JP2020165050A - Core-sheath type polymer alloy fiber, fiber aggregate containing the same, and manufacturing method of the same - Google Patents

Abstract

To provide a core-sheath type polymer alloy fiber which can be stably spun with almost no breakage of yarn and has good dyeability and color fastness, and to provide a manufacturing method of the fiber, and a fiber aggregate containing the fiber.SOLUTION: There is provided a core-sheath type polymer alloy fiber in which a first component as either one of the core component and the sheath component comprises a polymer alloy containing a polyolefin as a sea component and a polyester as an island component, the island component being discretely dispersed in the length direction of the fiber, and a second component as the other of the core component and the sheath component comprises a polyolefin. Further, the polymer alloy contains a styrene-based elastomer, and the styrene-based elastomer has a weight-average molecular weight (Mw) of 100,000 or more. In manufacturing the core-sheath type polymer alloy fiber, it is preferred that the spinning temperature of the first component containing the polymer alloy is between Tm or higher and Tm+15°C or lower, where the melting point of the polyester is defined as Tm.SELECTED DRAWING: Figure 1

Description

The present invention relates to a core-sheath type polymer alloy fiber in which either one of the core component and the sheath component contains a polymer alloy, a fiber assembly containing the same, and a method for producing the same. In detail, the present invention is stable with almost no thread breakage. The present invention relates to a core-sheath polymer alloy fiber that can be spun and has good dyeability and dyeing fastness, a fiber assembly containing the same, and a method for producing the same.

Polyolefin-based fibers composed of polyolefins such as polypropylene are widely used in clothing, industrial materials, and the like because they are excellent in light weight and heat retention. Further, polyester fibers made of polyester such as polyethylene terephthalate are widely used for clothing, industrial materials and the like because they are excellent in durability and dyeability. Therefore, in order to take advantage of these polymers, Patent Document 1 proposes a polymer alloy fiber using a polymer alloy of polyolefin and polyester.

International Publication No. 2018/079152

However, in polymer alloy fibers using polyolefin and polyester, in order to improve dyeability and dyeing durability, a core-sheath type polymer in which one of the core component and the sheath component is a polymer alloy of polyolefin and polyester is used. When an attempt was made to produce an alloy fiber, yarn breakage was likely to occur, and stable spinning could not be performed.

In order to solve the above problems, the present invention provides a core-sheath type polymer alloy fiber which can be spun stably with almost no yarn breakage and has good dyeability and dyeing fastness, a method for producing the same, and a fiber assembly containing the same. provide.

In the present invention, the first component of either the core component or the sheath component contains polyolefin as a sea component and polyester as an island component, and the island components are discontinuously dispersed in the length direction of the fiber. In a core-sheath type polymer alloy fiber containing polyolefin and the other second component of the core component and the sheath component contains polyolefin, the polymer alloy contains a styrene-based elastomer, and the styrene-based elastomer has a weight average molecular weight (Mw). The present invention relates to a core-sheath type polymer alloy fiber characterized by having a value of 100,000 or more.

The present invention also relates to a fiber structure containing the core-sheath polymer alloy fiber.

The present invention also comprises a first component containing a polyolefin as a sea component, a polyester as an island component, and a polymer alloy containing a styrene-based elastomer having a weight average molecular weight (Mw) of 100,000 or more as a compatibilizer. , When the step of melt-extruding the second component containing polyolefin using a core-sheath type nozzle to obtain a spun filament and the spinning temperature of the first component containing the polymer alloy is Tm as the melting point of the polyester. The present invention relates to a method for producing a core-sheath type polymer alloy fiber, which is characterized by having a temperature of Tm or more and Tm + 15 ° C. or lower.

According to the present invention, it is possible to provide a core-sheath type polymer alloy fiber which can be stably spun with almost no yarn breakage and has good dyeability and dyeing fastness, and a fiber assembly containing the same.
Further, according to the production method of the present invention, core-sheath type polymer alloy fibers having good dyeability and dyeing fastness can be stably spun with almost no yarn breakage.

FIG. 1 is a schematic view of a fiber cross section (cross section) of a core-sheath type polymer alloy fiber according to an embodiment of the present invention.

In the polymer alloy fiber using polyolefin and polyester, the present inventors use a polyolefin and polyester polymer alloy as the first component of either the core component or the sheath component in order to improve dyeability and dyeing durability. We diligently studied the inclusion of polyolefin in the other second component. As a result, by including a styrene-based elastomer having a weight average molecular weight (Mw) of 100,000 or more in the polymer alloy, the compatibility between the polyolefin and the polyester is improved, and at the interface between the polyolefin and the polyester in the first component, The fine dispersion of polyester in polyolefin improves the interfacial adhesiveness and spinnability of polyester and polyolefin. Furthermore, the compatibility between the polyolefins of the first component and the second component is also improved, and therefore the spinnability when melt-spun using the core-sheath type nozzle is improved, and the core has good dyeability and dyeing fastness. We have found that sheath-type polymer alloy fibers can be spun stably with almost no yarn breakage. Specifically, in the present invention, the first component of either the core component or the sheath component contains a polyolefin as a sea component and a polyester as an island component, and the island component is in the length direction (axial direction) of the fiber. In a core-sheath type polymer alloy fiber containing a discontinuously dispersed polymer alloy and containing a polyolefin as the other second component of the core component and the sheath component, the weight average molecular weight (Mw) of the polymer alloy is 100,000 or more. By including the styrene-based elastomer of the above, core-sheath type polymer alloy fibers having good dyeability and dyeing fastness can be stably spun with almost no thread breakage. In the present invention, "the island component is disperse discontinuously in the fiber length direction" means that the island component does not continuously exist in the fiber length direction and there is a portion where the island component does not exist. Means that. Therefore, the shape of the sea-island structure is not always the same in the cross section of the different fiber axes.

(1st component)
The first component has a sea-island structure containing polyolefin as a sea component and polyester as an island component, and further contains a polymer alloy containing a styrene-based elastomer as a compatibilizer.

In the polymer alloy, the styrene-based elastomer has a weight average molecular weight (Mw) of 100,000 or more. When the weight average molecular weight (Mw) of the styrene-based elastomer is 100,000 or more, the compatibility between polyester and polyolefin is improved, the interfacial adhesiveness between polyester and polyolefin is improved, and the core-sheath polymer alloy fiber is threaded. It can be spun stably without cutting. The weight average molecular weight (Mw) of the styrene-based elastomer is preferably 105,000 or more, more preferably 110,000 or more, and further preferably 115,000 or more. The weight average molecular weight (Mw) of the styrene-based elastomer is not particularly limited, but is preferably 200,000 or less, more preferably 175,000 or less, for example, from the viewpoint of spinnability, 150, Most preferably, it is 000 or less.

In the polymer alloy, when the weight average molecular weight (Mw) of the styrene-based elastomer is 100,000 or more, the styrene-based elastomer is a region or island composed of not only the interface between the polyolefin and the polyester but also only the polyolefin as a sea component. It tends to be present in the region consisting only of the polyester component, and therefore, in addition to the compatibility between the polyolefin and the polyester in the polymer alloy, the compatibility between the first component containing the polymer alloy and the second component containing the polyolefin is also compatible. It is presumed that the results will be improved and the core-sheath type polymer polyolefin fibers can be stably spun with almost no thread breakage. In particular, the weight average molecular weight (Mw) of polypropylene is 100,000 to 300,000, and since the styrene-based elastomer has the same weight average molecular weight (Mw), the compatibility tends to be better. When the weight average molecular weight (Mw) of the styrene-based elastomer is small, the styrene-based elastomer forms micelles, and the compatibility with polyester and polyolefin tends to decrease.

In the polymer alloy, the styrene-based elastomer preferably has a number average molecular weight (Mn) of 55,000 or more. More preferably, it is 60,000 or more. The upper limit of the number average molecular weight (Mn) of the styrene-based elastomer is not particularly limited, but is preferably 110,000 or less, and more preferably 100,000 or less. When the number average molecular weight (Mn) of the styrene-based elastomer is within the above range, the polyester is stably and finely dispersed in the polyolefin, the interfacial adhesiveness between the polyester and the polyolefin is improved, and the core-sheath type polymer alloy fiber is threaded. Stable spinning is possible with almost no breakage.

In the polymer alloy, the styrene-based elastomer preferably has a z average molecular weight (Mz) of 120,000 or more. When the z average molecular weight (Mz) of the styrene-based elastomer is 120,000 or more, the molecular chain becomes long and easily entangled with polyester or polyolefin, so that the compatibility between polyester and polyolefin is improved. The z average molecular weight (Mz) of the styrene-based elastomer is preferably 130,000 or more, more preferably 140,000 or more, and even more preferably 150,000 or more. The upper limit of the z average molecular weight (Mz) of the styrene-based elastomer is not particularly limited, but for example, from the viewpoint of reducing the dispersibility in polyester and polyolefin due to the molecular chain of the styrene-based elastomer becoming too long, 400,000. It is preferably less than or equal to, more preferably 350,000 or less, and most preferably 300,000 or less.

The styrene-based elastomer preferably contains less than 15% by mass of styrene blocks, more preferably 14% by mass or less, and further preferably 13% by mass or less, from the viewpoint of further enhancing the affinity with polyolefin. The styrene-based elastomer is not particularly limited, but for example, from the viewpoint that stable production of the styrene-based elastomer is difficult, it is preferable to contain 5% by mass or more of the styrene block, and more preferably 6% by mass or more. It is more preferable to contain 7% by mass or more. When the styrene content is less than 15% by mass (there are few styrene molecules), the content of ethylene / butylene, which is a block copolymerized soft segment, is large (there are many ethylene / butylene molecules), so that the ethylene / butylene is long. The molecular chain has a structure that is easily entangled with polyolefin and polyester, especially polyolefin, and has high compatibility, and stable spinning can be performed with almost no thread breakage.

Specifically, the styrene-based elastomer includes a styrene / butadiene block copolymer, a styrene / isoprene block copolymer, a styrene / butadiene / styrene block copolymer (SBS), and a styrene / isoprene / styrene block copolymer weight. Coalescence (SIS) and these hydrogenating agents styrene-butadiene-butylene-styrene block copolymer (SBBS), styrene-ethylene-butylene-styrene block copolymer (SEBS), and styrene-ethylene-propylene -Styrene block copolymer and the like can be mentioned. One of these may be used alone, or two or more thereof may be used in combination. Among them, the styrene-based elastomer is a styrene / ethylene / butylene / styrene block copolymer (SEBS) from the viewpoint of further improving the affinity between the styrene-based elastomer and the polyolefin and the polyester and the interfacial adhesiveness between the polyester and the polyolefin. It is preferable to have.

The styrene-based elastomer is preferably modified with a functional group such as an acidic group (acid anhydrous group), a carboxyl group, a hydroxyl group, an amino group, or an imino group. Examples of the acidic group include chain unsaturated carboxylic acids, examples of monovalent acids include oleic acid, linoleic acid and linolenic acid, and examples of divalent acids include maleic acid and fumaric acid. Among them, an acid anhydride (acid anhydride group) -modified styrene-based elastomer is preferable, and a maleic anhydride-modified styrene-based elastomer is more preferable, and a maleic anhydride-modified styrene / ethylene / butylene / styrene block copolymer is used. It is more preferable to have. By using these acid anhydride-modified styrene-based elastomers, the compatibility between the styrene-based elastomer and the polyester is increased, the compatibility between the polyester and the polyolefin is also improved, and the spinnability of the fiber is improved.

The acid anhydride-modified styrene-based elastomer preferably has an acid value of less than 25, more preferably 15 or less, and further preferably less than 10, from the viewpoint of further enhancing the compatibility between polyester and polyolefin. It is preferably 8 or less, and even more preferably. The acid anhydride-modified styrene-based elastomer is not particularly limited, but for example, from the viewpoint of ensuring compatibility with polyester, the acid value is preferably 0.5 or more, and preferably 1.0 or more. More preferably, it is more preferably 1.5 or more.

The polyolefin is not particularly limited, and may be, for example, a homopolymer of one kind of α-olefin or a copolymer of two or more kinds of α-olefin. Examples of α-olefins include ethylene, propylene, butene-1, penten-1, 4-methylpentene-1, hexene-1, 4-methylpentene-1, heptene-1, octene-1, nonene-1, and decene. -1, dodecene-1, and mixtures thereof can be mentioned. As the polyolefin, an olefin-based elastomer containing α-olefin and / or polyolefin as a main component, for example, containing 50% by mass or more of α-olefin and / or polyolefin may be used. The polyolefin is preferably one or more selected from the group consisting of polypropylene, polyethylene, polybutene-1, and polymethylpentene, more preferably polypropylene and / or polymethylpentene, and particularly preferably polypropylene.

The polypropylene is not particularly limited, and for example, a homopolymer, a copolymer, or a mixture thereof can be used. Examples of the copolymer include a copolymer of propylene and at least one α-olefin selected from the group consisting of ethylene and an α-olefin having 4 or more carbon atoms. The α-olefin having 4 or more carbon atoms is not particularly limited, and for example, butene-1, pentane-1, 3,3-dimethylbutene-1, 4-methylpentene-1, 4,4-dimethylpentene- 1. Decene-1, dodecene-1, tetradecene-1, octadecene-1, and the like can be mentioned. The copolymer may be a random copolymer or a block copolymer. The content of propylene in the copolymer is preferably 50 mol% or more. Among them, selected from the group consisting of propylene homopolymers, ethylene-propylene copolymers and ethylene-butene-1-propylene ternary copolymers from the viewpoint of spinnability, stability of spinning process, and dyeability of obtained fibers and threads. It is preferable that the amount is one or more, and a propylene copolymer is more preferable. One type of polypropylene may be used alone, or two or more types may be used in combination.

The polypropylene preferably has a melt mass flow rate (MFR) of 4 g / 10 minutes or more and 60 g / 10 minutes or less measured under the conditions of a temperature of 230 ° C. and a load of 21.2 N according to JIS K 7210. It is more preferably 10 minutes or more and 50 g / 10 minutes or less, and further preferably 6 g / 10 minutes or more and 40 g / 10 minutes or less. Within this range, there is no yarn breakage and stable spinning is easy.

The polyolefin preferably contains polypropylene in an amount of 70% by mass or more, more preferably 90% by mass or more, and particularly preferably substantially only polypropylene. The preferred upper limit is 100% by mass. Here, the term "substantially" is used because the resin provided as a product usually contains an additive component such as a stabilizer. Usually, the content of the additive is up to 15% by mass.

The polyolefin may contain a polyolefin other than polypropylene in a range of 30% by mass or less, preferably 10% by mass or less. Examples of other polyolefin components include polyethylene, polybutene-1, polymethylpentene and the like.

The polyolefin is not particularly limited, but from the viewpoint of spinning stability, the melting point is preferably 120 ° C. or higher and 240 ° C. or lower, more preferably 130 ° C. or higher and 220 ° C. or lower, and 140 ° C. or higher and 180 ° C. or lower. It is more preferable to have.

In the present invention, even if polyester is present as an island component in polyolefin such as polypropylene which is a sea component, the disperse dye can permeate the polyolefin such as polypropylene and diffuse into the polyester, so that the dyeability is good. It is presumed that the dyeing fastness is also improved.

The polyester may be a polycondensate of a dicarboxylic acid and / or an ester-forming derivative thereof and a diol and / or an ester-forming derivative thereof. Examples of the dicarboxylic acid include an aliphatic dicarboxylic acid, an alicyclic dicarboxylic acid, and an aromatic dicarboxylic acid. Examples of the diol include an aliphatic diol, an alicyclic diol, and an aromatic diol.

Examples of the aliphatic dicarboxylic acid include malonic acid, fumaric acid, maleic acid, succinic acid, itaconic acid, adipic acid, azelaic acid, sebacic acid, glutaric acid, 1,11-undecanedicarboxylic acid, and 1,12-dodecane. Examples thereof include dicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid and dimeric acid. Examples of the alicyclic dicarboxylic acid include 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, decalin-2,6-dicarboxylic acid and the like. Examples of the aromatic dicarboxylic acid include terephthalic acid, phthalic acid, isophthalic acid, 5-sodium sulfoisophthalic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,2'-biphenyldicarboxylic acid. , 3,3'-biphenyldicarboxylic acid, 4,4'-biphenyldicarboxylic acid, anthracendicarboxylic acid and the like.

Examples of the aliphatic diol include glycols such as ethylene glycol, trimethylene glycol, tetramethylene glycol, hexamethylene glycol, diethylene glycol, polyethylene glycol, polypropylene glycol and neopentyl glycol. Examples of the alicyclic diol include 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, spiroglycol, isosorbide and the like. Examples of the aromatic diol include catechol, naphthalene diol, bisphenol and the like.

The polyester has a high affinity with a styrene-based elastomer, has good compatibility with a polyolefin in the presence of the styrene-based elastomer, and improves interfacial adhesion and fine dispersibility. From the viewpoint, aromatic dicarboxylic acid and / or its It is preferably a polycondensate (aromatic polyester) of the ester-forming derivative and the aliphatic diol and / or the ester-forming derivative thereof. Further, from the viewpoint of good physical properties such as fiber strength, the polyester is preferably an aromatic polyester such as polyethylene terephthalate or polymethylene terephthalate. The polyethylene terephthalate may be a homopolymer of ethylene terephthalate containing terephthalic acid as a dicarboxylic acid and ethylene glycol as a diol component, or may be a copolymer containing ethylene terephthalate as a main component. Specifically, the copolymer contains terephthalic acid as a main dicarboxylic acid, ethylene glycol as a main diol component, and a diol component such as butanediol, isophthalic acid, and a dicarboxylic acid such as 2,6-naphthalenedicarboxylic acid. It may be polymerized. Polytrimethylene terephthalate may be a homopolymer of trimethylene terephthalate, and is a copolymer containing trimethylene terephthalate having terephthalic acid as a dicarboxylic acid and 1,3-propanediol as a diol component as a main component. There may be. Specifically, the copolymer contains terephthalic acid as the main dicarboxylic acid and 1,3-propanediol as the main diol component, and diol components such as ethylene glycol and butanediol, isophthalic acid, and 2,6-naphthalenedicarboxylic acid. Dicarboxylic acids and the like may be copolymerized.

The polyester is preferably a polyester obtained by copolymerizing an aliphatic dicarboxylic acid component. The polyester obtained by copolymerizing an aliphatic dicarboxylic acid component means a polyester containing an aliphatic dicarboxylic acid component as at least one of the dicarboxylic acid components.

In the polyester obtained by copolymerizing the aliphatic dicarboxylic acid component, the aliphatic dicarboxylic acid component is preferably an aliphatic dicarboxylic acid having 2 to 18 carbon atoms, and more preferably an aliphatic dicarboxylic acid having 2 to 10 carbon atoms. Examples of the aliphatic dicarboxylic acid include azelaic acid, succinic acid, adipic acid, sebacic acid, glutaric acid and the like. From a cost standpoint, adipic acid is preferred. Specific examples thereof include polyesters containing an aromatic dicarboxylic acid as a main dicarboxylic acid component and an aliphatic dicarboxylic acid having 2 to 18 carbon atoms as a copolymerized dicarboxylic acid component, and ethylene terephthalate from the viewpoint of fiber physical properties and cost. -Adipate copolymer, trimethylene terephthalate-adipate copolymer and the like are preferable.

As the polyester, for example, a polyester containing a repeating unit composed of a dicarboxylic acid component and a diol component shown below can be preferably used.
[Dicarboxylic acid component]
(1) Terephthalic acid is 50 mol% or more and 90 mol% or less (2) Sulfonic acid metal salt is 0.2 mol% or more and 6.0 mol% or less (3) Aliphatic dicarboxylic acid is 4.0 mol% or more 49. 8 mol% or less [diol component]
(1) Ethylene glycol is 50 mol% or more and 99.9 mol% or less (2) Diethylene glycol is 0.1 mol% or more and 50 mol% or less

The content of the terephthalic acid unit in the dicarboxylic acid component is 50 mol% or more and 90 mol% or less, preferably 84 mol% or more and 90 mol% or less. The larger the amount of terephthalic acid, the higher the mechanical strength of the obtained polyester itself tends to be.

Examples of the sulfonic acid metal salt include a metal salt of 5-sulfoisophthalic acid, a metal salt of 4-sulfoisophthalic acid, a metal salt of 4-sulfophthalic acid, and the like, and a metal salt of 5-sulfoisophthalic acid is preferable. As the metal ion, an alkali metal such as sodium, potassium and lithium, and an alkaline earth metal such as magnesium are preferable. A particularly preferred metal sulfonic acid salt is a sodium salt of 5-sulfoisophthalic acid (also referred to as 5-sodium sulfoisophthalate).

The content of the sulfonic acid metal salt unit in the dicarboxylic acid component is 0.2 mol% or more and 6.0 mol% or less, preferably 0.2 mol% or more and 1.0 mol% or less. Not only is this component relatively expensive, but when used in excess, it can make the polyester water soluble and can affect the physical properties of the resulting polyester itself.

The content of the aliphatic dicarboxylic acid unit in the dicarboxylic acid component is 4.0 mol% or more and 49.8 mol% or less, preferably 4.0 mol% or more and 15 mol% or less. When the content of the aliphatic dicarboxylic acid component is 4.0 mol% or more and 49.8 mol% or less, the crystallinity of the polyester is appropriately lowered and the dyeability is improved by appropriately lowering the glass transition temperature. In addition, instead of the aliphatic dicarboxylic acid, an ester-forming derivative such as a dimethyl ester of the aliphatic dicarboxylic acid can also be used.

Among the diol components, ethylene glycol is 50 mol% or more and 99.9 mol% or less, and diethylene glycol is 0.1 mol% or more and 50 mol% or less. When the diethylene glycol unit is 50 mol% or less, the single fiber strength of the fiber and the tensile strength of the spun yarn obtained by using the diethylene glycol unit can be increased. On the other hand, when the diethylene glycol unit is 0.1 mol% or more, the crystallinity of the polyester is likely to be appropriately lowered, and the dyeability is improved.

The polyester may be a cationic dye dyeable polyester modified so as to enhance dyeability with respect to the cationic dye. As the cationic dye dyeable polyester, a part of the dicarboxylic acid constituting the polyester is a sulfonic acid base represented by −SO ₃ X (1) (in the above formula (1), X is a metal ion and quaternary. Examples thereof include polyesters replaced with dicarboxylic acids substituted with phosphonium ions, cations forming one or more salts selected from the group consisting of quaternary ammonium ions and the like.). For example, an aromatic polyester obtained by copolymerizing an isophthalic acid component containing a sulfonic acid metal salt, an aromatic polyester obtained by copolymerizing an isophthalic acid component having a phosphonium sulfonate base, and the like can be mentioned.

The polyester is not particularly limited, but the glass transition temperature is preferably 20 ° C. or higher and 80 ° C. or lower. The polyester has a glass transition temperature of more preferably 42 ° C. or higher, still more preferably 44 ° C. or higher. The polyester has a glass transition temperature of more preferably 78 ° C. or lower, still more preferably 75 ° C. or lower. When the glass transition temperature of the polyester is 20 ° C. or higher, the crystallization of the first component containing the polyester becomes good, and the spinnability can be improved. When the glass transition temperature of the polyester is 80 ° C. or lower, the crystallinity of the first component containing the polyester becomes appropriate and the dyeability becomes good.

The polyester is not particularly limited, but from the viewpoint of spinnability, the melting point is preferably 180 ° C. or higher and 300 ° C. or lower. More preferably, the melting point of the polyester is 195 ° C. or higher, and even more preferably 210 ° C. or higher. Further, the melting point of the polyester is more preferably 290 ° C. or lower, further preferably 280 ° C. or lower.

The polyester is not particularly limited, but a polyester having an extreme viscosity [η] used for ordinary polyester fibers can be used. From the viewpoint of spinnability and fiber physical properties, in the case of polyethylene terephthalate, it is preferably 0.40 or more and 1.50 or less, more preferably 0.55 or more and 1.0 or less, and 0.58 or more and 0.70. The following is more preferable.

The dispersion diameter of the island component in the polymer alloy resin is not particularly limited, but is preferably 1 nm or more and 1000 nm or less, for example. When the dispersion diameter of the island component in the polymer alloy resin is 1 nm or more, it becomes easy to manufacture. The dispersion diameter of the island component in the polymer alloy resin may be 5 nm or more, 50 nm or more, or 100 nm or more. Further, when the dispersion diameter of the island component in the polymer alloy resin is 1000 nm or less, the boundary area of the sea-island interface can be increased to suppress the interfacial peeling at the time of fiberization and improve the dyeability. The dispersion diameter of the island component in the polymer alloy resin is more preferably 700 nm or less, further preferably 500 nm or less, and particularly preferably 300 nm or less.

In the first component, the fact that the polyolefin is a sea component and the polyester is an island component means that the content of the polyolefin is higher than the content of the polyester. When the polyolefin is a sea component, the dyeability is improved when the first component constitutes the sheath component, and the dyeing fastness is improved when the first component constitutes the core component. In the first component, the mass ratio of polyolefin / polyester is preferably 1.1 or more, and more preferably 1.2 or more. In the first component, the mass ratio of polyolefin / polyester is preferably 1.9 or less, and more preferably 1.8 or less, from the viewpoint of improving dyeability.

The first component contains 10 parts by mass of a styrene-based elastomer with respect to 100 parts by mass of polyester from the viewpoint of enhancing the dispersibility of polyester in polyolefin and the affinity with resin and enhancing the interfacial adhesiveness between polyolefin and polyester. It is preferably contained in an amount of 60 parts by mass or less (0.1 or more and 0.6 or less in terms of mass ratio), and more preferably 20 parts by mass or more and 40 parts by mass or less (0.2 or more and 0.4 or less in mass ratio).

The first component may contain a small amount of other thermoplastic resin or additive in addition to the above-mentioned polyolefin, polyester and styrene-based elastomer as long as the object of the present invention is not impaired. Examples of the additive include antistatic agents, pigments, matting agents, heat stabilizers, light stabilizers, flame retardants, antibacterial agents, lubricants, plasticizers, softeners, antioxidants, ultraviolet absorbers and the like. Be done. The other thermoplastic resin and additives are preferably contained in an amount of 10% by mass or less based on the total mass of the first component.

(Second component)
The second component contains polyolefin. As the polyolefin in the second component, the polyolefins listed as those used in the first component can be appropriately used. The polyolefin used for the first component and the polyolefin used for the second component may be the same or different, but they are the same from the viewpoint of enhancing the interfacial adhesiveness between the first component and the second component. It is preferable that it is one.

The second component may contain a small amount of other thermoplastic resin or additive in addition to the above-mentioned polyolefin as long as the object of the present invention is not impaired. Examples of the additive include antistatic agents, pigments, matting agents, heat stabilizers, light stabilizers, flame retardants, antibacterial agents, lubricants, plasticizers, softeners, antioxidants, ultraviolet absorbers and the like. Be done. The other thermoplastic resin and additives are preferably contained in an amount of 10% by mass or less based on the total mass of the second component.

In the core-sheath type polymer alloy fiber, one of the first component and the second component is the core component, and the other is the sheath component. The first component may constitute a sheath component, the second component may form a core component, the first component may form a core component, and the second component may form a sheath component. The first component contains a polymer alloy having a sea-island structure containing polyolefin as a sea component and polyester as an island component, and the island components are discontinuously dispersed in the length direction of the fiber.

FIG. 1 is a cross-sectional view of a core-sheath polymer alloy fiber according to one or more embodiments of the present invention. FIG. 1A is a cross-sectional view of a core-sheath type polymer alloy fiber when the first component constitutes a sheath component and the second component constitutes a core component. The core-sheath type polymer alloy fiber 1 of the embodiment has a sheath component 2 composed of a first component containing a polymer alloy and a core component 3 composed of a second component containing a polyolefin. The sheath component 2 contains polyolefin as the sea component 4 and polyester as the island component 5, and the island component 5 is discontinuously dispersed in the fiber length direction. By forming the sheath component 2 with the first component containing the polymer alloy containing polyester as the island component 5, the core-sheath type polymer alloy fiber 1 of the embodiment has improved dyeability. Further, since the sea component 4 contains polyolefin, light weight, abrasion resistance, heat retention and water repellency are improved. Since the first component contains a styrene-based elastomer having a weight average molecular weight (Mw) of 100,000 or more as a compatibilizer, the styrene-based elastomer is composed of only polyolefin in the sheath component 2 composed of the first component. It exists in the region, the region consisting only of the polyester, and the interface between the polyolefin and the polyester, and the compatibility between the polyolefin and the polyester in the sheath component 2 is improved, the interfacial adhesiveness between the polyolefin and the polyester is improved, and the sheath component 2 is present. The interfacial adhesiveness between the core component 3 and the core component 3 is also improved, and the core-sheath type polymer polyolefin fiber can be stably spun with almost no thread breakage.

FIG. 1B is a cross-sectional view of a core-sheath type polymer alloy fiber when the first component constitutes a core component and the second component constitutes a sheath component. The core-sheath type polymer alloy fiber 11 of the embodiment has a sheath component 13 composed of a second component containing polyolefin and a core component 12 composed of a first component containing a polymer alloy. The core component 12 contains polyolefin as the sea component 14 and polyester as the island component 15, and the island component 15 is discontinuously dispersed in the fiber length direction. By configuring the core component 12 with the first component containing the polymer alloy containing polyester as the island component 15, the core-sheath type polymer alloy fiber 11 of the embodiment has improved dyeing fastness. Further, since both the sea component 14 and the sheath component 13 contain polyolefin, lightness, abrasion resistance, heat retention and water repellency are improved. Since the first component contains a styrene-based elastomer having a weight average molecular weight (Mw) of 100,000 or more as a compatibilizer, the styrene-based elastomer is composed of only polyolefin in the core component 12 composed of the first component. It exists in the region, the region consisting only of polyester, and the interface between polyolefin and polyester, and the compatibility between polyolefin and polyester in the core component 12 is improved, the interfacial adhesiveness between polyolefin and polyester is improved, and the sheath component 13 is used. The interfacial adhesiveness between the core component 12 and the core component 12 is also improved, and the core-sheath type polymer polyolefin fiber can be stably spun with almost no thread breakage.

FIG. 1 is a schematic view of a cross section of a core-sheath type polymer alloy fiber when the fiber cross section is circular. However, in the present invention, the shape of the fiber cross section of the core-sheath type polymer alloy fiber is not particularly limited and is not circular. The shape may be, for example, an elliptical shape, a Y shape, an X shape, a well shape, a polygonal shape, a star shape, a multi-leaf shape having 3 or more and 32 or less convex parts, and the like. It may be a so-called hollow fiber having a hollow portion continuous in the length direction in a part of the fiber cross section.

In the core-sheath type polymer alloy fiber, the composite ratio (core-sheath ratio) of the core component and the sheath component is preferably, for example, 20/80 or more and 80/20 or less in terms of the core / sheath mass ratio, and is 30 /. It is more preferably 70 or more and 70/30 or less, and further preferably 40/60 or more and 60/40 or less. When the core-sheath ratio is within the above-mentioned range, the spinnability of the core-sheath type polymer alloy fiber is improved and the dyeability is also improved.

From the viewpoint of improving dyeability and dyeing fastness of the core-sheath type polymer alloy fiber, it is preferable that the core-sheath type polymer alloy fiber contains 7.5% by mass or more of polyester with respect to the total mass of the core-sheath type polymer alloy fiber, and 8.0. It is more preferably contained in an amount of mass% or more, and further preferably contained in an amount of 8.5% by mass or more. Further, the core-sheath type polymer alloy fiber preferably contains 30% by mass or less of polyester with respect to the total mass of the core-sheath type polymer alloy fiber from the viewpoint of light weight, abrasion resistance, heat retention and water repellency. , 25% by mass or less is more preferable, and 20% by mass or less is further preferable.

Since the core-sheath type polymer alloy fiber contains polyester as an island component, it can be dyed with a disperse dye and / or a cationic dye. If it is a disperse dye and / or a cationic dye, dyed products of various colors can be obtained, and deep dyeing is also possible. From the viewpoint of versatility, it is preferable that the core-sheath type polymer alloy fiber is dyed with a disperse dye.

Hereinafter, a method for producing a core-sheath type polymer alloy fiber of the present invention will be described. The method for producing the core-sheath type polymer alloy fiber is not particularly limited, and for example, polyester as an island component and weight average molecular weight (Mw) as a compatibilizer are 100,000 or more in polyolefin as a sea component. A first component containing a polymer alloy in which a certain styrene-based elastomer is dispersed and a second component containing a polyolefin are melt-extruded using a core-sheath type nozzle to obtain a spun filament (also referred to as an undrawn filament). Including a step (hereinafter, also referred to as a spinning step). As the first component and the second component, those described above can be appropriately used.

The polymer alloy may be produced, for example, by a method in which polyester, polyolefin, and styrene-based elastomer are dry-blended and then melt-kneaded using various general kneaders. Polyester, polyolefin, and styrene-based elastomer may be produced. After dry blending, it may be directly put into a spinning machine and mixed in the spinning machine flow path. From the viewpoint of easily dispersing the polyester in the polyolefin, it is preferable to prepare the polyester by a method of melt-kneading using a kneader. Examples of the kneader include a single-screw extruder and a twin-screw kneading extruder, a roll mixer, a Banbury mixer and the like, but a twin-screw kneading extruder is preferable from the viewpoint of workability and kneading property.

In the spinning step, the spinning temperature of the first component and the second component may be Tm or more when the melting point of the polyester is Tm, and is not particularly limited, but from the viewpoint of improving the stability of spinning, the polymer alloy is used. The spinning temperature of the first component contained is preferably Tm or more and Tm + 15 ° C. or lower, and the spinning temperature of both the first component and the second component is more preferably Tm or more and Tm + 15 ° C. or lower.

The spun filament is preferably stretched to a predetermined fineness. The stretching treatment may be wet stretching or dry stretching. Wet stretching can be performed, for example, in a water bath at room temperature (for example, 25 ° C.) or higher and 100 ° C. or lower, preferably in a water bath at 50 ° C. or higher and 90 ° C. or lower, and more preferably 60 ° C. or higher and 90 ° C. or lower. it can. From the viewpoint of keeping the physical properties of the fiber, particularly the elongation in an appropriate range, the stretching treatment is preferably dry stretching. Dry stretching can be performed in dry air or using a heated metal roll. The temperature in the dry stretching is preferably 100 ° C. or higher and 150 ° C. or lower, more preferably 110 ° C. or higher, and further preferably 120 ° C. or higher. When the stretching treatment is performed under the above conditions, the spun filament can be sufficiently stretched and the hydrolysis of the polyester component can be suppressed. From the viewpoint of suppressing the peeling of the core component and the sheath component, the draw ratio is preferably 1.3 times or more and 6.5 times or less, and more preferably 1.5 times or more and 6.0 times or less.

The drawn filament is preferably crimped from the viewpoint of enhancing the card-passability when used as a short fiber. The crimping is not particularly limited, but can be applied using, for example, a known crimping machine such as a stuffing box type crimper.

It is advisable to apply the fiber treatment agent to the fiber surface before or after applying the crimp. Preferably, after applying the fiber treatment agent to the fiber surface, crimping is applied. Then it is good to dry. When the core-sheath type polymer alloy fiber is used for a spun yarn or a non-woven fabric, it is dried and then cut to a predetermined fiber length to obtain a short fiber. When the core-sheath type polymer alloy fiber is also used as a filament, it is dried and then wound as it is.

The fiber length of the core-sheath type polymer alloy fiber is not particularly limited, and may be a short fiber or a long fiber. The core-sheath type polymer alloy fiber is cut to a fiber length suitable for the intended use, and can be cut to a fiber length of 1 mm or more and 110 mm or less, for example. When the core-sheath type polymer alloy fiber is used for the spun yarn, the fiber length is preferably 24 mm or more and 75 mm or less, more preferably 28 mm or more and 65 mm or less, and further preferably 32 mm or more and 54 mm or less. It is particularly preferable that the thickness is 34 mm or more and 48 mm or less. When the core-sheath type polymer alloy fiber is used as a non-woven fabric, the fiber length is preferably 20 mm or more and 80 mm or less, more preferably 30 mm or more and 75 mm or less, further preferably 35 mm or more and 65 mm or less, and 40 mm. It is particularly preferable that the thickness is 55 mm or more. When the core-sheath type polymer alloy fiber is used as a stuffing cotton material such as a cushion material filled with short fibers, the fiber length is preferably 10 mm or more and 80 mm or less, and 20 mm or more and 75 mm or less. Is more preferable, and 30 mm or more and 70 mm or less is particularly preferable.

The core-sheath type polymer alloy fiber preferably has a single fiber strength of 1.5 cN / dtex or more and 5.0 cN / dtex or less, and more preferably 1.6 cN / dtex or more and 4.8 cN / dtex or less. When the single fiber strength is 1.5 cN / dtex or more, the fiber is hard to break even if it receives an external force (for example, spinning tension) when processing the fiber. Further, when the single fiber strength is 5.0 cN / dtex or less, the anti-pilling property of the fiber becomes good.

The core-sheath type polymer alloy fiber preferably has an elongation of 10% or more and 75% or less, more preferably 15% or more and 70% or less, and further preferably 20% or more and 45% or less. It is particularly preferable that it is 20% or more and 40% or less. When the elongation is within the above-mentioned range, the fiber has a low elongation within a range that does not impair the texture of the fiber structure, and the processability and productivity in the spinning process are likely to be improved.

The core-sheath type polymer alloy fiber preferably has a single fiber fineness of 0.4 dtex or more and 20 dtex or less. If the single fiber fineness is within the above-mentioned range, various fiber structures, for example, spun yarn containing the core-sheath polymer alloy fiber can be used to make a woven or knitted fabric by utilizing the characteristics of the core-sheath type polymer alloy fiber. The core-sheath type polymer alloy fiber can be used as various stuffed cotton materials, or various non-woven fabrics containing the core-sheath type polymer alloy fiber can be used. In particular, a woven or knitted fabric produced by using a spun yarn containing a core-sheath type polymer alloy fiber having a single fiber fineness in the above-mentioned range becomes flexible and is suitable for clothing and the like. When the spun yarn is composed of the core-sheath type polymer alloy fiber, the single fiber fineness is more preferably 0.4 dtex or more and 3.5 dtex or less, further preferably 0.6 dtex or more and 2.5 dtex or less, and 0. It is particularly preferable that it is 8.8 dtex or more and 2.0 dtex or less.

Next, the fiber structure of the present invention will be described. The fiber structure includes the core-sheath type polymer alloy fiber. The fiber structure may be composed of only core-sheath type polymer alloy fibers (100% by mass), or may contain other fibers in addition to the core-sheath type polymer alloy fibers. The fiber structure preferably contains 10% by mass or more and 100% by mass or less of core-sheath type polymer alloy fibers, and 90% by mass or less of other fibers. Within this range, the characteristics of the core-sheath type polymer alloy fiber can be utilized.

As other fibers, for example, natural fibers, regenerated fibers, purified cellulose fibers, semi-synthetic fibers, and synthetic fibers can be used. Examples of natural fibers include cotton, silk, wool, hemp, cashmere and the like. Examples of the recycled fiber include rayon, cupra and the like. Examples of the purified cellulose fiber include tencel and lyocell. Examples of the semi-synthetic fiber include acetate and triacetate. Examples of the synthetic fiber include acrylic fiber, polyester fiber, polyolefin fiber, nylon fiber, acrylate fiber, ethylene vinyl alcohol fiber, urethane fiber and the like. As the other fiber, one type or two or more types of fibers can be appropriately selected from the above-mentioned fibers depending on the intended use and the like.

Examples of the fiber structure include threads, woven fabrics, knitted fabrics, non-woven fabrics, stuffed cotton and textile products.

For the combined use or mixing with other fibers, for example, the following method can be adopted.
(1) Blended spinning: Blended spinning is a mixture of two or more kinds of fibers at the cotton stage. For example, mixing with mixed cotton, curd, kneading, sliver, etc. It is mainly used for uniform mixing of yarn and non-woven fabric.
(2) Synthetic yarn: Synthetic yarn is a mixture of two or more kinds of yarns twisted together. For example, in the case of twin yarn, it is a mixture in which the fiber yarn of the present invention and another fiber yarn are twisted together. It is used for twisting spun yarns, spun yarns and filament yarns, and filament yarns.
(3) Mixed fiber: The mixed fiber is used when the fibers of the filament yarns are mixed.
(4) Mixed weaving: Mixed weaving is a mixture in which a plurality of types of threads constituting a woven fabric are used to form a woven fabric. For example, different types of warp and weft may be used, or a plurality of types of warp and weft may be used.
(5) Cross-knitting: Cross-knitting is a mixture when a plurality of types of yarns are used in manufacturing a knitted fabric.
(6) Non-woven fabric: Multiple types of fiber layers laminated by a web forming method such as a card method, an airlaid method, a wet papermaking method in the case of short fibers, and a web forming method by a spunbond method, a melt blow method, etc. in the case of long fibers. To mix.

The yarn can be produced by any method such as a ring method, an open-ended method, a binding method, an alternating twisting method, a wrapping method, a vortex flow method (MVS method), or a non-twisting method. In this case, the preferred count is an English cotton count in the range of 5S or more and 100S or less. You may use a single yarn or twist multiple yarns together. When the fiber structure is a spun yarn, the single fiber fineness of the core-sheath type polymer alloy fiber constituting the spun yarn is preferably 3.5 dtex or less. If the single fiber fineness of the core-sheath type polymer alloy fiber is within the above range, it is easy to manufacture a spun yarn. More preferably, the single fiber fineness of the core-sheath type polymer alloy fiber constituting the spun yarn is 0.4 dtex or more and 3.5 dtex or less, more preferably 0.6 dtex or more and 2.5 dtex or less, and particularly preferably 0. It is 8 dtex or more and 2.0 dtex or less.

The yarn preferably contains the core-sheath type polymer alloy fiber in an amount of 10% by mass or more, more preferably 20% by mass or more, and further preferably 50% by mass or more. The thread may be composed of 100% by mass of the core-sheath type polymer alloy fiber. The yarn containing 10% by mass or more of the core-sheath type polymer alloy fiber is excellent in dyeability, dyeing fastness, heat retention, quick-drying property and light weight.

In addition to the core-sheath type polymer alloy fiber, the yarn may contain other fibers in a range of 90% by mass or less, preferably 80% by mass or less, and more preferably 50% by mass or less. For example, when a core-sheath type polymer alloy fiber having a relatively low single fiber strength is used for the yarn, it is preferable to blend it with other fibers in order to increase the strength of the entire yarn. The other fibers are not particularly limited, but may be the fibers listed in the other fibers mentioned above, and among them, one selected from the group consisting of acrylic fibers, polyester fibers, and cellulosic fibers. Is preferable. Acrylic fibers and polyester fibers are excellent in dyeability, washing fastness and strength, and thus give strength to yarn without impairing the characteristics of core-sheath type polymer alloy fibers. Cellulose-based fibers such as cotton and rayon are excellent in dyeability, washing fastness, and unique texture and water absorption derived from nature. Therefore, in combination with the characteristics of core-sheath type polymer alloy fibers, new functions and tactile sensations are achieved. give.

The number of fibers constituting the yarn is preferably 90 or more, and more preferably 100 or more. The preferred upper limit is 500 or less. When the number of fibers constituting the yarn is 90 or more, it is difficult for the yarn to break in the spinning process or the winding process.

When the fiber structure is a knitted fabric, the structure, basis weight, density and the like are not particularly limited, and may be any of flat knitting, rubber knitting, double-sided knitting and the like. Moreover, the fiber structure may be a woven fabric.

When the fiber structure is a woven or knitted fabric, it preferably contains 10% by mass or more of the yarn containing the core-sheath type polymer alloy fiber, more preferably 20% by mass or more, and further preferably 30% by mass or more. .. The woven or knitted fabric may be made of 100% by mass of core-sheath type polymer alloy fibers. Such woven and knitted fabrics are excellent in dyeability, dyeing fastness, heat retention, quick-drying property and light weight.

The woven or knitted fabric preferably comprises a yarn containing the core-sheath type polymer alloy fiber and a yarn of another fiber. In this case, the woven or knitted fabric may contain other fibers (threads of other fibers) in a range of 90% by mass or less, preferably in a range of 80% by mass or less, and more preferably in a range of 70% by mass or less. Good. The form of the other fiber may be any form such as a spun yarn, a monofilament yarn, and a multifilament yarn. The other fiber may be the fiber mentioned in the other fibers described above, and among them, polyester fiber or urethane fiber is preferable. Since the polyester fiber is excellent in dyeability, washing fastness and strength, it gives strength to the yarn without impairing the characteristics of the core-sheath type polymer alloy fiber. Further, since the urethane fiber has excellent elasticity and contracts gently, it is possible to obtain a woven or knitted fabric having stretchability while taking advantage of the soft texture of the core-sheath type polymer alloy fiber.

The textile structure also includes textile products such as clothing, bedding side areas, blankets, rugs, and carpets. Examples of clothing include underwear, underwear, shirts, jumpers, sweaters, pants, training wear, tights, abdominal wraps, mufflers, hats, gloves, socks, earmuffs, and the like. It is also suitable for winter clothing, sportswear, stuffed cotton for clothing, and the like. Further, the surface of the fabric may be brushed like a fleece.

The fiber structure can be dyed with disperse dyes and / cationic dyes. In the case of a disperse dye, a dyed product dyed in a desired color can be obtained by dyeing in a temperature range of 110 ° C. or higher and 130 ° C. or lower.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

The measurement / evaluation methods used in the examples and comparative examples are as follows.
(1) Polypropylene melt mass flow rate (MFR)
The measurement was carried out under the conditions of a temperature of 230 ° C. and a load of 21.2 N according to JIS K 7210.
(2) Extreme Viscosity of Polyester According to JIS K 7637-5, 1 g of polyester was dissolved in 100 ml of a mixed solvent of phenol / 1,1,2,2-tetrachloroethane = 6/4 (mass ratio), and Ubbelohde at 30 ° C. It was measured using a mold viscometer.
(3) Acid value of styrene-based elastomer Measured according to JIS K 0070 (1992).
(4) Single fiber strength and elongation According to JIS L 1015, the load value and elongation at the time of fiber cutting when the tensile speed is set to 20 mm / min and the sample gripping interval is set to 20 mm using a tensile tester. Was measured and used as the strength and elongation of the single fiber, respectively.
(5) Single fiber fineness Measured according to JIS L 1015.
(6) Spinability The spinnability was evaluated according to the following three criteria.
A: During the 2 hours of spinning, we were able to spin without yarn breakage.
B: During spinning for 2 hours, yarn breakage occurred 1 to 4 times.
C: Thread breakage occurred frequently and spinning was not possible.
(7) Dyeability The dyeability was evaluated according to the following three-step criteria.
A: There is no or almost no undyed white part.
B: There are a few unstained white areas.
C: Undyed white areas stand out.
(8) Dyeing fastness Dyeing fastness was evaluated for each of the following items based on the evaluation criteria of the Boken Quality Evaluation Organization.
Color crying (class): According to the Daimaru method, the presence or absence of color transfer due to water wetting was judged.
Light fastness: The degree of fading due to light (strong ultraviolet rays) was determined according to JIS L 0842.
Washing fastness: According to JIS L 0844 A-2, the presence or absence of color fading and color transfer due to washing was judged.
Sweat fastness: According to JIS L 0844 (acidic / alkaline), the presence or absence of color fading and color transfer due to sweat was determined.
Friction fastness: According to JIS L 0849 type II, color transfer when rubbed in a dry state or a wet state was judged.
Sublimation fastness: According to JIS L 0854, the presence or absence of color fading and color transfer due to ironing was determined.

The resins used in Examples and Comparative Examples were as follows.
(1) Polyolefin: Propylene homopolymer, MFR: 30 g / 10 minutes (230 ° C., 21.2 N), melting point 160 ° C., manufactured by Japan Polypropylene Corporation, trade name "SA03", hereinafter also referred to as "PP".
(2) Polyolefin: Maleic anhydride-modified propylene homopolymer, Maleic anhydride: Acid value 21.7, MFR: 45 g / 10 minutes (180 ° C, 21.2 N), Melting point: 150 ° C, Mitsui Chemicals Co., Ltd. Made by, trade name "Modic P908", hereinafter also referred to as "M-PP".
(3) Polyester: Polyethylene terephthalate homopolymer (polyethylene terephthalate), melting point 250 ° C, glass transition temperature 69 ° C, manufactured by Toray Industries, Inc., trade name "T200E", ultimate viscosity [η]: 0.64, or less , Also referred to as "PET".
(4) Polyester: Ethylene terephthalate-adipate copolymer, melting point 235 ° C., glass transition temperature 45 ° C., ultimate viscosity [η]: 0.63, manufactured by DuPont, USA, product name "APEXA4027", hereinafter "PES-1" It is also written.
(5) Polyester: 5-sodium sulfoisophthalate copolymerized polyethylene terephthalate (cationic dye dyeable PET), melting point 241 ° C., glass transition temperature 65 ° C., Woongjin Chemical Co., Ltd. Ltd. Manufactured, Extreme Viscosity [η]: 0.63, hereinafter also referred to as "PES-2".
(6)) Polyester: homopolymer of trimethylene terephthalate (polytrimethylene terephthalate), melting point 228 ° C, glass transition temperature 50 ° C, manufactured by DuPont in the United States, product name "Sorona", extreme viscosity [η]: 0.92 , Hereinafter, also referred to as "PTT".
(7) Styrene-based elastomer: maleic anhydride-modified SEBS, number average molecular weight (Mn) 64,200, weight average molecular weight (Mw) 124,000, z average molecular weight (Mz) 173,000, styrene block content 12% by mass , Acidity of 4, below, will be referred to as "M-SEBS1".
(8) Styrene-based elastomer: maleic anhydride-modified SEBS, number average molecular weight (Mn) 52,700, weight average molecular weight (Mw) 82,500, z average molecular weight (Mz) 112,000, styrene block content 20% by mass , Acid value 10 and below, also referred to as "M-SEBS2".
(9) Styrene-based elastomer: maleic anhydride-modified SEBS, number average molecular weight (Mn) 43,600, weight average molecular weight (Mw) 65,600, z average molecular weight (Mz) 91,400, styrene block content 30% by mass , Acidity of 10, and below, also referred to as "M-SEBS3".

(Examples 1 to 3)
<Manufacturing of polymer alloy>
The polyolefins, polyesters and styrene-based elastomers shown in Table 1 below were mixed at the blending ratios shown in Table 1 below, and kneaded at 240 to 270 ° C. with a twin-screw kneading extruder. The strands discharged from the twin-screw kneading extruder were water-cooled and then cut to about 3 mm with a pelletizer to obtain polymer alloy pellets.
<Preparation of core-sheath type polymer alloy fiber>
In Examples 1 and 3, the polymer alloy obtained above was used as the core component, the polyolefin shown in Table 1 below was used as the sheath component, and in Example 2, the polymer alloy obtained above was used as the sheath component, and the table below was used. Using the polyolefin shown in 1 as the core component, composite spinning was performed under the spinning conditions shown in Table 1 below to obtain a core-sheath type spun filament (undrawn filament), and then stretching was performed under the stretching conditions shown in Table 1 below. , Stretched filaments were obtained. Then, a fiber treatment agent was applied to the fiber surface, crimping was applied with a stuffing box type crimper, and the fiber was dried with hot air at 110 ° C. for 15 minutes. After drying, it was cut to a predetermined length to obtain a core-sheath type polymer alloy fiber.
<Making non-woven fabric>
A core-sheath type polymer alloy fiber cut to a predetermined length is opened with a parallel card machine to prepare a card web, and the card web is subjected to needle punching treatment and then water flow confounding treatment. The non-woven fabric having a basis weight of about 100 g / m ² was obtained by drying.
<Dyeing process>
Dispersion dye (Kayalon (registered trademark) Polyester Black manufactured by Nippon Kayaku Co., Ltd.): 8% owf (owf stands for on the weight of fiber), dyeing aid: 2 g / L, acetic acid: The dyeing solution was adjusted to 0.5 cc / L and a bath ratio of 1:15, and dyed at 120 ° C. for 1 hour.
The non-woven fabric dyed under the above dyeing conditions was subjected to reduction cleaning. For reduction cleaning, hydrosulfite (sodium dithionite): 2 g / L, sodium hydroxide (38Be): 4.5 cc / L, soaping agent: 2.5 g / L, bath ratio 1:15. The mixture was adjusted and reduced and washed at 80 ° C. for 20 minutes.
After the reduction washing was completed, the mixture was thoroughly washed with water and dried.

(Examples 4 to 6)
<Manufacturing of polymer alloy>
Similar to Example 1, polyolefins, polyesters and styrene-based elastomers are mixed in a blending ratio of 55% by mass of polyolefin, 35% by mass of polyester and 10% by mass of styrene-based elastomer, and 240 by a twin-screw kneading extruder. Kneading was performed at ~ 270 ° C. The strands discharged from the twin-screw kneading extruder were water-cooled and then cut to about 3 mm with a pelletizer to obtain polymer alloy pellets.
<Preparation of core-sheath type polymer alloy fiber>
Polymer alloy and PP were mixed so that the core components had the ratio shown in Table 1 below, and spinning was performed while kneading at the indicated barrel temperature with a uniaxial kneading extruder. A core-sheath type composite polymer alloy fiber was obtained in the same manner as in Example 1 except for the above.
<Making non-woven fabric>
A non-woven fabric using the core-sheath type composite polymer alloy fiber was produced in the same manner as in Example 1 except that the polymer alloy obtained above was used.
<Dyeing process>
The dyeing treatment was carried out in the same manner as in Example 1 except that the non-woven fabric obtained above was used.

In the examples, wet stretching was carried out in a water bath at the temperatures shown in Table 1 below, and dry stretching was carried out using a metal roll heated to the temperatures shown in Table 1 below.

(Comparative Examples 1 to 6)
<Manufacturing of polymer alloy>
The polyolefins, polyesters and styrene-based elastomers shown in Table 2 below were mixed at the blending ratios shown in Table 2 below, and kneaded at 240 to 270 ° C. with a twin-screw kneading extruder. The strands discharged from the twin-screw kneading extruder were water-cooled and then cut to about 3 mm with a pelletizer to obtain polymer alloy pellets.
<Preparation of core-sheath type polymer alloy fiber>
When the polymer alloy obtained above was used as the core component and the polyolefin shown in Table 2 below was used as the sheath component and composite spinning was performed under the spinning conditions shown in Table 2 below, yarn breakage occurred frequently and spinning was possible. could not.

The physical properties of the core-sheath type polymer alloy fibers obtained in Examples 1 to 6 were measured as described above, and the results are shown in Table 1 below. The non-woven fabrics obtained in Examples 1 to 6 were used to evaluate dyeability and dye fastness, and the results are shown in Table 1 below.

As can be seen from the results in Table 1, in the examples, the yarn could be spun stably with almost no yarn breakage, and the obtained core-sheath type polymer alloy fiber had good dyeability and dyeing fastness. Further, when the cross section of the fiber of the example was observed, in Examples 1, 3 to 6, the fiber had a core component and a sheath component, that is, a core-sheath structure, and the core component was a sea component. It has an island component, and the island component is discontinuously dispersed in the length direction of the fiber. In Example 2, the fiber has a core component and a sheath component, that is, has a core-sheath structure and a sheath component. Had a sea component and an island component, and the island component was discontinuously dispersed in the length direction of the fiber. Further, from the comparison between Examples 1, 5 and 6 and Examples 2 to 4, fibers having better physical properties such as elongation can be obtained by dry stretching at a temperature of 105 ° C. or higher and 155 ° C. or lower. I understood.

On the other hand, in Comparative Examples 1 to 5 using maleic anhydride-modified SEBS having a weight average molecular weight (Mw) of less than 100,000 as a styrene-based elastomer, a polymer alloy could be obtained, but the spinnability was poor and fibrosis was achieved. Couldn't. Further, in Comparative Example 6 using the ethylene terephthalate-adipate copolymer and the maleic anhydride-modified propylene homopolymer, a polymer alloy could be obtained, but the spinnability was poor and the fiber could not be formed.

1,11 Core-sheath type polymer alloy fiber 2,12 First component (polymer alloy)
3,13 Second component 4,14 Sea component 5,15 Island component

Claims (16)

The first component of either the core component or the sheath component contains a polyolefin as a sea component, a polyester as an island component, and a polymer alloy in which the island component is discontinuously dispersed in the length direction of the fiber. In a core-sheath polymer alloy fiber in which the other second component of the core component and the sheath component contains polyolefin,
The polymer alloy contains a styrene-based elastomer, and the styrene-based elastomer is a core-sheath type polymer alloy fiber having a weight average molecular weight (Mw) of 100,000 or more. The core-sheath type polymer alloy fiber according to claim 1, wherein the core component is composed of the first component and the sheath component is composed of the second component. The core-sheath type polymer alloy fiber according to claim 1 or 2, wherein the styrene-based elastomer contains less than 15% by mass of a styrene block. The core-sheath polymer alloy fiber according to any one of claims 1 to 3, wherein the styrene-based elastomer is a styrene-ethylene-butylene-styrene (SEBS) block copolymer. The core-sheath type polymer alloy fiber according to any one of claims 1 to 4, wherein the styrene-based elastomer is a maleic anhydride-modified styrene-based elastomer. The core-sheath type polymer alloy fiber according to claim 5, wherein the styrene-based elastomer has an acid value of less than 10. The core sheath according to any one of claims 1 to 6, wherein in the alloy resin, the mass ratio of the polyester to the styrene-based elastomer (styrene-based elastomer mass / polyester mass) is 0.1 or more and 0.6 or less. Molded polymer alloy fiber. The core-sheath polymer alloy according to any one of claims 1 to 7, wherein the content of the polyester is 7.5% by mass or more and 30% by mass or less with respect to the total mass of the core-sheath type polymer alloy fiber. fiber. The polyester contains polyethylene terephthalate, polytrimethylene terephthalate, an aromatic dicarboxylic acid as a main dicarboxylic acid component, and an aliphatic dicarboxylic acid having 2 to 18 carbon atoms as a copolymerized dicarboxylic acid component, and a cationic dye dyeable polyester. The core-sheath type polymer alloy fiber according to any one of claims 1 to 8, which is one or more selected from the group consisting of. The core-sheath type polymer alloy fiber according to claim 9, wherein the polyester is one or more selected from the group consisting of polyethylene terephthalate and cation dye dyeable polyester. The core-sheath type polymer alloy fiber according to any one of claims 1 to 10, wherein the core-sheath type polymer alloy fiber is dyed with a disperse dye. A fiber structure containing the core-sheath type polymer alloy fiber according to any one of claims 1 to 11. The fibrous structure according to claim 12, wherein the fibrous structure is at least one selected from the group consisting of yarn, woven fabric, knitted fabric, non-woven fabric, stuffed cotton and textile products. The fiber assembly according to claim 12 or 13, wherein the fiber structure is a spun yarn, and the core-sheath type polymer alloy fiber constituting the spun yarn has a fineness of 2.0 dtex or less. A first component containing a polymer alloy containing polyolefin as a sea component, polyester as an island component, and a styrene-based elastomer having a weight average molecular weight (Mw) of 100,000 or more as a compatibilizer, and a second component containing polyolefin. The component is melt-extruded using a core-sheath type nozzle to obtain a spun filament.
A method for producing a core-sheath type polymer alloy fiber, wherein the spinning temperature of the first component containing the polymer alloy is Tm or more and Tm + 15 ° C. or less when the melting point of the polyester is Tm. Further, it includes a step of dry-drawing the spun filament and a step of imparting crimp to the obtained drawn filament.
The method for producing a core-sheath type polymer alloy fiber according to claim 15, wherein the stretching temperature in the dry drawing is 100 ° C. or higher and 155 ° C. or lower.