Artificial leather and vehicle interior covering materials containing the same

Abstract

To provide artificial leather that contains plant fibers and has both flexibility and abrasion resistance by increasing the degree of intertwining of the fibers, and to provide a covering material for vehicle interiors that includes the artificial leather.SOLUTION: This invention relates to an artificial leather comprising a substrate made of fiber cloth and a surface fiber layer laminated on the substrate, which satisfies the following characteristics (1) to (3): (1) the substrate and the surface fiber layer both contain plant fibers; (2) the plant fiber content in the artificial leather is 50 mass% or more relative to the total mass of the artificial leather; and (3) the peel strength between the substrate and the surface fiber layer is 2 N / cm or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to artificial leather and a covering material for vehicle interiors containing the same. [Background technology]

[0002] Conventionally, artificial leather made from synthetic fibers has been widely used for applications such as furniture, clothing, automobile interiors, shoes, and bags. However, in recent years, there has been a growing demand for artificial leather made from plant fibers.

[0003] The following Patent Document 1 discloses that by mixing leaf fibers and hardening polymer fibers in a certain ratio and thermally fusing the hardening polymer fibers, artificial leather with a certain tensile strength can be obtained while using plant raw materials. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-106158 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the invention described in Patent Document 1 does not take into consideration the entanglement of fibers to suppress surface wear, and the abrasion resistance is insufficient without a resin coating on the surface. Furthermore, when the invention described in Patent Document 1 is applied to the surface with a resin coating, the abrasion resistance is improved, but the flexibility is significantly reduced, making it difficult to obtain a good texture.

[0006] In view of the above-described state of the art, the problem to be solved by the present invention is to solve the problems of the above-described conventional art and to provide an artificial leather that contains plant fibers and has enhanced inter-fiber entanglement, thereby achieving both flexibility and abrasion resistance, and a skin material for vehicle interiors that includes the artificial leather. [Means for solving the problem]

[0007] As a result of extensive research and experimentation to solve the above-mentioned problems, the inventors unexpectedly discovered that an artificial leather containing plant fibers and having the following configuration can solve the above-mentioned problems, and thus completed the present invention.

[0008] That is, the present invention is as follows. [1] An artificial leather comprising a substrate made of a fiber cloth and a surface fiber layer laminated on the substrate, the artificial leather having the following characteristics (1) to (3): (1) The substrate and the surface fiber layer both contain plant fibers; (2) The content of plant fibers in the artificial leather is 50% by mass or more based on the total mass of the artificial leather; and (3) The peel strength between the substrate and the surface fiber layer is 2 N / cm or more; Artificial leather that satisfies the above. [2] The artificial leather according to [1], wherein the content of plant fibers in the base material is 50% by mass or more relative to the total mass of the base material. [3] The artificial leather according to [1] or [2], wherein the artificial leather contains a binder resin. [4] The artificial leather according to [3], wherein the content of the binder resin is more than 0% by mass and 20% by mass or more relative to the total mass of the artificial leather. [5] The artificial leather according to [3] or [4], wherein the binder resin is a polyurethane resin. [6] The artificial leather according to [5], wherein the polyurethane resin is a water-dispersed polyurethane resin. [7] The artificial leather according to any one of [1] to [6], wherein the L / D value, which is the ratio of the fiber length L to the single fiber diameter D of the vegetable fibers contained in the surface fiber layer, is 50 or more and 4000 or less. [8] The artificial leather according to any one of [1] to [7], wherein the surface fiber layer contains cellulose fibrils. [9] The specific surface area of the fibers constituting the surface fiber layer is 0.10 m 2 The artificial leather according to any one of [1] to [8] above, wherein the surface roughness is 1 / g or more.

[10] Further features below (4): (4) The surface fiber layer has a specific surface area of 0.5 m 2 / g or more 1.5m 2 / g or less of cellulose fibrils; The artificial leather according to any one of the above [1] to [9], which satisfies the above.

[11] The artificial leather according to any one of [1] to

[10] , wherein the surface fiber layer contains synthetic fibers.

[12] The artificial leather according to

[11] , wherein the content of synthetic fibers in the surface fiber layer is 25% by mass or more and 50% by mass or less of the total mass of fibers contained in the surface fiber layer.

[13] The artificial leather according to any one of [1] to

[12] above, wherein the substrate is a woven fabric.

[14] The artificial leather according to

[13] , wherein the cover factor CF of the woven fabric is 15 or more and 40 or less.

[15] The artificial leather according to any one of [1] to

[13] , wherein the height Sz of the surface irregularities of the artificial leather is 200 μm or more and 600 μm or less.

[16] The artificial leather according to any one of [1] to

[15] , wherein the surface of the artificial leather is napped.

[17] The artificial leather according to any one of [1] to

[16] above, wherein the artificial leather is dyed.

[18] A skin material for vehicle interiors, comprising the artificial leather according to any one of [1] to

[17] above. [Effects of the Invention]

[0009] The artificial leather of the present invention and the vehicle interior covering material containing the same contain plant fibers and yet are both flexible and abrasion-resistant. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described in detail. One embodiment of the present invention is an artificial leather including a substrate made of a fiber cloth and a surface fiber layer laminated on the substrate, the artificial leather having the following characteristics (1) to (3): (1) The substrate and the surface fiber layer both contain plant fibers; (2) The content of plant fibers in the artificial leather is 50% by mass or more based on the total mass of the artificial leather; and (3) The peel strength between the substrate and the surface fiber layer is 2 N / cm or more; It is an artificial leather that satisfies the above requirements.

[0011] [Artificial leather] The artificial leather of this embodiment includes a substrate made of a fiber cloth and a surface fiber layer laminated on the substrate, and the surface fiber layer may be laminated on only one side of the substrate, or on both sides of the substrate. The artificial leather of this embodiment is produced, for example, by laminating staple fibers on one or both sides of the substrate by a papermaking method, and then entangling the staple fibers with each other and the staple fibers with the substrate by an entanglement treatment. In this specification, "artificial leather" means an artificially produced leather-like sheet material.

[0012] Both the substrate and the surface fiber layer contain plant fibers, such as natural cellulose fibers from cotton, linen, ramie, hemp, pulp, bamboo, pineapple, banana, coconut, kapok, kenaf, and shell ginger.

[0013] The plant fiber content of the artificial leather of this embodiment is 50% by mass or more of the total mass of the artificial leather. The higher the plant fiber content, the smaller the environmental impact during production and disposal, and the higher thermal conductivity of the plant fiber results in a better feel.

[0014] The artificial leather of this embodiment has a peel strength between the substrate and the surface fiber layer of 2 N / cm or more, preferably 3 N / cm or more. When the peel strength is 2 N / cm or more, the entanglement strength between the fibers is high, so that sufficient abrasion resistance to prevent surface damage in actual use can be obtained without a resin coating, and flexibility is also improved.

[0015] To achieve a peel strength of 2 N / cm or more between the surface fiber layer and the substrate, it is preferable to adjust the type, single fiber length, thickness, and twist number of the staple fibers and spun yarns used in the surface fiber layer and the substrate, the basis weight, thickness, and density of the surface fiber layer and the substrate, and the processing conditions in the entanglement step. Known entanglement methods include hydroentanglement and needle punching, with hydroentanglement being preferred from the viewpoint of preventing damage to the substrate. In the case of hydroentanglement, the peel strength can be adjusted by adjusting the diameter of the nozzle spraying the water stream, the water pressure and direction of the sprayed water stream, etc. Furthermore, a binder resin can be added to improve the peel strength between the surface fiber layer and the substrate. In order to achieve a peel strength of 2 N / cm or more, it is particularly important to carry out hydroentangling.

[0016] [Surface fiber layer] The L / D value, which is the ratio of the fiber length L to the single fiber diameter D of the vegetable fibers contained in the surface fiber layer, is preferably 50 or more, more preferably 100 or more, and is preferably 4000 or less, more preferably 3000 or less, and even more preferably 2000 or less. When the L / D value is 50 or more and 4000 or less, the short fibers are well dispersed and easily opened in the slurry when the short fibers are dispersed in water to prepare a slurry, the strength of the surface fiber layer is good, and pilling due to friction is less likely to occur. Furthermore, setting the thickness within the above range is effective in achieving a peel strength between the surface fiber layer and the substrate of 2 N / cm or more.

[0017] The surface fiber layer preferably contains cellulose fibrils from the viewpoint of increasing the static friction force and thereby further enhancing the entanglement force between fibers. Here, cellulose fibrils refer to fibers or bundles thereof called fibrils, which are made of natural cellulose and have a fiber diameter of several hundred nanometers to several millimeters. Examples of cellulose fibrils include fibrillated cellulose. Examples of fibrillated cellulose include independent fibrils peeled from the fiber surface or fine fibers formed by these fibrils, which are obtained by subjecting plant-derived materials such as pulp to a micronizing treatment using a device that applies high shear force, such as a high-pressure homogenizer, an ultra-high-pressure homogenizer, or a grinder.

[0018] The specific surface area of the fibers constituting the surface fiber layer is preferably 0.10 m from the viewpoint of mechanical strength. 2 / g or more, more preferably 0.20m 2 / g or more, more preferably 0.50m 2 / g or more, most preferably 0.80m 2 / g or more, and preferably 2.0m 2 / g or less, more preferably 1.6m 2 / g or less, more preferably 1.2m 2 / g or less. Here, the specific surface area of the fibers constituting the surface fiber layer is a value measured by the BET method.

[0019] The surface fiber layer has a specific surface area of 0.5m 2 / g or more 1.5m 2 The specific surface area of the cellulose fibrils contained in the surface fiber layer is preferably 0.6 m / g or less. 2 / g or more 1.0m 2 / g or less, more preferably 0.6m 2 / g or more 0.8m 2 / g or less. The specific surface area of the surface fiber layer is 0.5m 2 / g or more 1.5m 2 The content of cellulose fibrils of 0.1 to 1.0 g / g or less is preferably 20% by mass or more, more preferably 50% by mass or more, based on the total mass of the fibers contained in the surface fiber layer.

[0020] The surface fiber layer may contain synthetic fibers to improve mechanical properties such as tensile strength and flame retardancy. When the fiber layer contains synthetic fibers, the synthetic fiber content is preferably 25% by mass or more and 50% by mass or less relative to the total mass of fibers contained in the surface fiber layer. A synthetic fiber content of 25% by mass or more fully demonstrates the benefits of incorporating synthetic fibers. A synthetic fiber content of 50% by mass or less ensures a sufficiently high proportion of plant fibers, thereby reducing the environmental impact during production and disposal. Furthermore, the high thermal conductivity of plant fibers provides a pleasant feel. Furthermore, by incorporating synthetic fibers with different dyeability than plant fibers, the surface fiber layer can achieve excellent melange-like designs due to the difference in dyeability. Examples of synthetic fibers that may be contained in the surface fiber layer include polyester, nylon 6, nylon 66, acrylic, polyurethane, and polylactic acid fibers.

[0021] [Base material] The content of plant fibers in the substrate contained in the artificial leather of this embodiment is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 80% by mass or more, based on the total mass of the substrate. A content of 50% by mass or more reduces the environmental impact during production and disposal, and the high thermal conductivity of the plant fibers provides a good feel. The substrate can contain fibers other than plant fibers, preferably in an amount of 50% by mass or less relative to the total mass of the substrate, for the purpose of improving mechanical properties such as tensile strength and flame retardancy. When the substrate contains fibers other than plant fibers, for example, synthetic fibers such as polyester, nylon 6, nylon 66, acrylic, polyurethane, and polylactic acid; semi-synthetic fibers such as acetate, triacetate, and promix; recycled fibers such as rayon, cupra, and lyocell; and inorganic fibers such as glass fiber and carbon fiber can be used. In particular, from the viewpoint of mechanical properties, the use of synthetic fibers is preferred.

[0022] The substrate is not particularly limited as long as it is a fiber fabric, and can be, for example, a woven fabric, a knitted fabric, a nonwoven fabric, or the like. The fibers constituting the substrate may be of either a single type or multiple types. For example, the substrate may be a woven or knitted fabric using a composite spun yarn of different materials spun from multiple types of staple fibers, or a woven or knitted fabric using multiple types of spun yarns or filament yarns made from different materials. From the viewpoint of ensuring a peel strength of 2 N / cm or more between the surface fiber layer and the substrate, the substrate is preferably a woven fabric.

[0023] When the substrate is a woven fabric, the woven fabric may have a structure represented by the following formula:

number

[0024] [Binder resin] The artificial leather of this embodiment may contain a binder resin in order to further increase the entanglement strength between fibers. On the other hand, if the artificial leather does not contain a binder resin, it has the advantage of being able to achieve extremely high conformability to the shape of automobile interiors, furniture, etc. Therefore, whether or not to contain a binder resin can be appropriately selected depending on the properties required for each application.

[0025] When the artificial leather contains a binder resin, the binder resin content is preferably more than 0% by mass and not more than 20% by mass, more preferably more than 0% by mass and not more than 15% by mass, relative to the total mass of the artificial leather. If the binder resin content is 20% by mass or less, mechanical properties such as abrasion resistance and tensile strength are improved, while the artificial leather has sufficiently high flexibility, resulting in a good texture and good conformability to complex shapes such as automobile interiors and furniture. Furthermore, from the viewpoint of strengthening the bond strength between the fibers constituting the surface fiber layer, the binder resin content is preferably 5% by mass or more, more preferably 8% by mass or more.

[0026] The type of binder resin is not particularly limited, but examples thereof include acrylic resin, urethane resin, polyester resin, vinyl acetate resin, etc. From the viewpoint of achieving both flexibility and durability, the binder resin is preferably a urethane resin, and particularly from the viewpoint of reducing the environmental load, a water-dispersible urethane resin is preferred.

[0027] [Other preferred embodiments of artificial leather] In order to impart a smooth feel like suede or nubuck to the artificial leather of this embodiment, the height Sz of the surface irregularities is preferably 200 μm or more and 600 μm or less, more preferably 500 μm or less, and even more preferably 450 μm or less. When Sz is 200 μm or more, the surface has moderate irregularities, resulting in a soft feel. On the other hand, when Sz is 600 μm or less, the surface is less likely to feel rough.

[0028] To achieve Sz of 200 μm or more and 600 μm or less, it is preferable that the surface is napped, and Sz can be appropriately adjusted by adjusting the nap-raising conditions, etc. Sz can also be adjusted by adjusting the types of staple fibers and spun yarns used in the surface fiber layer and the substrate, the length, thickness, and twist number of single fibers, the basis weight, thickness, and density of the surface fiber layer and the substrate, the type and amount of binder resin applied, the processing conditions in the entanglement step, etc.

[0029] The artificial leather of the present embodiment is preferably dyed. As a dyeing method, dyeing treatment using a jet dyeing machine is preferred from the viewpoint of improving texture.

[0030] The artificial leather of this embodiment can have a resin layer formed on its surface to improve abrasion resistance and flame retardancy. Furthermore, by mixing a pigment into the resin layer, it is possible to color the leather. The method for forming the resin layer is not particularly limited, and examples include a method of forming a resin layer by applying a resin solution in which a resin is dissolved in a solvent and then drying the solvent, a method of forming a resin layer by applying a resin solution and then reacting the resin (dry method), a method of attaching a resin film made of a synthetic resin (lamination method), and a method of applying a resin solution and then introducing it into a coagulation bath to coagulate it (wet method).

[0031] [Skin materials for vehicle interiors] Another embodiment of the present invention is a vehicle interior covering material including the above-mentioned artificial leather. The vehicle interior covering material of this embodiment can be suitably used as a covering material to be attached to seats, door trims, instrument panels, ceilings, etc.

[0032] The vehicle interior skin material of this embodiment may have a urethane foam laminated on the back surface to provide cushioning, and may be embossed or embroidered for design and functionality. [Example]

[0033] EXAMPLES The present invention will be specifically explained below with reference to Examples and Comparative Examples, but the present invention is not limited to the Examples alone. The methods for measuring various physical properties of the artificial leathers used in the following examples are as follows.

[0034] (a) Peel strength between fiber layer and substrate (N / cm) Two rectangular samples (referred to as Samples A and B) with short sides of 2.5 cm and long sides of 10 cm were cut from the artificial leather so that the long sides were perpendicular to each other. The entire surface of both samples (the raised side in the case of raised artificial leather) was coated with 50 mg / cm of synthetic rubber adhesive ThreeBond 1521 (manufactured by ThreeBond Co., Ltd.). 2 The adhesive was applied at a coating weight of 100g. Immediately after application, the adhesive-coated surfaces of two samples were bonded together, with their long and short edges aligned. The bonded samples were compressed at 0.4 MPa using a mangle and then left at 20°C and 50% RH for at least 5 hours. The bonded samples were cut off 2.5mm from each end of the short edge with scissors to a size of 2.0cm (width) x 10cm (length). A razor blade was used to make a slit at the boundary between the substrate and surface fiber layer of sample A along the short edge, and the substrate and surface fiber layer were then peeled off approximately 2cm using fingers. Next, using an A&D Tensilon Universal Testing Machine (Model RTC-1210A), the substrate and surface fiber layer were gripped with a 2cm gripping length and pulled at a crosshead speed of 100mm / min and a paper speed of 50mm / min to separate the substrate and surface fiber layer, and the stress at this time was measured. Of the multiple peaks in the obtained stress-displacement chart, the peak values of the three largest peaks in order from the largest peak and the three smallest peaks in order from the smallest peak were read, and the average of the six points was calculated. Using the bonded sample, a similar cut was made at the boundary between the substrate and the surface fiber layer of sample B, and the same measurement was carried out again. The average of the two results obtained was divided by the sample width (2 cm) to determine the peel strength.

[0035] (b) Cover Factor CF The cover factor CF is calculated using the following formula:

number

[0036] (c) The specific surface area (m) of the plant fibers used as the raw material for the surface fiber layer and the fibers contained in the surface fiber layer 2 / g) The specific surface area was measured using an automatic specific surface area measuring device (Shimadzu Corporation, Gemini 2360). The sample mass used for the measurement was 0.20 to 0.60 g. The cell containing the sample was dried at 60°C for 30 minutes and then cooled for 10 minutes. Thereafter, the cell was set in the specific surface area measuring device, and the following BET equation was calculated by nitrogen gas adsorption onto the sample surface: P / {V(P0-P)}=1 / (Vm×C)+{(C-1) / (Vm×C)}(P / P0) The specific surface area was calculated using the formula: {where P: pressure, P0: saturated water vapor pressure (Pa), V: nitrogen adsorption amount (mg / g), Vm: monolayer adsorption amount (mg / g), and C: parameter related to heat of adsorption etc. (-)<0.} The measurement samples were prepared as follows.

[0037] <Plant fibers used as raw material for the surface fiber layer> The procedure of centrifugation, removal of the supernatant, and dilution with ethanol was repeated three times using the aqueous dispersion of plant fiber. Next, the procedure of centrifugation, removal of the supernatant, and dilution with t-butanol was repeated twice using the ethanol dispersion of plant fiber obtained above. Next, the t-butanol dispersion of plant fiber obtained above was centrifuged, the supernatant was removed, a small amount of t-butanol was added, and the mixture was freeze-dried to prepare a sample for measurement. <Fibers in the surface fiber layer> The surface fiber layer was peeled off from the artificial leather, and if the surface fiber layer had a binder resin and / or a surface resin layer, the binder resin and / or the surface resin layer was dissolved and removed using a solvent that could dissolve the binder resin and / or the surface resin layer but not the fibers, to prepare a sample for measurement.

[0038] (d) Height of the surface irregularities of the artificial leather (Sz) Using a one-shot microscope (Keyence Corporation VR-3200), a 15cm square sample of artificial leather is observed and photographed at 40x magnification. To eliminate irregularities not originating from the surface fiber layer, the entire measurement range is specified and surface shape correction (quadratic surface correction) is performed on the photographed data. Then, "Surface Roughness Measurement" on the analysis screen is performed, specifying the entire measurement range as the measurement range and setting the filter to low-pass filter: none, high-pass filter: none, to obtain the maximum height Sz. Ten measurements are performed on different measurement locations on the sampled artificial leather, and the average value is used as the result. In this measurement, if the artificial leather surface has deformations due to embossing, embroidery, etc., measurements are taken at 10 locations excluding the deformed areas.

[0039] (e) Abrasion resistance JIS-L-1096 (2015 edition) 8.19 "Abrasion resistance" (E method: Martindale The abrasion resistance test of the surface fiber layer of the artificial leather was carried out under a pressure load (12 kPa) according to the method. The relationship between the number of abrasions and the exposed state of the substrate was judged according to the following evaluation criteria, with ◯ and ⊚ representing pass. ×: The substrate is exposed after 30,000 times. △: The substrate is not exposed after 30,000 times, but the scrim is exposed after 40,000 times. ○: The substrate is not exposed after 40,000 times, but the scrim is exposed after 50,000 times. ◎: The substrate is not exposed after 50,000 times.

[0040] (f)Flexibility A 25cm square sample of artificial leather was placed in a room at 20°C and 65% humidity for at least 10 hours to condition the humidity. After that, the softness of the sample was evaluated by rating it according to the following criteria, based on how it felt when handled in the same room. Ratings were made in 0.5 grade increments. Grade 5: Fairly flexible Level 4: Flexible Grade 3: Somewhat flexible Grade 2: Slightly hard Grade 1: Quite hard

[0041] (g)Tactile sensation A 25cm square sample of artificial leather was placed in a room at 20°C and 65% humidity for at least 10 hours to condition the humidity. After that, the surface of the sample was run over with a bare hand in the same room, and the feel was assessed by rating it according to the following criteria. Ratings were made in 0.5 grade increments. Grade 5: Very good feel Grade 4: Fairly good feel Grade 3: Good touch Grade 2: Slightly poor texture Grade 1: Poor touch

[0042] [Example 1] Fibrillated, specific surface area 0.67m 2 Cotton staple fibers with a fiber length of 3 mm and a fiber diameter of 4 μm were mixed in a mass ratio of 70:30 and dispersed in water to prepare a slurry for the surface fiber layer. A woven fabric made of 20-count cotton / PET (65 / 35) spun yarn with a warp density of 55 threads / 2.54 cm and a weft density of 60 threads / 2.54 cm was used as the substrate, and a 140 g / m2 fabric was applied to one side of the substrate (hereinafter referred to as the "surface layer"). 2 The opposite side (hereinafter referred to as the "back layer") has a basis weight of 60 g / m 2 The slurry was used to deposit short fibers by papermaking, and a three-layer laminated nonwoven fabric sheet was continuously produced. Next, a water jet was sprayed from the front layer at a pressure of 4.0 MPa and from the back layer at a pressure of 3.0 MPa using a straight-flow spray nozzle with a hole diameter of 0.1 mm to perform an entanglement treatment, and the sheet was dried with a pin tenter to obtain a sheet with a basis weight of 330 g / m. 2The surface of this sheet was buffed with #400 sandpaper, and then the sheet was impregnated with an aqueous dispersion of 9% by mass of a polyether-based water-based polyurethane resin and 3% by mass of Glauber's salt so that the adhesion rate of the polyurethane resin was 14.3% by mass relative to the mass of the sheet after impregnation, and the sheet was heated and dried for 3 minutes in a pin tenter dryer to produce a raw fabric of artificial leather. This raw fabric was dyed black in a jet dyeing machine to produce a suede-like artificial leather.

[0043] [Example 2] Instead of short cotton fibers, a specific surface area of 0.53 m 2 An artificial leather was produced in the same manner as in Example 1, except that pineapple staple fibers having a fiber count of 1 / g and an L / D value of 250 were used, a woven fabric consisting of 20 count pineapple fiber / PET (45 / 55) spun yarn with a warp density of 55 threads / 2.54 cm and a weft density of 60 threads / 2.54 cm was used as the substrate, and the sheet was impregnated so that the adhesion rate of the polyurethane resin was 4.1% by mass of the sheet mass after impregnation.

[0044] [Example 3] Specific surface area 0.67m 2 / g, and L / D value of 250, instead of cotton short fiber, specific surface area of 1.42 m 2 An artificial leather was produced in the same manner as in Example 1, except that short cotton fibers having a tensile strength of 1000 kJ / g and an L / D value of 250 were used and that the fibers were not impregnated with the aqueous dispersion of the water-based polyurethane resin.

[0045] [Example 4] In the production of nonwoven fabric sheets, the surface layer has a basis weight of 100 g / m 2 , and the back layer has a basis weight of 35 g / m 2 An artificial leather was produced in the same manner as in Example 1, except that the sheet was made to have a density of 23.6% by mass, and that a solvent-based polyurethane resin was used instead of the aqueous polyurethane resin, and the sheet was impregnated with the polyurethane resin at a density of 23.6% by mass.

[0046] [Example 5] Specific surface area 0.67m 2 / g, and L / D value of 250, instead of cotton short fiber, specific surface area of 0.30 m 2 An artificial leather was produced in the same manner as in Example 1, except that short cotton fibers having a tensile strength of 1.0 ...

[0047] [Example 6] Instead of short cotton fibers, a specific surface area of 0.58 m 2 An artificial leather was produced in the same manner as in Example 1, except that wool short fibers having a tensile strength of 1.000 MPa and an L / D value of 2,500 were used.

[0048] [Example 7] As a slurry, the specific surface area is 0.67m 2 An artificial leather was produced in the same manner as in Example 1, except that a slurry was used in which only cotton staple fibers having a fiber density of 48 / g and an L / D value of 250 were dispersed in water, and that the substrate was a woven fabric made of 30 count cotton spun yarn with a warp density of 48 threads / 2.54 cm and a weft density of 50 threads / 2.54 cm.

[0049] [Example 8] An artificial leather was produced in the same manner as in Example 1, except that the mixing ratio of cotton staple fibers to polyester staple fibers in the slurry was 35:65, and the substrate was a woven fabric made of 20-count cotton spun yarn with a warp density of 55 threads / 2.54 cm and a weft density of 60 threads / 2.54 cm.

[0050] [Example 9] An artificial leather was produced in the same manner as in Example 1, except that the base material was a woven fabric made of 30-count cotton / PET (65 / 35) spun yarn with a warp density of 35 threads / 2.54 cm and a weft density of 40 threads / 2.54 cm.

[0051] [Example 10] The sheet was impregnated so that the adhesion rate of polyurethane resin was 6.6% by mass relative to the sheet mass, and instead of dyeing the raw sheet, 25 g / m of water-dispersed polyurethane resin containing a pigment was applied to the surface of the raw sheet using a knife coater. 2An artificial leather was produced in the same manner as in Example 1, except that the coating amount was 1000 mg / L.

[0052] [Example 11] Specific surface area 0.67m 2 / g of cotton short fiber, and 2 An artificial leather was produced in the same manner as in Example 1, except that short cotton fibers having a fiber content of 10 ...

[0053] [Example 12] Specific surface area 0.67m 2 / g of cotton short fiber, 2 An artificial leather was produced in the same manner as in Example 1, except that short cotton fibers having a fiber content of 10 ...

[0054] [Example 13] Specific surface area 0.67m 2 / g of cotton short fiber, and 2 An artificial leather was produced in the same manner as in Example 1, except that short cotton fibers having a fiber content of 10 ...

[0055] [Example 14] An artificial leather was produced in the same manner as in Example 1, except that cotton staple fibers having an L / D value of 80 were used instead of the cotton staple fibers having an L / D value of 250.

[0056] [Comparative Example 1] Using the same slurry as in Example 1, a basis weight of 200 g / m 2A single-layer nonwoven fabric sheet was continuously produced by papermaking so that the thickness of the nonwoven fabric sheet was as follows. Next, a water jet was sprayed from the front layer at a pressure of 4.0 MPa and from the back layer at a pressure of 3.0 MPa using a straight-flow spray nozzle with a hole diameter of 0.1 mm to perform an entanglement treatment, and the sheet was dried in a pin tenter to produce a sheet. The front layer of this sheet was buffed with #400 sandpaper, and then the sheet was impregnated with a solvent-based polyurethane resin solution so that the adhesion rate of the polyurethane resin was 40% by mass relative to the mass of the sheet after impregnation, and the sheet was heated and dried for 3 minutes in a pin tenter dryer to produce an artificial leather raw material. A pigment-containing solvent-based polyurethane resin was applied to the surface of the front layer of this raw material using a knife coater at a rate of 25 g / m. 2 The coating amount was applied to the surface to produce an artificial leather.

[0057] Comparative Example 2 An artificial leather was produced in the same manner as in Comparative Example 1, except that the adhesion rate of the solvent-based polyurethane was set to 4.8 mass% of the sheet mass after impregnation, and that instead of applying a pigment-containing solvent-based polyurethane resin to the surface, the raw fabric was dyed black using a liquid jet dyeing machine.

[0058] Comparative Example 3 An artificial leather was produced in the same manner as in Example 1, except that the mixing ratio of cotton staple fibers to polyester staple fibers in the slurry was 35:65, and a woven fabric made of 20 count polyester spun yarn with a warp density of 55 threads / 2.54 cm and a weft density of 60 threads / 2.54 cm was used as the base material.

[0059] The various physical properties and evaluation results of the artificial leathers produced in the above Examples and Comparative Examples are shown in Tables 1 to 3 below.

[0060] [Table 1]

[0061] [Table 2]

[0062] [Table 3] [Industrial Applicability]

[0063] The present invention relates to an artificial leather that contains a large amount of plant fibers and combines softness with abrasion resistance, and therefore can be used in a wide range of applications, such as furniture, clothing, the automotive industry, shoes, and bags, and is particularly suitable for use as a skin material for vehicle interiors.

Claims

1. An artificial leather comprising a substrate made of a fiber cloth and a surface fiber layer laminated on the substrate, the artificial leather having the following characteristics (1) to (3): (1) Both the substrate and the surface fiber layer contain plant fibers; (2) The content of plant fibers in the artificial leather is 50% by mass or more relative to the total mass of the artificial leather; and (3) The peel strength between the substrate and the surface fiber layer is 2 N / cm or more; Artificial leather that satisfies the above.

2. 2. The artificial leather according to claim 1, wherein the content of the plant fibers in the substrate is 50% by mass or more with respect to the total mass of the substrate.

3. The artificial leather according to claim 1 or 2, which contains a binder resin.

4. The artificial leather according to claim 3 , wherein the content of the binder resin is more than 0% by mass and 20% by mass or more with respect to the total mass of the artificial leather.

5. The artificial leather according to claim 3 , wherein the binder resin is a polyurethane resin.

6. 6. The artificial leather according to claim 5, wherein the polyurethane resin is a water-dispersible polyurethane resin.

7. 3. The artificial leather according to claim 1, wherein the L / D value, which is the ratio of fiber length L to single fiber diameter D of the vegetable fibers contained in the surface fiber layer, is 50 or more and 4,000 or less.

8. The artificial leather according to claim 1 or 2, wherein the surface fiber layer contains cellulose fibrils.

9. The specific surface area of the fibers constituting the surface fiber layer is 0.10 m ２ The artificial leather according to claim 1 or 2, wherein the elastic modulus is 1 / g or more.

10. Further features below (4): (4) The surface fiber layer has a specific surface area of 0.5 m ２ / g or more 1.5m ２ / g or less of cellulose fibrils; 3. The artificial leather according to claim 1, wherein the above-mentioned condition is satisfied.

11. The artificial leather according to claim 1 or 2, wherein the surface fiber layer comprises synthetic fibers.

12. The artificial leather according to claim 11, wherein the content of the synthetic fibers in the surface fiber layer is 25% by mass or more and 50% by mass or less with respect to the total mass of the fibers contained in the surface fiber layer.

13. The artificial leather according to claim 1 or 2, wherein the substrate is a woven fabric.

14. 14. The artificial leather according to claim 13, wherein the cover factor CF of the woven fabric is 15 or more and 40 or less.

15. 3. The artificial leather according to claim 1, wherein the height Sz of the surface irregularities of the artificial leather is 200 μm or more and 600 μm or less.

16. 3. The artificial leather according to claim 1, wherein the surface of the artificial leather is napped.

17. The artificial leather according to claim 1 or 2, wherein the artificial leather is dyed.

18. A skin material for vehicle interiors, comprising the artificial leather according to claim 1 or 2.

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