JP7102555B2 - Polyurethane elastic fiber and fabric containing it - Google Patents

Description

The present invention relates to polyurethane elastic fibers and fabrics containing them. More specifically, the present invention relates to polyurethane elastic fibers containing an inorganic deodorant and fabrics containing the same.

Polyurethane elastic fibers have high elongation and excellent elastic properties. Taking advantage of its elastic properties, it is used in various applications that require elasticity such as innerwear, socks, sportswear, and sanitary materials such as diapers. In these applications, in recent years, there has been an increasing demand for fabrics having deodorizing performance, particularly the deodorizing performance of ammonia odor.
In the following Patent Document 1, for a stretchable fabric containing polyurethane elastic fibers, a composite coating layer having an inner layer made of a hydrophilic resin and an outer layer made of a binder resin containing a composite of silicon dioxide and zinc oxide is treated by post-processing. A method for obtaining a deodorant cloth has been reported. However, although there are some technological advances, such a post-processing method has the problem that the deodorant on the surface of the fabric falls off due to washing, etc., and the deodorizing performance deteriorates, and it is used in post-processing. There is a problem that the texture of the fabric is deteriorated by the binder, and these problems have not been sufficiently solved yet. In addition, there is a problem that a manufacturing process called "post-processing" must be added in the manufacturing of the fabric, which imposes a heavy burden on both cost and work man-hours.

The following Patent Documents 2 and 3 report polyurethane elastic fibers containing an inorganic deodorant such as zinc or zirconium. By using these polyurethane elastic fibers, it is not necessary to perform the above-mentioned "post-processing", so it is possible to obtain a deodorant fabric with a good texture without burdening costs and work manpower, but the inorganic deodorant is polyurethane. Aggregates in the undiluted spinning solution and causes filter clogging in the manufacturing process, and aggregates of inorganic deodorant are generated in the yarn, causing yarn breakage during product use and wear of knitting needles during knitting. There is a problem that continuous production and use of yarn are difficult.

In the following Patent Document 4, a wet dispersant is added in order to suppress aggregation of the inorganic deodorant in the production of polyurethane elastic fiber containing an inorganic deodorant selected from zirconium phosphate, zinc oxide and the like. It has been reported to do. However, there are problems that the cost increases due to the use of the wet dispersant, the man-hour load increases, and the deodorizing performance is impaired by the wet dispersant.
As described above, various techniques have been studied for producing a fabric having deodorizing performance, but a sufficient solution has not been reached from the viewpoint of the texture of the fabric, the productivity of polyurethane elastic fibers, and needle wear.

JP-A-2015-343666 Japanese Unexamined Patent Publication No. 2002-105757 Japanese Unexamined Patent Publication No. 2006-288453 International Publication No. 2018/128436

In view of the above-mentioned problems of the prior art, an object to be solved by the present invention is to provide a polyurethane elastic fiber that can eliminate the wear of the knitting needle during knitting and further exhibits high deodorizing performance. ..

As a result of diligent studies and experiments in order to solve the above-mentioned problems, the inventor of the present application can solve the above-mentioned problems by setting the reduced viscosity of the polyurethane elastic fiber containing an inorganic deodorant within a specific range. We have found what we can do and have completed the present invention.
That is, the present invention is as follows.

[1] A polyurethane elastic fiber having a reduced viscosity of 1.40 or more and 3.80 or less and containing an inorganic deodorant, and having a polystyrene-equivalent weight average molecular weight (Mw) and a number measured by GPC. A polyurethane elastic fiber having a molecular weight distribution (Mw / Mn) represented by a ratio of average molecular weight (Mn) of 1.50 or more and 2.10 or less .
[2] The polyurethane elastic fiber according to the above [1], wherein the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is 160,000 or more and 400,000 or less.
[ 3 ] The inorganic deodorant is a metal oxide or composite metal oxide or metal phosphate containing at least one metal atom selected from the group consisting of Ti, Zr, Ag, Zn, Al, and Si. The polyurethane elastic fiber according to the above [1] or [2] , which contains at least one of the salts.
[ 4 ] The inorganic deodorant is either a metal phosphate containing Ti, Zr or Al, a composite metal oxide composed of silicon dioxide and zinc oxide, or a composite metal oxide composed of silicon dioxide and zirconium oxide. The polyurethane elastic fiber according to any one of [1] to [ 3 ] above, which comprises one or more of them.
[ 5 ] Any of the above [1] to [ 4 ], which does not contain particles of 6 μm or more in the particle size measurement by a wet particle size distribution meter in DMAc of a solution of the polyurethane elastic fiber dissolved in dimethylacetamide (DMAc). Polyurethane elastic fiber described in Crab.
[ 6 ] The polyurethane elastic fiber according to any one of [1] to [ 5 ] above, wherein the content of the inorganic deodorant is 1 to 10 parts by weight with respect to 100 parts by weight of the polyurethane polymer.
[ 7 ] Any of the above [1] to [ 6 ], which further contains 0.01 to 0.50 parts by weight of a magnesium salt of a long-chain fatty acid having 10 to 20 carbon atoms with respect to 100 parts by weight of the polyurethane polymer. Polyurethane elastic fiber described in Crab.
[ 8 ] One of the above [1] to [ 7 ], wherein the ratio of the major axis to the minor axis (= major axis ÷ minor axis) of the cross section of the single yarn of the polyurethane elastic fiber is 1.2 or more and 3.0 or less. The polyurethane elastic fiber described.
[ 9 ] The fabric containing the polyurethane elastic fiber according to any one of the above [1] to [ 8 ].

The polyurethane elastic fiber containing the inorganic deodorant according to the present invention can eliminate the wear of the knitting needles of the knitting machine at the time of knitting, and can further exhibit high deodorizing performance.

Hereinafter, embodiments for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail. The present invention is not limited to the following embodiments, and can be variously modified and implemented within the scope of the gist thereof.
The present embodiment is a polyurethane elastic fiber having a reducing viscosity of 1.40 or more and 3.80 or less and containing an inorganic deodorant.
By keeping the reduced viscosity within the above range, the inorganic deodorant can be uniformly dispersed in the polymer, and the generation of agglomerates of the deodorant in the product yarn can be suppressed, thus preventing needle wear during knitting. In addition, the deodorant performance can be improved because there are few agglomerates of the deodorant, which is a cause of deteriorating the deodorant performance. If the reduced viscosity is less than 1.40, it becomes difficult to more uniformly disperse the inorganic deodorant in the polyurethane polymer. Therefore, the reduced viscosity is 1.40 or more, and from the viewpoint of more uniformly dispersed. , 1.50 or more, more preferably 1.60 or more. On the other hand, when the reducing viscosity exceeds 3.80, the fluidity of the polymer chain decreases and it becomes difficult to mix the inorganic deodorant. Therefore, the reducing viscosity is 3.80 or less, and from the viewpoint of mixing. Is preferably 3.30 or less, more preferably 2.80 or less.

The polyurethane elastic fiber of the present embodiment is a fiber obtained by spinning a polyurethane polymer. As for the method for producing the raw material polymer of the polyurethane elastic fiber of the present embodiment, a known technique of polyurethane reaction can be used. A high molecular weight polyol, for example, polyalkylene ether glycol and diisocyanate are reacted under the condition of excess diisocyanate to synthesize a urethane prepolymer having an isocyanate group at the terminal, and then this urethane prepolymer is used as a bifunctional amine or the like. A polyurethane polymer can be obtained by carrying out a chain extension reaction with an active hydrogen-containing compound. From the viewpoint of obtaining a uniform polymer with less gel, the molar ratio of diisocyanate to polymer polyol (diisocyanate / polymer polyol) is preferably 1.70 or less, more preferably 1.65 or less, still more preferably. Is 1.60 or less.

Examples of the high-polymer polyol include various diols consisting of substantially linear homo or copolymers, for example, polyester diol, polyether diol, polyester amide diol, polyacrylic diol, polythioester diol, polythio ether diol, and polycarbonate diol. Examples thereof include a mixture thereof, a copolymer thereof, and the like, preferably polyalkylene ether glycol, for example, polyoxyethylene glycol, polyoxypropylene glycol, polytetramethylene ether glycol, polyoxypentamethylene glycol, tetramethylene. A copolymerized polyether glycol composed of a group and a 2,2-dimethylpropylene group, a copolymerized polyether glycol composed of a tetramethylene group and a 3-methyltetramethylene group, a mixture thereof and the like. Among these, polytetramethylene ether glycol and a copolymerized polyether glycol composed of a tetramethylene group and a 2,2-dimethylpropylene group are particularly preferable as the polymer polyol from the viewpoint of exhibiting excellent elastic function.

The number average molecular weight calculated from the hydroxyl value of the polymer polyol is preferably 500 or more, more preferably 1000 or more, and even more preferably 1500 or more in order to obtain excellent elastic performance. On the other hand, the number average molecular weight calculated from the hydroxyl value of the polymer polyol is preferably 5000 or less, more preferably 3000 or less, still more preferably 2500 or less, from the viewpoint of obtaining a highly heat-resistant yarn.

Examples of the diisocyanate include aliphatic, alicyclic, and aromatic diisocyanates. For example, 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,4- or 2,6-tolylene diisocyanate, m- or p-xylylene diisocyanate, α, α, α', α'. -Tetramethyl-xylylene diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4'-dicyclohexyl diisocyanate, 1,3- or 1,4-cyclohexamethylene diisocyanate, 3- (α-isocyanatoethyl) phenyl isocyanate, 1 , 6-Hexamethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, mixtures thereof, copolymers thereof and the like, and among these, 4,4'-diphenylmethane diisocyanate is particularly preferable.

Examples of the chain extender having an active hydrogen-containing compound, that is, a polyfunctional active hydrogen atom include hydrazine, polyhydrazine, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, and 1,3-butane. Diamine, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2,2-dimethyl-1,3-propanediol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, Low molecular weight diols such as phenyldiethanolamine, ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 2-methyl-1,5-pentanediamine, triethylenediamine, m-xylylenediamine, piperazin, o-, m -Or p-phenylenediamine, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, 1,6-hexamethylenediamine, N, N'-(methylenedi-4,1-phenylene) bis [2- (ethylamino ) -Urea] and other bifunctional amines.

These chain extenders can be used alone or in admixture. Bifunctional amines are preferred over low molecular weight diols, with at least one selected from the group ethylenediamine, 1,2-propylenediamine, 1,3-diaminocyclohexane, and 2-methyl-1,5-pentadiamine 5-40. Ethylenediamine mixtures containing mol% are preferred, with ethylenediamine alone being more preferred.

Examples of the terminal terminator having a monofunctional active hydrogen atom include methanol, ethanol, 2-propanol, 2-methyl-2-propanol, 1-butanol, 2-ethyl-1-hexanol, 3-methyl-1-. Monoalcohols such as butanol, monoalkylamines such as isopropylamine, n-butylamine, t-butylamine, 2-ethylhexylamine, diethylamine, dimethylamine, di-n-butylamine, di-t-butylamine, diisobutylamine, di- Examples thereof include dialkylamines such as 2-ethylhexylamine and diisopropylamine. These can be used alone or in combination. Monoalkylamines or dialkylamines, which are monofunctional amines, are preferable to monoalcohols.

Regarding the operation of the polyurethaneization reaction, an amide-based polar solvent such as dimethylformamide, dimethylsulfoxide, or dimethylacetamide (DMAc) can be used during the synthesis of the urethane prepolymer or the reaction between the urethane prepolymer and the active hydrogen-containing compound. It is preferably dimethylacetamide (DMAc).

The polyurethane polymer composition may contain various stabilizers, pigments and the like, and for example, hindered phenol-based, benzotriazole-based, benzophenone-based, phosphorus-based and various hindered amine-based antioxidants, magnesium stearate. Metal soaps such as titanium oxide, iron oxide, zinc oxide, cerium oxide, magnesium oxide and other inorganic substances, carbon black and various pigments, antibacterial agents and deodorants containing silver, zinc and their compounds, etc. An antistatic agent, a nitrogen oxide trapping agent, a thermal oxidation stabilizer, a light stabilizer and the like may be contained in combination.

The polyurethane polymer thus obtained can be formed into fibers by a known dry spinning, melt spinning, wet spinning method or the like to obtain polyurethane elastic fibers. Further, polyurethane polymers polymerized using different raw materials may be mixed and spun at the pre-spinning stage.

The polyurethane elastic fiber of the present embodiment can be used by containing a surface treatment agent in order to reduce the resistance at the time of unwinding and the frictional property at the time of use. The surface treatment agent may be kneaded into the undiluted spinning solution in advance, or may be applied by a known method such as roll oiling, guide oiling, or spray oiling before being wound on a paper tube at the time of spinning. Alternatively, the surface treatment agent may be applied in the step of winding without applying the surface treatment agent and then rewinding to make another winding body.

The composition of the surface treatment agent is not particularly limited, but is a higher fatty acid metal such as polydimethylsiloxane, polyester-modified silicone, polyether-modified silicone, amino-modified silicone, mineral oil, mineral fine particles, for example, silica, colloidal alumina, talc, etc. Use in combination with salt powders such as magnesium stearate (StMg), calcium stearate, higher aliphatic carboxylic acids, higher aliphatic alcohols, paraffins, polyethylene and other known surface treatment agents such as solid wax at room temperature. Can be done.

The method for spinning the polyurethane elastic fiber of the present embodiment is not particularly limited, but it is preferable to dry-spun a polyurethane spinning stock solution obtained by dissolving a polyurethane polymer in an amide-based polar solvent. Compared with melt spinning and wet spinning, dry spinning can form the strongest physical cross-linking due to hydrogen bonds between hard segments.

As a method for obtaining a polyurethane elastic fiber having a reduced viscosity of the polyurethane elastic fiber of the present embodiment, a method for optimizing the ratio of a terminal terminator and a chain extender during polyurethane polymerization or a method for reacting a prepolymer with an active hydrogen-containing compound is used. The ratio of the amino group in the monofunctional or bifunctional active hydrogen-containing compound and the active hydrogen-containing functional group consisting of a hydroxyl group to the isocyanate group in the prepolymer of the above is in the range of 0.95 to 1.05. Examples thereof include a method of optimizing the temperature of hot air supplied to the spinning machine in the range of 250 to 350 ° C. in the case of dry spinning.

The polystyrene-equivalent number average molecular weight measured by GPC of the polyurethane elastic fiber of the present embodiment is preferably 160,000 or more and 400,000 or less. By keeping the number average molecular weight within the above range, the inorganic deodorant can be uniformly dispersed in the polymer, and the generation of agglomerates of the deodorant in the product yarn can be suppressed, so that needle wear during knitting can be prevented. In addition to being able to prevent it, the deodorizing performance can be improved because there are few agglomerates of the deodorant that cause the deodorizing performance to deteriorate. If the number average molecular weight is less than 160,000, it becomes difficult to uniformly disperse the inorganic deodorant in the polyurethane polymer. Therefore, the number average molecular weight is 160,000 or more, and from the viewpoint of more uniform dispersion. 170,000 or more is more preferable, and 180,000 or more is more preferable. When the number average molecular weight exceeds 400,000, the fluidity of the polymer chain decreases and it becomes difficult to mix the inorganic deodorant, so it is 400,000 or less, and from the viewpoint of mixing, the number average molecular weight is more than 350,000. It is preferable, more preferably 300,000 or less. As a method for obtaining a polyurethane elastic fiber having a number average molecular weight in terms of polystyrene measured by GPC of the polyurethane elastic fiber of the present embodiment, a method for optimizing the ratio of a terminal terminator and a chain extender during polyurethane polymerization or a prepolymer The ratio of the amino group in the monofunctional or bifunctional active hydrogen-containing compound and the active hydrogen-containing functional group consisting of the hydroxyl group to the isocyanate group in the prepolymer when reacting with the active hydrogen-containing compound is 0.95. To 1.05, and in the case of dry spinning, a method of optimizing the hot air temperature supplied to the spinning machine in the range of 250 to 350 ° C. can be mentioned.

The molecular weight distribution (Mw / Mn) represented by the ratio of the polystyrene-equivalent weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by GPC of the polyurethane elastic fiber of the present embodiment is 1.50 or more and 2.10 or less. Is preferable. When the molecular weight distribution is in this range, the dispersibility of the inorganic deodorant becomes particularly good. It is not clear why the dispersibility of the deodorant is improved by setting the molecular weight distribution to a specific range, but by controlling the molecular weight distribution to a certain width, the mixability of the deodorant and the polymer is improved. It is presumed that the aggregation of the deodorant can be suppressed by this. The range of the more preferable molecular weight distribution (Mw / Mn) is 1.55 or more and 2.00 or less, more preferably 1.60 or more and 1.90 or less, and even more preferably 1.60 or more and 1.80 or less. As a method for controlling the molecular weight distribution within the above range, the molecular weight distribution (Mw / Mn) represented by the ratio of the weight average molecular weight in terms of polystyrene and the number average molecular weight measured by GPC by the same method as that of polyurethane elastic fiber is obtained. A method of using a polymer diol in the range of 1.00 to 1.50, a method of shortening the residence time in the reactor during the polymerization reaction of polyurethane, a method of lowering the temperature during the polymerization reaction, and spinning in the case of dry spinning. A method of setting the temperature of the hot air supplied to the machine in the range of 250 to 350 ° C. can be mentioned.

The inorganic deodorant contained in the polyurethane elastic fiber of the present embodiment is a metal oxide or composite metal containing at least one metal atom selected from the group consisting of Ti, Zr, Ag, Zn, Al, and Si. It is preferable to contain any one of oxides and metal phosphates. More specifically, a composite metal oxide composed of silicon dioxide and zinc oxide, a composite metal oxide composed of silicon dioxide and zirconium oxide, a metal phosphate such as zirconium phosphate, titanium phosphate, and aluminum dihydrogen dihydrogen phosphate, Examples thereof include silicon dioxide, zinc oxide, aluminum oxide and the like, and these may be used in combination.
From the viewpoint of obtaining high deodorizing properties, the inorganic deodorant can be any of a composite metal oxide composed of silicon dioxide and zinc oxide, a composite metal oxide composed of silicon dioxide and zirconium oxide, and a metal phosphate. It is preferable to include one or more. From the viewpoint of obtaining higher deodorizing performance, metal phosphate is preferable, and zirconium phosphate is particularly preferable. Typical chemical formulas of zirconium phosphate are (ZrO) ₂ (HPO ₄ ) ₂ , HZr ₂ (PO ₄ ) ₃ , Zr (HPO ₄ ) ₂ , Zr (PO ₄ ) (H ₂ PO ₄ ), and their Examples include hydrates.

The particle size d50 measured by the particle size distribution meter of the inorganic deodorant contained in the polyurethane elastic fiber of the present embodiment is preferably less than 5 μm, more preferably 3 μm, from the viewpoint of suppressing filter clogging and aggregation. Is less than.

The polyurethane elastic fiber of the present embodiment contains particles having a particle size of 6 μm or more in a particle size measurement obtained by measuring a solution of the polyurethane elastic fiber in dimethylacetamide (DMAc) with a wet particle size distribution meter. It is preferable that there is no such thing. The definition of "not included" described here is that when the volume frequency% of the particles of each particle size measured by the particle size distribution meter is less than 0.01%, the particles of that particle size (particle size). Was not included. When the particle size measured from the solution of the thread is 6 μm or more, the inorganic deodorant is contained in the thread manufacturing process even if the particle size is less than 6 μm at the time of manufacturing. It is possible that agglomeration has occurred, and there is a possibility that the knitting needle wear and deodorant performance will deteriorate. From the viewpoint of deodorizing performance and knitting needle wear, the particle size measured by melting the yarn is preferably more than 0 μm and 4 μm or less, and more preferably more than 0 μm and 3 μm or less.

The content of the inorganic deodorant of the polyurethane elastic fiber of the present embodiment is preferably 1 part by weight or more and 10 parts by weight or less with respect to 100 parts by weight of the polyurethane polymer. If it is less than 1 part by weight, it is difficult to exhibit sufficient deodorizing performance, while if it exceeds 10 parts by weight, it is difficult to obtain a yarn in which the inorganic deodorant is uniformly dispersed. From the viewpoint of deodorizing performance, the lower limit of the content of the inorganic deodorant is more preferably 2 parts by weight or more, still more preferably 3 parts by weight or more. From the viewpoint of obtaining uniformly dispersed yarn, the upper limit of the content of the inorganic deodorant is more preferably 8 parts by weight or less, still more preferably 6 parts by weight or less.

The polyurethane elastic fiber of the present embodiment contains a magnesium salt of a long-chain fatty acid having 10 to 20 carbon atoms with respect to 100 parts by weight of the polyurethane polymer and 0.01 to 0.50 with respect to 100 parts by weight of the polyurethane polymer. It is preferably further contained by weight. If the content of the magnesium salt is less than 0.01 parts by weight, the smoothness of the yarn surface deteriorates, which may cause problems such as yarn breakage and needle wear during knitting. Therefore, 0.01 parts by weight or more. Is preferable, and more preferably 0.02 parts by weight or more. On the other hand, if the content of the magnesium salt exceeds 0.50 parts by weight, the deodorizing performance deteriorates due to the interaction with the inorganic deodorant, so 0.50 parts by weight or less is preferable, and more preferably 0. It is .30 parts by weight or less, more preferably 0.20 parts by weight or less, still more preferably 0.15 parts by weight or less.
Examples of magnesium salts of long-chain fatty acids having 10 to 20 carbon atoms include magnesium stearate (StMg), magnesium 12-hydroxystearate, magnesium palmitate, magnesium oleate, magnesium laurate and the like. The magnesium salt of a long chain fatty acid having 10 to 20 carbon atoms may be used alone or in combination. From the viewpoint of suppressing needle wear, it is preferable to use magnesium stearate (StMg) or magnesium 12-hydroxystearate.

The cross-sectional shape of the single yarn constituting the polyurethane elastic fiber may be a perfect circle or a deformed cross section such as an ellipse, but from the viewpoint of further improving needle wear and improving deodorizing performance, a deformed cross section such as an ellipse. Is preferable. The deformed cross section is preferably an ellipse or a dumbbell shape, and the ratio of the major axis to the minor axis (major axis / minor axis) of the single thread cross section is preferably 1.2 or more and 3.0 or less. When the ratio of the major axis to the minor axis of the single yarn cross section is within this range, the friction between the contact surface between the needle and the yarn during knitting is alleviated, needle wear can be suppressed, and deodorization is achieved by improving the specific surface area. Performance can be improved. From the viewpoint of needle wear and deodorizing performance, the ratio of the major axis to the minor axis of the single yarn cross section is more preferably 1.5 or more and 2.7 or less, and further preferably 1.7 or more and 2.5 or less.

The polyurethane elastic fiber of the present embodiment is a natural fiber such as cotton, silk and wool, a polyamide fiber such as nylon 6 and nylon 66, a polyester fiber such as polyethylene terephthalate, polytrimethylene terephthalate and polytetramethylene terephthalate, and a cationic dyeable polyester. No spots can be obtained by cross-knitting with fibers, copper-ammonia regenerated rayon, biscous rayon, acetate rayon, etc., or by using these fibers to make processed yarn by coating, entanglement, twisting, etc. High-quality fabric can be obtained. In particular, fabrics using polyurethane elastic fibers have a large production volume and are supplied as bare yarns, and are therefore suitable for warp knits that are greatly affected by the quality of the raw yarns. The warp knitted fabric includes a power net, a satin net, a Russell lace, a two-weight ricott, and the like. By using the polyurethane elastic fiber of the present embodiment, a high-quality fabric with few streaks in the warp direction can be obtained.

The fabric using the polyurethane elastic fiber of the present embodiment is used for swimwear, girdles, bras, tights, pantyhose, waistbands, bodysuits, spats, stretch sportswear, stretch outerwear, medical wear, stretch lining, etc. be able to.

The polyurethane elastic fiber of the present embodiment can be suitably used for sanitary materials such as sanitary products and disposable diapers, has good smoothness, and has a small fluctuation in friction, so that high productivity and product stability can be achieved. can get.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. Further, in the following examples, the present invention will be described using polyurethane elastic fibers obtained by spinning, but the present invention also includes polyurethane elastic fibers isolated from products such as clothing and sanitary materials. The measurement methods, evaluation methods, etc. used in the following examples and comparative examples were as follows.

(1) Identification of deodorant in polyurethane elastic fiber and quantification method of content The polyurethane elastic fiber is wrapped around a glass plate and analyzed by XRD (Rigaku Ultima-IV), and the analyzed spectrum is collated with the data on the database. Can identify the chemical composition of the deodorant contained in. After the identification of the deodorant by XRD is completed, a sample is prepared by winding the polyurethane elastic fiber around a PP film with holes without gaps, and analyzed by XRF (Rigaku ZSX-100e) to obtain the deodorant. The content of the deodorant can be quantified from the detection intensity of the constituent elements. When quantifying, a calibration curve using the same deodorant as the deodorant contained may be used, if necessary.

(2) Measurement of reduced viscosity of polyurethane elastic fiber Weigh 2 g of polyurethane elastic fiber, add 50 g of petroleum ether, and repeat the operation of stirring for 1 minute twice to remove the surface treatment agent, and then in an environment of 20 ° C. Air dry for 24 hours. 0.5 g of the dried polyurethane elastic fiber is precisely weighed, 99.5 g of dimethylacetamide (DMAc) is precisely weighed and mixed, and the mixture is stirred with a stirrer chip overnight to obtain a dilute solution of dimethylacetamide (DMAc) of the polyurethane elastic fiber. To make. Inorganic deodorant is settled in the prepared dilute solution with a centrifuge (10000 rpm x 20 minutes, 15 ° C.), and only the finished solution is taken out and used as a sample solution.
Let η0 be the number of seconds of drop when only dimethylacetamide (DMAc) is measured with an Ostwald viscosity tube at a measurement atmosphere temperature of 20 ° C., and η be the number of seconds of drop of the sample solution prepared above. The measurement was performed 3 times, and using the average value, the following formula:
Reduction viscosity ηsp / c = (η / η0-1) /0.5
To determine the reduced viscosity.

(3) Measurement of number average molecular weight and weight average molecular weight by GPC In a dimethylacetamide solution containing 0.02 mol / L of LiBr, a sample (polyurethane elastic fiber) is dissolved so that the solid content concentration becomes 0.25% by weight. And use it as a measurement sample. The prepared sample is measured with GPC-101 manufactured by Shodex under the conditions shown below. As for the molecular weight of the polyurethane compound, all the polystyrene standard samples (SM-105) manufactured by Shodex are measured, and the number average molecular weight and the weight average molecular weight of the measured samples are calculated from the calibration curve prepared from the peak top molecular weight.
Column: From the injection side, (1) KD-G, (2) KD-806M, (3) KD-806M, (4) KD-802.5, (5) KD-801 (all of the above are manufactured by Shodex).
Column oven temperature: 60 ° C
Detector: RI-71S (manufactured by Shodex)
Flow rate: 1.0 ml / min
Eluent: Dimethylacetamide solution containing LiBr at a concentration of 0.02 mol / L

(4) Measurement of particle size of a solution of polyurethane elastic fiber dissolved in dimethylacetamide (DMAc) Weigh 3 g of polyurethane elastic fiber, add 97 g of dimethylacetamide (DMAc), stir at room temperature for 24 hours, and 3 wt% of polyurethane elastic fiber. Make a solution. For a sample that is difficult to dissolve, stirring may be performed while heating at 50 ° C. Using the obtained polyurethane solution, the solvent of the device was replaced with dimethylacetamide (DMAc) and dispersed by using LS 13 320 (wet laser diffraction scattering method particle size distribution measuring device, equipped with PIDS) manufactured by Beckman Coulter. The solvent refractive index is measured at 1.439 and the sample refractive index is 1.57. The sample is injected so that the relative intensity of the detector is in the range of 7 to 12%. In the particle size distribution chart obtained by this measurement, the presence or absence of particles exceeding the respective particle sizes of 6 μm, 4 μm, and 3 μm is read from the chart. When the volume frequency% of the particles of each particle size is less than 0.01%, it is defined that the particles of the particle size are not included.

(5) Ratio of major axis and minor axis of the single thread cross section of polyurethane elastic fiber Take an SEM photograph of the cross section of polyurethane elastic fiber, measure the major axis and minor axis of the single thread, and divide the major axis by the minor axis. Ask for. For the measurement, 5 threads are sampled and measured at intervals of 1 m or more from the same winding body, and the average value is taken as the major axis / minor axis ratio. In the case of multifilament, the major and minor diameters of all single yarns are measured and calculated. One polyurethane elastic fiber is sandwiched between two sheets of thick paper with double-sided tape attached, and the polyurethane elastic fiber protruding from it is cut with a razor blade at the edge of the thick paper, and SEM is used so that the cross section can be observed from the front. Set on the stage and observe. The software "SEM Control User Interface ver.3.02" manufactured by JEOL Ltd. is used for measuring the major axis and the minor axis.

(6) Evaluation of knitting needle wear A knitting needle (GROZ-BECKERT Co., Ltd. 70. The yarn is continuously run for 5 hours while being hooked on 34 G043), the running portion of the yarn of the knitting needle after 5 hours is observed by SEM, and the degree of wear is judged by the following four-step evaluation criteria.
4: No wear 3: Slight wear 2: Slight wear 1: Significant wear The less wear the needle has, the more stable it is without changing the needle even if the thread is used continuously for a long time in the knitting machine. Production can be expected.

(7) Measurement of deodorizing performance A knitted fabric sample of 100% polyurethane elastic fiber was prepared, and after adjusting the humidity for 24 hours or more in an environment of 20 ° C. and 65% humidity RH, 0.20 g was precisely weighed and placed in a tedler bag. put in. 3 L of ammonia gas having a concentration of 100 ppm is injected into a tedler bag, and the residual gas concentration after storage for 2 hours in an environment of 20 ° C. is measured with a detector tube (manufactured by Komei Rikagaku Kogyo Co., Ltd.). Ammonia gas having a concentration of 100 ppm is diluted and adjusted using dry air. Perform the same evaluation without using a sample, and use it as a blank test. The following formula:
Deodorizing performance (%) = 100 x (residual ammonia gas concentration in blank test-residual gas concentration in sample) / Deodorizing performance (%) by calculating the reduction rate of residual gas concentration according to the residual ammonia gas concentration in the blank test. And.

[Example 1]
2000 g of polytetramethylene ether glycol having a number average molecular weight of 2000 and 400 g of 4,4'-diphenylmethane diisocyanate having a molecular weight distribution of 1.20 defined by dividing the weight average molecular weight in terms of polystyrene by GPC by the number average molecular weight. Was reacted at 60 ° C. for 3 hours under stirring under a dry nitrogen atmosphere to obtain a polyurethane prepolymer having an isocyanate-capped end. After cooling this to room temperature, dimethylacetamide was added and dissolved to obtain a polyurethane prepolymer solution. Separately, an amine solution prepared by dissolving ethylenediamine and diethylamine in dry dimethylacetamide was added so that the ratio of the isocyanate group in the urethane prepolymer to the amino group in the amine solution was 1: 1.03, and the temperature was 10 ° C. By reacting while cooling, a polyurethane solution having a polyurethane solid content concentration of 30% by mass and a viscosity of 450 Pa · s (30 ° C.) was obtained.

1 wt% of 4,4'-butylidenebis (3-methyl-6-t-butylphenol) and 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5 with respect to the polyurethane solid content -Chlorobenzotriazole 0.5 wt% and zirconium phosphate (d50: 0.9 μm, chemical formula: Zr (HPO ₄ ) 2.nH ₂ O {in the formula, n is 0 to ₂ }) 4 wt%, Magnesium stearate is weighed to 0.1 wt%, added to dimethylacetamide, dispersed with a homomixer to prepare a 15 wt% dispersion, and then mixed with a polyurethane solution to obtain a uniform solution. After that, defoaming was performed at room temperature under reduced pressure, and this was used as a spinning stock solution.
This undiluted spinning solution is dry-spun at a winding speed of 800 m / min and a hot air temperature of 300 ° C. using a spun consisting of two round holes, and is focused by a false twisting device using compressed air, and then a surface treatment agent. Was applied to the polyurethane elastic fiber in an amount of 4.0% by mass and wound on a paper tube to obtain a winding package of the polyurethane elastic fiber of 22 dtex / 2 filament. As the surface treatment agent, an oil agent composed of 67% by mass of polydimethylsiloxane, 30% by mass of mineral oil, and 3.0% by mass of amino-modified silicone was used.

[Examples 2 to 4]
Polyurethane elastic fibers were obtained in the same manner as in Example 1 except that the deodorant was changed to a composite metal salt composed of titanium phosphate, aluminum dihydrogen tripolyphosphate, zinc oxide and silicon dioxide, respectively.

[Examples 5 to 8]
Polyurethane elastic fibers were obtained in the same manner as in Example 1 except that the ratio of ethylenediamine to diethylamine in the amine solution was adjusted so that the number average molecular weight of the polyurethane elastic fibers became the values shown in Table 1 below.

[Example 9 (referred to as Reference Example 9) ]
Polyurethane as in Example 1 except that the polymerization reaction of the prepolymer and the amine solution was carried out at room temperature (25 ° C.) using polytetramethylene ether glycol having a number average molecular weight of 2000 having a molecular weight distribution of 1.70. Elastic fibers were obtained.

[Example 10]
Polyurethane as in Example 1 except that the polymerization reaction of the prepolymer and the amine solution was carried out at room temperature (25 ° C.) using polytetramethylene ether glycol having a number average molecular weight of 2000 having a molecular weight distribution of 1.60. Elastic fibers were obtained.

[Examples 11 to 14]
Polyurethane elastic fibers were obtained in the same manner as in Example 1 except that the content of zirconium phosphate was changed to the amount shown in Table 1 below.

[Examples 15 to 18]
Polyurethane elastic fibers were obtained in the same manner as in Example 1 except that the content of magnesium stearate was changed to the amount shown in Table 1.

[Example 19]
Polyurethane elastic fibers having a flat cross section were obtained by the same method as in Example 1 except that the content of magnesium stearate was changed to 0.01% by weight and spinning was performed using a spun consisting of two slit-shaped holes. rice field.

[Example 20]
Polyurethane elasticity with a flat cross section was carried out by the same method as in Example 1 except that the deodorant was changed to a composite metal oxide composed of zinc oxide and silicon dioxide and spun using a spun having two slit-shaped holes. Obtained fiber.

[Comparative Example 1]
Polyurethane elastic fibers were obtained in the same manner as in Example 1 except that they did not contain a deodorant.

[Comparative Example 2]
Using polytetramethylene ether glycol having a number average molecular weight of 2000 and a molecular weight distribution of 1.70, the polymerization reaction of the prepolymer and the amine solution was carried out at room temperature (25 ° C.), and the number average molecular weight is shown in Table 1 below. Polyurethane elastic fibers were obtained in the same manner as in Example 1 except that the ratio of ethylenediamine and diethylamine in the amine solution and the spinning conditions were changed so as to have the same values.

[Comparative Example 3]
Using polytetramethylene ether glycol having a number average molecular weight of 2000 and a molecular weight distribution of 1.70, the polymerization reaction of the prepolymer and the amine solution was carried out at room temperature (25 ° C.), and the number average molecular weight is shown in Table 1 below. The same as in Example 1 except that the ratio of ethylenediamine and diethylamine in the amine solution and the spinning conditions were changed so that the values would be the same, and a composite metal oxide composed of zinc oxide and silicon dioxide was used as the deodorant. Polyurethane elastic fibers were obtained.

[Comparative Example 4]
Using polytetramethylene ether glycol having a number average molecular weight of 2000 and a molecular weight distribution of 1.70, the polymerization reaction of the prepolymer and the amine solution was carried out at room temperature (25 ° C.), and the number average molecular weight is shown in Table 1 below. Polyurethane elastic fibers were obtained in the same manner as in Example 1 except that the ratio of ethylenediamine and diethylamine in the amine solution and the spinning conditions were changed so as to have the same values.

The production conditions in each of the above Examples and Comparative Examples, various properties of the obtained polyurethane elastic fibers, and the like are shown in Table 1 below.

A circular knitted fabric was prepared using the polyurethane elastic fiber of Example 1 and the polyester fiber of 84 dt / 36f, rinsed with soft water, mangled, and then dry-heated at 190 ° C. for 1 minute to set the mixing ratio of the polyurethane elastic fiber to 10. %, A fabric having a grain size of 140 g / m ² was obtained. This fabric has a very good texture, and when an ammonia gas removal performance evaluation test was conducted at the Kaken Test Center by the method specified in the SEK mark textile product certification standard, the ammonia gas removal performance was 91%. Demonstrated very high deodorizing performance. If this fabric is used, it can be expected that clothing having a very good texture and high deodorizing performance can be obtained by further undergoing a dyeing finishing process and a sewing process.

By using the polyurethane elastic fiber according to the present invention, it is possible to eliminate the wear of the knitting needle during knitting using the polyurethane elastic fiber, continuous production of the fabric is possible, and productivity can be improved, which is even higher. It is possible to obtain a fabric that exhibits deodorizing performance.

Claims (9)

A polyurethane elastic fiber having a reduced viscosity of 1.40 or more and 3.80 or less and containing an inorganic deodorant, and having a polystyrene-equivalent weight average molecular weight (Mw) and a number average molecular weight (Mw) measured by GPC. A polyurethane elastic fiber having a molecular weight distribution (Mw / Mn) represented by a ratio of Mn) of 1.50 or more and 2.10 or less . The polyurethane elastic fiber according to claim 1, wherein the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is 160,000 or more and 400,000 or less. The inorganic deodorant is a metal oxide, a composite metal oxide, or a metal phosphate containing at least one metal atom selected from the group consisting of Ti, Zr, Ag, Zn, Al, and Si. The polyurethane elastic fiber according to claim 1 or 2 , which comprises any one or more of the above-mentioned. The inorganic deodorant is one of a metal phosphate containing Ti, Zr or Al, a composite metal oxide composed of silicon dioxide and zinc oxide, or a composite metal oxide composed of silicon dioxide and zirconium oxide. The polyurethane elastic fiber according to any one of claims 1 to 3 , which comprises the above. The invention according to any one of claims 1 to 4 , which does not contain particles of 6 μm or more in the particle size measurement by a wet particle size distribution meter in DMAc of a solution of the polyurethane elastic fiber dissolved in dimethylacetamide (DMAc). Polyurethane elastic fiber. The polyurethane elastic fiber according to any one of claims 1 to 5 , wherein the content of the inorganic deodorant is 1 to 10 parts by weight with respect to 100 parts by weight of the polyurethane polymer. The invention according to any one of claims 1 to 6 , further comprising 0.01 to 0.50 parts by weight of a magnesium salt of a long-chain fatty acid having 10 to 20 carbon atoms with respect to 100 parts by weight of the polyurethane polymer. Polyurethane elastic fiber. The polyurethane elasticity according to any one of claims 1 to 7 , wherein the ratio of the major axis to the minor axis (= major axis ÷ minor axis) of the cross section of the single yarn of the polyurethane elastic fiber is 1.2 or more and 3.0 or less. fiber. A fabric containing the polyurethane elastic fiber according to any one of claims 1 to 8 .