent, a light resistance improver, and a heat resistance stabilizer. .

The degree of polymerization of the above-mentioned polyamide is about 22,000 or less in terms of number average molecular weight, especially 6000 to 20000,
Further, it is preferably 11,000 to 15,000. If the degree of polymerization is too high, the fluidity of the polymer will decrease, and a problem will occur in terms of spinnability. On the other hand, if the degree of polymerization is too low, there is a problem that the fiber-forming ability is significantly deteriorated. The above-mentioned semi-aromatic polyamide has 4 to 12 carbon atoms.
Is a polymer having an aliphatic diamine and an aromatic dicarboxylic acid such as terephthalic acid, isophthalic acid, xylene dicarboxylic acid and naphthalene dicarboxylic acid as main components, and a polymer having an intrinsic viscosity of 0.7 to 1.10. The intrinsic viscosity is a value measured in concentrated sulfuric acid at a concentration of 0.2 g / dl at 30 ° C.

In the composite fiber of the present invention, the composite ratio (cross-sectional area ratio) of polymethylpentene in the fiber cross section is
The cross-sectional area of polymethylpentene is A, and the cross-sectional area of the other component is B
Is the value indicated by A / (A + B), and the value is 6
It is preferably 0 to 90%, particularly preferably 70 to 85%. If the cross-sectional area ratio is less than 60%, the fiber density is 1.0
When a fiber having a g / cm ³ or less cannot be obtained, and when the cross-sectional area ratio exceeds 90%, a fiber having an excellent lightweight feeling is obtained, but the dyeing rate of polymethylpentene is low, so that the coloring property is obtained. It becomes difficult to obtain excellent fibers.

The cross-sectional area ratio can be obtained from a micrograph of the fiber cross-section, but it can also be set by adjusting the volume ratio of the discharge amounts of polymethylpentene and the other component during spinning.

The composite form of the composite fiber of the present invention is not particularly limited. A composite form having polymethylpentene as one component and having a fiber density of 1.0 g / cm ³ or less may be used, such as a concentric core-sheath type, an eccentric core-sheath type, a side-by-side type, and a multilayer laminated type. Can be adopted. Among them, the core-sheath type is preferable from the viewpoint of peeling resistance. For example, in the case of a core-sheath type composite fiber, the shape and number of cores are not particularly limited and can be selected according to the purpose. Further, the cross-sectional shape of the composite fiber is not particularly limited, and not only a round cross-section but also a polygonal cross-section such as a tri-octagon cross-section, a multi-lobal cross-section, a T-shape, a U-shape and the like can be selected.

In the conjugate fiber of the present invention, polymethylpentene and the polymer, which is the other component, are separately melted and introduced into the spin pack part, and a composite stream is formed by a usual method so as to take an arbitrary composite form. Spinning from the nozzle. In order to improve the spinnability, it is desirable that the melt viscosities of the polymethylpentene and the polymer which is the other component are almost equal. The spun filament yarn has a predetermined speed, for example, 10 to 6000.
Take up at m / min, refuel, and wind up in a package.
Next, the wound yarn is drawn in a usual manner so that the desired elongation and strength can be obtained. This drawing may be carried out continuously after the spun yarn is taken up and not wound up. Also 40
A method may be adopted in which the desired fiber physical properties are obtained all at once at a high speed of 00 m / min or more. For example, the fiber diameter is 100μ
When it exceeds m, it is desirable to spin at a low speed, cool the water bath, and then draw at a draw ratio of 3 to 6 times. The fiber diameter is 100
In the case of less than μm, it is desirable to spin at a speed of 1000 to 6000 m / min, and then to draw at a draw ratio of 60 to 90% of the cutting draw ratio, even if heat treatment is applied for the purpose of controlling the shrinkage ratio and the like. Good.

The obtained conjugate fiber is dyed with a disperse dye, a cationic dye, an acid dye or the like at any subsequent stage. When polyester is used as the polymer which is the other component, when dyeing with a disperse dye and / or a cationic dye, polyester is dyed by these dyes and polymethylpentene is hardly dyed. However, the dyed composite fiber can exhibit sufficient color developability because of the properties of polymethylpentene such as transparency and low refractive index. When polyamide is used as the other component polymer, dyeing with an acid dye stains the polyamide with the dye,
Almost no polymethylpentene is dyed. However, the dyed composite fiber can exhibit sufficient color development due to the properties of polymethylpentene such as transparency and low refractive index.

Usually, when light is incident on the composite fiber, the incident light is reflected, scattered, or refracted at the composite interface to enter the inside of the fiber. The light that has entered the inside of the fiber becomes colored light if the fiber is colored and comes out of the fiber again, but the reflected light is white light, and if the proportion of reflected light is large, the fiber is whitish. (Whitening phenomenon) and the depth of color is lost.

Generally, the reflectance r at the interface between two types of substances having different refractive indexes is shown by the following equation when the incident angle is 0. r = (n ₀ −n ₁ ) ² / (n ₀ + n ₁ ) ² (where n ₀ is the refractive index of the substance below the interface, and n ₁ is the refractive index of the substance above the interface)

Considering the case of a normal hollow fiber, the substance on the boundary surface is air, and the refractive index n ₁ is 1. Therefore, the greater the refractive index n _{0 of the} fiber, the greater the reflectance r and the poorer the color developability of the dyed product. Polyester has a refractive index of about 1.62 and polyamide has a refractive index of about 1.58, which is large among general-purpose fibers, and this is the main reason why the hollow fiber made of polyester or polyamide does not provide vivid color. Is considered to be.
On the other hand, in the conjugate fiber of the present invention, since n ₀ is 1.46 (refractive index of polymethylpentene), r is 0.
It becomes 0015 to 0.0028, and the reflection at the composite interface is extremely reduced, and a fiber having excellent color clarity and color development can be obtained.

The composite fiber of the present invention is a filament or a staple.
It is manufactured in the form of pull or the like and processed into the form of woven fabric, knitted fabric, non-woven fabric, or the like. After that, scouring, dyeing and, if necessary, resin processing are performed. Utilizing its excellent lightweight feel and color development of dyed products, sports clothing (baseball, tennis, soccer, table tennis uniforms, golf wear, triathlon, etc.), swimwear, women's outerwear. It is suitable for shoes, bags, supporters, socks and the like, and is also used for interiors such as carters, table cloths, carpets, tents, stuffed toys and the like.

[0025]

EXAMPLES The present invention will be described below in detail with reference to examples, but the present invention is not limited to these examples. The measured values in the examples are values calculated and calculated by the following method. (1) Melt viscosity of polymer (poise) It is a value at a shear rate of 1000 sec ⁻¹ when measured at 300 ° C. using Toyo Seiki Capillograph 1B type. (2) Melting point of polymer (° C.) This is an endothermic peak temperature determined by DSC of TA-3000 type manufactured by Metra Co. (3) Color developability (K / S) Spectral reflectance (R) of a product made of composite fiber is measured by a color analyzer (Hitachi 307 type, manufactured by Hitachi Ltd.),
It was determined from the following Kubelka-Munk equation. The larger this value is, the greater the color developability is. K / S = (1−R) ² / 2RR is the reflectance at the maximum absorption wavelength position of the visible reflectance curve of the product. (4) Saturation (%) It is a saturation value determined by JIS Z 8722 (a method for measuring an object color by a 2-degree visual field XYZ system). (5) False twistability Using a spindle false twisting device, the number of false twists is 2280 T / m, the false twist temperature is 180 ° C, and the condition of the false twisted yarn is visually observed at a speed of 100 m / min. It was evaluated by. ◯: No crushing of fiber cross section and no peeling of polymer-interface were observed. Δ: Although the fiber cross section was not crushed, some peeling at the polymer-interface was observed. X: The cross section of the fiber was severely crushed, and the shape before processing was not formed, or the peeling of the polymer-interface was severe.

Example 1 As a sheath component, melting point 256 ° C., intrinsic viscosity [η] = 0.7
Polyethylene terephthalate of 0, polymethylpentene having a melting point of 235 ° C. and a melt viscosity of 800 poise as a core component, and using a common core-sheath type composite nozzle, a temperature of 290 ° C., a spinning speed of 1000 m / min. Was subjected to composite spinning, followed by drawing 3.5 times at a residual heat roller temperature of 80 ° C. and a plate temperature of 120 ° C. to obtain a yarn of 75 denier / 24 filament. The cross-sectional area ratio of polymethylpentene was 75%. The fiber density is 0.97 g / cm ^3.
It was a very lightweight fiber that floated on water. A smooth-snit was created using the obtained yarn and dyed under the following conditions.

Dyeing conditions Disperse dye: Dispersol Brill Scarlet D-SF200 Grains 3% owf Dispersant: Diper-TL 1g / l pH adjuster: Acetic acid 0.5cc / l Bath ratio: 50: 1 Temperature: 130 ° C Time: 40 Minute reduction cleaning Hydrosulfide 1g / l Sodium hydroxide 1g / l Amylazine D (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 1g / l Bath ratio: 50: 1 Temperature: 80 ° C Time: 20 minutes

The color developability, saturation and the like of the composite fiber constituting the dyed product were evaluated and are shown in Table 1. The color developability is 4.5,
The saturation was 41%, indicating good dyeability. No bleaching phenomenon was observed. Further, when the composite fiber was subjected to false twisting, a good wooly yarn was obtained.

Comparative Example 1 Using polyethylene terephthalate having a melting point of 256 ° C. and an intrinsic viscosity [η] = 0.70, a hollow fiber nozzle spun at a spinning temperature of 295 ° C. and a speed of 1000 m / min.
Was drawn 3.3 times to produce a hollow fiber of 75 denier / 24 filament. The hollow ratio of the fiber is 30%, and the apparent fiber density considering the hollow is 0.97 g / c.
m ³ . Using this hollow fiber, knitting, processing and dyeing were carried out in the same manner as in Example 1 and evaluated. The color developability was 2.5 and the saturation was 5%. The hue was whitish and poor in color development. Further, when this hollow fiber was subjected to false twisting, the hollow part of the fiber was almost crushed, and a lightweight feeling could not be imparted.

Example 2 2.5 mol% of 5-sodium sulfoisophthalic acid copolymerized as a core component, melting point 248 ° C., intrinsic viscosity [η]
= 0.52 polyethylene terephthalate, polymethylpentene as the sheath component, and the composite ratio is 8
The content was adjusted to 3%, and spinning and drawing were performed in the same manner as in Example 1.
The density of the obtained fiber was 0.93 g / cm ³ .
Then, a smooth-knit was prepared and dyed under the following conditions. Table 1 shows the results.

Dyeing conditions Cationic dye: Cathilon Brill Red 4GH200 2% owf Auxiliary agent: Sodium sulfate 2 g / l Acetic acid 1% owf Sodium acetate 0.5% owf Bath ratio: 50: 1 Temperature: 120 ° C. Time: 40 minutes reduction washing Hydrosulfide 1 g / l Ammonia water 1 g / l Amylazine D (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) 1 g / l Bath ratio: 50: 1 Temperature: 70 ° C. Time: 20 minutes When the composite fiber was further twisted, A good wooly yarn was obtained.

Comparative Example 2 and Comparative Example 3 The composite fiber was spun in the same manner as in Example 1 except that the composite ratio of polymethylpentene was changed as shown in Table 1, followed by knitting, processing and dyeing. Performed and evaluated.
Table 1 shows the results. In the yarn obtained in Comparative Example 2, peeling of the sheath was observed in the drawing process, and peeling of the sheath was remarkable in the false twisting process. The yarn obtained in Comparative Example 3 had no problem in fiber performance, but had a large fiber density of 1.22 g / cm ³ and did not satisfy the intended lightweight feel.

Example 3 Composite spinning and drawing were carried out in the same manner as in Example 1 except that nylon 6 having an intrinsic viscosity of 0.9 was used as the sheath component. The density of the obtained fiber was 0.94 g / cm ³ . Moreover, when the false twisting process is applied to the composite fiber, a good wool is obtained.
Lee yarn was obtained.

[0034]

[Table 1]

[0035]

EFFECTS OF THE INVENTION According to the present invention, it is possible to obtain a fiber which is a solid fiber and which can impart a dyed product excellent in light weight feeling and excellent in color developability.

Claims (1)

[Claims] 1. A composite fiber comprising polymethylpentene as a component, wherein the area ratio of polymethylpentene in the cross section of the composite fiber is 60 to 90%, and the fiber density is 1.0 g.
/ Cm ³ or less, a composite fiber.