JP2000054250A - Artificial leather having good repeated stretch recovering property and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an artificial leather excellent in elastic restoring force in repeated stretching and having repeated stretching performance excellent in durability. SOLUTION: A sheet-like material obtained by interposing an elastic woven fabric in which >=1/4 of weft driving numbers are constituted by covered elastic yarn obtained by combining polyurethane elastic fiber with non-elastic fiber into the interior of interlacing layer of ultrafine fiber having <=0.5 denier and three-dimensionally interlacing the above ultrafine fiber interlacing layer with the above elastic woven fabric is impregnated into an aqueous polyurethane emulsion in which inorganic salts are previously dissolved and mixed and further heated and dried to provide the objective artificial leather having enhanced dynamic repeated stretchability.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an artificial leather having good dynamic repetition of elasticity recovery and substantially free from slipping or sagging when used in women's and men's clothing, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, there has been proposed a method of imparting elasticity to artificial leather in order to provide a comfortable clothing material. For example, Japanese Patent Application Laid-Open No. 07-216687 discloses that a conjugate filament capable of expressing a three-dimensional crimp by heating, a conjugate filament having a crimp developing ability, is disposed in a core portion, and a split type and / or ultrafine fiber can be formed. After weaving the core-sheath type two-layer structure yarn in which the sea-island type composite fiber is arranged in the sheath portion for the warp group and / or the weft group, the crimp of the conjugate filament is developed, and the split type and / or the sea island There has been proposed a method for producing a suede-like woven fabric in which at least a part of a type composite fiber is made into a fine fiber.

[0003] Japanese Patent Publication No. 06-39747 discloses that after weaving a woven yarn or a crimped yarn woven fabric made of a polymer of two or more components having different heat shrinkages, a hot water relaxing treatment is performed, and the drying temperature is reduced. A latently shrinkable woven fabric set at a lower temperature than the dyeing temperature is obtained, and the latently shrinkable woven fabric is interlaced with the ultrafine fiber entangled body and subjected to liquid flow three-dimensional entanglement. There is disclosed a method for producing artificial leather which is dyed at a high temperature and put into a width to impart stretchability to a woven fabric.

[0004] Japanese Patent Publication No. 62-117884 discloses 2
A woven fabric using a non-twisted crimped yarn composed of a 50-150 denier latently crimpable nylon multifilament yarn or polyester multifilament yarn imparted with 0-150 entangles / m for at least one of a warp and a weft group A method is disclosed in which an artificial leather having elasticity is produced by interposing a yarn inside a cross-sectional layer of artificial leather and thermally shrinking the yarn in the process of manufacturing the artificial leather.

[0005] In addition, Japanese Patent Publication No. 03-60945 discloses a strongly twisted knitted woven fabric using a polyester or polyamide fiber having a twist number of 500 T / m to 4000 T / m as a warp or a weft. A composite fiber forming ultra-fine elastic fibers (thermoplastic polyurethane) of 1.0 denier or less is interposed between composite fibers forming ultra-fine inelastic fibers of 0.8 denier or less and a main length of 20 mm or more. After the entanglement treatment, the latent torque in the strongly twisted knitted fabric is clarified in hot water, and then the extraction is performed with an organic solvent. Methods for producing artificial leather have also been proposed.

As described above, a method for producing artificial leather utilizing the heat shrinkage of fibers is an effective method for achieving good stretchability, and many products based on such a production principle are commercially available. ing. However, with the recent rise in fashion awareness, stretch materials have taken root in the market,
As consumers have grown in their eyes, there has been a growing need for consumers to seek products that are less likely to lose their shape. For example,
In the case of women's outerwear, a beautiful silhouette appears at first, but as the number of times of wearing increases, it comes off at the knees, back, elbows, buttocks, etc. where the strength is easily applied to the fabric in daily movements,
There is a problem that sagging occurs and the silhouette gradually collapses.

Usually, in the case of artificial leather of a woven or knitted fabric directly using a crimp-forming conjugate filament or artificial leather using a latently shrinkable fiber woven or knitted fabric as a core layer of the artificial leather, both heat-shrinkable polyester fibers and heat-shrinkable polyester fibers are used. // Because modified polyester fiber with different heat shrinkage will be used, for example, when used in the area where the force is concentrated at one point, such as the lower part of the skirt buttocks, the stretch recovery property of the polyester fiber itself Because the artificial leather is small, the bulky structure of the heat-shrinkable portion gradually breaks down while the artificial leather is subjected to the repetitive force, and the heat-shrinkage portion comes off and sags at that portion. In the case of thin artificial leather, slipping or sagging is particularly likely to occur.

[0008] Attempts have been made to prevent the bulky structure due to thermal shrinkage from being repeatedly collapsed by elongation and to impart durability to the stretchability. For example, in an attempt to lower the set temperature of the latently shrinkable fabric, increase the heat shrinkage width of the fabric, give the bulky structure a degree of freedom, and prevent the force from gathering at one point, only the shrinkage width is large. The thickness of the fabric and the feeling of tightness in the fabric are increased, and the texture and drape property are likely to be inferior. In consideration of the texture generated on the surface, there is a limit in setting the width of the fabric to be thermally shrunk. In addition, the width of the woven fabric is inevitably reduced, so that it is impossible to develop a wide woven fabric.
As another method, there is a method using thick denier heat-shrinkable polyester fiber. However, since a thick denier yarn is used, the stiffness, stiffness, and tightness of the woven fabric are increased, which is not preferable.

In the above-mentioned conventional artificial leathers, since polyester fiber is used in any of the methods, since the fiber elongation recovery property is small, the problem of detachment and sagging that occurs during repeated elongation still remains. Elongation performance with a high level of durability has not been obtained. The method of impregnating a polyurethane resin in a DMF solution is as follows:
The MF causes the polyurethane fiber in the elastic fiber fabric to be damaged by a dissolving action. In order to minimize this dissolving effect, for example, the sheet is sufficiently saturated with water in advance and a solution of a polyurethane resin is applied only to the surface layer or the back surface, or a polymer such as polyvinyl alcohol is impregnated in advance, or oil repellency is applied. A method is always applied to avoid the contact between the DMF and the polyurethane fiber due to the masking action of the treatment. However, the desired masking effect of DMF was not obtained, and it was difficult to avoid damage and contamination of polyurethane fibers. In the impregnation treatment with a polyurethane resin solution, it is necessary to apply a large amount of resin of at least 25% by weight or more in order to form a filling structure accompanied by foaming. When the amount of the resin increases, the binder effect of the polyurethane resin inevitably increases, and the movement of the essential polyurethane fibers in the artificial leather structure during expansion and contraction is restricted. Therefore, if the amount of resin to be applied is reduced, a high-density filling structure cannot be formed, the texture becomes cloth-like, the abrasion resistance properties deteriorate, and the commercial value of artificial leather is likely to be impaired. If you increase the proportion of polyurethane fiber used or use thicker denier polyurethane fiber so that the movement of the polyurethane fiber is not restricted and the movement of the polyurethane fiber is not restricted without reducing the amount of resin used, the feeling of rubber becomes strong, the texture is impaired, and the cost is high. Is also not preferred.

[0010]

DISCLOSURE OF THE INVENTION The present invention overcomes the above-mentioned problems and provides an artificial leather having a highly durable elasticity which does not substantially come off or set when subjected to repeated elongation in the weft direction. It is intended to be provided industrially.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to provide a light emitting device comprising:
An ultra-fine fiber in the micro-fiber entangled layer is formed into an elastic woven fabric in which at least 1/4 of the number of wefts in which the denier or less micro-fiber entangled layer is interposed in the core is a composite elastic yarn of polyurethane fiber and inelastic fiber. And a three-dimensional confounding to form a fabric structure, and the fabric structure is filled with an aqueous polyurethane resin, which is achieved by artificial leather having dynamic repetition of elasticity recovery in the weft direction.

[0012] The artificial leather of the present invention is a composite laminated fabric structure comprising an ultrafine fiber entangled layer, an inelastic fiber yarn as a warp, and an elastic woven fabric using a polyurethane elastic fiber yarn coated at least 1/4 of the number of wefts. By filling with a water-based urethane resin emulsion, the elongation-recovery property and texture in the longitudinal direction, which is particularly desired for general outerwear, are maintained, and the high-level weft-direction dynamic cyclic stretch-recovery property is stabilized. Has achieved artificial leather.

In the artificial leather thus improved according to the present invention, an ultrafine fiber web of 0.5 denier or less is composed of a composite elastic yarn of a polyurethane fiber and an inelastic fiber at least 1/4 of the number of wefts. A water-based polyurethane obtained by laminating on both sides of an elastic fabric, forming a microfiber entangled body layer, and also forming a sheet obtained by entanglement and binding of a part of the microfiber with the elastic woven fabric, in which inorganic salts are dissolved and mixed. It can be prepared by a method comprising impregnating in an emulsion solution, heating and drying.

Hereinafter, embodiments of the present invention will be described in detail. The microfiber entangled layer constituting the front and back surfaces of the artificial leather according to the present invention is a three-dimensional entangled layer of a dry or wet web of short fibers mainly composed of microfiber having a single fiber fineness of 0.5 denier or less, and is formed in the inner layer. Part of the fiber forms a structure which is firmly and integrally connected to the elastic woven fabric containing the polyurethane fiber at the core part by an anchoring action by entanglement with the tissue. If the entangled fiber layer is formed of fibers thicker than a single fiber fineness of 0.5 denier, the rigidity of the fibers is high, and the nap of the surface is strong. In addition, the quality having a lighting effect or the like is impaired.

The ultrafine fibers are obtained, for example, by ultrafine fibers directly spun by ordinary wet, dry and melt spinning methods, and further by melt blow method, sea-island type fiber spinning method, polymer blend spinning method, split fiber method, split yarn method and the like. And the resulting ultrafine fibers. The cross-sectional shape of the ultrafine fiber is not particularly limited, and an arbitrary ultrafine fiber such as a round, triangular, flat, or multi-lobed cross section is used. Further, as the polymer forming the ultrafine fibers, polyethylene terephthalate, polybutylene terephthalate, polyester elastomer, polyester dye such as cationic dyeable polyethylene terephthalate,
Polyamides such as nylon 6, nylon 66, polyamide elastomers, polyurethanes, polyolefins,
Polymers such as polyacrylonitrile are preferred. When the original fiber forming the ultrafine fiber is a composite fiber, the core or the above-mentioned polymer is preferable as the island component, and the sheath or the sea component is a copolymer polyester, a copolymer polyamide, a polyvinyl alcohol, a polystyrene and the like. One or two or more derivatives can be used in combination.

The elastic woven fabric disposed at the core of the ultrafine fiber layer is a woven fabric using inelastic fibers as warps and at least a part of wefts using a polyurethane fiber composite yarn. When the inelastic yarn is mixed with the weft of the elastic woven fabric, the inelastic fiber yarn and the polyurethane fiber composite elastic yarn are uniformly dispersed and driven into the woven fabric, for example, by alternately wefting one by one. It is necessary to be in.

The warp of the elastic woven fabric has a total fineness of 50 to 20.
It is a multifilament of synthetic fiber of about 0 denier, and a multifilament of polyester fiber such as polyethylene terephthalate is preferably used. It is most preferable to use a polyether-based polyurethane fiber as the polyurethane fiber constituting the composite elastic yarn. Polyester-based polyurethane elastic fibers are inferior in alkali resistance, and therefore easily hydrolyze during reductive washing of artificial leather dyeing. In addition, the polyether polyester block copolymer-based polyurethane fiber has a lower elongation recovery property than the polyether-based elastic fiber.

Examples of the inelastic fibers constituting the composite elastic yarn include fibers made of polyester polymers such as polyethylene terephthalate, polybutylene terephthalate, polyester elastomer, and cationic dyeable polyethylene terephthalate. Alternatively, a fiber composed of a polymer of two or more components may be used. This product uses polyurethane fiber in place of polyester crimped yarn and temporary woven yarn that have been used for artificial leather fabrics in the past. Back force), and the durability of the repeated stretching performance can be increased.

The form of the composite yarn of the polyurethane fiber and the inelastic fiber may be a core spun yarn in which the inelastic fiber is wound around the core yarn of the polyurethane fiber in a sheath shape, or the inelastic fiber may be wound around the polyurethane fiber in a coil shape. Single covering yarn and double covering yarn
Examples include a twisted yarn obtained by combusting a polyurethane fiber and an inelastic fiber, and a tangled yarn obtained by entanglement of polyurethane elastic with an inelastic fiber by an air jet. Considering the availability of the composite yarn, the productivity of the composite yarn, the cost, etc., the use of a single covering yarn or a double covering yarn is preferred.

In the case of covering yarn, the fineness of the polyurethane fiber and the inelastic fiber is 10 to 10 denier per yarn.
100 preferably 15 to 80 denier, most preferably 20 to 60 denier and a total fineness of 20 to 200 denier, preferably 50 to 180 denier, most preferably 7
0-150 denier is good. When the monofilament of the polyurethane fiber used is thicker than 100 denier, the elongation recovery performance is improved, but the stiffness and tension of the obtained artificial leather are increased, which is not preferable. Conversely, if the thickness is less than 10 denier, the elongation recovery performance is low, and sufficient improvement in the elongation recovery performance cannot be obtained. On the other hand, when the total fineness of the inelastic fiber is smaller than 20 denier, when the artificial leather is used, a sufficient level of tear strength cannot be obtained. Conversely, when the denier exceeds 200 denier, the three-dimensional structure with the ultrafine fiber entangled layer on the front and back surfaces is not obtained. The liquid entanglement is difficult, the peel strength is reduced, the wear resistance is deteriorated, and the texture of the product is hard.

The elastic woven fabric may be woven in any woven structure such as plain weave, twill weave and satin weave, but plain woven fabric is preferable in consideration of the thickness of the woven fabric and production cost. The weaving density of the woven fabric in the greige state is as follows: warp 30 to 70 / 2.54 cm, preferably 40 to 60 / 2.54 cm, weft 40 to 75 / 2.54 cm, preferably 50 to 65/2. .54c
m. The weaving density of the finished fabric is 35 to 75 warp / 2.54 cm, preferably 45 to 65 warp / 2.54 c.
m, weft 45-85 / 2.54 cm, preferably 55
７５75 / 2.54 cm.

The finish density of the elastic fabric is 35 yarns /
When it is less than 2.54 cm, when handled as a woven fabric, it becomes easy to be wrinkled, the resulting artificial leather has low tensile and tear strength, and its commercial value is reduced. Conversely, the warp is 7
If it exceeds 5 / 2.54 cm, the opening area of the fabric becomes small due to the influence of the adjacent warp yarns, so that the entanglement between the front and back ultrafine fiber entangled bodies is weak, the unevenness is increased, and the smoothness of the surface is impaired. Product value is reduced. Conversely, if the weft exceeds 85 / 2.54 cm, the opening area of the woven fabric becomes small due to the influence of adjacent wefts, and the front and back microfiber entangled bodies are weakly entangled and have poor abrasion resistance properties.

The basis weight of the elastic fabric is 20 to 200 g / m ^2.
And most preferably 30 to 1
It is 50 g / m ² . When the basis weight is less than 20 g / m ² , the handling of the fabric becomes troublesome, the warp and the weft become liable to be twisted, and the lamination with the superfine fiber entangled body layers on the front and back surfaces becomes difficult and wrinkles are formed. Conversely, 200g /
If it exceeds m ² , three-dimensional liquid flow entanglement between the front and back surfaces and the ultrafine fiber entangled body layer will be hindered, and the peel strength will be reduced and the wear resistance will be degraded.

The weft of the elastic fabric used in the present invention includes:
As described above, a composite elastic yarn obtained by compounding a polyurethane fiber and an inelastic fiber and a polyester filament yarn can be used in combination. The total fineness of the polyester filament yarn is 50 to 200 denier, preferably 70 to
It is ~ 150 denier. If the total fineness of the polyester filament yarn is less than 50 denier, the feeling of falling of the texture becomes worse, and the fabric becomes very cloth-like. Conversely, if the total fineness exceeds 200 denier, the stiffness and tightness of the texture are increased, which is not preferable. As described above, when the weft yarns are mixed, for example, at least 1/4 or more of the number of the weft yarns (in this case, the polyester yarns are repeatedly driven in a state where there are three polyester filament yarns between the composite elastic yarns). ) Must be a woven fabric into which a composite elastic yarn in which a polyurethane fiber and an inelastic fiber are compounded. Preferably, a composite elastic yarn of a polyurethane fiber and an inelastic fiber is driven into at least １ ／ or more of the number of weft yarns (in this case, the composite elastic yarn and the polyester filament yarn are repeatedly driven in a state where they are alternately arranged). Woven fabric is used. Most preferably, all the wefts are composite elastic yarns.

The water-based polyurethane emulsion used in the present invention is a nonionic emulsion obtained by forcibly emulsifying with high mechanical shear force in water in the presence of an emulsifier, for example, a nonionic emulsifier. It has a diameter of 0.1 to 2.0 μm. If the average particle size of the emulsion particles is less than 0.1 μm, migration during drying cannot be suppressed, so that a product having good abrasion resistance cannot be obtained, and it is difficult to stably carry out the process industrially. Conversely, if it exceeds 2.0 μm,
The stability of the emulsion is also impaired, the film-forming properties of the resin are inferior, urethane drops off during dyeing, and the abrasion resistance is impaired.

The water-based polyurethane resin used in the present invention includes a polyether-based non-yellowing polyurethane resin,
Polycarbonate-based non-yellowing polyurethane resins are preferred from the viewpoints of heat resistance, hot water resistance, and light resistance, but are not particularly limited. Examples of the composition of the polyurethane constituting the aqueous polyurethane resin include, as polyol components, polyester diols such as polyethylene adipate glycol and polybutylene adipate glycol; polyether glycols such as polyethylene glycol and polytetramethylene glycol; and polycarbonate diols. Examples of the isocyanate component include aromatic diisocyanates such as diphenylmethane-4,4'-diisocyanate; and aliphatic diisocyanates such as dicyclohexylmethane-4,4'-diisocyanate. Examples of the chain extender include glycols such as ethylene glycol; and diamines such as ethylene diamine and 4,4'-diaminodiphenylmethane. The aqueous polyurethane emulsion is prepared by a conventional method by appropriately combining the above-exemplified polyol, isocyanate, and chain extender.

The water-based polyurethane resin applied in the present invention preferably has the following properties. (1) Nonionic emulsion forcedly emulsified and the average particle size of emulsion particles is 0.1 to 2.0 μm. (2) N, of a resin film formed by drying an aqueous polyurethane emulsion at 120 ° C. The dissolution rate in N-dimethylformamide should be 12% or less.
After the drying treatment, the adhesive strength between the resin film and the nonwoven fabric sheet (hereinafter, simply referred to as adhesive strength A) is 1.2 g / cm.
In the present invention, by using an aqueous polyurethane resin that satisfies the properties (1) to (3), it is possible to reduce the polyurethane detachment rate of the impregnated fabric by 130 ° C. liquid jet dyeing in terms of polyurethane resin.
It can be kept to 0% or less, and adhesion of the dropped polyurethane to the dyeing machine wall can be substantially prevented. At this time, the amount (solid content) of the polyurethane resin constituting the water-based polyurethane emulsion is arbitrarily selected depending on the purpose.

In the present invention, in order to prevent the elastic expansion and contraction action (stretching performance) of the polyurethane fiber constituting the artificial leather from being restrained in the leather, a very small amount of 3% is applied to the basis weight of the three-dimensional interlaced fabric structure. -20 parts by weight, preferably 3-1
5 parts by weight, most preferably 3 to 10 parts by weight. If the amount of the polyurethane resin is less than 3 parts by weight, the polyurethane resin does not effectively adhere to the entanglement point of the ultrafine fibers, so that the wear resistance is impaired. On the other hand, when it is 20 parts by weight or more,
It is not preferable because the movement of elastic stretching for the recovery of the essential polyurethane fiber is restricted.

The water-based polyurethane resin is as described in the above (1) to (4).
An aqueous polyurethane resin having the following properties (4) and (5) in addition to the property (3) is preferable. (4) After air-drying the aqueous polyurethane emulsion stock solution, 1
The exothermic peak of the exothermic peak generated by the differential scanning calorimeter (DCS) of the resin film obtained by treating at 30 ° C. up to 300 ° C. is 50 mj / mg or less, and the top temperature of the exothermic peak is 215. (5) a water-based polyurethane resin having an adhesive strength between a resin film and a stainless steel plate after drying the water-based polyurethane emulsion at 180 ° C (hereinafter abbreviated as adhesive strength B) of 700 g / cm or less. Being a polyurethane resin If an aqueous polyurethane resin having the properties (4) to (5) is used, it has better heat resistance than a normal aqueous polyurethane resin. Since the amount of falling off is small and it is difficult to adhere to the dyeing machine wall even if it falls off, and the dropped urethane does not easily adhere to the fabric, the operating rate of the liquid flow dyeing machine and the processing yield It can be increased. In addition, since the falling off of the polyurethane resin during dyeing can be suppressed, the required consumption performance can be imparted to the product with an extremely small amount (3 to 10 parts by weight) of the polyurethane resin. As a result, the restraint on the movement of the polyurethane fiber inside the artificial leather is reduced, so that the elastic stretching performance can be maximized during repeated elongation.

Such an aqueous polyurethane emulsion can be prepared by the following method. Using a hydrophobic polyol, a component for imparting hydrophilicity to enhance the dispersibility of an emulsion in water and a polyisocyanate as raw materials, a urethane prepolymer having a terminal isocyanate group is subjected to a known one-stage method or a multi-stage isocyanate polyaddition reaction method. If necessary, a low molecular chain extender having two or more active hydrogen atoms such as ethylene glycol, propylene glycol, trimethylol, 1,4-butanediol and the like is added, and the reaction temperature is increased. 4
A nonionic emulsifier is mixed with a solution of a urethane prepolymer having a terminal isocyanate group synthesized at 0 to 150 ° C. (for example, methyl ethyl ketone, toluene, and ethyl acetate), and the mixture is mixed with water using a homomixer or a homogenizer. It is prepared by a method of strongly dispersing and adding a polyamine compound having two or more primary and / or secondary amine groups in one molecule as a chain extender to extend the chain.

Examples of the hydrophobic polyol component are those having a hydroxyl group at the end and a molecular weight of 500 to 4,000, for example, polyethylene adipate, polyethylene propylene adipate, polybutylene adipate, polyethylene butylene adipate, polyethylene terephthalate adipate, polyethylene isoprophate. Polyester polyols such as phthalate adipate, polyhexamethylene isophthalate adipate, and other polyester polyols, and polyoxytetramethylene glycol, polyoxypropylene glycol, and the like can be given.

Examples of the compound providing a polyoxyethylene group incorporated for the purpose of imparting hydrophilicity in order to enhance the dispersibility of the water-based polyurethane emulsion in water include polyoxyethylene glycol having a molecular weight of 400 to 4000, polyoxyethylene glycol, and polyoxyethylene glycol. Oxyethylene propylene glycol and polyoxyethylene tetramethylene glycol are exemplified. The content of the polyoxyethylene group in the total polyol component used in the production of the urethane prepolymer is preferably 5 to 30% by weight.

As the polyisocyanate component, aromatic, aliphatic and alicyclic polyisocyanates can be used, and xylylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate,
Hexamethylene diisocyanate and the like can be mentioned. Examples of the polyamine compound include ethylenediamine, tetramethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, hydrazine, piperazine, diaminediphenylmethane, tolylenediamine, xylendiamine, and isophoronediamine.

Characteristics (1) of water-based polyurethane resin
Specific examples of commercially available water-based polyurethane emulsions satisfying (3) include a polyether-based urethane resin and Evaphanol AP-12 (manufactured by Nichika Chemical Co., Ltd.).
Solids content of 40% by weight) and Chimassorb 944 described below.
The resin properties of (4) and (5) are exhibited by using LD (an oxidizing agent manufactured by Ciba Geigy) in combination. Also,
Specific examples of commercially available water-based polyurethane emulsions that simultaneously satisfy the resin properties of (1) to (5) include the polycarbonate urethane resin Evaphanol APC-5.
5 (manufactured by Nichika Chemical Co., Ltd., solid content 35% by weight).

As described above, according to the present invention, the amount of the polyurethane resin used is reduced to about 1/3 (10
(% By weight or less), but it is possible to obtain a performance that can withstand practical use while reducing the constraint on the movement of the polyurethane fiber in the leather structure, and to maximize its expansion and contraction performance. it can. As described above, the reason why the above-described performance can be obtained with a small amount of resin is presumed to be that the adhesive resin film is formed such that the aqueous polyurethane resin is aggregated at the entanglement point with the fiber.

In the polyurethane resin emulsion, if necessary, a stabilizer such as an ultraviolet absorber, an antioxidant, a coloring agent such as a pigment, a surfactant such as a penetrant, a fungicide, a thickener, polyvinyl alcohol, CMC Water-soluble polymer compounds such as
It is also possible to add a heat-sensitive accelerator such as a polyvinyl methyl ether. In particular, it is effective to use an antioxidant in combination with a water-based polyurethane emulsion as a heat resistance improver. As an antioxidant, a hindered amine-based polymer grade exhibits a particularly excellent effect. For example, there is "Kimasorb 944LD" (manufactured by Ciba Geigy). The amount of the antioxidant added is in the range of 0.5 to 10% by weight, preferably 1 to 5% by weight, based on the solid content of the urethane resin. If the added amount of the antioxidant is less than 0.5% by weight, the effect of improving the heat resistance is insufficient, and if it exceeds 10% by weight, the heat resistance is not further improved, and on the other hand, the foaming occurs and the feeling is reduced. However, it is not preferable because the cost is increased.

As described above, the present invention relates to an ultrafine fiber entangled fabric structure in which at least one-fourth of the number of wefts is composed of a composite elastic yarn of a polyurethane fiber and a non-elastic fiber, and an impregnated and filled urethane. An artificial leather structure combining the use of an aqueous polyurethane resin as a resin enhances the weft stretch recovery of the artificial leather and improves its dynamic durability.

The improvement in weft elasticity recovery and dynamic durability of the artificial leather of the present invention is remarkable as described in Examples below. The artificial leather according to the present invention has a 20% weft elongation recovery rate of more than 85%, and the artificial leather having a 20% weft elongation recovery rate of 80% is generally considered to have excellent stretchability. It can be said that it has an extremely high level of stretch performance.

Next, the artificial leather of the present invention has a remarkable dynamic durability of weft stretching recovery represented by a dynamic bagging value measured by a dynamic bagging test apparatus capable of movement equivalent to the elbow of a human body described later. By solving the problem, the problem of slipping and sagging which is a problem in the secondary product of the outer garment made of artificial leather is solved. Here, the dynamic bagging test device is manufactured by the present applicant to simulate the bending motion of the elbow of the human body and measure and evaluate the area of the artificial leather caused by the bending of the elbow (10,000 times). Test equipment.

The artificial leather of the present invention is subjected to a test described below in accordance with the dynamic bagging test method, and the area (moving bagging B) after leaving for 24 hours is at a level of 3 which can be understood if attention is paid to missing.
0 cm ² or less, preferably 20 cm ² or less. In the artificial leather of the present invention, once it is left in a natural state, the part that has been repeatedly expanded and contracted exhibits a high durability elasticity in the weft direction that returns to the original state, and even when used as a women's or men's clothing material, It can be said that the fabric material is less likely to be distorted than conventional products and can retain the initial silhouette.

Hereinafter, the method for producing the artificial leather of the present invention will be described. Polyester multifilant yarn is used as warp, and polyurethane elastic fiber yarn is made of polyester fiber yarn with lower heat shrinkability than polyurethane fiber by single covering etc. The elastic fabric is woven by driving at a predetermined weaving density using a loom. Thereafter, the green fabric of the elastic fabric is passed through a dryer directly while being unwound, and is heat-set at a temperature and a tension within a range that does not reduce the elasticity of the polyurethane fiber. By this heat setting, the heat shrinkage of the polyester fiber in the covering elastic composite yarn is reduced, the heat shrinkage of the polyurethane fiber is also suppressed, and the heat shrinkage of the polyurethane composite elastic yarn is suppressed. It is possible to finish the elastic woven fabric whose generation is suppressed and whose shape is stable.

The elastic fabric greige shrinks immediately in the free tension state due to the large resilience of the polyurethane fibers forming the weft, causing the eyes to become unsightly. From the state of the wound form after weaving, it is important to send the cloth to the greige setting step while applying tension and spreading. The heat set is 140
Performed through a dryer at ~ 190 ° C for 10-20 seconds,
Thereafter, after performing hot water relaxation processing by a multi-stage relaxation method of two or three or more stages in which the temperature is changed from a low temperature to a temperature in the range of 40 to 100 ° C. for 1 to 5 minutes, 160 to 190 ° C. while spreading. It is preferable to prepare an elastic woven fabric prior to lamination with a microfiber web by employing a method of drying by passing through a dryer for 10 to 30 seconds. The tension applied to the elastic woven fabric in the above-mentioned drying setting step becomes unpinned at the time of drying, and becomes uneven due to the sweetness of the setting property of the polyurethane fiber, blindness, and unevenness in the width of the elastic woven fabric, and conversely, the setting is too strong. This causes problems such as loss of elasticity of the polyurethane fiber. In elastic fabrics, 1 /
When using an elastic woven fabric in which two or more are occupied by composite elastic yarn, the heat shrinkage during hot water relaxation processing becomes large, and the following steps become unstable. It is necessary to reduce

On both sides of the elastic woven fabric set as described above, a dry method such as a card, a cross layer, a random wiper, etc., using ultra-fine fibers of 0.5 denier or less,
Lamination is prepared by laminating webs from ultra-fine fibers of 0.5 denier or less prepared by wet papermaking or the like, and a liquid flow (water flow)
It is obtained integrally by performing a confounding process and performing three-dimensional confounding.

The liquid flow (water flow) entanglement treatment referred to here is to laminate the ultrafine fiber cloth on both sides of the above-mentioned elastic woven fabric,
It is to be placed on a 150-mesh mesh support and subjected to hydroentanglement of the front and back surfaces at least once or more. At that time, considering the basis weight of the elastic woven fabric and microfiber web in the laminate, select the nozzle diameter, interval, arrangement, nozzle swing width, swing speed, laminate running speed, treatment water pressure, etc. as appropriate. I just need. Usually, the diameter of the nozzle is selected to be about 0.08 to 0.8 mm, and the water pressure is selected to be 10 to 150 kg / cm ² . If the water pressure is 10 kg / cm ² or less, sufficient entanglement strength cannot be obtained between the ultrafine fiber web and the elastic woven fabric, and the abrasion resistance properties are deteriorated. Conversely, treatment at a high pressure of 150 kg / cm ² or more is not preferable because the entangled nozzle trajectory is deeply carved on the front and back surfaces, the surface irregularities are severe, and the product quality is significantly impaired. In the water entanglement of the present invention, when the ultrafine fiber web on the front and back surfaces and the elastic fabric are entangled with each other, without treatment with a high-pressure water flow such that the nozzle trace is remarkably conspicuous, for example, a small diameter nozzle having a nozzle diameter of 0.04 mm or less It is preferable to increase the water pressure sequentially from low pressure, and to water-flow the front and back surfaces a plurality of times to strengthen the entangled structure.

The three-dimensional confounding process is performed by the needle punch method.
That could damage the composite elastic thread with needle driving
Not preferred. Laminate webs by wet papermaking
Applying liquid entangling method to this to produce nonwoven sheet
Polyurethane composite bullets whose method causes deterioration of mechanical properties
This is preferable because the sex yarn is not damaged. In the present invention
Is an aqueous system having specific resin properties for the three-dimensional entangled body described above.
Artificial leather raw fabric given polyurethane resin by impregnation method
Is prepared. The water-based polyurethane resin used is strong
Obtained in the form of an emulsified nonionic emulsion, average
It is an emulsion having a particle size of 0.1 to 2.0 μm. This
Water-based polyurethane emulsion such as
To prevent migration during drying.
It is necessary to stop. In the present invention, migration
For prevention, select from alkali metals or alkaline earth metals.
Monovalent or divalent metal sulfates, nitrates, chlorides, etc.
Any inorganic salts, for example, NaCl, Na_TwoSO_Four, Na
NO_Three, CaSO _Four, CaCl_Two, MgCl_TwoAnd so on
Process management, availability of raw materials, economy, public
Comprehensively judging from the viewpoint of harm etc._TwoSO_FourIs preferred
New For example, beforehand in an aqueous polyurethane emulsion
Na_TwoSO_FourAre dissolved and mixed at a temperature of 60-80 ° C.
Water-based polyurethane emulsion causes thermal gel
Adjust, resin component prevents migration to surface layer
It is important to be creative. Water-based polyurethane
To obtain the effect of preventing marsion migration
The concentration of inorganic salts used depends on the type of salt.
Emulsion properties are different, so it is not possible to say
Is desirably 1 to 10% by weight based on the solid content. Water based poly
The urethane emulsion has a resin concentration of 2 even when heated.
If it is less than 0%, it does not coagulate by heat,
And heat-induced gelation when heated at a temperature below 80 ° C
Water-based polyurethane sheet
Can be uniformly applied to the inside. Large amounts of
The addition of inorganic salts may cause the emulsion to gel at room temperature.
And should be avoided.

The method of applying the aqueous polyurethane emulsion to which the inorganic salts are added to the entangled fabric structure of the ultrafine fibers and the elastic woven fabric can be carried out by applying any method such as an impregnation method, a spray method, a coating method and the like. The amount of the water-based polyurethane emulsion to be applied is 3 to 20 parts by weight, preferably 3 to 15 parts by weight, based on the basis weight of the three-dimensional entangled fabric structure.
Most preferably, it is 3 to 10 parts by weight. The solid content concentration of the aqueous polyurethane emulsion liquid to be in this range,
The pickup rate or the like may be adjusted. To reduce the impregnation spot, the solid concentration of the aqueous polyurethane emulsion should be 3 ~
Preferably it is 20% by weight. When the concentration is 20% by weight or more, the viscosity of the aqueous polyurethane emulsion may be too high to impregnate uniformly. vice versa,
If it is less than 3% by weight, the amount of water to be removed in the next drying treatment increases, resulting in inefficiency. Further, the aqueous polyurethane emulsion solution within the above-mentioned concentration range may be picked up so that the target amount of the aqueous polyurethane applied is achieved.
The amount of water to be removed during the next drying process increases, resulting in inefficiency. Usually, it is preferable to adjust the concentration of the aqueous polyurethane resin so that the pickup rate becomes 50 to 200%.

Drying after application is performed by hot air drying, infrared drying,
Although any heating means such as high-frequency heating can be appropriately applied, a hot air dryer such as a pin tenter or a clip tenter is generally used. The drying temperature must be equal to or higher than the gelation temperature of the water-based polyurethane emulsion imparted with heat sensitivity. This temperature is typically 60
It is preferable that the temperature be set to 80 ° C. In order to achieve the full performance of the gelled resin, the drying temperature should be at least 110.
C., and preferably 120 ° C. or higher. However, a drying temperature of 190 ° C. or higher should be avoided because it is necessary to consider thermal deterioration of the polyurethane fiber. For example, when using a pin tenter dryer having a plurality of drying chambers, a relatively low temperature (80 to 140 ° C.) is used in the first half of the dryer.
The water in the three-dimensional entangled fabric structure gradually impregnated with the water-based polyurethane emulsion is removed, and then the water-based polyurethane resin is heat-set in the latter half of the dryer to migrate the water-based polyurethane resin to the surface of the fabric structure. It is desirable to adopt a method of processing while suppressing and preventing.

[0048] The artificial leather raw material thus prepared can be dyed. For dyeing, it is preferable to use a liquid jet dyeing machine that can dye under a relatively low tension due to the brushing effect during the dyeing operation and the dyeing can be performed without impairing the extensibility of the polyurethane fiber. . As the jet dyeing method, for example, the jet dyeing method described in JP-A-07-229071 can be applied. However, dyeing under conditions where the nozzle pressure is too high or strong tension is applied,
Polyurethane fiber constituent polymer "flows" and "embrittles", which causes "power down" and "extension" defects of polyurethane fiber, which may impair stretchability and damage the fabric, resulting in product value Impair. Liquor dyeing
The appropriate nozzle pressure range for the color is 0.5-3.0 Kg / c
m ² . If the dyeing is carried out within a proper nozzle pressure range, the polyurethane resin hardly falls off, and contamination and physical properties of the dropped polyurethane resin do not occur.

The measured values referred to in the examples and comparative examples are based on the following measuring methods. (1) Measurement of average particle diameter: Measured at a disk rotation speed of 3,000 rpm by a light transmission centrifugal sedimentation method using water as a dispersion medium, using an automatic particle diameter measuring device manufactured by Horiba, Ltd. The average particle diameter is represented by a volume-based median diameter.

(2) Measurement of DMF dissolution rate: A stock solution of aqueous polyurethane resin emulsion (solid content: 30 to 40% by weight) is coated on a glass plate with a 0.25 mm applicator, and dried at 25 ° C. at room temperature for 20 hours. And made a film. After placing the film together with the glass plate in a hot air dryer at 120 ° C. and heat-treating for 20 minutes, the polyurethane film was peeled off from the glass plate and the weight (W1) of a sample cut into a 10 cm square size was measured. Then DMF
After being immersed in the stock solution (25 ° C.) for 6 hours, it is dried in a drier at 60 ° C. and its weight (W2) is measured. The dissolution rate was determined from the weight loss excluding the surfactant in the polyurethane resin.

(3) Measurement of Adhesion: A heat-treated film heat-treated in the same manner as in the above (2) was prepared. This polyurethane film was immersed in hot water at 130 ° C for 30 minutes, assuming a dyeing process.
After treatment for 2 minutes, sodium hydroxide and thiourea dioxide, 2 each
g / L for 15 minutes at 80 ° C.
It was dried in a dryer at 0 ° C. On top of this film,
Nonwoven sheets made of ultrafine fiber polyester of 5d / f or less are stacked, sandwiched between glass plates,
Treated in a hot air dryer at 130 ° C. for 30 minutes. At this time, the weight of the glass plate applied to the film was 15 g / cm ²
And was fixed. An integrated product of the film and the nonwoven fabric sheet was taken out, cut into a width of 2.5 cm, and the strength of the bonded surface was measured by a tensile strength / elongation measuring instrument.

(4) Measurement of calorific value and top temperature of exothermic peak: Differential scanning calorimeter (DSC, for example, SEIKO
I & E DSC200 / TG / DTA200), sample weight 5 to 10 mg, heating rate 10 ° C./min,
The temperature was raised to 300 ° C. by an air flow, and the expression peak was analyzed. The urethane resin film as a measurement sample is a stock solution of an emulsion (solid content: 35 to 40% by weight)
Is coated on a glass plate with a 0.75 mm applicator and dried at room temperature of 25 ° C. for 20 hours to form a film. Then, put the above film together with the glass plate in a hot air dryer at 130 ° C., heat-treat for 20 minutes, peel off the polyurethane film from the glass plate, treat in hot water at 130 ° C. for 20 minutes, and then treat at 80 ° C. for 15 minutes. After washing with water, a sample obtained by air-drying was used.

(5) Measurement of adhesive strength: A 0.05 mm thick stainless steel plate (SUS
304), and treated with a hot air drier at 180 ° C. for 20 minutes. Then, the stainless steel plate was cut into a width of 2 cm, and the strength of the bonded surface was measured with a tensile strength and elongation measuring device. At this time, a tape or the like is attached to the urethane film to be peeled to stop the elongation of the film, so that the measurement accuracy is improved.

(6) Measurement of 500 g load elongation: JIS-L-1096 elongation rate (constant speed elongation method) 4.90 ｛0.5K
The extension ratio under a load of gf｝ was determined. (7) Measurement of elongation recovery rate: Measured three times in accordance with JIS-L-1096 repetitive constant speed constant elongation method (20% constant elongation). The results are shown as the third measurement.

(8) Evaluation of dynamic repetitive extension characteristics (dynamic bagging test): Dynamic bagging test device Dynamic repetition was performed using a dynamic bagging test device devised with reference to a dematcher tester (JIS-L-1061). The elongation properties were evaluated. 1 and 2 are schematic explanatory diagrams of the structure and operation of the dynamic bagging test device. The dynamic bagging test device is a device that repeatedly applies a bending motion simulating an elbow bending operation to a sample piece of artificial leather, and a sample attached to a pseudo elbow (10) described later is connected to a lower chuck (2) of the sample (S). The upper and lower ends are positioned and fixed and set with a gripping distance C between the upper chuck (1) and the pseudo elbow is moved up and down with the lower chuck 2 toward the upper chuck to bend the pseudo elbow a predetermined number of times. (See the operation explanatory diagram of FIG. 2). The lower chuck (2) and the upper chuck (1)
Rods (5), (5 ') with the top plate (3) fixed to the upper end
The top plate (3) is rotatably supported on the upper chuck (1) and the upper end is rotatably supported on a screw rod (4a) fixed to the handle (4). By setting the distance A to the upper chuck (1) by rotating the handle (4), the bending angle of the pseudo elbow, that is, the bending angle of the sample piece along the top and bottom of the machine can be set to a predetermined value. Have been. The vertical movement of the lower chuck (2) is driven by the vertical movement of the crank (7) due to the rotation of the wheel (6).

As shown in FIG. 3, the pseudo elbow (10) has two pieces each having a thickness of 1 mm, a length of 140 mm, and a width of 18 m.
m is rotatably connected around a pin (11b) at one end to form a frame (11) having a length of 270 mm. A 68 mm-diameter cotton form cylindrical body in which a tricot of a 20 mm square polyester fiber is packed, and has a structure which is bent at the center thereof with the connecting pin as a fulcrum. The measurement sample is sewn into a cylindrical shape, inserted into the pseudo elbow, and fixed at both ends of the frame to the lower chuck (2) and the upper chuck (1) (a fixture is not shown).

Preparation of sample: Artificial leather was vertically 300 m long
It is prepared by cutting it into a rectangle of mx horizontal 235 mm (a grid mark of 0.5 mm is provided on the sample), and sewing the sample along the inner side 10 mm with the long side of the sample piece overlapped. You. One sample each of which length direction (300 mm) corresponds to the longitudinal / weft direction of the artificial leather was collected.

Test method: The sample was inserted into the simulated elbow shown in FIG. 3 and mounted on the simulated elbow. Next, the pseudo elbow on which the sample was mounted was set straight so that the distance between the lower chuck (2) and the upper chuck (1) was 275 mm. The pseudo elbow on which the sample is mounted is shaped like a “ku” (the space between the sample fixing parts at the time of the maximum bending is 175 mm, the elbow angle is 120 degrees at the maximum, and the inner angle is 60 degrees).
1) to bend until it reaches
10,000 cycles at a bending speed of 100 rpm
Repeated times.

Dynamic Bagging Measurement Results: Immediately after the completion of the dynamic bagging test, the area of a portion that protruded from the plane due to the removal of the test sample was determined, and this was defined as the dynamic bagging A value. After being left for 24 hours, the area of the portion that bulged out of the plane due to the detachment was determined and defined as the dynamic bagging B value. The correspondence between the measured values and the evaluation results visually is as follows.

Area of missing portion Visual observation result Judgment 40 cm ² or more The missing portion is conspicuous. XX: The part where 30 to 40 cm ^{2 is} missing can be seen. × 20-30 cm ² can be seen if attention is paid. △ 20 cm ² or less. ○

[0061]

EXAMPLES Example 1 An elastic fabric was prepared by weaving a plain fabric using 100d / 48f polyester filament as the warp and polyurethane elastic composite yarn as the weft. The polyurethane elastic composite yarn used is
Polyether urethane fiber 20d / 1f (Polyurethane elastic yarn manufactured by Asahi Kasei Kogyo Co., Ltd., product name: Roica) 75d
A polyurethane elastic composite yarn in which a single / 36f polyester filament was covered was used. 17 greige fabrics
Set greige for 20 seconds at 0 ° C, then 60, 80, 10
After 3 steps of relaxation at 0 ° C, spread 180
C., through a dryer for 30 seconds, a finished elastic plain woven fabric having a basis weight of 61 g / m 2 (woven density, warp: 49 yarns / 2.54 cm ² ,
Latitude: 54 lines / 2.54 cm ² ).

On the other hand, ultrafine short fibers of polyethylene terephthalate ultrafine fibers (PET ultrafine fibers) of 0.1 d denier obtained by the direct spinning method were cut to a length of 5 mm by a rotary cutter, and the ultrafine short fibers were put in water. The slurry was dispersed and used as a slurry for papermaking. The slurry was made into a nonwoven fabric sheet having a basis weight of 50 g / m ² . The nonwoven fabric sheet was laminated on both sides of the elastic plain fabric, and three-dimensionally entangled and integrated by high-speed water jet. The high-speed water flow was jetted at a pressure of 30 kg / cm ² from a swinging 0.2 mm nozzle. The laminated sheet has a suction device on the lower surface 80
It was placed on a mesh wire net and was collided with a high-pressure water stream at a position 30 mm from the nozzle. This operation was repeated four times for each of the front and back sides of the laminated sheet, and the basis weight was 160 g / m2 and the thickness was 0.5.
A 5 mm nonwoven fabric sheet was manufactured.

The surface of this nonwoven sheet was buffed using # 400 emery paper at a paper speed of 1000 m / min. Next, an aqueous polyurethane “AP-12” (manufactured by Nichika Chemical Co., Ltd.)
A solid polyether-based polyurethane emulsion having a solid content of 40 (%) and an average particle diameter of 0.6 μm. The resin content in the polyurethane emulsion solution was 9% by weight. As a heat-sensitive agent, 4% by weight of Na ₂ SO ₄ , and Chimasorb 944LD ( Impregnated with a mixed solution containing 1.0% by weight (trade name, antioxidant manufactured by Ciba-Geigy), and a pickup rate of 120 using a mangle.
(%), And then heated at 130 ° C. for 3 minutes with a pin tenter dryer. The performance of the aqueous urethane resin film used was as follows: DMF dissolution rate: 7%, adhesive strength: A1.0
(G / cm), calorific value 39 mj / mg, peak temperature 22
8 ° C. and adhesive strength B600 (g / cm).

The artificial leather thus obtained was subjected to a jet dyeing machine set in a 70-liter bath so as to have a bath ratio of 1:30, at a nozzle pressure of 1.3 g / cm and a blue-based disperse dye of 10%. Staining was performed at 130 (° C.) for 20 minutes at a concentration of owf%. Then, thiourea dioxide and caustic soda each 2 g / l
At 80 (° C.) for 15 minutes, followed by washing with water and drying. The jet dyeing machine uses the strainer (# 2
0) had almost no deposits, and could be easily cleaned by washing with water. Table 1 shows the test and evaluation results of the artificial leather after the dyeing finish.

Example 2 50% of the weft yarn of Example 1 was the polyurethane elastic composite yarn of Example 1, and the remaining 50% was 100d / 48f polyester multifilament. m ² of the finished plain weave elastic fabric (density,
Latitude: 48 lines / 2.54cm, Latitude: 56 lines / 2.54c
m) was prepared. The plain woven elastic fabric was subjected to the same methods, conditions, and operations as in Example 1 to obtain artificial leather having dyed finishes showing the test and evaluation results listed in Table 1 for artificial leather.

Example 3 The same finishing method as in Example 1 was applied, except that 25% (%) of the weft of Example 1 was the polyurethane elastic composite yarn of Example 1, and the remaining 75% was 100d / 48f polyester multifilament. Then, a plain woven fabric (density, warp: 48 yarns / 2.54 cm, weft: 57 yarns / 2.54 cm) having a finish basis weight of 58 g / m ² was prepared, and the same method as in Example 1 was used. Through the conditions and operations, artificial leather having dyed finish showing the test and evaluation results listed in Table 1 of the artificial leather was obtained.

Comparative Example 1 A plain woven fabric (density, warp: 47 g / m ²⁾ made of 100d / 48f polyester filament yarn in warp and weft.
Book / 2.54 cm, weft: 60 books / 2.54 cm), and the same procedures, conditions and operations as in Example 1 were carried out, except that the greige machine was not set.
A dye-finished artificial leather showing the evaluation results was obtained.

Comparative Example 2 Crisbon instead of water-based polyurethane emulsion
Artificial leather was prepared according to Example 1 except that 1836-P (trade name, solution type polyurethane resin manufactured by Dainippon Ink and Chemicals, Inc., resin solid content: 35% by weight) was used. Comparative Example 3 Instead of the water-based polyurethane emulsion of Example 1,
An artificial leather was prepared in the same manner as in Example 1 except that 9% by weight of Superflex (trade name, polyether-based aqueous polyurethane emulsion manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content: 40% by weight) was used. . The aqueous polyurethane resin used had a DMF dissolution rate of 16% and an adhesive strength A of 3.
5 g / cm, calorific value 80 mj / mg, peak temperature 1
At 90 ° C., the adhesive strength B was 847 g / cm.

In this artificial leather, the polyurethane resin was remarkably dropped off during dyeing, and about 40% by weight of the amount of resin adhering to the artificial leather raw material was dropped off. It had no product value at all. In addition, a large amount of sticky brownish deposits adhere to the strainer (# 20) of the jet dyeing machine.
Unless it was strongly rubbed with a wire brush, the attached matter could not be removed.

[0070]

[Table 1]

In Table 1, 20% weft elongation and bagging value B
(Area cm ^{2 of} a portion raised from a flat surface after standing for 24 hours in a dynamic bagging test in a weft direction) is a measurement value indicating the durability of the artificial leather in stretching performance in the weft direction and durability in dynamic cyclic expansion and recovery. Table 1 shows a 20% weft recovery rate and a bagging value B in the examples of the present invention (the artificial woven fabric of the present invention having an elastic woven fabric using a polyurethane composite elastic yarn in at least 1/4 of the number constituting the weft in the core portion). In comparison with Comparative Example 1 (artificial leather having a woven fabric in which all of the wefts are inelastic yarns at the core), Example 2
0 (%) Elongation recovery rate is 92 to 87%, and bagging B value is 3
１５15 cm ² , whereas those of Comparative Example 1
2%, 34 cm ² . The durability of the stretchability and the dynamic repetitive elasticity recovery of the artificial leather of the present invention has been significantly improved, and when the artificial leather of the present invention is subjected to the repeated elongation in the weft direction, it slips off and sets. It is clear that this is a product that does not substantially occur.

[0072]

As described above, the artificial leather of the present invention has a good appearance, flexibility, texture, and other sensibility, and has a good repetitive elasticity. It is a cloth material from which outer clothing for women and men can be obtained. The artificial comparison with excellent repetitive elasticity provided by the present invention is that the women's outer garment made with this is worn for one day and then hung on a hanger overnight, so that the part where slipping or sagging occurs is easy. It is excellent in easy care, that is, restored to the shape before wearing, and the silhouette at the time of production can be maintained for a long time. In addition, the present invention has the same or more stretchability without the need to insert a width unlike conventional products, so that a wider design can be designed, and the molding efficiency at the time of cutting is improved. As a result, it has become possible to provide artificial leather with high commercial value as an outer fabric that meets the demands of fashion.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a dynamic bagging test apparatus for performing a dynamic cyclic stretching recovery test of artificial leather.

FIG. 2 is an explanatory view of a bending operation of the explanatory view of the dynamic bagging test device shown in FIG. 1;

FIG. 3 is an explanatory view of a structure and a bending action of a pseudo elbow.

[Explanation of symbols]

 100: dynamic bagging test apparatus 10: pseudo elbow S: sample 2: lower chuck 1: upper chuck A: distance between top plate and upper chuck B: distance change scale (minimum position) C: sample gripping distance (initial sample length) D ···············································································································

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tamotsu Hayasaki 1-2-6 Dojimahama, Kita-ku, Osaka-shi, Osaka Asahi Kasei Kogyo Co., Ltd. F-term (reference) 4F055 AA01 AA27 EA09 EA11 EA14 EA22 EA28 EA33 FA15 4L047 AA25 AB08 BA04 BC12 CA04 CB10 CC02

Claims (7)

[Claims] An ultrafine fiber entangled body layer of 0.5 denier or less has at least 1/4 of the number of wefts interposed in its core.
Is bonded to an elastic woven fabric, which is a composite elastic yarn of a polyurethane fiber and an inelastic fiber, by three-dimensional entanglement with the ultrafine fibers in the ultrafine fiber entangled body layer, and the fabric structure is formed of an aqueous polyurethane resin. Artificial leather that has dynamic repetitive elastic stretching and recovery in the weft direction, which is filled with. 2. The artificial leather according to claim 1, wherein the polyurethane fiber is a polyether-based polyurethane fiber. 3. The artificial leather according to claim 1, wherein the fineness of the polyurethane fiber and the inelastic fiber constituting the composite elastic yarn is 10 to 100 denier and 20 to 200 denier, respectively. 4. The elastic woven fabric interposed in the core portion has a finishing weave density of 35 to 75 warps / 2.54 cm and a weft of 45 to 85 weaves /
The artificial leather according to claim 1, which is 2.54 cm. 5. The artificial leather according to claim 1, wherein the artificial leather has a dynamic bagging and B value in a weft direction of 30 (cm ² ) or less in dynamic repetitive elastic recovery. 6. An ultrafine fiber entangled body layer in which an ultrafine fiber web of 0.5 denier or less is laminated on both sides of an elastic woven fabric in which at least 1/4 of the number of wefts is organized by a composite elastic yarn of polyurethane fibers and inelastic fibers. And forming a sheet-like material obtained by entanglement and binding of a part of the ultrafine fibers with the elastic woven fabric, impregnating an aqueous polyurethane emulsion solution in which inorganic salts are dissolved and mixed, heating and drying. A method for producing artificial leather having dynamic cyclic elongation characteristics. 7. The inorganic salt is a neutral salt composed of an alkali metal or an alkaline earth metal, and is at least one inorganic salt selected from the group consisting of monovalent or divalent sulfates, nitrates and chlorides. 7. The method for producing an artificial leather having dynamic cyclic elasticity recovery properties according to claim 6.