JP2006241620A - Nubuck leather like sheet-shaped product and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide nubuck leather like sheet-shaped products excellent in surface smoothness and having densely and finely napped surface, and to provide a method for producing the products. <P>SOLUTION: The nubuck leather like sheet-shaped product comprises a short-fiber nonwoven fabric having 0.0001-0.5 dtex single fiber fineness and 0.300-0.700 g/cm<SP>3</SP>apparent density, has 5-500 μm napping length and is characterized by containing no film-like substance comprising an elastic polymer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a nubuck leather-like sheet-like material excellent in a sense of fulfillment that can be used for shoes, furniture, clothing, and the like, and a method for producing the same. More specifically, the present invention relates to a nubuck-like leather-like sheet-like material that is mainly made of a fiber material, has a sufficient texture, physical properties, and feels worn out, and a method for producing the same.

  A leather-like sheet-like material comprising an ultrafine fiber nonwoven fabric and an elastic polymer has excellent characteristics not found in natural leather, and is widely used in various applications. In particular, the nubuck leather sheet-like material having a writing effect while having a shorter nap length than a suede tone and having an appearance close to a silver surface tone has a higher-class appearance, such as vehicles, furniture, Widely used as surface materials such as bags and office supplies, clothing and bags. In producing such a nubuck leather-like sheet material, the fiber sheet material is impregnated with an elastic polymer solution such as polyurethane, and then the fiber sheet material is immersed in water or an organic solvent aqueous solution to obtain elastic weight. Generally employed is a method in which naps are formed by wet-solidifying the coalescence and then grinding these surfaces.

  However, in the conventional method for producing a leather-like sheet material, that is, a method for raising an ultrafine fiber nonwoven fabric impregnated with a resin such as polyurethane (for example, Patent Document 1), an attempt is made to form a dense raised surface. As a result, the length of the raised hair is inevitably long, and the appearance becomes suede. On the other hand, if the nap length is shortened in order to obtain a nubuck tone, the fiber density is lowered, and there is a problem that the quality of the polyurethane deteriorates due to the exposed polyurethane or the like. That is, in the conventional manufacturing method, it was difficult to obtain a nubuck-like leather-like sheet-like material even if the napped length was simply shortened.

  In addition, for example, a method is disclosed in which a raised fabric having napped fibers made of ultrafine fibers is impregnated or coated with resin to fix the napped hair, and then the napped surface is pressed with a calender roll and then the raised surface is buffed ( For example, Patent Document 2).

  However, even though these methods can improve the smoothness, a short nap length can be formed on the surface, but since the surface layer portion still contains a large amount of resin, the resin is exposed if the nap length is short. However, it is insufficient to obtain uniform and dense napping.

  Further, when the nap on the surface gathers or the nap comes off due to use, there is a problem that the resin is exposed and the surface quality is greatly deteriorated.

  In addition, there is a method in which after raising a fiber base material composed of an ultrafine fiber nonwoven fabric and an elastic polymer foam layer, a raised resin is further applied to the raised surface, followed by raising treatment (for example, Patent Document 3).

Although this method improves surface smoothness, it is still insufficient for dense napping because the surface is a layer in which fibers and resin are mixed.
Japanese Patent Publication No. 48-44849 Japanese Examined Patent Publication No. 62-42076 Japanese Patent Application Laid-Open No. 7-133592

  An object of the present invention is to provide a nubuck-like leather-like sheet-like material having excellent surface smoothness, a dense and fine napped surface, and a method for producing the same. Furthermore, the present invention provides a leather-like sheet-like material having no rubber-like texture, excellent recyclability, yellowing resistance, and the like, and a method for producing the same.

In order to solve the above problems, the present invention has the following configuration. That is, the nubuck leather-like sheet-like material of the present invention is composed of a short fiber nonwoven fabric having a single fiber fineness of 0.0001 to 0.5 dtex and an apparent density of 0.300 to 0.700 g / cm ³ , and a napped length of 1 to It is 500 μm and there is no film-like material made of an elastic polymer.

  Moreover, the manufacturing method of the leather-like sheet-like material of the present invention is to manufacture a composite short fiber nonwoven fabric by a needle punch method using a composite short fiber of 1 to 10 dtex capable of generating ultrafine fibers of 0.0001 to 0.5 dtex. Then, after performing high-speed fluid treatment at a pressure of at least 10 MPa, raising treatment is performed, and then press treatment is performed.

  According to the present invention, it is possible to provide a nubuck-like leather-like sheet-like material that has excellent surface smoothness, has a fine and fine napped surface, and can greatly reduce the amount of polyurethane used.

  Furthermore, according to this invention, the leather-like sheet-like material excellent in the fullness which can be used for a bag, shoes, furniture, clothing, interior materials, etc. can be obtained.

  The nubuck-like leather-like sheet-like material referred to in the present invention is the distance from the base material to the fiber tip when the fiber is raised, among the raised-like leather-like sheet-like material called suede, velor, nubuck-like , Written as napped length).

  The nap length of the nubuck leather-like sheet material in the present invention is preferably 1 μm or more, more preferably 10 μm or more, and further preferably 30 μm or more. If it is less than 1 μm, the lighting effect does not appear clearly, and it is difficult to obtain an elegant appearance. The upper limit is preferably 500 μm or less, more preferably 300 μm or less, and even more preferably 200 μm or less. When it exceeds 500 μm, it is difficult to obtain a nubuck-like appearance.

  Conventionally, a leather-like sheet was generally produced by impregnating a nonwoven structure with an appropriate amount of an elastic polymer such as polyurethane, but in the present invention, a particularly dense napped surface is formed. Therefore, it is preferable that the nonwoven fabric structure is substantially free of an elastic polymer such as polyurethane and is substantially made of a fiber material. Here, “consisting essentially of a fiber material” means that it consists only of a fiber material of a general leather-like sheet-like material and a fiber material of an elastic polymer, but post-processing In the leather-like sheet material of the present invention, other processing agents used in the present invention, for example, dyes, softeners, abrasion resistance improvers, various fastness improvers, antistatic agents or fine particles may be contained.

  In the present invention, even when an elastic polymer such as polyurethane is impregnated into the nonwoven fabric structure, the amount is preferably 10% by weight or less, more preferably 5% by weight or less, and 3% by weight. More preferably, it is% or less. When a large amount of an elastic polymer is contained, if the nap length is finished short to obtain a nubuck tone, a large amount of the elastic polymer is exposed on the surface, and the quality is greatly lowered. In addition, the nap on the fiber surface is fixed, and the appearance tends to be inferior. By being substantially made of a fiber material, the elastic polymer is not exposed even by use, and the appearance change can be suppressed.

  Here, in the nubuck leather-like sheet-like product of the present invention, it is necessary that a film-like product made of an elastic polymer does not exist. The absence of the elastic polymer film increases the napped density on the surface and makes napping easier to disperse, improving the nap density on the surface. The presence of the elastic polymer film can be confirmed by taking a cross-sectional photograph taken with an electron scanning microscope in the state where the nap is laid and observing the photograph.

  The film-like material referred to here is one in which an elastic polymer is continuously observed at least 10 μm or more in the fiber gap when a cross section is observed with an electron scanning microscope, and is obtained by, for example, wet coagulation of polyurethane. Like a microporous shape, it is found in conventional artificial leather. Therefore, for example, it may be present in the form of a film on the fiber surface or attached in the form of particles. Due to the presence of this film-like material on the surface layer, in the nubuck leather-like sheet-like material having a short nap length, the elastic polymer is likely to be exposed on the surface, and it is difficult to obtain the fineness of napping. As a means for suppressing the film-like structure, a method using a water-dispersed elastic polymer can be preferably adopted in addition to a method for suppressing the amount of the elastic polymer applied.

Moreover, the leather-like sheet of this invention preferably has a basis weight is 100 to 600 / ^{m 2,} more preferably from 120~450g / ^{m 2,} still to be 140~350g / ^{m 2} preferable. If it is less than 100 g / m ² , the physical properties of the nonwoven fabric structure alone are lowered, and when the woven fabric and / or the knitted fabric are laminated, the appearance of the woven fabric and / or the knitted fabric is easily visible on the surface and the quality is lowered. Therefore, it is not preferable. On the other hand, if it exceeds 600 g / m ² , the wear resistance tends to decrease, such being undesirable. The apparent density is 0.300 to 0.700 g / cm ³ . Apparent density is preferably 0.320~0.600g / cm ^3, further preferably 0.350~0.500g / cm ^3. If it is less than 0.300 g / cm ³ , it becomes difficult to obtain a sufficient surface smoothness and a dense napped surface as a nubuck tone. On the other hand, if it exceeds 0.700 g / cm ³ , a paper-like texture is obtained, which is not preferable.

  The apparent density was determined by measuring the basis weight according to JIS L1096 8.4.2 (1999), then measuring the thickness, and taking the average value of the apparent density obtained therefrom. The thickness was measured using a dial thickness gauge (manufactured by Ozaki Mfg. Co., Ltd., trade name “Peacock H”), 10 samples were measured, and the average value was used.

  In addition, the nubuck leather-like sheet-like product of the present invention is 20000 in an abrasion resistance test measured according to JIS L 1096 (1999) 8.17.5 E method (Martindale method) furniture load (12 kPa). The abrasion loss of the test cloth after wearing the number of times is 20 mg or less, preferably 15 mg or less, more preferably 10 mg or less, and preferably 5 or less, more preferably 3 or less, and even more preferably It is good that it is 1 or less. When the wear loss exceeds 20 mg, fluff tends to adhere to clothes and the like in actual use, which is not preferable. On the other hand, the lower limit is not particularly limited, and the leather-like sheet of the present invention can be obtained with almost no wear loss. In addition, when the number of generated pills exceeds 5, the quality is deteriorated due to a change in appearance when used, which is not preferable.

  In order to obtain such wear resistance, the apparent density is particularly important, and the higher the density, the better. In addition, when fine particles are added, it can be greatly improved, and conversely, when a large amount of a softening agent is used, a tendency to decrease is observed. Therefore, it is necessary to set these conditions while balancing the texture.

    The fiber constituting the nonwoven fabric of the nubuck-like leather-like sheet of the present invention has a single fiber fineness of 0.0001 to 0.5 dtex. The single fiber fineness is preferably 0.001 to 0.3 dtex, more preferably 0.005 to 0.15 dtex. If it is less than 0.0001 dtex, the strength decreases, which is not preferable. On the other hand, if it exceeds 0.5 dtex, the texture becomes hard, and problems such as insufficient entanglement and deterioration of surface quality occur, which is not preferable. However, fibers having a fineness exceeding the above range may be included as long as the effects of the present invention are not impaired.

  The so-called ultrafine fiber manufacturing method in which the single fiber fineness is in the above-mentioned range is not particularly limited. For example, a method of directly spinning ultrafine fibers, a fiber having normal fineness and capable of generating ultrafine fibers (ultrafine fibers) There is a method in which a generation type fiber) is spun and then an ultrafine fiber is generated. And, as a method of using the ultrafine fiber generation type fiber, for example, the sea island type composite fiber is spun and then the sea component is removed, and the split type composite fiber is spun and then divided and made into ultrafine. can do. Among these, in the present invention, it is preferable that the ultrafine fiber can be obtained easily and stably, and it is preferably produced by a sea-island type composite fiber or a split type composite fiber, and further, the same kind that can be dyed with the same kind of dye. It is more preferable to manufacture with a sea-island type composite fiber in that an ultrafine fiber made of a polymer can be easily obtained.

  The sea-island type composite fiber as used in the present invention refers to a fiber in which two or more components are combined and mixed at an arbitrary stage to form a sea-island state, and the method for obtaining this fiber is not particularly limited. ) A method of blending and spinning two or more components in a chip state, (2) A method of kneading a polymer of two or more components in advance to form a chip and then spinning, (3) A polymer of two or more components in a molten state For example, a method of mixing with a stationary kneader in a pack of a spinning machine, and (4) a method of producing using a die such as JP-B Nos. 44-18369 and 54-116417. In the present invention, any method can be used to satisfactorily produce, but the method (4) is preferably employed because the selection of the polymer is easy.

  In the method (4), the cross-sectional shape of the island fiber obtained by removing the sea-island type composite fiber and the sea component is not particularly limited, and for example, round, polygonal, Y, H, X, W, C, π type, etc. Is mentioned. Further, the number of polymer species to be used is not particularly limited, but it is preferably 2 to 3 components in consideration of spinning stability and dyeability, and particularly composed of 2 components of sea 1 component and island 1 component. It is preferable. The component ratio at this time is preferably 0.30 to 0.99, more preferably 0.40 to 0.97 in terms of weight ratio of island fibers to sea-island composite fibers, and 0.50 to 0.80. Is more preferable. If it is less than 0.30, the removal rate of sea components increases, which is not preferable in terms of cost. On the other hand, if it exceeds 0.99, the island components are likely to merge with each other, which is not preferable in terms of spinning stability.

  The polymer to be used is not particularly limited, but the polymer constituting the island component does not include a fiber made of an elastic polymer such as so-called spandex, and has a sense of fulfillment that it is a fiber made of an inelastic polymer. It is preferable because a texture can be obtained. The non-elastic polymer fiber means a polymer excluding a fiber excellent in rubber-like elasticity, such as a polyether ester fiber or a polyurethane fiber such as so-called spandex. Specific examples include fibers made of polyester, polyamide, polypropylene, polyethylene and the like. By being made of a substantially non-elastic polymer fiber material, it is possible to achieve a texture with a sense of fullness without rubber feeling. Among these, polyester fibers, polyamide fibers, or mixed fibers thereof are preferable from the viewpoint of cost and manufacturability. Furthermore, various effects such as easy recyclability, high color developability, high light resistance, yellowing resistance, and the like can be achieved. In particular, in order to facilitate chemical recycling, the fiber material is preferably made of polyethylene terephthalate or nylon 6.

  The polyester that can be used in the present invention is a polymer that is synthesized from a dicarboxylic acid or an ester-forming derivative thereof and a diol or an ester-forming derivative thereof, and is particularly limited as long as it can be used as a composite fiber. Is not to be done. Specifically, for example, polyethylene terephthalate, polytrimethylene terephthalate, polytetramethylene terephthalate, polycyclohexylene dimethylene terephthalate, polyethylene-2,6-naphthalenedicarboxylate, polyethylene-1,2-bis (2- Chlorophenoxy) ethane-4,4′-dicarboxylate, polylactic acid and the like. In the present invention, the most commonly used polyethylene terephthalate or a polyester copolymer mainly containing ethylene terephthalate units is preferably used.

  The polyamide that can be used in the present invention is not particularly limited as long as it can be used as a composite fiber. For example, it has an amide bond such as nylon 6, nylon 66, nylon 610, and nylon 12. Mention may be made of polymers.

  On the other hand, the polymer used as the sea component of the sea-island composite fiber is not particularly limited as long as it has chemical properties that are higher in solubility and decomposability than the polymer constituting the island component. Depending on the selection of the polymer constituting the island component, for example, polyolefins such as polyethylene and polystyrene, 5-sodium sulfoisophthalic acid, polyethylene glycol, sodium dodecylbenzene sulfonate, bisphenol A compound, isophthalic acid, adipic acid, dodecadioic acid Polyester obtained by copolymerizing cyclohexyl carboxylic acid or the like can be used. Polystyrene is preferable from the viewpoint of spinning stability, but a copolymer polyester having a sulfone group is preferable because it can be easily removed without using an organic solvent. The copolymerization ratio is preferably 5 mol% or more from the viewpoint of processing speed and stability, and 20 mol% or less from the viewpoint of ease of polymerization, spinning and stretching. A preferred combination in the present invention is a copolymer polyester using polyester or polyamide as the island component, or both, and having a polystyrene or sulfone group as the sea component.

  To these polymers, inorganic particles such as titanium oxide particles may be added to the polymer in order to improve the concealing property. In addition, lubricants, pigments, heat stabilizers, ultraviolet absorbers, conductive agents, heat storages, etc. Materials, antibacterial agents, etc. can be added according to various purposes.

  Further, the method for obtaining the sea-island type composite fiber is not particularly limited. For example, after taking the undrawn yarn using the die shown in the above method (4), the wet-heat or dry heat, or both of them are 1 to 3 It can be obtained by step stretching.

  In addition, when using split type composite fiber, it can mainly carry out according to the manufacturing method of the above-mentioned sea-island type composite fiber by compounding two or more components in the die.

  As a kind of the nonwoven fabric in this invention, it is required that it is a short fiber nonwoven fabric at the point which is excellent in the quality and the texture. Therefore, it is necessary to cut the above-mentioned fiber to an appropriate length, and it is preferably 10 cm or less, more preferably 7 cm or less in consideration of productivity and the texture of the obtained product. Those having a fiber length exceeding 10 cm may be included as long as the effects of the present invention are not impaired. Further, the lower limit is not particularly limited and can be appropriately set depending on the production method of the nonwoven fabric. However, if it is less than 0.1 cm, dropout tends to increase, and properties such as strength and wear resistance tend to decrease. It is preferable that And it is preferable that these short fibers are intertwined with each other from the viewpoint of obtaining an excellent sense of fullness and strength. In view of physical properties such as strength and quality, it is preferable that the fiber lengths of the respective short fibers are not uniform. That is, it is preferable that a short short fiber and a long short fiber are mixed in a fiber length of 0.1 to 10 cm. For example, a nonwoven fabric in which short fibers of 0.1 to 1 cm, preferably 0.1 to 0.5 cm, and short fibers of 1 to 10 cm, preferably 2 to 7 cm are mixed can be exemplified. In such a nonwoven fabric, for example, short fiber length fibers contribute to improvement of surface quality, densification, and the like, and long fiber length fibers contribute to obtaining high physical properties.

  The method of mixing fibers having different fiber lengths is not particularly limited. The method of using sea-island type composite fibers having different island fiber lengths, the method of mixing short fibers having various fiber lengths, and the nonwoven fabric to the fiber length. The method of giving a change etc. are mentioned. In the present invention, a nonwoven fabric in which fiber lengths are mixed easily can be obtained particularly easily, and a fiber length suitable for two types of entanglement means described later can be generated at each stage. Then, a method of changing the fiber length is preferably employed. For example, by a method of splitting into two or more pieces perpendicular to the thickness direction of the nonwoven fabric (split processing), even if the single fiber length is before the split processing, nonwoven fabrics having various fiber lengths after the split processing It can be manufactured easily. The split treatment here is a treatment similar to the division step in general natural leather, and is preferably performed before the high-speed fluid treatment described later. Specifically, it can be performed by a rice cracker manufactured by Murota Manufacturing Co., Ltd.

  The method preferably used as a method for producing the nubuck leather-like sheet-like material of the present invention is a method combining the needle punch method and the high-speed fluid treatment. Thereby, even if a small amount of an elastic polymer is imparted or the elastic polymer is not substantially contained, sufficient physical properties can be easily obtained. Here, at the time of needle punching, a non-woven fabric having a fiber length of 1 to 10 cm, preferably 3 to 7 cm, and then splitting into two or more pieces perpendicular to the thickness direction to generate short fibers. Then, by performing high-speed fluid treatment, a nubuck leather-like sheet-like material having excellent physical properties and having a dense fiber layer on the surface layer can be easily obtained.

  As a method for forming a short fiber into a non-woven fabric, a dry method in which a web is obtained using a card, a cross wrapper, a random weber, or a wet method such as a papermaking method can be employed. A dry method that can easily combine two entanglement methods of fluid treatment is preferable. In the entanglement treatment, it is possible to integrate with other woven fabrics, knitted fabrics, and nonwoven fabrics in order to impart an appropriate elongation or elongation stop, or to improve physical properties such as strength of the nonwoven fabric obtained.

In the needle punching treatment, the apparent fiber density is preferably 0.120 to 0.300 g / cm ³ , more preferably 0.150 to 0.250 g / cm ³ . If it is less than 0.120 g / cm ³ , the entanglement will be insufficient and the desired physical properties will be difficult to obtain. The upper limit is not particularly defined, but if it exceeds 0.300 g / cm ³ , problems such as breakage of the needle needle and remaining of the needle hole are not preferable.

  Moreover, when performing a needle punch process, it is preferable that the single fiber fineness of a composite fiber is 1-10 dtex, 2-8 dtex is more preferable, and 2-6 dtex is further more preferable. When the single fiber fineness is less than 1 dtex or exceeds 10 dtex, the entanglement by the needle punch becomes insufficient, and it becomes difficult to obtain good physical properties and uniformity.

The needle punching treatment in the present invention is not a role as a temporary fixing for obtaining simple process passability, but it is preferable to sufficiently entangle the fibers. Therefore, the driving density is preferably 100 / cm ² or more, more preferably 500 / cm ² or more, and still more preferably 1000 / cm ² or more.

  The composite short fiber nonwoven fabric thus obtained is preferably shrunk by dry heat and / or wet heat, and further densified.

  Next, the composite short fiber nonwoven fabric is subjected to high-speed fluid treatment at a pressure of at least 10 MPa to entangle the ultrafine fibers. Here, it is preferable to perform the ultrafine processing before performing the high-speed fluid processing, at the same time as the high-speed fluid processing, or at the same time as before the high-speed fluid processing. Although it is possible to make the composite short fiber ultrafine by high-speed fluid treatment, even in that case, after the composite short fiber is made ultrafine, the high-speed fluid treatment is performed to sufficiently entangle the ultrafine fibers. It is preferable to carry out. If the high-speed fluid treatment after ultrafine processing is insufficient, it is difficult to obtain the nubuck-like leather-like sheet-like material of the present invention.

  The ultrafine treatment method is not particularly limited, and examples thereof include a mechanical method and a chemical method. The mechanical method is a method of miniaturization by applying a physical stimulus, for example, a method of applying pressure between rollers in addition to the method of giving an impact such as the needle punch method or the water jet punch method described above, Examples include a method of performing ultrasonic treatment. The chemical method includes, for example, a method in which at least one component constituting the composite fiber is subjected to changes such as swelling, decomposition, and dissolution by a drug. In the present invention, it is preferable to make the fiber finer by a chemical method because it can be made sufficiently finer, and in particular, a composite short fiber nonwoven fabric is produced with an ultrafine fiber-generating fiber using an alkali-degradable sea component. Then, the method of treating with a neutral to alkaline aqueous solution and making it ultrafine by a chemical method is one of the preferred embodiments of the present invention because it is preferable in working environment without using a solvent. The neutral to alkaline aqueous solution here is an aqueous solution having a pH of 6 to 14, and the chemicals used are not particularly limited. For example, an aqueous solution containing organic or inorganic salts may be used as long as it exhibits a pH in the above range, and alkali metal salts such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, sodium bicarbonate, calcium hydroxide, water Examples include alkaline earth metal salts such as magnesium oxide. Further, if necessary, amines such as triethanolamine, diethanolamine, monoethanolamine, a weight loss accelerator, a carrier, and the like can be used in combination. Of these, sodium hydroxide is preferable in terms of price and ease of handling. Furthermore, it is preferable that the sheet is subjected to the neutral to alkaline aqueous solution treatment described above, and then neutralized and washed as necessary to remove the remaining chemicals and decomposition products, and then dried.

  As a method of simultaneously performing these ultrafine processing and high-speed fluid processing, for example, using a composite fiber composed of a water-soluble sea component, removing and entanglement by water jet punch, two or more components having different alkali decomposition rates Examples include a method in which a composite fiber is used to decompose an easily soluble component through an alkali treatment liquid and then subjected to final removal and entanglement treatment by a water jet punch. In addition, there is also a method of splitting with a water jet punch using a split type composite fiber, and after ultrathinning at least almost completely as described above, the ultrafine fibers are entangled with each other by the water jet punch. It is important to adopt the form.

  As the high-speed fluid processing, it is preferable to perform water jet punch processing using a water flow in terms of the working environment. At this time, it is preferable to perform the water in a columnar flow state. In order to obtain a columnar flow, it is usually obtained by ejecting from a nozzle having a diameter of 0.06 to 1.0 mm at a pressure of 1 to 60 MPa. In order to obtain efficient entanglement and good surface quality, this treatment preferably has a nozzle diameter of 0.06 to 0.15 mm and an interval of 5 mm or less, and a diameter of 0.06 to 0.12 mm. The interval is more preferably 1 mm or less. These nozzle specifications do not need to be all the same when processing multiple times. For example, a nozzle having a large hole diameter and a small hole diameter can be used in combination, but the nozzle having the above configuration is used at least once. It is preferable. In particular, when the diameter exceeds 0.15 mm, the entanglement property between the ultrafine fibers decreases, the surface becomes easy to peach, and the surface smoothness also decreases. Accordingly, a smaller nozzle hole diameter is preferable, but if it is less than 0.06 mm, nozzle clogging is likely to occur. Further, for the purpose of achieving uniform entanglement in the thickness direction and / or improving the smoothness of the nonwoven fabric surface, the treatment is preferably repeated a number of times. Further, the water flow pressure is appropriately selected according to the basis weight of the nonwoven fabric to be treated, and the higher the basis weight, the higher the pressure. Furthermore, in order to highly entangle the ultrafine fibers, it is preferable to treat at least once with a pressure of 10 MPa or more, and more preferably 15 MPa or more. Further, the upper limit is not particularly limited, but the cost increases as the pressure increases, and if the basis weight is low, the nonwoven fabric may be non-uniform or fluff may be generated due to fiber cutting. Yes, more preferably 30 MPa or less. By doing so, for example, in the case of ultrafine fibers obtained from composite fibers, it is common that the ultrafine fiber bundles in which the fibers are concentrated are mainly intertwined. It is possible to obtain an ultra-fine short fiber nonwoven fabric in which ultra-fine fibers are highly entangled to such an extent that they are hardly observed, thereby improving surface characteristics such as wear resistance. Note that a water immersion process may be performed before the water jet punch process. Furthermore, in order to improve the surface quality, it is also possible to move the nozzle head and the nonwoven fabric relatively, or to insert a wire mesh between the nonwoven fabric and the nozzle after the entanglement to perform watering treatment. Further, before performing the high-speed fluid processing, it is preferable to perform split processing on two or more sheets perpendicular to the thickness direction. In this way, the ultrafine fibers are preferably entangled until the 10% modulus in the vertical direction is 8 N / cm or more, more preferably 10 N / cm or more.

  In addition, in the nubuck leather-like sheet-like material of the present invention, other woven fabrics and knitted fabrics are used for imparting appropriate elongation or elongation stop, or for improving physical properties such as strength, functions such as stretch properties and drape properties. It is preferable to integrate with the nonwoven fabric. The woven fabric structure is not particularly limited, and for example, plain weave, oblique weave, satin weave, leash weave, etc. can be adopted, but plain weave is preferred in terms of cost. The knitting structure is not particularly limited, and for example, warp knitting, weft knitting, or the like can be employed. As the fiber used in this case, a fiber having the same or similar dyeing property as the fiber constituting the nonwoven fabric is preferable in that the complexity of the dyeing process can be suppressed.

  In addition, as a method for integrating these woven fabrics or knitted fabrics, they can be entangled and integrated by high-speed fluid treatment instead of adhesive bonding because they can suppress the hardening of the texture and can select a wide range of types of woven fabrics or knitted fabrics. Is preferred. On the other hand, when entangled and integrated by the needle punch method, it is preferable to apply a twist of about 1000 to 3000 T / m in order to prevent damage to the fibers constituting the woven or knitted fabric by the needle.

  In addition, as a means for laminating the nonwoven fabric and the woven fabric or the knitted fabric, for example, a method of making a paper-making slurry of the ultra fine fiber on the woven fabric or the knitted fabric, the ultra fine fiber generating fiber and the woven fabric or the knitted fabric are entangled and integrated, and then the ultra fine fiber There is no particular limitation, and a method for producing a fiber, a method for producing an ultrafine fiber nonwoven fabric, and a method for entwining a woven fabric or a knitted fabric can be employed. However, in terms of being able to obtain a high-quality surface, a method in which an ultrafine fiber nonwoven fabric is once manufactured and then entangled with a woven fabric or a knitted fabric is preferable. At this time, the woven fabric or the knitted fabric may be disposed on one side or between the nonwoven fabrics, and is not particularly limited.

  Next, it is preferable to dye the obtained nonwoven fabric. The method for dyeing is not particularly limited, and the dyeing machine used may be any of a liquid dyeing machine, a thermosol dyeing machine, a high-pressure jigger dyeing machine, etc., but the texture of the resulting leather-like sheet is excellent. It is preferable to dye using a liquid dyeing machine.

  In addition, after performing high-speed fluid treatment, an elastic polymer can be applied for the purpose of improving wear resistance or obtaining a more uniform surface before or after dyeing. The amount of the elastic polymer applied is preferably 10% by weight or less, more preferably 5% by weight or less, and further preferably 3% by weight or less. Furthermore, according to the method for producing a nubuck leather-like sheet-like material of the present invention, it is possible to make it substantially free of an elastic polymer and mainly consist of a fiber material, which is a preferred embodiment.

  As the elastic polymer, it is preferable to select and use various materials that can appropriately obtain the desired texture, physical properties, and quality. For example, polyurethane, acrylic, styrene-butadiene, and the like are preferably used. Among these, it is preferable to use polyurethane in terms of flexibility, strength, quality, and the like. The method for producing polyurethane is not particularly limited, and can be produced by appropriately reacting a conventionally known method, that is, polymer polyol, diisocyanate, and chain extender. When an elastic polymer is contained in the nonwoven fabric structure, it is preferable to use a water-dispersed elastic polymer in order to prevent the elastic polymer from forming a film structure. This water-dispersed elastic polymer may be a self-emulsifying type or a forced emulsifying type. By using a water-dispersed elastic polymer, it becomes difficult to form a film-like material, and it is preferable to adopt dry heat coagulation as a coagulation method rather than wet coagulation using hot water or steam that is usually performed. . The application amount of the water-dispersed elastic polymer is preferably 0.1 to 10% by weight.

  Further, it is preferable that fine particles are contained in the fiber material constituting the leather-like sheet-like material in terms of excellent wear resistance. In particular, when the ultrafine fibers of the fiber material are intertwined with each other, a large wear resistance improvement effect can be obtained by the presence of fine particles. This also makes it possible to obtain a squeaky or dry texture.

  The material of the fine particles here is not particularly limited as long as it is insoluble in water, and examples thereof include inorganic substances such as silica, titanium oxide, aluminum and mica, and organic substances such as melamine resin. The average particle diameter of the fine particles is preferably 0.001 to 30 μm, more preferably 0.01 to 20 μm, and still more preferably 0.05 to 10 μm. When the thickness is less than 0.001 μm, it is difficult to obtain the expected effect, and when it exceeds 30 μm, the washing durability decreases due to dropping off from the fiber. The average particle diameter can be measured using a measurement method suitable for the material and size, for example, the BET method, the laser method, and the Coulter method.

  The amount of these fine particles can be appropriately adjusted within a range in which the effect of the present invention can be exhibited, but is preferably 0.01 to 10% by weight, more preferably 0.02 to 5% by weight, and still more preferably. Is 0.05 to 1% by weight. If it is 0.01 weight% or more, the improvement effect of abrasion resistance can be exhibited notably, and the effect tends to become large, so that the amount is increased. However, if it exceeds 10% by weight, the texture becomes hard, which is not preferable. In order to prevent fine particles from falling off and improve durability, it is preferable to use a small amount of resin in combination.

  The means for applying the fine particles is not particularly limited and can be appropriately selected from a pad method, a method using a liquid dyeing machine and a jigger dyeing machine, and a spraying method.

  Further, in order to obtain a soft texture and a smooth surface touch, the leather-like sheet of the present invention preferably contains a softening agent. It does not specifically limit as a softening agent, What is generally used for a textile fabric or a knitted fabric is suitably selected according to a fiber type. For example, in the 23rd edition of Dyeing Note (Issue Color Co., Ltd., issued on August 31, 2002), those described under the names of texture finish and soft finish can be appropriately selected. Among these, a silicone emulsion is preferable in terms of excellent flexibility effect, and an amino-modified or epoxy-modified silicone emulsion is more preferable. When these softeners are included, the wear resistance tends to decrease. Therefore, the amount of the softener and the amount of the fine particles can be appropriately adjusted while balancing the target texture and the wear resistance. preferable. Therefore, the amount is not particularly limited, but if it is too small, the effect cannot be exhibited, and if it is too large, there is a feeling of stickiness, so a range of 0.01 to 10% by weight is preferable.

  The means for applying the softening agent is not particularly limited, and a pad dye method, a method using a liquid dyeing machine or a jigger dyeing machine, a spraying method, or the like can be used. From the viewpoint of production cost, it is preferable to apply the fine particles simultaneously with the fine particles.

  The fine particles and softening agent are preferably applied after dyeing. If applied before dyeing, the effect may be reduced due to omission during dyeing or uneven dyeing may occur, which is not preferable. Moreover, since the nonwoven fabric containing microparticles | fine-particles tends to be hard to raise, it is preferable to provide microparticles | fine-particles after raising.

  Further, the nubuck leather-like sheet-like product of the present invention preferably has a dense fiber layer at least near the surface layer. Thereby, it is possible to obtain a better surface appearance. The dense fiber layer as used herein refers to a portion in which fibers are uniformly and densely present in a layer shape perpendicular to the thickness direction in cross-sectional observation with an electron scanning microscope, and the fiber occupies a larger proportion than an elastic polymer. It shows that. The entire sheet may have a dense fiber structure.

  In order to form such a dense fiber layer and to obtain good smoothness, dense napped length, high wear resistance, etc., the fine fibers are entangled with each other by high-speed fluid treatment, and a calendar, etc. Therefore, it is preferable to perform a press process. In the case where an elastic polymer is included in the nonwoven fabric structure, it is possible to uniformly penetrate the elastic polymer when impregnating the elastic polymer by performing a pressing treatment after applying the elastic polymer to the nonwoven fabric structure. Is preferable. Even when a water-dispersed elastic polymer is used, it is preferable to perform a press treatment after the water-dispersed elastic polymer is applied.

  The temperature of the press treatment is preferably 100 ° C. or higher, more preferably 120 ° C. or higher, and further preferably 130 ° C. or higher for the purpose of obtaining a smoother flat surface. Moreover, in order to suppress the fall of color developability and fastness, 200 degrees C or less is preferable, 180 degrees C or less is more preferable, and 160 degrees C or less is further more preferable. On the other hand, the compression ratio is appropriately adjusted depending on the density before compression, but is preferably 0.1 times or more, more preferably 0.3 times or more, and more preferably 0.5 times or more in order to suppress the curing of the texture. preferable. Further, for the purpose of improving the smoothness and the denseness of napping, 0.8 times or less is preferable, 0.7 times or less is more preferable, and 0.6 times or less is more preferable. Further, the linear pressure at this time is not particularly limited, but can be appropriately adjusted within a range of, for example, 5 to 6000 N / cm. Moreover, a processing speed is not specifically limited, For example, it can adjust suitably in the range of 0.1-50 m / min.

  If such press treatment is performed before the high-speed fluid treatment, the entanglement due to the high-speed fluid treatment is difficult to proceed. Therefore, it may be performed at any stage of the production process as long as the high-pressure fluid treatment is performed. However, in the present invention, the nubuck-like appearance with a short nap length can be obtained by performing the napping treatment. It is preferable because it is easy. Moreover, in order to maintain the smoothness in the final product, it is preferable to perform it before or after dyeing, or both before and after dyeing.

  In order to form napped hair, it is preferable to perform raising treatment with sandpaper or a brush. Such napping treatment may be performed once or a plurality of times in any step as long as it is after the high-speed fluid treatment. However, in order to uniformly form a short raised length, it is preferably performed at least before the press treatment. At this time, raising by sandpaper using a belt dancer or a roller sander can be preferably applied. However, the sandpaper having a grain size of # 400 to 1000 has a smoother surface, shorter hair, and more uniform. Since napping can be formed, it is preferable.

Hereinafter, the present invention will be described in more detail with reference to examples. In addition, the physical-property value in an Example was measured by the method described below.
(1) Weight per unit area, apparent density Per unit area was measured by the method of JIS L 1096 8.4.2 (1999). Further, the thickness was measured with a dial thickness gauge (manufactured by Ozaki Mfg. Co., Ltd., trade name “Peacock H”), and the apparent fiber density was calculated from the basis weight value.
(2) Martindale abrasion test JIS L 1096 (1999) 8.17.5 After abrasion of 20000 times in the abrasion resistance test measured according to E method (Martindale method) furniture load (12 kPa) The weight loss of the test cloth was evaluated, and the number of pills was counted from the appearance.
(3) Napping length Randomly sampled at five locations, took a cross-sectional photograph with an electronic scanning microscope with the napping of the surface raised by hand, and the top of napping and the entangled surface excluding pilling and loose fibers The vertical distance (height from the entangled surface) was determined, and the average value was defined as the napped length.

Example 1
A web was prepared through a card and a cross wrapper using a sea-island type composite short fiber having a single fiber fineness of 3 dtex, 36 islands, and a fiber length of 51 mm consisting of 45 parts of polystyrene as a sea component and 55 parts of polyethylene terephthalate as an island component. Subsequently, it was processed with a 1 barb type needle punch at a driving density of 2000 pieces / cm ² to obtain a composite short fiber nonwoven fabric with an apparent fiber density of 0.212 g / cm ³ . Next, it is immersed in an aqueous solution of polyvinyl alcohol (PVA) 12% having a polymerization degree of 500 and a saponification degree of 88% heated to about 95 ° C. so as to have an adhesion amount of 25% with respect to the nonwoven fabric weight in terms of solid content. Simultaneously with the impregnation with PVA, a shrinkage treatment was carried out for 2 minutes, followed by drying at 100 ° C. to remove moisture. The obtained sheet was treated with trichrene at about 30 ° C. until the polystyrene was completely removed, and ultrafine fibers having a single fiber fineness of about 0.046 dtex were obtained. Next, using a standard splitting machine manufactured by Murota Manufacturing Co., Ltd., after splitting into two pieces perpendicular to the thickness direction, polyethylene terephthalates having intrinsic viscosities of 0.40 and 0.75 were combined by weight. A plain fabric after a relaxation treatment with a weaving density of 250 × 120 yarns / inch, made of a composite fiber of 1300 T / m, 110 dtex 24 filaments bonded side by side at 50:50, is stacked with a pore diameter of 0.1 mm. , Treated with water jet punch consisting of nozzle heads with a spacing of 0.6 mm at 10 mpa and 20 mpa on both front and back at a processing speed of 1 m / min, entangled with removal of PVA to obtain an ultrafine short fiber nonwoven fabric (A) It was.

  Next, after brushing with # 600 mesh sandpaper, the steel calender heated to 150 ° C. was used to set the compression ratio to 0.5 times and press processing was performed at a speed of 0.5 m / min. Next, it dye | stained at 120 degreeC and 45 minutes by the density | concentration of 20% owf using Sumikaron Blue S-BBL200 (made by Sumika Chemtex Co., Ltd.) with the liquid flow dyeing machine. Thereafter, softening agent (amino-modified silicone emulsion “Silicollan AN-2200” manufactured by One Co., Ltd.) and fine particles (colloidal silica “Snowtex 20L” manufactured by Nissan Chemical Industries, Ltd., average particle size 0.04 to 0.05 μm: BET And then squeezed so that the colloidal silica is 0.1% by weight, and then dried at 100 ° C.

The nubuck-like leather-like sheet thus obtained had a basis weight of 259 g / cm ² and an apparent density of 0.400 g / cm ³ . In addition, the entire sheet forms a dense fiber structure, no polyurethane film is observed, and the surface has dense napped (napped length 200 μm). As a result of the abrasion resistance test, One excellent result was obtained with 10 mg weight loss.

Example 2
After obtaining the ultrafine fiber nonwoven fabric (A) in the same manner as in Example 1, it was brushed with # 600 mesh sandpaper, and then an emulsion polyurethane (“Evaphanol APC-55” manufactured by Nikka Chemical Co., Ltd.) was used. After impregnation to give a solid content of 5%, heat treatment was performed at 150 ° C. for 10 minutes. Next, using a liquid calender, Sumikaron Blue S-BBL200 (manufactured by Sumika Chemtex Co., Ltd.) was dyed at a concentration of 20% owf at 120 ° C. for 45 minutes and heated at 150 ° C. The compression rate was set to 0.5 times, and press treatment was performed at a speed of 0.5 m / min. Subsequently, the softening agent and fine particles were applied in the same manner as in Example 1.

The nubuck-like leather-like sheet thus obtained had a basis weight of 275 g / cm ² and an apparent density of 0.500 g / cm ³ . In addition, the entire sheet forms a dense fiber structure, and no polyurethane film is observed, and a small amount of napped (napped length 50 μm) is formed on the surface. Excellent results were obtained with 2 mg weight loss.

Example 3
The treatment was performed in the same manner as in Example 2 except that no emulsion polyurethane was applied. The nubuck-like leather-like sheet thus obtained had a basis weight of 264 g / cm ² and an apparent density of 0.447 g / cm ³ . In addition, the entire sheet forms a dense fiber structure, no polyurethane film is observed, and a small amount of napped (napped length of 300 μm) is formed on the surface. Excellent results were obtained with 2 pieces and a weight loss of 5 mg.

Comparative Example 1
A web was prepared through a card and a cross wrapper using a sea-island type composite fiber having a single fiber fineness of 3 dtex, 36 islands, and a fiber length of 51 mm consisting of 45 parts of polystyrene as a sea component and 55 parts of polyethylene terephthalate as an island component. Subsequently, it processed with 1500 bar / cm < ² > implantation density with a 1 barb type needle punch, and obtained the composite short fiber nonwoven fabric of fiber apparent density 0.210 g / cm < ³ >. Next, it is immersed in a 12% aqueous solution of PVA heated to about 95 ° C. so that the amount of adhesion is 25% with respect to the weight of the nonwoven fabric in terms of solid content. And dried to remove moisture. The obtained sheet was treated with trichrene at about 30 ° C. until the polystyrene was completely removed.

  In addition, as a polymer diol, a 50:50 mixture of 2000 molecular weight polyhexamethylene carbonate diol and 2000 molecular weight polytrimethylene glycol, 4,4′-diphenylmethanediamine isocyanate as diisocyanate, and ethylene glycol as chain extender are used. A polyurethane impregnating solution was prepared by obtaining polyurethane by a conventional method and diluting with DMF so that the solid content was 12% by weight.

  Furthermore, after impregnating with this polyurethane impregnation liquid so that it might become 40% of solid content, while performing wet coagulation with the water adjusted to 40 degreeC, DMF and PVA were removed with 85 degreeC warm water. Next, after brushing with # 200 mesh sandpaper, Sumikaron Blue S-BBL200 (manufactured by Sumika Chemtex Co., Ltd.) was used with a flow dyeing machine at a concentration of 20% owf, 120 ° C., 45 minutes. Stained with

The leather-like sheet thus obtained had a basis weight of 320 g / cm ² and an apparent density of 0.249 g / cm ³ . Further, when the cross-sectional photograph is observed, the polyurethane porous body is present together with the fibers, and the polyurethane film-like material is present, and the napped length is long (the napped length is 1.0 mm), and has a suede appearance. As a result of the abrasion resistance test, it was 0 pills and a weight loss of 7 mg.

Comparative Example 2
Using the ultrafine short fiber nonwoven fabric (A) obtained in Example 1, and then dyeing in the same manner as in Example 1 with a liquid dyeing machine, the calender press heated at a processing rate of 150 ° C. and 5 m / min, The thickness was compressed 0.6 times. Then, after raising with # 500 mesh sandpaper, softener and fine particles were applied in the same manner as in Example 1 to obtain a leather-like sheet.

The leather-like sheet thus obtained had a basis weight of 289 g / cm ² and an apparent density of 0.488 g / cm ³ . Further, the entire sheet formed a dense fiber structure, and although a polyurethane film was not observed, the napped length was long (napped length 800 μm) and the appearance was suede. In addition, as a result of the abrasion resistance test, one pill was found and the abrasion loss was 2 mg.

Claims (16)

A film-like material comprising a short fiber nonwoven fabric having a single fiber fineness of 0.0001 to 0.5 dtex, an apparent density of 0.300 to 0.700 g / cm ³ , a napped length of 1 to 500 μm, and an elastic polymer Nubuck leather-like sheet-like material characterized by the absence of The nubuck leather-like sheet-like material according to claim 1, wherein the elastic polymer is present in an amount of 10% by weight or less. The nubuck leather-like sheet-like material according to claim 1, which is substantially made of a fiber material. The nubuck-like leather-like leather according to any one of claims 1 to 3, wherein the short fibers constituting the nonwoven fabric include those having a fiber length of 1 to 10 cm, and the short fibers are entangled with each other. Sheet material. The nubuck-like leather-like sheet-like material according to any one of claims 1 to 4, wherein the short fibers are made of polyester fibers and / or polyamide fibers. The nubuck leather-like sheet-like material according to any one of claims 1 to 5, wherein a woven fabric or a knitted fabric is laminated. The nubuck according to any one of claims 1 to 6, wherein, in the abrasion test in the Martindale method, the weight loss after 20,000 wears is 20 mg or less and the number of pills is 5 or less. Leather-like sheet. The nubuck leather-like sheet-like material according to any one of claims 1 to 7, wherein the fiber material contains fine particles. The nubuck leather-like sheet-like material according to claim 8, wherein the fine particles have a particle size of 0.001 to 30 µm. A composite short fiber nonwoven fabric was produced by a needle punch method using a composite short fiber of 1 to 10 dtex capable of generating ultrafine fibers of 0.0001 to 0.5 dtex, and then subjected to a high-speed fluid treatment at a pressure of at least 10 MPa. Then, the nubuck-like leather-like sheet-like manufacturing method characterized by carrying out the raising process and pressing. The method for producing a nubuck leather-like sheet-like material according to claim 10, wherein after the needle punching, the ultrathinning treatment is performed before the high-speed fluid treatment and / or simultaneously with the high-speed fluid treatment. The method for producing a nubuck-like leather-like sheet-like material according to claim 10 or 11, wherein, before the high-speed fluid treatment, the split treatment is performed on two or more sheets perpendicular to the thickness direction. The method for producing a nubuck leather-like sheet-like material according to any one of claims 10 to 12, wherein the thickness is pressed to 0.1 to 0.8 times. The method for producing a nubuck leather-like sheet-like material according to any one of claims 10 to 13, wherein after the raising treatment, press treatment is performed before or after dyeing, or both before and after dyeing. The nubuck leather-like sheet-like material according to any one of claims 10 to 14, wherein the water-dispersed elastic polymer is added in an amount of 0.1 to 10% by weight after the high-speed fluid treatment. The method for producing a nubuck leather-like sheet-like material according to claim 15, wherein the water-dispersed elastic polymer is applied and then the press treatment is performed.