Leather-like sheet

Abstract

To provide a leather-like sheet excellent in both of optical transparency and designability (hyperchromic effect, concealability).SOLUTION: The leather-like sheet according to an embodiment comprises at least one colored skin layer, with an uneven pattern on the outermost surface. The outermost surface has an arithmetic average curvature (Spc) of peaks of 100 or more and a developed area ratio (Sdr) of an interface of 0.15 or more. The leather-like sheet has a light transmittance of 0.25 to 15%.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a leather-like sheet. [Background technology]

[0002] In recent years, in order to respond to the differentiation of products and the diversification of consumer tastes, there has been a demand for materials with novel designs for decorating the surfaces of articles. As such a material, a technology has been proposed in which a lighting device such as a backlight is placed on the back of a colored sheet to emit light and transmit the light, thereby making letters, patterns, etc. stand out on the surface of the sheet.

[0003] Patent Document 1 discloses a skin material having a transmission density in the range of 0.5 to 4.2 as measured in accordance with ISO 5-2 (2009). It is disclosed that this provides a skin material that achieves both light transmittance and the ability of the skin material to conceal the substrate, allowing for high design freedom.

[0004] Patent Document 2 discloses synthetic leather in which a surface layer made of polyurethane resin is laminated on raw cloth, and the visible light transmittance in the wavelength range of 380 to 780 nm is 0.10 to 11.90%. It is disclosed that this provides synthetic leather that has excellent texture and feel and can be mass-produced without requiring skill. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-147741 [Patent Document 2] JP 2013-177714 A Summary of the Invention [Problem to be solved by the invention]

[0006] In the skin materials of Patent Documents 1 and 2, the desired light transmittance is obtained by adjusting the content of the colorant in the skin layer and the thickness of the skin layer. Therefore, there is still room for improvement in terms of achieving both light transmittance and design (for example, expressing a dark color design without reducing light transmittance).

[0007] The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a leather-like sheet that combines light transmittance and design properties (dark color effect, hiding power). [Means for solving the problem]

[0008] The present invention includes the embodiments set forth below. [1] A leather-like sheet consisting of at least one colored skin layer and having an uneven pattern on its outermost surface, wherein the arithmetic mean curvature (Spc) of the peaks of the outermost surface is 100 or more and the developed area ratio (Sdr) of the interface at the outermost surface is 0.15 or more, and the light transmittance of the leather-like sheet is 0.25 to 15%. [2] L * a * b * The L of the leather-like sheet in the color system * Value is 30 or less, a * value and b * The leather-like sheet according to [1], wherein both of the values ​​are -1.0 or more and 1.0 or less, the colored surface layer contains 0.5 to 1.3 mass % of an inorganic pigment, and the leather-like sheet has a light transmittance of 0.25 to 2.5%. [3] L * a * b * The L of the leather-like sheet in the color system * Value is 30 or less, a * value and b * The leather-like sheet according to [1], wherein both of the values ​​are -1.0 or more and 1.0 or less, the colored surface layer contains 5 to 7.5 mass % of only organic pigments, and the light transmittance of the leather-like sheet is 0.25 to 5%. [4] L * a * b * The L of the leather-like sheet in the color system *The leather-like sheet according to [1], wherein the colored surface layer contains 5 to 15 mass % of an inorganic pigment and / or an organic pigment, and the leather-like sheet has a light transmittance of 2.5 to 15%. Effect of the Invention

[0009] According to an embodiment of the present invention, it is possible to provide a leather-like sheet that combines light transmission and design properties (dark color effect, hiding power). [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view of a leather-like sheet according to an embodiment. FIG. [Diagram 2] FIG. 4 is a schematic cross-sectional view of a leather-like sheet according to another embodiment. [Diagram 3] FIG. 4 is a schematic cross-sectional view of a leather-like sheet according to another embodiment. [Figure 4] 2 shows the complete structure of the fabric used in Example 27. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The leather-like sheet according to the present embodiment is composed of at least one colored skin layer and has an uneven pattern on the outermost surface. The "outermost surface" of the leather-like sheet refers to the surface (design surface) that is visible when in use, among the front and back surfaces of the leather-like sheet.

[0012] The leather-like sheet according to this embodiment has an arithmetic mean curvature (Spc) of the peaks of the outermost surface of 100 or more, and an interface developed area ratio (Sdr) of the outermost surface of 0.15 or more. By satisfying the above, light is less likely to be reflected and more likely to be absorbed on the surface of the leather-like sheet, resulting in a deep color effect and good design. Spc is preferably 110 or more, more preferably 120 or more. Sdr is preferably 0.20 or more, more preferably 0.25 or more.

[0013] The arithmetic mean curvature of the peak (Spc) represents the arithmetic mean of the principal curvatures of the peaks in the defined area. The smaller the value, the more rounded the point of contact with other objects is, and the larger the value, the more pointed the point of contact with other objects is. When the Spc is 100 or more, the convex parts of the uneven pattern are sharp, making it difficult to reflect light and easy to absorb it. Therefore, it is easy to achieve a deep color effect. The method of determining Spc will be described later. In this specification, the "defined area" refers to the area of ​​the test piece (the area defined within the image area where the test piece is observed), and is 2000 μm long x 2000 μm wide.

[0014] The developed area ratio (Sdr) of the interface at the outermost surface indicates how much the developed area (surface area) of the defined area has increased relative to the area of ​​the defined area. The Sdr of a completely flat surface is "0". An Sdr of "0.15" means that the surface area has increased by 15%. By increasing the developed area (surface area) per defined area, light is less likely to be reflected and more likely to be absorbed. This makes it easier to achieve a deep color effect. The method of calculating Sdr will be described later. In this specification, the "defined area" refers to the area of ​​the test piece (the area defined within the image area where the test piece is observed), which is 2000 μm long x 2000 μm wide.

[0015] The leather-like sheet according to the present embodiment has a light transmittance of 0.25 to 15%. With a light transmittance of 0.25% or more, when light is irradiated from the back side of the leather-like sheet, the light can be visually recognized from the front side of the leather-like sheet. With a light transmittance of 15% or less, the concealing property of the leather-like sheet can be improved. If the light transmittance is within the above numerical range, the leather-like sheet has light transmittance and concealing property. For example, in a mode in which a substrate is laminated, the substrate does not show through from the front side of the leather-like sheet, and good design is easily obtained. The method of determining the light transmittance will be described later.

[0016] The light transmittance may be appropriately adjusted within the above range depending on the color of the leather-like sheet and taking into consideration the hiding power. For example, L * a * b *L of leather-like sheet material in color system * Value is 30 or less, a * value and b * When both values ​​are −1.0 or more and 1.0 or less, and the colored skin layer contains an inorganic pigment, the light transmittance is preferably 0.25 to 2.5%. L * a * b * L of leather-like sheet material in color system * Value is 30 or less, a * value and b * When both values ​​are −1.0 or more and 1.0 or less, and the colored skin layer contains only organic pigments, the light transmittance is preferably 0.25 to 5%. L * a * b * L of leather-like sheet material in color system * When the value is 35 or more and the colored skin layer contains an inorganic pigment and / or an organic pigment, the light transmittance is preferably 2.5 to 15%. By ensuring that each of the above-mentioned ratios is equal to or greater than the lower limit, the light transmittance can be improved, whereas by ensuring that each of the above-mentioned ratios is equal to or less than the upper limit, the design, particularly the hiding power, can be improved.

[0017] The leather-like sheet according to the present embodiment is not particularly limited in its layer structure, so long as it has an uneven pattern on its outermost surface, an arithmetic mean curvature (Spc) of the peaks of the outermost surface of 100 or more, an interface developed area ratio (Sdr) of the outermost surface of 0.15 or more, and a light transmittance of 0.25 to 15%. In other words, an additional resin layer or fibrous base material may be provided within a range that does not impair the effect of the present embodiment.

[0018] 1 is a cross-sectional view showing a schematic diagram of a leather-like sheet 1 according to one embodiment. This leather-like sheet 1 is made of a colored skin layer 11. The surface of the colored skin layer 11 is provided with an uneven pattern 2.

[0019] 2 is a cross-sectional view showing a leather-like sheet 10 according to another embodiment. In this leather-like sheet 10, an adhesive layer 13, a colored skin layer 11, and a protective layer 14 are laminated in this order on one surface of a fibrous base material 12. The surface of the protective layer 14 is provided with an uneven pattern 2.

[0020] Fig. 3 is a cross-sectional view showing a leather-like sheet 100 according to another embodiment. This leather-like sheet 100 differs from the leather-like sheet 10 in Fig. 2 in that an anchor coat layer 15 and a heat insulating layer 16 are provided on an adhesive layer 13. Thus, in the example of Fig. 3, the adhesive layer 13, the anchor coat layer 15, the heat insulating layer 16, the colored skin layer 11, and the protective layer 14 are laminated in this order on one side of the fibrous base material 12. The surface of the protective layer 14 is provided with an uneven pattern 2.

[0021] In the examples of Figures 1 to 3, the outermost surface of the leather-like sheet is provided with an uneven pattern 2. Here, the "outermost surface" of the leather-like sheet refers to the surface (design surface) that is visible when in use among the front and back surfaces of the leather-like sheet, and is the surface of the colored skin layer or protective layer.

[0022] The colored skin layer used in this embodiment preferably contains a resin. Examples of the resin constituting the colored skin layer include conventionally known resins such as polyurethane resin, acrylic resin, polyester resin, polyvinyl chloride resin, etc., and these can be used alone or in combination of two or more. Among them, polyurethane resin is preferable from the viewpoint of versatility.

[0023] The polyurethane resin is not particularly limited, and examples thereof include polycarbonate-based urethane resins, polyether-based polyurethane resins, etc. Among them, polycarbonate-based polyurethane resins are preferred from the viewpoint of durability, and non-yellowing polycarbonate-based polyurethane resins and resistant to yellowing polycarbonate-based polyurethane resins are more preferred from the viewpoint of less discoloration and less effect on light transmittance.

[0024] Various additives such as pigments, dyes, crosslinking agents, catalysts, etc. may be added to the resins as long as they do not impair the effects of the present embodiment, and these may be used alone or in combination of two or more. Among them, from the viewpoint of the design of the leather-like sheet (dark color effect, hiding power), it is preferable to add pigments and dyes. From the viewpoint of versatility, pigments are preferable.

[0025] The pigment is not particularly limited, and examples thereof include inorganic pigments and organic pigments, which can be used alone or in combination of two or more. Among them, it is preferable to use an organic pigment, from the viewpoint of being less likely to reflect and absorb light.

[0026] The content (solid content ratio) of the pigment or dye in the colored skin layer may be appropriately adjusted in consideration of light transmittance and hiding power according to the color of the leather-like sheet and the pigment or dye used. For example, L * a * b * L of leather-like sheet material in color system * Value is 30 or less, a * value and b * When both values ​​are −1.0 or more and 1.0 or less, and the colored skin layer contains an inorganic pigment, the content of the inorganic pigment in the colored skin layer is preferably 0.5 to 1.3 mass %. L * a * b * L of leather-like sheet material in color system * Value is 30 or less, a * value and b * When both values ​​are −1.0 or more and 1.0 or less and the colored skin layer contains only an organic pigment, the content of the organic pigment in the colored skin layer is preferably 5 to 7.5 mass %. L * a * b * L of leather-like sheet material in color system * When the value is 35 or more and the colored skin layer contains an inorganic pigment and / or an organic pigment, the content of the inorganic pigment and / or the organic pigment in the colored skin layer is preferably 5 to 15 mass %. By ensuring that each of the above-mentioned ratios is equal to or greater than the lower limit, the design, particularly the hiding power, can be improved, whereas by ensuring that each of the above-mentioned ratios is equal to or less than the upper limit, the light transmittance can be improved.

[0027] In this specification, the solid content refers to components other than volatile substances such as organic solvents and water, and is also called evaporation residue or non-volatile content. Therefore, liquids that do not evaporate at normal drying temperatures, such as plasticizers, are also included in the solid content.

[0028] The thickness of the colored skin layer is not particularly limited, but is preferably 30 to 45 μm, and more preferably 35 to 40 μm. By making the thickness equal to or greater than the lower limit, the design, particularly the hiding power, can be improved. By making the thickness equal to or less than the upper limit, the light transmittance can be improved.

[0029] The leather-like sheet of the present embodiment may have a fibrous substrate. The fibrous substrate is not particularly limited, and examples thereof include fibrous fabrics such as knitted fabrics, woven fabrics, and nonwoven fabrics.

[0030] The type of fiber in the fiber fabric is not particularly limited, and examples thereof include conventionally known fibers such as natural fibers, regenerated fibers, semi-synthetic fibers, and synthetic fibers, and two or more of these may be combined. Among these, from the viewpoints of strength and processability, synthetic fibers are preferred as the fibers, and polyester fibers are more preferred.

[0031] The shape of the fiber is not particularly limited, and may be either long fiber or short fiber. The form of the yarn constituting the fibrous substrate may be short fiber yarn such as spun yarn, long fiber yarn such as multifilament yarn or monofilament yarn, or long and short composite spun yarn combining long fiber and short fiber. As the yarn, a short fiber previously subjected to crimping may be used, or the yarn may be subjected to processing such as false twisting or fluid disturbance treatment.

[0032] The fibrous base material may be colored with a dye or pigment. From the viewpoint of light transmittance, it is preferable that the fibrous base material is not colored.

[0033] The basis weight of the fibrous substrate may be appropriately set in consideration of the light transmittance and durability of the leather-like sheet. The basis weight of the fibrous substrate is not particularly limited, and is, for example, 100 to 400 g / m 2 It is preferable that:

[0034] When the leather-like sheet of this embodiment has a fibrous substrate, an adhesive layer may be interposed between the fibrous substrate and the colored skin layer, or a colored skin material may be directly laminated to the fibrous substrate. By interposing an adhesive layer between the fibrous substrate and the colored skin layer, the adhesion between the fibrous substrate and the colored skin layer can be improved. The adhesive layer may be a non-foamed resin layer without bubbles, or a foamed resin layer with bubbles.

[0035] The resin constituting the adhesive layer may be the same as that used for the colored skin layer, and from the viewpoint of durability, a polycarbonate-based polyurethane resin is preferred as the polyurethane resin for the adhesive layer.

[0036] The adhesive layer may be colored with the same dye or pigment as the colored skin layer, but from the viewpoint of light transmission, it is preferable that the adhesive layer is not colored.

[0037] The adhesive layer resin composition liquid used to form the adhesive layer can contain optional components as necessary within the range that does not impair the physical properties of the polyurethane resin. Examples of optional components include crosslinking agents, flame retardants, catalysts, etc. These can be used alone or in combination of two or more.

[0038] The thickness of the adhesive layer is not particularly limited, and is preferably, for example, 100 to 200 μm. By making the thickness equal to or greater than the lower limit, the light transmittance can be improved. By making the thickness equal to or less than the upper limit, the concealing properties and texture can be improved.

[0039] In this embodiment, when the adhesive layer is provided, an anchor coat layer and a heat insulating layer may be interposed between the adhesive layer and the colored skin layer. By interposing the anchor coat layer between the adhesive layer and the colored skin layer, the abrasion resistance of the resulting leather-like sheet can be improved. By interposing the heat insulating layer, the heat insulating property of the resulting leather-like sheet can be improved.

[0040] The resin constituting the anchor coat layer may be the same as that of the colored surface layer. Among them, from the viewpoint of abrasion resistance, a polycarbonate-based polyurethane resin is preferable as the polyurethane resin for the anchor coat layer.

[0041] The anchor coat layer may be colored with the same dye or pigment as the colored skin layer, but from the viewpoint of light transmittance, it is preferable that the anchor coat layer is not colored.

[0042] The resin composition liquid for the anchor coat layer used to form the anchor coat layer can contain optional components as necessary within the range that does not impair the physical properties of the polyurethane resin. Optional components include, for example, crosslinking agents, flame retardants, defoamers, catalysts, viscosity adjusters, etc. These can be used alone or in combination of two or more.

[0043] The thickness of the anchor coat layer is not particularly limited, and is preferably, for example, 17 to 27 μm. By making the thickness equal to or greater than the lower limit, it is possible to improve abrasion resistance. By making the thickness equal to or less than the upper limit, it is possible to improve light transmittance.

[0044] The resin constituting the heat insulating layer may be the same as that used for the colored skin layer, and among these, from the viewpoint of durability, a polycarbonate-based polyurethane resin is preferred as the polyurethane resin for the heat insulating layer.

[0045] The heat insulating layer may be colored with the same dye or pigment as the colored skin layer, but from the viewpoint of light transmittance, it is preferable that the heat insulating layer is not colored.

[0046] The resin composition liquid for the heat insulating layer used to form the heat insulating layer can contain optional components as necessary within the range that does not impair the physical properties of the polyurethane resin. Examples of optional components include crosslinking agents, flame retardants, catalysts, foaming agents, antifoaming agents, hollow fine particles, etc. These can be used alone or in combination of two or more.

[0047] The thickness of the heat insulating layer is not particularly limited, and is preferably, for example, 70 to 170 μm. By making the thickness equal to or greater than the lower limit, durability can be improved. By making the thickness equal to or less than the upper limit, deterioration in texture due to roughness and hardness can be prevented.

[0048] In the present embodiment, a protective layer may be provided on the colored skin layer. By providing a protective layer on the colored skin layer, the abrasion resistance of the resulting leather-like sheet can be improved.

[0049] The resin constituting the protective layer may be the same as that of the colored skin layer. Among them, from the viewpoint of abrasion resistance, the polyurethane resin for the protective layer is preferably a polycarbonate-based polyurethane resin, more preferably a non-yellowing polycarbonate-based polyurethane resin.

[0050] The protective layer may be colored with the same dye or pigment as the colored skin layer, but from the viewpoint of light transmittance, it is preferable that the protective layer is not colored.

[0051] The protective layer resin composition liquid used for forming the protective layer can contain optional components as necessary within the range that does not impair the physical properties of the polyurethane resin. The optional components include, for example, crosslinking agents, silicone resins, viscosity adjusters, defoamers, antifouling agents, deodorants, antibacterial agents, and ultraviolet absorbing agents. These can be used alone or in combination of two or more.

[0052] The thickness of the protective layer is not particularly limited, and is, for example, preferably 2.5 to 15 μm, and more preferably 5 to 7.5 μm. By making the thickness equal to or greater than the lower limit, it is possible to improve abrasion resistance. By making the thickness equal to or less than the upper limit, it is possible to improve light transmittance. A soft feel can be obtained.

[0053] Next, a method for producing the leather-like sheet according to the present embodiment will be described. The method is not particularly limited. When the leather-like sheet is composed of only a colored skin layer, a conventionally known method such as an extrusion method or a coating method can be adopted. For example, the leather-like sheet according to the present embodiment can be produced by carrying out the following steps in order. That is, the method for producing the leather-like sheet according to the present embodiment is as follows: (1) A step of applying a resin composition liquid for a colored surface layer onto a releasable substrate to form a colored surface layer; (2) peeling off the release substrate; It includes.

[0054] In the above step (1), the resin composition liquid for colored skin layer is applied onto a releasable substrate. The method for applying the resin composition liquid for colored skin layer onto a releasable substrate can be any of various conventionally known methods, and is not particularly limited. For example, a method using a knife coater, a comma coater, a roll coater, a die coater, or the like can be mentioned. Among them, application by a knife coater or a comma coater is preferred because it is possible to form a uniform thin film layer.

[0055] The releasable substrate is not particularly limited, and may be a substrate having releasability against polyurethane resin, or a substrate that has been subjected to a release treatment. For example, release paper, release-treated cloth, water-repellent cloth, olefin sheet or film made of polyethylene resin or polypropylene resin, fluororesin sheet or film, plastic film with release paper, etc. may be mentioned. It is preferable that the releasable substrate has an uneven pattern.

[0056] The uneven pattern of the releasable substrate may have an arithmetic mean curvature (Spc) of the peaks of 140 or more, or 150 or more, and a developed area ratio (Sdr) of the interface of 0.3 or more, or 0.4 or more.

[0057] After the resin composition liquid for forming the colored surface layer is applied to the releasable substrate, a heat treatment is carried out as necessary to promote gelation.

[0058] In the above step (2), the releasable substrate is peeled off from the colored skin layer, thereby obtaining a leather-like sheet consisting of only the colored skin layer.

[0059] When the leather-like sheet is composed of a resin layer and a fibrous substrate in addition to the colored surface layer, a manufacturing method similar to that of conventionally known synthetic leathers can be adopted. Specifically, a calendaring method and a casting method can be mentioned. For example, the leather-like sheet of the embodiment can be manufactured by carrying out the following steps in order. That is, the manufacturing method is as follows: (A) applying a resin composition liquid for forming a colored surface layer onto a releasable substrate to form a colored surface layer; (B) bonding the colored skin layer and the fibrous base material; and (C) peeling off the release substrate; It includes.

[0060] The above step (A) is the step (1) described in the method for producing a leather-like sheet consisting of only a colored skin layer, in which a resin composition liquid for a colored skin layer is applied onto a releasable substrate as described above, and a heat treatment is performed if necessary.

[0061] In the above step (B), the colored skin layer and the fibrous substrate are laminated. Examples of the lamination method include a conventionally known method such as a transfer method, heat fusion, heat compression, and adhesion using an adhesive. The colored skin layer may be provided via an adhesive layer, or may be laminated directly on the fibrous substrate. The method of applying the resin composition liquid for the adhesive layer may be the same as the method of applying the resin composition liquid for the colored skin layer.

[0062] In the above step (C), the releasable substrate is peeled off from the colored skin layer, thereby obtaining a laminate of the colored skin layer and the fibrous substrate.

[0063] In the case of forming a heat insulating layer, in the above step (A), after forming a colored skin layer on a releasable substrate, the resin composition liquid for the heat insulating layer is applied on the colored skin layer before applying the resin composition liquid for the adhesive layer to form a heat insulating layer on the colored skin layer. In the case of forming a heat insulating layer and an anchor coat layer, after forming a heat insulating layer on the colored skin layer as described above, the resin composition liquid for the anchor coat layer is further applied on the heat insulating layer to form an anchor coat layer. Then, the resin composition liquid for the adhesive layer may be applied and then bonded to the fibrous substrate, or the anchor coat layer and the fibrous substrate may be bonded to each other without applying the resin composition liquid for the adhesive layer.

[0064] In addition, when a protective layer is formed, it may be formed by coating a resin composition liquid for the protective layer on the surface of the colored skin material of the laminate after peeling off the releasable substrate.

[0065] The method of applying the resin composition liquid for the heat insulating layer, the resin composition liquid for the anchor coat layer, and the resin composition liquid for the protective layer, and the heat treatment after application can be the same as that for forming the colored skin layer. In addition, when laminating a protective layer, the application method can also be a method of applying using a device such as a spray coater, a gravure coater, a gravure direct printing machine, a gravure offset printing machine, or a screen printing machine.

[0066] If necessary, an uneven pattern such as a grain pattern is formed on the colored skin layer (or the protective layer if a protective layer is formed). As a method for forming an uneven pattern after peeling off the release substrate, various conventionally known methods can be adopted, and the method is not particularly limited. For example, a method using laser processing can be mentioned.

[0067] Thus, the leather-like sheet according to one embodiment is obtained, although the method for producing the leather-like sheet according to this embodiment is not limited to the above method.

[0068] The use of the leather-like sheet according to the present embodiment is not particularly limited. Specific examples of the use include interior materials for various vehicles, such as automobile interior materials such as seats, ceiling materials, dashboards, door linings, and steering wheels, interior materials such as chairs and furniture, and fashion materials such as shoes, bags, and clothing.

[0069] In addition, the various numerical ranges described in the specification can be arbitrarily combined with their upper and lower limits, and all such combinations are considered to be preferred numerical ranges described in the specification. In addition, a numerical range described as "X to Y" means from X to Y. EXAMPLES

[0070] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0071] Each evaluation item was performed according to the following methods.

[0072] [Arithmetic mean curvature of the apex of the outermost surface (Spc) and developed area ratio of the interface at the outermost surface (Sdr)] A test piece was taken with a width of 100 mm and a length of 100 mm. The surface of the test piece was photographed using a laser microscope (VK-X3000, Keyence Corporation) (measurement magnification: 5 times). The photographed image was subjected to surface shape correction (correction strength: 5) to remove waviness in order to analyze the horizontal state using an analysis app (VK-X3000, multi-file analysis application, Keyence Corporation), and then smoothed (size: 5 x 5, type: median) to remove noise. The obtained image was used to measure the surface roughness of the analysis app, with the entire measurement area specified, and the Spc and Sdr values ​​were measured. The Spc and Sdr of the release paper were measured in the same manner as for the leather-like sheet, except that the smoothing conditions were changed to (size: 7×7, type: simple average).

[0073] [Dark Color Effect] The leather-like sheets were visually observed from the outermost surface (protective layer or colored skin layer) side and subjected to a sensory evaluation according to the following evaluation criteria. Note that, for leather-like sheets not containing a fibrous substrate, the leather-like sheet was placed on the fibrous substrate used in Example 1 and observed. (Evaluation Criteria) ○: The surface is slightly uneven, and the color is deep and has a deep color effect. ×: Micro-irregularities are not formed on the surface, the color does not have depth, and there is no deep color effect.

[0074] [Light transmittance of leather-like sheet] A test piece measuring 100 mm in width and 100 mm in length was taken. A floodlight (LED light rechargeable portable floodlight, manufactured by MEIKEE, light source: LED, light color: neutral white, light quantity: 100%) was placed in a dark place (a room without sunlight or artificial light sources). Using a luminance meter (LS-150, manufactured by Konica Minolta, Inc.), the luminance (luminance before transmission) was measured at a point 1 m away from the floodlight. Next, the test piece was placed over the floodlight so that the back side of the test piece was in close contact with the floodlight, and the luminance (luminance after transmission) was measured under the same conditions as above. The light transmittance was calculated from the following formula. Light transmittance (%) = Luminance after transmission (cd / m 2 ) ÷ Luminance before transmission (cd / m 2 ) x 100

[0075] [Light transmission and opacity] Based on the above [Light transmittance of leather-like sheet], the light transmittance of the leather-like sheet was measured and evaluated according to the following evaluation criteria. (Evaluation Criteria) ○: Light transmittance and opacity (light transmittance is 0.25-15%) ×: No light transmittance and / or hiding power (light transmittance is less than 0.25% or more than 15%)

[0076] [Concealment (sensory evaluation)] The leather-like sheet was visually observed from the outermost surface (protective layer or colored skin layer) side and subjected to a sensory evaluation according to the following evaluation criteria. Note that leather-like sheets without a fibrous substrate were observed by placing the leather-like sheet on the fibrous substrate used in Example 1. A score of △ or higher was considered to be acceptable. (Evaluation Criteria) ○: The fibrous base material is not visible (the fibrous base material is not visible) △: The fibrous base material is slightly transparent (the fibrous base material is slightly visible) ×: The fibrous base material is clearly visible (the fibrous base material is clearly visible)

[0077] [L * Value, a * Value, b * value] Using a spectrophotometer (e.g., Color I 5DV, manufactured by X-Rite, light source: C light source), the leather-like sheet was color-measured at any four points, and the average value was calculated. This average value was used as the L value of the leather-like sheet. * Value, a * Value, b * The average values ​​were rounded off to two decimal places and expressed to two decimal places.

[0078] [Example 1] <Fiber base material> A two-reed tricot knitting machine (HKS3M: manufactured by Nippon Meyer Co., Ltd.) was used as the fibrous base material. A full set of 56 dtex / 24 f polyester multifilament yarn was introduced as the front yarn to the front reed to form a denbi knit structure (1-2 / 1-0), and a full set of 56 dtex / 72 f polyester multifilament yarn was introduced as the back yarn to the back reed to form a cord knit structure (1-0 / 3-4). The tricot knit fabric (polyester fiber, basis weight 171 g / m 2 , thickness 0.6 mm, density 70 courses / 25.4 mm, 40 wells / 25.4 mm, uncolored) was knitted.

[0079] <Formulation 1-1: Resin composition liquid for colored surface layer> Base: Non-yellowing polycarbonate polyurethane resin: 100 parts by weight (Dainichiseika Color & Chemicals Mfg. Co., Ltd., Rezamin NE-8850, solid content 30% by mass) Pigment: Carbon black pigment: 1.67 parts by weight (DIC Corporation, DILAC BLACK L-8283S, inorganic pigment, solid content 25% by mass (pigment 15% by mass, dispersant 10% by mass) ·DMF: 50 parts by mass Preparation method: The viscosity was adjusted with DMF to 3,000 mPa·s (BII type viscometer (BHII type), manufactured by Toki Sangyo Co., Ltd., rotor: No. 4, 12 rpm, 23°C).

[0080] <Formulation 2: Resin composition liquid for adhesive layer> (1) Production Example 1: Polyisocyanate solution Polyol component: Polycarbonate polyol: 20 parts by weight (Ube Industries, Ltd., ETERNACOLL UH-200, solid content 100% by mass) Diisocyanate component: XDI type: 9.02 parts by weight (Mitsui Chemicals, Takenate 500, solid content 100% by mass) Preparation method: The above ingredients were mixed and heated from 25 to 80° C. at a rate of 1° C. / min. The mixture was stirred at 80° C. for 60 minutes to complete the urethane reaction, yielding a polyisocyanate solution. (2) Preparation Example 2: Polyol solution Base: Polycarbonate polyol: 30 parts by weight (Ube Industries, Ltd., ETERNACOLL UH-100, solid content 100 parts by mass) Catalyst: Amine catalyst: 2 parts by weight (TEDA-L33, Tosoh Corporation, solid content 100% by mass) Flame retardant: Phosphorus-based flame retardant: 20 parts by weight (Clariant Japan Co., Ltd., Pekoflam STC powder, solid content 100% by mass) ·DMF: 90 parts by mass Preparation method: The viscosity was adjusted with DMF to 10,000 mPa·s (BII type viscometer (BHII type), rotor: No. 4, 12 rpm, 23°C). (3) 29.02 parts by mass of the polyisocyanate solution of Production Example 1 and 152 parts by mass of the polyol solution of Production Example 2 were weighed out and mixed by stirring to obtain a resin composition liquid for adhesive layer. The viscosity of the resin composition liquid for adhesive layer was 10,000 mPa s (BII type viscometer (BHII type), manufactured by Toki Sangyo Co., Ltd., rotor: No. 4, 12 rpm, 23°C).

[0081] <Formulation 3: Resin composition liquid for protective layer> Base: Water-based polycarbonate polyurethane resin: 90 parts by weight (Manufactured by DIC Corporation, Hydran WLS-250, solid content 35% by mass) Matting agent: Silica-containing water-based polycarbonate polyurethane resin: 10 parts by weight (Dow Chemical Japan, HYDRHOLAC UD-2, solid content 26.5% by mass) Crosslinking agent: Isocyanate-based crosslinking agent (HDI-based): 1 part by weight (LANXESS, AQUADERM XL 50, solid content 50% by mass) Leveling agent: Silicone leveling agent: 1 part by weight (AAQUADERM Fluid H, manufactured by LANXESS AG, solid content 100% by mass) ·Water: 20 parts by mass Preparation method: The above-mentioned chemicals were mixed and stirred to prepare a resin composition for a protective layer. The viscosity of the obtained resin composition for a protective layer was 200 mPa·s (BII type viscometer (BHII type), manufactured by Toki Sangyo Co., Ltd., rotor: No. 1, 12 rpm, 23°C).

[0082] <Preparation of leather-like sheet> The resin composition liquid for colored surface layer prepared according to the above-mentioned Formulation 1-1 was applied to the release paper A having unevenness (Spc of release paper: 230, Sdr: 0.49) with an applicator in a dry coating amount of 35 g / m 2 The mixture was then heat-treated in a dryer at 80° C. for 2 minutes to form a colored skin layer.

[0083] Next, the adhesive layer resin composition liquid prepared according to the above-mentioned Formulation 2 was applied to the surface of the colored skin layer formed on the release paper with an applicator in a dry coating amount of 200 g / m 2 The adhesive was applied to a sheet so that the adhesive layer became thicker than the adhesive layer, and then heat-treated in a dryer at 100° C. for 1 minute to form an adhesive layer.

[0084] Then, the above-mentioned fibrous substrate was placed on the adhesive layer, and pressed with a press at 100°C and 394.2 kPa for 1 minute to bond the fibrous substrate to the adhesive layer. The release paper was then peeled off to obtain a laminate consisting of the colored skin layer, the adhesive layer, and the fibrous substrate.

[0085] Next, the protective layer resin composition liquid prepared according to the above-mentioned Formulation 3 was applied to the surface of the colored skin layer after peeling off the release paper with a reverse coater in a dry coating amount of 7.5 g / m 2 This was then heat-treated in a dryer at 80°C for 2 minutes to form a protective layer, thereby obtaining the leather-like sheet of Example 1. The protective layer had a thickness of 5 µm, the colored skin layer had a thickness of 35 µm, and the adhesive layer had a thickness of 200 µm.

[0086] The thickness of each resin layer was obtained by observing a vertical cross section of the leather-like sheet with a microscope (Keyence Corporation, Digital HF Microscope VH-8000), measuring the thickness at any 10 points, and calculating the average value of these values.

[0087] [Examples 2 to 5, Comparative Examples 1 to 4] A leather-like sheet was obtained in the same manner as in Example 1, except that the formulation of the resin composition for the colored surface layer and the release paper were changed as shown in Tables 1, 2, and 5.

[0088] Details of each pigment in Tables 2 to 4 are as follows. Inorganic pigment 2 (DIC Corporation, DILAC WHITE L-1781, inorganic pigment, solid content 43% by mass (pigment 40% by mass, dispersant 3% by mass) ·Inorganic pigment 3 (manufactured by DIC Corporation, DILAC BROWN L-1777S, inorganic pigment, solid content 37.5% by mass (30% by mass of pigment, 7.5% by mass of dispersant)) Organic pigment 1 (DIC Corporation, DILAC LEMON L-6644SK, organic pigment, solid content 25% by mass (pigment 15% by mass, dispersant 10% by mass) Organic pigment 2 (DIC Corporation, DILAC YELLOW L-6677S, organic pigment, solid content 22.5% by mass (pigment 15% by mass, dispersant 7.5% by mass) Organic pigment 3 (DIC Corporation, DILAC RED L-1759S-1, organic pigment, solid content 17.5% by mass (pigment 7.5% by mass, dispersant 10% by mass) ·Organic pigment 4 (manufactured by DIC Corporation, DILAC BLUE L-5858S, organic pigment, solid content 20% by mass (10% by mass of pigment, 10% by mass of dispersant))

[0089] [Example 6] A leather-like sheet was obtained in the same manner as in Example 1, except that no protective layer was formed.

[0090] [Example 7] In Example 1, after the colored skin layer was formed, a resin composition liquid for a heat insulating layer prepared according to the following formulation 4 was applied to the surface of the colored skin layer formed on the release paper in a dry coating amount of 90 g / m using an applicator. 2 The resin composition for the anchor coat layer was then applied to the surface of the heat insulating layer in a dryer at 100° C. for 3 minutes to form a heat insulating layer having a thickness of 120 μm. Next, the resin composition for the anchor coat layer prepared according to the following formulation 5 was applied to the surface of the heat insulating layer in a dry coating amount of 65 g / m using an applicator. 2 The mixture was dried in a dryer at 100° C. for 3 minutes and then at 130° C. for 3 minutes to form an anchor coat layer with a thickness of 22 μm. The rest of the procedure was the same as in Example 1 to obtain a leather-like sheet.

[0091] <Formulation 4: Resin composition for heat insulating layer> Base: Polycarbonate-based polyurethane resin with low yellowing resistance: 100 parts by weight (Manufactured by DIC Corporation, Hydran WLS-250, solid content 35% by mass) Hollow particles: pre-foamed microcapsules: 25 parts by weight (Matsumoto Microsphere FN-100S (made in a foamed state by heat treatment) manufactured by Matsumoto Yushi Seiyaku Co., Ltd., average particle size 50 μm, solid content 100% by mass, powder, outer shell: acrylonitrile polymer, inclusions: isopentane, foamed product) Crosslinking agent: Isocyanate-based crosslinking agent (HDI-based): 1 part by weight (LANXESS, AQUADERM XL 50, solid content 50% by mass) Leveling agent: Silicone leveling agent: 1 part by weight (LANXESS AG, AQUADERM Fluid H, solid content 100% by mass) Preparation method: The above-mentioned chemicals were mixed and stirred to prepare a resin composition for a foam layer. The viscosity of the obtained resin composition for a foam layer was 5,000 mPa·s (BII type viscometer (BHII type), manufactured by Toki Sangyo Co., Ltd., rotor: No. 4, 12 rpm, 23°C).

[0092] <Formulation 5: Resin composition for anchor coat layer> Base: Polycarbonate-based polyurethane resin with low yellowing resistance: 100 parts by weight (Manufactured by DIC Corporation, Hydran WLS-250, solid content 35% by mass) Crosslinking agent: Isocyanate-based crosslinking agent (HDI-based): 1 part by weight (LANXESS, AQUADERM XL 50, solid content 50% by mass) Leveling agent: Silicone leveling agent: 1 part by weight (LANXESS AG, AQUADERM Fluid H, solid content 100% by mass) Preparation method: The above-mentioned chemicals were mixed and stirred to prepare a resin composition for an anchor coat layer. The viscosity of the obtained resin composition for an anchor coat layer was 5,000 mPa·s (BII type viscometer (BHII type), manufactured by Toki Sangyo Co., Ltd., rotor: No. 4, 12 rpm, 23°C).

[0093] [Examples 8 to 13, Comparative Example 5] Leather-like sheets were obtained in the same manner as in Example 1, except that the formulations of the resin compositions for the resin layers and the release papers were changed as shown in Tables 1, 3, and 6.

[0094] [Examples 14 to 18] A leather-like sheet was obtained in the same manner as in Example 1, except that Formulation 1-11 of the resin composition for colored surface layer was applied to a sheet in a dry coating amount shown in Table 6.

[0095] [Examples 19 to 26, Comparative Examples 6 to 9] Leather-like sheets were obtained in the same manner as in Example 1, except that the formulation of each resin composition for the resin layer and the release paper were changed as shown in Tables 1, 2, 4, and 7.

[0096] [Example 27] As the fibrous base material, a 167 dtex / 48 f polyester multifilament yarn was used as the warp yarn, and a 167 dtex / 48 f polyester multifilament yarn was used as the weft yarn, to produce a woven fabric (polyester fiber, basis weight 230 g / m) with the structure shown in FIG. 2 A leather-like sheet was obtained in the same manner as in Example 1, except that a polyester fiberboard having a thickness of 0.6 mm, warp density of 130 threads / 25.4 mm, weft density of 75 threads / 25.4 mm, and uncolored was prepared.

[0097] [Example 28] A leather-like sheet of Example 28 was obtained, which was composed only of the colored resin layer of Example 1. That is, the resin composition liquid for colored surface layer prepared according to the above-mentioned formulation 1-1 was applied to release paper A having unevenness (Spc of release paper: 230, Sdr: 0.49) with an applicator in a dry coating amount of 35 g / m 2 The mixture was then heat-treated in a dryer at 80° C. for 2 minutes to form a colored skin layer, thereby obtaining a leather-like sheet.

[0098] [Comparative Example 10] The procedure was exactly the same as in Example 28, except that release paper D was used instead of release paper A, to obtain a leather-like sheet of Comparative Example 10 consisting only of a colored resin layer.

[0099] [Table 1]

[0100] [Table 2]

[0101] [Table 3]

[0102] [Table 4]

[0103] [Table 5]

[0104] [Table 6]

[0105] [Table 7]

[0106] [Table 8]

[0107] The evaluation results for Examples 1 to 28 and Comparative Examples 1 to 10 are shown in Tables 5 to 8. In Comparative Examples 1, 2, 5, and 10, the leather-like sheet had an Spc of less than 100 and an Sdr of less than 0.15, so that the light transmittance and concealment were excellent, but the dark color effect was poor. In Comparative Example 3, the leather-like sheet had an Spc of less than 100 and an Sdr of less than 0.15, and the light transmittance was 0.1%, so that the concealment was excellent, but the light transmittance and dark color effect were poor. In Comparative Example 4, the light transmittance was 0.1%, so that the concealment and dark color effect were excellent, but the light transmittance was poor. In Comparative Examples 6 to 8, the leather-like sheet had an Spc of less than 100 and an Sdr of less than 0.15, and the light transmittance was 8.3% to 13.5%, so that the light transmittance was excellent, but the concealment and dark color effect were poor. In Comparative Example 9, the light transmittance was 19.9%, so the light transmittance and deep color effect were excellent, but the hiding power was poor. In contrast, Examples 1 to 28 were excellent in light transmittance and design (deep color effect, hiding power). Examples 1 to 5 were excellent in abrasion resistance compared to Example 6 (without protective layer). Example 7 was excellent in durability such as abrasion resistance and heat insulation compared to Examples 1 to 5 (without anchor coat layer and heat insulation layer). [Explanation of symbols]

[0108] 1,10,100 Leather-like sheet 11 Colored epidermal layer 12 Fibrous base material 13 Adhesive layer 14 Protective layer 15 Anchor coat layer 16 Thermal insulation layer 2. Texture

Claims

1. The leather-like sheet is made of at least one colored skin layer and has an uneven pattern on its outermost surface, the arithmetic mean curvature (Spc) of the peaks of the outermost surface is 100 or more, the developed area ratio (Sdr) of the interface at the outermost surface is 0.15 or more, and the light transmittance of the leather-like sheet is 0.25 to 15%.

2. L ＊ a ＊ b ＊ The L of the leather-like sheet in the color system ＊ Value is 30 or less, a ＊ Value and b ＊ 2. The leather-like sheet according to claim 1, wherein the values ​​of the color and the reflectance are both -1.0 or more and 1.0 or less, the colored surface layer contains 0.5 to 1.3 mass % of an inorganic pigment, and the light transmittance of the leather-like sheet is 0.25 to 2.5%.

3. L ＊ a ＊ b ＊ The L of the leather-like sheet in the color system ＊ Value is 30 or less, a ＊ Value and b ＊ 2. The leather-like sheet according to claim 1, wherein the values ​​of the color and the reflectance are both -1.0 or more and 1.0 or less, the colored surface layer contains 5 to 7.5% by mass of only organic pigments, and the light transmittance of the leather-like sheet is 0.25 to 5%.

4. L ＊ a ＊ b ＊ The L of the leather-like sheet in the color system ＊ 2. The leather-like sheet according to claim 1, wherein the value is 35 or more, the colored surface layer contains 5 to 15% by mass of inorganic pigment and / or organic pigment, and the light transmittance of the leather-like sheet is 2.5 to 15%.

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