JP4419669B2 - Leather-like sheet and method for producing the same - Google Patents

Description

  The present invention relates to a leather sheet having a high color density and excellent dyeing fastness, and a method for producing the same. More specifically, the present invention relates to a leather-like sheet-like material having a high color density and mainly composed of a fiber material having excellent dyeing fastness, sufficient physical properties, flexibility, and smooth touch, and a method for producing the same.

  Conventionally, as a suede-like leather-like sheet-like material in which ultrafine fibers are entangled, those obtained by raising ultrafine fibers on the surface of a nonwoven fabric provided with a polymer elastic body are provided and applied to a nonwoven fabric substrate. Polyurethane is generally used as the elastic polymer. In such a leather-like sheet-like material field, there has been a demand for higher grades in recent years, and there is a demand for a material that satisfies the physical properties such as appearance, texture, color development, and surface properties such as wear resistance. In order to obtain a smooth touch and high-quality surface quality, it is necessary to make the fibers used thin. However, as the fiber becomes thinner, the surface area of the fiber increases because the surface area of the fiber increases, the apparent color density decreases, and there is a drawback that it is difficult to obtain a sheet-like material having a high color density.

  To date, many attempts have been made to improve the color developability of ultrafine fibers.

  For example, it has been proposed to dye an easily dyeable resin on the surface of a fiber napping sheet (see, for example, Patent Document 1). Although this method improves the color developability to some extent, there is a drawback that the raised surface is less smooth and the texture is cured.

Further, fibers containing 30% or more of fine fibers having a fineness of 0.01 to 0.6 dtex are entangled with a base fabric made of a knitted fabric to form an entangled structure, colored in black, and a polymer elastic body. A black colored non-woven fabric has been proposed which has an L ^{* value} of 12 or less and a ^* and b ^* values in the range of −1 to +1 (see, for example, Patent Document 2). However, this can be achieved with a combination of acrylonitrile fiber having excellent color development and a cationic dye, but is difficult to achieve with other fibers and dyes.

  Further, it has been proposed to use ultrafine fiber bundles in which ultrafine fibers having different finenesses are mixed, and to control the fineness and distribution to have both coloring property, texture and surface physical properties. For example, fine fibers (fineness Ds) are arranged within 1/4 of the radius from the outer periphery of the fiber bundle, and ultrafine fibers (fineness Dc) are arranged within 2/3 of the radius from the center to define the fineness ratio (3. A method for producing a leather-like sheet-like product formed by forming an entangled nonwoven fabric composed of fiber bundles (0Dc ≦ Ds), and then applying and dyeing a polymer elastic body has been proposed (for example, see Patent Document 3). However, according to the knowledge of the present inventors, although a certain degree of color development improvement effect is recognized by this method, since a fiber with high fineness is localized on the sheet surface, a sheet-like material having a smooth touch is obtained. There is a drawback that it is difficult.

It has been difficult for these conventional proposals to balance a soft texture, strength, and color development in a leather-like sheet made of ultrafine fibers. As a result of intensive studies, the present inventors have found that it is possible to achieve this balance by substantially not including a polymer elastic body, and have reached the present invention.
JP-A-55-506 JP 2003-27380 A JP 2002-180329 A

  The present invention can be used for shoes, furniture, clothing, and the like, and has a high color density with sufficient physical properties, a soft texture, a smooth touch, and a fastness even though it does not substantially contain a polymer elastic body. An excellent leather-like sheet and a method for producing the same are provided.

In order to solve the above problems, the present invention has the following configuration. That is,
(1) A leather-like sheet-like material containing a polyester-based ultrafine fiber having a single fiber fineness of 0.0001 to 0.5 dtex derived from a sea-island type composite fiber, and the leather-like sheet is extremely fine by high-speed fluid treatment Consists of non-woven fabric in which short fibers are entangled with each other , substantially made of a fiber material, subjected to raising treatment, and the leather-like sheet is dyed, and the surface L ^* value is expressed by the following formula A leather-like sheet-like product characterized by satisfying (1).

L ^* value ≦ 12 (1)
(2) a fiber length of 10 cm or less, a basis weight of 100 to 550 g / m ² , a fiber apparent density of 0.29 to 0.7 g / cm ³ , an ultrafine short fiber nonwoven fabric, a tear strength of 3 to 50 N, and The leather-like sheet-like material as described in (1) above, wherein the following formula (2) is satisfied.

Tensile strength (N / cm) ≧ 0.45 × weight per unit area (g / m ² ) −40 (2)
(3) The leather-like sheet-like material as described in (1) or (2) above, wherein the fineness of the ultrafine fiber is 0.001 to 0.3 dtex.

  (4) JIS L0860 (1996) 8.1A. The leather-like sheet-like material according to any one of (1) to (3) above, wherein the discoloration color in dry cleaning measured by the method is 4 or more.

  (5) In any one of the above (1) to (4), the color change in washing fastness measured based on JIS L0844 (1997) AI method is grade 4 or higher, and contamination is grade 3 or higher. The leather-like sheet material described.

  (6) The fastness to dry friction measured based on JIS L0849 (1996) 6.1.2 is grade 4 or higher, and the fastness to wet friction measured based on JIS L0849 (1996) 6.2.2 is grade 3 The leather-like sheet-like material according to any one of (1) to (5) above, which is as described above.

  (7) The leather-like sheet-like material according to any one of (1) to (6) above, wherein the light fastness measured based on JIS L0842 (1996) 6 method is grade 4 or higher.

  (8) JIS L1096 (1999) 8.17.5E. (12 kpa) In the wear test in the Martindale method, the weight loss after wearing 20000 times is 20 mg or less, and the number of pills is 5 or less. A leather-like sheet according to any one of the above.

( 9 ) A method for producing the leather-like sheet-like material according to any one of (1) to (8), wherein an ultrafine fiber generation type short capable of generating 0.0001 to 0.5 dtex ultrafine fiber is provided. After the fibers are entangled by the needle punch method, ultrafine fibers are generated to form an ultrafine short fiber nonwoven fabric, and then entangled again by performing high-speed fluid treatment at a pressure of at least 10 MPa, and then the dye concentration using a disperse dye A method for producing a leather-like sheet, characterized by dyeing with 15 to 70% owf and then washing.

( 10 ) The method for producing a leather-like sheet-like material as described in ( 9 ) above, wherein at least one of the dyes to be used is azo.

( 11 ) The method for producing a leather-like sheet-like material as described in ( 10 ) above, wherein the dyeing temperature is in the range of 125 to 150 ° C.

( 12 ) The method for producing a leather-like sheet according to any one of ( 9 ) to ( 11 ), wherein a brushing treatment is performed with sandpaper before dyeing.

  According to the present invention, it is possible to provide a leather-like sheet having a high color density and excellent dyeing fastness.

  Further, according to the present invention, a leather-like sheet-like material having excellent color developability and fastness that can be used for shoes, furniture, car seats, clothing, and the like can be obtained.

The leather-like sheet material of the present invention is dyed and has a high color density, and the L ^* value on the surface of the leather-like sheet material satisfies the following formula (1). is important.

L ^* value ≦ 12 (1)
If the L ^* value does not satisfy this formula, a leather-like sheet having a high color density cannot be obtained. Moreover, it is preferable that the L ^* value on the surface of the leather-like sheet satisfies the following formula (3).

L ^* value ≦ 11.5 (3)
In order to obtain the L ^* value, it is important that the leather-like sheet material of the present invention is substantially free of a polymer elastic body and is made of a fiber material. Furthermore, for example, the dye concentration is 15 to 70% by weight, dyeing is performed at a temperature in the range of 125 to 150 ° C., and at least one of the dyes to be used may be a combination such as an azo dye having high color developability. It is preferable.

In addition, L ^* value is measured with MINOLTA SPECTROPHOMETER CM-3700d (manufactured by Minolta Co., Ltd.), D65 light source, viewing angle is 10 degrees, and is color-coded according to JIS Z8729.

  Moreover, the leather-like sheet material of the present invention is composed of at least a non-woven fabric, which makes it possible to obtain a leather-like texture. As long as it includes a nonwoven fabric, it may include a woven or knitted fabric laminated.

  In order for the above-described leather-like sheet-like material of the present invention to be composed of a nonwoven fabric and to be substantially made of a fiber material, it is an effective means to improve the strength of the leather-like sheet-like material itself, particularly at the time of dyeing. It is important to have enough strength to withstand action and sufficient quality and physical properties when it becomes a product.

  The leather-like sheet-like material is suede like natural leather, nubuck, and has an excellent surface appearance of silver surface, and particularly preferred in the present invention is the appearance of napped tone such as suede and nubuck, It has a smooth touch and excellent lighting effects.

  In the leather-like sheet material of the present invention, the single fiber fineness of the fibers constituting the nonwoven fabric is in the range of 0.0001 to 0.5 dtex. Preferably it is 0.001-0.3 dtex, More preferably, it is 0.005-0.15 dtex, More preferably, it is 0.005-0.09 dtex. If it is less than 0.0001 dtex, a leather-like sheet having a high color density cannot be obtained, and the strength decreases, which is not preferable. On the other hand, if it exceeds 0.5 dtex, the texture becomes stiff and problems such as deterioration of the surface quality occur, which is not preferable. Moreover, the fiber of the fineness exceeding said range may be contained in the range which does not impair the effect of this invention.

  The leather-like sheet-like product of the present invention is made of a short fiber nonwoven fabric in terms of excellent quality and texture, and the fiber length is preferably 10 cm or less, and more preferably 7 cm or less. 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 method for producing the nonwoven fabric. However, if it is less than 0.1 cm, it tends to drop off and the properties such as strength and wear tend to be lowered. It is preferable that it is 1 cm or more. Further, in consideration of physical properties such as strength and quality, it is preferable that the fiber length is not uniform. That is, it is preferable that a short fiber and a long fiber are mixed in a fiber length range 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 long fibers of 1 to 10 cm, preferably 2 to 7 cm are mixed can be exemplified. Here, for example, short fibers have a role for improving surface quality and densification, and long fibers have a role for obtaining high physical properties.

Further, the leather-like sheet-like material of the present invention preferably has a basis weight of 100 to 550 g / m ² . More preferably 120~450g / ^{m 2,} further preferably 140~350g / ^{m 2.} 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 550 g / m ² , the wear resistance tends to decrease, which is not preferable.

The leather-like sheet of the present invention preferably has a fiber apparent density of 0.29 to 0.7 g / cm ³ . More preferably the fibers apparent density of 0.3~0.65g / cm ^3, further preferably 0.33~0.6g / cm ^3. If it is less than 0.29 g / cm ³ , the abrasion resistance is particularly lowered, which is not preferable. ^{On the other hand} , if it exceeds 0.7 g / cm ³ , the texture becomes hard, which is not preferable.

  The leather-like sheet material of the present invention preferably has a tear strength in the vertical and horizontal directions in the range of 3 to 50N, and more preferably 5 to 30N. More preferably, it is 10-25N. If it is less than 3N, it is easy to break, the process passability is lowered, and stable production becomes difficult. On the other hand, if it exceeds 50N, it tends to be too soft in general, and it is difficult to balance with the texture. In order to obtain these tear strengths, it can be achieved by adjusting the apparent fiber density to an appropriate range, and generally the strength tends to decrease as the density increases. Moreover, it can also be improved by making it flexible by stagnation processing or the like.

  The leather-like sheet of the present invention preferably satisfies the following formula (2) in both the vertical and horizontal tensile strengths.

Tensile strength (N / cm) ≧ 0.45 × basis weight ^{(g / m 3) -40 ···} (2)
In addition, it is more preferable that the tensile strength in both the vertical and horizontal directions satisfies the following formula (4).

Tensile strength (N / cm) ≧ 0.5 × weight per unit area (g / m ³ ) −40 (4)
Further, it is more preferable that both the vertical and horizontal tensile strengths satisfy the following formula (5).

Tensile strength (N / cm) ≧ 0.6 × weight per unit area (g / m ³ ) −40 (5)
Tensile strength of the following formula (2): Tensile strength (N / cm) ≧ 0.45 × weight per unit area (g / m ³ ) −40 (2)
In a range that does not satisfy the above, in particular, a leather-like sheet material that does not substantially contain a polymer elastic body may cause problems such as blurring, which is not preferable. Moreover, although an upper limit is not specifically limited, Usually, it will be 250 N / cm or less.

  The leather-like sheet material of the present invention is JIS L 0860 (1996) 8.1A. In the dry cleaning test measured based on the law, it is preferable that the discoloration color of the test cloth determined by the gray scale defined in JIS L0804 is grade 4 or higher. If the discoloration color is less than the fourth grade, it is not preferable because the fading after dry cleaning is large and the quality is lowered.

  In addition, in the wash fastness test measured based on the JIS L0844 (1997) AI method, the color change of the test cloth determined by the gray scale defined in JIS L0804 is grade 4 or higher, and determined by the gray scale defined by L0805. It is preferable that the attached fabric is contaminated with a grade 3 or higher. If the discoloration color is less than the fourth grade, it is not preferable because the quality deteriorates due to fading after washing. In addition, when the attached fabric is less than the third grade, it is not preferable because other products washed in the lining or the same bath may be contaminated.

  Further, the leather-like sheet material of the present invention has a dry friction fastness measured by JIS L0849 (1996) 6.1.2 or higher, and measured by JIS L0849 (1996) 6.2.2. The wet friction fastness is preferably 3 or higher. When the dry friction fastness is less than 4th grade, it is not preferable because clothes tend to be contaminated in actual use. Further, when the wet friction fastness is less than the third grade, it is not preferable because clothes tend to be contaminated when used under wet conditions such as rain and sweat.

  Moreover, it is preferable that any aspect of the leather-like sheet-like material of the present invention has a light fastness measured based on JIS L0842 (1996) 6 of 4th or higher. If it does not satisfy the fourth grade, it is not preferable because it tends to be faded and the appearance quality deteriorates under outdoor use after washing, furniture, car seats, etc. under the use of sunlight.

  In addition, the leather-like sheet-like material of the present invention is 20,000 times in the abrasion resistance test measured based on the load for furniture (12 kPa) according to JIS L 1096 (1999) 8.17.5 E method (Martindale method). The weight loss of the test cloth after the number of wears is preferably 20 mg or less, more preferably 15 mg or less, still more preferably 10 mg or less, and the number of pills is preferably 5 or less, preferably 3 or less. More preferably, it is more preferably 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. Further, if the number of generated pills exceeds 5, it is not preferable because the quality deteriorates due to the appearance change when used.

  In order to obtain such wear resistance, the apparent fiber density is particularly important, and the higher the density, the better. Moreover, when a softening agent etc. are used in large quantities, the tendency to fall is seen. Therefore, it is important to set these conditions while balancing with the texture.

  Hereinafter, an example of the method for producing the leather-like sheet material of the present invention will be described.

  A preferable method for obtaining the leather-like sheet-like material of the present invention is to entangle ultrafine fiber-generating short fibers capable of generating 0.0001 to 0.5 decitex ultrafine fibers by the needle punch method, and then ultrafine fibers. Is formed into an ultra-fine short fiber nonwoven fabric, then subjected to high-speed fluid treatment at a pressure of at least 10 MPa, entangled again, then dyed at a dye concentration of 15 to 70% owf, and then subjected to reduction washing.

  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 to produce by using an island-in-sea type composite fiber or a split type composite fiber in that an ultrafine fiber can be obtained easily and stably. It is more preferable to manufacture with a sea-island type composite fiber in that an ultrafine fiber made of the same kind of polymer that can be dyed with the same kind of dye 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 And the like, and (4) a method of producing using a base such as Japanese Patent Publication No. 44-18369 and Japanese Patent Laid-Open No. 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. In addition, the component ratio at this time is preferably 0.3 to 0.99, more preferably 0.4 to 0.97, and more preferably 0.5 to 0.8 by weight ratio of island fibers to sea-island type composite fibers. Is more preferable. If it is less than 0.3, 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. For example, polyester, polyamide, polypropylene, polyethylene, etc. can be used as the island component depending on the intended use. However, in terms of dyeability, strength, and fastness, polyester is used. Preferably there is.

  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 and the like. In the present invention, polyethylene terephthalate, which is most commonly used, or a polyester copolymer mainly containing ethylene terephthalate units is preferably used.

  Examples of the polyamide that can be used in the present invention include polymers having an amide bond such as nylon 6, nylon 66, nylon 610, nylon 12, and the like.

  The polymer used as the sea component of the sea-island type composite fiber is not particularly limited as long as it has chemical properties such as solubility and decomposability different from 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 dodecylbenzenesulfonate, bisphenol A compound, isophthalic acid, adipic acid, dodecadioic acid, Polyester etc. which copolymerized cyclohexyl carboxylic acid etc. 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 copolyester 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.

  The fiber is then cut to a suitable length. It is important that the leather-like sheet-like material of the present invention is made of an ultrafine short fiber nonwoven fabric in terms of excellent quality and texture. Therefore, it is necessary to cut the above-described fiber to an appropriate length, and the length is set to 10 cm or less in consideration of productivity and the texture of the obtained product. Preferably it is 7 cm or less. 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

Next, the short fibers are made into a non-woven fabric. As a method for forming the nonwoven fabric, a dry method in which the web is obtained using a card, a cross wrapper, or a random web, or a wet method such as a papermaking method can be employed. In the present invention, the needle punch method and the high-speed fluid flow treatment are used. A dry method that can easily combine seed entanglement methods is preferred. 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 punch according to the present invention, it is preferable that the fibers are sufficiently entangled rather than merely serving as temporary fixing for obtaining process passability as described above. Accordingly, the needle punch driving density of 100 / cm ² or more is preferably high, 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 shrunk by dry heat or wet heat, or both, further densified, and subjected to ultrafine processing. Next, it is preferable to perform split processing on two or more sheets perpendicular to the thickness direction.

  Furthermore, it is preferable that the ultrafine fibers are entangled by performing high-speed fluid flow treatment after the ultrafine treatment, simultaneously with the ultrafine treatment, or simultaneously with the ultrafine treatment. Although it is possible to combine the high-speed fluid flow treatment with the ultrafine processing, it is preferable to perform the high-speed fluid flow treatment even after at least the ultrafine processing is mostly completed in order to further promote the entanglement between the ultrafine fibers, Furthermore, it is preferable to perform the high-speed fluid flow process after performing the ultrafine process.

  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 particular, a method for producing a composite short fiber nonwoven fabric with ultrafine fiber-generating fibers using an alkali-degradable sea component and then treating it with a neutral-alkaline aqueous solution to make it ultrafine is based on the working environment without using a solvent. Since it is preferable, it is one of the preferable embodiments of the present invention. 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 an organic or inorganic salt may be used as long as it exhibits a pH in the above range. 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. Further, 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 residual chemicals and decomposition products, and then dried.

  As the high-speed fluid flow treatment, it is preferable to perform a water jet punch treatment 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. However, if the nozzle hole diameter is less than 0.06 mm, nozzle clogging is likely to occur. This is not preferable because there is a problem that the cost is increased due to the necessity of highly filtering water.

  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 by cutting the fiber. 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 focused are mainly entangled, but in the present invention, the entanglement by the ultrafine fiber bundles is 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, and it is also possible to improve surface properties 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 possible to move the nozzle head and the nonwoven fabric relatively, or insert a wire mesh between the nonwoven fabric and the nozzle after entanglement to perform watering treatment.

  Subsequently, when the leather-like sheet-like material of the present invention obtains a suede-like or nubuck-like leather-like sheet-like material, it is preferable that the ultra-short fiber non-woven fabric is subjected to raising treatment with sandpaper or a brush. Such raising treatment can be performed before or after dyeing, or before and after dyeing, but is more preferably performed before dyeing.

  Subsequently, this ultrafine short fiber nonwoven fabric is dyed. 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.

The dye concentration used is 15 to 70% owf (weight% of dye with respect to the weight of the leather-like sheet). Preferably it is 20 to 60% owf, more preferably 25 to 50% owf. If it is less than 15% owf, it becomes difficult to obtain the above-mentioned L ^* value, and a sheet-like material having a high color density cannot be obtained. On the other hand, if it exceeds 70% owf, the dispersion state of the dye becomes poor, color irregularities and specs due to secondary aggregation occur, leading to deterioration of surface quality and various fastnesses. In general, dyes used for dyeing fibers are usually mixed with additives such as dispersants and penetrants to obtain levelness in the pigment component, and inorganic salts to make the concentration constant. Although not generally stated, these additives are often contained, for example, in an amount of about 50 to 80% based on the total weight of the dye. The weight of the dye here refers to the total weight of the dye including the auxiliary agent mixed therein. Liquid type dye means the weight of the solid content. When using a dye with a small ratio of additives and a high ratio of the pigment component, it is preferable to set the dye concentration to be lower within the above range.

  As the kind of the dye to be used, a dye having excellent color developability and fastness, which is appropriately selected from disperse dyes, vat dyes, metal-containing dyes and the like depending on the polymer type of the leather-like sheet material, is preferable. Furthermore, in order to obtain a high color density, it is preferable that at least one of the dyes used is an azo dye having excellent color developability, and two or more azo dyes are more preferable. The azo dye herein refers to a dye containing an azo group (—N═N—) in the structure of the dye component of the dye. One monoazo dye, two disazo dyes, three or more polyazo dyes. Dyes and stilbene dyes containing a chromophore stilbene group in addition to azo groups, pyrazolone dyes having a pyrazolone ring, thiazole dyes having a thiazole ring, and the like are also included in the azo dye, and any azo dye is preferably used it can. In addition, pH adjusting agents such as acetic acid and sodium acetate, leveling agents, and dispersing agents can be appropriately added to the dyeing bath.

  A preferable method for obtaining the leather-like sheet-like material of the present invention having various dyeing fastnesses of dry cleaning, washing, friction, and light resistance within the above-mentioned range is substantially free of a polymer elastic body such as polyurethane and fiber. It is a leather-like sheet made of a material. The dye in the polymer elastic body easily migrates, and if the content of the polymer elastic body is large, it leads to a decrease in various fastnesses. The term “substantially free of a polymer elastic body” as used in the present invention means that the content of the polymer elastic body with respect to the fiber material is not positively applied in a large amount such as 20% by weight or more. For the purpose of improving texture, touch, texture, etc., for example, a small amount of about 0.1 to 3% by weight is not substantially included.

  Further, as the dye used, a disperse dye is preferable when the ultrafine fiber is a polyester fiber, and a metal-containing dye or a vat dye is preferable when the ultrafine fiber is a polyamide fiber. Furthermore, it is preferable from the viewpoint of fastness to use a polyester fiber as the ultrafine fiber. In order to obtain the fastness of the present invention, it is also possible to remove dyes and auxiliaries adhering to the surface of the leather-like sheet and the fiber entanglement point after dyeing and to improve the fastness of the product. Preferably done. As a cleaning method, a commonly used method can be used. For example, hydrosulfite, sodium hydroxide, a surfactant or the like is appropriately used, and the cleaning is preferably performed at a temperature in the vicinity of 80 to 85 ° C. for about 20 to 30 minutes.

  The dyeing of the leather-like sheet of the present invention preferably has a dyeing temperature in the range of 125 to 150 ° C. when the ultrafine fiber is a polyester fiber. If the temperature exceeds 125 ° C., the high color density of the present invention can be easily obtained. However, when the temperature exceeds 150 ° C., the quality and texture of the obtained leather-like sheet are deteriorated. The dyeing time is preferably about 30 to 60 minutes at the above temperature, and then gradually lowered to around 60 to 70 ° C. for preventing wrinkles.

  Next, the leather-like sheet material of the present invention can be provided with a finishing agent for the purpose of imparting functionality, adjusting the texture, and the like. Finishing agents used are usually used finishing agents such as anti-pilling agents, softeners, flame retardants, antistatic agents, water repellents, antioxidants, UV absorbers, and light stabilizers, depending on the desired texture and function. However, depending on the conditions, for example, a treating agent with flexibility, smoothness, etc. may have physical properties, particularly abrasion resistance, of a leather-like sheet-like product. Since it tends to be worse, it is necessary to set conditions while balancing physical properties and texture. Moreover, the method to provide can be performed by any of a bathing method and / or a padding method, for example.

Thus, according to the present invention, it is possible to obtain a leather-like sheet-like material having a high color density and excellent in fastness and having sufficient physical properties and quality.
Moreover, the leather-like sheet-like material of the present invention can be preferably used for applications such as clothing, furniture, car seats, and miscellaneous goods, particularly car seats and clothing.

Hereinafter, the present invention will be described more specifically with reference to examples. In addition, the physical-property value in an Example was measured by the method described below. Evaluation was made by arbitrarily sampling at least five locations from the large dimensions, and making measurements based on the average values.
(1) L ^* value Measured with MINOLTA SPECTROPHOMETER CM-3700d (manufactured by Minolta Co., Ltd.), D65 light source, viewing angle is 10 degrees, L ^* a ^* b ^* color system (JIS Z8729) Colored.
(2) Fabric weight and apparent fiber density Fiber apparent density is a weight per unit volume (cm ³ ) obtained by measuring a fabric weight according to JIS L1096 8.4.2 (1999) and then measuring its thickness. The average value of the fiber was used as the apparent fiber density. The thickness was measured using a dial thickness gauge (Ozaki Mfg. Co., Ltd., product name “Peacock H”), 10 samples were measured, and the average value was used.
(3) Tensile strength According to JIS L 1096 8.12.1 (1999), a sample having a width of 5 cm and a length of 20 cm was taken, and a tensile speed of 10 cm / min was obtained with a constant-speed extension type tensile tester at a gripping interval of 10 cm. And stretched. The obtained value was converted to the tensile strength per 1 cm width.
(4) Tear strength Measured based on JIS L 1096 8.15.1 (1999) D method (penjuram method).
(5) Martindale abrasion test JIS L 1096 (1999) 8.17.5 After wearing out 20000 times in the abrasion resistance test measured according to the 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.
(6) Fastness to dry cleaning JIS L 0860 (1996) 8.1A. Measured based on the method.
(7) Fastness to washing Measured based on JIS L0844 (1997) AI method.
(8) Fastness to dry friction Measured based on JIS L0849 (1996) 6.1.2 method.
(9) Wet friction fastness It measured based on JIS L0849 (1996) 6.2.2 method.
(10) Light fastness measured according to JIS L0842 (1996) 6 method (11) Diameter of single fiber (d)
Using a scanning electron microscope, a photograph in which the cross section of the leather-like sheet was magnified 3000 times was taken, measured directly from this photograph, and calculated. Arbitrary 100 pieces were selected and measured, and the average value was obtained. However, when the cross section was not a perfect circle, the maximum and minimum diameters of the cross section were measured and the average was obtained.

Example 1
A web was prepared through a card and a cross wrapper using sea island type composite short fibers having a composite 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 1500 pieces / cm ² to obtain a composite short fiber nonwoven fabric with an apparent fiber density of 0.21 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, 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 an ultrafine short fiber nonwoven fabric having a single fiber fineness of about 0.04 dtex was obtained. Next, after splitting into two pieces perpendicular to the thickness direction using a standard splitting machine manufactured by Murota Manufacturing Co., Ltd., water having a nozzle diameter of 0.1 mm and a nozzle head with an interval of 0.6 mm is used. The front and back surfaces were treated with a jet punch at a processing speed of 1 m / min at 10 MPa and 20 MPa, and entangled with PVA removal. Next, after brushing with sandpaper, a liquid dyeing machine (circular dyeing machine (manufactured by Nisaka Seisakusho Co., Ltd.)) was used and a black dye containing two kinds of azo dyes at a concentration of 30% owf was 120. After dyeing at 45 ° C. for 45 minutes, wash in a liquid bath of hydrosulfite 4 g / l, sodium hydroxide 1.5 g / l and surfactant 0.2 g / l at 80 ° C. for 20 minutes, and further at 40 ° C. Washed with hot water for 20 minutes, dehydrated with mangle, mangled with a finishing agent mixed with Silstat 1173 (manufactured by Sanyo Chemical Co., Ltd.) 1 g / l and Beviner S-783 (manufactured by Maruhishi Oil Chemical Co., Ltd.) 3 g / l. Was applied by a pad dry method. The wet pick-up rate of the liquid at this time was 153% by weight with respect to the sheet-like material. Thereafter, it was dried at 100 ° C. to obtain a suede-like leather-like sheet. The obtained sheet-like material has a very solid and high-quality appearance, and when the L ^* value is measured, the L ^* value is 11.3, which is a deep black sheet-like material. It was. The results of evaluating physical properties and dyeing fastness are shown in Table 1. As shown in the table, it was a leather-like sheet having excellent physical properties and dyeing fastness.

Example 2
A leather-like sheet was obtained in the same manner as in Example 1 except that the dyeing temperature was 125 ° C and the washing temperature was 85 ° C. The results of evaluating the physical properties and fastness are shown in Table 1. As shown in the table, the L ^* value was low and deep black sheet-like material, and it was a leather-like sheet material excellent in physical properties and dyeing fastness.

Example 3
A leather-like sheet was obtained by the same treatment as in Example 1 except that the raw cotton supply amount was halved at the time of web preparation and no split treatment was performed. The results of evaluating the physical properties and fastness are shown in Table 1. As shown in the table, the L ^* value was low and deep black sheet-like material, excellent in dyeing fastness, and a leather-like sheet-like material having higher physical properties than Example 1.

Example 4
Except for using 20 parts of polystyrene as the sea component and 8 parts of composite fineness consisting of 80 parts of polyethylene terephthalate as the island component, 25 islands, sea-island type composite fiber with a fiber length of 51 mm (the fineness of the island component is about 0.16 decitex) A leather-like sheet was obtained by the same treatment as in Example 1. The results of evaluating the physical properties and fastness of the sheet are shown in Table 1. It was excellent in physical properties and dyeing fastness, had a lower L ^* value than Examples 1 to 3, and was a deep black sheet.

Comparative 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 3000 / cm ² to obtain a composite short fiber nonwoven fabric. 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, 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 an ultrafine short fiber nonwoven fabric having a single fiber fineness of about 0.04 dtex was obtained.
Thereafter, a solution obtained by diluting a polycarbonate polyurethane with dimethylformamide so that the solid content is 12% by weight is impregnated so as to be about 35 parts per island fiber as a polyurethane solid content, wet coagulated, and heated at 95 ° C. It was dried after removing PVA in water. Subsequently, it split-processed into two perpendicular | vertical with respect to the thickness direction using the standard type | mold splitting machine by Murota Manufacturing Co., Ltd. Then, after raising with sandpaper, dyeing and post-processing were performed in the same manner as in Example 1 to obtain a suede-like leather-like sheet. When the L ^* value of the obtained sheet-like material was measured, the L ^* value was 16.9, and it was a black sheet-like material lacking in depth. The results of evaluating physical properties and dyeing fastness are shown in Table 1. As shown in the table, it was a leather-like sheet lacking in dyeing fastness.

Comparative Example 2
A web was prepared through a card and a cross-wrapper using a sea-island type composite fiber having a composite 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 polyester as an island component. Subsequently, it was processed with a 1 barb type needle punch at a driving density of 1500 pieces / cm ² to obtain a composite short fiber nonwoven fabric with an apparent fiber density of 0.21 g / cm ³ . Subsequently, both surfaces were treated at 10 MPa and 20 MPa at a processing speed of 1 m / min with a water jet punch composed of a nozzle head having a hole diameter of 0.1 mm and an interval of 0.6 mm, and entangled. Next, it is immersed in a 12% aqueous solution of polyvinyl alcohol (PVA) heated to about 95 ° C. so that the amount of adhesion is 25% of the weight of the nonwoven fabric in terms of solid content. And dried at 100 ° C. to remove moisture. The obtained sheet was treated with trichrene at about 30 ° C. until the polystyrene was completely removed, and an ultrafine short fiber nonwoven fabric sheet having a single fiber fineness of about 0.04 dtex was obtained. Then, after raising with a sandpaper, dyeing was carried out in the same manner as in Example 1. As a result, tearing occurred during dyeing, and a leather-like sheet could not be obtained.

Comparative Example 3
A web was prepared through a card and a cross-wrapper using a sea-island type composite fiber having a composite 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 polyester as an island component. Subsequently, it was processed with a 1 barb type needle punch at a driving density of 1500 pieces / cm ² to obtain a composite short fiber nonwoven fabric with an apparent fiber density of 0.21 g / cm ³ . Subsequently, both surfaces were treated at 10 MPa and 20 MPa at a processing speed of 1 m / min with a water jet punch composed of a nozzle head having a hole diameter of 0.1 mm and an interval of 0.6 mm, and entangled. Next, it is immersed in a 12% aqueous solution of polyvinyl alcohol (PVA) heated to about 95 ° C. so that the amount of adhesion is 25% of the weight of the nonwoven fabric in terms of solid content. And dried at 100 ° C. to remove moisture. The obtained sheet was treated with trichrene at about 30 ° C. until the polystyrene was completely removed, and an ultrafine short fiber nonwoven fabric sheet having a single fiber fineness of about 0.04 dtex was obtained. Next, after impregnating the emulsion polyurethane (“Evaphanol APC-55” manufactured by Nikka Chemical Co., Ltd.) so as to give 20% in solid content, heat treatment was performed at 150 ° C. for 10 minutes. Subsequently, it dye | stained similarly to Example 1 with the liquid-flow dyeing machine, and obtained the leather-like sheet-like material. Table 1 shows the results of evaluating the physical properties and fastness of the obtained sheet-like material. As shown in the table, the sheet was lacking in black depth and inferior in fastness.

Claims (12)

A leather-like sheet-like material comprising a polyester-type ultrafine short fiber having a single fiber fineness of 0.0001 to 0.5 dtex derived from a sea-island type composite fiber, and the leather-like sheet is made of ultrafine short fibers by high-speed fluid treatment Is composed of a nonwoven fabric intertwined , substantially made of a fiber material, subjected to raising treatment, and the leather-like sheet is dyed, and the surface L ^* value is expressed by the following formula (1) A leather-like sheet material characterized by satisfying
L ^* value ≦ 12 (1) Including an ultra-fine short fiber nonwoven fabric having a fiber length of 10 cm or less, a basis weight of 100 to 550 g / m ² , a fiber apparent density of 0.29 to 0.7 g / cm ³ , a tear strength of 3 to 50 N, and the following formula ( The leather-like sheet-like product according to claim 1, wherein 2) is satisfied.
Tensile strength (N / cm) ≧ 0.45 × weight per unit area (g / m ² ) −40 (2) The leather-like sheet-like product according to claim 1 or 2, wherein the fineness of the ultrafine fiber is 0.001 to 0.3 dtex. JIS L0860 (1996) 8.1A. The leather-like sheet-like material according to any one of claims 1 to 3, wherein the discoloration color in dry cleaning measured by a method is grade 4 or higher. The leather-like sheet-like sheet according to any one of claims 1 to 4, wherein the discoloration color in washing fastness measured based on JIS L0844 (1997) AI method is grade 4 or higher and contamination is grade 3 or higher. object. The fastness to dry friction measured according to JIS L0849 (1996) 6.1.2 is grade 4 or higher, and the fastness to wet friction measured according to JIS L0849 (1996) 6.2.2 is grade 3 or higher. The leather-like sheet-like article according to any one of claims 1 to 5. The leather-like sheet-like product according to any one of claims 1 to 6, wherein the light fastness measured based on JIS L0842 (1996) 6 method is grade 4 or higher. JIS L1096 (1999) 8.17.5E. (12 kpa) In the abrasion test in the Martindale method, the weight loss after wearing 20000 times is 20 mg or less, and the number of pills is 5 or less. The leather-like sheet material described . A method for producing the leather-like sheet-like material according to any one of claims 1 to 8, wherein a sea-island type composite ultrafine fiber generating short fiber capable of generating 0.0001 to 0.5 decitex ultrafine fiber is used as a needle. After entanglement by the punch method, ultrafine fibers are generated to form an ultrafine short fiber non-woven fabric, and then subjected to high-speed fluid treatment at a pressure of at least 10 MPa and entangled again, and then a dye concentration of 15 to 70 using a disperse dye. A method for producing a leather-like sheet, characterized by dyeing with% owf and then washing. The method for producing a leather-like sheet according to claim 9 , wherein at least one of the dyes used is azo . The method for producing a leather-like sheet according to claim 10 , wherein the dyeing temperature is in the range of 125 to 150 ° C. The method for producing a leather-like sheet-like material according to any one of claims 9 to 11, wherein a raising process is performed with sandpaper before dyeing.