KR20160143634A - Composite fiber, false twisted yarn formed from same, method for producing said false twisted yarn, and fabric - Google Patents

Abstract

A polyester conjugated fiber for friction-fusible foaming, which has excellent friction resistance and excellent processability and dyeability, is provided. A composite fiber comprising a core part and a sheath part which completely covers the core part, wherein the polymer of the core part is a polymer alloy comprising two or more kinds of thermoplastic polymers, the polymer alloy is composed of a polyester, a polyolefin and a compatibilizing agent, Wherein the polyester is a polyester, the island-like polyolefin has a sea-island structure, and the sheath is a polyester.

Description

TECHNICAL FIELD [0001] The present invention relates to a composite fiber, a method for manufacturing the same,

TECHNICAL FIELD The present invention relates to a composite fiber excellent in resistance to friction and abrasion, a method of manufacturing the same, and a fabric.

BACKGROUND OF THE INVENTION Polyester fibers are widely used in the sports medical field due to their excellent mechanical properties and chemical properties. However, unlike natural fibers such as cotton and rayon, synthetic fibers such as polyester have drawbacks in that, when sliding on a gymnasium or the like, the fabric is fused by frictional heat generated between the floor and the fabric, and holes are formed in the fabric.

Numerous proposals have been made so far to solve these problems.

For example, in Patent Documents 1 and 2, a method of mixing natural fibers such as rayon or heat-resistant fibers can be used. In Patent Document 3, a method of adding a smoothing agent such as silicone or polyethylene wax in post-processing has been proposed .

As a method for improving the polyester fiber itself, a method using a composite fiber in which a low-melting-point polymer having a melting point lower than that of the polyester is disposed in the core portion of the polyester fiber is proposed in Patent Documents 4 and 5, The melting heat of the polyester is absorbed by absorbing the frictional heat generated by the melting of the low melting point polymer of the core portion by the endothermic action before the polyester is melted. Therefore, when the frictional heat is released, the low-melting-point polymer of the core portion is solidified again, so that it is possible to use repeatedly, and also durability due to washing or the like can be obtained.

Japanese Utility Model Application S59-26076 (Japanese Utility Model Publication S60-140789) microfilm Japanese Utility Model Application S61-8590 (Japanese Utility Model Publication S62-122879) Microfilm Japanese Patent Laid-Open No. S63-243379 Japanese Patent Application Laid-Open No. H04-11006 Japanese Patent Application Laid-Open No. H06-49712

However, the above-described methods of Patent Documents 1 and 2 have disadvantages such as a high cost of a hybrid process and a difference in dyeability of each fiber.

In the method of Patent Document 3, since the smoothing agent is removed due to changes in textures due to post-processing, washing, or the like, durability is deteriorated.

Further, in the methods of Patent Documents 4 and 5, when a polyolefin is used as the low melting point polymer of the core portion, since the affinity with the polyester is insufficient, core-sis peeling easily occurs in spinning, , Resulting in deterioration of processability and color unevenness. Particularly, in the case of performing a twist processing with a large heat and an external force at a processing temperature equivalent to that of the polyester fiber, not only the peeling of the core portion and the sheath portion but also cracks in the sheath portion and leakage of the polyolefin in the core portion, There arises a problem that a large amount of 100% occurs. On the contrary, when the polyester composite fiber is subjected to conditions under which the processing temperature condition is relaxed, the polyester conjugate fiber is not thermally set, and sufficient stretchability and bulky property are not obtained.

Accordingly, an object of the present invention is to provide a polyester conjugate fiber for friction-fusible foaming, which is improved in workability and durability, and to provide a false-twist construction and a fabric using the same.

As a result of intensive studies, the inventors of the present invention have found that by using a polymer alloy technique and forming a sea-island alloy structure in which polyolefin is stably dispersed in a polyester, it is possible to reduce peeling of the polymer interface due to heat and external force Polyester-conjugated fiber having a friction-melting property was obtained. Further, it has been found that, in addition to the above, by forming the polymer alloy in the core portion and the polyester in the sheath portion in the form of a fiber cross-section, an improvement in defects due to some exposures is obtained. It has also been found that a polyester composite fiber having good dyeability is obtained by taking a sea-island alloy structure in which a core-added polyester has a polyolefin dispersed therein and completely covering the core portion with the sheath portion.

That is, the present invention is a conjugate fiber comprising a core part and a sheath part which completely covers the core part, wherein the polymer of the core part is a polymer alloy comprising two or more kinds of thermoplastic polymers and the polymer alloy is composed of a polyester, a polyolefin and a compatibilizing agent, Wherein the polymer alloy is formed by forming a sea-island alloy structure of a sea phase polyester and an island phase polyolefin, and the polymer of the sheath portion is a polyester. .

Among them, it is preferable that the polyolefin is at least one kind of polymer selected from the group consisting of low density polyethylene, linear low density polyethylene and high density polyethylene. The mass ratio of the polyester and the polyolefin in the polymer alloy of the core portion is preferably 95: 5 to 55: 45.

Further, the present invention is also a flammable construction comprising the above-mentioned composite fibers. The twisted yarn of the present invention preferably has a stretch shrinkage ratio of 20% or more, more preferably a residual torque of 30 T / m or more, still more preferably 3.0 cN / dtex or more and an elongation of 20% or more.

In the present invention, the polymer of the core portion is a polymer alloy comprising two or more kinds of thermoplastic polymers, and the polymer alloy is composed of a polyester, a polyolefin and a compatibilizing agent, and the polymer alloy is a polyester in which the sea phase is polyester, And is formed by using a composite fiber in which the core portion is not exposed to the surface of the fiber and is subjected to a twisting process at a heater temperature of 180 to 220 DEG C and a twist number of 2000 to 4000 T / m.

The present invention is also an anti-friction, meltblown fabric using at least a part of the composite fiber or the combustible construction.

According to the present invention, it is possible to provide a friction-fusible composite fabric for warp-on with excellent processability and dyeability.

Further, by using the friction-melting polyester fiber composite material of the present invention, it is possible to provide a false-twist yarn or a fabric with good resistance to friction, melt processability, and dyeability.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view showing an example of a fiber cross section of a composite fiber of the present invention. FIG.

Hereinafter, the present invention will be described in detail.

The present invention is a composite fiber comprising a polymer of a core portion and a polymer of a sheath portion.

The polymer in the core portion is a polymer alloy comprising two or more kinds of thermoplastic polymers, and the polymer alloy is formed of a sea-island polyester and an island-like polyolefin sea-structure.

First, the polymer of the sheath portion in the present invention and the polyester which is a sea phase of the core portion will be described.

The polyester of the present invention is a polymer synthesized from dicarboxylic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof. Examples of such polyesters include polyethylene terephthalate, polybutylene terephthalate, and polypropylene terephthalate. Polyethylene terephthalate or polybutylene terephthalate is preferred from the viewpoint of mechanical properties and radiating properties.

These polyesters may be copolymerized with other components as long as the object of the present invention is not impaired. Specific examples of the dicarboxylic acid component as the copolymerization component include isophthalic acid, naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, adipic acid, sebacic acid and ester-forming derivatives thereof. Examples of the diol component include diethylene glycol, hexamethylene glycol, neopentyl glycol, and cyclohexanedimethanol. Polyoxyalkylene glycols such as polyethylene glycol and polypropylene glycol may also be used. The copolymerization amount is preferably 10 mol% or less, more preferably 5 mol% or less, per repeating unit constituted.

As the method for producing the polyester in the present invention, firstly, esterification or ester exchange reaction is carried out by using the above-mentioned dicarboxylic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof as main starting materials according to a conventional method Followed by carrying out a polycondensation reaction under further high temperature and reduced pressure.

The viscosity of the polyester in the present invention is not particularly limited, but a polyester having an intrinsic viscosity [?] Which is used in ordinary polyester fibers can be used. The polyethylene terephthalate is preferably polyethylene terephthalate having an intrinsic viscosity [?] Of 0.4 to 1.5, more preferably 0.55 to 1.0, in view of radioactivity and mechanical strength of the fiber.

In addition, within the scope of not impairing the object of the present invention, these polyesters contain small amounts of other polymers, antioxidants, heat stabilizers, quenchers, pigments, ultraviolet absorbers, fluorescent brighteners, plasticizers or other additives .

Next, the polyolefin which is an island phase of the core portion in the present invention will be described.

The polymer of the core portion is obtained by dispersing a polymer having a melting point lower than that of the polyester in the polyester to obtain an anti-friction melting property. In order to exhibit maximum frictional meltability, a polymer having a large difference in melting point from the polyester and having a large heat of fusion is preferable, and a polymer capable of withstanding the melt spinning temperature of the polyester is preferable. As a polymer satisfying these requirements, a polyolefin may be mentioned. The polyolefin includes, for example, low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene, polymethylpentene, and copolymers thereof. Of these, low-density polyethylene, linear low-density polyethylene, or high-density polyethylene is preferable as compared with polyolefins having different affinities with polyester and high heat of fusion. Particularly preferably, it is high-density polyethylene. The density of the low-density polyethylene is 0.910 to 0.929, the density of the linear low-density polyethylene is 0.930 to 0.941, and the density of the high-density polyethylene is 0.942 or more. These polyolefins may be used alone or in combination of two or more. The density referred to here is the ratio of mass and volume of a sample, expressed in g / cm 3.

To the extent that the object of the present invention is not impaired, these polyolefins may contain small amounts of other polymers, antioxidants, heat stabilizers, quenchers, pigments, ultraviolet absorbers, fluorescent brighteners, plasticizers or other additives Can be.

The mass ratio of the polyester to the polyolefin in the polymer alloy of the core portion in the present invention is preferably 95: 5 to 55: 45, more preferably 85: 15 to 60:40, and even more preferably 80:20 ~ 65: 35. When the amount of the polyolefin is less than 5% by mass, there is a possibility that sufficient friction resistance can not be obtained as the obtained polyester conjugate fiber. On the other hand, when the amount of the polyolefin is more than 45% by mass, the dispersibility of the polyolefin into the polyester is deteriorated, and the radioactivity deteriorates, and the sea phase and the island phase of the phase structure may be reversed.

Next, the compatibilizing agent contained in the polymer alloy of the core part in the present invention will be described.

Since the compatibility of the polyester with the polyolefin is insufficient, the polymer alloy of the core part in the present invention is poor in the dispersibility of the polyolefin in the polyester obtained by melt mixing by the ordinary method, The lowering of the physical properties of the substrate is caused. Therefore, in the present invention, it is necessary to add a compatibilizing agent to the polymer alloy. The compatibilizing agent in the present invention is a compound that stabilizes the molar ratio of both polymers by acting on the polymer interface when two or more kinds of polymers are mixed. In the present invention, the addition of a compatibilizer serves to stabilize the dispersion of the polyolefin in the polyester and to improve the radioactivity. This makes it possible to stably disperse the polyolefin in the polyester. In the case of the polymer alloy of a polyester and a polyolefin in the present invention, a modified polyolefin may be mentioned as a compatibilizing agent to be used. The modified polyolefin is a polyolefin having functional groups such as a carboxylic acid, a carboxylic acid metal base, a carboxylic acid ester group, an acetic anhydride and an epoxy group in the molecule. If the monomers having these functional groups are copolymerized polyolefins, they may be any of random copolymers, block copolymers and graft copolymers. Examples of the polyolefin include polymers containing polyethylene, polypropylene, and polybutene as main components, copolymers such as ethylene / propylene copolymer, ethylene / butene copolymer, and ethylene / hexene copolymer.

Specific examples of the compatibilizing agent usable in the present invention include ethylene / acrylic acid copolymer, ethylene / methacrylic acid copolymer, ethylene / ethyl acrylate copolymer, ethylene / vinyl acetate copolymer, ethylene / methacrylic acid glycidyl copolymer, ethylene / Vinyl acetate / glycidyl methacrylate copolymer, maleic anhydride grafted polyethylene, acrylic acid grafted polyethylene, maleic anhydride grafted ethylene / propylene copolymer, ethylene / propylene-methacrylic acid grafted glycidyl copolymer, maleic anhydride Graft ethylene / propylene / 1,4-hexadiene copolymer, and acrylic acid graft ethylene / vinyl acetate copolymer. These compatibilizers may be used alone or in combination of two or more.

The amount of the compatibilizing agent to be added is preferably from 0.1 to 30 mass% (external addition), more preferably from 0.3 to 20 mass%, based on the entire polymer alloy. When the amount of the compatibilizing agent is less than 0.1 mass%, it is difficult to improve compatibility between the polyester and the polyolefin. On the other hand, when the amount of the compatibilizing agent is more than 30 mass%, the emulsion itself becomes undissolved and deteriorates radioactivity and fiber properties. Can not do it.

The method for producing the polymer alloy in the present invention is not particularly limited, and examples thereof include (1) a method in which polyester, polyolefin and compatibilizing agent are dry blended and then directly fed into a radiator and mixed in a radiator flow path; ) A method of dry blending a polyester, a polyolefin and a compatibilizing agent, followed by melting and kneading using various general kneaders, and (3) a method of introducing a polyolefin and a compatibilizing agent into a polyester into an extruder.

Examples of the kneader include a single screw extruder, a twin screw extruder, a roll mixer, and a Banbury mixer. Among them, a biaxial kneading extruder is preferable in terms of workability and kneading property.

Next, the composite fiber of the present invention will be described.

The composite fiber of the present invention can be obtained by preparing a polymer alloy comprising the polyester, the polyolefin and the compatibilizing agent as the polymer of the core part, and the polyester as the polymer of the sheath part, drying them by a usual method, . ≪ / RTI > The term " conjugate fiber " as used herein refers to a composite (conjugate) fiber obtained by melting a polymer alloy and a polyester, respectively, and bonding them in various shapes upon spinning.

The spinning method is not particularly limited. For example, there may be used a so-called Convein method (CONVE method), a direct spinning method (spin draw method) in which an unstretched yarn is wound at a low speed, And the POY method for obtaining a partially undecided gentleman. Further, it is preferable to employ the spin draw method and the POY method in terms of labor-saving and inexpensive production.

The composite fiber of the present invention has a fiber cross-sectional shape in which a core portion is provided with a polymer alloy component and a polyester component is disposed on a sheath portion which completely covers the core portion. Covering the core part completely means that the core part is not exposed on the fiber surface. When the polymer alloy component is exposed to the surface, the polyolefin, which is a part of the islands, is exposed, resulting in deterioration of radioactivity. Therefore, by taking the shape in which the polymer alloy component is completely covered with the polyester component, the polyester conjugated fiber can be produced without the drawbacks thereof.

As described above, the fiber cross-sectional shape of the composite fiber of the present invention is not particularly limited as long as it is a fiber cross-sectional shape in which a polyester component is disposed in a sheath portion completely covering the polymer alloy component and core portion in the core portion. A core-sheath type of a single core as shown in Fig. 1 (A), and a core-sheath type of multi-core as shown in Fig. 1 (B).

The core portion and the sheath portion preferably have a volume ratio (core portion: sheath portion) of 95: 5 to 20: 80, more preferably 80: 20 to 30: Lt; / RTI > When the core portion is smaller than 20% by volume, the polyester of the sheath portion becomes thick, which makes it difficult to obtain the frictional meltability. When the sheath portion is smaller than 5% by volume, the fiber strength is lowered, which is undesirable.

The composite filament thus obtained preferably has a fineness / filament count of 22 to 267 dtex / 12 to 72f, more preferably 50 to 168 dtex / 12 to 48f, in view of the case where the composite filament is used in a product requiring friction- Is more preferable.

The composite fiber of the present invention preferably has a strength of at least 3.0 cN / dtex in view of the mechanical properties practicable as a product. More preferably at least 3.5 cN / dtex. The elongation is preferably 20% or more, more preferably 25% or more, and further preferably 30% or more.

The false-twist yarn of the present invention can be obtained by twisting the composite fiber.

The flammable processing method can be either a pin method or a friction method, but a friction method with good production efficiency is preferable.

In the present invention, at the time of the tentative processing, the heater temperature is preferably 180 to 220 DEG C and the twist number is preferably 2000 to 4000 T / m.

Hereinafter, a description will be given in detail of a typical manufacturing method of the tentative processing.

For example, when the drawn yarn is subjected to the fusing process in a pin-like manner, it is preferable that the yarn is in the range of 50 to 200 m / min, the twist number is in the range of 2,000 to 4,000 T / m and the heater temperature is in the range of 180 to 220 ° C.

When the POY yarn is subjected to twist processing in a frictional manner, the yarn is preferably 700 to 900 m / min, the twist number is preferably 2000 to 4000 T / m, the drawing magnification is 1.5 to 2 times, 220 < 0 > C.

Also, in order to make the noble property and stretching and shrinkage restoration ratio favorable, a two-heater type is preferable.

Further, since the composite fiber of the present invention can be processed at a customary heater temperature (for example, 180 to 220 캜) used in ordinary polyester single yarn, it is easy to obtain a superior sagging property and excellent handling property . When the heater temperature is too low, the crimp is not sufficiently given. On the contrary, when the heater temperature is excessively high, fusion between the filaments tends to occur, and tight spots (streaks, margins) tend to occur easily.

In addition, the following twist coefficient is preferably 26500 to 34900.

Referring to the above formula, the range of the number of twists is in the range of 3000 to 4000 T / m when the fineness is about 84 dtex and in the range of 2000 to 3000 T / m when the fineness is about 167 dtex. In general, the twist number is preferably about 2000 to 4000 T / m.

If the number of twists is excessively small, the crimp tends to be defective. In the case where the twist is too large, double twisting or the like tends to occur. Therefore, the number of twists is preferably set within a range of twist counts calculated from the twist coefficient Do.

The thus obtained false twist yarn of the present invention is excellent in stretchability and excellent in sag.

Considering the case where the false-twist yarn of the present invention is used in a product requiring friction-fusing resistance, the fineness / filament count is preferably 22 to 267 dtex / 12 to 72f, more preferably 50 to 168 dtex / 12 to 48f Do.

The stretch shrinkage ratio of the present invention is preferably not less than 20%, more preferably not less than 25%, from the standpoint of satisfactorily maintaining the processability, processability and friction resistance of the dyeing process.

The residual torque of the false-twist yarn of the present invention is preferably not less than 30 T / m, more preferably not less than 50 T / m, from the standpoint of satisfactorily maintaining the processability, processability and friction resistance of the dyeing process.

The strength of the false-twist yarn of the present invention is preferably 3.0 cN / dtex or more in terms of satisfactorily maintaining the straight-line process, the processability of the dyeing process, the feasible mechanical properties and the frictional meltability as a product, and the elongation is 20% , More preferably at least 25%, and even more preferably at least 30%.

Such a false twist yarn of the present invention is excellent in stretchability and excellent in nobility.

The composite fiber and the false-twist yarn of the present invention can be used suitably for the anti-friction, meltblown fabric.

When the friction-fusible fabric is produced by using the composite fiber or the burnable construction of the present invention, the type of the fabric is not particularly limited, and may be any of woven fabric, knitted fabric, and nonwoven fabric.

The anti-friction, meltblown fabric of the present invention includes at least a part of the composite fiber or the combustible construction of the present invention.

The friction-fusible foil of the present invention is preferably used for the surface to be frictioned, and may be used only for the surface to be frictioned or for the entire fabric.

The friction-fusible composite fabric for reinforcing fibers according to the present invention was subjected to 10 seconds of contact pressure friction with a load of 2 kg in a rotor-type friction-melting test conforming to JIS L1056 (Method B) It is preferable to use it for the friction and meltblown fabric, more preferably for the friction-resistant meltblowing that can not see the melting marks when the 13-second contact friction is performed, more preferably 15 seconds for the contact friction It is to be used in an inner friction meltbag which can not see a trace of melting.

(Industrial availability)

The composite fiber, the false twisting work and the fabric of the present invention can be suitably used as a material for sports medicine such as school sports, medical care, volleyball, basketball, handball, and the like.

Example

Hereinafter, the present invention will be described in detail by way of examples. The present invention is not limited to the embodiments described below. The evaluation items in the examples and the comparative examples were measured by the following methods.

(1) Intrinsic viscosity [η]

Was measured in a mixed solvent of phenol / tetrachloroethane = 6/4 (weight ratio) at 20 占 폚 by a conventional method.

(2) MFR (g / 10 min)

The measurement method was in accordance with JIS K 6922-2.

(3) Spinning performance

When the yarn was radiated for 24 hours, it was found that there was no yarn breakage once, and when the yarn break occurred, the yarn was judged as X.

(4) Mechanical properties of the fiber (strength and elongation)

A tensile test was carried out using Autograph AGS manufactured by Shimadzu Corporation. The breaking strength and elongation at break of the fiber were measured five times under the conditions of a measuring length of 200 mm and a tensile speed of 200 mm / min, and the average value thereof was calculated I was a robber, a shinto.

(5) Flammability

The operability when the false twisting process was carried out was evaluated according to the following criteria.

○: No thread breaks, no sagging

X: Thread break occurred, other error occurred

(6) Elastic restoration rate

Measured according to JIS L1013 8.12.

(7) Residual torque

The twist number of 25 cm in length under a load of 0.2 g / dex was measured with a twist tester and the obtained twist number (T / 25 cm) was multiplied by 4 to calculate the residual torque (T / m).

(8) Dyeability

The obtained yarn was used as a circular kneaded product. After refining, the dyed yarn was dyed in a bath of D / N BLUEACE 1.0% owf, acetic acid 0.2 ml / L and ionone RP 1.0 g / L in a bath ratio of 1:20 at 130 ° C and 60 Minute, stained and observed with naked eyes. The results were evaluated as? (Good dyeability) and X (poor dyeability).

(9) Friction melting property

The obtained yarn was used as a circular kneading, and a rotor-type friction-melting test was used in accordance with JIS L1056 (Method B). The state of the fabric surface after pressing for 10 seconds under a load of 2 kg was evaluated in the following three steps:? (With no marks of melting and scratches and marks),? (With some marks of melting) Respectively.

[ Example  One]

A polyethylene terephthalate resin having an intrinsic viscosity of 0.64, high density polyethylene having a MFR of 7.0 and a density of 0.964 (Japan Polyethylene Corporation) and an ethylene-glycidyl methacrylate copolymer (Sumitomo Chemicals Co., Ltd.) as a compatibilizer. , BONDFAST, Grade: 2C) were blended in a predetermined amount as shown in Table 1, blended and dry blended, and fed to a biaxial kneading extruder. The mixture was melt-kneaded under the conditions of a kneading temperature of 270 DEG C and a screw rotation speed of 250 rpm, Pelletized to obtain a polymer alloy to be used for the core part. On the other hand, polyethylene terephthalate having an intrinsic viscosity [?] Of 0.64 was used as the sheath portion. Each of the polymers was dried and then introduced into a complex radiator to melt the polymer alloy and the polyethylene terephthalate at a volume ratio of 2: 1 to obtain a polymer alloy in the core portion of Fig. 1 (A) and polyethylene terephthalate in the sheath portion (Temperature: 80 占 폚) of the first high detent roller GR1 after the emulsion is applied in the usual manner and subsequently the extruded material is discharged from the radial cloud at a peripheral speed of 4300 m / Min (temperature: 130 占 폚), and a core-sheath type conjugate fiber of 167 dtex / 48f was obtained by a normal spin draw method in which GR1 and GR2 were stretched. The resulting composite fiber was subjected to a twist processing under the conditions of a heater temperature of 200 占 폚, a speed of 100 m / min, and a twist number of 2800 T / m to obtain a twin-burnable construction exhibiting excellent false-twist processability without defect. The obtained false-twist yarn had a strength of 3.14 cN / dtex, an elongation of 20.5%, a shrinkage recovery ratio of 31%, and a residual torque of 106 T / m. Using the obtained smokestack construction, a circular piece was produced, and the friction resistance and the dyeability were evaluated. The results are shown in Table 1.

[ Example  2]

Except that the mass ratio of the polyethylene terephthalate and the high-density polyethylene in the polymer alloy was changed to 65:35 as shown in Table 1, the addition amount of the compatibilizing agent was changed from 0.3 mass% to 0.5 mass%, and the number of filaments was changed. 167 dtex / 72f core-sheath type conjugate fiber was obtained in the same manner as in Example 1. Further, a false twisting process was carried out under the same conditions as in Example 1, and a false twisting work with excellent nobleness was obtained without a defect. The friction resistance and the durability were evaluated by using the obtained smokestack construction. The results are shown in Table 1.

[ Example  3]

Core-sheath type conjugate fiber of 167 dtex / 72f was obtained in the same manner as in Example 1, except that the polymer alloy polyolefin was changed to a linear low density polyethylene having an MFR of 5.0 and a density of 0.935, and the number of filaments was changed. The same conditions as those of the examples were subjected to twist processing, and a false twisting work with a high degree of sophistication without defects was obtained. Evaluation of tribological melting resistance and durability were carried out by using the obtained twist construction.

[ Comparative Example  One]

Polyethylene terephthalate having an intrinsic viscosity [?] Of 0.64 was used, and polyethylene terephthalate fibers at 167 dtex / 72 f were obtained. Further, when the false twisting process was carried out under the same conditions as in Example 1, false twisting work with excellent nobleness was obtained without fault. The obtained twisted yarn had a strength of 4.01 cN / dtex, an elongation of 24.5%, a stretch shrinkage ratio of 37.2%, and a residual torque of 138 T / m. The friction resistance and the durability were evaluated by using the obtained smokestack construction. The results are shown in Table 1.

[ Comparative Example  2]

Density polyethylene having an MFR of 2.3 as the core portion polymer and polyethylene terephthalate having an intrinsic viscosity [?] Of 0.64 as the sheath portion polymer at a volume ratio of 1: 3 and having a density of 167 dtex / 72f Of the core-sheath type conjugate fiber. When a twist was applied under the same conditions as in Example 1, cracks were generated in the sheath portion, exposure of the high density polyethylene in the core portion was confirmed, a large amount of white powder was produced, and a lot of yarn breakage occurred. It was found that only a small amount was obtained because of the poor flame-retardant processability. However, evaluation of the friction resistance and durability were conducted by using it. The results are shown in Table 1. The obtained twisted yarn had a strength of 2.60 cN / dtex, elongation of 20.4%, elongation and shrinkage recovery of 32.6%, and residual torque of 130 T / m.

[ Comparative Example  3]

Only the polymer alloy of the core portion used in Example 1 was used, and single irradiation was performed at 167 dtex / 72f. However, high-density polyethylene exposed on some surfaces caused white spots, resulting in frequent yarn breakage. In addition, whitening occurred in the false twisting process, and thread breakage frequently occurred.

All of the conjugate fibers obtained in Examples 1 to 3 were excellent in radioactive and flammability, and excellent in friction resistance and durability. On the other hand, the polyethylene terephthalate sole fiber of Comparative Example 1 was inferior in resistance to friction and abrasion, and the core-sheath type composite fiber obtained in Comparative Example 2 in which the core portion was polyethylene and the sheath portion was polyethylene terephthalate had poor tinning property and dyeability . In addition, the individual fibers of the polymer alloy obtained in Comparative Example 3 were poor in radioactive and flammability.

[ Example  4]

Polyethylene terephthalate having an intrinsic viscosity [eta] of 0.64, high-density polyethylene having an MFR of 7.0 and a density of 0.964 (Japan Polyethylene Corporation), and an ethylene-glycidyl methacrylate copolymer (Sumitomo Chemicals Co., Ltd. BONDFAST, grade: 2C) were blended in a predetermined amount as shown in Table 2, respectively, and dry blended. The blend was fed to a twin-screw kneading extruder and melted and kneaded under conditions of a kneading temperature of 270 DEG C and a screw rotation speed of 250 rpm, And cooled to obtain a polymer alloy used for the core portion. On the other hand, polyethylene terephthalate having an intrinsic viscosity [?] Of 0.64 was used as the sheath portion. Each polymer was dried and then introduced into a composite radiator to melt the polymer alloy and polyethylene terephthalate at a volumetric ratio of 2: 1 to form a polymer alloy in the core portion of Fig. 1 (A) and a polymer alloy in the cistern portion to spin to become polyethylene terephthalate The core-sheath type conjugated fiber (POY yarn) of 150 dtex / 24f was obtained by the POY method at a spinning speed of 4300 m / min after the emulsion was applied in a usual manner. The resultant core-sheath type composite fiber was subjected to a twisting process at a yarn speed of 760 m / min while being stretched to 1.785 times by a friction method under conditions of a heater temperature of 200 캜, a subordinate speed of 760 m / min, and a twisting number of 3100 T / m Bar, flexible construction with excellent stretchability and high nobility. The obtained twisted yarn had a fineness of 84 dtex / 24f, a stretch shrinkage percentage of 26%, a residual torque of 51 T / m in the Z direction, a strength of 3.3 cN / dtex and an elongation of 31%. In addition, the friction-melting property and the dyeability were evaluated using the false-twist construction. The results are shown in Table 2.

[ Example  5]

In the same manner as in Example 4, an undrawn yarn of core-sheath type conjugate fiber was wound up at a spinning speed of 1,600 m / min. The obtained undrawn yarn was stretched to 3.120 times to obtain 84 dtex / 24f core-sheath type conjugated fiber (drawn yarn). The obtained core-sheath type conjugated fiber was twisted in a pinning manner at a twisting speed of 120 m / min, a heater temperature of 200 캜, and a twist number of 3100 T / m. The resulting false twist yarn had good stretchability and sophistication. The twisted yarn had a fineness of 84 dtex / 24 f, a stretch shrinkage percentage of 26%, a residual torque of 53 T / m in the Z direction, a strength of 3.2 cN / dtex and an elongation of 32%. In addition, the friction-melting property and the dyeability were evaluated using the false-twist construction. The results are shown in Table 2.

[ Comparative Example  4]

Polyethylene terephthalate having an intrinsic viscosity [?] Of 0.64 was used, and single fibers at 84 dtex / 24f were obtained. The obtained fiber was subjected to flammability processing in the same manner as in Example 4. Table 2 shows the physical properties and evaluation of the obtained smokestack construction.

[ Comparative Example  5]

A polyethylene terephthalate having an intrinsic viscosity [?] Of 0.64 and a volume ratio of 1: 3 were used as the polymer of the core portion and high-density polyethylene having an MFR of 2.3 and a sheath portion polymer of 84 dtex / 24f To obtain a core-sheath type conjugated fiber. When the obtained core-sheath type conjugate fiber was subjected to a twist processing in the same manner as in Example 4, cracks were generated in the sheath portion, exposure of high density polyethylene as a core component was confirmed, a large amount of white powder was generated, However, a small amount of false twisting yarn was obtained. Table 2 shows the physical properties and evaluation results of the obtained smokestack construction.

[ Comparative Example  6]

Spun as a sole component of the polymer alloy of the core part obtained in Example 4 to obtain fibers of 84 dtex / 24f. At the time of spinning, high-density polyethylene was exposed on some surfaces, whitening occurred, and yarn breakage was frequent. When the obtained fibers were subjected to a false-twisting process in the same manner as in Example 4, whitening occurred and the yarn breakage was frequent, but a very small amount of false twisting was obtained. Table 2 shows the evaluation results of the obtained smokestack construction.

In the false-twist yarns obtained in Examples 4 and 5, core-sheath peeling did not occur in both the spinning process, the twisting process, and the post-process such as dyeing. These false twisting yarns are excellent in stretchability and sophistication, and are also excellent in friction resistance and melting, and can be dyed without staining unevenness in the dyeing step, durability is excellent, and stretchability and nobility are excellent.

The false-twist yarn using the polyethylene terephthalate sole fiber obtained in Comparative Example 4 was inferior in friction resistance to melting, and the core portion obtained in Comparative Example 5 was made of polyethylene and the sheath portion was made of polyethylene terephthalate, The processed yarn had core-sheath peeling, poor dyeability, and poor friction resistance in comparison with the products of Examples. Further, in the fibers made of the polymer alloy obtained in Comparative Example 6, whitening occurred in all of the spinning process and the twisting process, and yarn breakage occurred frequently, uneven dyeing occurred during dyeing, and the friction resistance was poor.

[ Example  6]

Polyethylene terephthalate having an intrinsic viscosity [eta] of 0.64, high-density polyethylene having an MFR of 7.0 and a density of 0.964 (Japan Polyethylene Corporation), and an ethylene-glycidyl methacrylate copolymer (Sumitomo Chemicals Co., Ltd., BONDFAST, grade: 2C) were blended and dry-blended in the same manner as in Example 4, and then fed to a twin-screw kneading extruder and melt-kneaded under the conditions of a kneading temperature of 270 ° C and a screw rotation speed of 250 rpm , And cooled to obtain a polymer alloy used for the core part. On the other hand, polyethylene terephthalate having an intrinsic viscosity [?] Of 0.64 was used as the sheath portion. Each of the polymers was dried and then introduced into a complex radiator to melt the polymer alloy and the polyethylene terephthalate at a volume ratio of 2: 1 to obtain a polymer alloy in the core portion of Fig. 1 (A) and polyethylene terephthalate in the sheath portion Extruded from a spinneret, and an untreated filament was obtained at a spinning speed of 1,600 m / min after the application of an emulsion by a usual method and stretched at 84 占 폚 at 3.12 times to obtain a core-sheath type conjugated fiber of 84 dtex / 24f ). The resulting core-sheath type composite fiber was subjected to a twisting process in a fin manner under conditions of a heater temperature of 200 占 폚, a speed of 120 m / minute, and a twist number of 3100 T / m, whereby a false twisting work excellent in stretchability and nobility was obtained. The obtained twisted yarn had a fineness of 84 dtex / 24 f, a stretch shrinkage percentage of 26%, a residual torque of 51 T / m in the Z direction, a strength of 3.3 cN / dtex and an elongation of 30%. Regular polyester yarns of 84 dtex / 72 f and 84 dtex / 36 f were arranged on the yarn obtained on the surface with a 22 gauge circular knitting machine and regular yarns of regular yarns of 84 dtex / 72 f and regular yarns of 84 dtex / To obtain a knitted fabric having a unit area weight of 250 g / m < 2 >. The friction stir welding test was carried out by using the knitted fabric obtained and using a rotor-type friction-melting test according to JIS L1056 (Method B). The surface of the fabric after pressing for 10 seconds under a load of 2 kg had scratches and marks but no signs of melting.

[ Example  7]

A knitted fabric having a unit area weight of 250 g / m 2 was produced in the same manner as in Example 6, except that the core-sheath type conjugated fiber (drawn yarn) of 84 dtex / 24 f obtained in Example 6 was not subjected to the twist processing The friction test was carried out. The surface of the fabric after pressing for 10 seconds under a load of 2 kg was scratched and there was no trace of melting.

[ Comparative Example  7]

A knitted fabric having a unit area weight of 250 g / m 2 was produced in the same manner as in Example 6, except that the obtained false twisting work was changed to a polyethylene terephthalate 84 dtex / 24 f polyethylene terephthalate fiber having an intrinsic viscosity of 0.64, Friction resistance test was carried out in the same manner as in Test No. 6. When pressed with a load of 2 kg, in 3.0 seconds or less, the fabric was punctured and broken.

[ Comparative Example  8]

A core of 84 dtex / 24f was produced in the same manner as in Example 6, except that polyethylene terephthalate having an intrinsic viscosity [eta] of 0.64 was used as the core portion and high density polyethylene having an MFR of 2.3, and the volume ratio was 1: - sheath type composite fibers were obtained and subjected to a false twisting process to produce a knitted fabric. However, a processed yarn amount capable of producing a knitted fabric by the occurrence of white streaks due to core-sheath separation was not obtained.

[ Comparative Example  9]

Using a core-sheath type composite fiber obtained in Comparative Example 8, a knitted fabric (unit area weight of 250 g / m 2) was produced in the same manner as in Example 6, and subjected to an inner friction melting test. The surface was not torn, but there was evidence of melting.

The result of the friction resistance test of Examples 6 and 7 and Comparative Examples 7, 8 and 9 (the state of the cloth after the cloth was pressed down for 10 seconds under a load of 2 kg), and in this test, when the cloth was pressed with a load of 2 kg, The time until fracture of the hole (time until breakage) is shown in the following Table 3 together with the evaluation results of spinning workability, smellability and durability.

The results of the friction resistance test were evaluated according to the following criteria.

○: No melting marks, only scratches and marks

Δ: Partial melting mark

X: The sample is broken, and the hole is pierced.

The fibers obtained in Examples 6 and 7 were all excellent in spinnability and toughness, and excellent in friction resistance and durability. On the other hand, the polyethylene terephthalate sole fiber obtained in Comparative Example 7 had poor friction resistance. The core-sheath type conjugate fiber obtained in Comparative Example 8 in which the core portion was polyethylene and the sheath portion polyethylene terephthalate had low toughness and durability. The core-sheath type conjugated fiber of Comparative Example 9, in which the core portion was made of polyethylene and the sheath portion was made of polyethylene terephthalate, which was not subjected to the tentative working, was superior in dyeability, It was falling behind.

a: polymer alloy component
b: polyester component

Claims (9)

A composite fiber comprising a core portion and a sheath portion which completely covers the core portion,
Wherein the polymer of the core portion is a polymer alloy comprising two or more kinds of thermoplastic polymers and the polymer alloy is composed of a polyester, a polyolefin and a compatibilizing agent, wherein the polymer alloy is a polyester in an ocean phase and an island structure in a polyolefin in an island phase, And the negative polymer is a polyester. The friction-melting cloth-forging composite fiber according to claim 1, wherein the polyolefin is at least one kind of polymer selected from the group consisting of low-density polyethylene, linear low-density polyethylene and high-density polyethylene. The friction-fusible composite warp-knitting fabric according to claim 1 or 2, wherein the weight ratio of the polyester of the polymer in the core portion and the polyolefin is 95: 5 to 55: 45. A fire-retardant construction comprising the composite fiber according to any one of claims 1 to 3. The smokestack construction according to claim 4, wherein the stretch shrinkage ratio is 20% or more. The smokestack construction according to claim 4 or 5, wherein the residual torque is 30 T / m or more. The combustible construction according to any one of claims 4 to 6, wherein the strength is 3.0 cN / dtex or more and the elongation is 20% or more. The polymer alloy according to any one of claims 4 to 7, wherein the polymer of the core portion is a polymer alloy comprising two or more kinds of thermoplastic polymers, and the polymer alloy is composed of a polyester, a polyolefin and a compatibilizing agent, Ester and island phase polyolefin composite fibers which are not exposed on the surface of the core portion and which are subjected to flammable processing under the conditions of a heater temperature of 180 to 220 DEG C and a twist number of 2000 to 4000 T / Gt; An anti-friction, meltblown fabric using at least a part of the composite fiber according to any one of claims 1 to 3 or the false twist fabric according to any one of claims 4 to 7.

Images