JP2000199123A - Antimicrobial fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antimicrobial fiber well durable and inexpensive by adding a specific phosphite compound to a thermoplastic resin in a specified ratio for meltingly kneading the mixture and then spinning it. SOLUTION: This fiber is obtained by adding at least one or more kinds of phosphite compounds represented by formula I (R1 is e.g. a 4-12 branched alkyl or arylalkyl; R2 is H, a 1-12C alkyl, cycloalkyl or arylalkyl; R3 is e.g. H, a 1-12C alkyl, cycloalkyl, arylalkyl; and R4 and R5 are each a 1-8C alkyl, an OH-substituted 1-4C alakyl or a compound of formula II when combined with each other, pref. compounds of formula III) to a thermoplastic resin (e.g. polyester-based or polyamide-based resin) in the content of 0.005 to 10 wt.% for meltingly kneading the mixture, followed by spinning it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD [0001] The present invention has good durability,
The present invention relates to an inexpensive antibacterial fiber having antibacterial properties.

[0002]

2. Description of the Related Art In recent years, hygiene consciousness has been increased, and it has become commonplace to provide antibacterial properties to living materials in which propagation of various bacteria is expected, and many methods for imparting antibacterial properties have been proposed.

[0003] Various antibacterial agents are used in such antibacterial products, and the compounding of the antibacterial agents to the products is also various. For example, a method is known in which fine particles of a metal or a metal compound exhibiting antibacterial properties are brought into contact with an organic polymer material as a dispersion to coat and adhere to the surface of the organic polymer (JP-A-7-97769). However, in this method of imparting antibacterial properties, only the antibacterial metal is attached to the surface,
Poor washing durability. Also, a method of forming a cross-linking structure of an antibacterial agent with a melamine resin to coat the surface (Japanese Patent Laid-Open No.
No. 4, JP-A-10-110388), processing is easy, but the washing durability is also poor.

[0004] A method of kneading an inorganic metal material represented by a silver zeolite system (Japanese Patent Laid-Open No. 5-272008, Japanese Patent Publication No. 63-54013, etc.), a method of adding a fine metal powder such as copper or zinc ( In JP-A-55-130371, the amount of zeolite having inorganic silver, copper, and zinc ions and the amount of metal powder to be supported are limited. When the zeolite is mixed in a large amount, the physical properties of the composition are reduced, and the back pressure during spinning is reduced. The increase is remarkable, and the productivity is lowered. In the case where the surface of the metal powder is coated to prevent the back pressure from increasing due to the aggregation of the metal powder, there is a problem that the antibacterial property is reduced. Further, the metal powder has a problem such as coloring due to elution of metal ions. On the other hand, as a method for incorporating an organic antibacterial agent, a quaternary ammonium salt compound (Japanese Patent Laid-Open No. 62-69883) is used.
And natural herbal antibacterial agents (Japanese Patent Application Laid-Open No. 7-216731) have been proposed, but have the problem of poor heat stability and poor versatility. As another method, a method of mixing a halogen-based phenol compound (for example, Japanese Patent Application Laid-Open No. 60-252713) has been proposed. However, since halogenated phenols need to be contained in paraffin, they are used in general-purpose thermoplastic resins. Can not.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide an inexpensive antibacterial fiber having excellent durability.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, a compound having little antibacterial activity by itself has excellent compatibility with a thermoplastic resin. The present inventors have found that an antimicrobial fiber which is inexpensive and has excellent durability can be obtained by melting and kneading a thermoplastic resin with an inexpensive compound as an active ingredient, which can prevent thermal deterioration and coloring, and completed the present invention.

That is, a first aspect of the present invention is that the content of at least one phosphite compound represented by the following general formula (I) is 0.005 to 10% by weight based on the thermoplastic resin. An antibacterial fiber obtained by melt-kneading and spinning to obtain

Embedded image (In the above formula, R ¹ represents a branched alkyl group having 4 to 12 carbon atoms, a cycloalkyl group or an arylalkyl group, and R ² represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group or R ³ represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, an arylalkyl group or —R
⁶ COOR ⁷ represents, R ⁶ represents an alkylene group having 1 to 6 carbon atoms, R7 represents an alkyl group or an aryl group having 1 to 18 carbon atoms, and R4 and R5 each independently represent 1 carbon atom. Represents an alkyl group having 8 to 8 carbon atoms, an alkyl group having 1 to 4 carbon atoms substituted with a hydroxy group, or a group having the following structure (II) in which R ⁴ and R ⁵ are combined. )

[0008]

Embedded image (In the above formula, R ¹ , R ² and R ³ are the same as in the general formula (I).)

A second aspect of the present invention is the antibacterial fiber according to the first aspect, wherein the phosphite compound of the general formula (I) is the following compound (A).

Embedded image

A third aspect of the present invention is the antibacterial fiber according to the first aspect, wherein the phosphite compound of the general formula (I) is the following compound (B).

Embedded image

In a fourth aspect of the present invention, the fiber has a core-sheath structure in cross section, and the sheath component contains 0.005 to 10% by weight of at least one phosphite compound represented by the general formula (I). %
The first resin, wherein the weight ratio of the core-sheath component is in the range of core: sheath = 50: 50 to 90:10.
The antibacterial fiber according to any one of Items 1 to 3.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The above general formula (I) in the present invention
The phosphite compound shown in (1) exhibits excellent antibacterial properties when uniformly mixed with a thermoplastic resin. The reason why the compound exhibits antibacterial properties is not well understood, but since the compound exhibits an effect of decomposing peroxides, it is considered that this causes some inhibition in bacterial metabolism and the like.

In the general formula (I) showing the phosphite compound, the branched alkyl group having 4 to 12 carbon atoms represented by R ¹ includes, for example, secondary butyl, tertiary butyl, tertiary amyl, Tertiary octyl, isodecyl, isododecyl and the like. Examples of the alkyl group having 1 to 12 carbon atoms represented by R ² and R ³ include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, amyl, sec-amyl, tert-amyl, and octyl. , Decyl, dodecyl and the like.

The arylalkyl groups represented by R ¹ , R ² and R ³ include, for example, benzyl, cumyl and the like. Similarly, examples of the cycloalkyl group include cyclopentyl, cyclohexyl, cycloheptyl and the like.

1 to 8 carbon atoms represented by R ⁴ and R ⁵
Examples of the alkyl group include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, tert-butyl, amyl, sec-amyl, tert-amyl, and octyl. Examples of the alkyl groups (1) to (4) include hydroxymethyl, hydroxyethyl, hydroxypropyl, and hydroxybutyl.

The alkylene group having 1 to 6 carbon atoms represented by R ⁶ includes, for example, methylene, ethylene, propylene, trimethylene, tetramethylene, isobutylene, pentamethylene, hexamethylene and the like.

The alkyl group having 1 to 18 carbon atoms represented by R7 includes methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl,
Pentyl, tertiary pentyl, hexyl, heptyl, octyl, tertiary octyl, 2-ethylhexyl, nonyl, isononyl, decyl, isodecyl, undecyl, dodecyl,
Tridecyl, tetradecyl, hexadecyl, octadecyl and the like can be mentioned.

The phosphite compound in the present invention is a compound represented by the above-mentioned general formula (I).
Phosphite of 2,4,6-tri-tert-butylphenol and 2-hydroxymethyl-2-ethylhexanol, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert. Tributyl-4
-Methylphenyl) pentaerythritol diphosphite, bis (2,4,6-tritert-butylphenyl) pentaerythritol diphosphite, bis (2,4-dicumylphenyl) pentaerythritol diphosphite,
Bis [2,6-di-tert-butyl-4- (2-butyloxycarbonylethyl) phenyl] pentaerythritol phosphite and the like, and preferably bis (2,6-di-tert-butyl) represented by compound (A) Butyl-4-methylphenyl) pentaerythritol diphosphite is preferred in that it has excellent compatibility with the thermoplastic resin and has excellent thermal stability.

Since the melting point of the compound is specific to the compound, the melting point of the phosphite compound contained in the present invention is not particularly limited, but the compatibility with the following thermoplastic resin is improved. It is preferable that it is -240 degreeC.

When the phosphite compound of the present invention is contained in a thermoplastic resin, its content is 0.005 to 10% by weight, preferably 0.05 to 5.0% by weight of the thermoplastic resin. % By weight, more preferably 0.1%
~ 2.0% by weight. If the content is less than 0.005% by weight, the antibacterial property cannot be sufficiently exhibited, which is not preferable.
If the content exceeds 10% by weight, the phosphite compound bleeds out, impairs the appearance of the fiber made of a thermoplastic resin, and is not preferable in terms of cost.

The thermoplastic resin in the present invention is not particularly limited, but is a general-purpose thermoplastic resin represented by a polyester resin, a polyamide resin, a polyurethane resin, and a polyolefin resin.

Examples of the polyester-based thermoplastic resin include aromatic carboxylic acids such as terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, and diphenyl-4-4'dicarboxylic acid.
At least one dicarboxylic acid selected from alicyclic carboxylic acids such as 1,4-cyclohexanedicarboxylic acid, aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dimer acid, and ester-forming derivatives thereof; And ethylene glycol, trimethylene glycol,
1,4-butanediol, tetramethylene glycol,
At least a diol component selected from aliphatic diols such as pentamethylene glycol and hexamethylene glycol, alicyclic diols such as 1,1-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, and ester-forming derivatives thereof. It is a block copolymer composed of one type. Further, polyethylene glycol having an average molecular weight of 300 to 5000 is used in these systems,
Polypropylene glycol, polytetramethylene glycol, a polyester polyether block copolymer obtained by copolymerizing at least one of polyalkylene diols composed of an ethylene oxide-propylene oxide copolymer, and a polylactone having an average molecular weight of 300 to 5000 may be used. A polyester ester block copolymer obtained by copolymerizing at least one of polyester diols may be used. In consideration of heat resistance and cost, terephthalic acid is preferable as the dicarboxylic acid, and polyethylene terephthalate composed of ethylene glycol is preferable as the diol component.

Examples of the polyamide thermoplastic resin include nylon 6, nylon 66, nylon 610, and nylon 61.
2, nylon 11, nylon 12, and copolymerized nylon thereof. Alternatively, these nylons are used as hard segments, and as soft segments, at least one of polyethylene glycol having an average molecular weight of about 300 to 5,000, polypropylene glycol, polytetramethylene glycol, and a polyalkylene diol comprising an ethylene oxide-propylene oxide copolymer. The constituent block copolymers may be used alone or in combination of two or more. Further, those obtained by blending or copolymerizing non-elastomeric components can also be used in the present invention.

As the polyurethane-based thermoplastic resin, (a) a number average molecular weight of 100 in the presence or absence of a usual solvent (dimethylformamide, dimethylacetamide, etc.)
A polyether and / or polyester having a hydroxyl group at the terminal of 0 to 6000 and a polyisocyanate having an organic diisocyanate as a main component are reacted with a prepolymer in which both ends are isocyanate groups. Polyurethane elastomer chain-extended with a polyamine to be described can be exemplified as a typical example. The average molecular weight of the polyesters and polyethers (a) is about 1
Polyalkylene diols such as polybutylene adipate copolymerized polyesters having a molecular weight of from 000 to 6000, preferably from 1300 to 5,000, and glycols composed of polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and ethylene oxide-propylene oxide copolymer are preferred. As the polyisocyanate, a conventionally known triisocyanate may be added in a small amount. As the polyamine (c), known diamines such as ethylenediamine and 1,2-propylenediamine are mainly used, and trace amounts of triamine and tetraamine may be used in combination as needed. These polyurethane-based thermoplastic resins may be used alone or in combination of two or more.

As the polyolefin-based thermoplastic resin,
Α- such as polyethylene, polypropylene and polybutene
In addition to olefin homopolymers, copolymers such as ethylene-propylene copolymer and ethylene-methyl acrylate copolymer may be used.

The cross-sectional shape of the antimicrobial fiber of the present invention is not particularly limited, but the antimicrobial fiber of the present invention becomes soft by a plasticizing effect when the phosphite compound is added in an amount of 2% by weight. Therefore, in the field of fiber fill where elastic recovery and bending hardness of a fiber aggregate such as futon cotton and hard cotton are required, a hollow cross section or an irregular cross section having a projection is preferable. In the case of a hollow section, the hollow ratio is
5% to 40% is preferred. If it is lower than 5%, the hollow section effect cannot be obtained, and if it exceeds 45%, the hollow section is crushed or ruptured in the working stage, and the hollow section effect cannot be obtained.

The cross-sectional shape of the antimicrobial fiber of the present invention may be a core-sheath type composite cross section. By adopting a core-sheath structure and adding an antibacterial agent only to the sheath component, it is possible to reduce the cost by reducing the amount of the antibacterial agent added. The weight ratio of the core-sheath component is as follows:
Sheath = 50: 50 to 90:10 is preferred. If the ratio of the sheath component is higher than 50% by weight, the amount of the antibacterial agent added to the sheath component increases, which is not preferable because the cost increases. On the other hand, if the content is lower than 10% by weight, the core component is exposed on the fiber surface due to the fluctuation of the melt viscosity of the thermoplastic resin or the eccentricity at the time of assembling the nozzle orifice. .

The fineness of the antibacterial fiber of the present invention is 0.5 to 2
0d is preferred. If the thickness is smaller than 0.5 d, spinning tends to be poor due to the plasticizer effect due to the addition of the antibacterial agent. If the thickness is larger than 20 d, the expected surface area of the fiber per unit weight is small, and the expected antibacterial properties cannot be obtained.

Although the production method of the present invention is not particularly limited, (1) a predetermined amount of a phosphite compound is mixed with a thermoplastic resin, then melt-kneaded, and re-melted using a re-pelletized resin. A method for forming a fiber, (2) after mixing a phosphite compound with a thermoplastic resin so as to have a high content of up to about 50% by weight and then melt-kneading the resulting pellet to form a master pellet, A method of forming fibers while mixing and melting with a thermoplastic resin and kneading, and (3) a method of forming fibers while melt-kneading after mixing a predetermined amount of a phosphite compound with a thermoplastic resin, and the like. .

In the method (1), a known amount of the thermoplastic resin (0.00.0 g) is mixed with a known blender such as a tumbler type mixer.
(0.05% by weight or more and 10% by weight or less) are added and mixed. At this time, when a polyester-based, polyamide-based, or polyurethane-based thermoplastic resin is preferably used, it is preferable to first heat it and dry it in a vacuum to remove water, because hydrolysis and viscosity change can be suppressed. No need). The phosphite compound is vacuum dried at room temperature to reduce the water content to 0.02% by weight.
It is preferable to set the following. The thermoplastic resin varies depending on the type, but it is 40 to 5 for polyester and polyurethane.
It is preferable that the mixture is vacuum-dried at 0 ° C. or 20 to 30 ° C. for a polyamide system to reduce the water content to 0.01% by weight or less, and mixed under a nitrogen purge. When the mixing time is about 5 to 30 minutes, blending is performed almost uniformly. Next, it is taken out into a container and supplied to an extruder from the container to be melt-kneaded. The extruder can be a single screw or twin or three screw
5 to 5 points higher than the melting point of the thermoplastic resin using a shaft screw
Melt extrude at 0 ° C higher temperature. If the difference from the melting point of the thermoplastic resin is less than 5 ° C., the melting is insufficient and uniform mixing cannot be performed. On the other hand, when the temperature exceeds 50 ° C., the thermal deterioration of the thermoplastic resin proceeds, and the mechanical properties of the antibacterial fiber are deteriorated. A preferred melt-kneading temperature is a temperature 10 to 30 ° C. higher than the melting point of the thermoplastic resin. The screw shape of the extruder is preferably a known kneading screw, more preferably a twin screw kneading with a vented extruder. In such a pelletizing step, there is a concern that foreign matter may be mixed, but a filter is preferably used in order to remove the foreign matter. Although the specifications of the filter vary depending on the intended product, 20 to 1200 meshes are used by lamination or a metal sintered filter is used in combination. The orifice diameter of the die at the outlet of the extruder is determined by the extruding amount of the extruder, but usually a die having a diameter of 1 to 3 mm is used. Since a general kneading extruder is not provided with a metering and feeding device, the extruding amount is set to a condition for obtaining pellets of a desired size from the extruding pressure, the screw rotation speed, and the take-up speed of a strand cutter. After the strand extruded from the die is cooled, the strand is cut into a desired length by a strand cutter to obtain a pellet. The obtained pellets are dried to reduce the water content to 0.01% by weight or less, and then supplied to a general melt extruder where they are heated and melted at a temperature 10 ° C. or more higher than the melting point of the thermoplastic resin. And discharged from a nozzle having a plurality of orifices. The discharged thermoplastic resin is
After being cooled just below the nozzle and applied with a fiber treatment agent, it is wound and then drawn, or is directly drawn and heat-treated and then wound, or is fiberized through a general spinning process. After bundling the wound yarns, crimping is performed and cut to a desired length to obtain crimped short fibers, and when cut to a desired length without crimping, non-crimped short fibers are obtained.

In a preferred embodiment of the present invention, the cross-sectional shape of the antibacterial fiber can be selected from a hollow cross section and / or an irregular cross section. To form a hollow cross section, an orifice in which the hole shape of the nozzle orifice is formed by connecting circular slits with one or three bridges is used. The hollow ratio of the orifice can be selected from 35 to 70%. If the hollow ratio of the nozzle orifice is less than 20%, the hollow ratio of the fiber cross section is less than 5%, and it is difficult to obtain a hollowing effect. If it exceeds 70%, the hollow ratio of the fiber cross section is too high, and This is not preferred because the probability of hollow rupture occurring in the post-processing step increases.
A preferable nozzle hollow ratio is 35 to 65%. The hollow ratio of the fiber cross section is preferably 5 to 40%. As a method of deforming the fiber cross section, a method of deforming the nozzle orifice is generally used. The irregular cross section can be selected according to a desired use such as a Y shape, a cross shape, and a star shape.

The method (2) is the same as the method (1) except that the amount of the phosphite compound added to the thermoplastic resin is adjusted so as to match the desired content required for the content at the time of fiber formation. In the same manner as above, the phosphite compound is added and mixed so as to have a high content, followed by melt-kneading to prepare a master pellet. The content of the phosphite compound in the master pellet is determined by the mixing ratio with the thermoplastic resin for dilution not containing the phosphite compound in the next spinning step. Usually, a master pellet of 5 to 50% by weight is mixed with a thermoplastic resin for dilution. The feeding method to the spinning machine is such that a predetermined amount of each of the master pellets and the thermoplastic resin for dilution is kneaded and supplied to the extruder to fiberize in the same manner as (1). The screw of the spinning machine is preferably of a kneading type. Particularly, a twin screw is preferable.

The method (3) includes a method in which a predetermined amount of a phosphite compound and a thermoplastic resin are once mixed, supplied to an extruder, melt-kneaded, and extruded from a nozzle orifice. There is a method in which a phosphate ester compound and a thermoplastic resin are separately metered and supplied to an extruder, directly mixed, melt-kneaded, and then extruded from a nozzle orifice. The fiber is formed in the same manner as in the method (1) below. In the method (3), the screw of the extruder of the spinning machine is preferably of a kneading type. Particularly, a twin screw is preferable. Further, a spinning machine incorporating a kneading mechanism (for example, a static mixer or the like) other than the screw of the extruder before spinning the yarn is preferable.

As a preferred embodiment of the antibacterial fiber of the present invention, a thermoplastic resin containing a phosphite ester compound in a sheath component having a core-in-sheath structure using a composite spinning machine is used. The form used can be selected. The weight ratio of the core-sheath component is preferably core: sheath = 50: 50 to 95: 5. If the sheath component ratio is higher than 50% by weight, the content of the antibacterial agent in the sheath component is increased, which results in an increase in cost due to the use of complicated spinning equipment, which is not preferable. On the other hand, if the content is lower than 5% by weight, the core component is exposed on the fiber surface due to the fluctuation of the melt viscosity of the thermoplastic resin or the eccentricity during the assembly of the nozzle orifice. As the shape of the nozzle orifice, a hollow cross section and a modified cross section can be selected in addition to the round cross section. By increasing the fiber surface area per unit weight, the antibacterial property can be further improved at a low content.

[0035]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. The evaluation in the examples was performed by the following method. (1) Antibacterial property of antibacterial composition The procedure was based on the manual for quantitatively testing the antibacterial properties of textile products, which was established by the Evaluation Committee for New Functions of Textile Products. Specifically, 0.4 g of a sample of the following test bacteria (1 ± 0.3 × 105 cells / ml) is uniformly inoculated into the sterilized 1/20 concentration nutrient broth, and cultured at 37 ° C. for 18 hours. After completion of the culture, the test bacteria were washed out, and a pour plate agar medium was prepared with the solution,
The cells are cultured at 37 ° C for 24-48 hours, and the number of viable cells is measured. As for the unprocessed product, the test bacteria were washed out immediately after inoculation, and a pour plate agar medium was prepared using the solution, and the mixture was incubated at 37 ° C for 24 hours.
By incubating for ~ 48 hours, the number of viable cells inoculated is measured. The antibacterial activity is evaluated by a bacteriostatic activity value according to the following formula.
The higher the bacteriostatic activity value, the better the antibacterial property. In addition,
As a test bacterium, Staphylococcus
ccus aureus ATCC 6538P). Bacteriostatic activity value = Log (B)-Log (C) However, test establishment conditions: Log (B)-Log (A)>
1.5 must be satisfied. A: Average value of the number of bacteria collected immediately after inoculation of the raw product B: Average value of the number of bacteria collected and cultured for 18 hours of the raw product C: Average value of the number of bacteria collected and cultured for 18 hours of the processed product

(2) Washing method The washing method manual was established by the Textile Product New Function Evaluation Council. That is, using a home electric washing machine specified in the washing method 103 of JIS L0217,
Dissolve 40 liters of JAFET standard detergent (manufactured by the Japan Textile Products Association) in 30 liters of water at ℃ to make a washing liquid.
A 1 kg sample is put into the washing liquid. Washing for 5 minutes, rinsing for 2 minutes, rinsing for 2 minutes, rinsing for 2 minutes, and rinsing for 1 minute were performed once, and 50 washes were performed.

Examples 1 to 9 and Comparative Examples 1 and 2 In Examples and Comparative Examples, the thermoplastic resins shown in Table 1 were used.

[0038]

[Table 1]

Next, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite (phosphite ester compound) previously dried under vacuum at 30 ° C. for 48 hours was added to the thermoplastic resin pellets shown in Table 1. The following BM
PP) or bis (2,6-di-tert-butylphenyl) pentaerythritol diphosphite (hereinafter referred to as BH
PP) (abbreviated as PP), dry-blended with a rotary blender, and melt-kneaded in a melt extruder at a temperature 25 to 35 ° C. higher than the melting point of the thermoplastic resin. The mixture was discharged from a die having a hole diameter of 1 mm, cooled and cut to obtain pellets. Next, it was vacuum dried at 50 ° C. for 48 hours, and the bleed-out state of the antibacterial functional agent was confirmed. Table 2 shows the kneading formulation, the clogging of the filter, and the state of bleed-out on the polymer surface after drying.
In addition, the filter immediately before the dice used the laminated product of stainless steel 50 mesh / 150 mesh / 20 mesh.

[0040]

[Table 2]

The obtained phosphite compound-added thermoplastic resin composition is further melt-extruded by a melt extruder at a temperature 20 to 40 ° C. higher than the melting point of the thermoplastic resin. A multifilament is discharged from a nozzle having a plurality of orifices. After the discharged multifilament is gradually cooled,
It is wound up. The wound undrawn yarn was drawn and heat-set so as to have a fineness of 2 denier, and then wound as a finished yarn. Table 3 shows the antibacterial properties of the obtained antibacterial fibers.

[0042]

[Table 3]

It can be seen from Tables 1 and 2 that Examples 1 to 10 have excellent antibacterial properties and durability and also have good handling properties of the resin containing the antibacterial agent. Comparative Example 1 does not cause bleed-out of the antibacterial agent, but is not preferable because of poor antibacterial properties. In Comparative Example 2, although the antibacterial property and the durability are excellent, the bleed-out of the additive at the time of dry blending of the resin is remarkably unfavorable. Further, those obtained in the examples had mechanical properties having no practical problem.

Examples 11 to 14, Comparative Example 3 An antibacterial fiber was obtained in the same manner as in Example 1 except that the shape of the nozzle orifice hole was hollow and a modified cross section, and the fibers were bundled together. After crimping with a crimping device,
Crimped short fibers (raw cotton) were obtained by cutting with a rotor-type cutter.

[0045]

[Table 4]

Examples 11 to 14 are high in bulkiness and lightness, and excellent in antibacterial properties. In Comparative Example 3, although the cross-sectional shape of the fiber was a hollow cross-section, the hollow fiber ratio was 45% or more, so that the hollow was crushed and the bulkiness was unexpectedly low, and further hollow rupture occurred in the post-processing step. The effect of the cross section cannot be obtained.

Examples 15 to 16 and Comparative Example 4 Using a multi-component spinning machine, the sheath component was the thermoplastic resin used in Example 1, and the core component was PET without phosphite.
A core-sheath type composite fiber was spun out, and stretched and heat-set in the same manner as in Example 1 to obtain an antibacterial fiber.

[0048]

[Table 5]

In Examples 15 and 16, the cost can be reduced without reducing the antibacterial property by using the core-sheath structure. In Comparative Example 4, since the core component ratio was too high, the core component was exposed on the surface of the fiber, so that the antibacterial property was poor.

Examples 17-18, Comparative Examples 5-6 Antibacterial fibers were obtained in the same manner as in Example 1 except that the hole diameter of the nozzle orifice and the single hole discharge amount were changed depending on the fineness. The fiber sections were all round sections.

[0051]

[Table 6]

Examples 17 and 18 have good spinnability and antibacterial properties. In Comparative Example 5, antibacterial fibers could not be obtained due to poor spinnability. In Comparative Example 6,
Although the spinnability was reasonable, the antibacterial properties were not satisfactory because the surface area per unit weight was small.

[0053]

According to the present invention, a phosphite compound, which exhibits little antibacterial properties by itself, is melted and kneaded with a thermoplastic resin to form a fiber, which is economically excellent in antibacterial properties and durability. Antibacterial fibers can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D01F 8/04 D01F 8/04 Z 8/14 8/14 Z // C08K 5/527 C08K 5/527 C08L 101/00 C08L 101/00 (72) Inventor Kenji Yoshino 2-1-1 Katata, Otsu-shi, Shiga F-Term in Toyobo Co., Ltd. Research Laboratory 4J002 BB031 BB071 BB121 BB151 BB171 CF031 CF041 CF051 CF061 CF081 CF101 CF171 CK031 CK041 CL011 CL031 CL071 EW066 EW086 FA041 FA051 FD186 GK01 4L035 BB31 EE11 HH05 HH10 JJ25 KK05 4L041 AA07 BA02 BA05 BA21 BC10 CA06 CA21 CA33 CA37 CB19 CB28 DD01 DD14 DD21

Claims (4)

[Claims] 1. A phosphite compound represented by the following general formula (I) is melt-kneaded at a content of 0.005 to 10% by weight with respect to a thermoplastic resin,
And an antibacterial fiber obtained by spinning. Embedded image (In the above formula, R ¹ represents a branched alkyl group having 4 to 12 carbon atoms, a cycloar group or an arylalkyl group;
R ² represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group or an aryl ants kill group, R ³
Is a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, a cycloalkyl group, an arylalkyl group, or -R ⁶ COOR ⁷
R ⁶ represents an alkylene group having 1 to 6 carbon atoms, R ⁷ represents an alkyl group or an aryl group having 1 to 18 carbon atoms, and R ⁴ and R ⁵ each independently represent 1 ~
An alkyl group of 8, an alkyl group having 1 to 4 carbon atoms substituted with a hydroxy group, or a group having the following structure (II) in which R ⁴ and R ⁵ are combined. ) (In the above formula, R1, R2 and R3 are the same as in the general formula (I).) 2. The antibacterial fiber according to claim 1, wherein the phosphite compound of the general formula (I) is the following compound (A). Embedded image 3. The antibacterial fiber according to claim 1, wherein the phosphite compound of the general formula (I) is the following compound (B). Embedded image 4. A heat treatment wherein the cross section of the fiber has a core-in-sheath structure, and only the sheath component contains 0.005 to 10% by weight of at least one phosphite compound represented by the general formula (I). It is made of a plastic resin, and the weight ratio of the core and the sheath is 50:
The antibacterial fiber according to any one of claims 1 to 3, which is in a range of 50 to 90:10.