JP6722032B2 - Spun yarn containing polyolefin multilayer filaments - Google Patents

Description

The present invention relates to a multi-layer filament composed of polyolefin and its use.

Fibers such as filaments are widely used in clothing fields such as innerwear, outerwear and stockings, sports fields such as swimwear and tights, hygiene materials fields such as diapers, and industrial materials fields.

In recent years, in particular, flexible fibers used in the fields of sports, clothing and sanitary materials are strongly required to have high elasticity and high functionality represented by thinness, lightness and transparency. Elastic fibers of polyamide, polyester or polyurethane have been widely used in these fields (for example, Patent Documents 1 to 3).
On the other hand, a filament obtained by using a polyolefin resin as a raw material has a feature that it is light in weight and low in water absorption, but has a problem in flexibility, as compared with a filament obtained by using the above resin. In order to solve such a problem, a monofilament (Patent Document 4) and a 4-methyl-1-pentene copolymer formed by spinning a resin material containing an ethylene-based copolymer satisfying specific requirements and further stretching are spun. A spun yarn (Patent Document 5) obtained by the above is disclosed.

Japanese Patent Laid-Open No. 11-323659 JP, 11-222724, A JP, 2008-248137, A JP, 2004-323983, A JP, 2014-167185, A

The fibers disclosed in Patent Documents 1 to 3 have a problem of dimensional change due to deterioration due to water absorption or hydrolysis, and when processed into wear or the like, they have a strong feeling of tightening due to elasticity and are not comfortable to wear. There were also problems. Although the fiber disclosed in Patent Document 4 is lightweight and solves the problems of water absorption and hydrolysis, there is still room for improvement in dimensional change in a heated state such as hot water, and is disclosed in Patent Document 5. Although the existing fibers are lightweight and have solved the problems of water absorption and hydrolysis, there is still room for improvement in stretchability.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a polyolefin filament which has a small dimensional change while maintaining a low specific gravity and a low water absorption and which has an excellent balance of stress relaxation property.

That is, the gist of the present invention is as follows.
[1] A core layer (Y) made of a resin composition containing 4-methyl-1-pentene/α-olefin copolymer (A) satisfying the following requirements (a) to (c):
Consists of ethylene-based polymer, propylene-based polymer, butene-based polymer and 4-methyl-1-pentene-based polymer (excluding 4-methyl-1-pentene/α-olefin copolymer (A)) A polyolefin multilayer filament comprising a surface layer (Z) comprising at least one thermoplastic resin selected from the group:
A polyolefin multi-layer filament, wherein the filament has an absolute value of dry heat dimensional change rate of 10% or less measured according to JIS L1013.
Requirement (a) ; The copolymer (A) is derived from the structural unit (i) derived from 4-methyl-1-pentene and α-olefin (excluding 4-methyl-1-pentene). It is composed of 60 to 90 mol% of the structural unit (i) and 10 to 40 mol% of the structural unit (ii) with the total of the structural unit (ii) being 100 mol %.
Requirement (b) : The intrinsic viscosity [η] measured in decalin at 135°C is in the range of 0.5 to 5.0 dL/g.
Requirement (c) ; density (measured by ASTM D1505) is in the range of 870 to 830 kg/m ³ .
[2] The polyolefin multilayer filament according to the above [1], which has a peeling force of 10 N/10 mm or less after heat treatment of the polyolefin multilayer filament at 50° C. for 3 days.
[3] The polyolefin multilayer filament according to the above [1] or [2], wherein the 4-methyl-1-pentene/α-olefin copolymer (A) satisfies the following requirement (d).
Requirement (d) ; the tan δ peak temperature obtained by performing dynamic viscoelasticity measurement at a frequency of 10 rad/s (1.6 Hz) in the temperature range of −40 to 150° C. is 0° C. or higher and 40° C. or lower [4 ] A spun yarn containing the polyolefin multilayer filament according to any one of [1] to [3] above.
[5] A fibrous structure containing the polyolefin multilayer filament according to any one of [1] to [4] above.

The polyolefin multilayer filament of the present invention has high tensile elongation and stress relaxation property, but exhibits low dimensional change property and low tack property.

Hereinafter, the polyolefin multilayer filament of the present invention will be described.
The polyolefin multilayer filament of the present invention comprises a core layer (Y) made of a resin composition (X) containing a specific 4-methyl-1-pentene/α-olefin copolymer (A), an ethylene polymer, A polyolefin multi-layer filament comprising a surface layer (Z) made of at least one thermoplastic resin selected from the group consisting of a propylene polymer, a butene polymer and a 4-methyl-1-pentene polymer. In the following description, the core layer may be referred to as the core layer and the surface layer may be referred to as the sheath layer.

Hereinafter, the 4-methyl-1-pentene/α-olefin copolymer (A) constituting the core layer (Y) of the polyolefin multilayer filament of the present invention will be described.
<4-Methyl-1-pentene/α-olefin copolymer (A)>
The 4-methyl-1-pentene/α-olefin copolymer (A) (hereinafter, also simply referred to as “copolymer (A)”) satisfies all the following requirements (a) to (d).

Requirement (a) ; the copolymer (A) is derived from a structural unit (i) derived from 4-methyl-1-pentene and α-olefin (excluding 4-methyl-1-pentene). It is composed of 60 to 90 mol% of the structural unit (i) and 10 to 40 mol% of the structural unit (ii) with the total of the structural unit (ii) being 100 mol %.

That is, the lower limit of the proportion of the structural unit (i) is 60 mol %, preferably 65 mol %, and more preferably 68 mol %. On the other hand, the upper limit of the proportion of the structural unit (i) is 90 mol%, preferably 87 mol%, more preferably 85 mol%, and particularly preferably 80 mol%. As described above, in the present invention, when the ratio of the structural unit (i) in the copolymer (A) is not less than the lower limit value, the peak value temperature of tan δ is near room temperature, and thus the shape following property is improved. And the stress relaxation property is excellent, and when the ratio of the structural unit (i) is not more than the upper limit value, the resin has appropriate flexibility.

The upper limit of the proportion of the structural unit (ii) is 40 mol %, preferably 35 mol %, more preferably 32 mol %. On the other hand, the lower limit of the proportion of the structural unit (ii) is 10 mol %, preferably 13 mol %, more preferably 15 mol %, and particularly preferably 20 mol %.

Examples of the α-olefin leading to the structural unit (ii) include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1- C2-C20, such as tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, etc., preferably a C2-C15, more preferably a C2-C10 linear α-olefin, 3 -Methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4,4-dimethyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene , 4-ethyl-1-hexene, 3-ethyl-1-hexene and the like, and branched α-olefins having 5 to 20 carbon atoms, preferably 5 to 15 carbon atoms. Among these, ethylene, propylene, 1-butene, 1-pentene, 1-hexene and 1-octene are preferable, and ethylene and propylene are particularly preferable.

Here, in one embodiment of the present invention, the copolymer (A) usually consists of the structural unit (i) and the structural unit (ii). However, if the copolymer (A) is in a small amount (for example, 10 mol% or less) that does not impair the object of the present invention, the structural unit (i) and the structural unit (ii) as well as the structural unit ( As iii), a constitutional unit derived from 4-methyl-1-pentene and another monomer other than the α-olefin leading to the constitutional unit (ii) may be further contained. Specific preferred examples of such other monomers include 5-vinyl-2-norbornene and 5-ethylidene when the copolymer (A) is a 4-methyl-1-pentene/propylene copolymer. -2-norbornene etc. are mentioned.

Requirement (b) ;
The intrinsic viscosity [η] measured at 135°C in decalin is usually 0.5 to 5.0 dL/g, preferably 0.5 to 4.0 dL/g, and more preferably 0.5 to 3.5 dL/g. It is a range.

As will be described later, by using hydrogen together during the polymerization, the molecular weight can be controlled, and it is possible to freely obtain low molecular weight to high molecular weight and adjust the intrinsic viscosity [η]. When the intrinsic viscosity [η] is less than 0.5 dL/g or more than 5.0 dL/g, the moldability may be impaired when the polymer composition is processed into a sheet or the like. is there.

Requirement (c) ;
The density (measured by ASTM D1505) is usually 870 to 830 kg/m ³ , preferably 865 to 830 kg/m ³ , and more preferably 855 to 830 kg/m ³ . The details of the measurement conditions and the like are as described in the section of Examples described later.

The density can be appropriately changed depending on the comonomer composition ratio of the copolymer (A), and the copolymer (A) having a density within the above range is advantageous in producing a lightweight sheet.

A particularly preferred form of the 4-methyl-1-pentene/α-olefin copolymer (A) further satisfies the following requirement (d) in addition to the requirements (a), (b) and (c), In a preferred embodiment, in addition to the requirements (a) to (d), one or more, preferably 2 or more selected from the requirements (e), (f), (g), (h) and (i), It is more preferably 3 or more, particularly preferably all.

Requirement (d) ;
The melting point (Tm) measured by DSC is below 110° C. or not observed. More preferably below 100° C. or not observed. More preferably below 85° C. or not observed. Particularly preferably, the melting point (Tm) is not observed. The melting point (Tm) of the copolymer (A-1) can be arbitrarily controlled by the comonomer species and the comonomer composition, and when the melting point (Tm) satisfies the above requirements, the polyolefin multilayer filament of the present invention is excellent. Shows flexibility and toughness.

Requirement (e) ;
The ratio between the weight average molecular weight (Mw) and the number average molecular weight (Mn) (molecular weight distribution; Mw/Mn) measured by gel permeation chromatography (GPC) is usually 1.0 to 3.5, preferably 1 .2 to 3.0, more preferably 1.5 to 2.8. The details of the measurement conditions and the like are as described in the section of Examples described later. If the Mw/Mn is more than 3.5, there is concern about the influence of the low molecular weight and low stereoregular polymer derived from the composition distribution, resulting in poor moldability.
Here, in the present invention, if the catalyst described below is used, a copolymer (A) satisfying the above requirement (c) can be obtained within the range of the intrinsic viscosity [η] indicated by the above requirement (b). it can. The values of Mw/Mn and the following Mw are values measured by the method adopted in Examples described later.

The weight average molecular weight (Mw) of the copolymer (A) measured by gel permeation chromatography (GPC) is preferably 500 to 10,000,000, more preferably 1,000 in terms of polystyrene. ˜5,000,000, more preferably 1,000 to 2,500,000.

Requirement (f);
It is preferable that the tan δ peak value obtained by performing dynamic viscoelasticity measurement at a frequency of 10 rad/s (1.6 Hz) in the temperature range of −40 to 150° C. is 1.0 or more and 5.0 or less. , 1.5 or more and 5.0 or less, more preferably 2.0 or more and 4.0 or less.

Requirement (g) ;
From the viewpoint of further increasing the stress absorbability at room temperature of the polyolefin multilayer filament of the present invention, it was obtained by performing dynamic viscoelasticity measurement at a frequency of 10 rad/s (1.6 Hz) in the temperature range of -40 to 150°C. The tan δ peak temperature of the copolymer (A) is preferably 0°C or higher and 40°C or lower, more preferably 10°C or higher and 40°C or lower, and further preferably 20°C or higher and 40°C or lower. It is more preferably 25° C. or higher and 40° C. or lower.

By setting the tan δ peak temperature of the copolymer (A) within the above temperature range, the value of tan δ at room temperature can be further increased. Further, by having a tan δ peak value at room temperature, it is possible to change the vibration absorbing property, the hardness of the material and the followability according to the rate of tension or deformation.

Requirement (h) ;
From the viewpoint of further increasing the flexibility of the polyolefin multilayer filament of the present invention, the copolymer (A after 15 seconds from the start of pressing needle contact, measured according to JIS K6253, in the state of a press sheet having a thickness of 3 mm. The Shore A hardness of) is preferably 5 or more and 95 or less, more preferably 10 or more and 95 or less, still more preferably 25 or more and 90 or less, and particularly preferably 50 or more and 90 or less.

From the viewpoint of further enhancing the stress relaxation property and the shape following property of the polyolefin multilayer filament of the present invention, according to JIS K6253, the pressing of the copolymer (A) measured in the state of a press sheet having a thickness of 3 mm is performed. The amount of change ΔHS between the value of Shore A hardness immediately after the start of needle contact and the value of Shore A hardness 15 seconds after the start of pressing needle contact is preferably 10 or more and 60 or less, and 10 or more and 50 or less. More preferably, it is more preferably 15 or more and 45 or less.
The above ΔHS is a value calculated according to the following formula.
ΔHS=(Shore immediately after the start of contact with the needle)-(A hardness value-Shear A hardness value 15 seconds after the start of contact with the needle)

Requirement (h);
From the viewpoint of reducing the width of the composition distribution to reduce the amount of low molecular weight components and making it less likely to cause poor molding due to stickiness caused by low molecular weight components, the extraction amount of the copolymer (A) with methyl acetate is 0. The content is preferably not less than mass% and not more than 1.5 mass%, more preferably not less than 0 mass% and not more than 1.0 mass%, further preferably not less than 0 mass% and not more than 0.8 mass%, and 0 It is more preferable that the content is not less than mass% and not more than 0.7 mass %.

The amount of extraction into methyl acetate should be measured, for example, as the mass change amount of the copolymer (A) before and after extraction when the components contained in the copolymer (A) are extracted into methyl acetate by the Soxhlet extraction method. You can

<Method for producing 4-methyl-1-pentene/α-olefin copolymer (A)>
The method for producing the copolymer (A) is not particularly limited, but the copolymer (A) may be, for example, 4-methyl-1-pentene and the above-mentioned “α-olefin leading to the structural unit (ii)”. Can be obtained by polymerizing in the presence of a suitable polymerization catalyst.

Here, as the polymerization catalyst that can be used in the present invention, a conventionally known catalyst, for example, a magnesium-supported titanium catalyst, WO 01/53369 pamphlet, WO 01/27124 pamphlet, and JP-A-3-193796. The metallocene catalysts described in International Publication No. 2011/055803, International Publication No. 2014/050817, and the like in the publication or JP-A-02-41303 are preferably used.

<Thermoplastic elastomer (B)>
The resin composition (X) constituting the core layer (Y) of the polyolefin multi-layer filament of the present invention contains the 4-methyl-1-pentene/α-olefin copolymer (A) in an excellent range. The thermoplastic elastomer (B) other than the copolymer (A) may be added. When it is added, the addition amount thereof is generally 50 parts by mass or less, preferably 40 parts by mass or less, per 100 parts by mass of the resin composition (X). In the present invention, the case where the resin composition (X) is composed of the copolymer (A) and the thermoplastic elastomer (B) may be particularly referred to as the resin composition (X1).

When the total amount of the 4-methyl-1-pentene/α-olefin copolymer (A) and the thermoplastic elastomer (B) is 100 parts by mass, in the above composition, from the viewpoint of flexibility and stress relaxation property. The upper limit of the content of the polymer (A) is usually 100 parts by mass, preferably 90 parts by mass, more preferably 75 parts by mass, particularly preferably 60 parts by mass, and the lower limit is usually 10 parts by mass, preferably The amount is 15 parts by mass, more preferably 25 parts by mass, particularly preferably 30 parts by mass.

In other words, the lower limit of the content of the thermoplastic elastomer (B) is usually 0 parts by mass, preferably 10 parts by mass, more preferably 25 parts by mass, particularly preferably 40 parts by mass, and the upper limit is usually 90 parts by mass. Parts, preferably 85 parts by weight, more preferably 75 parts by weight, particularly preferably 70 parts by weight.

The thermoplastic elastomer (B) referred to in the present invention is a polymer that exhibits thermoplastic properties when heated to a temperature equal to or higher than the melting point, while exhibiting rubber elasticity properties at room temperature. Specific examples of such a thermoplastic elastomer (B) include a polyolefin-based elastomer (B-1), a polystyrene-based elastomer (B-2), a polyester-based elastomer (B-3), and a polyamide-based elastomer (B-4). Are listed.

<<Polyolefin Elastomer (B-1)>>
The first aspect of the polyolefin elastomer (B-1) is a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, and a copolymer of ethylene, an α-olefin having 3 to 20 carbon atoms and a cyclic olefin. Copolymer of ethylene, styrene, vinyl acetate, (meth)acrylic acid, (meth)acrylic acid ester and other vinyl compounds as comonomer, and copolymer of propylene and α-olefin having 4 to 20 carbon atoms , A propylene-based copolymer containing various copolymers of propylene, an α-olefin having 4 to 20 carbon atoms and a cyclic olefin, and various vinyl compounds such as styrene, vinyl acetate, (meth)acrylic acid, and (meth)acrylic acid ester as comonomers. Examples thereof include polymers (excluding 4-methyl-1-pentene/α-olefin copolymer (A)).

The form of copolymerization may be either block copolymerization or graft copolymerization. For example, a block copolymer of a polyolefin block that forms a polymer having high crystallinity such as polyethylene or polypropylene that serves as a hard portion and an amorphous α-olefin copolymer that serves as a soft portion can be used.

Specific examples of the first aspect include JSR Corporation under the trade name DYNARON (registered trademark), Mitsui Chemicals under the trade name Tufmer (registered trademark), Notio (registered trademark), and Dow Chemical Company under the trade name. Examples include ENGAGE ^™ , INFUSE ^™ , VERSIFY ^™ , and those commercially available from ExxonMobil Chemical Company under the trade name Vistamaxx ^™ .

The second aspect of the polyolefin-based elastomer (B-1) is one selected from the group consisting of polyethylene and polypropylene, and polybutadiene, hydrogenated polybutadiene, polyisoprene, hydrogenated polyisoprene, polyisobutylene, ethylene-propylene copolymer. , Ethylene/propylene/diene copolymer, ethylene/butene copolymer, hydrogenated styrene butadiene, α-olefin copolymer (however, 4-methyl-1-pentene/α-olefin copolymer (A) Except for 1) selected from the group consisting of At this time, the ethylene/propylene copolymer, the ethylene/propylene/diene copolymer, and the ethylene/butene copolymer may be partially or completely crosslinked.
Specific examples of the second embodiment include trade names Mirastomer (registered trademark) manufactured by Mitsui Chemicals, Esporex (registered trademark) manufactured by Sumitomo Chemical, and Thermoran (registered trademark), Zelas (registered trademark) manufactured by Mitsubishi Chemical. Trademark), trade name Santoprene (registered trademark)” from ExxonMobil Chemical Company, and the like.

The polyolefin-based elastomer according to the present invention is at least one selected from the group consisting of acid anhydride groups, carboxyl groups, amino groups, imino groups, alkoxysilyl groups, silanol groups, silyl ether groups, hydroxyl groups and epoxy groups. It may be modified with a functional group of.

<<Styrene elastomer (B-2)>>
As the styrene elastomer (B-2), a block copolymer (SBS) of a polystyrene block that is a hard part (crystal part) and a diene monomer block that is a soft part, a hydrogenated styrene/butadiene/styrene block copolymer Polymer (HSBR), styrene/ethylene/propylene/styrene block copolymer (SEPS), styrene/ethylene/butene/styrene block copolymer (SEBS), styrene/isoprene/styrene block copolymer (SIS), styrene Examples thereof include isobutylene/styrene copolymer (SIBS) and styrene/isobutylene copolymer (SIB). The styrene elastomer is used alone or in combination of two or more kinds.

Specific examples of the hydrogenated styrene/butadiene/styrene block copolymer include those commercially available from JSR Corporation under the trade name of Dynaron (registered trademark).

The styrene/ethylene/propylene/styrene block copolymer is obtained by hydrogenating a styrene/isoprene/styrene block copolymer (SIS). Specific examples of SIS include JSR Corporation under the trade name: JSR SIS (registered trademark), Kuraray Co., Ltd. under the trade name: Hybler (registered trademark), or Shell Co. under the trade name: Kraton D (registered trademark). Examples include commercially available products.

Further, specific examples of SEPS include those marketed by Kuraray Co., Ltd. under the trade name: Septon (registered trademark) or Shell Co., Ltd. under the trade name: Kraton (registered trademark).

Specific examples of SEBS include those marketed by Asahi Kasei Co., Ltd. under the trade name: Tuftec (registered trademark) or Shell Co., Ltd. under the trade name: Kraton (registered trademark).

Specific examples of SIB and SIBS include those marketed by Kaneka Co., Ltd. under the trade name of SIVSTAR (registered trademark).

≪Polyester elastomer (B-3)≫
Examples of the polyester elastomer according to the present invention include a block copolymer of an aromatic polyester and an aliphatic polyester, and a block copolymer of an aromatic polyester and an aliphatic polyether. It is preferably a block copolymer with a group polyether.

The aromatic polyester in the polyester elastomer is preferably a polybutylene terephthalate resin and/or a polyethylene terephthalate resin. Here, the polybutylene terephthalate-based resin means a polyester using terephthalic acid or a combination of terephthalic acid and isophthalic acid as a dicarboxylic acid component and 1,4-butanediol as a diol component. , A part of the dicarboxylic acid component (less than 50 mol%) is replaced with another dicarboxylic acid component or an oxycarboxylic acid component, and a part of the diol component (less than 50 mol%) is a low molecular diol component other than the butanediol component. The polyester may be replaced with. The polyethylene terephthalate-based resin means a polyester using terephthalic acid as a dicarboxylic acid component, or a dicarboxylic acid component obtained by combining terephthalic acid and isophthalic acid, and ethylene glycol as a diol component. Part of the component (less than 50 mol%) was replaced with another dicarboxylic acid component or oxycarboxylic acid component, or part of the diol component (less than 50 mol%) was replaced with a low molecular diol component other than the ethylene glycol component. It may be polyester.

Moreover, the aliphatic polyether in the polyester elastomer is preferably a polyalkylene glycol resin, and more preferably a polytetramethylene glycol resin and/or a polyethylene glycol resin. Here, the polyalkylene glycol-based resin means an aliphatic polyether containing polyalkylene glycol as a main component, but a part (less than 50% by mass) of the polyether portion is dioxygen other than the alkylene glycol component. It may be an aliphatic polyether substituted with a component. In addition, the polytetramethylene glycol-based resin means a polyalkylene glycol having polytetramethylene glycol as a main component, but a part (less than 50% by mass) of the aliphatic polyether portion is a tetramethylene glycol component. It may be an aliphatic polyether substituted with a dioxy component other than. Furthermore, the polyethylene glycol-based resin means a polyalkylene glycol having polyethylene glycol as a main component, but a part (less than 50% by mass) of the aliphatic polyether portion is a dioxy component other than the ethylene glycol component. It may be a substituted aliphatic polyether. Here, the term "mainly" refers to a case where the total amount of the aliphatic polyether portion is 100% by mass, and occupies 50% by mass or more.

Commercially available polyester-based elastomers include "Hytrel (registered trademark)" manufactured by Toray-Dupont Co., Ltd., "Perprene (registered trademark)" manufactured by Toyobo Co., Ltd. and "Primalloy (registered trademark)" manufactured by Mitsubishi Chemical Corporation. Trademark)” and the like.

≪Polyamide elastomer (B-4)≫
The polyamide elastomer (B-4) according to the present invention is a polyamide resin such as an aliphatic polyamide (nylon 6, nylon 11, nylon 12, nylon 66, nylon 610, nylon 612) or the like, as well as a polyamide and an aliphatic polyester. Examples thereof include block copolymers and block copolymers of polyamide and aliphatic polyether.

Commercially available polyamide-based elastomers include "UBESTA (registered trademark)" manufactured by Ube Industries, "Daiamide (registered trademark)", "Vestamide E (registered trademark)" manufactured by Daicel-Evonik, and Arkema. "Pebax (registered trademark)" and the like.

<Other polymers>
The resin composition (X) constituting the polyolefin multilayer filament of the present invention has a conventionally known low density other than the copolymer (A) and the thermoplastic elastomer (B) within a range not impairing the effects of the present invention. , Medium density, high density polyethylene, high pressure low density polyethylene, isotactic polypropylene, syndiotactic polypropylene, poly 1-butene, poly 4-methyl-1-pentene, poly 3-methyl-1-butene, cyclic olefin It may contain a resin represented by a polymer, a chlorinated polyolefin, a thermoplastic polyurethane or the like, and an additive described later.

<Additive>
The poly-4-methyl-1-pentene/α-olefin copolymer (A) in the present invention may be one which has been subjected to various modifications by adding a secondary additive. Specific examples of secondary additives include plasticizers, ultraviolet absorbers, infrared absorbers, optical brighteners, release agents, antibacterial agents, nucleating agents, heat stabilizers, antioxidants, slip agents, antistatic agents. Examples include, but are not limited to, agents, anti-coloring agents, regulators, matting agents, defoamers, preservatives, gelling agents, latices, fillers, inks, colorants, dyes, pigments, and fragrances. These secondary additives may be used alone or in combination of two or more.

Examples of the plasticizer include aromatic carboxylic acid esters (dibutyl phthalate, etc.), aliphatic carboxylic acid esters (methyl acetylricinoleate, etc.), aliphatic dialbonic acid esters (adipic acid-propylene glycol-based polyester, etc.), aliphatic tricarboxylic acids. Examples thereof include esters (triethyl citrate and the like), phosphate triesters (triphenyl phosphate and the like), epoxy fatty acid esters (epoxy butyl stearate and the like), petroleum resins and the like.

As the release agent, lower (C _1-4 ) alcohol ester of higher fatty acid (butyl stearate, etc.), polyhydric alcohol ester of fatty acid (C _4-30 ) (hardened castor oil, etc.), glycol ester of fatty acid, fluid Paraffin and the like can be mentioned.

As antioxidants, phenol-based (2,6-di-t-butyl-4-methylphenol etc.), polycyclic phenol-based (2,2′-methylenebis(4-methyl-6-t-butylphenol) etc.) , Phosphorus-based (tetrakis(2,4-di-t-butylphenyl)-4,4-biphenylenediphosphonate, etc.), amine-based (N,N-diisopropyl-p-phenylenediamine, etc.) antioxidants Can be mentioned.

Examples of the ultraviolet absorber include benzotriazole type, benzophenone type, salicylic acid type, and acrylate type.

Examples of the antibacterial agent include quaternary ammonium salts, pyridine compounds, organic acids, organic acid esters, halogenated phenols and organic iodine.

Examples of the surfactant include nonionic, anionic, cationic or amphoteric surfactants. Nonionic surfactants include polyethylene glycol type nonionic surfactants such as higher alcohol ethylene oxide adducts, fatty acid ethylene oxide adducts, higher alkylamine ethylene oxide adducts, polypropylene glycol ethylene oxide adducts, polyethylene oxide, fatty acid esters of glycerin. , Fatty acid ester of pentaerythritol, fatty acid ester of sorbit or sorbitan, alkyl ether of polyhydric alcohol, polyhydric alcohol type nonionic surfactant such as aliphatic amide of alkanolamine, and the like, and anionic surfactant Are, for example, sulfate ester salts such as alkali metal salts of higher fatty acids, sulfonate salts such as alkylbenzene sulfonates, alkyl sulfonates, paraffin sulfonates and phosphate ester salts such as higher alcohol phosphate ester salts. Examples of the cationic surfactant include quaternary ammonium salts such as alkyl trimethyl ammonium salts. Examples of the amphoteric surfactant include amino acid-type double-sided surfactants such as higher alkylaminopropionate, betaine-type amphoteric surfactants such as higher alkyldimethylbetaine and hydroxyethylbetaine at higher alkyl.

Examples of the antistatic agent include the above-mentioned surfactant, fatty acid ester, and polymer type antistatic agent. Examples of fatty acid esters include esters of stearic acid and oleic acid, and examples of polymeric antistatic agents include polyether ester amides.

Examples of the pigment include an inorganic content (titanium oxide, iron oxide, chromium oxide, cadmium sulfide, etc.) and an organic pigment (azo lake type, thioindigo type, phthalocyanine type, anthraquinone type). Examples of the dye include azo type, anthraquinone type and triphenylmethane type. The addition amount of these pigments and dyes is not particularly limited, but is generally 5 parts by mass or less, and preferably 0.1 to 3 parts by mass, with respect to 100 parts by mass of the copolymer (A).

As a slip agent, wax (carnauba wax, etc.), higher fatty acid (stearic acid, etc.), training fatty acid salt (calcium stearate, etc.), higher alcohol (stearyl alcohol, etc.), higher fatty acid amide (stearic acid amide, erucic acid amide, etc.) Etc.

The addition amount of each of the above-mentioned various additives is not particularly limited depending on the application within a range that does not impair the object of the present invention, but with respect to the 4-methyl-1-pentene/α-olefin polymer (A). It is preferably 0.01 to 30 parts by mass, respectively.

≪Surface layer (Z)≫
The surface layer (Z) of the multi-layer polyolefin multi-layer filament of the present invention comprises a thermoplastic resin (C). As such a thermoplastic elastomer (C), the above-mentioned thermoplastic elastomer (B) can be used as it is without limitation. The thermoplastic elastomer (C) may be the same as or different from the thermoplastic elastomer (B).
Further, the surface layer (Z) in the present invention is a layer at least a part of which is in contact with the core layer (Y).

Here, "at least a part is in contact with the base material layer" means that the surface layer is in contact with a part of the base material layer, or that the surface layer is in contact with the whole base material layer. It means that the contact ratio between the base material layer and the surface layer is preferably 30% to 100%, and more preferably 50% to 100% with respect to the total area of the base material layer.
The ratio of the thickness of the base material layer to the surface layer in the laminate of the present invention [thickness of the base material layer/thickness of the surface layer] is not particularly limited, but is 1 to 100/100/1 to 100. It is preferably 1 to 50/100/1 to 50.

<Thermoplastic polymer (C)>
The thermoplastic polymer (C) is preferably selected from the olefin resin (C-1).

<<Olefin Resin (C-1)>>
Specific examples of the olefin resin (C-1) include a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, a copolymer of ethylene, an α-olefin having 3 to 20 carbon atoms and a cyclic olefin, Ethylene polymers containing various vinyl compounds such as styrene, vinyl acetate, (meth)acrylic acid, and (meth)acrylic acid ester as comonomers, copolymers of propylene and α-olefins having 4 to 20 carbon atoms, and propylene. Propylene-based polymers having various vinyl compounds such as copolymers of α-olefins having 4 to 20 carbon atoms and cyclic olefins, styrene, vinyl acetate, (meth)acrylic acid, and (meth)acrylic acid esters as comonomers, 1 A butene-based polymer represented by a copolymer of butene and an α-olefin having 2 or 3 carbon atoms, a copolymer of 4-methyl-1-pentene and an α-olefin having 2 to 20 carbon atoms, etc. Representative examples thereof include 4-methyl-1-pentene-based polymers (excluding 4-methyl-1-pentene/α-olefin copolymer (A)). More specifically, low density, medium density, high density polyethylene, high pressure method low density polyethylene, isotactic polypropylene, syndiotactic polypropylene, poly 1-butene, poly 4-methyl-1-pentene, poly 3-methyl. Examples include -1-butene, cyclic olefin copolymer, chlorinated polyolefin and the like.

The ethylene polymer may be an ethylene homopolymer (homopolymer) or a copolymer of ethylene and another monomer (copolymer). For example, it may be produced by a conventionally known method. Examples include low-density polyethylene, medium-density polyethylene, high-density polyethylene, and high-pressure low-density polyethylene. Further, examples of the ethylene polymer include ethylene polymer elastomers.

When the ethylene polymer is a copolymer, the copolymer is preferably a copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, and ethylene and α having 3 to 10 carbon atoms. -A copolymer with an olefin is more preferable.

The ratio of the constitutional units derived from ethylene in the ethylene-based polymer is preferably 50 mol% to 100 mol%, and 60 mol% when all the constitutional units in the ethylene-based polymer are 100 mol%. It is more preferably about 99 mol%.

The propylene-based polymer may be a propylene homopolymer (homopolymer) or a copolymer (copolymer) of propylene and another monomer. For example, an isotactic propylene-based polymer, Examples thereof include syndiotactic propylene-based polymers. As a copolymer of propylene and another monomer, a random copolymer of propylene and α-olefin having 2 to 20 carbon atoms (however, excluding propylene), propylene and α having 2 to 20 carbon atoms are used. -A block copolymer of olefins (excluding propylene). Examples of the propylene-based polymer also include propylene-based polymer elastomers.

When the propylene-based polymer is a copolymer, the copolymer is preferably a copolymer of propylene and an α-olefin having 2 to 20 carbon atoms (excluding propylene).

The ratio of the constitutional units derived from propylene in the propylene-based polymer is preferably 50 mol% to 100 mol%, and 60 mol% when all the constitutional units in the propylene-based polymer are 100 mol%. It is more preferably about 99 mol%.

The butene-based polymer may be a homopolymer of butene or a copolymer of butene and another monomer. For example, a homopolymer of 1-butene, 1 Examples thereof include copolymers of butene and olefins other than 1-butene. Examples of the copolymer include 1-butene/ethylene random copolymer, 1-butene/propylene random copolymer, 1-butene/methylpentene copolymer, 1-butene/methylbutene copolymer, 1- Examples thereof include butene/propylene/ethylene copolymers.

When the butene-based polymer is a copolymer, the copolymer is preferably a copolymer of 1-butene and an olefin other than 1-butene.

The ratio of the constitutional unit derived from 1-butene in the butene-based polymer is preferably 50 mol% to 100 mol% when all the constitutional units in the butene-based polymer are 100 mol %, 70 More preferably, it is from mol% to 99 mol %.

As the 4-methyl-1-pentene-based polymer, even if it is a homopolymer of 4-methyl-1-pentene (a homopolymer), a copolymer of 4-methyl-1-pentene and another monomer ( Copolymer), and examples thereof include a homopolymer of 4-methyl-1-pentene, a copolymer of 4-methyl-1-pentene and an olefin other than 4-methyl-1-pentene, and the like. Examples of the copolymer include 4-methyl-1-pentene/ethylene random copolymer, 4-methyl-1-pentene/propylene random copolymer, 4-methyl-1-pentene/1-hexene copolymer. Combined, 4-methyl-1-pentene/1-octene copolymer, 4-methyl-1-pentene/1-decene copolymer, 4-methyl-1-pentene/1-hexadecene copolymer, 4-methyl Examples thereof include -1-pentene/1-octadecene copolymer, 4-methyl-1-pentene/1-hexadecene/1-octadecene copolymer, and the like.

When the 4-methyl-1-pentene polymer is a copolymer, the copolymer is preferably a copolymer with an olefin other than 4-methyl-1-pentene.
When the ratio of the constituent units derived from 4-methyl-1-pentene in the 4-methyl-1-pentene polymer is 100 mol% for all constituent units in the 4-methyl-1-pentene polymer. Further, it is preferably 80 mol% to 100 mol%, and more preferably 90 mol% to 99 mol%.
The preferable ranges of the density, tensile modulus and melting point of the thermoplastic polymer (C) are as described above.

The melt flow rate (MFR) of the thermoplastic polymer (C) is preferably 0.1 g/10 min to 100 g/10 min, and more preferably 0.5 g/10 min to 50 g/from the viewpoint of spinnability and mechanical properties of the filament. More preferably, it is 10 minutes.

The melt flow rate (MFR) of the thermoplastic polymer B is based on ASTM D1238, and the ethylene polymer and the butene polymer are values measured at 190° C. under a load of 2.16 kg, and the propylene type. The polymer has a value measured at 230° C. under a load of 2.16 kg, and the 4-methyl-1-pentene polymer has a value measured at 260° C. under a load of 5.0 kg.

The surface layer (Z) contains, in addition to the thermoplastic polymer (C), a thermoplastic elastomer (D) which is a polymer other than the thermoplastic polymer (C), a known thermoplastic resin, a known additive and the like. You may have. Examples of the thermoplastic elastomer (D) may include the thermoplastic elastomer (B) optionally used for the core layer (Y).

From the viewpoint that the effect of the present invention is more effectively exhibited, the content of the thermoplastic polymer (C) in the surface layer (Z) is 60% by mass or more based on the total mass of the surface layer (Z). 80 mass% or more is more preferable, and 100 mass% (that is, the surface layer (Z) is composed of the thermoplastic polymer (C)) is most preferable.

<Method for producing multi-layer polyolefin filament>
The polyolefin multilayer filament of the present invention can be obtained, for example, by producing a monofilament, a multifilament, a flat yarn, a cut fiber, or a nonwoven fabric by extruding a molten resin composition through a spinneret. At this time, a filament having a core-sheath structure can be produced by using a multi-layered die.

The melting temperature in the melt spinning process for producing the monofilament, the multifilament, and the flat yarn can be appropriately selected according to the melting point of the copolymer (A), but may be in the range of 180 to 280°C. A more preferable range is 180 to 230°C. When the melting temperature is within the above range, excessive thermal decomposition of the copolymer (A) can be suppressed, and the elongational viscosity of the fibrous strand discharged from the die is sufficiently reduced, which is excellent in mechanical strength, A fiber with good spinnability can be obtained.

The fibers thus obtained may be further drawn. If the degree of stretching is such that the copolymer (A) is effectively imparted with at least uniaxial molecular orientation, the elastic modulus and strength can be improved. The draw ratio is usually 1.05 to 10.0 times, preferably 1.1 to 7.0 times, and more preferably 1.2 to 6.0 times.

Stretching in the present invention refers to a step of mechanically stretching the filament at a temperature equal to or lower than the melting point of the material to orient the molecular chains parallel to the tensile direction. By this operation, the tensile strength is remarkably improved and the toughness is increased. After the drawing process, if it is reheated to a temperature higher than the drawing temperature, it will tend to shrink to its original size.Therefore, in order to stabilize the size and strength, heat treatment (heat setting, heat setting) at a temperature slightly lower than the drawing temperature. ) May be done. In the present invention, the strand obtained in the extrusion step is heated to a specific temperature and stretched. Stretching is performed by a speed ratio (stretch ratio) between the inlet-side take-up roll and the outlet-side take-up roll, and the stretch ratio at this time is preferably 1.1 to 15 times. The heating method at the time of stretching may be any of a hot water tank, an oven, a hot roll and the like, and is not particularly limited, but a hot water tank is more preferable for more uniform heating and stretching.

Stretching using a warm water tank can be realized by arranging a water tank having a length and a depth at which the water temperature can be adjusted and a take-up roll before and after the water tank. Stretching using an oven can be realized by arranging an oven with a length of several meters for adjusting the temperature by arranging an electric heater (infrared heater) as a heat source in the take-up direction and before and after the take-up roll. .. Stretching using hot rolls is achieved by placing water pipes, oil pipes, electric heaters, etc. inside and installing multiple heated and temperature-controlled take-up rolls, and adjusting the rotation speed of the rolls. To be done.

As for the temperature condition during stretching, it is preferable that the surface temperature of the filament before stretching is not less than the glass transition temperature (Tg) and not more than 150° C. in any apparatus such as a warm water tank, an oven and a hot roll. If the surface temperature is low, stretch breakage may occur or high-magnification stretch may not be possible. In addition to the method of performing the stretching step in one stage, a method of appropriately combining these to form a two-stage, three-stage to multi-stage configuration, stretching at a small draw ratio in each stage, and increasing the overall draw ratio to a high draw ratio You can also take When performing multi-stage stretching, the stretching ratio is sequentially changed, for example, 1.1 to 10 times in the first stage and 1.5 to 10 times in the second stage to adjust the overall stretching ratio. At the same time, it is preferable that the heating temperature condition is such that the first stage is the lowest in the above temperature range and the temperature is sequentially increased as the number of stages is increased.

The drawn filament can be wound into a tubular paper, plastic, metallic bobbin or cone shape by a winder to obtain a wound filament.
The cross-sectional shape of the filament of the present invention is not particularly limited with respect to the cross-sectional shape of the fiber. From the viewpoint of fiber strength, a perfectly circular circular cross section is preferable, but a non-circular cross section may be used. Specific examples of the non-circular cross section include a multi-lobed shape, a polygonal shape, a flat shape, an oval shape, a C-shape, an H-shape, an S-shape, a T-shape, a W-shape, an X-shape, and a Y-shape. The cross-sectional shape may be hollow.

The polyolefin multilayer filament of the present invention may have crimps. It is preferable to have crimps because, in the case of a spun yarn, the entanglement of the fibers becomes strong, and in addition, a bulky and lightweight texture can be obtained.

The diameter of the polyolefin multilayer filament of the present invention is not particularly limited, but is preferably 3 to 5000 μm, more preferably 10 to 1500 μm, further preferably 10 to 1000 μm, and particularly preferably 10 to 500 μm. .. The polyolefin multilayer filament satisfying the above range has excellent secondary processability.

The volume ratio of the core layer (Y)/surface layer (Z) of the polyolefin multilayer filament of the present invention is preferably 1/99 to 99/1 (vol%/vol%), and more preferably 40/60 to 95/. 5 (vol%/vol%), and more preferably 45/55 to 90/10 vol%/vol%). A multilayer filament satisfying the above range has a high stress relaxation property and becomes a flexible filament. The volume ratio is a value obtained from a transmission electron microscope image described later.

The absolute value of the dry heat dimensional change rate of the polyolefin multi-layer filament of the present invention measured according to JIS L1013 is 10% or less, preferably 5% or less, more preferably 3% or less, and particularly preferably 2% or less. It has the characteristic that there is. Since the dry heat dimensional change rate is small, the polyolefin multilayer filament of the present invention is suitably used for various applications requiring low dimensional change under high temperature environment.

The polyolefin multilayer filaments of the present invention are characterized by low dimensional change and low tackiness after heat treatment at 50° C. for 3 days. That is, 20 polyolefin multi-layer filaments were arranged and bundled, and the ends were taped and used for the measurement. The bundled polyolefin multi-layer filaments are stacked and a load of 2.5 kg is applied, left for 3 days in a dryer at 50° C., then taken out, and returned to room temperature, and then a T-peel is made in a tensile tester at a speed of 200 mm/min. The strength is 10 N/10 mm or less, preferably 5 N/10 mm or less, more preferably 3 N/10 mm or less, and particularly preferably 2 N/10 mm or less. Due to this characteristic, even when a plurality of the multi-layer filaments of the present invention are bundled and stored for a long period of time under a load, the filaments do not stick to each other, resulting in excellent workability.

The polyolefin multilayer filament of the present invention has a 3% extension elastic modulus and a 50% extension elastic modulus measured according to JIS L1013 in the range of 50 to 100%, preferably 60 to 99%, more preferably 70. The range is from ~99%.

Furthermore, the polyolefin multilayer filament of the present invention preferably has a rate of change of 3% extension elastic modulus and 50% extension elastic modulus measured according to JIS L1013 of 50% or less, preferably 30% or less. The polyolefin multi-layer filament in which the elastic modulus of extension and the rate of change of the elastic modulus of elasticity satisfy the above-mentioned range, is excellent in stretchability because it returns without being plastically deformed even when repeatedly stretched.

The tensile elongation of the polyolefin multilayer filament of the present invention measured in accordance with JIS L1013 is not particularly limited and can be appropriately selected depending on the application and required properties, but is in the range of 30 to 500%. , Preferably 50 to 200%, more preferably 50 to 150%. The polyolefin multilayer filament satisfying the above range has an excellent balance between tensile strength and elongation.

When the tensile elongation is 30% or more, the stretchability of the spun yarn and the secondary processed product is good, which is preferable. On the other hand, when the polyolefin filament is an unstretched yarn, if the elongation is 300% or less, the handleability in the stretching is good, and the mechanical properties can be improved by the stretching, which is preferable.

The polyolefin multilayer filament of the present invention has a tensile stress relaxation rate at 10% elongation of 40% or more, preferably 50% or more, more preferably 60% or more. The upper limit of the tensile stress relaxation rate is 100% or less. The polyolefin multi-layer filament satisfying the above range is excellent in stress relaxation at the time of pulling, and tightening etc. when the secondary processed product is worn is reduced.

The polyolefin multilayer filament of the present invention preferably has a specific gravity of 0.91 or less measured according to JIS L1013. The lower limit of the specific gravity is not particularly limited, but is usually 0.82 or more. The polyolefin multilayer filament satisfying the above range is excellent in lightness.

The tensile strength of the polyolefin multilayer filament of the present invention is not particularly limited and can be appropriately selected depending on the application and required characteristics, but is preferably 0.2 to 7.0 cN/dtex. From the viewpoint of mechanical properties, the higher the tensile strength is, the more preferable it is, but 0.2 cN/dtex or more is preferable. When the strength of the polyolefin filament is 0.2 cN/dtex or more, the yarn breakage is small, the process passability is good, and the durability is excellent, which is preferable. The tensile strength is more preferably 0.2 to 5.0 cN/dtex, further preferably 0.4 to 4.0 cN/dtex.

The initial tensile resistance of the polyolefin multilayer filament of the present invention is not particularly limited and may be appropriately selected depending on the application and required properties, but is preferably 0.01 to 5.0 N/dtex. When the initial tensile resistance is 0.01 N/dtex or more, the process passability and the handleability are good, and the mechanical properties are excellent, which is preferable. On the other hand, when the initial tensile resistance is 5.0 N/dtex or less, the flexibility of the spun yarn and the secondary processed body is not impaired, which is preferable. The initial tensile resistance is more preferably 0.05 to 0.80 N/dtex, further preferably 0.05 to 0.6 N/dtex.

<Use of polyolefin multi-layer filament>
The polyolefin multilayer filament of the present invention has the features of high stress relaxation property, stretchability, and slow relaxation. The polyolefin multilayer filament of the present invention is a conventionally known application, such as clothing materials, medical materials, sanitary materials, fishery materials, agricultural and forestry materials, civil engineering and construction materials, shoes materials, sports materials, and leisure materials. It can be used for applications such as industrial materials and industrial materials. For example, clothing materials include underwear, socks, shirts, briefs, trunks, shorts, camisole, spats, bras, tights, innerwear such as belly bands, T-shirts, sweaters, coats, jackets, jumpers, pants, skirts, and hats. , Outerwear such as gloves, training wear, ski wear, swimwear, leotards, sportswear such as supporters, medical materials such as bandages, poultices, and sanitary materials such as diapers, sanitary products, delivery pads, and breast milk. Pads, mask cords, eye patch cords, wound dressings, etc. are used as fishery materials such as laver nets, winding nets, aquaculture nets and aquaculture nets, and as agricultural and forestry materials such as insect repellent nets, windbreak nets, shading nets, weeds Preventive nets, bird-preventing nets, cuuri nets, flower nets, etc. as civil engineering and construction materials, vegetation nets, sandbag nets, etc., as shoe materials, shoe skin materials, shoelaces, sports, leisure materials, etc. Industrial materials such as golf, baseball, tennis, table tennis, volleyball, badminton, soccer, handball, basketball, hockey, ice hockey, water polo, shoe skins, insect nets, etc. To be

The polyolefin multilayer filament having the multilayer filament structure of the present invention can be processed by, for example, a conventionally known knitting machine or loom to obtain a secondary processed product. The secondary processed product has a net shape, a rope shape, a net shape, and a combination thereof, and there is no limitation with respect to its size, shape, and design. When processing with a knitting machine or loom, the types of knitted fabrics include weft knitted fabrics, warp knitted fabrics, circular knitted fabrics, general fabrics, woven mesh, frog mesh, double frog mesh, etc. Examples thereof include nodule nets, Russell nets, rice bran nets, woven nets, and knotless nets such as meteric fiber nets, but are not limited thereto.

The spun yarn of the present invention may be composed only of the polyolefin multi-layer filament having the multi-layer filament structure of the present invention, or may be a mixed yarn with a chemical fiber or a natural fiber. Further, the spun yarn and the spun yarn made of chemical fiber or natural fiber may be twisted together. The chemical fibers or natural fibers used for the mixed spinning or the twisting may be used alone or in combination.

The chemical fiber in the present invention is not particularly limited and can be appropriately selected depending on the application and required characteristics. Specific examples of the chemical fiber include, but are not limited to, polyester fiber, polyamide fiber, polyacrylonitrile fiber, cellulose fiber, and cellulose fiber. Of these, polyester fibers, polyamide fibers, polyacrylonitrile fibers, cellulose fibers and the like are preferable.

Specific examples of polyester fibers include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, and polylactic acid. Specific examples of polyamide fibers include nylon 6, nylon 66, nylon 610, and the like, specific examples of polyacrylonitrile fibers. , Acrylonitrile-methyl acrylate copolymer, acrylonitrile-ethyl methacrylate copolymer, specific examples of cellulose fiber, cellulose diacetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, specific examples of cellulose fiber Examples thereof include, but are not limited to, viscose rayon and cupra rayon.
The natural fiber in the present invention is not particularly limited and can be appropriately selected depending on the application and required characteristics. Specific examples of natural fibers include, but are not limited to, cotton, silk, linen, and wool.

The secondary processed product of the polyolefin multilayer filament having the multilayer filament structure of the present invention includes clothing materials, sanitary materials, fishery materials, agricultural and forestry materials, civil engineering and construction materials, shoes materials, sports materials, leisure materials. It can be used for applications such as industrial materials and industrial materials. For example, clothing materials include underwear, socks, shirts, briefs, trunks, shorts, camisole, spats, bras, tights, innerwear such as belly bands, T-shirts, sweaters, coats, jackets, jumpers, pants, skirts, and hats. , Outerwear such as gloves, training wear, ski wear, swimwear, sportswear such as leotards and supporters, hygiene materials such as diapers, sanitary products, nursing pads, breast pads, mask strings, eye patch, wound dressing, etc. , Materials for fishing include laver nets, winding nets, aquaculture nets and aquaculture nets, and materials for agriculture and forestry include insect nets, windbreak nets, light-shielding nets, weed prevention nets, bird nets, cucumber nets, Materials for civil engineering and construction such as flower nets, vegetation nets, sandbag nets, etc., materials for shoes such as shoe skin materials, shoelaces, sports, leisure materials such as golf, baseball, tennis, table tennis, volleyball, badminton. As a industrial material such as sports nets for soccer, handball, basketball, hockey, ice hockey, water polo, shoe skins, insect nets, etc., filament materials for three-dimensional modeling (3D printer) used in the hot melt lamination method , Cords, toys, straps for mobile phones, and the like.

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.
Various physical properties in Examples and Comparative Examples were measured by the following methods.

〔composition〕
The content (mol%) of each structural unit (4-methyl-1-pentene and α-olefin) in the 4-methyl-1-pentene copolymer (A) was measured by ¹³ C-NMR.
・Measuring device: Nuclear magnetic resonance device (ECP500 type, manufactured by JEOL Ltd.)
・Observation nucleus: ¹³ C (125 MHz)
・Sequence: Single pulse proton decoupling ・Pulse width: 4.7 μsec (45° pulse)
-Repetition time: 5.5 seconds-Number of integrations: 10,000 times or more-Solvent: Orthodichlorobenzene/deuterated benzene (volume ratio: 80/20) mixed solvent-Sample concentration: 55 mg/0.6 mL
・Measurement temperature: 120℃
・Chemical shift reference value: 27.50 ppm

[Intrinsic viscosity [η]]
The intrinsic viscosity [η] of the copolymer (A) was measured at 135° C. in a decalin solvent using an Ubbelohde viscometer as a measuring device.
After dissolving about 20 mg of copolymer (A) in 25 ml of decalin, the specific viscosity η _sp is measured using an Ubbelohde viscometer in an oil bath at 135°C. After adding 5 ml of decalin to this decalin solution to dilute it, the specific viscosity η _sp is measured in the same manner as above. This dilution operation is repeated twice more, and the value of η _sp /C when the concentration (C) is extrapolated to 0 is determined as the intrinsic viscosity [η] (unit: dl/g) (see the following formula 1).
[Η]=lim(η _sp /C) (C→0)...Equation 1

[Weight average molecular weight (Mw) and molecular weight distribution (Mw/Mn)]
The weight average molecular weight (Mw) of the copolymer (A) and the molecular weight distribution (Mw/Mn) represented by the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) are determined by gel permeation chromatography ( It was calculated by a standard polystyrene conversion method using GPC: Gel Permeation Chromatography).
-Condition-
Measurement device: GPC (ALC/GPC 150-C plus type, suggestive refractometer detector integrated type, manufactured by Waters)
-Column: Two GMH6-HT (manufactured by Tosoh Corporation) and two GMH6-HTL (manufactured by Tosoh Corporation) are connected in series-Eluent: o-dichlorobenzene-Column temperature: 140°C
・Flow rate: 1.0 mL/min

[Melt flow rate (MFR)]
The melt flow rate (MFR: Melt Flow Rate) of the copolymer (A) and polypropylene (PP) was measured at 230° C. under a load of 2.16 kg according to ASTM D1238. The unit is g/10 min.

〔density〕
The density of the copolymer (A) was measured according to JIS K7112 (density gradient tube method). This density (kg/m ³ ) was used as an index of lightness.

[Melting point (Tm)]
The melting point (Tm) of the copolymer (A) was measured using a differential scanning calorimeter (DSC220C type, manufactured by Seiko Instruments Inc.) as a measuring device. About 5 mg of polymer is sealed in a measuring aluminum pan and heated from room temperature to 200° C. at 10° C./min. To completely melt the polymer, hold at 200°C for 5 minutes, then cool at 10°C/min to -50°C. After standing at -50°C for 5 minutes, the second heating is performed at 10°C/min up to 200°C, and the peak temperature (°C) in this second heating is taken as the melting point (Tm) of the polymer. When a plurality of peaks are detected, the peak detected on the highest temperature side is adopted.

[Apparent fineness (dtex)]
It was measured by the B method according to JIS L1013 (2010).

[Core layer (X)/surface layer (Y) ratio (vol%/vol%)]
Using a transmission electron microscope (TEM) H-7650 (manufactured by Hitachi High-Tech Co., Ltd.), the obtained filament was embedded in a resin, trimmed, stained with ruthenium tetroxide (RuO ₄ ), and then an ultrathin section was prepared. I observed. From the observed image, the cross-sectional areas of the core layer (X) and the surface layer (Y) were calculated and the area ratio was calculated.

[Tensile strength (cN/dtex), tensile elongation (%)]
According to JIS L1013 (2010), using a constant speed extension type tensile tester (Autograph AG-500C manufactured by Shimadzu Corporation), each condition of 20°C, relative humidity 65%, and 20°C, relative humidity 95%. It was measured at a gripping distance of 100 mm under a speed of 100 mm/min until the filament broke.
Further, the ratio of the tensile strength at 20° C. and the relative humidity at 95% relative humidity at the tensile strength at 20° C. and 65% relative humidity was calculated as the dry-wet strength ratio (%).

[Initial tensile resistance (N/dtex)]
According to JIS L1013 (2010), the tensile strength and the tensile elongation were measured under the conditions of 20° C. and relative humidity of 65% by the same measurement method. Draw a stress-elongation curve, find the maximum value of load change (maximum tangent angle) with respect to load change that stretches near the origin from this figure, and calculate the initial tensile resistance (N/tex). The apparent Young's modulus was calculated by the formula.
_Tri =P/(l'/l)×F
_Tri : Initial tensile resistance (N/tex)
P: Load (N) at maximum tangent angle
F0: Positive amount fineness (tex)
l: test length (mm)
l': In the load-elongation curve, the length (mm) between the vertical line between the load and the horizontal axis at the maximum tangent angle, and the intersection of the tangent line and the horizontal axis.

[Apparent Young's modulus (N/mm ² )]
According to JIS L1013 (2010), the tensile strength and the tensile elongation were measured under the conditions of 20° C. and relative humidity of 65% by the same measurement method. Draw a stress-elongation curve, find the maximum value of load change (maximum point of contact angle) with respect to load change that changes elongation near the origin from this figure, and calculate the initial tensile resistance (N/tex). The apparent Young's modulus was calculated by the formula.
YM=1000×ρ×T _ri
YM: Apparent Young's modulus (N/mm ² )
ρ: Filament density (g/cm ³ )
_Tri : Initial tensile resistance (N/tex)

[Elastic modulus (%)]
In accordance with JIS L1013 (2010), a filament was stretched by 50% at a gripping interval of 100 mm at a speed of 100 mm/min using a constant-speed extension type tensile tester (Autograph AG-500C manufactured by Shimadzu Corporation). Immediately thereafter, the load was removed at the same speed, the material was held for 2 minutes, and then stretched again to 50% at the same speed. The residual elongation was measured from the stress-elongation curve, and the elongation elastic modulus was calculated by the following formula.
E=(L ₀ −L)/L ₀ ×100
E: Elongation elastic modulus (%)
L ₀ : Elongation at 50% elongation (mm)
L: Residual elongation (mm)

[Dry heat dimensional change rate (%)]
According to JIS L1013 (2010), it was calculated as the B method (filament dimensional change rate). The initial load is applied to the sample to measure 500 mm and two points are hit, and the initial load is taken and suspended in a dryer at 40° C., left for 30 minutes, taken out, cooled to room temperature, and again applied with the initial load. The length between points was measured, and the dry heat dimensional change rate (%) was calculated by the following formula. In addition, |ΔL| was defined as the absolute value of the dry heat dimensional change rate.
ΔL=((L-500)/500)×100
ΔL: Dry heat dimensional change rate (%)
L: Length between two points (mm)

[Hot water dimensional change rate (%)]
According to JIS L1013 (2010), it was calculated as the B method (filament dimensional change rate). The initial load is applied to the sample and 500 mm is measured to hit two points, the initial load is taken, this is left in hot water of 100° C. for 10 minutes, then taken out, cooled to room temperature, and the initial load is applied again, and between two points. The length was measured, and the hot water dimensional change rate (%) was calculated by the following formula. In addition, |ΔL| was the absolute value of the dimensional change rate of hot water.
ΔL=((L-500)/500)×100
ΔL: Hot water dimensional change rate (%)
L: Length between two points (mm)

〔Moisture percentage(%)〕
According to JIS L1013 (2010), measurement was performed under the conditions of humidity 20° C., relative humidity 65%, and 20° C. relative humidity 95%.

[Tensile stress relaxation rate (%)]
Using a constant speed extension type tensile tester (Autograph AG-500C manufactured by Shimadzu Corp.), the filament was stretched 10% at a gripping interval of 100 mm at a speed of 100 mm/min. The stress at that time (initial stress) was measured, the filament was held as it was for 120 seconds, and the change in stress during that time was also measured. Then, the stress relaxation rate was calculated from the difference between the initial stress and the stress 60 seconds after the elongation.
SR=(F ₀ −F)/F ₀ ×100
SR: Tensile stress relaxation rate (%)
F ₀ : Initial stress at 10% elongation (MPa)
F: Stress (MPa) after 120 seconds after 10% elongation

[Peel strength (N/10 mm)]
Twenty polyolefin multi-layer filaments were arranged side by side and bundled, and the ends were taped and used for the measurement. The bundled polyolefin multi-layer filaments are stacked and a load of 2.5 kg is applied, left for 3 days in a dryer at 50° C., then taken out, and returned to room temperature, and then a T-peel is made using a tensile tester at a speed of 200 mm/min The strength was measured.

[Static friction force (N)]
Twenty polyolefin multifilament filaments for which the peeling strength was measured were arranged side by side and taped at the ends for use in the measurement. The bundled polyolefin multilayer filaments and the SUS304 plate were put together, a load of 200 g was applied, and the static frictional force when pulled at a speed of 200 mm/min was measured.

[Example 1]
<Synthesis of 4-methyl-1-pentene/α-olefin copolymer (A-1)>
To a SUS autoclave with a 1.5 L capacity stirring blade that had been sufficiently replaced with nitrogen, 300 ml of n-hexane (dried on activated alumina under a dry nitrogen atmosphere) and 450 ml of 4-methyl-1-pentene were added. After charging at 23° C., 0.75 ml of a 1.0 mmol/ml toluene solution of triisobutylaluminum (TIBAL) was charged and the stirrer was turned.

Next, the autoclave was heated until the internal temperature reached 60° C., and pressurized with propylene so that the total pressure (gauge pressure) was 0.19 MPa.

Then, 1 mmol of methylaluminoxane and 0.01 mmol of diphenylmethylene (1-ethyl-3-t-butyl-cyclopentadienyl) (2,7-di-t- 0.34 ml of a toluene solution containing butyl-fluorenyl)zirconium dichloride was pressed into the autoclave with nitrogen to start the polymerization reaction. During the polymerization reaction, the temperature inside the autoclave was adjusted to 60°C.

After 60 minutes from the start of the polymerization, 5 ml of methanol was pressured into the autoclave with nitrogen to stop the polymerization reaction, and then the pressure inside the autoclave was reduced to atmospheric pressure. After depressurization, acetone was added to the reaction solution while stirring the reaction solution to obtain a polymerization reaction product containing a solvent. Then, the obtained polymerization reaction product containing the solvent was dried under reduced pressure at 130° C. for 12 hours to obtain 44.0 g of powdery 4-methyl-1-pentene copolymer (A-1).
The content rate of 4-methyl-1-pentene in the copolymer (A-1) was 72.5 mol%, and the content rate of propylene was 27.5 mol%. The density of the copolymer (A-1) was 839 kg/m ³ . The intrinsic viscosity [η] of the copolymer A-1 is 1.5 dl/g, the weight average molecular weight (Mw) is 337,000, the molecular weight distribution (Mw/Mn) is 2.1, and the melt flow rate is 2.1. The rate (MFR) was 11 g/10 min. No melting point (Tm) of the copolymer (A-1) was observed.

<Filament spinning>
Using a spinning nozzle with a diameter of 1.4 mmφ x 18 holes and a spinneret capable of forming a core-sheath structure of the core layer/surface layer, and using a spinning equipment (manufactured by Fujibow Ehime Co., Ltd.) having multiple single-screw extruders with a diameter of 40 mmφ. The filament was spun. The composition ratio of the multi-layer filament is adjusted by adjusting the discharge amount of the core layer/surface layer by the number of rotations of the two gear pumps, and the core layer is melted at an appropriate cylinder temperature (230 to 290° C.). 4-Methyl-1-pentene/α-olefin copolymer (A-1) and isotactic polypropylene (C-1) as a resin for the surface layer (produced by Prime Polymer Co., Ltd., trade name Prime Polypro (registered trademark) ) F107, melting point: 162° C., MFR: 7 g/10 min), the strand discharged from the spinning nozzle is guided to an air-cooling type cooling tower to be cooled and solidified, and the drawn filament is wound according to the speed ratio of the heating roll. It was wound on a paper tube by a machine. Table 1 shows the results of measuring the physical properties of the obtained filaments.

[Example 2]
100 parts by mass of 4-methyl-1-pentene/α-olefin copolymer (A-1) was used as the resin composition of the core layer, and the stretching ratio and the core layer/surface layer ratio were adjusted as shown in Table 1. Was spun in the same manner as in Example 1 to obtain a filament. Table 1 shows the evaluation results of physical properties of the obtained filaments.

[Example 3]
100 parts by mass of 4-methyl-1-pentene/α-olefin copolymer (A-1) was used as the resin composition of the core layer, and the stretching ratio and the core layer/surface layer ratio were adjusted as shown in Table 1. Was spun in the same manner as in Example 1 to obtain a filament. Table 1 shows the evaluation results of physical properties of the obtained filaments.

[Example 4]
70 parts by mass of 4-methyl-1-pentene/α-olefin copolymer (A-1) as a resin composition of the core layer, thermoplastic elastomer (B-1) (Mitsui Chemicals, Inc., trade name Mirastomer 5030NS) , Melting point: 162° C., MFR: 25 g/10 min), and 30 parts by mass of isotactic polypropylene (C-1) (a product of Prime Polymer Co., Ltd., a product name Prime Polypro (registered trademark)) as a resin for the surface layer. F107, melting point: 162° C., MFR: 7 g/10 min), and the filament was obtained by spinning in the same manner as in Example 1 except that the draw ratio and the core layer/surface layer ratio were adjusted as shown in Table 1. .. Table 1 shows the evaluation results of physical properties of the obtained filaments.

[Comparative Example 1]
A 4-methyl-1-pentene/α-olefin copolymer (A-1) was used for both the core layer and the surface layer and was spun in the same manner as in Example 1 to obtain filaments. Table 1 shows the evaluation results of physical properties of the obtained filaments.

<Comparative example 2>
An example using isotactic polypropylene (C-1) (manufactured by Prime Polymer Co., Ltd., product name Prime Polypro (registered trademark) F107, melting point: 162° C., MFR: 7 g/10 minutes) was used for both the core layer and the surface layer. A filament was obtained by spinning in the same manner as in 1. Table 1 shows the evaluation results of physical properties of the obtained filaments.

As is clear from the above table, the polyolefin-based multi-layer filaments (Examples 1 to 4) within the scope of the present invention have 4-methyl-1-pentene/α-olefin copolymerization having a tan δ peak near room temperature. Since the combined layer (A) is contained in the core layer (Y) and polypropylene is used as the surface layer (Z), the effect as a multi-layer filament, that is, low dry heat dimensional change and low tackiness are excellent. It is understood that the above-mentioned two performances are inferior in the 4-methyl-1-pentene/α-olefin copolymer (A) filament which does not take the multilayer structure of Comparative Example 1 which is out of the scope of the present invention. Moreover, the tensile breaking elongation is not sufficient in a single-layer filament in which the 4-methyl-1-pentene/α-olefin copolymer (A) is not used in the core layer (Comparative Example 2), and the tan δ peak is around room temperature. Since it does not contain the component that it has, it is expected that stress absorbency around room temperature will not be effectively exhibited.

Claims (3)

A spun yarn containing a polyolefin multilayer filament,
The polyolefin multilayer filament,
A core layer (Y) made of a resin composition containing 4-methyl-1-pentene/α-olefin copolymer (A) satisfying the following requirements (a) to (c):
Consists of ethylene-based polymer, propylene-based polymer, butene-based polymer and 4-methyl-1-pentene-based polymer (excluding 4-methyl-1-pentene/α-olefin copolymer (A)) A polyolefin multilayer filament comprising a surface layer (Z) comprising at least one thermoplastic resin selected from the group:
A spun yarn characterized in that the filament has an absolute value of dry heat dimensional change rate of 10% or less measured according to JIS L1013.
Requirement (a); the copolymer (A) is derived from a structural unit (i) derived from 4-methyl-1-pentene and α-olefin (excluding 4-methyl-1-pentene). It is composed of 60 to 90 mol% of the structural unit (i) and 10 to 40 mol% of the structural unit (ii) with the total of the structural unit (ii) being 100 mol %.
Requirement (b); the intrinsic viscosity [η] measured in decalin at 135°C is in the range of 0.5 to 5.0 dL/g.
Requirement (c); density (measured by ASTM D1505) is in the range of 870 to 830 kg/m ³ . The spun yarn according to claim 1, which has a peel force of 10 N/10 mm or less after heat-treating the polyolefin multilayer filament at 50°C for 3 days. The spun yarn according to claim 1 or 2, wherein the 4-methyl-1-pentene/α-olefin copolymer (A) satisfies the following requirement (d).
Requirement (d); the tan δ peak temperature obtained by performing dynamic viscoelasticity measurement at a frequency of 10 rad/s (1.6 Hz) in the temperature range of −40 to 150° C. is 0° C. or higher and 40° C. or lower.