JP2000045179A - Antimicrobial fiber and its fibrous structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an antimicrobial fiber and its fibrous structure excellent in resistance to washing by carrying out a graft polymerization of an antimicrobial vinyl monomer or the above antimicrobial vinyl monomer and a hydrophilic vinyl monomer with a cellulosic fiber. SOLUTION: This antimicrobial fiber is obtained by applying a prescribed amount of an aqueous solution containing an antimicrobial vinyl monomer such as a phosphonium salt-based compound, e.g. tributyl(4-vinylbenzyl) phosphonium chloride and/or a quaternary ammonium salt-based compound, e.g. trimethyl(2-acryloyloxyethyl)ammonium chloride or the above antimicrobial vinyl monomer and a hydrophilic vinyl monomer, e.g. acrylic acid and further a polymerization initiator to a cellulosic fiber such as cotton, then heat-treating the resultant cellulosic fiber at 80-200 deg.C, polymerizing the above antimicrobial vinyl monomer and carrying out a graft polymerization of at least >=0.1 wt.% of the antimicrobial vinyl monomer therewith.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antibacterial fiber excellent in durability against repeated washing and a fibrous structure. In detail, antibacterial vinyl monomer, or antibacterial fiber excellent in durability to repeated washing containing a graft copolymer obtained by graft copolymerization of an antibacterial vinyl monomer and a hydrophilic vinyl monomer in a cellulose fiber, and The present invention relates to a fiber structure.

[0002]

2. Description of the Related Art Unpleasant odors may be generated from textile products by wearing the textile products. It is known that this odor is one of the causes due to organic acids and amines secreted by bacteria grown on the fiber using sweat, skin stains and the like as a nutrient source. Furthermore, in hospitals and other medical institutions and food-related facilities, there is a concern that the surrounding environment will be contaminated by the growth of pathogenic bacteria attached to the fibers. In recent years, various antibacterial fibers for suppressing bacterial growth have been studied.

As a method for imparting antibacterial properties to fibers, a method using a metal compound or metal ion is disclosed in Japanese Patent Application Laid-Open No. 54-160.
No. 900, JP-A-55-137210 and the like. Further, a method using an organosilicone antibacterial agent having a quaternary ammonium base is disclosed in JP-A-57-518.
No. 74, JP-A-59-71480, JP-A-59-86
632 and the like. In addition, methods of kneading zeolite particles having antibacterial properties into thermoplastic resin fibers and methods of using various antibacterial agents such as imidazole antibacterial agents, trichlorocarbanilide antibacterial agents, and chitosan are disclosed.

[0004] One of the problems in imparting antibacterial properties to fibers is to impart antibacterial properties having durability (hereinafter, abbreviated as washing durability) to repeated washing. As a method for overcoming this problem, a method of kneading an antibacterial compound into a fiber-forming polymer is disclosed in JP-A-5-496.
82 and JP-A-5-339811. However, these are limited to regenerated cellulosic fibers and cannot be applied to natural cellulosic fibers such as cotton and hemp. As a method for imparting washing durability to natural cellulose-based fibers, a method using the above-mentioned organosilicone-based antibacterial agent having a quaternary ammonium base is known. That is, by covalently bonding the hydroxyl group of the cellulosic fiber and the methoxy group of the antibacterial agent, antibacterial properties with washing durability can be obtained. However, in this method, water repellency is simultaneously imparted to the fibers by the silicone, and the obtained washing durability is also insufficient.

[0005]

Accordingly, it is an object of the present invention to provide a fiber and a fibrous structure having antibacterial properties which are durable against repeated washing.

[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, have found that a fiber and a fibrous structure having washing durability and antibacterial properties are obtained. Was completed.

That is, the present invention provides (1) an antibacterial fiber comprising a graft copolymer obtained by graft-copolymerizing an antibacterial vinyl monomer to a cellulosic fiber;
(2) an antibacterial fiber, characterized by containing a graft copolymer obtained by graft copolymerizing an antibacterial vinyl monomer and a hydrophilic vinyl monomer into a cellulosic fiber;
(3) The antibacterial fiber of (1) or (2), wherein the antibacterial vinyl monomer is a phosphonium salt compound and / or a quaternary ammonium salt compound.
(4) The antibacterial fiber according to (1) to (3), wherein the antibacterial vinyl monomer is polymerized at least 0.1% by weight or more with respect to the cellulosic fiber and contained.
And (5) a fibrous structure containing the antibacterial fiber of (1) to (4).

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. Natural fibers, regenerated fibers, semi-synthetic fibers, or the like may be used as the cellulosic fibers used in the present invention. The natural fibers include, for example, cotton and hemp, the regenerated fibers include, for example, rayon, polynosic, lyocell, cupra, and the like, and the semi-synthetic fibers include, for example, acetate.

The cellulosic fibers may have been subjected to desizing, refining, bleaching, mercerizing, liquid ammonia treatment, etc., as a general under exposure treatment.

[0010] In the fiber and fiber structure of the present invention,
Materials other than cellulosic fibers can be mixed.
The material other than the cellulosic fiber is not particularly limited, and examples thereof include polyester, polypropylene, polyethylene, polyamide, acrylic, polyurethane, polyvinyl chloride, vinylon, wool, and silk.

The antibacterial vinyl monomer used in the present invention is a monomer having at least one vinyl group as a polymerization site and having antibacterial properties. The functional group imparting antibacterial properties is not particularly limited, and examples thereof include a quaternary phosphonium group, a quaternary ammonium group, a biguanide group, and a pyridinium group.

The antibacterial vinyl monomer is not particularly restricted but includes, for example, phosphonium salt compounds, quaternary ammonium salt compounds, biguanide compounds, pyridinium salt compounds and the like.

The phosphonium salt compound used in the present invention is represented by the formula (1)

[0014]

Embedded image

(Where R¹Is H or low C 1-6
A lower alkyl group represented by R^Two, R^ThreeAnd R ^FourAre the same or different
Each of which may have 1 to 20 carbon atoms
X represents a halogen or a residue of an inorganic acid or an organic acid;
Represents 1,4-phenylene or —C (＝ O) O—, and
And n are integers of 0 to 4 (provided that A is -C (= O) O-
In this case, n = 0 is excluded. ). )
What is it?

The phosphonium salt compounds include, for example, trimethyl (4-vinylbenzyl) phosphonium chloride, tributyl (4-vinylbenzyl) phosphonium chloride, trihexyl (4-vinylbenzyl) phosphonium chloride, trioctyl (4-vinylbenzyl) phosphonium Chloride, dimethylbutyl (4-vinylbenzyl) phosphonium chloride, dimethyloctyl (4-vinylbenzyl) phosphonium chloride,
Trimethyl (2-methacryloyloxyethyl) phosphonium chloride, tributyl (2-methacryloyloxyethyl) phosphonium chloride, trihexyl (2-methacryloyloxyethyl) phosphonium chloride, trioctyl (2-methacryloyloxyethyl) phosphonium chloride, dimethylbutyl (2-methacryloyl) Oxyethyl) phosphonium chloride,
Dimethyl octyl (2-methacryloyloxyethyl)
Phosphonium chloride and the like are preferable, and tributyl (4-vinylbenzyl) phosphonium chloride and tributyl (2-methacryloyloxyethyl) phosphonium chloride are preferable.

The quaternary ammonium salt compound used in the present invention is represented by the formula (2)

[0018]

Embedded image

(Wherein R¹Is H or low C 1-6
A lower alkyl group represented by R^Two, R^ThreeAnd R ^FourAre the same or different
Each of which may have 1 to 20 carbon atoms
X represents a halogen or a residue of an inorganic acid or an organic acid;
Represents 1,4-phenylene or —C (＝ O) O—, and
And n are integers of 0 to 4 (provided that B is -C (= O) O-
In this case, n = 0 is excluded. ). )
What is it?

The quaternary ammonium salt compounds include, for example, trimethyl (4-vinylbenzyl) ammonium chloride, dimethyloctyl (4-vinylbenzyl) ammonium chloride, dimethyldecyl (4-vinylbenzyl) ammonium chloride, dimethyldodecyl (4
-Vinylbenzyl) ammonium chloride, trimethyl (2-methacryloyloxyethyl) ammonium chloride, dimethyloctyl (2-methacryloyloxyethyl) ammonium chloride, dimethyldecyl (2-methacryloyloxyethyl) ammonium chloride, dimethyldodecyl (2-methacryloyloxyethyl) ) Ammonium chloride, trimethyl (2-acryloyloxyethyl) ammonium chloride, dimethyloctyl (2-acryloyloxyethyl) ammonium chloride, dimethyldecyl (2-acryloyloxyethyl) ammonium chloride, dimethyldodecyl (2-acryloyloxyethyl) ammonium chloride And the like, preferably trimethyl (2
-Acryloyloxyethyl) ammonium chloride, trimethyl (2-methacryloyloxyethyl) ammonium chloride and the like.

With respect to formulas (1) and (2), the lower alkyl group having 1 to 6 carbon atoms in R ¹ may be linear or branched, for example, methyl, ethyl, propyl, isopropyl, butyl, tert- Examples include butyl, pentyl, hexyl and the like, and preferably methyl.

R ¹ , R ³ and R ^{4 have} 1 to 1 carbon atoms.
20 alkyl groups may be linear or branched;
It is preferably a straight-chain alkyl group having 1 to 12 carbon atoms, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl and dodecyl.

As the halogen for X, chlorine or bromine is preferably used.

Examples of the residue of an inorganic acid or an organic acid include a sulfonic acid group, a sulfuric acid group, a phosphoric acid group and a carboxylic acid group.

The hydrophilic vinyl monomer used in the present invention is a monomer having at least one vinyl group as a polymerization site and having a hydrophilic functional group. In the present invention, the hydrophilic vinyl monomer means one having a higher water absorption than the original cellulosic fiber when copolymerized with the cellulosic fiber.

As the hydrophilic functional group, a hydroxyl group, an amino group,
Sulfonic acid group, oxyethylene group (—CH ₂ CH ₂ O
-) And a carboxyl group.

The hydrophilic vinyl monomer is not particularly limited. For example, various monomers such as acrylic acid, methacrylic acid, acrylamide, N-methylolacrylamide, vinylsulfonic acid and styrenesulfonic acid, and methoxy obtained by adding ethylene oxide to the above monomer Examples include polyethylene glycol acrylate and methoxy polyethylene glycol methacrylate.

In the antibacterial fiber of the present invention, it is preferable that the antibacterial vinyl monomer is polymerized and contained at least 0.1% by weight based on the cellulosic fiber.
When the content is less than 0.1% by weight, the antibacterial property imparted to the product becomes insufficient. On the other hand, when the content is 30% by weight or more, the characteristics of the cellulosic fiber are lost, which is not preferable.

In the present invention, the fibrous structure includes raw cotton,
Includes yarn, woven, knitted, non-woven, sewn products, and the like.

The method of graft copolymerizing the antibacterial vinyl monomer or the antibacterial vinyl monomer and the hydrophilic vinyl monomer with the cellulosic fiber can be carried out by a conventionally known method. Further, when the antibacterial vinyl monomer is copolymerized with the cellulosic fiber, the hydrophilicity of the fiber is reduced to some extent. When a hydrophilic vinyl monomer is graft-copolymerized with a cellulosic fiber together with an antibacterial vinyl monomer, the hydrophilicity of the fiber can be increased.

The initiation of the graft copolymerization is preferably carried out by, for example, a chemical method using a polymerization initiator. A method of forming free radicals on cellulose molecules photochemically or radiochemically to initiate polymerization (hereinafter referred to as photopolymerization). Or abbreviated as radiochemical method).

As a method using a polymerization initiator, for example, an immersion method in which a cellulose fiber is immersed for a predetermined time in an antibacterial vinyl monomer or an aqueous solution containing an antibacterial vinyl monomer and a hydrophilic vinyl monomer and a polymerization initiator (hereinafter, referred to as an immersion method).
Abbreviated as immersion method. ), And in order to efficiently carry out the cellulosic fiber in the aqueous solution, preferably 40 to 90.
C., preferably for 10 minutes to 5 hours to carry out polymerization.

As a method of using a polymerization initiator, a predetermined amount of an antibacterial vinyl monomer or an aqueous solution containing an antibacterial vinyl monomer and a hydrophilic vinyl monomer and a polymerization initiator is applied to a cellulosic fiber and then subjected to a wet heat treatment. A method of performing dry heat treatment (abbreviated as a heat treatment method) is also included. The “method of applying a fixed amount” is not particularly limited, and examples thereof include a padding method, a spray method, and a coating method. In order to carry out the polymerization efficiently after applying a certain amount of the aqueous solution to the fiber, the polymerization can be carried out by heat treatment at preferably 80 to 200 ° C., preferably for 20 seconds to 5 minutes.

As the polymerization initiator, those generally used in radical polymerization may be used.
Examples include peroxides such as t-butyl and benzoyl peroxide, azo compounds such as azobisisobutyronitrile, and redox initiators such as ammonium persulfate, potassium persulfate, and cerium salt catalysts.

The concentration of the antibacterial vinyl monomer in the processing solution in the graft copolymerization using the polymerization initiator is not particularly limited, and is 0.1 to 300% based on the cellulosic fiber.
% Is preferable. When the amount is less than 0.1% by weight, the antibacterial property of the produced product becomes insufficient, and when it exceeds 300% by weight, the cost increases. When the phosphonium salt-based compound and the quaternary ammonium salt-based compound are used as the antibacterial vinyl monomer, the concentration of the antibacterial vinyl monomer is determined by adding the amount of the phosphonium salt-based compound and the amount of the quaternary ammonium salt-based compound. 3 shows the concentration based on the weight of the cellulosic fiber.

[0036] The concentration of the hydrophilic vinyl monomer in the processing solution in the graft copolymerization using the polymerization initiator is not particularly limited, and is 0.1 to 300 based on the cellulosic fiber.
% Is preferred, and if it is less than 0.1% by weight, the resulting product has insufficient hydrophilicity.

The concentration of the polymerization initiator in the graft copolymerization using the polymerization initiator is not particularly limited, and from the viewpoint of efficiency, the antibacterial vinyl monomer contained in the polymerization system, or the antibacterial vinyl monomer and the hydrophilic vinyl monomer are used. 1 ~
40% by weight is preferred.

In the photochemical or radiochemical method, it is possible to irradiate only the cellulosic fiber with light or radiation and then contact the vinyl monomer, or to irradiate in the coexistence of the cellulosic fiber and the vinyl monomer to generate radicals. Good.

The concentration of the antibacterial vinyl monomer in the processing solution in the photochemical or radiochemical method is not particularly limited, and is preferably from 0.1 to 300% by weight, and preferably less than 0.1% by weight, based on the cellulosic fiber. When the content becomes too high, the antibacterial property of the product becomes insufficient, and when it exceeds 300% by weight, the cost becomes high. When the phosphonium salt-based compound and the quaternary ammonium salt-based compound are used as the antibacterial vinyl monomer, the concentration of the antibacterial vinyl monomer is determined by adding the amount of the phosphonium salt-based compound and the amount of the quaternary ammonium salt-based compound. 3 shows the concentration based on the weight of the cellulosic fiber.

The concentration of the hydrophilic vinyl monomer in the processing solution in the photo- or radiation-chemical method is not particularly limited, and is preferably 0.1 to 300% by weight, more preferably less than 0.1% by weight, based on the cellulosic fiber. The resulting product becomes insufficiently hydrophilic.

The light and radiation used in the light or radiochemical method are preferably, for example, ultraviolet rays, γ-rays and electron beams.

The polymerization time in the photochemical or radiochemical method varies depending on the irradiation dose, and is usually preferably from 1 second to 24 hours.

The graft polymerization can be performed on any fibrous structure of cellulosic fibers. For example,
After the graft polymerization is performed on the raw cotton, a yarn or a cloth may be formed, or the graft polymerization may be performed after forming the cloth. Similarly, in the case of mixing fibers other than the cellulosic fibers, antibacterial properties may be imparted after mixing other materials with the cellulosic fibers before polymerization, and the antibacterial fibers or fibers of the present invention after polymerization. A product combining a structure and another material may be created.

The antibacterial fibrous structure obtained by the treatment method of the present invention may be subjected to conventionally known finishing processes such as shrink-proofing process, wrinkle-proofing process, wash and wear process, hydrophilic process, water absorbing process, and flexible process. Water repellent processing, deodorizing processing, mold prevention processing, flame prevention processing, flame retarding processing, and the like may be performed.

[0045]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to these examples. The evaluation methods used in the examples and comparative examples are as follows.

(1) Antibacterial activity In accordance with the Manual for Quantitative Antibacterial Testing of Textile Products, established by the Evaluation Committee for New Functions of Textile Products, Staphylococcus aureus was used as a test bacterium.
ureus ATCC 6538P) was used. 0.4 g of a test bacterial suspension containing 1 ± 0.3 × 10 ⁵ cells / ml of a test bacterium was uniformly inoculated into 0.4 g of a sample in a sterilized 1/20 concentration nutrient broth. 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, and the mixture was cultured at 37 ° C for 24 to 48 hours.
After culturing for a time, the number of viable bacteria was measured. In addition, about a raw cloth, the test bacteria were washed out immediately after inoculation, a pour plate agar medium was prepared from the solution, and cultured at 37 ° C. for 24-48 hours to measure the number of inoculated viable bacteria. The antibacterial activity was evaluated by a bacteriostatic activity value according to the following formula. The higher the bacteriostatic activity value, the better the antibacterial property.

Bacteriostatic activity value = LogB-LogC, provided that the test was completed (LogB-LogA)> 1.5
Meet. (Where A is the average number of bacteria collected immediately after inoculation of the raw cloth, B is the average number of bacteria recovered after 18 hours of cultivation of the raw cloth, and C is the 18 hour culture of the processed cloth. This represents the average value of the number of bacteria collected later.)

(2) Water Absorbency Based on JIS L-1096 (dropping method).

(3) Weight increase rate Calculated from the following equation. (X−Y) / Y × 100 (where X represents the absolute dry weight of the sample after the graft copolymerization, and Y represents the absolute dry weight of the sample before the graft copolymerization.)

(4) Washing method The washing method manual was established by the Council for Evaluation of New Functions of Textile Products. The washing machine used was a home electric washing machine specified in the washing method 103 of JIS L0217. The washing liquid was prepared by dissolving 40 ml of JAFET standard detergent (produced by the Evaluation Committee for New Functions of Textile Products) in 30 l of water at 40 ° C. The solution was used. A sample of 1 kg was put in the washing liquid, and washing was performed for 5 minutes, washing was performed for 2 minutes, washing was performed for 2 minutes, washing was performed for 2 minutes, and washing was performed 50 times as one washing operation.

Example 1 Cotton 10 after refining, bleaching and mercerizing
0% plain woven fabric (yarn use: warp 50th × weft 50th, weave density: warp 144 / inch × weft 81 / inch, basis weight:
102 g / m ² ) and 2% by weight of tributyl (4%).
-Vinylbenzyl) phosphonium chloride and 0.5 ml by weight of an aqueous solution containing 0.5% by weight of diammonium cerium (IV) nitrate, and treated at 60 ° C. for 120 minutes. After the treatment, a washing treatment was performed with hot water at 90 ° C. The obtained fabric showed high antibacterial properties even after 50 times of washing as shown in Table 1.

Example 2 As a processing solution, 2% by weight of tributyl (2-methacryloyloxyethyl) phosphonium chloride and 0.5%
The procedure was performed in the same manner as in Example 1 except that 100 ml of an aqueous solution containing cerium (IV) diammonium nitrate by weight was used. The obtained fabric was washed 50 times as shown in Table 1.
It showed high antibacterial properties after the test.

Example 3 A processing liquid was used except that 100 ml of an aqueous solution containing 5% by weight of trimethyl (2-acryloyloxyethyl) ammonium chloride and 0.5% by weight of diammonium cerium (IV) nitrate was used. It carried out like Example 1. The obtained fabric showed high antibacterial properties even after 50 times of washing as shown in Table 1.

Example 4 As a processing solution, 100 ml of an aqueous solution containing 2% by weight of tributyl (4-vinylbenzyl) phosphonium chloride, 2% by weight of acrylic acid, and 0.5% by weight of diammonium cerium (IV) nitrate was used. The procedure was the same as in Example 1, except for the fact that As shown in Table 1, the obtained fabric exhibited high antibacterial properties even after 50 times of washing, and also exhibited excellent water absorption.

Example 5 Cotton 10 subjected to refining, bleaching and mercerizing
0% plain woven fabric (yarn use: warp 50th × weft 50th, weave density: warp 144 / inch × weft 81 / inch, basis weight:
102 g / m ² ) was padded to an aqueous solution containing 2% by weight tributyl (4-vinylbenzyl) phosphonium chloride, 2% by weight acrylic acid, and 0.5% by weight cerium (IV) diammonium nitrate, and squeezed with a mangle. After squeezing at a rate of 65%, a dry heat treatment was performed at 150 ° C. for 2 minutes, and a washing treatment was performed with hot water at 90 ° C. As shown in Table 1, the obtained fabric exhibited high antibacterial properties even after 50 times of washing, and also exhibited excellent water absorption.

Comparative Example 1 The procedure of Example 1 was repeated except that diammonium cerium (IV) nitrate as a polymerization initiator was not used as a processing solution. As shown in Table 1, the obtained fabric hardly showed an increase in polymerization due to graft copolymerization of monomers, and did not show sufficient antibacterial properties.

Comparative Example 2 The same procedure as in Example 1 was carried out except that tributyl (4-vinylbenzyl) phosphonium chloride, which is an antibacterial vinyl monomer, was used as a processing solution in an amount of 0.05% by weight. As shown in Table 1, the obtained fabric hardly showed an increase in polymerization due to graft copolymerization of monomers, and did not show sufficient antibacterial properties.

[0058]

[Table 1]

[0059]

Industrial Applicability According to the present invention, a fiber having excellent antibacterial properties that can withstand repeated washing can be obtained, and an antibacterial fiber structure widely applicable to general clothing applications can be provided.

Claims (5)

[Claims] 1. An antimicrobial fiber comprising a graft copolymer obtained by graft copolymerizing an antimicrobial vinyl monomer to a cellulosic fiber. 2. An antibacterial fiber comprising a cellulosic fiber containing a graft copolymer obtained by graft copolymerizing an antibacterial vinyl monomer and a hydrophilic vinyl monomer. 3. The antibacterial fiber according to claim 1, wherein the antibacterial vinyl monomer is a phosphonium salt compound and / or a quaternary ammonium salt compound. 4. The method according to claim 1, wherein the antibacterial vinyl monomer is polymerized at least 0.1% by weight with respect to the cellulosic fiber.
The antibacterial fiber according to any one of the above. 5. A fibrous structure containing the antibacterial fiber according to any one of claims 1 to 4.