JP2008223164A - Conjugated fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conjugated fiber having improved fiberizing process properties, physical properties and dyeability without deteriorating characteristics essentially possessed by an ethylene-vinyl alcohol-based copolymer. <P>SOLUTION: The conjugated fiber is composed of a mixed resin component (components B+C) composed of a mixture of a semi-aromatic polyamide (component B) and an aliphatic polyamide (component C) and the ethylene-vinyl alcohol-based copolymer component (component A) having 25-60 mol% of ethylene content. The ethylene-vinyl alcohol-based copolymer component (component A) occupies at least a part of the conjugated fiber surface. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a composite fiber having an ethylene-vinyl alcohol copolymer as one component, good fiberizing process properties, excellent alkali resistance / peeling resistance, and excellent dyeability.

Conventionally, synthetic fibers, for example, fibers such as polyester, nylon 6, and polyamides such as nylon 66 have excellent physical and chemical properties, and are widely used not only for clothing but also for industrial use. Industrially valuable value.
However, since these synthetic fibers are low in moisture absorption and water absorption, the actual situation is that entry into fields requiring moisture absorption and water absorption such as underwear, pants, sheets and towels is limited.
For example, in the case of polyester fibers, various proposals have been made for improving moisture absorption and water absorption, which can be said to be the greatest defect. Specifically, a method of post-treating polyester fibers with a hydrophilic post-processing agent, a method of imparting moisture absorption and water absorption by making the polyester fiber surface or fiber interior porous, and the like have been proposed.

  However, all of these methods have a problem that moisture absorption and water absorption are insufficient, or performance imparted by washing deteriorates. In recent years, in order to improve these problems, an ethylene-vinyl alcohol copolymer, which is a resin having excellent hydrophilicity, is combined with other thermoplastic polymers such as polyester, polyamide, polyolefin, etc., and made into fibers. Various proposals have been made to improve moisture absorption and water absorption (Japanese Patent Publication No. 56-5846, Japanese Patent Publication No. 55-1372, Japanese Patent Publication No. 7-84681, etc.).

  However, in the case where the other components to be combined are polyester and polyolefin, there are problems such as deterioration in processability and deterioration in quality due to poor compatibility, and the use is limited. In the case of polyamide, the compatibility is good, but in the case of ordinary polyamide (for example, aliphatic polyamide such as nylon-6, nylon-66, etc.) Applications to applications were limited. In addition, ordinary polyamide has a glass transition temperature near room temperature, so that physical properties are easily changed, and there is a problem in practical use.

  The present inventors have overcome the above-mentioned problems of the prior art and have improved the adhesiveness and dyeability between components without impairing the characteristics inherent to the ethylene-vinyl alcohol copolymer. Has proposed a composite spun fiber comprising a semi-aromatic polyamide and an ethylene-vinyl alcohol copolymer (Japanese Patent Laid-Open No. 2005-248344). However, this fiber still has a defect that the fiberizing process property, physical properties and dyeability are insufficient.

Japanese Patent Publication No.56-5846 Japanese Patent Publication No.55-1372 Japanese Examined Patent Publication No. 7-84681 JP-A-2005-248344

  The present invention overcomes the above-mentioned problems and does not impair the characteristics inherent to the ethylene-vinyl alcohol copolymer, and thus is more suitable for fiberization than the fiber obtained by the invention of the above-mentioned JP-A-2005-248344. An object of the present invention is to provide a composite fiber having improved processability, physical properties and dyeability.

That is, the present invention relates to a mixed resin component (B + C component) composed of a mixture of semi-aromatic polyamide (B), aliphatic polyamide and (C), and an ethylene-vinyl alcohol system having an ethylene content of 25 to 60 mol%. A composite fiber comprising a copolymer component (component A), wherein the ethylene-vinyl alcohol copolymer component (component A) occupies at least a part of the composite fiber surface. Preferably, the semi-aromatic polyamide (B) constituting the mixed resin component (B + C component) is composed of a dicarboxylic acid unit and a diamine unit, and 60 to 100 mol% of the dicarboxylic acid unit is an aromatic dicarboxylic acid unit, 60-100 mol% of the diamine units are aliphatic diamine units, and the mass ratio of the semi-aromatic polyamide (B) and the aliphatic polyamide (C) constituting the mixed resin component (B + C component) is 70: 30-97. : In the case of the above composite fiber in the range of 3.
More preferably, when the aromatic dicarboxylic acid unit is a terephthalic acid unit and the aliphatic diamine unit is a 1,9-nonanediamine unit, more preferably, the aromatic dicarboxylic acid unit is a terephthalic acid unit, The unit consists of a 1,9-nonanediamine unit and a 2-methyl-1,8-octanediamine unit, and the molar ratio of the 1,9-nonanediamine unit to the 2-methyl-1,8-octanediamine unit is from 40:60. This is the case in the range of 99: 1.
Moreover, in this invention, the case where the composite ratio (mass ratio) of a mixed resin component (B + C component) and an ethylene-vinyl alcohol-type copolymer component (A component) is 30: 70-90: 10 is mentioned as a suitable example. It is done. A preferred example is a case where the composite form is a sea-island type, the sea component is the ethylene-vinyl alcohol copolymer component (A component), and the island component is the mixed resin component (B + C component). .

  The ethylene-vinyl alcohol copolymer (A) according to the present invention is a saponified polymer of an ethylene-vinyl acetate copolymer. The amount of ethylene units constituting the polymer (A) (referred to as ethylene content) is preferably 25 to 60 mol%, more preferably 30 to 55 mol%. If the ethylene content of the copolymer (A) is higher than 60 mol%, that is, the proportion of vinyl alcohol units is reduced, the melting point of the resulting polymer is lowered, and the cross-linking acetalization described later can be performed. In some cases, a product having satisfactory hot water resistance cannot be obtained. On the other hand, when the ethylene content exceeds 60 mol%, the properties such as hydrophilicity are lowered due to the reduction of hydroxyl groups, and it is difficult to obtain the desired natural fiber-like texture with hydrophilicity. On the other hand, from the viewpoint of the fiber structure, if the proportion of vinyl alcohol units exceeds 75% and becomes too high, melt spinnability is lowered, and single yarn breakage and yarn breakage increase during spinning or drawing.

  In particular, in the present invention, in order to complex-spin the ethylene-vinyl alcohol copolymer (A) with the high melting point semi-aromatic polyamide (B), it is usually necessary to set the spinning temperature to 250 ° C. or higher. If the proportion of vinyl alcohol units in the copolymer (A) increases, the melting point peak by differential scanning calorimetry (DSC) shifts to the high temperature side, and it is possible to perform composite spinning with semi-aromatic polyamide (B) However, on the other hand, since the ethylene content is small, melt spinnability tends to decrease. Therefore, in consideration of the composite spinning with a high melting point polymer such as semi-aromatic polyamide, it is preferable to use an ethylene-vinyl alcohol copolymer having an ethylene content of 30 to 60 mol%.

  The semi-aromatic polyamide (component B), which is the other component used in the conjugate fiber of the present invention, substantially consists of a dicarboxylic acid unit and a diamine unit, and has various physical properties such as alkali resistance, acid resistance and strength. Any one of these units is mainly composed of an aromatic compound. Preferably, 60 to 100 mol% of the dicarboxylic acid unit is composed of an aromatic dicarboxylic acid unit, more preferably 60 mol% or more, more preferably 75 mol% or more of the terephthalic acid unit as the aromatic dicarboxylic acid unit. In particular, a case where the content is 90 mol% or more is preferable. When neither the dicarboxylic acid unit nor the diamine unit is mainly composed of an aromatic compound, various physical properties such as alkali resistance, acid resistance and strength of the resulting fiber are lowered.

Examples of other dicarboxylic acid units other than the terephthalic acid unit include, for example, malonic acid, dimethylmalonic acid, succinic acid, 3,3-diethylsuccinic acid, glutaric acid, 2,2-dimethylglutaric acid, adipic acid, and 2-methyl. Aliphatic dicarboxylic acids such as adipic acid, trimethyladipic acid, pimelic acid, azelaic acid, sebacic acid and suberic acid; alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; isophthalic acid Acid, 2,6-naphthacyne dicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,4-phenylenedioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, 4,4'-oxydibenzoic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone 4,4'-dicarboxylic acid, a unit derived from an aromatic dicarboxylic acid such as 4,4-biphenyl dicarboxylic acid can be included alone or in combination. From the viewpoint of chemical resistance, heat resistance, etc., among the dicarboxylic acid units described above, it is preferable to include an aromatic dicarboxylic acid unit other than terephthalic acid.
Furthermore, a polyvalent carboxylic acid having three or more functional groups such as trimellitic acid, trimesic acid, and pyromellitic acid may be included within a range where fiberization is possible.

  As a diamine unit, the case where it contains 60 mol%-100 mol% of an aliphatic diamine unit is preferable, the case where 75 mol% or more is contained is more preferable, and the case where it contains 90 mol% or more is especially preferable . When the content of the aliphatic diamine unit is less than 60 mol%, the acid resistance, strength, etc. of the resulting fiber are lowered.

  Specific examples of the most preferred diamine unit include 1,9-nonanediamine. Examples of diamine units other than the 1,9-nonanediamine unit include ethylenediamine, propylenediamine, 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,10-decanediamine, 1,12-dodecanediamine, 2-methyl-1,5-pentanediamine, 3-methyl-1,5-pentanediamine, 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 2-methyl-1,8-octanediamine, 5-methyl-1,9-nonanediamine Aliphatic diamines such as: cyclohexanediamine, methylcyclohexanediamine, isophorone diamine Such as p-phenylenediamine, m-phenylenediamine, xylylenediamine, xylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenylether, etc. One or more units derived from an aromatic diamine can be included.

  When other diamine units other than 1,9-nonanediamine unit are contained, for example, considering use in applications requiring heat resistance, hydrolysis resistance, chemical resistance, etc., such as battery separators, It is preferable to introduce a 2-methyl-1,8-octanediamine unit as the diamine unit.

  When the diamine unit contains a 1,9-nonanediamine unit and a 2-methyl-1,8-octanediamine unit, 60 to 100 mol% of the diamine unit is a 1,9-nonanediamine unit and 2-methyl- It is preferably composed of 1,8-octanediamine units, and the molar ratio of 1,9-nonanediamine units to 2-methyl-1,8-octanediamine units is preferably 40:60 to 99: 1, and 70:30 to More preferably, the ratio is 95: 5.

  The production method of the semi-aromatic polyamide (B) is not particularly limited, and any production method known as a method for producing a crystalline polyamide can be used. For example, it can be polymerized by a method such as a solution polymerization method or an interfacial polymerization method using acid chloride and diamine as raw materials, a melt polymerization method using dicarboxylic acid and diamine as raw materials, a solid phase polymerization method, or a melt extruder polymerization method.

  The logarithmic viscosity of the semi-aromatic polyamide (B) used in the present invention is preferably in the range of 0.4 to 2.0 when measured by the method described later, and pelletization cannot be carried out if it is less than 0.4. Polymers having a value larger than 2.0 are difficult to polymerize. Preferably, it is in the range of 0.6 to 1.4, more preferably in the range of 0.7 to 1.2 in terms of fiber physical properties and fiberizing process properties.

  Further, as the aliphatic polyamide (C) used in the present invention, for example, polycaproamide (nylon-6), poly-ω-aminoheptanoic acid (nylon-7), polyundecanamide (nylon-11), polylaurin Lactam (nylon-12), polyethylenediamine adipamide (nylon-2,6) polytetramethylene adipamide (nylon-4,6), polyhexamethylene adipamide (nylon-6,6), polyhexamethylene Sebacamide (Nylon-6,10), Polyhexamethylene dodecamide (Nylon-6,12), Polyoctamethylene adipamide (Nylon-8,6), Polydecanomethylene adipamide (Nylon-10, 6), polydodecamethylene sebacamide (nylon-10,8), or caprolactam / laurinlac Copolymer (nylon-6 / 12), caprolactam / ω-aminononanoic acid copolymer (nylon-6 / 9), caprolactam / hexamethylene adipate copolymer (nylon-6 / 6,6), lauric lactam / Hexamethylenediamine adipate copolymer (nylon-12 / 6,6), hexamethylenediamine adipate / hexamethylenediamine sebacate copolymer (nylon-6,6 / 6,10), ethylenediamine adipate / hexamethylenediamine adipate Examples thereof include a polymer (nylon-2,6 / 6,6), caprolactam / hexamethylenediamine adipate / hexamethylenediamine sebacate copolymer (nylon-6,6 / 6,10), and the like.

  Among these polyamides, those preferred according to the present invention include nylon-6, nylon-6,6 and nylon-6 / 12. Among these, nylon-6 is most preferable.

  In the present invention, the fiber process stability is that the aliphatic polyamide (C) is mixed in a mass ratio of 3 to 30% with respect to the total amount of the semi-aromatic polyamide (B) and the aliphatic polyamide (C). It is preferable for improving the strength improvement and dyeability. More preferably, it is 5 to 25%. If the mixing ratio is less than 3%, the fiber process stabilization effect, the strength improvement effect, and the dyeability improvement effect cannot be obtained. On the other hand, if it is higher than 30%, the fiberization processability deteriorates and the color fastness decreases, which is not preferable.

  The ethylene-vinyl alcohol copolymer (component A) and the mixture of semi-aromatic polyamide (B) and aliphatic polyamide (C) (B + C component) used in the present invention are antistatic agents and matting agents such as titanium dioxide. In addition, a heat-stable antioxidant may be added.

  Further, the composite ratio of the ethylene-vinyl alcohol copolymer (component A) and the mixture of semi-aromatic polyamide (B) and aliphatic polyamide (C) (component B + C) in the case of a composite fiber is the former: latter (Mass ratio) = 30: 70 to 90:10 is preferable, and the composite ratio of the two can be adjusted within the above range depending on the composite form and fiber shape. When the composite ratio of the ethylene-vinyl alcohol copolymer (component A) is less than 30% by mass, that is, the mixture of the semi-aromatic polyamide (B) and the aliphatic polyamide (C) (B + C component) exceeds 70% by mass. In this case, moisture absorption and water absorption performance are insufficient, and a soft texture cannot be obtained. On the other hand, when the composite ratio of the ethylene-vinyl alcohol copolymer (component A) exceeds 90% by mass, that is, the mixture of the semi-aromatic polyamide (B) and the aliphatic polyamide (C) (B + C component) is 10% by mass. If it is less than 1, the fiber strength is insufficient, and the color developability due to dyeing is insufficient.

The composite form is not particularly limited as long as it is a conventionally known composite form, for example, as shown in FIGS. 1A to 1E. However, the hydrophilicity of the ethylene-vinyl alcohol copolymer (component A) and wind In order to exhibit improvement properties, it is necessary to occupy at least a part of the surface of the composite fiber, and preferably 30% or more of the surface is an ethylene-vinyl alcohol copolymer (component A). Is the case.
Specific examples of the composite form include a sea-island type having an ethylene-vinyl alcohol copolymer (component A) as a sea component, and a concentric or eccentric core having an ethylene-vinyl alcohol copolymer (component A) as a sheath component. Sheath type, ethylene-vinyl alcohol copolymer (component A), bimetallic type in which a mixture of semi-aromatic polyamide and aliphatic polyamide (component B + C) is bonded side by side, ethylene-vinyl alcohol copolymer (A Component layer) and a multilayer laminate type in which a plurality of layers comprising a mixture of semi-aromatic polyamide and aliphatic polyamide (B + C component) are alternately laminated. Among these, the sea-island type is ethylene-vinyl alcohol. This is most preferable because the characteristics of the system copolymer (component A) can be fully utilized.
The cross-sectional shape of the composite fiber may be a round cross section or an elliptical cross section, or may be an irregular cross section such as a triangle, a polygon, or a flat shape.

Next, a method for producing the composite fiber of the present invention will be described.
In the method for producing a composite fiber of the present invention, an ethylene-vinyl alcohol copolymer (component A) and a mixture of a thermoplastic polyamide (B) and a polyamide resin (C) (component B + C) are first used in separate extruders. Melt extrusion is carried out via a spinneret that is introduced into each spinning head and forms the desired individual composite shape. In this case, the melt spinning temperature, the melt spinning speed, etc. are not particularly limited, but the melt spinning temperature is set to (Tm + about) with respect to the melting point Tm (° C.) of the polymer having a higher melting point among the composite spinning polymers. 20 ° C. to Tm + about 40 ° C.) and a melt spinning speed (melt spinning amount) of about 20 to 50 g / spinning hole 1 mm ² min. Since it can be obtained by spinning process property, it is preferable.

Also, the size and number of spinning holes in the spinneret, the shape of the spinning hole, etc. are not particularly limited and can be adjusted according to the single fiber fineness, total denier, cross-sectional shape, etc. of the target composite fiber. The size of the hole (single hole) is preferably about 0.018 to 0.07 mm ² . If nozzle dirt accumulates around the hole in the spinneret and thread breakage occurs, use a method in which the nozzle hole outlet is tapered and the atmosphere under the nozzle is steam sealed to shut off oxygen. Is preferred.

  Then, the composite fiber melt-spun by the above is once cooled to a temperature not higher than the glass transition temperature of the polymer having a low glass transition temperature, preferably 10 ° C. or lower than the glass transition temperature. The cooling method or cooling device in this case is not particularly limited as long as it is a method or device that can cool the spun composite fiber below its glass transition temperature, but a cooling air blowing tube or the like under the spinneret. It is preferable to provide a cooling air blowing device and to cool the glass fiber below the glass transition temperature by blowing cooling air to the spun composite fiber.

  At that time, the cooling conditions such as the temperature and humidity of the cooling air, the blowing speed of the cooling air, and the cooling air blowing angle with respect to the spun fiber are not particularly limited, and the composite fiber spun from the base is swayed in the fiber. Any conditions may be used as long as they can be promptly and uniformly cooled to below the glass transition temperature while preventing them from occurring.

  Especially, the cooling air temperature is about 20 to 30 ° C., the cooling air humidity is about 20 to 60%, and the cooling air blowing speed is about 0.4 to 1.0 m / sec. It is preferable to cool the conjugate fiber spun with the direction perpendicular to the spinning direction because a high-quality conjugate fiber can be obtained smoothly. In addition, when cooling is performed under the above-described conditions using a cooling air blowing cylinder, a cooling air blowing cylinder having a length of about 80 to 160 cm with a slight gap or no gap immediately below the spinneret. Is preferably arranged.

  In addition, the take-up speed differs depending on whether the winding process is performed once after winding, when the film is spun and stretched in one step of direct spinning, or when it is wound as it is at a high speed without being stretched. It can be picked up in the range of min to 7000 m / min. If it is less than 500 m / min, spinning is not possible but it is inferior in productivity. On the other hand, at an ultra-high speed exceeding 7000 m / min, fiber breakage tends to occur. From the viewpoint of productivity and production cost, it is preferable to fiberize by a direct spinning drawing method.

In the present invention, the spun composite fiber is drawn, and the draw ratio is preferably 2 to 5 times and 60 to 85% of the breaking elongation.
Thus, the thickness of the composite fiber obtained by extending | stretching has the preferable range of 0.5-5 dtex for clothing use, and 0.5-30 dtex is preferable for the industrial material field | area.
The fibers thus obtained can be used as multifilament yarns or cut and used as staple fibers. When used as multifilament yarns, the total denier is generally 30 to 200 dtex. Is.

In addition, the fiber of this invention is dye | stained as needed. In addition, it is also possible to make an original fiber by adding a dye or a pigment to the polymer constituting the composite fiber. Furthermore, if necessary, various additives and stabilizers are added to the polymer constituting the fiber of the present invention, and various oils and surface treatment agents are added to the fiber surface, and various surface treatments are performed. It is also possible to perform the method and add the necessary properties.
If necessary, the fibers of the present invention are dyed. A typical example of a dye used for dyeing is a disperse dye.

  The conjugate fiber obtained in the present invention is processed into a fabric such as a woven fabric, a knitted fabric, and a non-woven fabric, and has high moisture absorption and water absorption. Therefore, moisture absorption and water absorption of underwear, pants, sheets, towels, handkerchiefs, pajamas, etc. are required. Used in the field. It can also be used in the field of industrial materials such as battery separators and filters.

  The fiber of the present invention is excellent in moisture absorption and water absorption, further excellent in dimensional stability under hot water conditions, further excellent in dyeability and peel resistance, and in terms of fiber physical properties. It can be used not only for applications but also in the field of industrial materials.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited at all by these Examples. In addition, the measured value in an Example is measured with the following method.

[Logarithmic viscosity of polyamide]
Calculated from the value measured using an Ubbelohde viscometer in a constant temperature bath at 30 ° C. using concentrated sulfuric acid.
[Fiber strength and elongation]
Measured according to JISL1013.

[Fiberification process properties]
Evaluated based on the occurrence of fluff and breakage when spinning 2000kg of composite fiber.
○: Good without fluff and breakage △: No breakage, slight occurrence of fluff x: Breakage occurs once or more

[Dyeability]
Sensory evaluation was performed by 10 panelists on the color developability when the tube knitting was dyed under the following conditions. The results were scored as 2 excellent points, 1 excellent point, and 0 inferior point, and the overall score was divided into 3 levels.
○: Total score is 15 points or more △: Total score is 6-14 points ×: Total score is 5 points or less

[Cylinder knitting processing conditions]
(Preprocessing)
Bisethylenedioxynonane 15% omf
Maleic acid 1g / l
Anionic activator 1g / l
90 ° C x 30 minutes (dyeing)
Diamix Navy Blue SPHconc 3% omf
Dispersant 1g / l
Acetic acid (50%) 1 g / l
Bath ratio 1:50 115 ° C x 40 min (reduction cleaning)
Hydrosulfite 1g / l
Sodium hydroxide 1g / l
Amiradine D (Daiichi Kogyo Seiyaku Co., Ltd.) 1g / l
80 ° C x 20 minutes [Liquid contamination]
The fastness of dyeing due to liquid contamination of the tubular knitted fabric treated under the above conditions was examined by the JISL-0844 A-2 method.

[Adhesiveness of each component of composite fiber]
24 to 48 filaments were twisted at 1500 T / M, the yarn was cut as it was, and the peeled state of the filaments on the cut surface was observed. The 10 cut locations were evaluated according to the following criteria.
○: When the degree of peeling is less than 10% Δ: When the degree of peeling is 1-30% x: When the degree of peeling exceeds 30%

  The production methods of semi-aromatic polyamide used in Examples and Comparative Examples are shown in the following reference examples.

Reference Examples 1-2
The amounts of terephthalic acid, 1,9-nonanediamine, 2-methyl-1,8-octanediamine, benzoic acid, sodium hypophosphite-hydrate (0.1% by mass relative to the raw materials) shown in Table 1 and Distilled water (2.2 liters) was added to an autoclave having an internal volume of 20 liters, and nitrogen substitution was performed. Subsequently, the mixture was stirred at 100 ° C. for 30 minutes, and the internal temperature was raised to 210 ° C. over 2 hours. At this time, the pressure of the autoclave was increased to 2.2 × 10 ⁶ Pa. The reaction was continued for 1 hour as it was, and then the temperature was raised to 230 ° C., and then kept at 230 ° C. for 2 hours. The reaction was continued while gradually removing water vapor and maintaining the pressure at 2.2 × 10 ⁶ Pa. Next, the pressure was reduced to 9.8 × 10 ⁵ Pa over 30 minutes, and the reaction was further continued for 1 hour to obtain a prepolymer. The prepolymer was dried at 100 ° C. under reduced pressure for 12 hours and pulverized to a size of 2 mm or less.
The pulverized product was subjected to solid phase polymerization at 230 ° C. and 1.3 × 10 Pa for 10 hours to obtain a polymer. The logarithmic viscosity of the obtained polymer is shown in Table 1.

Example 1
The semiaromatic polyamide (PA9MT) of Reference Example 2 shown in Table 1 is used as the semiaromatic polyamide (B) of the mixed resin component constituting the composite fiber, and nylon 6 (Ube Industries) is used as the aliphatic polyamide (C). Company: UBE nylon 6, intrinsic viscosity 1.4), blended with PA9MT / nylon 6 = 85/15, and the other composite component (A) is ethylene-vinyl alcohol having an ethylene content of 44 mol% A system copolymer was used. These semi-aromatic polyamide-aliphatic polyamide mixture (B + C component) and ethylene-vinyl alcohol copolymer (component A) are individually melt-extruded, and the ethylene-vinyl alcohol copolymer (component A) is sea, half A mixture of aromatic polyamide (B) and aliphatic polyamide (C) (B + C component) is used as an island and supplied to a spinning head that forms a cross-section of a sea island with 12 islands. Melt spinning was performed at a spinning temperature of 290 ° C. from a 24-hole round hole nozzle having a length of 0.5 mm and a nozzle hole outlet extending in a trumpet shape and an outlet diameter of 0.5 mmφ (see Table 2).

  A horizontal blowing type cooling air spraying device having a length of 1.0 m is installed immediately below the spinneret, and the composite fiber spun from the base is immediately introduced into the cooling air spraying device, at a temperature of 25 ° C. and a humidity of 65 RH%. The cooling air adjusted to was blown onto the spun fiber at a speed of 0.5 m / sec, and the fiber was cooled to 60 ° C. or less (the temperature of the fiber at the outlet of the cooling air blowing device = 40 ° C.).

The discharged spinning yarn of the composite fiber is taken up at 1000 m / min, continuously stretched without wringing, stretched 3.5 times with heat setting at 150 ° C., and 84 decitex / 24 filament at 3500 m / min. The drawn composite fiber was collected. Table 2 shows the physical properties, dyeability, adhesiveness, spinning processability, and dyeing fastness of the obtained fibers.
As is clear from the results in Table 2, the product of Example 1 was excellent in all of the fiber forming processability, dyeability, adhesiveness, and fiber physical properties.

Examples 2-4
Example 2 was carried out in the same manner as Example 1 except that the composite ratio of the A component and the B component was changed. Examples 3 and 4 were carried out in the same manner as Example 1 except that the C component aliphatic polyamide resin was changed.
As is clear from the results of Table 2, all of Examples 2 to 4 were excellent in all of the fiber forming processability, dyeability, adhesiveness, and fiber physical properties.

Examples 5-6
In Example 5, the ratio of the B component semi-aromatic polyamide to the C component aliphatic polyamide was changed. In Example 6, the semi-aromatic polyamide of Reference Example 1 shown in Table 2 was used. The same procedure as in Example 1 was carried out except that the ratio of the aromatic polyamide to the C component aliphatic polyamide was changed.
As is clear from the results of Table 2, all of Examples 5 to 6 were excellent in all of the fiber forming processability, dyeability, adhesiveness, and fiber physical properties.

Example 7
The same procedure as in Example 1 was performed except that the proportion of ethylene copolymerization of component A was changed as shown in Table 2 and the cross-sectional shape of the fiber was changed to that shown in FIG.
As is clear from the results in Table 2, the product of Example 7 was excellent in fiber forming processability, dyeability, adhesiveness, and fiber physical properties.

Comparative Examples 1-2
Comparative Example 1 is an example carried out in the same manner as Example 1 except that C component aliphatic polyamide was not used. Comparative Example 2 is the result when the same procedure as in Example 1 was performed except that the total amount of C component aliphatic polyamide was used without using B component semi-aromatic polyamide.
As is apparent from Table 2, Comparative Example 1 was inferior in adhesiveness, color developability and fiber forming processability as compared with the above Examples. On the other hand, although the thing of the comparative example 2 had no problem in color developability and adhesiveness, it was inferior to the fiber formation process property and physical property, and the point of liquid contamination was far inferior to the thing of the said Example.

It is a fiber section schematic diagram showing the example of the composite form of the present invention.

Explanation of symbols

A: ethylene vinyl alcohol copolymer component B + C: mixed component of semi-aromatic polyamide and aliphatic polyamide

Claims (6)

A mixed resin component (B + C component) comprising a mixture of a semi-aromatic polyamide (B) and an aliphatic polyamide (C), and an ethylene-vinyl alcohol copolymer component (A) having an ethylene content of 25 to 60 mol% Component), and the ethylene-vinyl alcohol copolymer component (component A) occupies at least a part of the surface of the composite fiber. The semi-aromatic polyamide (B) constituting the mixed resin component (B + C component) is composed of a dicarboxylic acid unit and a diamine unit, 60 to 100 mol% of the dicarboxylic acid unit is an aromatic dicarboxylic acid unit, and 60 to 60 diamine units. 100 mol% is an aliphatic diamine unit, and the mass ratio of the semi-aromatic polyamide (B) and the aliphatic polyamide (C) constituting the mixed resin component (B + C component) is in the range of 70:30 to 97: 3. The composite fiber according to claim 1. The composite fiber according to claim 2, wherein the aromatic dicarboxylic acid unit is a terephthalic acid unit and the aliphatic diamine unit is a 1,9-nonanediamine unit. The aromatic dicarboxylic acid unit is a terephthalic acid unit, the aliphatic diamine unit is composed of a 1,9-nonanediamine unit and a 2-methyl-1,8-octanediamine unit, and a 1,9-nonanediamine unit: 2-methyl- The composite fiber according to claim 2 or 3, wherein the molar ratio of 1,8-octanediamine units is in the range of 40:60 to 99: 1. The composite fiber according to claim 1, wherein a composite ratio (mass ratio) of the mixed resin component (B + C component) and the ethylene-vinyl alcohol copolymer component (A component) is 30:70 to 90:10. The composite fiber according to claim 1, wherein the composite form is a sea-island type, the sea component is an ethylene-vinyl alcohol copolymer component (A component), and the island component is a mixed resin component (B + C component).

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