Patent Application
20130196561
1. Field of the Invention
The present invention relates to a high-density woven fabric for garment applications or for sundry applications in the living space, particularly relates to a low air-permeable high-density woven fabric using high twisted multifilament yarns.
2. Prior Art
Conventionally, for the purpose of obtaining a dense structure, most of high-density multifilament woven fabrics have usually used nontwisted yarns or weak twisted yarns that are twisted to such a degree that weaving properties are not impaired. In a woven fabric that uses nontwisted multifilament yarns having no twists or low-twist multifilament yarns 1 with a small number of twists, filament yarns forming the yarn are bundled in parallel with each other or in a similar state, whereby a large number of long capillaries 1a are formed in the woven fabric (see
A high-density woven fabric of prior art using multifilament yarns as mentioned above, particularly a water-repellent fabric, has disadvantages in that although water hardly penetrates, when it is used, such as when it is worn, pressure or the like is applied, and thus once water penetrates, then water is held in the capillaries, making it difficult to dry. Its low air-permeability due to high density has also been another cause of slow drying. Improvement on such disadvantages to shorten or eliminate the drying time after washing also leads to energy saving, and thus has been greatly demanded in this technical field.
Meanwhile, as a high-density woven fabric using a high twisted multifilament yarns, for example, disclosures in JP-A-11-302944 related to “method for producing high-density woven fabric” and JP-A-2001-140115 related to “waterproof raincoat” are known.
JP-A-11-302944 discloses a high-density woven fabric for imparting high water-pressure resistance with excellent washing durability, in which yarns that are ultra fine multifilament yarns of 0.5 denier or less having a twist coefficient of 2000 to 5000 is used as the warp. However, this high-density woven fabric is to prevent, during dense weaving with a fluid injection weaving machine using the warp without a glue, a significant decrease in weaving properties due to fluff resulting from single-yarn breakage in ultra fine filaments. It does not provide a solution to the disadvantages of a high-density woven fabric of prior art, which is the elimination of water retention in capillaries to shorten the drying time after washing.
In addition, JP-A-2001-140115 discloses a high air-permeable raincoat, in which a cloth having a water resistance of 300 mm or more is used in a portion where, when worn, vertically falling raindrops hit at an angle of 45° or more, while a water-repellent cloth made of high twisted yarn woven fabric having an air-permeability of 50 cc/cm2/sec or more is used in the remaining portion. However, this high-density woven fabric does not provide a solution to the disadvantages of a high-density woven fabric of prior art either, which is the elimination of water retention in capillaries to shorten the drying time after washing.
An object of the invention is to solve the disadvantages of a high-density woven fabric of prior art mentioned above and provide a water-repellent, low air-permeable high-density woven fabric using high twisted multifilament yarns. The woven fabric has excellent drying properties owing to efforts to reduce the size of capillaries or minimize the formation of capillaries and also has excellent rub-resistant water repellency imparted by water-repellent treatment.
The present inventor has conducted extensive research on how multifilament should be in order to discourage the formation of a capillary structure, which is a cause of the disadvantages of the high-density woven fabric of prior art, particularly a water-repellent, high-density woven fabric. As a result, he has found that by twisting multifilament, long capillaries are destroyed or reduced in size, or the formation thereof is discouraged, and thus accomplished the invention. That is, by using high twisted multifilament yarns, a large number of long capillaries formed with multifilament are changed into short capillaries, whereby the gap is reduced, forming a low air-permeable high-density woven fabric that suppresses the penetration of water.
Here, a low air-permeable high-density woven fabric according to an aspect of the invention is obtained by applying water-repellent treatment to a woven fabric containing high twisted yarns with a twist coefficient of 5100 or more in a proportion of 50% or more of the surface area of the woven fabric. The low air-permeable high-density woven fabric has air-permeability of 50 cc/cm2/sec or less, a cover factor of 1500 or more, and a rub-resistant water repellency of 100 or more.
It is preferable that the low air-permeable high-density woven fabric is a woven fabric containing hydrophobic high twisted multifilament yarns with a twist coefficient of 7000 to 25000 in a proportion of 50% or more of the surface area of the woven fabric and having a cover factor of 2000 or more. The high twisted yam has a thickness of 30 to 150 denier, and individual single yarns forming the high twisted yarn have a thickness of 0.3 to 2.2 denier.
It is more preferable that the low air-permeable high-density woven fabric is in the form of a low air-permeable high-density plain-woven fabric, mat-woven fabric, or twill-woven fabric using hydrophobic high twisted multifilament yarns with a twist coefficient of 7000 to 25000 as the warp and weft. It is also preferable that the low air-permeable high-density woven fabric has a water resistance of 200 mm or more.
According to the low air-permeable high-density woven fabric, it uses high twisted yams, and therefore, continuous capillaries are less likely to be formed, the capillary diameter is also small, and moisture retention is low. Accordingly, the fabric is high-density woven one but has low water absorption. In addition, even after the woven fabric absorbs water, it dries quickly. The woven fabric is thus valuable as an energy-saving material for general garments, particularly for uniform garments. In addition, the woven fabric is resistant to wrinkling and thus provides excellent wearing comfort and convenience in handling when used as a garment.
Further, although high twisted yarns are used, because the fabric is woven in high density, the woven fabric does not have a crinkled appearance like a high twisted yarn woven fabric of prior art. The surface of the woven fabric only has fine irregularities according to the small yam diameter of the constituent filaments, and thus the outer appearance just looks smooth.
In addition, with respect to the water repellency of the low a -permeable high-density woven fabric, particular, it has extremely excellent rub-resistant water repellency.
The proportion of the high twisted yarns used in the low air-permeable high-density woven fabric according to the invention is preferably 50% or more, more preferably 65% or more, in terms of the percentage of the area to the surface area of the woven fabric calculated using the woven fabric structure (structure diagram), yarn density, and yarn thickness (corresponding to yarn diameter). The proportion is most preferably 100%.
By twisting, multifilament is twisted together. As a result, unlike the capillary la having a parallel or nearly parallel arrangement made of nontwisted multifilament or weak twisted multifilament 1 shown in
The method for twisting a yarn is not particularly limited, and it is possible to use a twisting machine such as a double twister. It is also possible to use a fancy-twisting machine for adjusting the surface irregularities 3b using several multifilament yarns, for example. Also in the case where several multifilament yarns are twisted, it is preferable to work first twist with respect to each multifilament yarn beforehand in a predetermined manner.
In order to obtain water repellency that is resistant to hard rubbing, as compared with a yarn obtained by fancy-twisting, a yarn obtained by twisting one multifilament yarn using a twisting machine such as a double twister provides a woven fabric with finer surface irregularities that are structurally more stable to the pressure of rubbing or the like, and thus is more preferable. Also in order to obtain a low air-permeable high-density woven fabric having waterproofness imparted by water-repellent treatment, twisting one multifilament yarn using a twisting machine such as a double twister provides a dense low air-permeable high-density woven fabric and thus is preferable.
These properties are advantageous also when the woven fabric is worn as a garment. That is, when it is worn in the rain, water is hardly retained therein. Therefore, unlike a fabric of prior art, it is unlikely to happen that the fabric holds water, and the surface gets wet with water and invites more water.
The low air-permeable high-density plain-woven fabric, mat-woven fabric, and twill-woven fabric according to the invention have a structure in which the gap between yarns is small, and thus capillaries are unlikely to be formed between yarns. Further, because of the increased density, crinkling due to a high twisted yarn is also unlikely to occur, and thus the structure has fewer floats. In order to decrease air-permeability and increase windproofness, and also in order to perform water-repellent treatment to impart waterproofness, the plain-woven fabric, mat-woven fabric, and twill-woven fabric according to the invention having fewer floats are suitable.
Further, in terms of density, in order not to cause crinkling as in a woven fabric of prior art using a high twisted yarn, it is at least necessary that the woven fabric has a dense structure such that the total cover factor, which is the sum of the cover factors of the warp and weft defined by the equations mentioned below, is 1500 or more, more preferably 2000 or more. By further increasing the density and further performing water-repellent treatment, water repellency and waterproofness resistant to rubbing are obtained in addition to windproofness. When the woven fabric is densified to a total cover factor value of about 2500 or more, a waterproofness of 250 mm or more, which is required in garment fabrics, umbrella fabrics, and tent fabrics, is obtained.
In the past, high twisted yarns have been used to create an aesthetic outer appearance by forming crinkled woven fabrics. adjusting the texture, or so. A high twisted yarn has strong untwisting force (shrinkage). Making good use of this force, high twisted yarns have been used to form large irregularities or crinkles on the surface of a woven fabric by weaving them into a fabric, followed by untwisting to cause shrinkage. Yarn-twisting itself has also been used to create the aesthetic outer appearance of a woven fabric by providing the yarns with varying thickness. That is, in order to produce crinkles or large irregularities on the surface of a woven fabric, the woven fabric design has also been devised. For example, a woven fabric has been designed to decrease the density between yarns so that a high twisted yarn easily shrinks to form crinkles or irregularities, or the woven fabric structure has been devised to cause crinkling for adjusting the outer appearance or adjusting the texture of the woven fabric, In addition, a high twisted yarn has also been used only as the weft to provide a woven fabric with a willow-patterned, crinkled appearance. These woven fabrics of prior art focusing on crinkling using a high twisted yarn have a gap formed between yarns and thus are high air-permeable,
In the present invention, the fabric is densely woven so that the untwisting force of the high twisted yarn mentioned above is not generated. Further, the high twisted yarn is not used to cause crinkling as in prior art, but has been devised to produce no capillary structure or produce capillaries with a reduced diameter and reduced length. That is the high twisted yarn woven fabric of the invention is densely woven to form no gap between yarns so that the woven fabric does not shrink to cause crinkling during the scouring, relaxing and dyeing processes after weaving. As a result, the suppression of gap formation and the suppression of crinkling have been successfully achieved, and short capillaries having a small diameter, which are characteristic to high twisted yarns, have been introduced into a high-density woven fabric. Thus, a high-density woven fabric that solves the disadvantages of a high-density woven fabric of prior art, has low water absorption even when wetted with water, and dries quickly has been successfully developed for the first time, In order to increase the density of a woven fabric to such a degree that crinkling does not occur, it is necessary that the woven fabric has a cover factor of 1500 or more, more preferably 2000 or more.
In the invention, in order to discourage the formation of capillaries, reduce the diameter of formed capillaries, and suppress water absorbability to achieve good drying properties, it is necessary that the yarn has a twist coefficient of 5100 or more, preferably 7000 or more, and more preferably 10000 or more. In the case where water-repellent treatment is performed to also achieve high waterproofness, a twist coefficient of 25000 or less is preferable.
With respect to the thickness of individual yarns (single-yarn denier), greater thickness is more preferable for the purpose of discouraging the formation of a capillary structure or reducing the number of capillaries to reduce water absorbability, etc. Meanwhile, in order to improve windproofness, the fabric structure needs to be dense, while for garment applications, the fabric needs to have a soft texture suitable for wearing. For these purposes, finer yarns are more preferable. In order to balance them, it is preferable that the yarn used in the invention has a single-yarn denier of 0.1 or more and 3.5 or less. It is more preferable to use the single-yarn denier of 0.3 or more and 2.2 or less.
Similarly, with respect to the thickness of the multifilament yarn used, a finer yarn is more preferable to densely weave a structure without forming a gap between the structures and increase waterproofness by water-repellent treatment, and a finer yam is more preferable also to achieve a soft wearing texture as a fabric for garments. Meanwhile, a thicker yarn is more preferable for the purpose of not forming a large number of capillaries between yarns. In order to balance them, in the invention, a yarn having a thickness of 30 denier or more and 150 denier or less is preferable. A yarn having a thickness of 50 denier or more and 100 denier or less is the most preferable.
With respect to the yarn shape, as compared with a filament type, a textured-yarn type is more preferable because such a yarn is more disordered and less likely to form a capillary structure. In addition, in order to obtain water repellency resistant to rubbing, it is necessary to form a rigid, fine irregularity structure according to the yarn diameter, which is not broken by rubbing. In the invention, it has been found that a twisted yarn is preferable to form a rigid, fine irregularity structure. In view of this, a filament having a greater single-yarn denier is more preferable. The single-yarn denier is preferably within a range of 0.3 or more, more preferably 0.4 or more, and most preferably 0.9 or more.
In order to obtain water repellency and waterproofness using the low air-permeable high-density woven fabric of the invention, water-repellent treatment is necessary, but no special water-repellent treatment is required. Water-repellent treatment may be performed in a usual manner using fluorine-based or silicone-based water repellent agent that has been used conventionally. Further, there is no limitation on the combined use of an antistatic agent or the like as necessary. For implementation, considering that it is high-density woven fabric, and further a high twisted multifilament yarn is used, etc., it is natural to make efforts that have been made in the past or that a person skilled in the art would make, for example, the combined use of a penetrating agent to enhance the penetration of a water repellent agent, the reduction of the processing speed to increase the immersion time, etc. By performing such ordinary water-repellent treatment, water repellency and a waterproofness of 200 mm or more are obtained.
In the evaluation of the rub resistance of water repellency mentioned below, it has been found that a product of the invention has highly rub-resistant water repellency, which has not been seen in a water-repellent, high-density woven fabric of prior art. This is likely to be because due to the coming and going of filaments caused by twisting (caused by spinning), a rigid, fine irregularity structure 3b is formed in the yarn according to the diameter of single-yarn filaments forming the multifilament yarn, and such a rigid, fine irregularity structure 3b is directly formed on the surface of the woven fabric (see
As multifilament yarns, multifilament yarns of synthetic fibers, semi-synthetic fibers, and regenerated fibers are all usable in the invention. However, in order to form a water-repellent, low air-permeable high-density woven fabric by water-repellent treatment, hydrophobic multifilament yarns are preferable. In particular, it is preferable to use polyester-based multifilament yarns, polyamide-based multifilament yarns, and polypropylene-based multifilament yarns.
Products of embodiments of the invention were evaluated and measured as follows.
1. Water repellency was evaluated in accordance with the spray method of JIS L 1092 (equivalent to ISO 4920).
Water is sprayed, and the degree of repellency against the wetting of the cloth surface is examined and rated on 5-point scale: “Levels 1, 2, 3, 4, and 5”. Level 5 is excellent.
2. The rub resistance of water repellency was evaluated as follows. Drops of 0.3 cc of water were placed on a woven fabric, and the portion having the water drops was strongly and horizontally rubbed with a thick chopstick made of bamboo. The evaluation was made based on the number of times until the drops stopped moving on the woven fabric (until traces of water drops were formed).
3. Water-pressure resistance was measured in accordance with the low-water-pressure method of JIS L 1092A (equivalent to ISO 811).
4. Air-permeability was measured in accordance with the fragile method of JIS L 1096 (equivalent to ISO 9237).
5. The cover factor in the warp direction was calculated as [the number of warp yarns per inch]×√
6. The cover factor in the weft direction was calculated as [the number of weft yarns per inch]×√
7. The cover factor of the entire woven fabric was calculated as the sum of the cover factor in the warp direction and the cover factor in the weft direction.
8. Water absorbability was evaluated as follows. A 10 cm×10 cm woven fabric was immersed in water, then sandwiched between newspapers and lightly pressed to remove excessive moisture, and weighed. The evaluation was made based on water absorption per fabric weight.
9. Drying properties were evaluated as follows. Immediately after the measurement of water absorption, the woven fabric was spin-dried in a spin-dryer of a National washing machine (NA-W 45A1) for 5 minutes. The evaluation was made based on the resulting water absorbability.
10. The number of twists is shown as the number of twists per meter (turns/M).
11. The twist coefficient of a yarn was calculated as [the number of twists per meter (turns/M)]×√
Hereinafter, the invention will be described in detail with reference to Examples and Reference Examples.
A woolly filament yarn (single-yarn denier 1.04) of 75 denier/72 filaments was twisted 2000 turns/M, and the resulting high twisted yam was used as the warp and weft. The fabric woven by the yams (an S-twist yarn was used as the warp, and an S-twist yarn and a Z-twist yarn were alternately used as the weft), was scoured, relaxed, dyed, and finished in a usual manner to give a low air-permeable high density warp mat plain-woven fabric of this reference example. This reference product had a warp density of 216 yarns per inch and a weft density of 86 yarns per inch. As a result of calculation, the twist coefficient of the high twisted multifilament yarns was 17321, and the cover factor of the entire woven fabric was 2615.
For comparison, the same woolly filament yarn (single-yam denier 1.04) of 75 denier/72 filaments as in this reference example was used. As the warp, the yarn was weakly twisted 300 T/M to such a degree that problems in weaving would be avoided. Meanwhile, as the weft, the yarn was used in the form of a nontwisted yarn having no twist. The fabric woven by the yams was scoured, relaxed, and dyed in a usual manner to give a high-density plain-woven fabric for comparison (hereinafter, Comparative Example 1). The woven fabric of Comparative Example 1 had a warp density of 132 yarns per inch and a weft density of 102 yarns per inch.
As a result of calculation, the twist coefficient of the warp yarn was 2598, the twist coefficient of the weft yarn was 0, and the cover factor of the entire woven fabric was 2026.
The following Table 1 shows the water absorbability and drying properties of the reference product and the comparative product.
It was shown that as compared with Comparative Example 1, Reference Example 1 has lower water absorbability and better drying properties.
The woven fabrics of Reference Example 1 and Comparative Example 1 were each subjected to water-repellent treatment with a fluorine-based water repellent agent (Asahi Guard AG-710, manufactured by Asahi Glass Co., Ltd.; a 7% aqueous solution was used) in a usual manner and then calendered to give Example 1 and Comparative Example 2. The following Table 2 shows the water-pressure resistance, water repellency, and rub-resistant water repellency of Example 1 and Comparative Example 2.
It was shown that in Example 1, rub-resistant water repellency. which is novel water repellency, is much higher than in Comparative Example 2.
In place of the woolly filament yarn (single-yarn denier 1.04) of 75 denier/72 filaments used in Reference Example 1, a woolly filament yarn (single-yarn denier 0.52) of 75 denier/144 filaments was S-twisted 2000 T/M, and the resulting high twisted textured yarn was used as the warp, while the same yarn as used for the warp was twisted 1500 T/M, and the resulting S-twist and Z-twist high twisted textured yarns were alternately used as the weft. The fabric woven by the yams was scoured, relaxed, dyed, and finished in the same manner as in Reference Example 1 to give a low air-permeable high-density warp mat plain-woven fabric of Reference Example 2. The woven fabric of Reference Example 2 had a warp density of 224 yarns per inch and a weft density of 84 yarns per inch. As a result of calculation, the twist coefficient of the warp high twisted multifilament yarn was 17321, the twist coefficient of the weft high twisted multifilament yarns was 12990, and the cover factor of the entire woven fabric was 2667. The following Table 3 shows the water absorbability and drying properties of Reference Example 2 and Comparative Example 1.
I was shown that in Reference Example 2, the single-yarn denier is smaller than in Reference Example 1, and thus water absorbability is slightly higher. Accordingly, drying properties are slightly lower than in Reference Example 1 but are better than in Comparative Example 1.
The woven fabric obtained in Reference Example 2 was subjected to water-repellent treatment and calendering in the same manner as in Example 1 to give a water-repellent woven fabric of Example 2. The following Table 4 shows the water-pressure resistance, water repellency, and rub-resistant water repellency of Example 2. For comparison, the same woven fabric as of Comparative Example 2 in Example 1 was used.
It was shown that in Example 2, the single-yarn denier is smaller than in Example 1, and thus improvement in water-pressure resistance is seen. In addition, rub-resistant water repellency is much higher than in Comparative Example 2.
A polyester filament yarn (single-yarn denier: 1.04) of 50 denier/48 filaments was twisted 2500 turns/M, and the resulting high twisted yarn was used as the warp and weft. The fabric was woven by the yams (an S-twist yarn was used as the warp, and an S-twist yarn and a Z-twist yarn were alternately used as the weft) in a usual manner to give a warp mat plain-woven fabric having a warp density of 235 yarns per inch and a weft density of 105 yarns per inch. The woven fabric was scoured, relaxed, and dyed by an ordinary dyeing method for polyester fabrics, then subjected to water-repellent treatment with a fluorine-based water repellent agent (Asahi Guard AG-710, manufactured by Asahi Glass Co., Ltd.; a 7% aqueous solution was used) in a usual manner, and further calendered to give a water-repellent, low air-permeable high-density woven fabric of Example 3.
The woven fabric of Example 3 had a warp density of 265 yarns per inch and a well density of 115 yarns per inch. The twist coefficient of the high twisted multifilament yarns used in this product of the example was 17678, and the cover factor of the entire woven fabric of this product of the invention was 2686. Air-permeability was 9.6 cc/cm2/sec. The weight of the woven fabric per square meter was 115 g.
For comparison, a woolly filament yarn (single-yarn denier: 1.04) of 75 denier/72 filaments in the form of a nontwisted yarn having no twist, was used as the warp and weft to give a warp mat plain-woven fabric having a warp density of 198 yarns per inch and a well density of 85 yarns per inch. The woven fabric was processed in the same manner as in Example 3 to give a water-repellent, low air-permeable high-density woven fabric for comparison (Comparative Example 3). The woven fabric of Comparative Example 3 had a warp density of 211 yarns per inch and a weft density of 91 yarns per inch. The twist coefficient of the warp and well multifilament yarns used herein was 0, and the cover factor of the entire woven fabric was 2615. The weight of the woven fabric per square meter was 115 g, and air-permeability was 0.3 cc/cm2/sec. The following Table 5 shows the water-pressure resistance, water repellency, rub-resistant water repellency, and drying properties of Example 3 and Comparative Example 3.
In Example 3, rub-resistant water repellency, which is novel water repellency, is much higher than in Comparative Example 3. In addition, drying properties are also much better than in Comparative Example 3.
A woolly polyester filament yarn (single-yarn denier 0.35) of 50 denier 44 filaments was twisted 1800 turns/M, and the resulting high twisted yarn was used as the warp, while a woolly polyester filament yarn (single-yarn denier 0.35) of 50 denier/144 filaments was twisted 2500 turns/M, and the resulting high twisted yarn was used as the weft. The fabric was woven by the yams (an S-twist yarn was used as the warp, and an S-twist yarn and a Z-twist yarn were alternately used as the weft) in a usual manner to give a warp mat plain-woven fabric having a warp density of 253 yarns per inch and a weft density of 107 yarns per inch. By the method described in Example 3, the woven fabric was scoured, relaxed, dyed, subjected to water-repellent treatment, and then calendered to give a water-repellent, low air-permeable high-density woven fabric of Example 4. The woven fabric of Example 4 had a warp density of 268 yams per inch and a weft density of 117 yarns per inch. The twist coefficients of the warp and weft high twisted multifilament yarns used in this product of the example were 12728 and 17678, respectively, and the cover factor of the entire woven fabric was 2722. In Example 4, rub-resistant water repellency, which is novel water repellency, was as excellent as 200 or more.
A woolly polyester filament yarn (single-yarn denier 0.35) of 50 denier/144 filaments was twisted 1800 turns/M, and the resulting high twisted yarn was used as the warp, while a woolly polyester filament yarn (single-yarn denier: 2.50) of 30 denier/12 filaments was used as the weft. The fabric was woven by the yams (an S-twist yarn was used as the warp) in a usual manner to give a warp mat plain-woven fabric having a warp density of 253 yarns per inch and a weft density of 127 yarns per inch. By the method described in Example 3, the woven fabric was scoured, relaxed, dyed, subjected to water-repellent treatment, and then calendered to give a water-repellent, low air-permeable high-density woven fabric of Example 5. The woven fabric of Example 5 had a warp density of 268 yarns per inch and a weft density of 139 yarns per inch. The twist coefficient of the warp high twisted multifilament yarn used herein was 12728, and the twist coefficient of the weft was 0. The cover factor of the warp was 1895, the cover factor of the weft was 761, and the cover factor of the entire woven fabric was 2656. As a result of calculation from the proportion of the cover factor of the warp to the total cover factor and also from the woven fabric structure, the percentage of the warp high twisted yarn to the surface area of the woven fabric was 83%. In Example 5, rub-resistant water repellency, which is novel water repellency, was as excellent as 200 or more.
The low air-permeable high-density woven fabric according to the invention is a low air-permeable woven fabric having low water absorbability and excellent drying properties, and also has excellent rub-resistant water repellency. Therefore, the woven fabric can be applied to a wide variety of fields including not only the field of garments, such as general garments, uniform garments, and garments for sports, but also the field of materials, such as tent fabrics and umbrella fabrics. In particular, the woven fabric has novel rub-resistant water repellency, which is resistant to rubbing. Therefore, it is useful as a novel water-repellent functional product in the field of sports or the field of uniforms, where water repellency is needed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-015989 | Jan 2012 | JP | national |
