JP2006161237A - Water repellent and breathable reversible woven or knitted fabric and method for producing the same - Google Patents

Abstract

[PROBLEMS] To provide a repellency that, when used as a garment, has a breathing performance that quickly responds to changes in humidity from the inside of the garment, reversibly changes the air permeability, and a water repellency that prevents moisture from entering from the outside of the garment. A water-breathable reversible woven or knitted fabric is provided.
SOLUTION: A woven or knitted fabric containing 30 wt% or more of swellable conjugate fiber in which a high swellable component and a low swellable component are combined on a side-by-side basis and provided with a water repellent, the water repellency of the woven or knitted fabric Is a water repellent breathable reversible woven or knitted fabric having a degree of air permeability of 10% or more, and a highly swellable component and a low swellable component are combined side by side. A woven or knitted fabric containing a swellable conjugate fiber is obtained by further squeezing after water-repellent processing.
Air permeability change amount (%) = [(wet air permeability (B) −initial air permeability (A)) / initial air permeability (A)] × 100
[Selection figure] None

Description

  The present invention relates to a woven or knitted fabric having water repellent ventilation reversibility and a method for producing the same.

  Many functional materials have been developed in the past. For functional products, fiber materials, fabric structures such as woven fabrics and knitted fabrics, functional post-processing, etc., or a combination thereof are used to express even higher functionality. Development is actively underway. In recent years, proposals for new functional materials have evolved to be more complex and more advanced, and in clothing, there have been many proposals for so-called dynamic functionality in which functionality changes according to changes in the wearing environment. An example is a proposal of a heat storage material that seeks to improve heat retention according to the amount of light energy absorbed.

  However, fashion trends and consumer needs in recent years have become extremely diversified and sophisticated, and in order to provide functional materials in line with consumer demands, further improvements in texture and specialized functionality are required. A proposal is needed. As one of the specialized functions, there is a function of adjusting the temperature and humidity in the clothes, and so-called breathing clothes are desired. This breathing garment reversibly changes the breathability of the garment in response to dynamic changes in the garment temperature, humidity, moisture, etc., and controls the temperature and humidity in the garment to constantly adjust it to a comfortable state. It is.

  In response to such a demand for breathable clothes, some ventilation reversible woven or knitted fabrics using fiber materials that reversibly change according to moisture and moisture have been proposed. For chemical fibers and synthetic fibers, there has been proposed a woven or knitted fabric using acetate fibers whose air permeability changes using a material whose crimp rate changes according to humidity (see Patent Document 1). There has also been a proposal using a composite fiber of modified polyethylene terephthalate and nylon (see Patent Document 2).

  In these breathable reversible knitted and knitted fabrics, a conjugate fiber material having a high moisture absorption and moisture absorption / release property is used to quickly respond to changes in moisture and moisture and reversibly change the breathability. ing. These breathable reversible woven and knitted fabrics absorb moisture and sweat when sweating during intense exercise, and the woven stitches expand and breathability increases, eliminating the feeling of stuffiness and stickiness in clothing and comfort. Is increased.

  However, when these breathable reversible woven and knitted fabrics are used as clothes, not only moisture and sweat from the inside of the clothes, but also a large amount of moisture from the outside such as rain, the woven stitches expand, so a lot of moisture There are problems such as easy penetration into clothes and further reduction in heat retention due to increased air permeability.

JP 2002-180323 A JP 2003-41462 A

  The object of the present invention is to solve such problems in the prior art, and when it is used as a garment, it can respond quickly to changes in humidity from the inside of the garment and reversibly change the air permeability. Another object of the present invention is to provide a water-repellent and breathable reversible woven or knitted fabric that has both water-repellent properties that prevent moisture from entering from the outside of the garment.

The first gist of the present invention is a woven or knitted fabric comprising 30% by weight or more of a swellable conjugate fiber in which a high water swellable component and a low water swellable component are combined side-by-side and provided with a water repellent. The water-repellent breathable reversible woven or knitted fabric is characterized in that the water-repellent degree of the woven or knitted fabric is grade 3 or more and the air permeability change amount of the woven or knitted fabric represented by the following formula is 10% or more. .
Air permeability change amount (%) = [(wet air permeability (B) −initial air permeability (A)) / initial air permeability (A)] × 100
The initial air permeability is the air permeability of the woven or knitted fabric at 25 ° C. and 65% RH when the moisture content is balanced, and the air permeability when wet is dehydrated and air-dried after immersing the woven or knitted fabric in water for 30 minutes. The air permeability when the rate is 25 ° C. and 50 wt%.
The second gist of the present invention is that a woven or knitted fabric comprising 30% by weight or more of a swellable conjugate fiber in which a high water swellable component and a low water swellable component are combined side by side is used. The water-repellent breathable reversible woven or knitted fabric is characterized in that after the water-repellent processing as described above, further squeezing processing is performed.

  The woven or knitted fabric of the present invention, when used as a garment, has an effect of automatically adjusting the temperature and humidity inside the garment when sweating due to intense exercise, etc., and also accelerates drying of the garment by water repellent treatment on the fiber surface, and further rains. By preventing the ingress of moisture from the outside such as time, the body temperature is prevented from decreasing due to excessive ventilation, and there is no stuffiness or stickiness.

  The woven or knitted fabric of the present invention is required to be composed of 30 wt% or more of a swellable conjugate fiber in which a high water swellable component and a low water swellable component are combined side by side. When the swellable conjugate fiber is less than 30 wt%, the change in the weave stitch due to the swellable conjugate fiber due to humidity and moisture becomes small, and a sufficient change in air permeability cannot be obtained. The highly water swellable component constituting the swellable conjugate fiber of the present invention is a highly swellable component having a water swell degree of preferably 30 to 200%, more preferably 40 to 100%, and a low water swellable component. Is a low water swellable or non-water swellable component having a water swelling degree of 20% or less, preferably 10% or less. The swellable conjugate fiber with a combination of components having different swelling properties is excellent in moisture absorption, water absorption and quick drying, and reversible and large change in fiber shape during moisture absorption, water absorption and drying, and durability. Will also be excellent. In addition, the water swelling degree of each component of a conjugate fiber is a numerical value when it measures with the fiber of each single component.

  In addition, the composite ratio of the high water swellable component and the low water swellable component in the swellable conjugate fiber is preferably 20:80 to 80:20, and more preferably 40:60 to 75:25. More preferably, it is the range. If the low water swellable component is less than 20 wt% or more than 80 wt%, the shrinkage does not occur sufficiently and it is insufficient to cause a reversible fiber shape change. Further, in order to cause a difference in shrinkage between the components, the difference in the degree of water swelling is preferably 20% or more, more preferably 30% or more.

  The high water swellable component in the swellable conjugate fiber repeats the phenomenon of stretching when swollen and shrinking when not swollen, but because it is bonded to the low water swellable component side-by-side, it swells with high water during moisture absorption and water absorption. The crimp of the fiber disappears due to the stretching of the active ingredient side, the crimp is caused by the shrinkage of the highly swellable ingredient during drying, and the disappearance of the crimp form and the expression of the crimp form are reversibly repeated during moisture absorption, water absorption and drying. As a result, the air permeability of the woven or knitted fabric reversibly changes.

  As the swellable conjugate fiber in the woven or knitted fabric of the present invention, specifically, a cellulose-based swellable conjugate in which two components, one of which is highly water-swellable cellulose and the other is cellulose acetate, are combined side by side. Fiber is preferred. In the cellulose-based swellable conjugate fiber, cellulose having an acetylation degree of 0% may be a high water swellable component, and cellulose acetate having an acetylation degree of 56.2% or more and 62.5% or less may be a low water swellable component. More preferred.

  This cellulose-based swellable conjugate fiber is obtained by, for example, subjecting a precursor fiber in which cellulose acetate having an average degree of substitution of less than 2.60 and cellulose acetate having an average degree of substitution of 2.76 or more to the side-by-side is deacetylated with an alkali. Can be obtained. Cellulose acetate of each substitution degree is deacetylated by deacetylation treatment with alkali, but only low-substitution cellulose acetate is deacetylated because low-substitution cellulose acetate is more easily deacetylated. Deacetylation is performed under the following conditions. By this deacetylation treatment, the low-substitution cellulose acetate component of the precursor fiber becomes cellulose with an acetylation degree of 0% or an acetylation degree of 0%, and the difference in water swellability with other components increases. A reversible shape change of the fiber due to humidity and moisture can be obtained. The alkali treatment for deacetylation may be performed in the state of a yarn or a woven or knitted fabric, but is more preferably performed after forming the woven or knitted fabric in terms of handling.

  Furthermore, in the woven or knitted fabric of the present invention, in addition to the swellable conjugate fiber, other constituent fiber materials may be included within a range not exceeding 70 wt%. When other constituent fiber materials are included, any composite means may be used, but it is preferably included as a composite yarn with a swellable conjugate fiber. As other constituent fiber materials, thermoplastic fibers excellent in chemical resistance such as alkali are preferable, and also from the viewpoint of the heat setting property for reinforcing the fiber strength and improving the shape stability of the woven or knitted fabric. It is preferably a fiber.

  The thermoplastic fiber is not particularly limited, but is preferably a polyester fiber, a polyamide fiber or the like, and may be a crimped yarn form. In addition, the cross-sectional shape of the thermoplastic fiber is not particularly limited, and a cross-sectional shape such as a triangular shape, a circular shape, a flat shape, and a Y shape is appropriately selected in consideration of the texture, gloss, and the like of the obtained woven or knitted fabric. Furthermore, the single fiber fineness, fineness unevenness, dyeing characteristics and the like of the thermoplastic fiber are not particularly limited.

  The thermoplastic fiber is composed of two kinds of polymers having different melt viscosities and compositions, two kinds of polymers such as polyester and polyacrylonitrile, polyester and polyamide, and a composite ratio of 80:20 to 20:80, preferably 60:40 to More preferably, it is a conjugate fiber bonded to the side by side of 40:60. That is, since the conjugate fiber has crimp characteristics, when the swellable conjugate fiber is stretched by moisture absorption or contracted by moisture release, the effect of making it difficult to hinder the movement of the fiber is high.

  As a means for combining thermoplastic fibers, methods such as twisting, covering, air fluid processing, false twisting, and the like can be used. Among these, air fluid processing is preferable as a preferable method. That is, if the degree of freedom of the swellable conjugate fiber is large, the air permeability effect in the woven or knitted fabric is also large, so that the yarn form is formed by elongating the thermoplastic fiber with respect to the swellable conjugate fiber by air fluid processing. It is preferable.

  Further, the woven or knitted fabric of the present invention is provided with a water repellent to the woven or knitted fabric to obtain a change in air permeability due to moisture while preventing entry of moisture from the outside into the woven or knitted fabric when used as a garment. The degree must be 3rd or higher. If the water repellency is less than the third grade, the weave stitches are rapidly expanded due to moisture from the outside, moisture penetrates into the interior, and the excessive ventilation effect is produced, resulting in a problem of reduced heat retention. . Examples of the water repellent applied to the woven or knitted fabric include a silicon-based water repellent and a fluorine-based water repellent.

Furthermore, in the woven or knitted fabric of the present invention, the air permeability change amount of the woven or knitted fabric represented by the following formula needs to be 10% or more.
Air permeability change amount (%) = [(wet air permeability (B) −initial air permeability (A)) / initial air permeability (A)] × 100
When the change in air permeability is less than 10%, the expression of the crimped form of the swellable conjugate fiber due to humidity is reduced, and the change in the form of the fiber due to disappearance is reduced, and the air permeability at the woven stitch is reduced, resulting in stuffiness and stickiness. The comfort is impaired by the feeling.

  The initial air permeability of the present invention refers to the air permeability when the woven or knitted fabric is measured at 25 ° C. and 65% RH when the moisture content is balanced. The wet air permeability is dehydrated after the woven or knitted fabric is immersed in water for 30 minutes. The air permeability measured when air-dried and the moisture content of the woven or knitted fabric is 25 ° C. and 50 wt% is measured. Air permeability when wet is the air permeability assuming practical use such as during sweating exercise in clothing, and the measurement conditions are moisture content that has little effect on measurement accuracy due to excess moisture while the clothes are wet. As a condition, the moisture content of the woven or knitted fabric was set to 25 ° C. and 50 wt%.

The woven or knitted fabric of the present invention can be produced, for example, as follows.
That is, the woven or knitted fabric of the present invention is a woven or knitted fabric comprising 30% by weight or more of a swellable conjugate fiber in which a high water swellable component and a low water swellable component are combined side by side. After being water-repellent processed, it is manufactured by further squeezing. Specifically, a woven or knitted fabric composed of 30% by weight or more of precursor fibers in which two types of cellulose acetates having different degrees of substitution are compounded side by side is alkali-treated, and the precursor fibers are deacetylated to swell the conjugate. The woven or knitted fabric is manufactured by subjecting it to a gate fiber and subjecting the woven or knitted fabric to a water repellent degree of 3 or more, followed by further squeezing.

  Further preferably, the precursor fiber is a fiber in which cellulose acetate having an average degree of substitution of less than 2.60 and cellulose acetate having an average degree of substitution of 2.76 or more are combined side by side. In the deacetylation treatment with alkali, It is preferable to perform alkali treatment under the same conditions so that only the low-substituted cellulose acetate of the precursor fiber is selectively deacetylated, and the conditions for causing selective deacetylation are the average degree of substitution of cellulose acetate used Depending on the proportion of the precursor fiber, etc., the alkali treatment conditions such as the concentration, temperature, and time at which the low-substituted cellulose acetate is deacetylated are determined and set. By the alkali treatment of the precursor fiber under the conditions for such low-substituted cellulose acetate, the low-substituted cellulose acetate is easily deacetylated to become cellulose having an acetylation degree of 0% or very close to acetylation degree of 0%. Thus, the cellulose acetate exhibits high water swellability, and the highly substituted cellulose acetate exhibits low or non-water swellability while maintaining a high degree of acetylation with little or no deacetylation.

  The water-repellent processing can be performed using a known water-repellent agent such as a silicon-based water-repellent agent or a fluorine-based water-repellent agent, and a generally employed padding method, spray method, or the like. In order to prevent the entry of excessive moisture from the outside, it is necessary to water-repellent the water repellency to grade 3 or higher. If the water repellency is 3 or more, the processing conditions in the water repellent processing are as follows: the type of water repellent, the amount applied to the woven or knitted fabric, the density of the woven or knitted fabric, the structure, the processing temperature, the time, etc. You can choose arbitrarily.

Further, in the present invention, it is necessary to perform a squeezing process after the water repellent process. In water-repellent processing, the water-repellent agent penetrates and adheres to the gaps between the single fibers and the interlaced points of the woven or knitted fabric, and the movement between the fibers, that is, the degree of freedom of the fibers is hindered. Thus, the constrained state between the fibers is released, and the breathable reversible change due to the change in the fiber shape of the swellable conjugate fiber due to humidity is easily performed. For example, a tumbler or cam fit is used for the squeezing process. Depending on the density and structure of the woven or knitted fabric, it is preferable that at least the woven or knitted fabric is initially measured at 25 ° C. and 65% RH at the time of moisture content equilibrium. The conditions such as temperature, time, impact load, etc. are selected so that the air permeability is 120 cm ³ / cm ² / sec.

  Hereinafter, the present invention will be specifically described by way of examples. Each characteristic value was measured by the following method.

(1) Water repellency measured according to JIS L1092 general test method (spray test).

(2) In an environment variable chamber with an air permeability of 20 ° C. and 65% RH, the measurement was performed using an air permeability tester FX3300 manufactured by Textex Co., Ltd. according to JIS L1018 general test method (Fragile test). The initial air permeability (A) in the present invention means the air permeability (cm ³ / cm ² / sec) when the woven or knitted fabric is measured at 25 ° C. and 65% RH at the time of moisture content equilibrium. ) Is the air permeability (cm ³ / cm ² / sec) when the woven or knitted fabric is immersed in water for 30 minutes, dehydrated and air-dried, and measured when the moisture content of the woven or knitted fabric is 25 ° C. and 50 wt%. Say. The re-drying air permeability (A1) is used to confirm reversibility when the woven or knitted fabric is wetted and then dried again, and is air-dried to a moisture content equilibrium state of 25 ° C. and 65% RH. The air permeability (cm ³ / cm ² / sec) was determined.

(3) Degree of water swell The measurement of the degree of water swell of each component in the swellable conjugate fiber was measured as follows, using fibers each composed of a single component. In this example, the measurement was performed using fibers that are composed of single components of cellulose acetates having different degrees of substitution, and were deacetylated by alkali treatment under the same conditions as shown in the examples.
The cross section of the fiber was photographed with a microscope to determine the cross sectional area (a), and water was added dropwise on the preparation to swell the fiber, and the cross sectional area (b) after 15 minutes was determined. The degree of water swelling was calculated from the following formula by the cross-sectional area ratio.
Water swelling degree (%) = ((b−a) / a) × 100

(4) Degree of substitution
The degree of acetylation was measured according to JIS L1013A method, and the degree of acetate substitution with cellulose was determined from the following formula.
Degree of acetylation = [(60 × degree of substitution) / (158 + 43 × degree of substitution + 1 × (3-degree of substitution))] × 100

(5) Feeling of stuffiness and stickiness A run shirt was made from the obtained woven or knitted fabric and subjected to a wearing test. The feeling of stuffiness and stickiness after running for 1 hour was sensorially evaluated by the wearer.

Example 1
Acetate conjugate fibers (84 dtex / 30 filaments) obtained by composite spinning of cellulose diacetate having an average degree of substitution of 2.41 and cellulose triacetate having an average degree of substitution of 2.91 in a side-by-side type having a weight ratio of 50:50; , Using polyester conjugate fiber (Made by Rayon, Rasina 33 dtex / 12 filament) obtained by composite spinning of two kinds of polyesters having different heat shrinkability side by side, twist number 1800 T / m, 80 ° C., 40 minutes Heat setting with steam was performed under the conditions to produce a twisted yarn.

  Using this twisted yarn, a woven fabric was woven in a warp double weave structure with a warp density of 45/4 pieces and a weft density of 115 pieces / 2.54 cm. The obtained woven fabric was subjected to an alkali treatment in a treatment bath having a 1% by weight sodium hydroxide aqueous solution and a bath ratio of 1: 100 at a temperature of 60 ° C. for 15 minutes, and then at a dyeing temperature of 130 ° C. and a dyeing time of 30 minutes. Dyeing was performed using a disperse dye. The original acetate conjugate fiber in the resulting dyed fabric is composed of a highly water-swellable component having a water swelling degree of 60%, in which the cellulose diacetate component is significantly deacetylated by alkali treatment, and water in which the cellulose triacetate component is hardly deacetylated. It became a low water swellable component with a swelling degree of 9%, and it became a side-by-side swellable conjugate fiber in which these two components were constituted at a weight ratio of 45:55.

The obtained woven fabric was impregnated with a fluorine water repellent by a padding method using a fluorine water repellent (a water repellent comprising a perfluoroalkyl acrylate copolymer), squeezed with a mangle, and then at 170 ° C. for 3 minutes. It was heat-treated and subjected to water repellent treatment under the condition that 5 wt% of the fluorine-based water repellent was adhered. After that, further squeezing process was performed with a tumbler to release the restraint between the fibers. Table 1 shows the evaluation results of the obtained woven fabric. In addition, the unit of the air permeability in Table 1 is cm ³ / cm ² / sec.

(Example 2)
A twisted yarn obtained by adding 1200 T / m of the acetate conjugate fiber in Example 1 to the twisted yarn of 1200 T / m in the yarn configuration used in Example 1 is prepared, and using this twisted twisted yarn, warp A woven fabric was prepared in a warp yarn with a 1: 1 arrangement in a warp double weave structure with a warp density of 48/4 pieces and a weft density of 130 pieces / 2.54 cm. Thereafter, the woven fabric was subjected to alkali treatment, dyeing, water repellent treatment and squeezing treatment in the same manner as in Example 1. Table 1 shows the evaluation results of the obtained woven fabric.

(Comparative Example 1)
In Example 1, a woven fabric was obtained without water-repellent processing by the padding method without squeezing with a tumbler. Table 1 shows the evaluation results of the obtained woven fabric.

(Comparative Example 2)
In Example 2, a woven fabric was obtained without water-repellent processing by a spray method instead of the padding method and without squeezing by a tumbler. Table 1 shows the evaluation results of the obtained woven fabric.

(Example 3)
Acetate conjugate fiber (84 dtex / 20 filament) obtained by composite spinning of cellulose diacetate having an average substitution degree of 2.41 and cellulose triacetate having an average substitution degree of 2.91 in a side-by-side type having a weight ratio of 50:50; Polyester fiber (33 dtex / 12 filament) was used, and air fluid processing was performed to create a mixed fiber. Using this blended yarn, a reversible structure with a surface layer of polyester fiber (110 dtex / 24 filament), an intermediate layer tack portion of polyester fiber (56 dtex / 24 filament), and a back layer made of this blended yarn. did. Thereafter, the knitted fabric was subjected to alkali treatment, dyeing, water-repellent processing and squeezing in the same manner as in Example 1. The evaluation results of the obtained knitted fabric are shown in Table 1.

(Comparative Example 3)
In Example 3, a woven fabric was obtained without water repellency by spraying instead of padding and without squeezing with a tumbler. Table 1 shows the evaluation results of the obtained woven fabric.

The woven or knitted fabric of the present invention, when used as a garment, has an effect of automatically adjusting the temperature and humidity inside the garment when sweating due to intense exercise, etc., and also accelerates drying of the garment by water repellent treatment on the fiber surface, and further rains. Outdoor clothing made of high-density woven and knitted fabrics such as windbreakers because it prevents moisture from entering from the outside and prevents body temperature from being lowered due to excessive ventilation, and has no stuffiness or stickiness. Etc. can be suitably used.

Claims (4)

A woven or knitted fabric comprising a swellable conjugate fiber in which a high water swellable component and a low water swellable component are combined side by side in an amount of 30 wt% or more, and having a water repellent added thereto. A water-repellent breathable reversible woven or knitted fabric having a degree of grade 3 or higher and an air permeability change amount of the woven or knitted fabric represented by the following formula of 10% or more.
Air permeability change amount (%) = [(wet air permeability (B) −initial air permeability (A)) / initial air permeability (A)] × 100
The initial air permeability is the air permeability of the woven or knitted fabric at 25 ° C. and 65% RH when the moisture content is balanced, and the air permeability when wet is dehydrated and air-dried after immersing the woven or knitted fabric in water for 30 minutes. The air permeability when the rate is 25 ° C. and 50 wt%.   The water-repellent and breathable reversible woven or knitted fabric according to claim 1, wherein the swellable conjugate fiber is a fiber in which two components, one of which is cellulose and the other is cellulose acetate, are combined side by side.   A woven or knitted fabric composed of 30% by weight or more of a swellable conjugate fiber in which a high water swellable component and a low water swellable or non-water swellable component are combined side-by-side with a water repellency of grade 3 or higher. After that, a method for producing a water-repellent breathable reversible woven or knitted fabric, which is further squeezed. The swellable conjugate fiber is deacetylated with alkali under the condition that the precursor fiber in which two types of cellulose acetates with different degrees of substitution are compounded side-by-side is deacetylated with alkali. A method for producing a water-repellent and breathable reversible woven or knitted fabric according to claim 3.