JP2015094054A - Fiber and nonwoven fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fiber and a nonwoven fabric which has a specified fineness and allows stable spinning, although containing an amorphous thermoplastic resin composition, and is excellent in strength and heat resistance.SOLUTION: A fiber contains an amorphous thermoplastic resin composition (I) which has a structure derived from an aromatic vinyl monomer, a glass transition temperature (Tg) of 90°C or higher and a reduced viscosity (ηsp/c) at 30°C in 2-butanone, an acetone soluble, of 0.3-0.6 dl/g. The fiber has a fineness of 1-25 dtex.

Description

  The present invention relates to fibers and nonwoven fabrics.

  Conventionally, polyolefins such as polypropylene, polyesters such as polyethylene terephthalate, etc. have been widely used for the fibers constituting the nonwoven fabric. These were mainly used for diapers and masks. However, in recent years, there has been an increasing demand for nonwoven fabrics in applications where strength and heat resistance are required. For this reason, resins for nonwoven fabrics that are more excellent in heat resistance are desired, but polyolefins and polyesters have not been sufficient.

  As an example in which a material other than the polyolefin or polyester is applied, it has been proposed to use a resin composition obtained by mixing an ABS resin (acrylonitrile-butadiene-styrene copolymer resin) and a novolac-type phenol resin for the production of fibers (for example, , See Patent Document 1). In Patent Document 1, it is clearly stated that the ABS resin has a viscosity that is not suitable for melt spinning, and that it has not been able to find an ABS resin that has sufficient spinnability and can obtain homogeneous fibers. Yes. On the other hand, Patent Document 2 describes a fiber made of PVC.

JP-A-2005-232634 Japanese Patent No. 3613960

  The reason why fibers of sufficient quality cannot be obtained from polyolefin or polyester is considered to be because the glass transition temperature (Tg) is low. Examples of the resin having a high glass transition temperature include styrene-based amorphous resins such as polystyrene and ABS resin. These styrene-based amorphous resins may be used in injection molding, extrusion molding, blow molding, and the like. Many are not suitable for spinning applications, as described in Patent Document 1. Moreover, since PVC used in Patent Document 2 has a low Tg as compared with a styrene-based amorphous resin, the heat resistance is still insufficient. As described above, the techniques described in Patent Documents 1 and 2 cannot obtain fibers that can not only stably spin but also exhibit sufficient strength and heat resistance.

  The present invention has been made in view of the above-mentioned problems, and in spite of including an amorphous thermoplastic resin composition, it is possible to perform stable spinning at a specific fineness, and a fiber excellent in strength and heat resistance. And it aims at providing a nonwoven fabric.

  As a result of intensive studies, the present inventors have obtained an amorphous thermoplastic resin composition having a glass transition temperature in a specific temperature range and a reduced viscosity (ηsp / c) of acetone-soluble content in a specific range. The present inventors have found that the above-mentioned problems can be solved by using a fiber containing the present invention, and have completed the present invention.

That is, the present invention is as follows.
[1]
Reduced viscosity (ηsp / c) at 30 ° C. in 2-butanone having a structure derived from an aromatic vinyl monomer and having a glass transition temperature (Tg) of 90 ° C. or higher and an acetone-soluble component. ) Containing 0.3 to 0.6 dl / g of the amorphous thermoplastic resin composition (I),
A fiber having a fineness of 1 dtex or more and 25 dtex or less.
[2]
The fiber according to [1], wherein the amorphous thermoplastic resin composition (I) has a structure derived from a vinyl cyanide monomer and an aromatic vinyl monomer.
[3]
The fiber according to [1] or [2], wherein the proportion of the vinyl cyanide monomer contained in the acetone-soluble component of the amorphous thermoplastic resin composition (I) is 15 to 50% by mass.
[4]
[1] to [1], wherein the amorphous thermoplastic resin composition (I) has a structure derived from a vinyl cyanide monomer, an aromatic vinyl monomer, and an acrylate monomer. 3] The fiber according to any one of [3].
[5]
The fiber according to any one of [1] to [4], wherein the amorphous thermoplastic resin composition (I) contains 0 to 15% by mass of a rubbery polymer.
[6]
A nonwoven fabric obtained from the fiber according to any one of [1] to [5].

  ADVANTAGE OF THE INVENTION According to this invention, although it contains an amorphous thermoplastic resin composition, while being able to spin stably with a specific fineness, the fiber and nonwoven fabric excellent in intensity | strength and heat resistance can be provided. .

  DESCRIPTION OF EMBODIMENTS Hereinafter, a mode for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. However, the present invention is not limited to this, and various modifications can be made without departing from the gist thereof. Is possible.

[fiber]
The fiber according to the present embodiment has a structure derived from an aromatic vinyl monomer, has a glass transition temperature (Tg) of 90 ° C. or higher, and is 2-butanone in an acetone-soluble component, 30 Amorphous thermoplastic resin composition (I) having a reduced viscosity (ηsp / c) at 0.3 ° C. of not less than 0.3 dl / g and not more than 0.6 dl / g is included. Furthermore, the fiber according to the present embodiment has a fineness of 1 dtex or more and 25 dtex or less. Since the fiber according to this embodiment includes the amorphous thermoplastic resin composition, the fiber according to the present embodiment can be stably spun at a specific fineness, and has high strength and heat resistance. Excellent.

(Amorphous thermoplastic resin composition)
As described above, the amorphous thermoplastic resin composition (I) constituting the fiber according to this embodiment includes a structure derived from an aromatic vinyl monomer and has a glass transition temperature (Tg) of 90 ° C. or higher. The reduced viscosity (ηsp / c) at 30 ° C. in 2-butanone with acetone-soluble content is 0.3 to 0.6 dl / g.

  The amorphous thermoplastic resin constituting the amorphous thermoplastic resin composition (I) in the present embodiment contains at least an aromatic vinyl monomer as a monomer. Here, the “amorphous thermoplastic resin” refers to a thermoplastic resin that does not have a crystal structure. Specifically, when the endothermic amount is measured using a differential scanning calorimeter (DSC), the glass transition temperature peak is observed, but the melting point peak is not observed. The aromatic vinyl monomer is not particularly limited, and examples thereof include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, o-ethylstyrene, p-ethylstyrene, and pt-butylstyrene. And vinyl naphthalene. Of these, styrene and α-methylstyrene are preferable from the viewpoints of spinnability and strength. These aromatic vinyl monomers may be used alone or in combination of two or more.

  The amorphous thermoplastic resin preferably further contains a vinyl cyanide monomer as a monomer. In other words, it is preferable that the amorphous thermoplastic resin composition (I) in this embodiment has a structure derived from a vinyl cyanide monomer and an aromatic vinyl monomer. Examples of the vinyl cyanide monomer include acrylonitrile, methacrylonitrile, ethacrylonitrile and the like. Of these, acrylonitrile is preferred from the viewpoint of strength and heat resistance. Moreover, these vinyl cyanide monomers may be used alone or in combination of two or more.

  When the amorphous thermoplastic resin contains a vinyl cyanide monomer, the content of the vinyl cyanide monomer contained in the acetone-soluble component of the amorphous thermoplastic resin composition (I) Is preferably 15% by mass or more and 50% by mass or less, more preferably 25% by mass or more and 45% by mass or less, and further preferably 30% by mass or more and 40% by mass or less. When the proportion of the vinyl cyanide monomer is 15% by mass or more, the heat resistance tends to be more excellent. Further, when the amount is 50% by mass or less, more stable spinning tends to be possible. Content of the said vinyl cyanide-type monomer can be measured by the method as described in the Example mentioned later.

  The amorphous thermoplastic resin preferably contains an acrylate monomer as a monomer. Furthermore, the amorphous thermoplastic resin more preferably contains a vinyl cyanide monomer, an aromatic vinyl monomer, and an acrylate monomer as monomers. In other words, the amorphous thermoplastic resin composition (I) in this embodiment has a structure derived from a vinyl cyanide monomer, an aromatic vinyl monomer, and an acrylate monomer. It is more preferable. Examples of the acrylate monomer include, but are not limited to, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, and n-butyl (meth) acrylate. , T-butyl (meth) acrylate, n-hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) acryl Examples thereof include unsaturated carboxylic acid alkyl ester monomers such as 2,3,4,5,6-pentahydroxyhexyl acid and 2,3,4,5-tetrahydroxypentyl (meth) acrylate. Of these, n-butyl acrylate is preferred. Moreover, these acrylic acid ester monomers may be used alone or in combination of two or more.

  The amorphous thermoplastic resin composition (I) in the present embodiment has a glass transition temperature (Tg) of 90 ° C. or higher. The glass transition temperature is preferably 100 ° C. or higher, and more preferably 105 ° C. or higher. When the glass transition temperature is 90 ° C. or higher, the heat resistance is improved. The glass transition temperature can be measured using a differential scanning calorimeter (DSC).

  Specific examples of the amorphous thermoplastic resin in the present embodiment include, but are not limited to, polystyrene (GPPS), high impact polystyrene (HIPS), methyl methacrylate-styrene copolymer (MS resin), methyl methacrylate-butadiene. -Styrene copolymer (MBS resin), methyl methacrylate-acrylonitrile-styrene copolymer (MAS resin), acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile- Examples include acrylate-styrene copolymer (ASA resin), acrylonitrile-EPDM-styrene copolymer (AES resin), and acrylonitrile-chlorinated polyethylene-styrene copolymer (ACS resin). These may be used alone or in combination of two or more.

  The amorphous thermoplastic resin preferably contains the rubber polymer (i) in an amount of more than 0% by mass to 15% by mass, and more preferably in an amount of more than 0% by mass to 10% by mass. The rubbery polymer (i) is a polymer containing at least the rubber component (a), and a homopolymer of the rubber component (a) or one or more monomers in the rubber component (a). Examples thereof include a copolymer obtained by copolymerization. When the content of the rubbery polymer (i) is 15% by mass or less, it tends to be superior in strength and more stable spinning. The content of the rubbery polymer can be determined by component analysis using FT-IR.

  As the rubber component (a), one having a glass transition temperature (Tg) of 0 ° C. or lower can be used. Specific examples include, but are not limited to, polybutadiene, styrene-butadiene copolymer rubber, acrylonitrile-butadiene copolymer rubber, polyisoprene, polychloroprene, styrene-butadiene block copolymer rubber, and styrene-isoprene block copolymer rubber. , Conjugated diene rubbers such as ethylene-propylene-diene terpolymer rubber, acrylic rubbers such as polybutyl acrylate, ethylene-propylene rubber, silicon rubber, silicon-acrylic composite rubber and hydrogenated products thereof can do. Among these, conjugated diene polymers are preferable, and polybutadiene, styrene-butadiene copolymer rubber, and acrylonitrile-butadiene copolymer rubber are particularly preferable. Of these, polybutadiene, styrene-butadiene copolymer, styrene-butadiene block copolymer, and acrylonitrile-butadiene copolymer are preferable from the viewpoint of strength.

  In addition, as the rubber component (a), those having a volume average particle diameter of 0.05 μm or more and 0.4 μm or less can be used. The volume average particle diameter of the rubber component (a) is preferably from 0.15 μm to 0.35 μm, and more preferably from 0.15 μm to 0.30 μm. The volume average particle diameter can be obtained by image analysis of a transmission electron microscope (TEM) photograph for an arbitrary range of 20 μm × 40 μm in the fiber according to the present embodiment.

  When the rubber polymer (i) is a copolymer obtained by copolymerizing one or more monomers with the rubber component (a), the monomer copolymerized with the rubber component (a) is as follows: Without limitation, aromatic vinyl monomers, vinyl cyanide monomers, and other copolymerizable monomers can be used.

  The aromatic vinyl monomer copolymerized with the rubber component (a) is the same as that described above as a specific example of the aromatic vinyl monomer contained in the amorphous thermoplastic resin in the present embodiment. Can do.

  The vinyl cyanide monomer copolymerized with the rubber component (a) is the same as that described above as a specific example of the vinyl cyanide monomer that can be included in the amorphous thermoplastic resin in the present embodiment. can do.

  Examples of other monomers copolymerizable with the rubber component (a) include, but are not limited to, unsaturated carboxylic acid alkyl ester monomers, maleic anhydride, N-phenylmaleimide, N-methylmaleimide, and the like. N-substituted maleimide monomers, glycidyl group-containing monomers such as glycidyl methacrylate, and the like. These may be used alone or in combination of two or more.

  Examples of the method for producing the rubber polymer (i) include emulsion polymerization, suspension polymerization, bulk polymerization, solution polymerization, and a combination of these polymerization methods. Specific examples include an emulsion graft polymerization method in which a monomer is graft polymerized to the latex of the rubber component (a) produced by emulsion polymerization. The polymer obtained by the above emulsion graft polymerization method is a graft polymer (G), a rubber polymer (A) obtained by graft polymerization of a monomer to a rubber component (a), and a graft polymer to the rubber component (a). A graft unreacted copolymer (B) in which a monomer that has not been copolymerized is polymerized is included. Any of continuous, batch, and semi-batch methods can be used.

  The ratio of the monomer graft-copolymerized to the rubber component (a) produced in the process of producing the graft copolymer (G) (graft ratio) is preferably 20 to 200 parts by mass with respect to 100 parts by mass of the rubber component, More preferably, it is 25-100 mass parts, Furthermore, 30-70 mass parts is preferable. The graft ratio is obtained by using acetone to remove the soluble component (acetone soluble component), taking out the graft copolymer (G) as an insoluble component, and using a Fourier transform infrared spectrophotometer (FT-IR) to obtain a rubber component. And other components can be analyzed and obtained based on the results.

  Furthermore, the amorphous thermoplastic resin composition (I) has a reduced viscosity (ηsp / c) at 30 ° C. in 2-butanone of acetone-soluble content of 0.3 dl / g or more and 0.6 dl / g or more. Yes, 0.35 dl / g or more and 0.55 dl / g or less is preferable, and 0.4 dl / g or more and 0.5 dl / g or less is more preferable. By setting the reduced viscosity to 0.3 dl / g or more, excellent strength and heat resistance can be obtained. Moreover, stable spinning becomes possible by setting it to 0.6 dl / g or less. In addition, the reduced viscosity here can be measured by the method as described in the Example mentioned later.

(Other compounding agents and additives)
Furthermore, you may use an additive as a raw material for the amorphous thermoplastic resin composition (I) which concerns on this embodiment as needed. Examples of the additive include, but are not limited to, for example, phosphite-based, hindered phenol-based, benzotriazole-based, benzophenone-based, benzoate-based, and cyanoacrylate-based UV absorbers and antioxidants; higher fatty acids and acid esters. And acid amides, lubricants and plasticizers such as higher alcohols; release agents such as montanic acid and its salts, esters, half esters, stearyl alcohol, stellar amide and ethylene wax; Anti-coloring agents such as phosphates; Nucleating agents; Antistatic agents such as amines, sulfonic acids, and polyethers; 1,3-phenylenebis (2,6-dimethylphenyl phosphate), tetraphenyl-m- Lithium bisphosphate, phenoxyphosphoryl, phenoxyphosphazene, etc. And a halogen-based flame retardants; system flame retardant. From the viewpoint of spinnability of the thermoplastic resin composition constituting the fiber according to the present embodiment, it is preferable to include a lubricant.

  Examples of the lubricant include, but are not limited to, aliphatic metal salts, polyolefins, polyester elastomers, polyamide elastomers, and the like.

  The fatty acid metal salt is a salt of a metal and a fatty acid containing one or more selected from sodium, magnesium, calcium, aluminum, and zinc. Specific examples of the fatty acid metal salt include, but are not limited to, for example, sodium stearate, magnesium stearate, calcium stearate, aluminum stearate (mono, di, tri), zinc stearate, sodium montanate, montanic acid Examples include calcium, calcium ricinoleate, and calcium laurate. Among the above, stearic acid-based metal salts such as sodium stearate, magnesium stearate, calcium stearate, and zinc stearate are preferable. Among the stearic acid-based metal salts, specifically, calcium stearate is more preferable.

  Although not limited to the following as said polyolefin, For example, the composition produced | generated from at least 1 or more types, such as ethylene, propylene, an alpha olefin, is mentioned, These are the compositions induced | guided | derived from this composition as a raw material Including. Specific examples include, but are not limited to, polypropylene, ethylene-propylene copolymer, polyethylene (high density, low density, linear low density), oxidized polyolefin, and graft polymerized polyolefin. Of these, oxidized polyolefin wax and polyolefin grafted with styrene resin are preferred, more preferably polypropylene wax, polyethylene wax, oxidized polypropylene wax, oxidized polyethylene wax, acrylonitrile-styrene copolymer grafted polypropylene, acrylonitrile- Styrene copolymer grafted polyethylene, styrene polymer grafted polypropylene, and styrene polymer grafted polyethylene.

  Examples of the polyester elastomer include, but are not limited to, for example, polycondensation of a dicarboxylic acid compound and a dihydroxy compound, ring-opening polycondensation of a polycondensation lactone compound of an oxycarboxylic acid compound, or polycondensation of a mixture of these components. And polyester obtained by the above. Either a homopolyester or a copolyester may be used.

  Examples of the dicarboxylic acid compound include, but are not limited to, terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, and diphenyl-4,4-dicarboxylic acid. , Aromatic dicarboxylic acids such as diphenoxyethanedicarboxylic acid, sodium 3-sulfoisophthalate, and aliphatic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, dicyclohexyl-4,4-dicarboxylic acid , Diphenyl ether dicarboxylic acid, diphenylethane dicarboxylic acid, succinic acid, oxalic acid, adipic acid, sebacic acid, dodecanedicarboxylic acid and other aliphatic dicarboxylic acids, and mixtures of these dicarboxylic acids. Haloge And substituted are also included. These dicarboxylic acid compounds can also be used in the form of an ester-forming derivative, for example, a lower alcohol ester such as dimethyl ester. In this embodiment, these dicarboxylic acid compounds can be used alone or in combination of two or more. Of these, terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, sebacic acid, adipic acid and dodecanedicarboxylic acid are preferred.

  Examples of the dihydroxy compound include, but are not limited to, ethylene glycol, propylene glycol, butanediol, neopentyl glycol, butenediol, hydroquinone, resorcin, dihydroxy diphenyl ether, cyclohexane diol, hydroquinone, resorcin, dihydroxy diphenyl ether, cyclohexane diol, 2,2-bis (4-hydroxyphenyl) propane and the like, and these polyoxyalkylene glycols and their alkyl, alkoxy or halogen-substituted products are exemplified. These dihydroxy compounds can be used alone or in combination of two or more.

  Examples of the oxycarboxylic acid compound include, but are not limited to, oxybenzoic acid, oxynaphthoic acid, diphenyleneoxycarboxylic acid, and the like, and these alkyl, alkoxy, and halogen substituted products are also included. These oxycarboxylic acid compounds can be used alone or in combination of two or more. A lactone compound such as ε-caprolactone can also be used for producing a polyester elastomer.

Examples of the polyamide elastomer include, but are not limited to, for example, aminocarboxylic acids or lactams having 6 or more carbon atoms, nylon mn salts having m + n of 12 or more, and the hard segment (X) is limited to the following. For example, aminocarboxylic acids such as ω-aminocaproic acid, ω-aminoenanoic acid, ω-aminocaprylic acid, ω-aminobergonic acid, ω-aminocapric acid, 11-aminoundecanoic acid, 12-aminododecanoic acid; caprolactam Lactams such as laurolactam, nylon 6,6, nylon 6,10, nylon 6,12, nylon 11,6, nylon 11,10, nylon 12,6, nylon 11,12, nylon 12,10, nylon 12, Nylon salts such as 12. In addition, the soft segment (Y) such as polyol includes polyethylene glycol, poly (1,2- and 1,3-propylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, and ethylene oxide. Examples thereof include a block or random copolymer of propylene oxide and a block or random copolymer of ethylene oxide and tetrahydrofuran. The number average molecular weight of these soft segments (Y) can be 2.0 × 10 ^{2 to} 6.0 × 10 ^3, and preferably 2.5 × 10 ^{2 to} 4.0 × 10 ³ . The number average molecular weight can be measured as a styrene equivalent molecular weight by comparison with standard polystyrene by gel permeation chromatography (GPC). Note that both ends of poly (alkylene oxide) glycol may be aminated or carboxylated.

  When a lubricant is added to the amorphous thermoplastic resin composition (I) in this embodiment, an acid-modified or epoxy-modified modified resin may be mixed for the purpose of improving the compatibility. Further, a part of the amorphous thermoplastic resin (I) may be acid-modified or epoxy-modified within a range that does not impair the sharpness. For example, the amorphous thermoplastic resin (I) is a copolymer of a monomer selected from an aromatic vinyl monomer, a vinyl cyanide monomer, and an acrylic monomer. In the case of polymers, those obtained by copolymerizing a vinyl monomer containing a carboxyl group or a glycidyl group can be used.

  Examples of the vinyl monomer containing a carboxyl group include, but are not limited to, unsaturated compounds containing a free carboxyl group such as acrylic acid, crotonic acid, cinnamic acid, itaconic acid, maleic acid, maleic anhydride, anhydrous Examples thereof include unsaturated compounds containing an acid anhydride-type carboxyl group such as itaconic acid, chloromaleic anhydride, and citraconic anhydride. Among these, acrylic acid, methacrylic acid, and maleic anhydride are preferred.

  Examples of the vinyl monomer containing a glycidyl group include, but are not limited to, glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, methyl glycidyl ether, methyl glycidyl methacrylate, and the like. Among these, glycidyl methacrylate Is preferred.

(Method for producing amorphous thermoplastic resin composition (I))
The amorphous thermoplastic resin composition (I) constituting the fiber according to the present embodiment is a thermoplastic resin composition such as a monoaxial or biaxial vented extruder, plastmill, kneader, Banbury mixer, Brabender. It can manufacture using the various mixing apparatuses generally used for manufacture.

(Fibers obtained from amorphous thermoplastic resin composition (I))
The fiber according to the present embodiment includes the amorphous thermoplastic resin composition (I), in other words, can be obtained from the amorphous thermoplastic resin composition (I). The fineness of the fiber according to this embodiment is 1 dtex or more and 25 dtex or less. When the fineness is 1 dtex or more, stable spinning is possible. From the viewpoint of further improving the stability of spinning, it is preferably 4 dtex or more. Moreover, the outstanding intensity | strength and heat resistance are obtained by being 25 dtex or less. From the viewpoint of ensuring better strength and heat resistance, the fineness is preferably 20 dtex or less, and more preferably 15 dtex or less. In addition, the said fineness can be measured by the method as described in the Example mentioned later.

[Fiber manufacturing method]
The fiber production method according to the present embodiment, that is, the spinning method is not limited to the following, but known methods such as melt spinning, dry spinning, and wet spinning can be employed, and melt spinning is preferred. As an apparatus used for melt spinning, a general melt spinning apparatus such as a single-screw extruder or a twin-screw extruder can be used.

  The spinning temperature in melt spinning is not limited to the following, but the temperature range is preferably adjusted to 220 to 300 ° C. from the viewpoint of enabling more stable spinning. When the spinning temperature is 220 ° C. or higher, the melt viscosity necessary for stable spinning tends to be obtained. Moreover, when it is 300 degrees C or less, it exists in the tendency which can suppress effectively the intensity | strength reduction and discoloration of resin by a heat history.

  Although it does not specifically limit as a nozzle single hole diameter of the melt spinning apparatus which can be used, Preferably it is 0.01 mm-1 mm (phi), More preferably, it is 0.05 mm-0.5 mm (phi).

  The single hole discharge amount of the melt spinning apparatus that can be used is not particularly limited as long as stable spinning is possible, but is preferably 0.1 g / min / hole to 10 g / min / hole.

  The fibers of the present embodiment obtained as described above may be drawn and used for adjusting the fineness and strength. A generally used method can be used as the stretching method. The temperature at the time of extending | stretching becomes like this. Preferably it is 100 to 180 degreeC, More preferably, it is 110 to 150 degreeC.

  The fiber according to the present embodiment may be a single fiber or a composite fiber having a sheath core structure. In the case of a composite fiber, the sheath and the core may be concentric or eccentric. Moreover, although the amorphous thermoplastic composition in this embodiment may be used as any raw material of a sheath and a core, it is preferably used as a sheath.

  The fibers according to this embodiment may be used alone or in combination with other fibers. Examples of other fibers that can be combined include, but are not limited to, polyolefin fibers, polyester fibers, acrylic fibers, polyamide fibers, polyvinyl alcohol fibers, polyurethane fibers, and the like.

[Nonwoven fabric]
The fibers of the present embodiment obtained as described above can be used as general fibers, but are preferably used as fibers constituting the nonwoven fabric. That is, the nonwoven fabric which concerns on this embodiment is obtained from the fiber which concerns on this embodiment. Such a nonwoven fabric can exhibit excellent strength and heat resistance. Specific methods for producing the nonwoven fabric according to the present embodiment are not limited to the following, but for example, existing methods such as a dry method, a wet method, a spunbond method, a melt blown method, and the like can be used. Of these, the spunbond method and the melt blown method are preferable.

  Existing methods such as a chemical bond method, a thermal bond method, a needle punch method, and a spun lace method can be used as a bonding method when forming a web using the fibers according to the present embodiment.

  The nonwoven fabric according to this embodiment obtained as described above can be post-processed by a known method such as dyeing, laminating, coating, or plating.

Basis weight of the nonwoven fabric of the present embodiment can be adjusted to any range depending on the application, preferably ^{1g / m 2 ~10000g / m 2} , more preferably ^{10g / m 2 ~1000g / m 2} . When the basis weight is 1 g / m ² or more, the strength tends to be excellent. Moreover, it exists in the tendency which is excellent in a texture by being 10,000 g / m < ² > or less. The basis weight can be determined by measuring the mass per certain area.

  Although the thickness of the nonwoven fabric of this embodiment can be used by arbitrary thickness by a use, Preferably it is 0.1 mm-100 mm, More preferably, it is 0.2 mm-50 mm.

  The nonwoven fabric of this embodiment obtained as described above may be used singly or may be used by laminating two or more. In the case of using the laminated layers, some of the nonwoven fabrics of this embodiment may be laminated and used, or may be laminated with a nonwoven fabric made of another material.

  Hereinafter, although this embodiment is described more specifically using examples and comparative examples, this embodiment is not limited to the following examples.

  In this example, the following raw materials were used.

[Copolymer (A)]
(Copolymer (A-1))
As a result of composition analysis using a Fourier transform infrared spectrophotometer (FT-IR) (IR-410, manufactured by JASCO Corporation), it was 39.9% by mass of acrylonitrile and 60.1% by mass of styrene, and the reduced viscosity was An AS resin of 0.47 dl / g was used. In the above FT-IR, using a calibration curve created using the peak value of a sample containing an unsaturated nitrile monomer having a known concentration, the ratio of the unsaturated nitrile monomer is determined and specified. did. The mass of the rubbery polymer was specified in the same manner.

(Copolymer (A-2))
As a result of composition analysis using FT-IR, an AS resin having acrylonitrile of 29.8% by mass, styrene of 70.2% by mass and a reduced viscosity of 0.65 dl / g was used.

(Copolymer (A-3))
As a result of the composition analysis using FT-IR, AS resin having 25.2% by mass of acrylonitrile and 74.8% by mass of styrene and a reduced viscosity of 0.46 dl / g was used.

(Copolymer (A-4))
As a result of the composition analysis using FT-IR, they were 39.1% by mass of acrylonitrile, 51.1% by mass of styrene, and 9.8% by mass of butyl acrylate. Further, AS resin having a reduced viscosity of 0.42 dl / g was used.

(Copolymer (A-5))
As a result of the composition analysis using FT-IR, they were 29.7% by mass of acrylonitrile, 63.5% by mass of styrene, and 6.8% by mass of butyl acrylate. An AS resin having a reduced viscosity of 0.45 dl / g was used.

(Copolymer (A-6))
As a result of composition analysis using FT-IR, they were 29.9% by mass of acrylonitrile and 70.1% by mass of styrene. Further, AS resin having a reduced viscosity of 0.28 dl / g was used.

[Copolymer (B)]
(Copolymer (B-1))
Graft copolymer mass 71% (acrylonitrile 11.5 mass%, butadiene 70.4 mass%, styrene 18.0%, graft ratio 42.0%), graft unreacted copolymer mass 29% (vinyl cyanide-based) Monomer content: 11.4% by mass, aromatic vinyl monomer content: 17.6% by mass, reduced viscosity 0.41 dl / g) ABS resin was used.

(Copolymer (B-2))
Graft copolymer mass 73.4% (acrylonitrile 8.6 mass%, butadiene 68.1 mass%, styrene 23.3%, graft ratio 46.8%), graft unreacted copolymer mass 26.6% ( An ABS resin having a vinyl cyanide monomer content of 27.1% by mass, an aromatic vinyl monomer content of 72.9% by mass, and a reduced viscosity of 0.38 dl / g) was used.

[PET]
TRN-8580FC manufactured by Teijin Limited was used.

[PP]
Nippon Polypro Co., Ltd. Novatec SA3A was used.

[PVC]
TK-1000 manufactured by Shin-Etsu Chemical Co., Ltd. was used.

  Samples of Examples 1 to 5 and Comparative Examples 1 to 5 were obtained with the formulation as shown in Table 1. Examples 2-5 and Comparative Example 1 were kneaded at a cylinder set temperature of 240 ° C. using a single screw extruder (HS-30, manufactured by Ishinaka Iron Works Co., Ltd.) after blending with the formulation in Table 1. A pellet of the thermoplastic resin composition was obtained.

(1) Glass transition temperature measurement method Using a differential scanning calorimeter DSC8500 (manufactured by PerkinElmer), the glass transition temperature was measured under the condition of a temperature rising rate of 20 ° C./min.

(2) Method for measuring reduced viscosity (2.1) Method for extracting acetone-soluble matter Two dried centrifuge tubes were prepared per sample. First, the centrifuge tube was allowed to cool in a desiccator for 15 minutes or more, and then precisely weighed to 0.1 mg with an electronic balance. Next, about 1 g was cut from the thermoplastic resin composition obtained as described above, weighed into a centrifuge tube, and precisely weighed to 0.1 mg. In addition, about 20 mL of acetone was collected with a graduated cylinder, placed in a centrifuge tube, sealed with a silicon stopper, and shaken for 2 hours with a shaker. After shaking, the sample adhering to the silicon stopper was dropped into a centrifuge tube using a small amount of acetone. Next, the two centrifuge tubes were set diagonally to the rotor of a Hitachi high-speed cooling centrifuge manufactured by Hitachi Koki Co., Ltd. The Hitachi high-speed cooling centrifuge was operated and centrifuged at a rotational speed of 20000 rpm for 60 minutes. After completion of the centrifugation, the sedimentation tube was removed from the rotor, and the supernatant was decanted. The supernatant was dried at 80 ° C. for 1 hour and then dried under reduced pressure at 100 ° C. for 1 hour to obtain an acetone-soluble component of the amorphous thermoplastic resin composition. In Comparative Examples 2 to 3, no acetone-soluble component was obtained.

(2.2) Measuring method of reduced viscosity 0.50 g of acetone-soluble matter obtained by the above method was dissolved in 100 ml of 2-butanone. About this solution, the reduced viscosity was obtained by measuring the outflow time in a Cannon-Fenske type | mold capillary tube at 30 degreeC. As described above, Comparative Examples 2-3 could not measure the reduced viscosity.

(3) Spinnability evaluation method Spinning was performed to a fineness of 1 to 25 dtex using a melt spinning apparatus having a nozzle diameter of 0.1 mmφ. The spinnability of the obtained fiber was evaluated based on the following criteria.
○ Stable spinning was possible and uniform fibers could be obtained.
Δ: One or two fibers per hour were cut during spinning, but a uniform fiber could be obtained.
X Three or more fibers were cut frequently every hour during spinning, and uniform fibers could not be obtained.

(4) Fineness evaluation method The mass of 20 samples obtained by cutting the fiber obtained in (3) into 50 mm was measured. The fineness was calculated by the following formula.
Fineness (dtex) = Sample mass (g) /0.05 (m) / 20 × 1000 (m)

(5) Strength Evaluation Method 10 g of the fiber obtained in (3) was placed in a PP nonwoven fabric having a size of 80 mm × 90 mm × 1 mmt and a basis weight of 35 g / m ² and sealed. The thickness at this time was 40 mm. The sample was allowed to stand for 24 hours under a temperature of 23 ° C. and a humidity of 50% so that the thickness was ½. Thereafter, the load was released and left for 3 hours. The ratio of the thickness restored after repeating this 10 times to the compressed thickness (20 mm) was evaluated as strength (%).

(6) Heat resistance evaluation method A sample similar to (5) was loaded under a temperature of 80 ° C. so as to have a thickness of 1/2 and left for 24 hours. Thereafter, the load was released, and the ratio of the restored thickness to the compressed thickness (20 mm) after standing for 3 hours in an environment of temperature 23 ° C. and humidity 50% was evaluated as heat resistance (%).

  Table 1 shows the results of evaluating the samples corresponding to Examples 1 to 5 and Comparative Examples 1 to 5 obtained as described above as described in (1) to (6) above. In addition, the rubber-like polymer in Table 1 is expressed by mass% with respect to the raw material of the resin composition.

  From Table 1, it can be seen that the fibers of Examples 1 to 5 have better strength and heat resistance than the fibers of Comparative Examples 1 to 5.

  Since the fiber of the present invention is excellent in strength and heat resistance, the fiber itself or the material constituting the nonwoven fabric is industrially used in hygiene / medical use, vehicle use, civil engineering and building use, agricultural and horticultural use, general industrial use, etc. Has availability.

Claims (6)

Reduced viscosity (ηsp / c) at 30 ° C. in 2-butanone having a structure derived from an aromatic vinyl monomer and having a glass transition temperature (Tg) of 90 ° C. or higher and an acetone-soluble component. ) Containing 0.3 to 0.6 dl / g of the amorphous thermoplastic resin composition (I),
A fiber having a fineness of 1 dtex or more and 25 dtex or less.   The fiber according to claim 1, wherein the amorphous thermoplastic resin composition (I) has a structure derived from a vinyl cyanide monomer and an aromatic vinyl monomer.   The fiber of Claim 1 or 2 whose ratio of the vinyl cyanide monomer contained in the acetone soluble part of the said amorphous thermoplastic resin composition (I) is 15-50 mass%.   The amorphous thermoplastic resin composition (I) has a structure derived from a vinyl cyanide monomer, an aromatic vinyl monomer and an acrylate monomer. The fiber of any one of these.   The fiber according to any one of claims 1 to 4, wherein the amorphous thermoplastic resin composition (I) contains 0 to 15% by mass of a rubbery polymer.   The nonwoven fabric obtained from the fiber of any one of Claims 1-5.