JPH09291445A - Stretchable weft knit fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To impart a weft knit fabric useful as sweater, etc., with pH buffering property, antibacterial property, deodorizing property, antipilling property, antistaticity, water-absorptivity, heat retaining property and dryability and to keep the stretchability of the ground texture of the weft knit fabric by forming a ground texture with a polyurethane elastic conjugate yarn and a specific non-stretchable yarn. SOLUTION: The ground texture of the subject fabric is composed of a polyurethane elastic conjugate yarn (e.g. a covering yarn having a polyurethane elastic fiber at the core part) and a non-stretchable yarn containing moisture- absorbing crosslinked acrylate fiber in an amount of >=20% (e.g. a spun yarn composed of a moisture-absorbing crosslinked acrylate fiber and an acrylic fiber).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat knitted fabric used for a sweater or the like, and more specifically, by using a hygroscopic crosslinked acrylic fiber as a constituent material thereof,
The flat knitted fabric retains the harmonized function of the PH buffering property, antibacterial property, deodorant property, anti-pill property, antistatic property, water absorption property, heat retaining property, and easiness of drying which the fiber possesses, and The purpose of the present invention is to provide a soft-fit type flat knitted sweater which has stretchability and has a stretchable texture, and is intended to improve quality such as defective dimensions.

[0002]

2. Description of the Related Art Conventionally, there has been a flat knitted sweater having stretchability, which is a combination of acrylic fiber and elastic elastic yarn. However, due to unstable characteristics of acrylic fibers against heat, such as yellowing and dimensional change in a high temperature set, there are many problems such as dimensional defects and discoloration, and stable production cannot be performed at present. The cause of yellowing, dimensional defects, etc. is 1 because the elastic elastic yarn mainly used for the mating material is an ether type polyurethane urea type elastic yarn.
Unless it is dry heat treated at 80 ° C or higher, the settability may be poor.

Acrylic fibers are widely used in knit products such as outerwear and innerwear such as sweaters because of their characteristics similar to wool and their good texture. However, recent consumer demands include antibacterial properties, deodorant properties, heat retention properties, anti-pill properties,
There is an increasing demand for addition of functions such as antistatic property, water absorption property, easiness of drying, and PH buffering property which is said to be good for health.

[0004] In order to meet such a demand, conventionally, after forming into a cloth, a post-processing is carried out by using a processing agent suitable for each characteristic to give a functional property. There were various problems such as the problem and the difficulty of processing to hold many functions in parallel.

[0005]

DISCLOSURE OF THE INVENTION The present invention has improved the above-mentioned problems of the prior art and, in addition, has antibacterial properties, deodorant properties, anti-pill properties, antistatic properties, PH buffer properties, etc. which are highly desired by users. The present invention relates to a method for producing a flat knitted fabric for a sweater, which has characteristics as harmony functions. First, in order to improve the quality of acrylic fibers such as yellowing and dimensional defects, we have investigated polyurethane elastic yarns, which are the core yarns of stretchable yarns, raw yarns that possess low-temperature setting characteristics that match acrylic processing conditions, and antibacterial properties. , Deodorant, anti-pill,
In order to combine properties such as antistatic property and PH buffering property as a harmony function and to enhance washing durability, the present invention has been advanced by studying an acrylic yarn having these properties together.

[0006]

According to the present invention, in a flat knitted fabric in which a non-stretchable yarn and a polyurethane elastic composite yarn form a ground structure, the non-stretchable yarn contains 20% of a hygroscopic crosslinked acrylate fiber. It is a flat knitted fabric that is a yarn including the above.

The hygroscopic cross-linked acrylate fiber is introduced by introducing a cross-linking structure into the acrylic fiber by hydrazine treatment to adjust the increase of nitrogen content within the range of 1.0 to 8.0% by weight and remaining by hydrolysis. 1.0 of the amount of nitrile group
To 5.0 meq / g, a carboxyl group is introduced to the rest, and then 50 to 90 mo of the carboxyl group is introduced.
1% is a metal salt type of one or more selected from Mg, Ca, Cu, Zn, Al, Ag and Fe, and the final heat treatment is performed at a dry heat temperature of 100 to 230 ° C. The fiber obtained by the above method has a temperature of 20 ° C. and 65% RH.
Has a saturated moisture absorption rate of 15 to 35% by weight, and has antibacterial properties, deodorant properties, anti-pill properties, antistatic properties, PH buffering properties and the like as harmony functions.

When the fiber is used as a constituent material of a flat knitted fabric, it is preferable to spun it as a short fiber into a yarn. Although the fiber alone, that is, a spun yarn of 100 wt% is also conceivable,
From the viewpoint of cost, post-processability such as spinnability, and the minimum mixing ratio for maintaining the characteristics of the fiber, 20 wt% or more, preferably 30 wt% or more is preferable. The upper limit is not particularly limited, but about 70 wt% is preferable for the above reason. Acrylic fiber is usually suitable as a material to be mixed with the hygroscopic crosslinked acrylate fiber, and the spinnability is also improved.

The polyurethane elastic fiber having good heat setting property (dimensional stability) at low temperature used in the present invention has a urethane group concentration obtained by spinning a polyurethane elastomer composed of a high molecular diol, an organic diisocyanate and a low molecular diol. 1,500 or more polyurethane filament yarns. Examples of the polymer diol used in the present invention include polytetramethylene glycol, poly ε-caprolactone, and polybutylene adipate. Examples of organic diisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, m-phenylene diisocyanate, hexamethylene diisocyanate and tetramethylene diisocyanate. , 2,4-naphthalene diisocyanate, m-xylene diisocyanate, 4,4′-diisocyanate dicyclohexane, 4,4′-diisocyanate dicyclohexylmethane, isophorone diisocyanate and the like. These may be used alone or in combination of two or more. Examples of the low molecular weight diol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, 2-methyl-1,3-propanediol, 3-methyl-1,5-pentanediol. 1,8-nonanediol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanedimethanol, 1,4-bis (β-hydroxyethoxybenzene) and the like. These can be used alone or as a mixture of two or more kinds.

A known method is used for producing the polyurethane elastomer which is a raw material of the polyurethane elastic fiber in the present invention. For example, a one-shot method in which a high-molecular diol, a low-molecular diol, and an organic diisocyanate are reacted together in a solvent or without a solvent, or a high-molecular diol and an organic diisocyanate are reacted in advance to form a prepolymer, and then the low-molecular diol is used as a solvent. A prepolymer method or the like in which the reaction is carried out under a solvent or without a solvent. From the viewpoint of cost, the melt polymerization method which is produced without a solvent is desirable.

The urethane group concentration of the thermoplastic polyurethane elastomer in the present invention must be 1500 or more. When the urethane group concentration is less than 1500, the stretchability of the obtained yarn is not sufficiently exhibited. The urethane group concentration referred to here is, for example, 4,4′-diphenylmethane diisocyanate (M
When abbreviated as DI) is used, it is expressed by the following equation. Urethane group concentration = {(MDI charge amount / total raw material charge amount) ÷
125} × 10 ⁶ (equivalent / 10 ⁶ g)

Further, the polyurethane fiber yarn of the present invention is required to have a heat setting rate of 75% or more in dry heat treatment at 140 ° C. × 1 minute in a 100% stretched state. When the heat setting rate is lower than 75%, problems such as width defects are likely to occur in the dimensional stability in the preset step before dyeing. The dry heat setting property referred to here is a value measured by the following method. A load of 1 mg per denier of polyurethane elastic fiber is applied and L0 is taken as the sample length. Then, the sample is stretched twice and subjected to dry heat treatment (140 ° C. × 1 minute) in the stretched state, relaxed at room temperature for 1 hour, and then measured for a length L1 under a load of 1 mg / d. calculate. Heat setting rate (%) = (L1−L0) / L0 × 100

When the polyurethane fiber is used as a stretchable composite yarn that forms the ground structure of a flat knitted fabric, it may be used alone, but it is easy to handle during knitting and in subsequent processes, process passability, etc. Considering the above, it is desirable to form a composite with a non-stretchable fiber. Examples of the method for forming a composite include a covering method in which the polyurethane fiber is arranged in the core and a non-stretchable fiber yarn is wound, a core yarn method using a spinning machine, a spinning spinning twisting method, or a mixed fiber method. As a result of various studies,
In the core yarn method and the fine spinning intertwisting method using a spinning machine, since the fibers to be coated are short fibers, it is difficult to form a stretchable yarn having a relatively thin thickness. The resulting increase in the thickness of the flat knitted fabric,
It was found that the characteristics of the material to be knitted, such as the change in softness, would be negated. The preferred composite method is a covering method using a synthetic filament, and a mixed fiber method using air. Among them, the covering method is uniform,
Excellent processability.

Although various kinds of synthetic filaments can be used, polyester, nylon and the like are easy to use because they have various brands. Above all, nylon is easy to adapt to other materials due to its softness. The thickness of the synthetic filament used in the present invention is 20 to 100d, preferably 30 to 70d. The thickness of polyurethane fiber is also 2
It is 0 to 100d, preferably 30 to 70d.

The present invention will be described below with reference to examples. However, the present invention is not limited to this embodiment.

EXAMPLE A spinning dope prepared by dissolving an acrylonitrile-based polymer of 90% acrylonitrile and 10% of methyl acrylate in a 48% aqueous solution of rodan soda was subjected to spinning, washing with water, stretching, crimping and heat treatment according to a conventional method, A raw material fiber having a denier of 0.8 × 70 mm was obtained. 3 for 1kg of this raw fiber
5 kg of 0% by weight of hydrous hydrazine was added, and a crosslinking treatment was performed at 98 ° C. for 3 hours. The amount of increase in nitrogen was 5.0%. After washing the crosslinked fiber with water, 5 kg of 3% by weight sodium hydroxide
Was added and the mixture was hydrolyzed at 90 ° C. for 2 hours. Then, it is treated with 1N HNO3 aqueous solution to convert the carboxyl group to H-type, washed with water, adjusted to pH 6.5 with 1N NaOH, added with 50 g of calcium chloride, and added with metal at 60 ° C for 2 hours. Salted. After thorough washing with water, dehydration, oil treatment and heat treatment (150 ° C.) to obtain crosslinked acrylic fibers. The characteristics of the obtained fiber are shown in Table 1.

In the knitted fabric knitted under such conditions, the thickness of the non-stretchable yarn is 2.5 times or more, more preferably 3 to 6 times as thick as the thickness of the polyurethane elastic composite yarn. Is preferred. This is because polyurethane, which is the main composition of polyurethane elastic composite yarns, has inferior light resistance compared to other materials, so stretchable yarns are unevenly distributed inside the fabric as much as possible and covered with non-stretchable yarns. Purpose not to expose
There is also the purpose of not giving the rubbery slimy texture of polyurethane to the surface of the fabric. Further, in the knitted fabric, the mixing ratio of the stretchable yarns is set by the strength of the stretching force due to the required performance, but it is preferably in the range of 5 to 20%. If it is less than 5%, the stretching force is too weak to exert the effect. On the other hand, if it is more than 20%, the drape property of the cloth is deteriorated and the cost is also increased, which is not preferable.

The moisture absorption rate of the crosslinked acrylate fiber is 27.
% Is about 3.8 times higher than cotton. The water retention rate of the fiber is as high as cotton. Further, the ammonia deodorizing rate is as high as 99% or more, which shows that it has a high deodorizing function for ammonia.

The resulting crosslinked acrylate fiber (1.8
dx37mm) acrylic fiber (Exlan: 1.5d
X38 mm) and combed cotton and the blending ratio was changed and blended, curd, kneading, spinning, and spinning were performed in accordance with a conventional method.
A count single yarn was spun. The twist coefficient was 3.5. As a comparative example, acrylic yarn, cut wool, combed cotton and polyester fiber (1.5d × 38mm) were similarly made into yarns, and after knitting a smooth knitted fabric with a 20-gauge double-sided knitting machine, dyeing and finishing were carried out by a conventional method. did. Table 2 shows the characteristic values of these knitted fabrics. It can be seen that the knitted fabric using 100% of the crosslinked acrylate fiber reproduces the same level of characteristics as the raw cotton fiber shown in Table 1. Especially, the water absorption length is about 1.
It can be seen that the drying time in touch is 3 times or more faster than cotton, and it is hydrophilic and dries quickly and has little wet feeling, although it is twice as large and the moisture absorption rate is as large as 3.8 times that of cotton. It can be seen that even the one obtained by mixing the crosslinked acrylate fiber and the other fiber retains the performance equal to or higher than the value equivalent to the mixed spinning rate.

These results and the spinnability in the spinning process,
Taking into consideration workability and the like, the blending ratios of crosslinked acrylate fiber and acrylic fiber were set to 30 and 70%, respectively, and a 2/52 yarn (metric count) was made for non-stretchable yarn. In order to dye the yarn into a dyed yarn, after prewinding (winding density 0.3 g / cm ³ ), scouring (60 ° C. × 10 minutes) and dyeing are performed by a conventional method using a high-pressure sealed package dyeing machine. (100 ° C. × 30 minutes). The dyeing recipe is a cationic dye,
The pH was set to 4 by using a cationic desensitizing agent and a leveling agent, and using acetic acid and sodium acetate. The flow rate was 0.5 l / kg / sec, and the liquid flow direction was in → out (one direction). After dyeing, slow cooling, dehydration, drying and rewinding were performed and used as a non-stretchable yarn.

On the other hand, the polymer diol is polybutylene adipate, the organic diisocyanate is 4,4'-diphenylmethane diisocyanate, and the low molecular diol is 1,4-.
A polyurethane elastomer polymerized with butanediol was spun into a 40 denier filament. The urethane group concentration was 1650. This is used as the core yarn of the stretchable composite yarn. Nylon false twisted yarn (Z → S) 70 denier 24 filament is used as the sheath yarn, the draft of the core yarn is 3.0, and the twist number of the sheath yarn is S500 times /
Stretchable composite yarn was made under the condition of meter.

The non-stretchable composite yarn and the stretchable composite yarn are set in a flat knitting machine (12 gauge), and the non-stretchable composite yarn is 5 ×.
No. 4 wide rib design, the stretchable composite yarn was a knitting fabric and knitted using a positive yarn feeder. After knitting, it was sewn on a sweater and subjected to steam treatment at 120 ° C. for 10 seconds using a mold for dimensional stabilization and patterning. Table 3 shows the heat setting rate of the elastic yarns used, the properties of the finished fabric, and other characteristics.

(Comparative Example 1) A comparative example was carried out except that a polyurethane elastic fiber of 20 denier 2 filaments which was dry-spun from polytetramethylene glycol, 4,4-diphenylmethane diisocyanate and ethylenediamine was used as the core yarn of the stretchable composite yarn. The knitted fabric for a sweater and the sweater were obtained by processing under the same method and the same conditions as in the example. Table 3 shows the heat setting rate of the elastic yarns used, the properties of the finished fabric, and other characteristics.

(Comparative Example 2) As the core yarn of the stretchable composite yarn, a polyurethane elastic fiber of 20 denier 2-filament dry-spun from polytetramethylene glycol, 4,4-diphenylmethane diisocyanate and ethylenediamine was used, and a form was used. Then, a knitted fabric for a sweater and a sweater were obtained by processing under the same method and the same conditions as in the example except that the steam treatment was performed at 130 ° C. for 10 seconds. Table 3 shows the heat setting rate of the elastic yarns used, the properties of the finished fabric, and other characteristics.

Since Comparative Example 1 has a low heat setting property, it has a large washing shrinkage ratio, is extremely inferior in dimensional stability, and has a heavy basis weight. In Comparative Example 2, no improvement in the setting rate was observed despite the increase in the setting temperature, and conversely, a slight yellowing of the acrylate fiber was observed and the elongation of the fiber due to heat increased. It becomes a "fat" and the appearance of the knitted fabric is deteriorated, and the feel is hard. The example retains various functions in a well-balanced manner, is excellent in dimensional stability, extensibility, texture, and the like, and is free from thermal yellowing.

The detailed description of the present invention and the measuring methods used in the examples will be described below. (1) PH buffering capacity (μeq / g) About 0.4 g of sufficiently dried test fiber is precisely weighed (X) g, 200 ml of water is added thereto, and then 0.1N hydrochloric acid aqueous solution or 0.1N caustic soda is added. The aqueous solution was dripped, and the consumption amount (Y) cc of the hydrochloric acid aqueous solution or caustic soda aqueous solution consumed until the pH reached 5.0 in the case of the hydrochloric acid aqueous solution and the pH 7.0 reached in the case of the caustic soda aqueous solution was calculated by the following formula: The buffering capacity against acid or alkali was calculated by. PH buffering capacity (μeq / g) = 1000Y / X

(2) Moisture absorption rate (%) About 5.0 g of sample fiber is dried with a hot air dryer at 105 ° C. for 16 hours, and the weight (W1) g is measured. Then sample 2
It is placed in a thermo-hygrostat adjusted to a relative humidity of 65% at 0 ° C. for 24 hours. The weight (W
2) Measure g. From the above results, the moisture absorption rate was calculated according to the following equation. Moisture absorption rate (%) = (W2-W1) / W1 × 100

(3) Antibacterial Test strain: Staphylococcus aureus Staphylococcus aureus
IFO 12732 Test method: The broth suspension of the test bacteria was added to the sterilized sample cloth by the method specified by the Textile Products Sanitary and Processing Council (SEK), and the mixture was incubated at 37 ° C for 18 hours in a closed container, followed by incubation. The number of bacteria is measured, and it is determined by the difference between the increase and decrease of the number B of the standard cloth and the number C of the sample with respect to the number A of inoculum. Increase / decrease value = logC-logA Increase / decrease value difference = (logB−logA) − (logC−log
gA)

(4) Anti-pill property JIS L 1076 Piling test method for woven and knitted fabrics was carried out according to the method A using an ICI type tester.

(5) Antistatic property JIS L 1094 The antistatic property of a woven fabric and a knitted fabric was tested according to the charging property test method.

The wicking length (cm) after 30 minutes from the start of measurement was determined based on the JIS L 1018 knitted fabric test method and the water absorption rate B method (Bayrec method).

(6) Drying time After the sample knitted fabric 10 × 10 cm was immersed in pure water for 1 hour, it was dehydrated for 2 minutes at 300 G rotation using a centrifugal dehydrator,
Tensilon / U installed in an atmosphere of 20 ° C and 65% RH
The sample was attached to a TM-11-20 type, the change in weight of the sample and the time were measured, and the drying time in touch was obtained.

(7) Water retention rate (%) 5 g of the sample fiber is immersed in pure water, left at 30 ± 5 ° C. for 3 hours, and then dehydrated by a centrifugal dehydrator at 1000 G for 3 minutes. The weight (W3) g of the dehydrated sample is measured. Next, the weight (W4) g of the sample dried to absolute dryness was obtained in a hot air dryer at 90 ° C., and the water retention rate (%) was calculated by the following formula. Water retention rate (%) = (W3−W4) / W4 × 100

(8) Ammonia deodorizing property 2 g of sample fiber was put in a Tedlar bag and sealed, and air was blown to 3
l inject. Next, 400 ppm of ammonia (W5) was injected into the Tedlar bag, and after standing at room temperature for 120 minutes, the ammonia concentration (W6) in the Tedlar bag was measured using the Kitagawa type detector tube. In addition, 400 ppm of ammonia was injected into a Tedlar bag containing no sample, and after 120 minutes, the ammonia concentration (W7) was measured and used as a blank test. From the above results, the ammonia deodorizing rate was calculated according to the following formula. Ammonia deodorization rate (%) = (W5-W6) / W7 × 10
0

(9) Moisture Absorption Rate Constant (k1) A knitted fabric of 5 × 20 cm is dried in a hot air dryer at 105 ° C. and then cooled to 20 ° C. in a desiccator. 20 ° C 65% RH
The knitted fabric is placed in the constant temperature and humidity chamber adjusted to, and the suction rate (W1) with respect to 120 minutes elapsed time is continuously measured. The knitted fabric is further placed in a thermo-hygrostat for 24 hours, and the saturated moisture absorption rate (We) is measured. Moisture absorption rate constant (k
1) is calculated. W1 = We (1-e-k1t) W1: Moisture absorption rate from absolute drying to time t We: 20 ° C. 65% RH saturated moisture absorption rate k1: Moisture absorption rate constant

(10) Moisture release rate constant (k2) A 5 × 20 cm knitted fabric was placed in a constant temperature and humidity chamber adjusted to 20 ° C. and 80% RH for 24 hours, and the saturated moisture absorption rate (Wb) at the same temperature and humidity was measured. taking measurement. The knitted fabric is at 20 ° C. and 30% RH
The sample is placed in a thermo-hygrostat adjusted to, and the moisture absorption rate (W2) with respect to 120 minutes elapsed time is measured. Furthermore, the knitted fabric is 20 ° C.
Saturated moisture absorption rate (Wa) at 20 ° C and 30% RH for 24 hours in a thermo-hygrostat adjusted to 30% RH.
To measure. The moisture release rate constant (k2) of the following rate equation is calculated. W2 = (Wa-Wb) (1-e-k2t) W2: Moisture absorption rate from Wb to time t Wa: Saturated moisture absorption rate at 20 ° C 30% RH Wb: Saturated moisture absorption rate at 20 ° C 80% RH k2: Moisture release rate Constant t: 0 to 30 minutes

(11) Elongation rate and recovery rate of knitted fabric Knitting was performed according to JIS L 1018 one-knit fabric test method. The elongation rate was measured using the method for measuring the elongation rate under constant load (load 1 kg) of JIS-L1018 method. JI
The elongation recovery rate was determined using the elongation elastic modulus A method (constant elongation method) of the S-L1018 method. 50% vertical elongation,
100% in the horizontal direction.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

[Table 3]

[0040]

EFFECT OF THE INVENTION The flat knitted fabric for a sweater of the present invention allows the sweater to have a PH buffering property, an antibacterial property, a deodorizing property, an anti-pill property, an antistatic property, a water absorbing property and a easiness of drying. In addition, the sweater ground structure is characterized by having elasticity, and a soft fit type flat knitted sweater can be provided by further mixing an ultrafine acrylic fiber.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuhiro Ooi 2-8 Dojimahama, Kita-ku, Osaka Toyobo Co., Ltd.

Claims (7)

[Claims] 1. In a flat knitted fabric forming a ground structure with a non-stretchable yarn and a polyurethane elastic composite yarn, the non-stretchable yarn is a yarn containing 20% or more of hygroscopic crosslinked acrylate fiber. A characteristic stretchable knitted fabric. 2. The stretchable flat knitted fabric according to claim 1, wherein the non-stretchable yarn is a spun yarn composed of a hygroscopic crosslinked acrylate fiber and an acrylic fiber. 3. The stretchable flat knitted fabric according to claim 1, wherein the polyurethane elastic composite yarn is a covering yarn in which a synthetic fiber multifilament is arranged in a sheath portion and polyurethane elastic fibers are arranged in a core portion. 4. A hygroscopic crosslinked acrylate fiber is introduced into the acrylic fiber by a hydrazine treatment to introduce a crosslinked structure so that the increase in nitrogen content is within the range of 1.0 to 8.0% by weight, and the residual amount is retained by hydrolysis. The amount of nitrile group present is 1.0 to 5.
The stretchable knitted fabric according to claim 1, which is an acrylate fiber in which a carboxyl group is introduced at 0 meq / g and 50 to 90 mol% of the carboxyl group is a metal salt type. 5. The polyurethane elastic fiber is a polyurethane filament yarn having a urethane group concentration of 1500 or more, which is obtained by spinning a polyurethane elastomer composed of a high molecular diol, an organic diisocyanate and a low molecular diol. The stretchable flat knitted fabric according to Item 3. 6. The polyurethane elastic fiber is 140 ° C. × 1
The stretchable flat knitted fabric according to claim 3, wherein the heat setting rate in a 100% stretched state is 75% or more. 7. The thickness of the non-stretchable yarn is 2.5 times or more the thickness of the polyurethane elastic composite yarn, and the proportion of the polyurethane elastic composite yarn is 5 to 20% in the knitted fabric. The stretchable flat knitted fabric according to claim 1, wherein