TWI615519B - Knitwear and clothes - Google Patents

Abstract

A multi-angled hollow polyester multifilament. The cross-sectional shape of a single fiber is quadrangular to octagonal, and it has a single hollow portion. A single fiber having a regular fiber cross-section. Because the anti-transparent effect is obtained by the refraction of light on the fiber surface, and the densest filling can be achieved, the heat-shielding property is improved, and by having a hollow portion, not only the fiber becomes lightweight, but also if the hollow portion is circular, Refraction of light becomes random, and the anti-transparency effect is further exerted. Even as a processed yarn, when it is made into a knitted fabric, it exhibits significant weight reduction, excellent heat shielding property, light shielding property, and transparency prevention.

Description

Knitwear and clothing

The present invention relates to a fiber bundle suitable for a knitted fabric excellent in heat-shielding property, light-shielding property, and transparency even in a light color, and a false-twisted yarn, knitted fabric, and clothing containing the same.

Polyester fiber has excellent gloss and coolness, and hollow fiber of polyester fiber is excellent in lightness, so it is used for knitting for clothing. Furthermore, it is also disclosed in Japanese Patent Laid-Open No. 4 -257314 (Patent Document 1) or Japanese Patent Laid-Open No. 9-157958 (Patent Document 2) proposes a polygonal cross-section hollow polyester fiber in which a polygonal cross-section fiber and a hollow fiber are combined.

However, the polygonal cross section hollow polyester fiber, which is a morphological combination of a polygonal cross section fiber and a hollow fiber, has a high polygonal shape and is close to a circular cross section. Therefore, the characteristics of the polygonal cross section fiber cannot be fully utilized.

Conventionally, in the fibers of curtains or clothing used for blocking the radiant heat from sunlight, for example, Japanese Patent Laid-Open No. 11-81048 (Patent Document 3) or Japanese Patent Laid-Open No. 9-137345 ( Patent Document 4) and the like are known as fibers in which white pigments such as titanium oxide, talc, and barium sulfate, or inorganic fine particles such as carbon black and aluminum powder are dispersed in fibers.

Furthermore, according to, for example, Japanese Patent Laid-Open No. 2012-12726 (Patent Document 5), a method for improving the heat-shielding property of a knitted fabric by using a flat cross-section fiber is disclosed, and according to Japanese Patent Laid-Open No. 2014-177716 ( Patent Document 6) is known as a core-sheath type profiled composite fiber and a fiber assembly thereof. The core-sheath type profiled composite fiber is a leaf-shaped fiber with a core component containing 8 wt% (weight percent) or more 70% by weight or less, a thermoplastic polymer of a minute sunlight shielding substance, and a sheath component comprising a polyester polymer containing inorganic fine particles of 0.5% by weight or more and 10% by weight or less.

As described above, many kinds of knitted fabrics having heat-shielding properties and transparency prevention (hereinafter sometimes referred to as "permeability") have been known. However, knitted fabrics having more excellent heat-shielding properties and barrier properties are required.

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 4-257314

[Patent Document 2] Japanese Patent Laid-Open No. 9-157958

[Patent Document 3] Japanese Patent Laid-Open No. 11-81048

[Patent Document 4] Japanese Patent Laid-Open No. 9-137345

[Patent Document 5] Japanese Patent Laid-Open No. 2012-12726

[Patent Document 6] Japanese Patent Laid-Open No. 2014-177716

The present invention is based on the discovery that the following fibers exhibit new and significant characteristics The creator, wherein the fiber is a polygonal cross-section fiber in a specific range and has a hollow portion.

An object of the present invention is to provide a hollow polyester multifilament (multifilament) suitable for a four-corner cross section to an octagonal cross section of a knitted fabric that is lightweight and excellent in heat-shielding, light-shielding, and transparency properties, and the multi-angle cross-section hollow polyester multifilament. Processed yarn produced by false twisting of silk.

In addition, another object of the present invention is to provide a knitted fabric excellent in heat-shielding properties and barrier properties even when thinned, and various clothes using the knitted fabric.

The main configuration of the present invention satisfies any one of the following 1 to 16.

A fiber bundle in which the heat-shielding property of a knitted fabric at a basis weight of 140 g / m ² to 150 g / m ² in the form of a 16G rib knitted fabric is 40 ° C. or less, and the L ^* value is 1. above 50.

2. The fiber bundle according to the above 1, wherein the knitted fabric has a visible light transmittance of 30% or less, and the fiber bundle includes a polyester fiber.

3. The fiber bundle according to the above 1 or 2, wherein the single fiber of the fiber bundle has a cross-sectional shape of the fiber perpendicular to the fiber axis in a shape having 4 to 8 corners and having a single shape. The hollow portion of the hollow portion has a circular cross-sectional shape in a direction perpendicular to the fiber axis.

4. The fiber bundle according to any one of 1 to 3, which contains 1% to 3% by mass of titanium dioxide.

5. The fiber bundle according to any one of 1 to 4, wherein the The number of single fibers is 6 to 72.

6. The fiber bundle according to any one of 1 to 5, wherein a hollow ratio of the hollow portion is 10% to 40%.

7. The fiber bundle according to any one of 1 to 6, wherein the single fiber fineness is 1 dtex to 8 dtex, and the total fineness is 6 dtex to 575 dtex.

8. The fiber bundle according to any one of 1 to 7, wherein the single fiber strength is 2 cN / dtex to 5 cN / dtex.

9. A false twist processing yarn comprising the fiber bundle according to any one of 1 to 8 above, and a false twist coefficient of 8000 to 30,000.

A knitted fabric having a basis weight of 50 g / m ² to 180 g / m ² , a permeability of 95% or more, and an L ^* value of 50 or more.

11. The knitted fabric according to the above 10, wherein the cloth thickness is 0.2 mm to 0.5 mm.

12. The knitted fabric according to 10 or 11, wherein a transmittance of visible light having a wavelength of 400 nm to 780 nm is 24.5% or less.

13. The knitted fabric according to any one of the above 10 to 12, which has a heat-shielding property of 41.0 ° C or lower.

14. The knitted fabric according to any one of the above 10 to 13, which contains 30 to 100% by mass of the fiber bundle according to any one of the above 1 to 8.

15. A garment containing 70% or more of the knitted fabric according to any one of the above 10 to 14.

16. The clothing according to item 15, wherein the clothing includes uniforms and sportswear.

The hollow polyester multifilament of the quadrangular cross section to the octagonal cross section of the present invention is a fiber in which the cross-sectional shape of the fiber in a single yarn is a polygon in a specific range, and the surface of the fiber is made transparent by refraction of light Effect, and by containing more than 70% of the total number of single yarns, the cross-sectional shape of the fiber is a polygonal single yarn as described above, which can also be densely packed, thereby improving heat shielding properties, and having a hollow portion, not only The fiber becomes lightweight, and if the shape of the hollow portion of the fiber cross section is circular, the refraction of light becomes random, and the anti-transparency effect is further obtained. Even in the case of false twist processing, the hollow portion is difficult to break. When it is made into a knitted fabric, it can exhibit light weight, excellent heat-shielding property, light-shielding property, and transparency prevention.

Even if the knitted fabric of the present invention is made thin, the knitted fabric has superior heat-shielding properties and impermeability.

FIG. 1 is a photograph (400 times) of a cross section of an example of a fiber bundle of the present invention in a direction perpendicular to the fiber axis direction.

2 is a cross-sectional view of a fiber used in an optical simulation of a hexagonal cross-section hollow circle cross-section as an example of the present invention.

FIG. 3 is a diagram showing a result of an optical simulation of a hollow circle cross section of a hexagonal cross section as an example of the present invention.

4 is a cross-sectional view of a fiber used in an optical simulation of a hollow hexagonal cross-section of a hexagonal cross-section as an example of the present invention.

FIG. 5 is a diagram showing a result of an optical simulation of a hollow hexagonal cross section of a hexagonal cross section as an example of the present invention.

Hereinafter, embodiments of the present invention will be described in detail.

The fiber bundle of the present invention has a heat-shielding property of a knitted fabric at a weight per unit area of 140 g / m ² to 150 g / m ² in the form of a 16G rib knitted fabric of 40 ° C. or less, and a brightness L ^* value of 50 or more.

Using the fiber bundle of the present invention, a 16G knitting machine with 16 knitting needles per 1 inch was used to knit a rib structure, and the basis weight was 140 g / m ² to 150 g / m ² .

The type of the knitting machine is not particularly limited as long as it can be knitted into a rib knit. For example, a flat knitting machine and a circular knitting machine can be used.

Adjust the packing condition of the knitted hole to adjust the weight per unit area.

The heat-shielding property is measured by the measuring method mentioned later.

In addition, the lighter the color of the knitted fabric, the lower the heat-shielding effect. However, in the present invention, even if the brightness L ^* value of the knitted fabric is 50 or more than the neutral color, the effect of heat-shielding is also high.

Therefore, the fiber bundle of the present invention more easily obtains the heat shielding effect when the brightness L ^* is 60 or more, and the effect is more easily obtained when the brightness L ^* is 70 or more.

Brightness L ^{* is} represented by a numerical range from 0 to 100, where 0 is a dark color and 100 is a light white color.

Regarding the heat-shielding property of knitted fabrics, it is considered that the lighter the color becomes, the easier it is to transmit infrared rays. Line, so the heat shielding property becomes low.

In the fiber bundle of the present invention, the visible light transmittance of the knitted fabric is preferably 30% or less, and the fiber bundle includes a polyester fiber.

As for the visible light transmittance, the thinner the knitted fabric becomes, the higher the transmittance becomes, the lighter the color of the knitted fabric, and the higher the transmittance becomes. However, when the fiber bundle of the present invention is made into a knitted fabric, even if the knitted fabric is thin and the color of the knitted fabric is light, it is easy to reduce the visible light transmittance.

When the visible light transmittance is low, when it is made into clothes, it is less likely to see through underwear.

From this viewpoint, the visible light transmittance is more preferably 27% or less, and even more preferably 24% or less.

The type of the fiber of the fiber bundle of the present invention is not particularly limited as long as it is a chemical fiber. Examples include polyethylene terephthalate fibers, polyamide fibers, polyolefin fibers, and acrylic fibers. Among them, polyethylene terephthalate fibers are more preferred in terms of having a cool feeling and producing a profiled hollow fiber. Examples of the polymer constituting the polyester multifilament include polyesters having ethylene terephthalate as a main constituent unit, and the polyester may contain a copolymerization component. Examples of the copolymerization component include aromatic and aliphatic dicarboxylic acid components other than terephthalic acid components such as isophthalic acid components, isophthalic acid components containing metal sulfonic acid groups, and adipic acid components, and ethylene glycol. Aliphatic diol components other than the components.

The fiber bundle of the present invention is preferably a single fiber, and the cross-sectional shape of the fiber perpendicular to the fiber axis is a polygonal shape having 4 to 8 corners, and has a single shape. The hollow portion of the hollow portion has a circular cross-sectional shape in a direction perpendicular to the fiber axis.

The fiber cross section in the present invention means a fiber cross section in a direction perpendicular to the fiber axis. Since the cross-sectional shape of the single fiber has 4 to 8 corners, in the state of the fiber bundle, the single fibers are easily aligned with each other without gaps, thereby improving the densest filling property.

From the viewpoint, it is more preferable that the fiber cross-sectional shape of the fiber bundle of the present invention has six corners. When the cross-sectional shape of the fiber has six corners, the shape becomes a hexagon, and the densest filling can be performed, so the heat shielding property is improved. The corner of the hexagon may also have a circular arc, but the radius of curvature of the circular arc is less than the radius of the inscribed circle of the hexagon. In addition, even if all sides are not made of straight lines, as long as the hexagonal shape can be formed for the closest packing, the multifilament may include a part of the fiber cross-sectional shape with a curved side or a corner with a rounded corner. Angled single yarn.

In addition, the hexagons in the present invention also include those that cannot be called geometric hexagons. Among the hexagons, especially those that are equal to or similar to the following hexagons, that is, each side of an arbitrary side adjacent to the side The internal angle of the corners where the straight portions intersect with each other is 120 degrees, and the hexagons have the same length between the adjacent corners and the corners. At this time, there may be an error in the angle of the inner corner or the length of the adjacent side.

In addition, the single fiber constituting the fiber bundle of the present invention has a single hollow portion in its fiber cross section, and by setting the single hollow portion to a single hollow portion, the hollow ratio can be increased. In the present invention, the hollow ratio of the hollow portion of the single fiber is preferably 10% to 40%. By having a hollow portion to form a layer of air, the refractive index becomes higher, and further, the fiber cross-sectional shape of the hollow portion of the single fiber is preferably a circular shape in which the refraction of light becomes random.

As shown in Fig. 2 and Fig. 4, when the intensity of light in the normal direction is used to compare the fiber cross-sectional shape of a single fiber with a hexagonal cross-section and a hollow section with a hexagonal cross-section in an optical simulation, it is It can be seen that the intensity of the hollow section with a circular cross section is 20, as shown in FIG. 5, and the intensity of the hollow section with a hexagonal cross section is 110. As shown in FIG. Through.

The optical simulation was performed by the following method.

The analysis software was performed using LightTools version 8.2 (Synopsys, Inc.).

As conditions, the following conditions are set.

． Hollow fibers are modeled in three dimensions.

． It is assumed that the refractive index of the material is a polyester fiber of 1.6.

． Fresnel loss is set on the fiber surface.

． It is assumed that light emitted from the light source in a range of only 0 ° to 5 ° in the normal direction.

． A light-receiving part was set on the side opposite to the light source, and the angular distribution of the light which irradiated the fiber at least once and reached the light-receiving part was obtained.

． Considering that the direction of the fibers becomes random, a total of 12 groups in which the fibers are rotated by 60 ° in units of 5 ° is determined.

The fiber bundle of the present invention includes, in a cross section of a multifilament composed of a single yarn having a hexagonal cross section of a fiber, a single fiber having a regular hexagonal cross section of 50% or more of the total number of single fibers. There are many single fibers with a regular hexagonal cross-sectional shape, and it is possible to further improve the densest filling property. From the viewpoint, it is preferable that the cross-sectional shape of the fiber including 70% or more of the total single fiber number is regular six. Angled single fibers are more preferably 80% or more.

The cross section of the single fiber refers to the cross section of the single fiber in a direction perpendicular to the fiber axis direction.

The fiber bundle of the present invention preferably contains 1% to 3% by mass of titanium dioxide.

When the titanium dioxide is contained in an amount of 1% by mass or more, the anti-transparent effect tends to be good, and when it is 3% by mass or less, the yarn-making property is easily improved.

From this viewpoint, the content of titanium dioxide is more preferably 1.5% by mass to 2.5% by mass.

The fiber bundle of the present invention is preferably a fiber bundle having a single fiber number of 6 to 72. If the number of the single fibers is 6 or more, it is easy to perform the densest filling and obtain the anti-transparent effect. If the number of the single fibers is 72 or less, the thickness of the fiber bundle as a whole will not be too thick for clothing applications. good. From this viewpoint, the number of single fibers of the fiber bundle is more preferably 12 to 48, and even more preferably 16 to 40.

When the hollow ratio is 10% or more, the refraction of light is large and the anti-transparent effect is increased. Moreover, if the said hollow ratio is 40% or less, when a false twist process is performed, it will become difficult to damage a hollow part. From the viewpoint, the hollow ratio is more preferably 15% to 30%, and even more preferably 20% to 27%.

The fiber bundle of the present invention preferably has a single fiber fineness of 1.0 dtex to 8.0 dtex. If the single-fiber fineness is 1.0 dtex or more, the yarn-making stability becomes good, and yarn breakage is reduced during the production of knitted fabrics, and the productivity tends to be good. Therefore, it is preferably used. The feel in the middle does not become too hard, because it can increase the single The number of fibers can cause a lot of light refraction, and the effects of anti-permeability and heat-shielding are easy to appear, and it is easy to manufacture a thin knitted fabric, and at the same time, it is easy to obtain a soft feel, so it is preferable. From the viewpoint, the single fiber fineness is more preferably 2.0 dtex to 6.0 dtex.

The fiber bundle of the present invention preferably has a total fineness of 6 dtex to 575 dtex. If the total fineness is 6 dtex or more, the densest filling can be performed and the heat shielding effect is improved. Therefore, it is preferable. If the total fineness is 575 dtex or less, the hand feeling in clothing applications is not too hard, so it is preferable. From the viewpoint, the total fineness is more preferably 32 dtex to 240 dtex, and even more preferably 50 dtex to 120 dtex.

The fiber bundle of the present invention preferably has a single fiber strength of 2.0 cN / dtex to 5.0 cN / dtex. If the single fiber strength is 2.0 cN / dtex or more, it is preferable that the fiber bundle is difficult to break when weaving or weaving into a knitted fabric. The upper limit of the fiber strength is sufficient if it is about 50 cN / dtex.

[Regarding the form of the fiber bundle] The fiber bundle of the present invention is preferably a long fiber in terms of its characteristics, but it can also be made into a short fiber to form a web or a textile yarn containing the short fiber.

The fiber bundle of the present invention is produced by melt spinning, for example, using polyethylene terephthalate having an intrinsic viscosity of 0.676 as a raw material, and preferably adding a matting agent such as titanium dioxide. In the case of titanium dioxide, since the matting effect is improved and the anti-transparent effect is also obtained, it is preferable to add 1.0 to 3.0% by mass of titanium dioxide.

As the spinning head at the time of melt spinning, a group of nozzle holes formed by arranging six central folding slits with an inner angle of 120 degrees in a ring shape can be preferably used, and a plurality of the nozzle holes can be used. Spinning head. According to the spinning head having the nozzle hole, The internal angle of each vertex is 120 degrees, and the cross-sectional shape of a regular hexagon is the same as a regular hexagon with the length of each side between the vertex and the vertex.

The melt-spinning can be produced by a general melt-spinning step and an elongation step in the same manner as the melt-spinning of ordinary round cross-section solid fibers of polyethylene terephthalate. First, in the melt spinning step, a thermoplastic resin as a raw material is melt-extruded from a spinning head to obtain an unstretched yarn. After being temporarily wound up, it is stretched in the stretching step to obtain fibers. The stretching step can be continuously stretched in-line after spinning the unstretched yarn, or it can be independently stretched on another production line after being temporarily wound up. In addition, the extending step may be one step, or may be a plurality of steps of two or more steps. Furthermore, the heat source used in the extension step may be any of a contact-type or a non-contact-type heat source. The draw ratio may be arbitrarily set within a range before the elongation at break of the undrawn yarn that has been melt-spun.

For example, spray from the spinning head at a spinning temperature of 270 ° C to 300 ° C and extract at a spinning (extraction) speed of 1000m / min to 2000m / min to make an unstretched yarn, and then stretch at a speed of 200m / Min ~ 800m / min, stretching ratio is 0.65 to 0.80 times of maximum stretching ratio, stretching temperature is 60 ° C to 90 ° C, heat setting temperature is 100 ° C to 170 ° C, and the original yarn is obtained as the drawing yarn. Invented hexagonal cross section hollow polyester multifilament. The so-called maximum draw ratio refers to the draw ratio when the undrawn yarn is broken at an elongation temperature of 80 ° C, a heat setting temperature of 145 ° C, and an elongation speed of 600 m / min.

In addition, during the yarn manufacturing process, the undrawn yarn of the warp spun yarn can be temporarily wound and then stretched, and the undrawn yarn of the warp spun yarn can be drawn without being taken up. High-speed spinning at a speed of 2000 m / min or more and winding as a semi-unstretched yarn, or stretching after high-speed spinning without winding.

The false-twist processing yarn of the present invention is a false-twist processing yarn having a false-twist coefficient of 8000 to 30,000, which is obtained by false-twisting the fiber bundle of the present invention. In the case where the fiber bundle of the present invention has 4 to 8 corners in the cross-sectional shape of a single fiber, and has a round hollow portion, the hollow portion is hardly damaged even when subjected to external forces such as false twist. If the false twist coefficient is 8,000 or more, it is preferable to obtain a feeling of swelling as a crimped yarn, and if it is 30,000 or less, the hollow portion is difficult to break, so it is preferable. From the viewpoint, the false twist coefficient is more preferably 10,000 to 25,000.

Hereinafter, the form of the knitted fabric of this invention is demonstrated in detail.

The knitted fabric of the present invention has a basis weight of 50 g / m ² to 180 g / m ² , a permeability of 95% or more, and a brightness L ^* value of 50 or more.

When the weight per unit area is 50 g / m ² or more, the effect of barrier properties is easily obtained. In addition, if the basis weight is 180 g / m ² or less, a soft feel is easily obtained.

From the viewpoint, the basis weight is more preferably 70 g / m ² to 160 g / m ² or less, and even more preferably 90 g / m ² to 130 g / m ² or less.

The permeability of the knitted fabric of the present invention is 95% or more. If the permeability is 95% or more, it is a level that does not need to worry about seepage through underwear or the like. From the viewpoint of permeability, the permeability is more preferably 95.2% or more.

The knitted fabric of the present invention has a brightness L ^* value of 50 or more.

The brightness L ^* value is an index indicating the density of a color, and is represented by a range from 0 to 100. 0 is black and dark, and 100 is white and light.

The barrier properties vary depending on the color. The lighter the color of the knitted fabric, the lower the effect. However, in the present invention, even if the knitted fabric has a brightness L ^* value of 50 or more, it is lighter than the medium color. The effect of anti-permeability is also high.

Therefore, when the brightness L ^* of the fiber bundle of the present invention is 60 or more, the effect of permeability prevention is more easily obtained, and when the brightness L ^* is 70 or more, the effect is more easily obtained.

The cloth thickness of the knitted fabric of the present invention is 0.2 mm or more and 0.5 mm or less. When the thickness of the cloth is 0.2 mm or more, it is difficult to be broken during the manufacture or use of the clothing, and the heat-shielding property and the permeability are easily improved. When the thickness is 0.5 mm or less, a desired thin knitted fabric can be obtained. .

From the viewpoint, the lower limit value of the cloth thickness is preferably 025 mm or more, more preferably 0.27 mm or more, and the upper limit value of the cloth thickness is preferably 0.45 mm or less, and more preferably 0.40 mm.

The knitted fabric of the present invention preferably has a transmittance of visible light having a wavelength of 400 nm to 780 nm of 24.5% or less.

If the said transmittance is 24.5% or less, it is a level which does not need to worry about see-through of underwear, etc.

From the viewpoint, the transmittance is more preferably 24.0% or less, and still more preferably 23.5% or less.

The knitted fabric of the present invention preferably has a heat shielding property of 41.0 ° C or lower. If the heat-shielding property is 41.0 ° C. or less, even if sunlight is irradiated, radiant heat can be suppressed, and the temperature rise in clothing can be slowed down, so that a comfortable time can be extended. In view of In other words, the heat shielding property is more preferably 40.8 ° C or lower.

The knitted fabric of the present invention preferably contains the fiber bundle in an amount of 30% by mass or more and 100% by mass or less.

When the content of the multifilament with respect to the knitted fabric is 30% by mass or more, the barrier properties and heat shielding properties tend to be good, more preferably 50% by mass or more, and even more preferably 80% by mass or more and 100% by mass. %the following.

The cross-sectional shape of the single fiber used in the direction perpendicular to the fiber axis is a shape with 4 to 8 corners, and has a single hollow portion, so that the light passing through the braid is easily diffused and prevented from transmitting. Properties and heat shielding properties tend to be good.

The shape of the cross section of the single fiber is preferably a hexagon, and is more preferably a regular hexagon, but it may not be a regular hexagon.

In the knitted fabric of the present invention, the cross-sectional shape of the hollow portion in a direction perpendicular to the fiber axis is preferably a circular cross-section.

Since the cross-sectional shape in the direction perpendicular to the fiber axis in the hollow portion is a circular cross-section, light is easily diffusely reflected, and transparency and heat shielding properties tend to be better.

Here, the circular cross section is preferably a perfect circle, but may be an ellipse, and preferably has a curved portion of 50% or more.

The structure of the knitted fabric of the present invention is not particularly limited. It is preferably thin and filled with woven holes, so the structure of the fabric is more preferably flat woven. In the knitted fabric, a plain weave or a smooth weave is preferred.

The clothes of the present invention are those containing 70% by mass or more of the knitted fabric. When the knitted fabric is contained in an amount of 70% by mass or more, it is easy to obtain a knitted fabric having good permeability and heat shielding properties. clothes.

From the viewpoint, it is preferable that the knitted fabric contains 85% by mass or more, more preferably the knitted fabric contains 95% by mass or more, and most preferably 100% by mass.

The clothes of the present invention preferably include uniforms and sportswear.

In the case of uniforms, permeability is more required. In particular, uniforms used in hospitals are mostly light-colored, and the thickness of the cloth is thin. Therefore, the fiber bundle and knitted fabric of the present invention can be suitably used.

In addition, the thickness of the cloth for sportswear is thin, and it is easy to be transparent when the cloth is wet due to sweat, and it is also used outdoors. Therefore, it is more required to have permeability resistance and heat shielding. Fabric.

[Example]

Hereinafter, the present invention will be described more specifically based on examples.

In addition, each characteristic value in an Example was measured by the following method.

[Judgment of regular hexagon]

Using a light microscope (400 times), a cross-section of a single fiber of a fiber bundle (in this specification, sometimes referred to as a "multifilament") was photographed, and a hexagonal corner (apex) of the fiber section was measured. The angle of the internal angle and the length between adjacent vertices are determined.

[Hollow ratio (%)]

The cross section of the single fiber of the fiber bundle of the sample was photographed using an optical microscope (400 times), and the ratio of the hollow portion area to the cross-sectional area of the fiber including the hollow portion was calculated and set as the hollow ratio (%).

[Content ratio (%) of single fiber having a regular fiber cross-sectional shape]

Use a light microscope (400 times) to take a photograph of the cross section of the fiber bundle of the sample perpendicular to the length direction, measure the total number of single fibers and the number of single fibers in the regular hexagonal section, and calculate the number of single fibers in the regular hexagonal section. The proportion of the total number of single fibers is taken as the content (%) of the single fibers in the regular hexagonal section. The measurement was performed at the cross-section site of arbitrary three sites, and the average value was calculated.

[Yarn unevenness (U%)]

The measurement was performed at a measurement speed of 15 m / min using a yarn unevenness tester (Evenness Tester KET-80C manufactured by Kyo Kogyo Co., Ltd.). The number of measurements was three times and the average value was calculated.

[Water absorption]

According to the following (general corporation) textile inspection (BOKEN) quality evaluation agency water absorption test method.

Dropping method: One drop of water was dropped from a height of 10 cm on a test piece mounted on a holding frame, and the time (seconds) until the water droplet disappeared from the test piece was measured.

Byreck method: The upper end of a test piece having a length of 200 mm × 25 mm was fixed, and the lower end was drooped to be immersed in water. After being left for 10 minutes, the height (mm) of water rising on the test piece was measured.

[Heat retention (%)]

According to the following (general consortium) textile insulation quality evaluation agency thermal insulation test method.

Using KES-F Thermo Lab II manufactured by Kato Tech The testing machine sets the test piece on a hot plate set at a fixed temperature (ambient temperature + 10 ° C), and determines the amount of heat (a) that is dissipated through the test piece. It also calculates the amount of heat emitted without the test piece installed. The amount of heat (b) is calculated from the following formula.

Insulation rate (%) = (1-a / b) × 100

[Transmittance(%)]

Using an ultraviolet-visible spectrophotometer (manufactured by JASCO Corporation, V-670), the transmittance (%) of light was measured in each wavelength region listed below. The transmittance is determined by the following formula based on the sum of the transmittances per 5nm wavelength of the test piece (cumulative amount Ts) and the sum of the background transmittances of each 5nm wavelength without the test piece (cumulative amount Tg).

Transmittance (%) = (Ts / Tg) × 100

Ultraviolet light; measurement wavelength range 250nm ~ 400nm

Visible light; measurement wavelength range 400nm ~ 700nm

Infrared light; measurement wavelength range 700nm ~ 2000nm

[Heat shielding property (℃)]

According to the following (general corporation) Kaken Test Center's reflector lamp method.

A 30cm × 30cm knitted fabric sample was managed at an ambient temperature of 20 ° C and wet. The test chamber was left at rest for 65 hours with a degree of 65%. The knitted fabric sample was held above 5 mm of the infrared light receiving body (black drawing paper), and the sample was irradiated with the light of a reflector lamp from a distance of 50 cm from the sample side, and the sample was chronologically aligned with the sample by a thermocouple. The temperature of the center of the infrared light receiving body on the opposite side was measured for 15 minutes, and the temperature after 15 minutes was set to the heat-shielding temperature.

The test was performed 6 times under the following conditions.

Operating lamp: EYE LAMP <SPOT> PRS100V500W manufactured by Iwasaki Electric Co., Ltd., laboratory temperature: 20 ℃ ± 2 ℃,

Laboratory humidity: 65%,

Each value obtained by averaging the data is set as a test result.

[Impermeableness (%)]

A 30 cm × 30 cm knitted fabric sample was allowed to stand in a test room managed at an ambient temperature of 20 ° C. and a humidity of 65% for 24 hours. The fabric samples were stacked on white tiles and the brightness was measured using a spectrophotometer. Furthermore, the sample was stacked on a black tile, and the brightness was measured using a spectrophotometer.

Impermeability (%) = (Brightness when using black tiles (L ^* ) / Brightness when using white tiles (L ^* )) × 100

Test machine: HunterLab spectrophotometer UltraScanPRO,

Measurement conditions: The field of view is 10 degrees, the light source is D65, and the specular reflection light is removed.

[Visible light transmittance (%)]

A 30 cm × 30 cm knitted fabric sample was allowed to stand in a test room managed at an ambient temperature of 20 ° C. and a humidity of 65% for 24 hours. Using a spectrophotometer (U-3400 manufactured by Hitachi, Ltd.), the following (1) to (5) were sequentially performed on the fabric sample, and the measurement was performed.

(1) Prepare a knitted fabric for measurement.

(2) The transmittance (%) (hereinafter referred to as Tg) in the state without a sample is measured every 5 nm in the range of the wavelength of light from 250 nm to 2000 nm.

(3) The sample is mounted on a spectrophotometer, and transmittance (%) (hereinafter, referred to as Ts) in a state where the sample is in a range of 250 nm to 2000 nm in light wavelength is measured every 5 nm.

(4) Within the range of 250 nm to 2000 nm, use the following formula to correct Ts every 5 nm, and calculate the corrected transmittance (hereinafter referred to as T).

T = (Ts / Tg) × 100

(5) Calculate the arithmetic mean of T in the visible light region from 400 nm to 780 nm, and set it as the visible light transmittance.

[Brightness (L ^* value)]

Use a color meter (CM-7000d manufactured by Konica Minolta), set the index to 8 ° gloss, set the field of view to 2 °, and set the mode to SCE (remove regular reflection Light), the light source was set to D65 light, the second light source was set to C light, and the L ^* value of a 10 cm × 10 cm fabric sample was measured under a fabric sample through a black paper.

The measurement was performed five times at each of the three positions of the fabric sample, and the average value was set to the L ^* value.

(Example 1)

Polyethylene terephthalate with an intrinsic viscosity of 0.676 added with 2% by mass of titanium dioxide was used. Six centrally folded 120 slits with an internal angle of 120 degrees were arranged in a ring shape with a diameter of φ1.0 mm. The nozzle holes are one group, and a spinning head having 36 groups of the nozzle holes is used to spin at a spinning temperature of 280 ° C., and is wound up at an extraction speed of 1400 m / min to form an unstretched yarn, which is further extended into 0.69 times the maximum draw ratio to produce a full-matt 84dtex / 36filament (f) (a single yarn fineness of 2.3dtex) polyester multifilament. As shown in FIG. 1, the obtained polyester multifilament is a circular single fiber having a fiber cross-sectional shape of a regular fiber in a cross section of the multifilament and a single hollow portion in the cross section of the fiber having a hollow ratio of 17.5%. Multi-filament with 89% fiber count.

The fiber physical properties of the obtained polyester multifilament had a strength of 3.70 cN / dtex, an elongation of 41.3%, a BWS of 8.1%, and a U% of 0.48.

In addition, the obtained polyester multifilament was subjected to false twist processing with a false twist coefficient of 14,000. As a result of observing the fiber cross section of the single yarn of the false-twisted processed yarn, no breakage was observed in the hollow portion.

Using the obtained polyester multifilament, a rib knitted fabric was knitted with a 16G flat knitting machine. The evaluation results of the obtained knitted fabric are shown in Table 1. The obtained knitted fabric was the color of the undyed raw yarn.

It can be seen that the transmittance of visible light is lower than that of the comparative example, and therefore the permeability is high. although It is light-colored, but has high heat-shielding property and barrier property compared with the comparative example.

(Example 2)

In Example 1, a group of nozzle holes with a diameter of φ1.0 mm formed by arranging six central folding slits with an inner angle of 120 degrees in a ring shape was replaced with a group of 18 spinning holes having the nozzle holes. Except for the yarn end, a multifilament of 84 dtex / 18f (single yarn fineness of 4.7 dtex) was produced in the same manner as in Example 1. The obtained polyester multifilament was a circular single fiber having a fiber cross-sectional shape of a regular hexagon in the fiber cross section of the multifilament and a single hollow portion in the fiber cross section of 25.3%, accounting for 94% of the total number of single fibers. Multifilament. The fiber physical properties of the obtained polyester multifilament had a strength of 4.00 cN / dtex, an elongation of 32.9%, a BWS of 7.4%, and a U% of 0.42.

In addition, the obtained polyester multifilament was subjected to false twist processing with a false twist coefficient of 14,000. As a result of observing the fiber cross section of the single yarn of the false-twisted processed yarn, no breakage was observed in the hollow portion.

Using the obtained polyester multifilament, a rib knitted fabric was knitted with a 16G flat knitting machine. The evaluation results of the obtained knitted fabric are shown in Table 1. The obtained knitted fabric was the color of the undyed raw yarn.

It can be seen that the transmittance of visible light is lower than that of the comparative example, and therefore the permeability is high. Although it is light-colored, it has high heat-shielding property and barrier property compared with the comparative example.

(Comparative example)

As in the knitted fabric in Example 1, a polyester multifilament using a semi-matte 84 dtex / 36f (single yarn fineness 2.3 dtex) was knitted into the obtained knitted fabric in the same manner as in Example 1, and the obtained control knitted fabric was evaluated. The evaluation results of the products are shown in Table 1. The polyester multifilament is the same polyethylene terephthalate as used in Example 1, and uses a spinning head having 36 circular nozzle holes with a diameter of 0.25 mm in diameter. The cross-sectional shape of the produced single fiber was a circular cross-section solid fiber having a circular cross-section and no hollow portion. The strength of the fiber properties of the polyester multifilament used was 4.25 cN / dtex, the elongation was 36.1%, the BWS was 8.1%, and the U% was 0.43.

(Example 3)

The polyester multifilament obtained in Example 1 was used for warp and weft to produce a plain weave fabric. Thereafter, a dyeing process is performed using a fluorescent disperse dye.

Table 2 shows the evaluation results of the basis weight, cloth thickness, heat shielding property, permeability resistance, visible light transmittance, and brightness of the obtained fabric.

Since this fabric is dyed using a fluorescent disperse dye, it has a very light brightness that is close to that of uncolored raw yarn, but has excellent heat-shielding properties, barrier properties, and low visible light transmittance.

(Comparative example 1)

A woven fabric was obtained in the same manner as in Example 1 except that the used yarn was a mixed yarn having a profiled cross section and a circular cross section (manufactured by Toray Co., Ltd., "CEO α" (model H67L) FD84T48F).

The evaluation results are shown in Table 2.

(Comparative example 2)

Except that the used filament was a single-fiber cross-sectional shape having a flat cross-section having two or more intermediate thinned portions (manufactured by Teijin Fibers, Ltd., "Waveron" (model F0212) FD84T30F), the same examples were used 1 Fabric was obtained in the same manner.

The evaluation results are shown in Table 2.

(Comparative example 3)

A woven fabric was obtained in the same manner as in Example 1 except that the cross-sectional shape of the filament used was a single cross-section and that contained 0% titanium oxide (manufactured by Nanya (Company), full matte yarn FD84T30F). .

The evaluation results are shown in Table 2.

[Industrial availability]

The fiber bundle, the processed yarn, and the knitted fabric using the fiber bundle are light-weight and excellent raw materials with excellent heat-shielding, permeability, and transparency. Therefore, the fiber bundle is suitable for knitting of white clothing such as sports clothing, work clothing, and nurse white clothing. Raw materials for fabrics.

Claims (13)

A knitted fabric containing a fiber bundle having a single fiber fineness of 1 dtex to 8 dtex in a range of 30% by mass to 100% by mass. The single fiber of the fiber bundle has a single hollow portion and contains 1% to 3% by mass of titanium dioxide. Area weight is 50g / m ² to 180g / m ² , permeability is 95% or more, and L * value is 50 or more. The knitted fabric according to item 1 of the scope of patent application, wherein in the single fiber of the fiber bundle, the fiber cross-sectional shape in a direction perpendicular to the fiber axis is a shape having 4 to 8 corners, and the hollow portion The cross-sectional shape of the direction perpendicular to the fiber axis is circular. A knitted fabric comprising a fiber bundle having a single fiber fineness of 1 dtex to 8 dtex in a range of 30% to 100% by mass, and a cross-sectional shape of a fiber of a single fiber of the foregoing fiber bundle perpendicular to a fiber axis has 4 to 8 And has a weight per unit area of 50 g / m ² to 180 g / m ² , an impermeability of 95% or more, and an L * value of 50 or more. The knitted fabric according to item 3 of the scope of patent application, wherein the single fiber of the fiber bundle has a single hollow portion, and the cross-sectional shape of the hollow portion in a direction perpendicular to the fiber axis is circular. The knitted fabric according to item 3 of the scope of patent application, which contains 1% to 3% by mass of titanium dioxide. The knitted fabric according to item 1 or item 3 of the scope of patent application, wherein the number of single fibers of the fiber bundle is 6 to 72. The knitted fabric according to item 1 or item 4 of the scope of patent application, wherein the hollow portion has a hollow ratio of 10% to 40%. The knitted fabric according to item 1 or item 3 of the scope of patent application, wherein the total fineness is 6dtex to 575dtex. The woven fabric according to item 1 or item 3 of the scope of patent application has a cloth thickness of 0.2 mm to 0.5 mm. According to the knitted fabric described in item 1 or 3 of the scope of patent application, the visible light transmittance of the wavelength of 400nm ~ 780nm is less than 24.5%. The knitted fabric according to item 1 or item 3 of the scope of patent application has a heat-shielding property of 41.0 ° C or lower. A garment containing more than 70% of the knitted fabric according to any one of the scope of claims 1 to 11 of the scope of patent application. The clothing according to item 12 of the scope of patent application, wherein the clothing is a uniform or a sportswear.