JP2011214160A - Bilayer-structured spun yarn, woven or knitted fabric, and method for producing woven or knitted fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bilayer-structured spun yarn, on making it a woven or knitted fabric, excellent in moisture-absorbing, heat-generating properties and warmth-keeping properties, capable of preventing the generation of static electricity and having a light weight property.SOLUTION: This bilayer-structured spun yarn is provided by satisfying the following (I) to (V) simultaneously. (I) The spun yarn has a sheath core structure in which a water soluble polyvinyl alcohol fiber 3A, and a solvent-spun cellulose fiber 1 and/or an acrylic fiber 2 are arranged as the core, and an acrylic fiber or the acrylic fiber and a solvent-spun cellulose fiber are arranged as the shear part, (II) the content of the water soluble polyvinyl alcohol fiber based on the whole amount of the core is 30 to 70 mass% and the content of the solvent-spun cellulose fiber and/or acrylic fiber based on the whole amount of the core is 70 to 30 mass%, (III) the content of the acrylic fiber based on the whole amount of the sheath is ≥50 mass%, (IV) the content of the solvent-spun cellulose fiber based on the whole amount of the spun yarn is 15 to 30 mass%, and (V) the mass ratio of (the core)/(the sheath) is (20/80) to (50/50).

Description

  The present invention relates to a two-layer spun yarn. In particular, the present invention relates to a double-layered spun yarn that is excellent in moisture absorption exothermic property and heat retaining property when it is made into a woven or knitted fabric, can prevent generation of static electricity, and has light weight. Furthermore, this invention relates to the manufacturing method of the woven / knitted fabric using the said two-layer structure spun yarn.

  In the field of clothing and the like, there has been a demand for a woven or knitted fabric that is lightweight and has high heat retention. Various studies have been made to meet such demands. For example, Patent Document 1 proposes manufacturing a woven or knitted fabric using a spun yarn using hollow fibers. However, in such a case, there is a problem that the hollow shape is easily broken in the process up to the spun yarn, and the performance is not sufficiently exhibited.

  Moreover, the multilayer structure twisted yarn which used melt | dissolution fibers, such as a polyvinyl alcohol-type fiber, for the core part, and its manufacturing method are proposed (for example, refer patent document 2, patent document 3, patent document 4). In such a case, dissolved fibers such as polyvinyl alcohol fibers are dissolved at the stage of producing the twisted yarn, and a hollow portion is formed. And after forming the hollow part, it is dyed and finished or processed into a woven or knitted fabric, but in such a processing stage, the hollow shape of the core part is easily damaged, and the hollow part is in the product stage. It was difficult to maintain up to. For this reason, there are cases where performance such as lightness and heat retention imparted by forming the hollow portion is not sufficiently exhibited.

  Furthermore, a two-layer structure spun yarn having a two-layer structure of a core layer and a sheath layer, in which a soluble fiber and a shrinkable fiber having a heat shrinkage rate of 10 to 40% are randomly arranged in the core portion has been proposed. (For example, refer to Patent Document 5). In this case, due to the performance of the shrinkable fiber, the hollow portion formed in the processing stage can be maintained up to the product stage, and performance such as lightness and heat retention due to the formation of the hollow portion is easily exhibited. However, depending on the performance of the fiber used for the sheath portion, sufficient lightness, heat retention, etc. may not be exhibited.

  In addition, for the purpose of obtaining clothing with better heat retention, clothing using polyester or acrylic moisture-absorbing exothermic fibers, and clothing using moisture-absorbing exothermic cellulose fibers in which a water-soluble vinyl polymer compound is introduced into cellulose. Has been proposed (see, for example, Patent Document 6 and Patent Document 7). However, in the case of Patent Document 6 and Patent Document 7, although it is excellent in moisture absorption exothermic property, even if the thermal insulation feeling is insufficient or even if the thermal insulation ability is temporarily exhibited, the heat dissipation from the human body over time. In some cases, the ability to stop was lacking.

  Further, a spun yarn containing hygroscopic exothermic fibers and hydrophobic synthetic fibers is known (see, for example, Patent Document 8). However, in this case, although it is excellent in moisture absorption exothermic property, there may be a feeling of contact cooling immediately after wearing, or it may be inferior in lightness and heat retention.

  Further, a woven fabric comprising a multilayer structure spun yarn in which a soluble fiber is contained in the core portion, and a hydrophobic synthetic fiber and a hygroscopic exothermic fiber are compounded in a ratio of 4: 1 to 1: 4 (mass ratio) in the sheath portion. A knitted fabric has been proposed (see, for example, Patent Document 9). However, in this case, the mass ratio of the soluble fiber used for the core portion to the entire core portion is not defined, and the mass ratio of the core and the sheath is not limited. Therefore, depending on the mass ratio of the soluble fiber in the core part and the mass ratio of the core and the sheath, it is difficult to form the hollow part, and even if it is formed, the hollow part is crushed, sufficient lightness and heat retention, etc. May not be demonstrated.

  Conventionally, clothing materials for autumn and winter clothing have a problem that wearing comfort is greatly impaired if the antistatic property is poor. However, none of the above-mentioned patent documents discusses the problem with respect to antistatic properties.

Japanese Patent Laid-Open No. 7-18535 Japanese Patent Laid-Open No. 9-31781 JP-A-9-59839 JP-A-9-302545 JP 2002-138336 A Japanese Patent Publication No. 7-59762 Japanese Patent No. 2898623 JP 2003-227043 A JP 2005-068596 A

  The present invention has been made in view of the above situation, and provides a double-layered spun yarn that is excellent in moisture absorption heat generation and heat retention, can suppress the generation of static electricity, and has lightness when made into a woven or knitted fabric. It is intended to do.

The inventors of the present invention have arrived at the present invention as a result of intensive studies in order to solve such problems.
That is, the gist of the present invention is as follows.
(1) A two-layer structure spun yarn characterized by satisfying the following (I), (II), (III), (IV) and (V) simultaneously.
(I) A water-soluble polyvinyl alcohol fiber, a solvent-spun cellulose fiber and / or an acrylic fiber are arranged in the core, and an acrylic fiber is arranged in the sheath, or the acrylic fiber and the solvent It has a core-sheath structure in which spun cellulosic fibers are arranged.
(II) The content of water-soluble polyvinyl alcohol fiber relative to the total amount of the core is 30 to 70% by mass, and the content of solvent-spun cellulose fiber and / or acrylic fiber relative to the total amount of the core is 70 to 30% by mass. is there.
(III) The content ratio of the acrylic fiber with respect to the total amount of the sheath part is 50% by mass or more.
(IV) The content ratio of the solvent-spun cellulose-based fiber to the entire spun yarn is 15 to 30% by mass.
(V) Mass ratio of core part and sheath part is core part / sheath part = 20/80 to 50/50.
(2) A woven or knitted fabric composed of spun yarn characterized by simultaneously satisfying the following (VI), (VII), (VIII), (IX) and (X).
(VI) A hollow portion is present in the core, solvent-spun cellulose-based fibers and / or acrylic fibers are disposed, and acrylic fibers are disposed in the sheath, or acrylic fibers and solvent-spun cellulose. It has a core-sheath structure in which system fibers are arranged.
(VII) The content ratio of the solvent-spun cellulose fiber and / or acrylic fiber with respect to the total amount of the core is 70 to 30% by mass.
(VIII) The content ratio of the acrylic fiber with respect to the total amount of the sheath part is 50% by mass or more.
(IX) The content ratio of the solvent-spun cellulose-based fiber with respect to the entire spun yarn is 16 to 46% by mass.
(X) The mass ratio of the core part to the sheath part is core part / sheath part = 7/93 to 41/59.
(3) A method for producing a woven or knitted fabric using the two-layer structure spun yarn according to (1), wherein after producing the woven or knitted fabric, the water-soluble polyvinyl alcohol fiber in the core is dissolved, A method for producing a woven or knitted fabric, characterized in that the spun yarn has a hollow portion formed in the core of a double-layered spun yarn.

  According to the present invention, it is possible to obtain a double-layered spun yarn suitable for woven or knitted fabrics for clothing and the like, which is excellent in moisture absorption exothermic property, hardly generates static electricity, and has lightness and heat retention. Furthermore, the woven or knitted fabric obtained by using this two-layer structure spun yarn is less likely to be crushed in the hollow portion, and is excellent in lightness and heat retention. Furthermore, the woven or knitted fabric obtained in the present invention is suitably used as a sewn product, for example, clothing such as underwear, pajamas, blankets, scarves, mufflers, hats, gloves, socks, and cushions.

It is the schematic which shows an example of the cross-sectional shape of the two-layer structure spun yarn of this invention. It is a schematic side view which shows an example of the roving machine for manufacturing the roving of the two-layer structure spun yarn of this invention. It is the schematic which shows an example of the cross-sectional shape of the spun yarn which has the hollow part which comprises the woven / knitted fabric of this invention.

Hereinafter, the present invention will be described in detail.
The double-layer structure spun yarn of the present invention has a cross-sectional shape as shown in FIG. In FIG. 1, 1 is a solvent-spun cellulose fiber, 2 is an acrylic fiber, and 3A is a water-soluble polyvinyl alcohol fiber. As shown in FIG. 1, a fiber group in which water-soluble polyvinyl alcohol-based fibers, solvent-spun cellulose-based fibers, and / or acrylic fibers are arranged is formed in the core portion. A fiber group in which solvent-spun cellulosic fibers and / or acrylic fibers are arranged is formed in the sheath portion.

  The water-soluble polyvinyl alcohol fiber used in the present invention is mainly composed of polyvinyl alcohol. Polyvinyl alcohol has hydrophilicity and is soluble in warm water. The water-soluble polyvinyl alcohol-based fiber is removed in a dissolving step described later after a woven or knitted fabric is produced using a two-layer structure spun yarn. By passing through such a process, since it becomes a spun yarn in which a hollow portion is formed, excellent lightness and heat retention can be imparted to the woven or knitted fabric. In the present invention, “having polyvinyl alcohol as a main component” means that the content of polyvinyl alcohol is 95% by mass or more based on the entire water-soluble polyvinyl alcohol fiber.

  The water-soluble polyvinyl alcohol fiber may be a long fiber or a short fiber, but is preferably a short fiber having a fiber length of 30 to 60 mm. By setting the fiber length in such a range, the constituent fibers are intertwined in the vicinity of the boundary between the core part and the sheath part, and an effect is obtained that even if the knitted or knitted fabric is subjected to an external force, misalignment or peeling is less likely to occur. The Moreover, since the texture of the woven or knitted fabric can be improved and the gaps between the fibers can be increased, the heat retention is further improved.

  The acrylic fiber used in the present invention is a synthetic fiber mainly composed of acrylonitrile and has hydrophobicity. The polyacrylic fiber has a large shrinkage rate and is excellent in bulkiness compared with other hydrophobic synthetic fibers, and thus can greatly contribute to improvement of heat retention. In the present invention, “having acrylonitrile as a main component” means that the content of acrylonitrile is 95% by mass or more based on the entire acrylic fiber.

  When the acrylic fiber is used for any of the core and the sheath, the single yarn fineness is preferably 0.1 to 1.6 dtex, and more preferably 0.4 to 1.3 dtex. When the single yarn fineness is 1.6 dtex or less, the gap diameter between the single fibers becomes small, the airflow resistance becomes high, the dead air increases, the ability to prevent heat dissipation is improved, and hydrophilicity is increased. The effect of hygroscopic heat generation of the conductive fiber can be maintained for a long time, and the two-layer structure of the two-layer structure spun yarn becomes high. That is, when the single yarn fineness exceeds 1.6 dtex, the diameter of the gap between the single fibers becomes too large, and it becomes easy to dissipate heat and the texture becomes hard, and further, the two layers of the two-layer structure spun yarn The structure may be deteriorated. In addition, when the single yarn fineness is less than 0.1 dtex, since the bending rigidity of the single fiber is low, a substantial amount of void between the single fibers is reduced by applying pressure during wearing, so that the heat retaining property is reduced. There may be a problem of lowering.

  The acrylic fibers may be long fibers or short fibers, but are preferably short fibers having a fiber length of 30 to 60 mm. By setting the fiber length in such a range, the constituent fibers are intertwined in the vicinity of the boundary between the core part and the sheath part, and an effect is obtained that even if the knitted or knitted fabric is subjected to an external force, misalignment or peeling is less likely to occur. The Moreover, since the texture of the woven or knitted fabric can be improved and the gaps between the fibers can be increased, the heat retention is further improved.

  The cross-sectional shape of the acrylic fiber is not particularly limited, but a round cross-sectional shape is preferable in consideration of the spinnability and the shape of the spinneret. Moreover, it is preferable to use a hollow fiber as an acrylic fiber for the purpose of imparting more excellent lightness and heat retention.

The acrylic fiber may contain components other than acrylonitrile as long as the effects of the present invention are not impaired.
The solvent-spun cellulose fiber used in the present invention is obtained by dissolving cellulose itself in a solvent and solution spinning, and is a fiber having excellent moisture absorption exothermic property and antistatic property. In addition, since a process such as derivatization is not performed, the degree of polymerization of cellulose molecules is small, and the strength is excellent.

  The single yarn fineness of the solvent-spun cellulosic fiber is preferably 0.6 to 2.2 dtex, more preferably 0.7 to 1.6 dtex, regardless of whether the single yarn fineness of the solvent-spun cellulose fiber is used for the core part or the sheath part. preferable. When the single yarn fineness is 2.2 dtex or less, the surface area of the fiber increases, so that the response of moisture absorption heat generation becomes faster, and the moisture absorption heat generation temperature rises when it is put to practical use. There is an advantage. When the single yarn fineness exceeds 2.2 dtex, not only the moisture absorption exothermic property decreases, but also the texture becomes hard and the two-layer structure of the two-layer structure spun yarn tends to deteriorate. Further, when the single yarn fineness is less than 0.6 dtex, since the bending rigidity of the single fiber is low, the substantial amount of voids between the single fibers is reduced by applying pressure during wearing, so that the heat retaining property is reduced. There may be a problem of lowering. That is, when the single yarn fineness is in the above range, there are advantages that the touch is good, the moisture absorption exothermic property is excellent, and a two-layer structure is easily formed in the spun yarn.

  Solvent-spun cellulosic fibers may be long fibers or short fibers, but from the point of improving the texture of the woven or knitted fabric obtained and preventing the gap between the core and the sheath and peeling, Short fibers having a fiber length of 30 to 60 mm are preferred.

  The cross-sectional shape of the solvent-spun cellulose-based fiber is not particularly limited, but a round cross-sectional shape is preferable in consideration of the spinnability and the shape of the spinneret. Moreover, it is preferable to use a hollow fiber as the solvent-spun cellulose-based fiber for the purpose of imparting more excellent lightness and heat retention.

  In the two-layer structure spun yarn of the present invention, the mass ratio of the core part to the sheath part needs to be core part / sheath part = 20/80 to 50/50, and the core part / sheath part = 35 / It is preferable that it is 65-45 / 55. If the ratio of the core part / sheath part is less than 20/80, there arises a problem that the core part or the hollow part is crushed. Moreover, when the ratio of the core part / sheath part exceeds 50/50, there arises a problem that the covering property in which the sheath part wraps the core part is deteriorated.

  In the two-layer structure spun yarn of the present invention, the ratio of the water-soluble polyvinyl alcohol fiber to the total amount of the core is required to be 30 to 70% by mass, and preferably 45 to 55% by mass. When the content is less than 30% by mass, there is a problem that the hollowness is reduced and the heat retention is deteriorated. On the other hand, when the content ratio exceeds 70% by mass, hollow crushing during dyeing tends to occur, and there is a problem that it is difficult to obtain strength sufficient for practical use.

  In the two-layer structure spun yarn of the present invention, it is necessary that the content ratio of the solvent-spun cellulose-based fiber and / or acrylic fiber with respect to the total amount of the core is 70 to 30% by mass, and is 55 to 45% by mass. It is preferable. If the content is less than 30% by mass, there is a problem that hollow crushing is likely to occur during dyeing. On the other hand, when the content ratio exceeds 70% by mass, there is a problem that the hollowness is decreased and the heat retention is deteriorated. In the case where both solvent-spun cellulose fiber and acrylic fiber are used for the core, the total content of both needs to satisfy the above range.

  In the two-layer structure spun yarn of the present invention, the content of acrylic fiber with respect to the total amount of the sheath portion needs to be 50% by mass or more, preferably 80% by mass or more, and most preferably 100%. When this content is less than 50% by mass, desired heat retention cannot be imparted to the woven or knitted fabric.

  In the two-layer structure spun yarn of the present invention, the content of the solvent-spun cellulose-based fiber with respect to the entire spun yarn needs to be 15 to 30% by mass, and preferably 16 to 26% by mass. If the content is less than 15% by mass, there is a problem that the hygroscopic exothermic property and antistatic property of the woven or knitted fabric are reduced. On the other hand, when the content ratio exceeds 30% by mass, the heat retention of the woven or knitted fabric is reduced.

  In addition, each content rate of the fiber which comprises said core part and sheath part can be calculated | required by remove | dividing the mass of each constituent fiber by the whole mass.

  Although the manufacturing method of the double-layer structure spun yarn of this invention is not specifically limited, The example is demonstrated using FIG.

  First, water-soluble polyvinyl alcohol fiber, solvent-spun cellulose fiber, and acrylic fiber are obtained by ordinary spinning means. The obtained water-soluble polyvinyl alcohol-based fiber, solvent-spun cellulosic fiber and / or acrylic fiber sliver S1, and acrylic fiber, or acrylic fiber and solvent-spun cellulose fiber The upstream sliver S2 is supplied in parallel to the roving machine. Each sliver is sent out in the process of passing through the apron 5 and the second roller 6 after passing through the back roller 4, and then S1 is sent out to the separately provided front roller 7A and S2 is sent out to 7B. Here, by making the surface speed of the front roller 7A the same as the surface speed of the second roller 6 and making the surface speed of the front roller 7B faster than the surface speed of the second roller 6, the sliver S2 is faster than the sliver S1, that is, the speed is low. It is made to run with tension, and it is set as the fiber bundle 8 while winding S2 around S1. By winding the fiber bundle 8 around the flyer head 9, a roving yarn can be obtained and this can be spun to obtain a double-layered spun yarn.

  In the present invention, after obtaining the double-layered spun yarn, it may be pre-set. By doing in this way, since the shape of the water-soluble polyvinyl alcohol fiber is fixed by the heat of the preset, the water-soluble polyvinyl alcohol fiber is removed and a hollow portion is formed in the below-described dissolution step Moreover, since excellent shape stability is imparted to the hollow portion, it is preferable. The reason is that, as the shape stability of the hollow portion is improved, the hollow portion is less likely to be crushed by washing or ironing after the obtained knitted or knitted fabric becomes a garment.

  The presetting is preferably performed in a state in which a position to be a hollow portion is secured. In other words, by performing the presetting before the removal of the water-soluble polyvinyl alcohol fiber, it is possible to fix the shape of the acrylic fiber while allowing the polyvinyl alcohol fiber to absorb the stress accompanying the thermal shrinkage of the acrylic fiber. Become.

  The presetting conditions may be appropriately set in consideration of the type of acrylic fiber. For example, it is preferable that the temperature is 160 to 190 ° C. and the processing time is 30 to 120 seconds. If the above temperature is too low or the treatment time is too short, the amount of heat is insufficient, and the acrylic fiber layer may not be sufficiently fixed. On the other hand, if the temperature is too high or the treatment time is too long, the amount of heat may be so great that the acrylic fiber or solvent-spun cellulose fiber may turn yellow or the texture of the woven or knitted fabric may be cured.

Next, the manufacturing method of the woven or knitted fabric of the present invention will be described below.
First, the two-layer structure spun yarn of the present invention is prepared in advance. A woven or knitted fabric is produced by the conventional method using the double-layer structure spun yarn. Thereafter, by scouring the obtained woven or knitted fabric, the water-soluble polyvinyl alcohol fiber is dissolved (dissolving step), and the woven or knitted fabric comprising a spun yarn having a hollow portion formed in the core as shown in FIG. It can be. In addition, in FIG. 3, it is preferable to perform a melt | dissolution process on the conditions of 40 degreeC x 30 minutes in a scouring process from a viewpoint of a standard dyeing process. In FIG. 3, 1 indicates a solvent-spun cellulose fiber, 2 indicates an acrylic fiber, and 3B indicates a hollow portion.

  In addition, when a woven or knitted fabric is directly manufactured using a hollow spun yarn, the hollow shape of the core part is easily damaged, the shape stability of the hollow part is inferior, and performance such as lightness and heat retention cannot be sufficiently expressed. There is also a problem that it is disadvantageous in terms of manufacturing cost.

  By forming the hollow portion in the spun yarn, it becomes possible to impart excellent lightness and heat retention to the woven or knitted fabric. In the present invention, as described above, after forming a woven or knitted fabric, polyvinyl alcohol fibers are dissolved from the double-layered spun yarn. As a result, in the woven or knitted fabric, the content of the solvent-spun cellulosic fiber with respect to the entire spun yarn is 16 to 46% by mass. Similarly, the mass ratio of the core portion to the sheath portion in the spun yarn is also core portion / sheath portion = 7/93 to 41/59.

  Further, the hollow ratio of the spun yarn is preferably 10 to 25%, more preferably 12 to 22%. In addition, the hollow rate here refers to the area ratio which this hollow part accounts in the spun yarn cross section containing a hollow part. If the hollow ratio is less than 10%, the total amount of air stored in the spun yarn tends to decrease, and the heat retention of the woven or knitted fabric tends to decrease, such being undesirable. On the other hand, if the hollow ratio exceeds 25%, the hollow portion tends to be easily crushed by external pressure, which is not preferable.

  The woven or knitted fabric of the present invention may be dyed by an ordinary method as long as the effects of the present invention are not impaired.

  Other yarns such as antistatic fibers may be used in the woven or knitted fabric of the present invention within a range not impairing the effects of the present invention. However, the mass ratio of the hollow spun yarn in the woven or knitted fabric is preferably 60% by mass or more, and more preferably 70% by mass or more in order to fully exhibit the effects of the present invention. The type of the other yarn used is not particularly limited, but the composite form of the other yarn in the woven or knitted fabric is not particularly limited in addition to the arrangement, the mixed knitting with the two-layer structure spun yarn other than the knitted and knitted fabric, and the combined twist. It is not something. Further, the method of weaving / knitting is not particularly limited.

  In addition, cotton, silk, hair, polyester fiber, nylon fiber, or the like may be used for the woven or knitted fabric of the present invention as long as the effects of the present invention are not impaired.

  The thickness of the woven or knitted fabric of the present invention is not particularly limited, but is preferably 0.4 to 0.8 mm from the viewpoint of a balance between heat retention and light weight.

The basis weight of the woven or knitted fabric of the present invention is not particularly limited, but is preferably 100 to 160 g / m ² from the viewpoint of a balance between heat retention and light weight.

  The woven or knitted fabric obtained in this way is excellent in moisture absorption exothermic property, hardly generates static electricity, has lightness and heat retention, and is therefore suitably used for various clothing applications.

Next, the present invention will be specifically described with reference to examples.
In addition, evaluation in an Example was performed with the following measuring methods.
(1) Hollow rate of spun yarn Hollow spun yarn was collected from the woven and knitted fabrics obtained in Examples and Comparative Examples, and the cross-sectional shape of the spun yarn was analyzed with an electron microscope (trade name “JSM-531, manufactured by JEOL Datum Co., Ltd.). ”(Magnification: 500 ×), the photograph was traced, a portion corresponding to the entire spun yarn including the hollow portion was cut out, and the area (A) was measured. After the measurement, a portion corresponding to the hollow portion was cut out and the area (B) was measured. This operation was performed for 10 spun yarns, the average values of A and B were calculated, and these values were substituted into the following equation to obtain the hollowness of the spun yarn.
Hollow ratio (%) = (B / A) × 100

(2) Insulation rate of woven or knitted fabric (insulation)
Heat plate (trade name “Thermo Lab II Type: KES-F7”, manufactured by Kato Tech Co., Ltd.) that maintains a constant temperature of 30 ° C. reaches an equilibrium state in a constant temperature and humidity device set at a temperature of 20 ° C. and a humidity of 65% RH. The amount of heat consumed was measured as Blank. Next, a sample (size: 17 cm × 17 cm) was placed on the hot plate, and the amount of heat consumed when the equilibrium state was reached was measured. The heat retention rate was calculated by the following formula. The higher the heat retention rate, the more difficult it is to dissipate heat, and it can be said that the heat retention is excellent.
Thermal insulation rate (%) = {[Blank measurement value (w) −Sample heat consumption (w)] / Blank measurement value (w)} × 100
In the above formula, the heat consumption was determined by the following formula.
Heat consumption [w / (m ² · ° C.)] = Measured value (w) / [heat plate area (m ² ) × temperature difference (10 ° C.)]

(3) Hygroscopic exothermic property of woven or knitted fabric A sample (size: 15 cm x 15 cm) is affixed to a polystyrene foam plate in an environmental chamber set at a temperature of 20 ° C and a humidity of 65% RH, and this is used as a sample set. For 12 hours or more. Next, this sample set was placed in a desiccator containing silica gel, and the desiccator was left in an environmental chamber at a temperature of 30 ° C. and a humidity of 90% RH for 4 hours or more to completely dry the sample. Thereafter, the sample set is taken out from the desiccator, and image recording is started using a thermograph (trade name “Thermo Tracer TH7102MX” manufactured by NEC Saneisha Co., Ltd.) in an environment room at a temperature of 30 ° C. and a humidity of 90% RH. The sample surface temperature was measured every second for 5 minutes after placing the sample, and the sample surface temperature at the maximum heat generation was extracted. It can be said that the higher the sample surface temperature, the better the hygroscopic heat generation.

(4) Frictional withstand voltage and half-life (antistatic property) of woven and knitted fabrics
It measured according to JIS-L-1094.

(5) The thickness and the basis weight of the woven / knitted fabric were measured according to JIS-L-1018.

(6) Lightness As an evaluation of lightness, the basis weight per unit thickness was obtained from the following formula.
Unit weight per unit thickness [(g / m ² ) / mm] = [Weight (g / m ² ) / Thickness (mm)] × 100

Example 1
Water-soluble polyvinyl alcohol fiber (Kuraray Co., Ltd., trade name “Kuraron K-2”) (water dissolution temperature: 40 ° C., single yarn fineness: 1.7 dtex, fiber length: 38 mm), acrylic fiber (Mitsubishi Rayon Co., Ltd.) , A trade name “Bonnell”) (single yarn fineness: 0.8 dtex, fiber length: 38 mm), a sliver (S1: fiber sliver constituting the core portion) blended at 50:50 (mass ratio). Furthermore, acrylic fiber (Made by Mitsubishi Rayon, trade name “Bonnell”) (single yarn fineness: 0.8 dtex, fiber length: 38 mm) and solvent-spun cellulose fiber (trade name “Sylph”, produced by Unitika Trading) ( A sliver (S2: sliver of fibers constituting the sheath) obtained by blending single yarn fineness: 0.9 dtex, fiber length: 38 mm) at 73:27 (mass ratio) was obtained. In addition, the mass ratio per unit length of these two types of sliver was S1 / S2 = 4/6.

Next, the two types of sliver were supplied to a roving machine having a structure as shown in FIG. 2 so that S1 was a sliver made of core component fibers and S2 was a sliver made of sheath component fibers. Here, the surface speed of the front roller 7A and the surface speed of the second roller 6 were the same. The surface speed of the front roller 7B was set to 1.03 times the surface speed of the second roller 6. A sliver S2 is wound around the sliver S1 to form a fiber bundle 8 and wound around a roving wood tube through a flyer 9, and the roving yarn mass is 180 gr / 30 yd (1 gr: 0.065 g, 1 yd: 0.9144 m), the number of twists It wound up as a 1.06T / 2.54cm roving. This roving was finely spun to obtain a double-layered spun yarn having a yarn count of 50 (English cotton count) and a twist number of 27.0 T / 2.54 cm.
In the obtained spun yarn, the content ratio of the solvent-spun cellulose-based fiber was 16% by mass with respect to the entire spun yarn.

  Using this spun yarn, a smooth structure was knitted by a double gauge knitting machine having a hook diameter of 33 in (1 in = 2.54 cm) and 28 gauge. The obtained raw machine was scoured at 40 ° C. for 30 minutes to remove the water-soluble polyvinyl alcohol fiber disposed in the core of the spun yarn. Then, after passing through a dyeing process at 100 ° C. for 30 minutes using a cationic dye, final setting was performed at 160 ° C. for 2 minutes with a pin tenter to obtain a woven or knitted fabric of the present invention. The spun yarn contained in the woven or knitted fabric had a hollow portion in the core portion and had a cross-sectional shape as shown in FIG.

  In the spun yarn in the woven or knitted fabric, the content ratio of the solvent-spun cellulose fiber to the whole spun yarn was 20% by mass, and the mass ratio of the core part to the sheath part was core / sheath part = 25/75. Moreover, the hollow ratio was 20%.

(Example 2)
Water-soluble polyvinyl alcohol fiber (Kuraray Co., Ltd., trade name “Kuraron K-2”) (water dissolution temperature: 40 ° C., single yarn fineness: 1.7 dtex, fiber length: 38 mm), solvent-spun cellulose fiber (Unitika Trading) A sliver (S1) obtained by blending 50:50 (mass ratio) with a product name of “Sylph” (manufactured by company) (single yarn fineness: 0.9 dtex, fiber length: 38 mm) was obtained. Subsequently, a sliver (S2) was obtained with 100% acrylic fiber (manufactured by Mitsubishi Rayon Co., Ltd., trade name “Bonnel”) (single yarn fineness: 0.8 dtex, fiber length: 38 mm). In addition, the mass ratio per unit length of these two types of sliver was S1 / S2 = 4/6. Using the above two types of sliver, in the same manner as in Example 1, a roving yarn was obtained and finely spun, and a two-layer structure spinning with 60 count (English cotton count) and 30.39 T / 2.54 cm twist I got a thread.
In the obtained spun yarn, the content ratio of solvent-spun cellulose-based fibers was 20% by mass with respect to the entire spun yarn.
Next, using this spun yarn, a one-bag tissue was knitted with a 17-inch, 18-gauge milling knitting machine using this spun yarn, and water-soluble polyvinyl alcohol was removed and dyeing was performed in the same manner as in Example 1. A woven or knitted fabric of Example 2 was obtained.

  In the spun yarn in the woven or knitted fabric, the content ratio of the solvent-spun cellulose-based fiber to the whole spun yarn was 25% by mass, and the mass ratio of the core part to the sheath part was core part / sheath part = 25/75. Moreover, the hollow ratio was 20%.

(Comparative Example 1)
Instead of using a double-layered spun yarn, ordinary acrylic fiber (manufactured by Toray Industries, Inc.) (single yarn fineness: 1.0 dtex, fiber length: 38 mm), except that a 50th yarn (English cotton count) was used. In the same manner as in Example 1, a woven or knitted fabric of Comparative Example 1 was obtained.

(Comparative Example 2)
Except for using a normal acrylic fiber (manufactured by Toray Industries, Inc.) (single yarn fineness: 1.0 dtex, fiber length: 38 mm), 60th yarn (English cotton yarn), instead of the two-layer structure yarn. In the same manner as in Example 2, a woven or knitted fabric of Comparative Example 2 was obtained.

(Comparative Example 3)
Normal acrylic fiber (manufactured by Toray Industries, Inc.) (single yarn fineness: 1.0 dtex, fiber length: 38 mm) and solvent-spun cellulose fiber (manufactured by Unitika Trading, trade name “Sylph”) (0.9 dtex, fiber length: 38 mm) was blended at a ratio of 6: 4 to obtain a 50th (English cotton count) spun yarn, and a woven or knitted fabric of Comparative Example 3 was obtained in the same manner as in Example 1.

(Comparative Example 4)
Normal acrylic fiber (manufactured by Toray Industries, Inc.) (single yarn fineness: 1.0 dtex, fiber length: 38 mm) and solvent-spun cellulose fiber (manufactured by Unitika Trading, trade name “Sylph”) (0.9 dtex, fiber length: 38 mm) was blended at a ratio of 6: 4 to obtain a 60th (English cotton count) spun yarn, and a woven or knitted fabric of Comparative Example 4 was obtained in the same manner as in Example 2.

  Table 1 shows the evaluation results of the spun yarns and woven and knitted fabrics obtained in the examples and comparative examples.

  As is clear from Table 1, the knitted and knitted fabrics obtained in Example 1 and Example 2 were excellent in heat retention, moisture absorption exothermic property and antistatic property, and were lightweight. When Example 1 and Example 2 are compared, the knitted or knitted fabric of Example 1 is higher in both thickness and basis weight than in Example 2, and thus has better results in heat retention.

The woven and knitted fabrics obtained in Comparative Example 1 and Comparative Example 2 were inferior in antistatic properties because they were composed only of acrylic fibers.
Moreover, when Example 1 and Comparative Example 1 were compared, in Comparative Example 1, since solvent-spun cellulose-based fibers were not used, the results were inferior in hygroscopic heat generation. The same can be said when Example 2 and Comparative Example 2 are compared.

  Furthermore, when Example 1 and Comparative Example 3 were compared, in Comparative Example 3, since there was no hollow portion in the spun yarn, the heat retention was poor. The same can be said when Example 2 and Comparative Example 4 are compared.

  Furthermore, when Example 1 was compared with Comparative Example 1 and Comparative Example 3, Example 1 was superior in lightness. The same can be said when Example 2 is compared with Comparative Examples 2 and 4.

  The two-layer structure spun yarn of the present invention can be suitably used for knitted fabrics, woven fabrics and the like. The obtained woven or knitted fabric is used as a sewn product, for example, clothing such as underwear, pajamas, blankets, scarves, scarves, hats, gloves, socks, cushions, etc. It is effective to protect.

DESCRIPTION OF SYMBOLS 1 Solvent spinning cellulose fiber 2 Acrylic fiber 3A Water-soluble polyvinyl alcohol fiber 3B Hollow part 4 Back roller 5 Apron 6 Second roller 7A, 7B Front roller 8 Fiber bundle 9 Flyer head S1 Sliver S2 which consists of a core component fiber Sheath component Sliver made of fiber

Claims (3)

A two-layer structure spun yarn characterized by satisfying the following (I), (II), (III), (IV) and (V) simultaneously.
(I) A water-soluble polyvinyl alcohol fiber, a solvent-spun cellulose fiber and / or an acrylic fiber are arranged in the core, and an acrylic fiber is arranged in the sheath, or the acrylic fiber and the solvent It has a core-sheath structure in which spun cellulosic fibers are arranged.
(II) The content of water-soluble polyvinyl alcohol fiber relative to the total amount of the core is 30 to 70% by mass, and the content of solvent-spun cellulose fiber and / or acrylic fiber relative to the total amount of the core is 70 to 30% by mass. is there.
(III) The content ratio of the acrylic fiber with respect to the total amount of the sheath part is 50% by mass or more.
(IV) The content ratio of the solvent-spun cellulose-based fiber to the entire spun yarn is 15 to 30% by mass.
(V) Mass ratio of core part and sheath part is core part / sheath part = 20/80 to 50/50. A woven or knitted fabric composed of spun yarns characterized by satisfying the following (VI), (VII), (VIII), (IX) and (X) simultaneously.
(VI) A hollow portion is present in the core, solvent-spun cellulose-based fibers and / or acrylic fibers are disposed, and acrylic fibers are disposed in the sheath, or acrylic fibers and solvent-spun cellulose. It has a core-sheath structure in which system fibers are arranged.
(VII) The content ratio of the solvent-spun cellulose fiber and / or acrylic fiber with respect to the total amount of the core is 70 to 30% by mass.
(VIII) The content ratio of the acrylic fiber with respect to the total amount of the sheath part is 50% by mass or more.
(IX) The content ratio of the solvent-spun cellulose-based fiber with respect to the entire spun yarn is 16 to 46% by mass.
(X) The mass ratio of the core part to the sheath part is core part / sheath part = 7/93 to 41/59.   A method for producing a woven or knitted fabric using the double-layer structure spun yarn according to claim 1, wherein the water-soluble polyvinyl alcohol fiber in the core is dissolved after the woven or knitted fabric is produced. A method for producing a woven or knitted fabric, wherein the spun yarn has a hollow portion formed in a core portion of the spun yarn.

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