Patent Application
20080132133
The present invention relates to a woven or knitted fabric and clothes containing crimped composite filaments and having an air permeability which increases when the fabric is wetted with water or, for example, sweat. Particularly, the present invention relates to a woven or knitted fabric comprising composite filaments comprising a polyester component and a polyamide component bonded together in a side-by-side or eccentric core-sheath type structure, and having manifested crimps. Moreover, the present invention relates to a woven or knitted fabric and clothes having an air permeability which reversibly and efficiently increases when the fabric is wetted with water, in comparison with that upon drying.
It has been known that a woven or knitted fabric containing crimped synthetic filaments can be used for sportswear such as skiwear, windbreakers and outdoor wear, and outerwear such as raincoats and men and women's coats, etc.
However, when the above-mentioned conventional woven or knitted fabric is wetted with water or, for example, by sweat, problems that the fabric sticks to the skin to make the wearer feel uncomfortable, and the drying speed is slow, occur.
In order to solve the above problems, an air-permeable self-adjusting type woven or knitted fabric having an air permeability that is increased by wetting with water and that is decreased by drying has been proposed. When one wears clothes prepared from the conventional woven or knitted fabric, and the clothes are wetted with sweat, the air permeability of the clothes increases so as to rapidly remove the water remaining in the clothes to dry the clothes. Moreover, the air permeability of the clothes decreases after drying to increase the warmth-retaining effect of the clothes. Therefore, good wearability of the clothes can always be maintained regardless of whether the wearer sweats or not.
For example, Japanese Unexamined Patent Publication (Kokai) No. 2003-41462 (Patent Reference 1) discloses an air permeable self-adjusting type woven or knitted fabric comprising composite filaments (A) in which a modified poly(ethylene terephthalate) containing a sulfonate group and a nylon are bonded together in a side-by-side type structure, and filaments (B) the dimensions of which do not substantially change even when the humidity changes. Although the air permeability of the woven or knitted fabric is reversibly increased upon wetting with water in comparison with that upon drying, an amount of change in air permeability is practically insufficient.
Furthermore, Japanese Unexamined Patent Publication (Kokai) No. 10-77544 (Patent Reference 2) discloses a woven or knitted fabric comprising 30% by weight or more of synthetic multifilaments yarn which is formed from a moisture-absorbent polymer (for example, copolymerized polyester polymers in which a hydrophilic compound is copolymerized and a polyether ester amide polymers) and which is one heat-treated so that the yarn has a twist multiplier of 6,800 to 26,000.
Still furthermore, Japanese Unexamined Patent Publication (Kokai) No. 2002-180323 (Patent Reference 3) discloses a woven or knitted fabric formed from cellulose acetate filaments (having a percentage of crimp less than 10% at a humidity of 95% RH or more, and a percentage of crimp of 15 to 20% and a number of crimps of 25/25.4 mm at a humidity of 65%, and a percentage of crimp of 20% or more at a humidity of 45% RH or less.
The woven or knitted fabrics disclosed in Patent References 1 and 2 exhibit an air permeability which increases upon absorbing moisture. However, the extent of the change in air permeability is practically insufficient and, thus, an air permeable self-adjusting woven or knitted fabric having a still larger change in air permeability has been desired.
Patent Reference 1 Japanese Unexamined Patent Publication (Kokai) No. 2003-41462
Patent Reference 2 Japanese Unexamined Patent Publication (Kokai) No. 10-77544
Patent Reference 3 Japanese Unexamined Patent Publication (Kokai) No. 2002-180323
An object of the present invention is to provide a woven or knitted fabric comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water and clothes containing the woven or knitted fabric, the woven or knitted fabric and clothes having an air permeability which increases to an adequately high degree for practical use upon being wetted with water in comparison with that upon drying.
The woven or knitted fabric of the present invention comprises a yarn comprising composite filaments formed from a polyester resin component and a polyamide resin component different from each other in thermal shrinkage and bonded together in a side-by-side structure or in an eccentric core-in-sheath structure, and has crimps manifested by heat treatment applied thereto, the crimped composite filaments being contained in a content of 10 to 100% by mass in the woven or knitted fabric, and satisfying the following requirement:
(DCF−HCF)≧10%
wherein DCF represents a percentage of crimp of a sample of crimped composite filaments taken from the woven or knitted fabric, determined by leaving the sample to stand for 24 hours in a test environment at a temperature of 20° C. at a humidity of 65% RH to dry and HCF represents a percentage of crimp of another sample of the taken crimped composite filaments, determined by immersing the other sample in water at a temperature of 30° C. for 2 hours, pulling up the sample from the water, holding the sample between a pair of filter paper sheets in the ambient atmospheric air at a temperature of 30° C. at a humidity of 90% RH within 60 sec after pulling up the sample, leaving the sample under a pressure of 0.69 mN/cm2 for 5 seconds to lightly wipe water from the sample, whereby the woven or knitted fabric exhibit an air permeability which increases when the fabric is wetted with water.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the polyester resin component comprises a modified polyester resin in which, 5-sodiosulfoisophthalic acid is copolymerized in an amount of 2.0 to 4.5 molar % based on the content of the acid component.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the yarn comprising the crimped composite filaments has a number of twists of 0 to 300 turns/m.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the woven or knitted fabric contains the crimped composite filaments and other filaments different from the crimped composite filaments.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the other filaments are selected from non-crimped filaments or filaments showing a difference in percentage of crimp DCF−HCFof 10% or less.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, when the woven or knitted fabric comprising the crimped composite filaments is subjected to determination of the stretchability of a stretchable woven fabric in accordance with JIS L1096, 8.14.1 (Method B, except that the load value applied to a sample woven or knitted fabric test piece is altered to 1.47 N, where the woven or knitted fabric is a woven fabric, a stretchability of the woven fabric in at least one direction selected from the warp direction and the weft direction is 10% or more, and where the woven or knitted fabric is a knitted one, the stretchability of the knitted fabric in at least one direction selected from the course direction and the wale direction is 10% or more.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the woven or knitted fabric comprising the crimped composite filaments has a multiply structure, and at least one ply thereof comprises the crimped composite filaments in an amount of 30 to 100 mass % based on the weight of the ply.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the woven or knitted fabric is a knitted fabric having a tubular knitted stitch, and the loop of the tubular knitted stitch is formed from a yarn comprising the crimped composite filaments and the other filaments.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the woven or knitted fabric is a woven fabric, the yarn containing composite filaments is a doubled yarn of the crimped composite filaments and the other or the warp filaments, and the warp and weft yarns or the warp or weft yarn of the woven fabric is constituted from a doubled yarn of the crimped composite filaments and the other filaments.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the yarns composed of the crimped composite filaments and the yarn composed of the other filaments are alternately arranged with one each other in at least one direction selected from the warp direction and the weft direction, or in at least one direction selected from the course direction and the wale direction.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, from the crimped composite filaments and the other filaments, a core-sheath composite yarn is formed, the core portion of the composite yarn is formed from the crimped composite filaments, and the sheath portion is formed from the other filaments.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the other filaments are selected from polyester filaments.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the woven or knitted fabric is one treated with a water-absorbing agent.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the woven or knitted fabric is one treated with a water-repellent treatment.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water, the woven or knitted fabric is dyed.
In the woven or knitted fabric of the present invention comprising crimped composite filaments and having an air permeability which increases when the fabric is wetted with water,
when a dried sample is prepared by leaving a test sample of the woven or knitted fabric to stand for 24 hours in an environment at a temperature of 20° C. at a humidity of 65% RH, separately a water-wetted sample is prepared by immersing a test sample of the woven or knitted fabric in water at a temperature of 30° C. for 2 hours, pulling up the test sample from the water, holding the test sample between a pair of filter paper sheets in the ambient atmospheric air at a temperature of 30° C. at a humidity of 90% RH within 60 seconds after pulling up the test sample, and leaving the test sample under a pressure of 490 N/m2 (50 kgf/m2) for 1 minute to lightly remove water from the test sample, and the air permeabilities of the dried sample and the water wetted sample are determined in accordance with JIS L 1096-1998, 6.27.1, Method A, (fragile type air permeability testing machine method) a rate of change in air permeability of the woven or knitted fabric calculated in accordance with the following equation:
Rate of change (%) in air permeability={[(Air permeability of water wetted sample)−(Air permeability of dried sample)]/(Air permeability of dried sample)}×100
is 30% or more.
Clothes comprising the woven or knitted fabric of the present invention comprising the crimped composite filaments and having dimensions which are reversibly enlarged when the fabric is wetted with water to increase the air permeability thereof.
In the clothes of the present invention, at least one of the flank, the side, the breast, the back and the shoulder of the clothes is formed from the woven or knitted fabric comprising the crimped composite filaments.
In the clothes of the present invention, each of the portions of the clothes formed from the woven or knitted fabric comprising the crimped composite filaments has an area of 1 cm2 or more.
In the clothes of the present invention, the woven or knitted fabric comprising the crimped composite filaments is selected from tubular knitted fabrics and mesh-like coarse woven or knitted fabrics.
The clothes of the present invention, are selected from outerwear, sportswear and underwear.
The crimped composite filaments contained in the woven or knitted fabric of the present invention have a characteristic property that the percentage of crimp of the filaments decreases 10% or more upon wetting with water in comparison with one upon drying. The woven or knitted fabric containing the crimped composite filaments therefore exhibits a significantly increased air permeability upon wetting with water in comparison with one upon drying. Accordingly, in the case where the woven or knitted fabric containing a crimped composite filaments of the present invention is used as a material for forming whole or a part of outerwear, sportswear or underwear, when the clothes a wearer wears are wetted with water, for example, due to wearer's sweating, the air permeability of the clothes increases, and the water component retained within the clothes is dried and released. When the clothes are thus adequately dried, the air permeability decreases, and the warmth retention is improved. The wearability is therefore always kept excellent, and the clothes contribute to the maintenance of wearer's good health.
The crimped composite filaments contained in the woven or knitted fabric of the present invention having an air permeability which increases when the fabric is wetted with water is formed from a polyester resin component and a polyamide component, and has a side-by-side type or an eccentric core-in-sheath type composite filament structure.
For a side-by-side type composite filament having, for example, an approximately circular cross-sectional profile as shown in
For a side-by-side type composite filament as shown in
For a side-by-side type composite filament having a cross-sectional profile as shown in
In
For an eccentric core-in-sheath type composite filament having a cross-sectional profile as shown in
The cross-sectional contour of a composite filament contained in the woven or knitted fabric of the present invention is not restricted to those as shown in
For a side-by-side type composite filament and an eccentric core-in-sheath type composite filament, the polyester resin component and the polyamide resin component are different in thermal shrinkage from each other. As a result, an amount of thermal shrinkage of the section 1 and one of the section 2 produced when the composite filament is heated, are different from each other, and crimp of the composite filament are manifested.
In the cross-sectional profile of the composite filament in the present invention, the mass ratio, of the section 1 to the section 2 that are bonded together, is preferably from 30:70 to 70:30, more preferably from 40:60 to 60:40.
The polyester resin component comprises a polycondensation product of an acid component comprising at least one aromatic dicarboxylic acid, and a diol component comprising at least one alkylene glycol.
The acid component preferably comprises terephthalic acid, as a major component. The diol component preferably contains, as a major component, ethylene glycol, propylene glycol, butylene glycol, etc. The polyester resin component preferably comprises, as a copolymerization component, a compound having at least one functional group selected from an alkali metal sulfonate group, an alkaline earth metal sulfonate group and a phosphonium salt group. That is, the polyester resin component preferably comprises a modified polyester, for example, a poly(ethylene terephthalate) copolymer, a poly(propylene terephthalate) copolymer or a poly(butylene terephthalate) copolymer containing, as a copolymerization component, an aromatic dicarboxylic acid having, as a functional group, the sulfonic acid salt group as mentioned above. The above compounds for copolymerization each having a sulfonic acid salt group contribute to improving an adhesive property of the polyester resin component thus obtained to the polyamide resin component.
The poly(ethylene terephthalate) copolymer modified with the copolymerization component containing a sulfonic acid salt group is particularly preferably used as the polyester resin component of the crimped composite filament for the woven or knitted fabric of the present invention, because it has an excellent flexibility and a low polymer price.
Examples of the aromatic dicarboxylic acid having a sulfonic acid salt group include 5-sodium sulfoisophthalic acid and its ester derivatives and 5-phosphnium isophthalic acid and its ester derivatives. Moreover, examples of the hydroxyl compound containing a sulfonate group include sodium p-hydroxybenzenesulfonate. Among these compounds, 5-sodium sulfoisophthalic acid is preferably used. The content of the above copolymerization component is preferably from 2.0 to 4.5 molar % based on a molecular amount of the acid component of the polyester polymer containing the copolymerization component. When the content of the copolymerization content is less than 2.0 mol %, the resultant composite filaments exhibits a sufficient crimping property, while the section composed of the polyester resin component and the section composed of the polyamide resin component may be separated at the interface between them from each other. Moreover, where the content of the above copolymerization component exceeds 4.5 molar %, and when the resultant undrawn composite filaments are drawn and heat-treated, crystallization of the section composed of the resultant polyester resin component insufficiently proceeds, and thus it becomes necessary to increase the drawing and heat treatment temperature, and the increased temperature causes breakages, of the resultant yarns, which often occur during the drawing and heat treatment procedures.
There is no restriction on the type of the polyamide resin used as the polyamide resin component as long as it has an amide bond in the principal chain and it has fiber forming property. Examples of the polyamide resin include nylon 4, nylon 6, nylon 66, nylon 46 and nylon 12. Among these resins, nylon 6 and nylon 66 are preferably used in the present invention in view of the excellent flexibility, its relatively low polymer price and the high stability in production step of the polyamide resin.
The polyester resin component and the polyamide resin component may be respectively, independently from each other and optionally contain at least one type of additives selected from pigments, delustering agents, stain-proofing agents, fluorescent brighteners, flame retardants, stabilizers, antistatic agents, light-resistant agents and UV absorbers.
There is no specific restriction on the thickness of individual filaments in the composite filaments and the number of individual filaments contained in one yarn. However, the thickness of the individual filaments is preferably in the range of from 1 to 10 dtex, more preferably from 2 to 5 dtex. The number of composite filaments contained in one yarn of the composite filaments is preferably from 10 to 200, more preferably from 20 to 100.
Furthermore, in the composite filaments contained in the woven or knitted fabric of the invention, the polyamide resin section formed from the polyamide resin component has a higher thermal shrinkage and a higher moisture absorption self-elongation than those of the polyester resin section formed from the polyester resin component.
Consequently, when the composite filaments usable for the present invention having a side-by-side or eccentric core-in-sheath type composite filament structure are heated, the polyamide resin section shrinks greater than the polyester resin section. As a result, the composite filament manifests a crimped structure wherein the resin section having a larger shrinkage amount is situated inside, and the resin section having a smaller shrinkage amount is situated outside. When the yarn containing a non-crimped composite filament is heated to manifest crimps in the resultant composite filaments, the resultant yarn containing crimped composite filaments has a higher bulkiness and a shorter apparent yarn length than those of the non-crimped composite filament yarn.
When a crimped composite filament used in the present invention is wetted with water, the polyamide resin section in the crimped composite filament absorbs a larger amount of water than that of the polyester resin section, and exhibits a larger self-elongation. (In general, the self-elongation of the polyester resin section caused by water wetting is close to zero.) As a result, the percentage of crimp of a water-wetted crimped composite filament becomes lower than that of a dried crimped composite filament; the apparent length of the water-wetted crimped composite filament becomes greater than that of the dried crimped composite filament. Moreover, when the water-wetted crimped composite filament is dried, the polyamide resin section is dehydrated and shrunk. However, because the polyester resin section has substantially no dimensional change, the percentage of crimp of the dried crimped composite filament recovers to the initial one, and the apparent length thereof recovers to the initial one.
As explained above, in the crimped composite filament contained in the woven or knitted fabric of the invention, the percentage of crimp decreases upon being wetted with water, and the apparent length of the filament increases. The percentage of crimp and the apparent length of the crimped composite filament recover the initial ones upon drying. In the woven or knitted fabric formed from yarns containing crimped composite filaments having the above properties, the percentage of crimp of the crimped composite filaments decreases upon being wetted with water. As a result, the length of the crimped composite filament-containing yarn increases; a gap between yarns in the woven or knitted fabric increases; the area of the fabric increases; and the air permeability of the fabric increases.
The air permeability of the woven or knitted fabric can be determined in accordance with JIS L 1096-1998, 6.27.1. A Method (Fragile type air permeability testing machine method).
In the woven or knitted fabric containing a crimped composite filaments of the present invention, it is important that the air permeability upon being wetted with water be higher than that upon drying. Preferably the air permeability upon being wetted with water is 30% or more, more preferably 80 to 500% higher than that upon drying.
A change (%) in air permeability is calculated from the following equation:
change (%) in air permeability=[(air permeability of a water wetted sample)−(air permeability of a dried sample)]/(air permeability of a dried sample)×100
wherein the dried sample is prepared by leaving a test sample of the woven or knitted fabric to stand for 24 hours in an environment at a temperature of 20° C. at a humidity of 65% RH, separately the water wetted sample is prepared by immersing a test sample of the woven or knitted fabric in water at a temperature of 30° C. for 2 hours, pulling up the test sample from the water, holding the test sample between a pair of filter paper sheets in the ambient air at a temperature of 30° C. at a humidity of 90% RH within 60 seconds after pulling up the test sample, and leaving the test sample under a pressure of 490 N/cm2 (50 kgf/m2) for 1 minute to lightly remove water in the test sample.
For clothes having a rate of change in air permeability of less than 30%, the air permeability of the clothes become insufficient when the wearer wears the clothes containing the water-wetted woven or knitted fabric and sweats. The clothes then cause the wearer to feel increased stuffiness or sultriness.
The woven or knitted fabric of the present invention contains the crimped composite filaments in a content of 10 to 100 mass %, and the content is preferably from 40 to 100 mass %. When the content is less than 10 mass %, the effect of the crimped composite filaments, namely, a reversible change between an increase and decrease in air permeability caused by wetting with water and drying of the woven or knitted fabric thus obtained becomes insufficient.
For the woven or knitted fabric of the present invention, the crimped composite filament is contained in yarns for forming the woven or knitted fabric. The percentage of crimp of the crimped composite filaments decreases upon wetting with water, whereby the apparent length of the yarn containing the crimped composite filament increases. As a result, the area of the woven or knitted fabric increases so as to increase the openings between yarns. Consequently, the air permeable opening area and the air permeability increase.
In order to enable the crimped composite filament-containing yarn to increase or decrease the apparent length thereof with a high efficiency, in response to a decrease or an increase of the crimping property of the crimped composite filaments and, thereby, the air permeability of the woven or knitted fabric to increase or decrease with high efficiency, the yarn is preferably a non-twisted or soft twisted one having a number of twists of 0 to 300 turns/m, particularly more preferably a non-twisted yarn. When the number of twists exceeds 300 turns/m, the resultant crimped composite filaments within the yarn mutually restrict the deformation thereof. Thus, a change in the percentage of crimp of the composite filaments, upon being wetted with water or drying, is also restrained and a change in the apparent length of the yarn is also restricted. Therefore, the change in the air permeability of the woven or knitted fabric may be also restricted.
In addition, a yarn containing the crimped composite filaments may be subjected to an air interlacing and/or false twist and crimping treatment. However, in this case, a number of interlacing among the filaments in the yarn is preferably from about 20 to 60/m.
The yarn containing crimped composite filaments optionally contains other type of filaments than the crimped composite filaments. The other filaments can be selected from non-crimped filaments and filaments having a difference in percentage of crimp DCF−HCF of less than 10%. There is no specific limitation to the type of a polymer for forming the other filaments. Examples of the polymer include polyesters, for example, poly(ethylene terephthalate), poly(trimethylene terephthalate) and poly(butylene terephthalate), polyamides, for example, nylon 6 and nylon 66, polyolefins, for example, polyethylene and polypropylene, acrylic polymers, p- or m-aramid polymers and modified polymers of the above mentioned polymers. Moreover, the other filaments may be selected from such filaments appropriate for clothes as natural fibers, regenerated fibers and semi-synthetic fibers. Among these filaments, filaments of polyester, for example, poly(ethylene terephthalate), poly(propylene terephthalate), poly(butylene terephthalate) or modified polyester in which the above copolymerization component is copolymerized are appropriate in view of the dimensional stability upon being wetted with water and the compatibility (filament-combinability, mixed knittability or mixed weavability and dyeability) with the composite filaments. Moreover, there are no specific restrictions to individual filament thickness of the other filaments and the number of individual filaments per yarn. However, in order to enhance the moisture absorption of the woven or knitted fabric and increase the air permeability of the fabric upon moisture-uptaking, the individual filament thickness is preferably from 0.1 to 5 dtex (more preferably 0.5 to 2 dtex), and the number of the individual filaments per yarn is preferably from 20 to 200 (more preferably from 30 to 100). In addition, other filaments may be air interlaced and/or conventionally false twisted and crimped so that the number of interlacing becomes about 20 to 60/m.
In the woven or knitted fabric of the present invention, the crimped composite filaments and the other filaments may respectively constitute at least one type of yarns, and these yarns may be mixed woven or knitted. Alternatively, the crimped composite filaments and the other yarn may constitute together a combined yarn, and air combining may be employed to form the combined yarn. Moreover, the crimped composite filaments yarn and the other filaments yarn may constitute together a doubled and twisted yarn or a doubled yarn, or they may also constitute a composite false twisted crimped yarn.
There is no restriction to the woven or knitted structures and the number of woven or knitted plies in the woven or knitted fabric of the present invention. The woven or knitted structures include, for example, weave structures such as plain weave, twill weave and satin weave, and a knitting stitch such as plain knitting, circular rib knitting, a tuck float knitting, plating stitch, a dembigh stitch and a half tricot stitch. Moreover, the above woven or knitted structures may each include a single ply structure and a multi-ply structure having two or more plies.
For the woven or knitted fabric of the present invention, in order to ensure the movability and deformability (crimp-changeability) of the crimped composite filaments in the woven or knitted fabric, the crimped composite filaments preferably have stretchability in the warp direction and/or weft direction. The stretchability is preferably 10% or more (more preferably 20% or more, still more preferably from 25 to 150%).
Next, for the woven or knitted fabric of the present invention, the composite filaments contained in the woven or knitted fabric of the invention have a crimped structure formed by manifesting their latent crimpability. It is important that the composite filaments satisfy the requirement represented by the following expression:
DC
F
−HC
F≧10 (%) (preferably 50 (%)≧DCF−HCF≧10
wherein DCF (%) is a percentage of crimp of the composite filaments upon drying, and HCF (%) is a percentage of crimp of the composite filaments upon being wetted with water. When DCF−HCF is less than 10%, the air permeability of the resultant fabric upon being wetted with water might not efficiently increase, unpreferably, in comparison with that upon drying.
The percentage crimp of a crimped composite filament in the woven or knitted fabric herein is determined by the following procedure. First, a woven or knitted fabric is left to stand in an atmosphere at 20° C. and 65% RH for 24 hours. Small samples (n=5) each having dimensions of 30 cm×30 cm are cut out from the conditioned woven or knitted fabric in the same direction thereof. Composite filaments are taken out from each small sample. A load of 1.76 mN/dtex (200 mg de) is applied to the composite filament sample, and the filament length L0f is determined. One minute after removal of the load, a load of 0.0176 mN/dtex (2 mg/de) is applied to the filament, and the filament length L1f is determined. Moreover, the composite filament sample is immersed in water at 30° C. for 2 hours, and then taken out. The sample is held between a pair of filter paper sheets within 60 sec after taking out, in the ambient air atmosphere at 30° C. and 90% RH, and then a pressure of 0.69 mN/cm2 is applied to the sample for 5 sec to lightly wipe out water. A load of 1.76 mN/dtex (200 mg de) is applied to the sample, and the filament length L0f′ is determined. One minute after removal of the load, a load of 0.0176 mN/dtex (2 mg/de) is applied to the sample, and the filament length L1f′ is determined. The percentage of crimp DCF (%) upon drying and the percentage of crimp HCF (%) upon being wetted with water are calculated from the following formula.
Percentage of crimp DCF (%) upon drying=((L0f−L1f)/L0f)×100
The difference (DCF−HCF) (%) is calculated from the above DCF and HCF values. In addition, n is then 5, and the average values are calculated.
The woven or knitted fabric of the invention may be subjected to water absorption treatment. When the woven or knitted fabric is subjected thereto, the air permeability of the fabric is likely to be improved even with a small amount of sweat. A conventional water absorption treatment is satisfactory for such a treatment. The following procedure is exemplified as a preferred water absorption treatment: a water absorption treatment agent such as a poly(ethylene glycol diacrylate) or its derivative, or a poly(ethylene terephthalate)-poly(ethylene glycol) copolymer is allowed to adhere in an amount of 0.25 to 0.50% by weight based on the weight of the woven or knitted fabric to the woven or knitted fabric. Examples of the water absorption treatment method include a bath treatment method in which a water absorption treatment agent is added to a dyeing solution during dyeing, and a dipping method in which a woven or knitted fabric is dipped in a water absorption treatment solution and squeezed with a mangle before a dry-heat final set, a gravure coating method and screen printing method.
Furthermore, the woven or knitted fabric of the present invention may be subjected to a water-repellent treatment. The water-repellent treatment may be a conventional one. For example, such a method as described in Japanese Patent Publication No. 3133227 and Japanese Examined Patent Publication (Kokoku) No. 4-5786 is appropriate. That is, the method comprises mixing a commercially available fluororesin water repellant (e.g., trade name of Asahi Guard LS 317, manufactured by Asahi Glass Co., Ltd.) used as a water repellant with a melamine resin (optional component) and a catalyst to form a treatment agent containing about 3 to 15% by weight of the water repellant, and treating the surface of the woven or knitted fabric with the treatment agent at a pickup ratio of about 50 to 90%. Examples of the method of treating the surface of the woven or knitted fabric with the treatment agent include a padding method and a spraying method. Of these methods, the padding method is most preferred because the treatment agent penetrates into the interior of the woven or knitted fabric.
In addition, the pickup ratio is a proportion (%) of a weight of the treatment agent to a weight of the woven or knitted fabric (prior to imparting the treatment agent).
When the water repellency of the woven or knitted fabric after a water repellent treatment is evaluated in accordance with JIS L1092 6.2 (Spray Test), it is preferably evaluated to point 4 or more, more preferably point 5 (highest point).
For the water-repellent woven or knitted fabric thus obtained, because the percentage of crimp of the composite filaments contained in the woven or knitted fabric is efficiently decreases upon wetting with water, the yarn length of the composite filaments increases. As a result, openings in the woven or knitted fabrics are made large to improve the air permeability of the fabric. On the other hand, because the percentage of crimp ratio of the composite filaments increases upon drying, and a yarn length of the composite filaments is decreased. As a result, the openings in the woven or knitted fabric are made small to decrease the air permeability of the fabric.
The woven or knitted fabric of the present invention may be dyed. The conditions of dyeing will be explained in detail.
The woven or knitted fabric in the present invention includes the following embodiments: (1) a woven or knitted fabric having a multiply structure with at least two plies, and at least one ply containing the crimped composite filaments in an amount of 30 wt. % or more based on the total weight of the filaments from which the ply is formed; (2) a knitted fabric having a tubular knitting structure in which the loops of the tubular stitch are formed from yarns containing the composite filaments and the other filaments; (3) a woven fabric formed from warp yarns and/or a weft yarns of the weave structure, in which yarns the composite filaments and the other filaments are combined in parallel with each other; (4) a woven or knitted fabric wherein the composite filaments yarns and the other filaments yarns are used as constituent yarns, and alternately arranged with every one yarn or every a plurality of yarns (5) a woven or knitted fabric containing the composite filaments and the other filaments as a core-in-sheath type composite yarn in which the composite filaments are situated in the core portion and the other filaments are situated in the sheath portion.
Moreover, for a woven or knitted fabric containing the composite filaments and other filaments, when a filament length A of the composite filaments and a filament length B of the other filaments are in the relationship i A<B upon drying, the air permeability of the fabric preferably increases upon being wetted with water. Conversely, when A>B or A=B, the air permeability of the fabric may not increase upon being wetted with water, for the following reasons: when the percentage of crimp of the composite filaments decreases and the composite filaments are elongated by being wetted with water, the other filaments have no allowance for the elongation and cannot be adapted to the elongation of the composite filaments; as a result, the percentage of openings in the woven or knitted fabric decreases.
Herein, the filament length is determined by the following measurement. First, a woven or knitted fabric is left to stand in an atmosphere at 20° C. and 65% RH for 24 hours. Small samples (n=5) each having dimensions of 30 cm×30 cm are cut out from the conditioned woven or knitted fabric. One composite filament yarn and another different filament yarn are taken out of each sample. A filament length A (mm) of the composite filaments yarn and a filament length B (mm) of the other different filaments yarn are determined. During the determination, a load of 1.76 mN/dtex (200 mg/de) is applied to the sample filament yarn when the yarn is non-elastic, and a load of 0.0088 mN/dtex (1 mg/de) is applied to the sample filament yarn when the yarn is elastic. Herein, the composite filaments yarn and the other different filaments yarn must be taken out of the small sample in the same direction. For example, when the composite filaments yarn is taken out of the warp yarns (or weft yarns) of the woven or knitted fabric, the other different filaments yarn must also be taken out of the warp yarns (or weft yarns). Moreover, when composite yarns are formed from the composite filaments yarn and the other different filaments yarn, and the woven or knitted fabric is formed from the composite yarns, the composite yarns are taken out of the cut small sample (30 cm×30 cm) (n=5), and the composite filaments yarn and the other different filaments yarn are further taken out of the composite yarn. Measurements are similarly made on the taken-out yarns.
As explained above, in order to make a difference between a length A of the composite filaments yarn and a length B of the other different filaments yarn, the following methods are exemplified: when the woven or knitted fabric is woven or knitted from the composite filaments yarn and the other different filaments yarn, a method comprising adjusting the shrinkage of the other different filaments yarn in boiling water to 15% or less (more preferably 10% or less); and a method in which during conjugating the composite filaments yarn with the other different filaments yarn, the other different filaments yarn is overfed to the conjugating procedure.
In order to ensure the movability of composite filaments in the woven or knitted fabric of the present invention, the basis mass of the fabric is preferably adjusted to 300 g/m2 or less (more preferably 100 to 250 g/m2).
The woven or knitted fabric of the present invention can be easily produced by, for example, the following process.
A modified polyester having an intrinsic viscosity of 0.30 to 0.43 (determined at 35° C. with o-chlorophenol used as a solvent), in which 5-sodium sulfoisophthalic acid is copolymerized in an amount of 2.0 to 4.5 mol %, and a polyamide having an intrinsic viscosity of 1.0 to 1.4 (determined at 30° C. with m-cresol used as a solvent) are melt-spun together through a spinneret for a side-by-side or eccentric core-sheath composite filaments. It is particularly important that the intrinsic viscosity of the polyester resin component be 0.43 or less. When the intrinsic viscosity of the polyester resin component is higher than 0.43, the viscosity of the polyester component increases, and thus the physical properties of the resultant composite filaments become close to those of the yarns formed from only the polyester yarns, and thus the desired woven or knitted fabric in the present invention cannot be obtained unpreferably. Conversely, when the intrinsic viscosity of the polyester resin component is less than 0.30, the melt viscosity of the resin becomes too low and thus the spinnability of the resin decreases and fluff formation takes place often. As a result, the quality and the productivity might decrease.
A spinneret as disclosed in, for example, FIG. 1 in Japanese Unexamined Patent Publication (Kokai) No. 2000-144518, wherein the extrusion holes of the high viscosity side are separated from those of the low viscosity side, and the extrusion linear speed of the high viscosity side is lowered (cross-sectional area of the extrusion holes being increased). Moreover, a molten polyester is preferably passed through the high viscosity side extrusion holes, and a molten polyamide is preferably passed through the low viscosity side extrusion holes and extruded melt flows are cooled and solidified. The weight ratio of the polyester component to the polyamide component is, as explained above, preferably from 30:70 to 70:30 (more preferably from 40:60 to 60:40).
Furthermore, a separate drawing system wherein melt composite spinning is conducted, the spun yarn is wound once, and the wound yarn is drawn, may be adopted. A direct drawing system wherein the spun yarn is drawn and heat treated without winding may also be adopted. A conventional spinning and drawing conditions may be adopted for the process. For example, when a direct drawing system is conducted, a yarn is spun at a speed of about 1,000 to 3,500 m/min, and the spun yarn is successively drawn and wound at temperatures of 100 to 150° C. The draw ratio is suitably selected so that the composite filaments finally obtained exhibit an elongation at break of 10 to 60% (preferably 20 to 45%) and a tensile strength at break of about 3.0 to 4.7 cN/dtex.
Herein, the composite filaments preferably satisfy the requirements (1) and (2), simultaneously.
(1) The percentage of crimp DC of the composite filaments upon drying is from 1.5 to 13% (preferably from 2 to 6%).
(2) A difference (DC−HC) between the percentage of crimp DC upon drying and the percentage of crimp HC upon wetting with water of composite filaments is 0.5% or more (preferably 1 to 5%).
The term “upon drying” designates the state of a sample having been allowed to stand in an environment at a temperature of 20° C. at a humidity of 65% RH for 24 hours. On the other hand, the term “upon being wetted with water” designates the state of a sample that is immediately after immersing the sample in water at 30° C. for 2 hours. Numerical values obtained by the methods explained below will be used as the percentage of crimp DC upon drying and the percentage of crimp HC upon being wetted with water, respectively.
First, using a rewinding frame having a frame peripheral length of 1.125 m, a composite yarn is wound at a constant speed under a load of 49/50 mN×9×total tex (0.1 gf×total denier) applied to the yarn to form a small hank having a number of winding of 10 times. The small hank is twisted to form a double ring, and the twisted hank is treated in boiling water for 30 minutes under an initial load of 49/2,500 mN×20×9×total tex (2 mg×20×total denier) applied to the hank. After the boiling water treatment, the treated hank is dried in a drier at 100° C. for 30 minutes, and then further treated with a dry heat at 160° C. for 5 minutes while the initial load is kept applied. After dry heat treatment, the initial load is removed, and the hank is allowed to stand in an environment at 20° C. and 65% RH for 24 hours. The initial load and a heavy load of 98/50 mN×20×9×total tex (0.2 gf×20×total denier) are then applied to the hank, and the hank length L0 is determined. The heavy load alone is immediately removed, and the hank length L1 is determined at a stage of 1 minute after the load removal. Moreover, the hank is immersed in warm water at 20° C. for 2 hours while the initial load is kept applied. The hank is then taken out, and a pressure of 0.69 mN/cm2 (70 mgf/cm2) is applied to the hank with a filter paper sheet so that water is lightly wiped out. The initial load and the heavy load are then applied, and the hank length L0′ is determined. The heavy load alone is then immediately removed, and the hank length L1′ is determined at a stage of 1 minute after removal of the load. The percentage of crimp DC (%) upon drying, the percentage of crimp HC (%) upon being wetted with water and the difference (DC−HC) (%) between the percentage of crimp upon drying and that upon being wetted with water are calculated from the above determined numerical values using the following calculation expression:
Percentage of crimp DC (%) upon drying=((L0−L1)/L0)×100
Percentage of crimp HC (%) upon being wetted with water=((L0′−L1′)/L0′)×100
The percentage of crimp HC of the composite filaments during wetting with water is preferably in the range of from 0.5 to 10.0% (more preferably from 1 to 3%).
When the percentage of crimp DC of the composite filaments upon drying is less than 1.5%, a change in percentage of crimp upon being wetted with water decreases, and thus, a change in the air permeability of the woven or knitted fabric may decrease. Conversely, when the percentage of crimp DC of the woven or knitted fabric upon drying is greater than 13%, the crimp is hardly changed upon being wetted with water because the crimping is too strong, and thus an extent of change in the air permeability of the woven or knitted fabric may also decrease. Moreover, when a difference (DC−HC) between the percentage of crimp DC upon drying and the percentage of crimp HC upon being wetted with water of the woven or knitted fabric is less than 0.5%, an extent of a change in the air permeability of the woven or knitted fabric may also decrease.
Next, the woven or knitted fabric is prepared from the composite filaments alone or from the composite filaments and other filaments in combination, and the crimp of the composite filaments is manifested by heat treatment, for example, such a dyeing treatment.
Herein, it is important, as explained above, that in the production of a woven or knitted fabric, the composite filaments be woven or knitted in an amount of 10 wt. % or more (more preferably 40 wt. % or more), on the basis of the weight of the woven or knitted fabric. Moreover, there is no specific restriction to the woven or knitted structure, and it may be appropriately selected from the afore-mentioned structures.
The dyeing temperature is preferably from 100 to 140° C. (more preferably from 110 to 135° C.). The holding time at the highest temperature during dyeing procedure is preferably from 5 to 40 minutes. When the woven or knitted fabric is dyed under the above-mentioned conditions, a difference in thermal shrinkage between the polyester component and the polyamide component in the composite filaments manifests the crimps thereof. Selection of the above-mentioned polymers as the polyester component and the polyamide component enables the resultant composite filaments take a crimped structure during the manifestation of the crimp in which the polyamide component is located inside portions of the crimps.
After the dyeing is completed, the dyed woven or knitted fabric is usually subjected to a dry-heat final-set procedure. The dry-heat final-set temperature is preferably from 120 to 200° C. (more preferably from 140 to 180° C.), and the first heat-set time is preferably from 1 to 3 minutes. When the dry-heat final-set temperature is lower than 120° C., wrinkles generated during dyeing might remain. Moreover, the dimensional stability of finished articles may be insufficient. Conversely, when the dry heat final set temperature is higher than 200° C., the crimp of the composite filaments manifested during dyeing may be decreased, and the filaments may be hardened so as to cause the hand of the fabric to be stiff.
The woven or knitted fabric of the present invention may be subjected to various treatments, for example, conventional raising, UV-ray shielding or imparting functions with agents such as antibacterial agents, deodorants, moth-proofing agents, luminous agents, retroreflective agents, negative-ion-generating agents and water absorption agents.
The woven or knitted fabric of the present invention can be used for forming at least a part of the clothes, for example outerwear, sportswear and underwear by utilizing the characteristic that the percentage of crimp significantly decreases upon wetting with water the crimped composite filaments contained therein and consequently increasing the air permeability thereof.
The clothes of the present invention contain the woven or knitted fabric of the invention containing crimped composite filaments and having an air permeability that increases upon being wetted with water, and are characterized in that the dimensions of the clothes are reversibly enlarged upon being wetted with water to increase the air permeability and exhibit a ventilation effect.
The clothes of the present invention include outerwear, sportswear and underwear.
In a preferred embodiment of the clothes of the present invention, the clothes have a portion having no dimensional change when wetted with water, and a portion that reversibly increases the dimensions (reversibly increases the area) upon being wetted with water. In this embodiment, because the enlargement of the area caused upon being wetted with water is partially effected, neither the dimensions of the clothes as a whole nor the gap between the clothes and the skin of the wearer is excessively enlarged. That is, when a wearer puts the clothes of the above embodiment on and sweats, a portion having dimensions (area) increased upon being wetted with sweat bulges outside so that an air gap between the skin of the wearer and the portion increases to increase the air permeability of the wetted portion and the ventilation effect.
For the clothes of the present invention, a portion having no dimensional change upon being wetted with water designates a portion that has a change in area caused by water wetting of less than 5%, and a portion having a dimensional change when wetted with water designates a portion having a change in area caused upon being wetted with water of 5% or more. A change in area of a clothes portion is determined by the following method.
A woven or knitted fabric is allowed to stand in an environment at 20° C. and 65% RH (hereinafter referred to as during drying) for 24 hours, and a sample (square sample, 20 cm (warp)×20 cm (weft)) is cut out in the same direction as the woven or knitted fabric. The area (cm2) of the sample is defined as an area upon drying. On the other hand, the sample is immersed in water at 30° C. for 5 minutes (hereinafter referred to as upon being wetted with water), pulled up, and then held between 2 filter paper sheets within 60 sec after pulling up. A pressure of 490 N/m2 (50 kgf/m2) is applied for 1 minute to remove a water component present among filaments. The area (cm2) of the wetted sample is then determined. When the area is reduced by water wetting the sample, the case is also included in the case in which “the sample has no dimensional change upon being wetted with water.”
change in area (%)=((area during water wetting)−(area during drying))/(area during drying)×100
There is no specific restriction to the type of the embodiments of the clothes in the present invention. Examples of the woven or knitted fabric forming a portion that has no dimensional change upon being wetted with water include organic natural fibers, for example, cotton, wool and hemp fibers, organic synthetic fibers, for example, polyester fibers, nylon fibers and polyolefin fibers, organic semi-synthetic fibers, for example, cellulose acetate fibers and organic regenerated fibers, for example, viscose rayon fibers.
Among the fibers, polyester fibers are appropriate in view of the fiber strength and handleability. The polyester fibers are produced from a dicarboxylic acid component and a diglycol component. It is preferred to mainly use terephthalic acid as the dicarboxylic acid component. It is preferred to mainly use, as the diglycol component, at least one alkylene glycol selected from ethylene glycol, trimethylene glycol and tetramethylene glycol. Moreover, the polyester may be made to contain a third component in addition to the dicarboxylic acid component and the glycol component. Examples of the third component include a cationic dye-dyeable anionic component, for example, sodiosulfoisophthalic acid, a dicarboxylic acid other than terephthalic acid, for example, isophthalic acid, naphthalenedicarboxylic acid, adipic acid, and sebacic acid, and a glycol compound other than an alkylene glycol such as diethylene glycol, poly(ethylene glycol), bisphenol A and bisphenolsulfone. At least one of these compounds may be used.
Filaments having no dimensional change upon being wetted with water may optionally contain at least one of the following agents or materials: delustering agents (titanium dioxide), micropore-forming agents (metal salt of organic sulfonic acid), anti-coloring agents, thermal stabilizers, flame retardants (diantimony trioxide), fluorescent brighteners, coloring pigments, antistatic agents (metal salt of a sulfonic acid), a hygroscopic agents (poly(oxyalkylene glycol)), antibacterial agents and other inorganic particles.
There is no specific restriction to the shape of filaments having no dimensional change upon being wetted with water. It may be either filaments (multifilaments) or a staple fiber. In view of obtaining a high flexibility, multifilaments are preferred. Moreover, the filaments may be ones false twisted and crimped, twisted or air interlaced. There is no specific limitation to the thickness of the filaments. However, in view of obtaining a high flexibility, the filaments preferably have an individual filament thickness of 0.1 to 3 dtex, a number of filaments of 20 to 150 and a total thickness of 30 to 300 dtex. There is no specific restriction to the cross-sectional profile of the individual filament and the filament may have a triangular, flat, cross, hexagonal or hollow cross-sectional shape, in addition to a regular circular cross-sectional shape.
There is no specific restriction to the structure of the woven or knitted fabric that has no dimensional change even when wetted with water, and conventional ones may be used. Examples of the weave structure of the woven fabric include three foundation weaves, namely plain weave, twill weave and satin weave, derivative weaves, for example, derivative twill weave, one side double structures, for example, warp double weave and weft double weave, and warp velvet weave. The type of the knitted fabric may be a weft knitted fabric or a warp knitted fabric. Preferred examples of the weft knitted stitch include a plain stitch, a rubber stitch, a double face stitch, a purl stitch, a tuck stitch, a float stitch, a half cardigan rib stitch, a lace stitch and a plating stitch. Examples of the warp knitting stitch include a single dembigh stitch, a single atlas stitch, a double cord stitch, a half tricot stitch, a fleecy stitch and a jacquard stitch.
In the above embodiments of the clothes of the present invention, portions, the dimensions of which are reversibly enlarged upon wetting with water, are locally arranged, and the other portions are formed from a woven or knitted fabric the dimensions of which are not changed even upon wetting with water. Sites where the wearer sweats relatively much are appropriate as the portions the dimensions of which are reversibly enlarged upon wetting with water. Examples of the appropriate portions are as follows: woven or knitted fabric portions 6 arranged in a front 5 schematically shown in
The woven or knitted fabric of the present invention is used as a fabric for forming a portion of the clothes the dimensions of which are reversibly enlarged upon being wetted with water.
There are no specific restrictions to the woven or knitted fabric structure and a number of plies of the woven or knitted fabric the dimensions of which are reversibly enlarged by wetting with water, for the clothes. The following are appropriately exemplified as the woven or knitted fabric: woven structures, for example, plain weave, twill weave and satin, and knitting stitch, for example, plain knitting stitch, an interlock stitch, a circular rib fabric, a tuck float fabric, a plating stitch, a dembigh stitch and a half tricot stitch. A tubular knitted or a mesh-like woven or knitted fabric is particularly preferred.
For a change in dimensions of the above-mentioned portions, the change in the area is preferably 10% or more, more preferably from 15 to 30%. When the change in the area is less than 10%, a space volume between the clothes and the skin upon wetting with water does not increase so much, and the ventilation effect may be insufficient. The woven or knitted fabric for forming the portions having a dimensional change upon wetting with water can be easily obtained by, for example, the production process explained above.
The woven or knitted fabric for clothes of the present invention is preferably subjected to a water absorbent treatment. The water absorbent treatment enables the treated woven or knitted fabric to exhibit an increased air permeability even upon wetting with a small amount of sweat. There is no specific limitation to the type of the water absorbent treatment. The following procedure is exemplified as a preferred water absorbent treatment: a water absorbent treatment agent, for example, a poly(ethylene glycol diacrylate) or its derivative, or a poly(ethylene terephthalate)-poly(ethylene glycol) copolymer is applied to the woven or knitted fabric, in an amount of 0.25 to 0.50 wt. % based on the weight of the woven or knitted fabric. Examples of the water absorbent treatment method include a bath treatment method in which a water absorbent treatment agent is added to a dyeing solution during dyeing, and a coating method in which, for example, a woven or knitted fabric is dipped prior to dry heat final set in a water absorbent treatment solution, and squeezed with a mangle, a gravure coating method and a screen printing method.
The clothes of the present invention are prepared from the above woven or knitted fabric having no dimensional change upon wetting with water and the above-mentioned woven or knitted fabric the dimensions of which are reversibly enlarged upon wetting with water, by a conventional process. The woven or knitted fabrics of the present invention may be subjected to various treatments, for example, dyeing, water absorbent treatment, conventional raising, UV-ray shielding treatment or function-imparting treatment with, for example, antibacterial agents, deodorants, moth-proofing agents, luminous agents, retroreflective agents, negative-ion generating agents and water repellants.
When a wearer puts the clothes of present invention on, and sweats, portions of the clothes the dimensions of which are reversibly enlarged upon wetting with water are enlarged, and the portions flutter during wearer's movement to produce a ventilation effect (bellows effect) to cause the wearer to be released from a stuffy feeling and the stickiness created by the sweating. Excellent wearable comfortability can thus be obtained. The performance of the clothes of the present invention will be further explained in Example 4 and Comparative Example 3 to be explained later by making reference to
The clothes of the present invention can be appropriately used as outerwear, sportswear, underwear, etc. In addition, accessories such as buttons may be safely attached to the clothes of the invention.
The woven or knitted fabric and clothes of the present invention will be further explained by with reference to the following examples.
In examples and comparative examples, the following tests were conducted.
o-Chlorophenol was used as a solvent, and measurements were made at 35° C.
m-Cresol was used as a solvent, and measurements were carried out at a temperature of 30° C.
A filament sample was left to stand in a thermohygrostat chamber at an atmospheric temperature of 25° C. at a humidity of 60% RH for one day and night. The sample was then set in a Tensilon™ tensile tester (manufactured by Shimadzu Corporation) with a sample length of 100 mm, and stretched at a rate of 200 mm/min, and the tensile strength (cN/dtex) and the elongation (%) at break were determined. In addition, n was 5 and the average values were obtained.
The shrinkage in boiling water (hot water shrinkage) (%) was determined by the method specified in JIS L 1013-1998 17-15. In addition, n was 3, and the average value was obtained.
Using a rewinding frame having a frame peripheral length of 1.125 m, a composite yarn was rewound at a constant speed while a load of 49/50 mN×9×total tex (0.1 gf×total denier) was applied to the yarn, to form a small hank having wound 10 times. The small hank was twisted to form a double ring, and the twisted hank was treated in boiling water for 30 minutes while an initial load of 49/2,500 mN×20×9×total tex (2 mg×20×total denier) was applied. The hank treated in boiling water was dried with a drier at a temperature of 100° C. for 30 minutes, and then further treated with a dry heat at 160° C. for 5 minutes while the initial load was applied thereto. After dry heat treatment was completed, the initial load was removed, and the hank was left to stand in an environment at 20° C. and 65% RH for 24 hours. The initial load and a heavy load of 98/50 mN×20×9×total tex (0.2 gf×20×total denier) were then applied to the hank, and the length L0 of the hank was measured. The heavy load alone was immediately removed, and 1 minute after the load removal, the length L1 of the hank was measured. Moreover, the hank was immersed in warm water at a temperature of 30° C. for 2 hours while the initial load was applied thereto. The hank was then taken out, and within 60 sec after taking out the hank, the hank was lightly wiped with a filter paper sheet, while applying a pressure of 0.69 mN/cm2 (70 mgf/cm2) to the hank with a filter paper sheet, 30 cm×30 cm. The initial load and the heavy load were then applied, and the length L0′ of the hank was measured. The heavy load alone was then immediately removed, and 1 minute after removal of the load the length L1′ of the hank was measured. The percentage of crimp DC (%) of the filament sample upon drying, the percentage of crimp HC (%) of the sample upon wetting with water and the difference (DC−HC) (%) between the percentage of crimp upon drying and that upon wetting with water were calculated from the data of the above mentioned measurements in accordance with the following equations.
Percentage of crimp DC (%) upon drying=((L0−L1)/L0)×100
Percentage of crimp HC (%) upon wetting with water=((L0′'L1′)×100
Percentage of crimp HC (%) upon wetting with water=((L0′−L1′)/L0′)×100
In addition, n is 5, and the average values are obtained.
A woven or knitted fabric was left to stand in an air atmosphere at a temperature of 20° C. at a humidity of 65% RH for 24 hours. Small samples each having dimensions of 30 cm×30 cm were taken (n=5) from the woven or knitted fabric in the same direction thereof. A composite filament was taken out from each small sample. A load of 1.76 mN/dtex (200 mg de) was applied to the composite filament, and the length L2 of the filament was measured. One minute after removal of the load, a load of 0.0176 mN/dtex (2 mg/de) was applied to the filament, and the length L3 of the filament was measured. Moreover, the filament was immersed in water at a temperature of 30° C. for 2 hours, and then taken out. Within 60 sec after taking out, the sample was held between filter paper sheets, each in dimensions of 30 cm×30 cm, and a pressure of 0.69 mN/cm2 (70 mgf/cm2) was applied thereto for 5 sec to lightly wipe out water. A load of 1.76 mN/dtex (200 mg de) was applied to the sample, and the length L2′ of the filament was measured. One minute after removal of the load, a load of 0.0176 mN/dtex (2 mg/de) was applied to the sample, and the length L3′ of the filament was measured. The percentage of crimp DCF (%) upon drying, the percentage of crimp HCF (%) upon being wetted with water and the difference (DCF−HCF) (%) between the percentage of crimp upon drying and that upon being wetted with water were calculated from the data measured as mentioned above in accordance with the following equations. In addition, n was 5, and the average values were obtained.
Percentage of crimp DCF (%) upon drying=((L0f−L1f)/L1f)×100
Percentage of crimp HCF (%) upon wetting with water=((L0f′−L1f′)/L1f′)×100
The air permeability (ml/cm2/sec) of a fabric sample upon drying and the air permeability (ml/cm2/sec) upon being wetted with water were measured in accordance with JIS L 1096-1998 6.27.1, Method A (Fragile-type testing machine method). The term “upon drying” designated the state of a sample left to stand in an environment at a temperature of 20° C. at a humidity of 65% RH for 24 hours. On the other hand, the term “upon being wetted with water” designated the state of a sample that was subjected to the following procedures: the sample was immersed in water at a temperature of 30° C. for 2 hours, pulled up from the water, and within 60 sec after pulling up the sample, held between a pair of filter paper sheets each having dimensions of 50 cm×50 cm, while a pressure of 490 N/m2 (50 kgf/m2) was being applied to the sample for 1 minute to remove the water present among the filaments. The air permeability is then determined (n=5), and the average values are obtained. The change in air permeability is calculated from the following equation:
Change (%) of air permeability=((air permeability upon wetting with water)−(air permeability upon drying))/(air permeability upon drying)×100
The stretch elongation (%) in the warp direction and that in the weft direction of a woven or knitted fabric were determined by the same method as JIS L1096 8.14.1, Method B (Constant Load Method) except that the load was changed to 1/10 (1.47 N=0.15 kgf).
The average of the measured data (n=5) was calculated.
First, a woven or knitted fabric is left to stand in an air atmosphere at 20° C. and 65% RH for 24 hours. Small samples (n=5) each having dimensions of 30 cm×30 cm are taken from the woven or knitted fabric. One composite filaments yarn and another filaments yarn were taken out from each sample. A yarn length A (mm) of the composite filaments yarn and a yarn length B (mm) of the different filaments yarn were measured. In the measurement, a load of 1.76 mN/dtex (200 mg/de) was applied to a sample yarn when the yarn is a non-elastic yarn, and a load of 0.0088 mN/dtex (1 mg/de) was applied to a sample yarn when the yarn is an elastic one. In addition, n was 5, and the average was calculated.
The water repellency of the woven or knitted fabric was determined in accordance with JIS L1092, 6.2 Spray Test.
A woven or knitted fabric is allowed to stand in an environment at a temperature of 20° C. at a humidity of 65% RH for 24 hours, and square samples (20 cm (warp)×20 cm (weft) were taken in the same direction as the woven or knitted fabric. The area (cm2) of each sample is defined as an area (cm2) upon drying. The sample was immersed in water at a temperature of 20° C. for 5 minutes (hereinafter referred to as upon being wetted with water), then held between a pair of filter paper sheets while applying a pressure of 490 N/m2 (50 kgf/m2) to the sample for 1 minute to remove water present among filaments. The area of the sample was determined and defined as an area of the sample (cm2) upon being wetted with water. A change (%) in dimensions was calculated from the following equation defining the change in area of the sample.
Change in area (%)=((area upon wetting with water)−(area upon drying))/(area upon drying)×100
A nylon 6 having an intrinsic viscosity [η] of 1.3 was melted at 270° C., and a modified poly(ethylene terephthalate) in which 2.6 mol % of 5-sodium sulfoisophthalic acid was copolymerized and that had an intrinsic viscosity [η] of 0.39 was melted at 290° C. Both molten polymers were extruded through a spinneret for side-by-side type composite filaments in an extrusion rate of 12.7 g/min for each polymer. The spinneret was one described in Japanese Unexamined Patent Publication (Kokai) No. 2000-144518. The spinning nozzle was formed from two arc-shaped slits A and B arranged substantially on one the same circumference at a spacing d. The area SA of the arc-shaped slit A, the slit width A1, the area SB of the arc-shaped slit B, the slit width B1 and the area SC surrounded by the inner peripheral faces of the arc-shaped slits A and B simultaneously satisfy the following requirements (1) to (4):
(1) B1<A1
(2) 1.1≦SA/SB≦1.8
(3) 0.4≦(SA+SB)/SC≦10.0
(4) d/A1≦3.0
The poly(ethylene terephthalate) was extruded through the slit A side, and the nylon 6 was extruded through the slit B side to form a side-by-side type undrawn composite filaments yarn having a cross-sectional profile as shown in
The drawn composite filaments yarn thus obtained had a tensile strength at break of 3.4 cN/dtex and an elongation at break of 40%. Moreover, when the composite filaments yarn was subjected to a treatment in boiling water to cause the filaments to crimp, the filaments yarn had a percentage of crimp DC upon drying of 3.3% and a percentage of crimp HC upon being wetted with water of 1.6%. Thus the difference (DC−HC) between the percentage of crimp DC upon drying and the percentage of crimp HC upon wetting with water was 1.7%.
Using a 28-gauge double tubular knitting machine, a tubular knitted fabric having an interlock stitch with a knitting density of 42 courses/2.54 cm and 35 wales/2.54 cm was prepared from non-twisted composite filaments yarns (no treatment with boiling water was applied and no crimp was manifested on the filaments) alone.
The tubular knitted fabric was dyed at a temperature of 130° C. for a peak temperature-keeping time of 15 minutes to manifest the latent crimpability of the composite filaments yarn. During dyeing, a water-absorbent agent (poly(ethylene terephthalate)-poly(ethylene glycol) copolymer) was added to the dyeing bath in an amount of 2 ml per liter of the dyeing solution. The water-absorbent agent was imparted to the knitted fabric by the bath treatment during dyeing. Then the tubular knitted fabric was dry heat final set at 160° C. for one minute.
The knitted fabric thus obtained had a basis weight of 214 g/m2, and had a stretch percentage of 70% in the warp direction, and a stretch percentage of 110% in the weft direction, an air permeability upon drying of 90 ml/cm2/sec, an air permeability upon being wetted with water of 370 ml/cm2/sec and a change in air permeability of 311%. The significant improvement of the air permeability upon wetting with water was confirmed with satisfactory. Moreover, composite filaments taken from the knitted fabric had a percentage of crimp DCF upon drying of 68% and a percentage of crimp HCF upon being wetted with water of 22%. That is, the difference (DCF−HCF) between the percentage of crimp upon drying and the one upon wetting with water was 46%.
The same composite filaments yarn as used in Example 1 and a conventional poly(ethylene terephthalate) multifilaments yarn (84 dtex/30 f) were used. Using 28-gauge double tubular knitting machine in the same manner as in Example 1, the composite filaments yarns and the poly(ethylene terephthalate) multifilaments yarns were alternately fed to the machine with every one yarn to form a tubular knitted fabric having an interlock stitch with a knitting density of 54 courses/2.54 cm and 34 wales/2.54 cm. The tubular knitted fabric was subjected to dyeing, water absorbent treatment and dry heat final set in the same manner as in Example 1.
The knitted fabric thus obtained had a basis weight of 206 g/m2, and exhibited a stretch percentage of 50% in the warp direction, a stretch percentage of 100% in the weft direction, an air permeability upon drying of 150 ml/cm2/sec, an air permeability upon being wetted with water of 280 ml/cm2/sec and a change in air permeability of 87%. The knitted fabric was satisfactory because the air permeability upon being wetted with water was greatly improved. Moreover, a composite filaments taken from the knitted fabric had a percentage of crimp DCF upon drying of 63% and a percentage of crimp HCF upon wetting with water of 20%. That is, the difference (DCF−HCF) between the percentage of crimp upon drying and that upon being wetted with water was 43%.
A nylon 6 having an intrinsic viscosity [η] of 1.3 and a modified poly(ethylene terephthalate) in which 2.6 mol % of 5-sodium sulfoisophthalic acid was copolymerized and that had an intrinsic viscosity of 0.48 were melted at 270° C. and 290° C., respectively, extruded through a spinneret for forming a side-by-side type composite filaments (explained in Example 1) in an extrusion rate of 12.7 g/min for each polymer to form a side-by-side type composite filaments having a cross-sectional profile as shown in
From the composite filaments yarns, a tubular knitted fabric was prepared in the same manner as in Example 1. The resultant tubular knitted fabric was subjected to dyeing, water absorbent treatment and dry final set in the same manner as in Example 1.
The knitted fabric thus obtained had a basis weight of 170 g/m2, and exhibited a stretch percentage of 52% in the warp direction, a stretch percentage of 102% in the weft direction, an air permeability upon drying of 230 ml/cm2/sec, an air permeability upon being wetted with water of 160 ml/cm2/sec and a change in air permeability of −30%. The knitted fabric was unsatisfactory because the air permeability upon being wetted with water was low. Moreover, a composite filament taken from the knitted fabric had a percentage of crimp DCF upon drying of 54% and a percentage of crimp HCF upon being wetted with water of 65%. That is, the difference (DCF−HCF) between the percentage of crimp upon drying and that upon being wetted with water was −11%.
The same side-by-side type composite filaments yarns as in Example 1 were produced. The composite filaments yarns were supplied to a conventional 28-gauge tricot knitting machine. The composite filaments yarns were fed to a back guide bar of the knitting machine at a full set. On the other hand, a conventional false twisted, crimped poly(ethylene terephthalate) multifilament yarns (33 dtex/36 fil.) having a percentage of crimp of 20% were simultaneously fed to a front guide bar of the tubular knitting machine at a full set to give a knitted fabric having a half tricot stitch (back: 10-12, front: 23-10) with an on-machine density of 80 courses/2.54 cm.
The knitted fabric was dyed at 130° C. for a peak temperature-keeping time of 15 minutes so that the latent crimpability of the composite filaments was manifested. The knitted fabric was then subjected to padding treatment with a fluororesin water repellent treatment liquid. The treated knitted fabric was then dried at a temperature of 100° C., and dry heat final set at a temperature of 160° C. for 1 minute.
The knitted fabric thus obtained had a basis weight of 220 g/m2, and had a stretch percentage of 13% in the warp direction, a stretch percentage of 30% in the weft direction, a water repellency of 5 points, an air permeability upon drying of 45 ml/cm2/sec, an air permeability upon being wetted with water of 64 ml/cm2/sec and a change in air permeability of 42%. The knitted fabric was satisfactory because the air permeability upon wetting with water was greatly enhanced. Moreover, composite filaments taken from the knitted fabric exhibited a percentage of crimp DCF upon drying of 64% and a percentage of crimp HCF upon being wetted with water of 32%. That is, the difference (DCF−HCF) between the percentage of crimp upon drying and that upon being wetted with water was 32%.
A side-by-side type composite filaments yarns were produced from a nylon 6 and a 5-sodium sulfoisophthalic acid-copolymerized poly(ethylene terephthalate) resin in the same manner as in Comparative Example 1.
Using the composite filaments yarns, a knitted fabric was prepared in the same manner as in Example 3. The knitted fabric was subjected to dyeing, water repellency treatment and dry final set.
The knitted fabric thus obtained had a basis weight of 210 g/m2, and exhibited a stretch percentage of 12% in the warp direction, a stretch percentage of 22% in the weft direction, a water repellency of 5 points, an air permeability upon drying of 54 ml/cm2/sec, an air permeability upon being wetted with water of 41 ml/cm2/sec and a change in air permeability of −24%. The knitted fabric was unsatisfactory because the air permeability upon being wetted with water was low. Moreover, composite filaments taken from the knitted fabric exhibited a percentage of crimp DCF upon drying of 56% and a percentage of crimp HCF upon being wetted with water of 62%. That is, the difference (DCF−HCF) between the percentage of crimp upon drying and that upon being wetted with water was −6% which was unsatisfactory
A nylon 6 having an intrinsic viscosity [η] of 1.3 and a modified poly(ethylene terephthalate) in which 2.6 mol % of 5-sodium sulfoisophthalic acid was copolymerized and that had an intrinsic viscosity of 0.39 were melted at 270° C. and 290° C., respectively, extruded through the same composite spinning spinneret as in Example 1, at an extrusion rate of 12.7 g/min for each polymer, to form a side-by-side type composite filaments yarn. The extruded yarn was cooled to be solidified, and a spinning oil was imparted thereto. The yarn was then drawn and heat-treated at a speed of 1,000 m/min, by preheating by a preheating roller at a temperature of 60° C., and drawn and heat treated between the preheating roller and a heating roller having a speed of 3,050 m/min a temperature of at 150° C. The resultant yarn was wound. A composite filament yarn of 84 dtex/24 fil was obtained. The drawn composite filament yarn thus obtained had a tensile strength of 3.4 cN/dtex and an elongation at break of 40%. When the composite filaments yarn was subjected to a treatment in boiling water and the percentage of crimp was measured, it was found that the percentage of crimp DC upon drying was 3.3% and the percentage of crimp HC upon being wetted with water was 1.6%. The difference (DC−HC) between the percentage of crimp upon drying DC and the percentage of crimp upon being wetted with water HC was therefore 1.7%.
The composite filaments yarn (that was not subjected to treatment in boiling water, and that had no crimps, and non-twisted) alone was used, to produce a tubular knitted fabric having a plain knitting stitch and a density of 65 courses/2.54 cm and 37 wales/2.54 cm, by using a 28-gauge double tubular knitting machine.
The tubular knitted fabric was dyed at 130° C. for a peak temperature-keeping time of 15 minutes to manifest the latent crimpability of the composite filaments yarn. The tubular knitted fabric was then subjected to dry heat final set at a temperature of 160° C. for 1 minute.
The knitted fabric thus obtained (knitted fabric having dimensions that were reversibly increased upon wetting with water) had a basis weight of 120 g/m2, a knitting density of 71 courses/2.54 cm and 61 wales/2.54 cm, and exhibited a dimensional change of 21% (7% in the warp direction and 13% in the weft direction).
Separately, using a 28-gauge double knitting machine, a tubular knitted fabric having an interlock stitch with a gray fabric density of 45 courses/2.54 cm and 41 wales/2.54 cm was prepared from a false twisted and crimped poly(ethylene terephthalate) yarn (56 dtex/72 fil.). The knitted fabric was similarly dried as above. The knitted fabric (that had no dimensional change caused by wetting with water) was then cut and sewn to give a shirt with a half-sleeve length.
Next, the breast (15 cm long and 20 cm wide) alone of the shirt was cut and removed, and a cut piece of the composite filaments yarn knitted fabric was sewn and fixed to the breast of the shirt as shown in
A panelist wore the shirt thus obtained, and a wearing test was conducted in a room adjusted to a temperature of 28° C. and a humidity of 50% RH according to the wearing step mentioned below, and the humidity within the clothes (space between the skin and the clothes) was determined. The results are shown by a curve A in
rest for 5 minutes (with wind at 1.5 m/sec)→running for 15 minutes (10 km/h)→rest for 10 minutes (without wind)→rest for 20 minutes (with wind at 1.5 m/sec)
A panelist wore the same shirt prepared from the false twisted and crimped poly(ethylene terephthalate) yarn (56 dtex/72 f) alone as in Example 1, and the same wearing test as in Example 4 was conducted. The results are shown by a curve B in
The woven or knitted fabric of the present invention containing crimped composite filaments and clothes of the present invention containing the woven or knitted fabric exhibit an air permeability that is increased upon wetting with water to promote drying of the woven or knitted fabric. Drying of the woven or knitted fabric causes the air permeability to decrease and to improve the warmth retention. The woven or knitted fabric is therefore useful for outerwear, sportswear, underwear and other clothes.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2004-283758 | Sep 1994 | JP | national |
| 2004-281494 | Sep 2004 | JP | national |
| 2005-019486 | Jan 2005 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP05/18238 | 9/27/2005 | WO | 00 | 3/26/2007 |
