JPH0320504B2 - - Google Patents

Description

[Detailed description of the invention]

<Industrial Application Field> The present invention relates to a fiber entangled nonwoven fabric with excellent elasticity. More specifically, it has excellent fiber entanglement, has a wide stretching range that does not substantially cause structural deformation or structural destruction even when repeatedly stretched and deformed, and is rich in stretchability, giving a sense of fulfillment. The present invention relates to a fiber-entangled nonwoven fabric that has a certain soft texture and is suitable as a substrate for artificial leather. <Conventional technology> Conventionally, as a fiber entangled nonwoven fabric with excellent elasticity,
Nonwoven fabrics have already been made by depositing short fibers obtained by flash spinning polyurethane and bonding fiber intersections using methods such as self-adhesion. In addition, a spunpond nonwoven fabric obtained by depositing long fibers obtained by spinning polyurethane was published in Japanese Patent Application Laid-Open No. 52-81177.
As a nonwoven fabric with elasticity and strength, a nonwoven fabric obtained by mixing 5 to 80% by weight of elastic fibers with inelastic fibers is disclosed in Japanese Patent Application Laid-open No. 18579/1983, which is a composite of an inelastic polymer and an elastic polymer. JP-A-52-85575 discloses a method in which composite fibers obtained by spinning are used to form a fiber-entangled nonwoven fabric, and then the composite fibers are separated into each component. The mixed fiber obtained by mixing and spinning two types of non-elastic polymers are mixed to make a non-woven fabric, at least one type of non-elastic polymer in the mixed fiber is dissolved, and then the dissolved non-elastic polymer is mixed. Japanese Patent Publication No. 40-2792 proposes a method for manufacturing a leather-like sheet by directly coagulating an elastic polymer solution into a nonwoven fabric. <Problems to be Solved by the Invention> In the conventional manufacturing method of fiber entangled nonwoven fabric, in the case of a nonwoven fabric made of fibers made of an inelastic polymer, even if the nonwoven fabric is stretched by a slight amount, for example, by 10%, the fiber entangled structure is not formed. deformation occurs and never recovers to its original state. On the other hand, in the case of nonwoven fabrics made of fibers made of elastic polymers such as polyurethane elastomers, they exhibit stretch behavior up to a certain extent of elongation. It is extremely difficult to perform entanglement processing. Furthermore, fibers made of elastic polymers and fibers made of inelastic polymers have an incomparably large difference in stiffness, elongation, and flexural modulus, so it is necessary to mix both fibers. It is quite difficult to make a good fiber web, let alone hang it on a card. In addition, there is a method for manufacturing nonwoven fabric in which a fiber-entangled nonwoven fabric is made using composite fibers obtained by composite spinning of an inelastic polymer and an elastic polymer, and then each component is peeled off. The fibers are constrained in the same state and sufficient stretchability cannot be obtained. Furthermore, as in the past, a fiber-entangled nonwoven fabric of inelastic fibers containing an elastic polymer has elasticity within the range of deformation that occurs between the fixed points of the entangled fibers, and the range is not large. The present invention has excellent fiber entanglement properties, has a wide stretching range that does not substantially cause structural deformation or structural destruction even when repeatedly stretched and deformed, has high elasticity, and has a soft texture with a sense of fulfillment. Therefore, it is an object of the present invention to provide a fiber-entangled nonwoven fabric suitable as a substrate for artificial leather having elasticity. <Means for Solving the Problems> The present invention provides ultrafine fibers consisting of short fibers of modified elastic fibers A, which are ultrafine fiber bundle fibers or fibers having micro spaces, made of an elastic polymer A mainly composed of polyurethane elastomer, and an inelastic polymer B. A fiber entangled nonwoven fabric formed by kneading and three-dimensionally entangling short fibers of modified inelastic fibers B, which are fiber bundle fibers or fibers having microscopic spaces, in which the entangled state of the fibers in the nonwoven fabric is The modified inelastic fiber B is a fiber entangled nonwoven fabric characterized in that it is formed by being bent and bent by the modified elastic fiber A in a tensed entangled state and entangled in a loose tissue structure. Furthermore, the present invention comprises short fibers of modified elastic fibers A, which are made of an elastic polymer A mainly composed of polyurethane elastomer, and are fibers having ultrafine fiber bundles or micro spaces, and short fibers of modified elastic fibers A, which are made of an inelastic polymer B, and are ultrafine fiber bundle fibers or fibers having micro spaces. It is a fiber-entangled nonwoven fabric formed by three-dimensionally entangling the short fibers of the modified inelastic fibers B, which are the fibers with the modified inelastic fibers B, and the entangled state of the fibers in the nonwoven fabric is A polymer mainly composed of an elastic polymer is contained in the fiber entanglement space of the fiber entangled nonwoven fabric, which is formed by bending and bending the modified elastic fibers A in a tense entangled state and intertwining the loosened tissue structure. It is a fiber entangled nonwoven fabric characterized by the following. That is, the highly stretchable fiber-entangled nonwoven fabric of the present invention is made of an elastic polymer A mainly composed of polyurethane elastomer, and at least one type of non-elastic polymer C having a different solubility or degradability from the elastic polymer A. A fiber web is formed by mixing short fibers of a multicomponent fiber consisting of the following fibers and short fibers of a multicomponent fiber consisting of at least two types of inelastic polymers B and D having different solubility or degradability in a predetermined ratio. Then, the fibers are subjected to three-dimensional entanglement treatment to form a fiber entangled nonwoven fabric, and then the following steps (1), (2) and (3) are carried out. under conditions of low shrinkage or no shrinkage.
(2) removing the inelastic polymer C from the multicomponent fibers and at least one type of inelastic polymer D from the multicomponent fibers, or converting the multicomponent fibers into each component; (3) impregnating a nonwoven fabric with a solution or dispersion of a polymer mainly composed of an elastic polymer and solidifying it; i.e., process (1) → process (2) ), process (2) → process (1), process (1) and process (2) at the same time, further, process (1) → process (2) → process
(3), Process (1) → Process (3) → Process (2) or Process (1) and Process
(2) at the same time → step (3), and then heat-treated at a temperature of 80 to 170°C for at least 3 minutes, an elastic polymer A mainly composed of polyurethane elastomer Fiber-entangled nonwoven fabric or elastic polymer of modified elastic fibers A, which are ultrafine fiber bundle fibers or fibers with micro spaces, and modified inelastic fibers B, which are ultrafine fiber bundle fibers or fibers with micro spaces, and inelastic polymer B. This is a method for producing a fiber-entangled nonwoven fabric with excellent elasticity, characterized in that the fiber-entangled nonwoven fabric contains a polymer mainly composed of. The raw material fibers constituting the stretchable fiber-entangled nonwoven fabric of the present invention include an elastic polymer A mainly composed of polyurethane elastomer, and at least one non-elastic polymer having a different solubility or degradability from the elastic polymer A. A multicomponent fiber obtained by spinning C.
A multicomponent fiber obtained by spinning at least two types of inelastic polymers B and D having different solubility or degradability is used. In the present invention, by using multicomponent fibers, physical properties such as elongation behavior, stiffness, and flexural modulus of the fibers are similar to or within the same range as those of multicomponent fibers, so that the blendability and carding properties of both fibers are improved. A fiber web with good homogeneity can be obtained, and a good fiber entanglement state can be obtained by a three-dimensional fiber entanglement method such as a needle punching method or a high-pressure fluid injection method. In addition, in the present invention, the elastic polymer refers to fibers obtained by spinning the elastic polymer at room temperature.
It refers to a polymer that has been stretched by 50% and has an elongation elastic recovery rate of 90% or more 1 minute after the elongation is released, and an inelastic polymer is a low elongation polymer that has an elongation elastic recovery rate of 50% or less when measured in the same manner. Indicates a polymer whose elastic recovery rate or critical elongation rate does not reach 50% at room temperature. The elastic polymer A of the multicomponent fiber used in the present invention is selected from the group of polymer diols such as polyester diol, polyether diol, polyester ether diol, polylactone diol, polycarbonate diol, etc., having an average molecular weight of 500 to 3500. at least one type selected from the group of organic diisocyanates such as diisocyanates having an aromatic ring, aliphatic or alicyclic diisocyanates, low molecular weight diols, aliphatic or alicyclic diamines,
At least one type of polyurethane elastomer selected from polyurethane elastomers obtained by reacting an active hydrogen atom such as hydrazine or a diamine having an aromatic ring with at least one type selected from the group of two chain extenders. Further, the elastic polymer is mainly composed of a polyurethane elastomer mixed with a conjugated diene polymer such as polyisoprene or polybutadiene, or other spinnable elastic polymers as required. On the other hand, the inelastic polymer C of the multicomponent fiber is a polymer that can be removed by treatment with a solvent or decomposition agent different from that of the elastic polymer A, such as polyethylene, ethylene copolymer, polypropylene, polybutene, etc. At least one type of polymer selected from the group of polyolefins such as ethylene vinyl acetate copolymers, polystyrene or styrene copolymers, polyvinyl chloride or vinyl chloride copolymers, polyesters, polyamides, polycarbonates, etc. The method for producing multicomponent fibers involves combining an elastic polymer A and an inelastic polymer C, which uses a different solvent or decomposition agent than the elastic polymer, and whose thermoforming temperature ranges overlap.
or can be dissolved in a common or compatible solvent, and remain soluble for the time required for spinning, and do not cause reactions or interactions that would impede spinning or removal of the inelastic polymer from the fiber. Polymer combinations, such as polyurethane/polyolefin or olefin copolymer, polyurethane/polystyrene or styrene copolymer, polyurethane/polyolefin/polystyrene, polyurethane/polyamide or polyester, polyurethane/conjugated diene polymer/polystyrene or styrene copolymer Examples include. The proportion of elastic polymer A in the multicomponent fiber is 30 to 80% by weight, preferably 40 to 70% by weight. The selected elastic polymer A and inelastic polymer C are dissolved in a common solvent and spun by a wet spinning method or a dry spinning method, or melt spun at a common melting temperature. That is, a method in which elastic polymer A and inelastic polymer C are melted in the same melting system or melted in the same melting system and then spun, or melted in different melting systems or melted in different melting systems and alternately formed into multiple layers. Multi-component fibers are spun by combining them at a spinning head or spinneret with a structure that forms a fiber cross-sectional shape of a sea-island type or a composite type in which one side is a dispersion medium component and the other is a large number of dispersed components. Fibers are produced (the same spinning method is used to produce multicomponent fibers, which will be described later). Then,
The multicomponent fibers are preferably drawn to at least twice the length of the spun fibrils under conditions such as dry heat, wet heat or heated water. When the stretching ratio is high, highly shrinkable fibers can be obtained, and even when made into a fiber-entangled nonwoven fabric, a fabric with a high sense of fullness and high elasticity can be obtained. The drawn fibers are crimped and cut into fiber lengths of 20 to 100 mm to obtain short multicomponent fibers. The elastic behavior of this multicomponent fiber is suppressed by the elastic polymer, and it falls within the range of fiber physical properties such as stiffness and elongation behavior of ordinary inelastic fibers, especially multicomponent fibers.
It can be handled in the same way as multicomponent fibers. In addition, the inelastic polymer B used as the fiber component of the other multicomponent fiber constituting the fiber-entangled nonwoven fabric is, for example, a polyester such as polyethylene terephthalate or ethylene terephthalate copolymer, polybutylene terephthalate or butylene terephthalate copolymer. , nylon-6, nylon-66, nylon-610, nylon-12, polyamides such as polyamides containing aromatic rings, polyolefins such as polyethylene and polypropylene, saponified products of ethylene-vinyl acetate copolymers, polyvinyl alcohol, acrylic copolymers It is at least one type of polymer selected from the group such as polymers. On the other hand, the polymer D that is finally removed
Examples include polymers that are soluble in solvents or decomposed with decomposing agents, such as polyethylene or ethylene copolymers, ethylene vinyl acetate copolymers or partially saponified products thereof, polystyrene or styrene copolymers, polyesters, polyamides, polyvinyl alcohol, At least one selected from the group such as polyvinyl chloride or vinyl chloride copolymer
It is a type of polymer. Then, the inelastic polymer B used as the fiber component and the inelastic polymer D as the removed component are combined and spun. However, when the multicomponent fiber is a splittable fiber, at least two types of inelastic polymers B having low or no compatibility and different physical properties are combined and spun. Specific polymer combinations include, for example, polyethylene terephthalate/polyethylene or ethylene copolymer, polyethylene terephthalate/polystyrene or styrene copolymer, polybutylene terephthalate/polyethylene or ethylene copolymer, polybutylene terephthalate/polystyrene or styrene copolymer. Combined, nylon-6 or nylon-
610・Polyethylene or ethylene copolymer,
Examples include polyethylene terephthalate or polybutylene terephthalate, nylon-6 or nylon-610, polypropylene, polystyrene, or polyethylene. The proportion of inelastic polymer B as a fiber component is 40 to 85% by weight. The spinning method is similar to that for the multicomponent fibers described above, and the fibers are spun, drawn, crimped, and cut to obtain short multicomponent fibers. Next, the multicomponent fibers and the multicomponent fibers are mixed. The blending ratio is determined by the desired physical properties of the fiber-entangled nonwoven fabric, but in general, multicomponent fibers are
~80% by weight, preferably 20-70% by weight. If the amount of multicomponent fibers is small, the elasticity will be low but it will be flexible, and if the multicomponent fibers are large, the elasticity will be large and the feeling of fullness will be greater. Furthermore, if necessary, regenerated cellulose fibers, natural fibers, and chemical fibers may be mixed in an amount of approximately 25% by weight or less within a range that does not impede stretchability. After mixing multi-component fibers with multi-component fibers,
The fibers are defibrated using a card, passed through a web to form a random web or cross-lap web, and the resulting fiber webs are laminated to a desired weight and thickness. The weight of the fibrous web generally ranges from 100 to 2000 g/ ^m2 . Next, the fiber web is subjected to a three-dimensional fiber entanglement treatment using a known method to obtain a fiber entangled nonwoven fabric.
A preferred method for entangling the fibers is three-dimensional entanglement by a needle punching method or a high-pressure water jet method, either alone or in combination. In general, the needle punching method processes the number of punches in the range of 200 to 2,500 punches/ ^cm2 , and the high-pressure water jet method processes the water pressure of 15
The treatment is carried out 3 to 10 times using a columnar flow of ~100 Kg/cm ² , and it is preferable that the three-dimensional entanglement of the fibers is sufficiently performed in terms of elasticity and fullness. In order to impart sufficient stretchability to the obtained fiber-entangled nonwoven fabric, the fiber-entangled nonwoven fabric must be contracted. In the shrinkage treatment method, the area of the fiber-entangled nonwoven fabric is reduced by treating the multicomponent fibers in a dry heat atmosphere, moist heat atmosphere, or hot water under conditions in which the multicomponent fibers are sufficiently shrunk but the multicomponent fibers are low or non-shrinkable.
Deflate by 10-80%. This shrinkage treatment of the fiber-entangled nonwoven fabric may be performed before or after removing the inelastic polymer component from the multicomponent fibers, or while the nonwoven fabric contains an elastic polymer.
The desired shrinkage range can be obtained by setting the conditions in each case. Through this shrinkage treatment, the modified elastic fiber A made of the multicomponent fiber or the elastic polymer A obtained therefrom is greatly shrunk, and the modified inelastic fiber B made of the multicomponent fiber or the inelastic polymer B obtained therefrom is accompanied by this.
is folded or bent, resulting in a loose fibrous structure within the nonwoven fabric. The shrinkage rate of this fiber-entangled nonwoven fabric can be adjusted by the shrinkage treatment conditions (e.g., temperature, time, tension, etc.), but the potential shrinkage (maximum shrinkage rate) of the fiber-entangled nonwoven fabric is The type of elastic polymer, the molecular structure of the polymer, the spinning conditions,
It is controlled by the draw ratio, fineness, etc.; on the other hand, the bending stiffness of the fiber is determined by the type of inelastic polymer of the multicomponent fiber, the degree of orientation, the fineness, etc., and the blending ratio of multicomponent fiber and multicomponent fiber. Therefore, it is mainly decided. Therefore, by changing these conditions, the shrinkage rate of the fiber-entangled nonwoven fabric can be changed as desired. Furthermore, in order to impart elasticity to the fiber-entangled nonwoven fabric, it is necessary to remove the inelastic polymer fiber component of the multicomponent fibers to obtain modified elastic fibers A, which are microfiber bundle fibers or fibers having microscopic spaces. On the other hand, at least one type of inelastic polymer fiber component of the multicomponent fiber is removed to change the fiber form to ultrafine fiber bundle fibers or modified inelastic fiber B, which is a fiber with micro spaces, or the multicomponent fiber is also modified with each component. By peeling and dividing the ultrafine fiber bundle fibers into modified inelastic fibers B, a fiber-entangled nonwoven fabric with greater flexibility and stretchability can be obtained. The method for removing the inelastic polymer fiber component is carried out by treating the elastic polymer fiber component and the utilized inelastic polymer fiber component with a non-solvent or non-degrading agent that is a solvent or a decomposing agent for other fiber components. For example, toluene, trichlorethylene, perchlorethylene, etc. are used for polyurethane/polyolefin or polystyrene fibers, calcium chloride/methanol solution is used for polyurethane/polyamide fibers, and cyclohexanone is used for polyunthane/polyvinyl chloride fibers. In this invention, fibers obtained by removing one component from a multicomponent fiber or fibers obtained by processing a multicomponent fiber and dividing it into a large number of ultrafine fibers are referred to as "modified fibers" in the present invention. Modified fibers may be modified fibers in the final product, even if they are fibers that do not take the form of glued and distinct microfiber bundle fibers or fibers with microscopic spaces, such as polyurethane fibers. Any clear fibers are fine. The process of converting multicomponent fibers into modified fibers may be performed in the same process or in separate processes. You can do it later. However, in view of the simplicity of the process, it is preferable to carry out the same process. In the fiber-entangled nonwoven fabric made of modified fibers of the present invention, when a stretching force is applied to the fiber-entangled nonwoven fabric, a large force is not required because initially only the force to stretch the modified elastic fibers A is applied. As the modified inelastic fibers B begin to deform, a larger force is gradually required. Therefore, there is a wide range until the fixation due to the entanglement of the fiber-entangled nonwoven fabric, the fixation between the fibers due to the adhesion of the modified elastic fibers A, or the fixation due to the binder is removed, that is, the range until structural destruction occurs, and during this period, there is a substantial Stretchability can be imparted to the material without causing structural damage. Further, the fiber-entangled nonwoven fabric of the present invention may contain a binder resin made of an elastic polymer within a range that does not impede stretchability. The elastic polymer used as the binder resin is, for example, at least one type selected from the group of polymer diols such as polyester diol, polyether diol, polyester ether diol, polylactone diol, and polycarbonate diol, and at least one type of organic diisocyanate. and polyurethane obtained by reacting a low-molecular compound having at least two active hydrogen atoms as a chain extender, a polymer or copolymer of acrylic acid or acrylic ester, a conjugated diene polymer such as polyisoprene, polybutadiene, etc. , styrene-butadiene copolymer, acrylonitrile-butadiene copolymer, and the like. The elastomeric polymer is impregnated into a nonwoven fabric using a solution dissolved in a solvent that does not attack the fibers or a dispersion in a dispersant, and treated with a solvent that does not attack the fibers and the elastomer - non-solvent, in a non-solvent, or in a salt aqueous solution. or solidify by evaporating the solvent or dispersant. By incorporating an elastic polymer into the fiber-entangled nonwoven fabric, the performance range of the fiber-entangled nonwoven fabric such as flexibility, stretchability, and texture can be expanded. The fiber-entangled nonwoven fabric of the present invention can be sliced into desired thicknesses to have a constant thickness, one or both sides can be buffed with sandpaper etc. to a constant thickness, or the fiber-entangled nonwoven fabric can be made as is. Use as a product. The fiber entangled nonwoven fabric of the present invention is a modified elastic fiber A made of an elastic polymer.
The short fibers of modified inelastic fiber B made of an inelastic polymer are almost uniformly mixed and entangled in three dimensions, and the entangled state of the fibers is modified. This is a nonwoven fabric that is bent and bent by the elastic fibers A and intertwined in a loose tissue structure as a whole, or a nonwoven fabric that contains an elastic polymer in the nonwoven fabric. One way to check the state of this tissue structure is to check the shape of the nonwoven fabric after removing one of the fibers from the fiber-entangled nonwoven fabric. That is, when the modified elastic fibers A of the elastic polymer are dissolved or decomposed and removed, the fiber entangled nonwoven fabric of the modified inelastic fibers B of the inelastic polymer is released from tension and expands to an area close to that before the shrinkage treatment. On the other hand, when the modified inelastic fibers B of the non-elastic polymer of the nonwoven fabric are removed by dissolving or decomposing, the area of the fiber-entangled nonwoven fabric of the modified elastic fiber A of the elastic polymer will hardly change or the area change will remain small. You can know from this. Due to the structure of the above-mentioned fiber-entangled nonwoven fabric, it has a large elongation range that does not substantially cause structural deformation or structural destruction even after repeated elongation deformation, usually about 15 to 50% elongation, It also has a rich elasticity and a flexible texture that gives a sense of fulfillment. The fiber-entangled nonwoven fabric of the present invention can be ironed on the surface to give it a smooth surface, or can be finished with a silver surface by forming or adding a film of an elastic polymer on the surface to make a grain-finished leather-like sheet. The surface can be finished with fiber raising treatment to produce a suede-like leather-like sheet. The fiber-entangled nonwoven fabric of the present invention has many useful uses such as supporters, bands, medical supplies, clothing or parts for clothing, leather-like sheets for interior use, outer clothing, car seats, and many others. <Examples> Next, embodiments of the present invention will be described using specific examples, but the present invention is not limited to these examples. Note that parts and percentages in the examples are by weight unless otherwise specified. Examples 1 to 4, Comparative Examples 1 and 2 Polyester polyurethane (elongation elastic recovery rate
A bicomponent fiber with polyethylene as the sea component, consisting of 60 parts of 100%) and 40 parts of low-density polyethylene (50% unstretched), was made using a melt-spinning method, stretched 2.8 times,
The fibers were crimped and cut into fiber lengths of 51 mm to obtain staple fibers with a fineness of 6 denier (hereinafter referred to as fiber ₁ ). On the other hand, nylon-6 (elongation elastic recovery rate less than 50%) 50
A bicomponent fiber consisting of 50 parts of low-density polyethylene and 50 parts of low-density polyethylene is produced using a melt-spinning method, drawn, heat treated, crimped, and cut into fiber lengths of 51 mm to produce staple fibers with a fineness of 4 denier (hereinafter referred to as fiber
₁ ) was obtained. Next, Fiber ₁ and Fiber ₁ are mixed in the ratio shown in Table 1, spread on a card, and then formed into a random web using a random webber.The fiber web is then combined alternately from both sides using a #40 needle. 560
A three-dimensional entanglement process was performed by needle punching at a punch/cm ² to produce a fiber entangled nonwoven fabric weighing approximately 400 g/m ² . This fiber-entangled nonwoven fabric was placed on a Teflon coating sheet and heated to 135°C under no tension.
The fiber-entangled nonwoven fabric was heat-treated in hot air to give shrinkage. The shrink-treated fiber-entangled nonwoven fabric was dipped in hot perchlorethylene at about 80°C and repeatedly squeezed to dissolve and remove the polyethylene, then air-dried to remove the solvent, and then subjected to dry heat treatment in hot air at about 130°C. Then, adhesive points were formed by adhesion in the areas where the polyurethane fibers were in contact with each other. The obtained fiber-entangled nonwoven fabric has polyurethane modified fibers and nylon-6 ultrafine fiber bundle fibers in a good mixed fiber state, and the fibers in which polyethylene has been dissolved become pliable and have many entangled knot points, making them good. Stretchability was obtained, and no structural deformation occurred even after 30% elongation. Table 1 shows the state of the obtained fiber-entangled nonwoven fabric. The fiber-entangled nonwoven fabric of the present invention was flexible and had little or no fiber texture peculiar to fiber-entangled nonwoven fabrics. The surfaces of the thick samples of Examples 1 and 2 were ironed to make them smooth, and the colored samples were materials that could be used for casual wear. It is also a thin material that can be used as a supporter. The surfaces of the samples of Examples 3 and 4 were subjected to a fluffing treatment to obtain a suede-like material.

[Table] As a result of enlarging and observing the fiber-entangled nonwoven fabric obtained in the above example, it was found that the polyurethane modified fibers were in a tense state, whereas the nylon-6 ultrafine fiber bundle fibers were in a relaxed state. Was. On the other hand, such a state was not observed in the fiber entangled nonwoven fabric of the comparative example. Examples 5 to 7, Comparative Example 3 Polyester polyurethane (elongation elastic recovery rate
100%) 60 parts and styrene copolymer (50% without elongation)
A bicomponent fiber consisting of 40 parts is made using a melt spinning method,
It was stretched 2.5 times, crimped, and cut into a fiber length of 51 mm to obtain a stable fiber (hereinafter referred to as fiber ₂ ) with a fineness of 6 denier. On the other hand, a bicomponent fiber consisting of 50 parts of polyethylene terephthalate (with an elongation elastic recovery rate of less than 50%) and 50 parts of low-density polyethylene, with polyethylene as the sea component, was made using a melt-spinning method, stretched, heat treated, crimped, and the fiber length was 51 mm. Cut into non-shrinkable staple fibers with a fineness of 4 denier (hereinafter referred to as fiber ₂ )
I got it. Next, Fiber ₂ and Fiber ₂ are mixed in the ratio shown in Table 2, and after being carded and defibrated, a cross-lap web is formed, and the fiber web is alternately rolled from both sides with a #40 needle for a total of 700 fibers. Three-dimensional entanglement processing is performed by needle punching of punch/ ^cm2 ,
A fiber-entangled nonwoven fabric weighing approximately 750 g/m ² was produced. This fiber-entangled nonwoven fabric was introduced into hot perchlorethylene at about 85°C in a non-tensioned state, and the styrene copolymer and polyethylene in the fibers were dissolved and removed, and the fiber-entangled nonwoven fabric was shrunk in the same treatment step. After squeezing out the solution, it was pressed and dried in hot air at about 80°C. The obtained fiber-entangled nonwoven fabric has adhesion points formed by adhesion in the areas where polyurethane fibers are in contact with each other, and the polyurethane fibers and ultra-fine polyethylene terephthalate fiber bundle fibers are in a good mixed state and are flexible, so fiber entanglement is not possible. It had many bonding nodes and exhibited good stretchability, and no structural deformation occurred even when stretched by 30%. Table 2 shows the state of the obtained fiber-entangled nonwoven fabric. When the state of the fibers of the fiber-entangled nonwoven fabrics obtained in these Examples was observed under magnification, Examples 1 to 4
It was the same.

[Table] Examples 8 to 11, Comparative Example 4 Polyester polyurethane (elongation elastic recovery rate
A bicomponent fiber consisting of 50 parts (100%) and 50 parts low-density polyethylene (50% unstretched), with polyethylene as the sea component, was made using a melt-spinning method, stretched 2.8 times, crimped, and cut to a fineness of 6. Raw cotton (hereinafter referred to as fiber ₃ ) with a denier and a fiber length of 51 mm was obtained. On the other hand, nylon-6 (elongation elastic recovery rate less than 50%)
A bicomponent fiber consisting of 50 parts of low-density polyethylene and 50 parts of the above-mentioned low-density polyethylene, with polyethylene as the sea component, is produced by a melt-spinning method, stretched, crimped, and cut to produce raw cotton (hereinafter referred to as fiber) with a fineness of 4 denier and a fiber length of 51 mm. ₃ )
I got it. Next, 40 parts of Fiber ₃ and 60 parts of Fiber ₃ are mixed, a random web is made by passing the card through it, and the web is three-dimensionally punched from both sides alternately with a #40 needle with a total of 420 punches/cm ^2. An entanglement treatment was performed to produce a fiber-entangled nonwoven fabric weighing approximately 500 g/m ² . This fiber-entangled nonwoven fabric was immersed in an aqueous polyurethane dispersion having a solid content of 4%, and then squeezed to a liquid content of 80% using a squeezing roll. Then, it was placed on a Teflon-coated sheet and dried in a hot air dryer at 130°C under substantially no tension. The dried fiber-entangled nonwoven fabric shrinks by approximately 35% in length in both the vertical and horizontal directions (area shrinkage rate is approximately 57%).
Was. Next, the fiber-entangled nonwoven fabric was immersed in perchloroethylene at 80°C to dissolve and remove the polyethylene in fibers ₃ and ₃ , and dried in a hot air dryer at about 80°C. The obtained polyurethane-containing fiber-entangled nonwoven fabric has a weight of approximately 630 g/m ² in which convergent fibers of polyurethane and fine denier fibers of nylon-6 are well entangled.
It was a sheet-like product with a final area shrinkage rate of about 60%. After slicing approximately the center of the sheet material's thickness with a band machine knife and dividing it into two parts, the sheet material is impregnated with a 5% aqueous solution of polyvinyl alcohol and dried to prevent elongation during subsequent processing of the sheet material. Ta. Then, the sliced surface was buffed with sandpaper to make the thickness uniform, and then the surface was buffed to create a suede-like surface with raised fibers of 0.6 mm in thickness. The obtained sheet material was dyed at a metal complex dye concentration of 2% owf. at a temperature of 90°C for 60 minutes.
After drying, the product was rubbed and the surface was brushed to obtain suede-like artificial leather (sample of Example 8).
This artificial leather had a writing effect, had high elasticity in both directions, was extremely flexible, and was resistant to wrinkles. In the same manufacturing method as above, fiber ₃ and fiber
Suede-like artificial leather was made by varying the blending ratio of ₃ as shown in Table 3. The properties of the obtained artificial leather are shown in Table 3. Furthermore, after repeating 30% elongation and recovery 10 times for the samples of each Example and the samples of Comparative Examples, the recovery rate was determined by leaving it for 33 hours. As a result, the samples of Examples 8 to 11 recovered 99 to 100%. On the other hand, the sample of Comparative Example 4 was 58%.

【table】

[Table] Furthermore, the artificial leather of Example 10 was extremely full-bodied and showed an elastic recovery rate of 95% even after 50% elongation. However, this artificial leather has too few naps to be used as suede-like artificial leather, so the surface
After smoothing by contacting the flat roll surface at 120°C, a 20% polyurethane aqueous dispersion was applied with a gravure roll, and a 10% polyurethane solution was further applied with a gravure roll. Then, the polyurethane-coated surface was embossed with a heated embossing roll to obtain silver-coated artificial leather. This artificial leather had a solid feel and excellent elasticity, making it suitable as a material for shoe uppers. As a result of enlarging and observing the state of the fibers inside the artificial leather obtained in these examples, it was found that the fibers (bundle) made of polyester polyurethane were in a tension state between the points fixed by the binder resin or the points fixed by entanglement. nylon-
It was confirmed that the ultrafine fiber bundle fibers consisting of 6 were in a loose state. Example 12 Polyester polyurethane (elongation elastic recovery rate
100%) 60 parts and polystyrene (50% unstretched) 40 parts
A two-component fiber with a fineness of 6 denier (hereinafter referred to as fiber ₄ ) obtained by melt-spinning 50 parts of polyethylene terephthalate (with an elongation elastic recovery rate of less than 50%) and 50 parts of the low-density polyethylene was melt-spun. Using a bicomponent fiber with a fineness of 4 denier (hereinafter referred to as fiber ₄ ) in which the obtained polyethylene is a sea component, 30 parts of this fiber ₄ and 70 parts of fiber ₄ are mixed to make a random web, and a tertiary web is made by needle punching. After being entangled and made into an entangled nonwoven fabric, the temperature is 90℃
The polystyrene and polyethylene in the fibers were dissolved and removed using perchloroethylene, and the fibers were dried in a hot air dryer at approximately 80°C. The obtained fiber-entangled nonwoven fabric had an area shrinkage rate of about 30%. Solid content concentration of 4% as a binder resin was added to the obtained fiber-entangled nonwoven fabric.
It was impregnated approximately 100% with an aqueous polyurethane dispersion, placed on a Teflon-coated sheet, and dried in a hot air dryer at a temperature of 130°C under no tension.
The obtained fiber-entangled nonwoven fabric was subjected to the same surface treatment and surface shaping/finishing as in Example 10 to produce silver-covered artificial leather. This artificial leather had a slightly high resilience, but was a material rich in flexibility and elasticity. In addition, the condition of the fibers inside this artificial leather was as follows in Examples 8 to 11.
Similarly, while the polyurethane fibers were in a taut state, the polyethylene terephthalate microfiber bundle fibers were in a relaxed state. Comparative Example 5 For comparison, the fibers ₄ obtained in Example 12 were passed through a hot water bath for free shrinkage, and then made into a random web in the same manner as in Example 12, and a fiber-entangled nonwoven fabric was prepared using polystyrene and polyethylene. was dissolved and removed, treated under hot air, and then a binder resin was applied. The obtained fiber-entangled nonwoven fabric was substantially free from shrinkage. The artificial leather obtained from this fiber-entangled nonwoven fabric has high resilience but low elasticity, and when stretched by 30%, the recovery rate was only 68%, resulting in structural destruction. Further, when the state of the fibers of this fiber-entangled nonwoven fabric was observed under magnification, there was almost no difference in the tension state between the fibers made of polyurethane and the fibers made of polyethylene terephthalate. Example 13 Bicomponent fiber with a fineness of 6 denier (hereinafter referred to as fiber ₅ ) obtained by melt-spinning 40 parts of low-density polyethylene and 60 parts of polyester polyurethane (100% elongation elastic recovery), and 50 parts of low-density polyethylene. 2 with a fineness of 4 dedenier and whose sea component is polyethylene obtained by melt-spinning 50 parts of nylon-6 and nylon-6.
Using component fibers (hereinafter referred to as fiber ₅ ), 20 parts of this fiber ₅ and 80 parts of fiber ₅ are mixed to make a cross-lap web, which is three-dimensionally entangled by needle punching to form a fiber-entangled nonwoven fabric. After that, it was placed on a fabric and passed through a hot air dryer at 135°C for heat treatment. The obtained fiber-entangled nonwoven fabric has an areal shrinkage rate of approximately
20%, apparent density 0.40, some of the polyethylene fibers were fused at fiber intersections, resulting in a somewhat plate-like hardness. This heat-treated fiber-entangled nonwoven fabric is coated with a dimethylformamide solution containing polyether polyurethane at a concentration of 10% (however, this solution contains 1% water. By containing 1% water, the fibers are formed. (The polyurethane in the solution is not attacked by the dimethylformamide solvent, and the polyurethane in the solution is not substantially coagulated.)
The polyethylene was then dissolved and removed in toluene at a temperature of 90°C. The obtained fiber-entangled nonwoven fabric was buffed with sandpaper, dyed,
Finishing treatments such as softening treatment and flushing were performed to obtain suede-like artificial leather. This artificial leather has excellent napping properties, has a high fluff density, and has a large writing effect.
Furthermore, it was a material that was rich in flexibility, stretchability, and fullness, and was suitable for clothing, especially sports clothing. Moreover, the condition of the internal fibers of this artificial leather was the same as in Examples 8 to 11. <Effects of the Invention> The fiber-entangled nonwoven fabric of the present invention is composed of three-dimensional entanglement of ultrafine fiber bundle fibers and/or modified fibers that have been modified into fibers with micro spaces, has excellent fiber entanglement properties, and is resistant to repeated elongation. It has a wide elongation range that does not substantially cause structural deformation or structural destruction even when deformed, and has a rich and flexible texture that is rich in elongation and is suitable as a base material for artificial leather. It is a nonwoven fabric with entangled fibers. Furthermore, by subjecting the fiber-entangled nonwoven fabric of the present invention to a napping treatment on the surface, a highly elastic artificial leather with a suede-like surface with a high density of ultrafine fiber naps is created, and a film layer of an elastic polymer is added to the surface. By finishing it with a grain layer, highly elastic silver-coated artificial leather can be obtained.

Claims (1)

[Scope of Claims] 1. Ultrafine fiber bundle fibers or fine fibers consisting of short fibers of modified elastic fibers A, which are ultrafine fiber bundle fibers or fibers with micro spaces, and ultrafine fiber bundle fibers or fine fibers, which are made of an elastic polymer A mainly composed of polyurethane elastomer, and an inelastic polymer B. A fiber-entangled nonwoven fabric formed by three-dimensionally entangling short fibers of modified inelastic fibers B, which are fibers having spaces, in which the entangled state of the fibers in the nonwoven fabric is different from that of modified inelastic fibers. B is a fiber entangled nonwoven fabric characterized in that it is formed by bending and bending the modified elastic fibers A in a tense entangled state and entangling them in a loose tissue structure. 2. Ultrafine fiber bundle fibers or fibers with microspaces consisting of short fibers of modified elastic fibers A, which are ultrafine fiber bundle fibers or fibers with microspaces, and inelastic polymer B, which are made of elastic polymer A mainly composed of polyurethane elastomer. It is a fiber-entangled nonwoven fabric formed by mixing modified inelastic fibers B with short fibers and entangling them in three dimensions. A polymer mainly composed of an elastic polymer is contained in the fiber entanglement space of the fiber entangled nonwoven fabric, which is formed by bending and bending the modified elastic fibers A in the state and entangling the loosened tissue structure. Fiber-entangled nonwoven fabric.