JP2022136432A - Leather-like sheet and decorative molded article - Google Patents

Abstract

To provide a leather-like sheet considered about a fear of slipping an article off from a surface, and excellent in a grip property to an article.SOLUTION: A leather-like sheet is obtained by coating one face of a fiber substrate with a resin layer composed of a polymer elastomer as a main constituent where the maximum value T1 of 20% tension at 20°C is 4 kg/2.5 cm or greater, the surface of a resin layer has an embossed uneven face, and an area of a region corresponding to a part of 80% or more of a maximum height Sz in surface roughness measurement according to ISO 25178 is 25-65% of a total area.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a leather-like sheet having excellent grip on an article.

BACKGROUND ART Leather-like sheets are used as exterior materials for bags, clothes, interior materials for vehicles, aircraft, etc., exterior materials for housings of mobile phones, mobile devices, home electric appliances, building materials, furniture miscellaneous goods, sporting goods, and the like. Also known is a decorative molded article in which such a leather-like sheet is arranged on the surface of a resin molded article.

For example, Patent Document 1 below includes a fiber fabric, a grain layer containing a polymeric elastomer laminated on the fiber fabric, and a skin layer covering the grain layer, and the skin layer has a 100% modulus of 1 MPa. Disclosed is an artificial leather that is a film having an average thickness of 0.1 to 5 μm containing a polyurethane component containing 30 to 80% by mass of the following polyurethane and hollow nanosilica particles having an average primary particle diameter of 200 to 300 nm. It is also disclosed that such artificial leather has dimples on the surface on which the grain layer and skin layer are formed. It is also described that such an artificial leather has not only excellent wet grip but also remarkably excellent dry grip, and is preferably used as a surface material for balls.

In addition, although it is not a leather-like sheet, in the following Patent Document 2, a base sheet made of nonwoven fabric or the like is preliminarily impregnated or coated with a resin water repellent compound containing a spreading agent such as an acrylic ester resin. or a spraying method, and a resin emulsion composition such as acrylic resin, polyurethane resin, ethylene vinyl acetate resin, etc. is distributed on at least one side of the base sheet at intervals, and Disclosed is an anti-slip sheet material in which projecting resin bodies having relatively uniform projection heights are scattered.

Japanese Unexamined Patent Application Publication No. 2015-101802 JP-A-7-178855

If the surface of the leather-like sheet does not have sufficient grip on an article, there is a concern that the object may slide down when placed on the surface of the leather-like sheet. In such a case, for example, when a leather-like sheet is used as an interior material for a vehicle or an aircraft, and an article such as a portable terminal device is placed on the surface of the leather-like sheet, the vehicle or airplane may not take off. It is envisaged that the article will sometimes slide off the surface of the leather-like sheet.

SUMMARY OF THE INVENTION An object of the present invention is to provide a leather-like sheet having excellent grip on an article, taking into consideration the concern that the article may slip off the surface of the leather-like sheet.

The inventors of the present invention have diligently studied the factors that make an article easy to slide down when the article is placed on the surface of a resin layer having an embossed uneven surface such as grains that form a leather-like sheet. I found This factor will be explained with reference to FIG. In FIG. 4, 20 is a conventional leather-like sheet having an embossed uneven surface on one surface of a fiber base material 11 and coated with a resin layer 12 mainly composed of an elastic polymer. M is a resin layer. It is an article placed on 12 embossed uneven surfaces. As shown in FIG. 4(a), when an article M is placed on the embossed uneven surface of the resin layer 12 of the leather-like sheet 20, the article M is in close contact with the convex portions of the embossed uneven surface. In such a case, as shown in FIG. 4(b), when a force is applied to the article M in the horizontal direction indicated by the arrow, the frictional force between the article M and the protrusions of the embossed uneven surface causes the leather to crack. It has been found that when the sheet 20 is bent, a convex portion that does not come into contact with the article M is generated and a void v is formed. As a result of the formation of protrusions that do not come into contact with the article M, the inventors have found that the article M is in contact with the protrusions, resulting in a decrease in grip performance. In particular, the inventors have noticed that such bending of the leather-like sheet 20 is more likely to occur as the fiber base material 11 is more supple and softer. The inventors of the present invention have made intensive studies based on such knowledge, and have arrived at the present invention.

That is, one aspect of the present invention is a leather-like sheet in which a resin layer mainly composed of an elastic polymer is coated on one surface of a fiber base material, and the maximum value T1 of 20% strength at 20° C. is 4 kg/2. .5 cm or more, the surface of the resin layer has an embossed uneven surface, and the area of the region corresponding to 80% or more of the maximum height Sz in the surface roughness measurement according to ISO 25178 is 25 to 25 cm of the total area. It is a leather-like sheet that is 65%. According to such a leather-like sheet, since the area of the region corresponding to the convex portion of the embossed uneven surface is appropriate, the static frictional resistance of the embossed uneven surface to the article is increased, and the grip on the article is improved. Further, since the maximum value T1 of 20% strength at 20°C of the leather-like sheet is 4 kg/2.5 cm or more, when an article placed on the embossed uneven surface receives force in the horizontal direction and starts to move, the leather-like sheet becomes Since the sheet is less likely to bend, the contact surface between the article and the protrusions of the embossed uneven surface is less likely to become smaller. As a result, a leather-like sheet having excellent grip on an article can be obtained.

Polyurethane, for example, is preferably used as the elastic polymer.

Moreover, it is preferable that the surface of the resin layer has a coefficient of static friction of 0.55 or more from the viewpoint of maintaining sufficient grip on general articles such as smartphones.

Further, it is preferable that the maximum height Sz of the embossed uneven surface is 30 to 100 μm from the viewpoint of maintaining sufficient grip on general articles while maintaining the design of the surface.

In addition, it is preferable that the maximum value T2 of the 20% strength at 20° C. of the fiber base material is 2.5 kg/2.5 cm or more from the viewpoint of easily forming a leather-like sheet that is hard to bend.

Further, the ratio T2/T1 of the maximum 20% strength T2 of the fiber base to the maximum 20% strength T1 of the leather-like sheet is 0.5 to 2.0. It is preferable from the viewpoint that the above-described leather-like sheet can be easily obtained.

Another aspect of the present invention is a decorative molded article comprising a resin molded article and a decorative layer attached to the surface of the resin molded article, wherein the decorative layer is any of the above leathers. It is a decorative molding that is a like sheet. According to such a decorative molded article, when an article is placed on the surface of the article, the fiber base material does not easily sink into the article.

According to the present invention, a leather-like sheet having excellent grip on an article can be obtained.

FIG. 1 is a schematic cross-sectional view of a leather-like sheet 10 of an embodiment. FIG. 2 is a schematic cross-sectional view for explaining each step of forming a decorative molding using the leather-like sheet 10. As shown in FIG. FIG. 3 is a diagram showing the surface properties used to calculate the area of the region corresponding to 80% or more of the maximum height Sz of the embossed uneven surface 2a of the leather-like sheet obtained in Example 1. FIG. FIG. 4 is an explanatory diagram for explaining the factors that cause an article to easily slide down when placed on the embossed uneven surface of the conventional leather-like sheet 20 .

Hereinafter, the leather-like sheet of this embodiment will be described in detail with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of a leather-like sheet 10 of this embodiment. As shown in FIG. 1, the leather-like sheet 10 is a leather-like sheet made of artificial leather, synthetic leather, or the like, in which one surface of a fiber base material 1 is coated with a resin layer 2 mainly composed of an elastic polymer. The resin layer 2 has an embossed uneven surface 2a on its surface.

As will be described later, the leather-like sheet 10 has a maximum value T1 of 20% strength at 20°C of 4 kg/2.5 cm or more, and the embossed uneven surface 2a has a maximum It has an uneven surface in which the area corresponding to 80% or more of the height Sz is 25 to 65% of the total area.

The fiber base material includes a non-woven fabric, a woven fabric, a knitted fabric, or a fiber entangled body in which these are combined, and preferably includes an elastic polymer impregnated into the fiber entangled body. Among these, a fiber base material obtained by impregnating a nonwoven fabric of ultrafine fibers with a polymer elastic body as described later is excellent in a feeling of fullness, so the maximum value T1 of 20% strength at 20 ° C. is 4 kg / 2. It is particularly preferable from the point that a fiber base material having a length of 0.5 cm or more can be obtained.

The type of fibers forming the fiber entanglement is not particularly limited. Specific examples of resins forming fibers include polyethylene terephthalate (PET), modified polyethylene terephthalate, polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polytriethylene terephthalate, polyhexamethylene terephthalate, and polypropylene terephthalate. , aromatic polyester resins such as polyethylene naphthalate; aliphatic polyester resins such as polylactic acid, polyethylene succinate, polybutylene succinate, polybutylene succinate adipate, polyhydroxybutyrate-polyhydroxyvalerate copolymer; Nylon resins such as nylon 6, nylon 66, nylon 610, nylon 10, nylon 11, nylon 12, nylon 6-12; polypropylene, polyethylene, polybutene, polymethylpentene, chlorine-based polyolefin, ethylene-vinyl acetate copolymer, styrene Examples thereof include polyolefin resins such as ethylene copolymers.

In addition, the fineness of the fibers forming the fiber entangled body is not particularly limited. It is preferable from the viewpoint that it is easy to obtain a fiber base material having a supple texture with a feeling of fullness and having a maximum value T1 of 20% strength at 20° C. of 4 kg/2.5 cm or more. The ultrafine fibers may exist as fiber bundles formed by a plurality of ultrafine fibers bundled together, such as those formed through ultrafine fiber-forming fibers such as islands-in-the-sea composite fibers.

Moreover, it is preferable that the fiber base material contains an elastic polymer impregnated into the fiber entangled body. Specific examples of the elastic polymer impregnated into the fiber entangled body include, for example, polyurethane, acrylonitrile elastomer, olefin elastomer, polyester elastomer, polyamide elastomer, and acrylic elastomer. Among these, polyurethanes, and crosslinked waterborne polyurethanes obtained by coagulating waterborne polyurethane emulsions, particularly crosslinked waterborne polyurethanes containing polycarbonate/ether polyurethanes, have a maximum tenacity of 20% at 20°C. This is preferable because a leather-like sheet having a value T1 of 4 kg/2.5 cm or more can be easily obtained.

The content of the polymeric elastomer in the fiber base material is not particularly limited, but is preferably 5 to 60% by mass, more preferably 8 to 40% by mass. The thickness of the fiber base material is not particularly limited, but is preferably 250 to 750 μm, more preferably 300 to 500 μm.

As the fiber base material, a highly rigid fiber base material, specifically, for example, the maximum value T2 of 20% strength at 20 ° C. is 2.5 kg / 2.5 cm or more, further 2.5 to 15 kg / 2 It is preferably a stiff fibrous substrate, such as 0.5 cm. By using such a hard fiber base material, a leather-like sheet that is difficult to bend can be easily formed. As a result, it becomes easier to obtain a leather-like sheet that retains high grip properties. If the maximum value T2 of the 20% strength at 20° C. of the fiber base material is too low, as described above, when the article placed on the surface of the resin layer starts to move, the fiber base material bends and the resin layer is bent. The surface tends to sink, and as a result, the adhesion between the article and the protrusions of the resin layer tends to decrease.

Here, the maximum value of 20% strength at 20°C is the 20% strength at 20°C of the leather-like sheet or fiber substrate measured as described later. Usually, the maximum strength is 20% in the MD direction (longitudinal direction) parallel to the running direction of the leather-like sheet or fiber substrate production line. That is, the leather-like sheet or fiber base material is produced while tension is applied in the advancing direction of the production line and the fibers are stretched the most in the MD direction. be a value.

The 20% strength at 20 ° C. of the fiber base material is the fineness, type and strength of the fibers forming the fiber base material, the entanglement structure of the fiber entanglement, the degree of entanglement adjusted by needle punching, etc., apparent density, basis weight, It is adjusted by adjusting the thickness or the like. That is, when the strength of the fiber is high, when the degree of entanglement is high, when the apparent density is high, when the fiber is thick, and when the basis weight is high, the tenacity increases by 20%.

Although the apparent density of the fiber base material is not particularly limited, it is preferably 0.20 to 1.00 g/cm ³ , particularly 0.30 to 1.00 g/cm ³ .

A leather-like sheet can be obtained by forming a resin layer mainly composed of an elastic polymer on one surface of such a fiber base material.

Examples of the elastic polymer that forms the main component of the resin layer include polyether-polyester polyurethane, polycarbonate polyurethane, silicone-modified polycarbonate polyurethane, and polyether-polyester polyurethane, polycarbonate polyurethane, silicone-modified polycarbonate polyurethane, Polyurethanes such as polyether-based polyurethanes and polyester-based polyurethanes; acrylic elastic bodies; polyurethane-acrylic composite elastic bodies; silicone-based elastic bodies; polyvinyl chloride-based elastic bodies; Among these, polyurethane is preferable because it has an excellent balance between abrasion resistance and scratch resistance of the surface and grip properties.

The resin layer is mainly composed of an elastic polymer, and if necessary, colorants such as pigments and dyes, softening agents, antifouling agents, hydrophilizing agents, lubricants, anti-deterioration agents, ultraviolet absorbers, flame retardants, etc. may contain additives. The term "mainly composed of an elastic polymer" means that the resin layer contains the elastic polymer in an amount of 50% by mass or more, preferably 80% by mass or more, and more preferably 90% by mass or more.

The 100% modulus of such a resin layer is 2 to 100 MPa, further 25 to 50 MPa at 20 ° C., which is excellent in balance between the difficulty of bending of the uneven surface and the flexible elasticity of the surface. preferred from

The storage elastic modulus of the resin layer is preferably 2 to 80 MPa, more preferably 25 to 50 MPa, from the standpoint of excellent balance between the resistance to bending of the uneven surface and the flexible elasticity of the surface.

The thickness of the resin layer is not particularly limited, but when it is 30 to 500 μm, further 50 to 200 μm, it is easy to form an embossed uneven surface, and the leather-like sheet has a flexible surface with cushioning properties. It is preferable from the point of being able to sufficiently impart a grain-finished design.

Such a resin layer may be composed of a homogeneous single layer, or may have a laminated structure in which multiple layers are laminated such as an adhesive layer, an intermediate layer, and a skin layer.

In the resin layer laminated on the leather-like sheet, the area of the region corresponding to 80% or more of the maximum height Sz in the surface roughness measurement according to ISO 25178 is 25 to 65% of the total area. It has an embossed uneven surface 2a with a surface.

Here, the surface roughness measurement according to ISO 25178 means that a special striped pattern is projected onto the surface of the article, the reflected light is received by a CMOS sensor, and the surface texture is mathematically determined from the received light. It is a measurement method for measuring the three-dimensional surface texture of an object surface by forming an image that expresses the surface texture by a calculation method, and is measured with a non-contact surface roughness/shape measuring instrument. Then, based on the measured three-dimensional surface properties of the object surface, the maximum height Sz, the arithmetic mean height Sa, the root mean square height Sq, the skewness Ssk, the kurtosis Sku, the maximum peak height Three-dimensional surface roughness parameters such as height Sp and maximum valley depth Sv can be calculated.

The maximum height Sz in surface roughness measurement according to ISO 25178 represents the distance from the highest point to the lowest point on the embossed uneven surface. The area of the region corresponding to 80% or more of the maximum height Sz is generated by generating a height contour map from the image showing the three-dimensional surface texture including information on the height difference of the surface. can be calculated by performing a binarization process using a contour line corresponding to a portion of 80% or more of the maximum height Sz as a threshold.

The resin layer laminated on the leather-like sheet preferably has an embossed uneven surface in which the area of the region corresponding to 50% or more of the maximum height Sz is 60 to 90% of the total area. By having such an uneven surface, there is a tendency that the article can be brought into closer contact with the protrusions of the uneven surface and a high coefficient of static friction can be maintained.

The resin layer laminated on the leather-like sheet has an embossed uneven surface with an area corresponding to 80% or more of the maximum height Sz of 25 to 65%, preferably 25 to 60% of the total area. have a face. By having such an uneven surface, the article can be brought into close contact with the protrusions of the uneven surface, and a high coefficient of static friction can be maintained. If the area of the region corresponding to 80% or more of the maximum height Sz is less than 25% of the total area, the contact area between the uneven surface and the article will be small. Since the unevenness is small and the resistance accompanying the bending of the protrusions generated when the article starts to move becomes small, it becomes difficult to maintain a high coefficient of static friction.

In the surface roughness measurement according to ISO 25178, the leather-like sheet has parameters such as the arithmetic mean height Sa, the root mean square height Sq, the skewness Ssk, the kurtosis Sku, the maximum peak height Sp, and the maximum valley depth Sv. Although not particularly limited, for example, the following range is preferable. Sa is preferably 5 to 15 μm, Sq is 5 to 15 μm, Sku is 1 to 5, Ssk is −2 to −0.4, Sp is 10 to 25 μm, and Sv is preferably 15 to 60 μm. .

As a method for forming an embossed uneven surface on the surface of the resin layer of the leather-like sheet, for example, a textured uneven surface is transferred to the surface of the resin film, so that the maximum height Sz is 80%. A method using a release paper having an uneven surface designed to form a resin film having an uneven surface such that the area corresponding to the above portions is 25 to 65% of the total area. Specifically, a resin liquid for forming a resin film mainly composed of an elastic polymer is applied to the surface of such a release paper, and solidified to form a resin film having an embossed uneven surface. .

Then, as described above, an adhesive for forming an adhesive layer is applied to the surface of the resin film formed on the release paper having an uneven surface, the adhesive is applied to the surface of the fiber base material, and pressed if necessary. After bonding, peel off the release paper. Thus, a leather-like sheet as described above can be produced.

The release paper for forming the embossed uneven surface as described above is composed of, for example, paper as a substrate and a release layer for transferring the embossed uneven surface. The types of paper include semi-bleached paper, fine paper, glassine paper, etc., and a silicone resin is used for the release layer. The rugged surface of the release layer is adjusted by pressing a master mold with a different surface rugged shape onto a silicone resin and curing it in that shape. The release layer has appropriate adhesion to the resin layer of the leather-like sheet, and has the ability to be released after curing.

The release paper to be used is appropriately selected in consideration of the concavo-convex transferability of the resin layer to be used. A paper pattern is preferably used.

As described above, the leather-like sheet of the present embodiment is a leather-like sheet in which a resin layer mainly composed of an elastic polymer is coated on one surface of a fiber base material, and the maximum strength of 20% at 20 ° C. T1 is 4 kg / 2.5 cm or more, the surface of the resin layer has an embossed uneven surface, and the area of the region corresponding to 80% or more of the maximum height Sz in the surface roughness measurement according to ISO 25178 It is a leather-like sheet with 25-65% of the total area.

The leather-like sheet of the present embodiment has a maximum value T1 of 20% strength at 20° C. of 4 kg/2.5 cm or more, preferably 4 to 25 kg/2.5 cm, particularly preferably 4 to 15 kg/2.5 cm. Some relatively hard leather-like sheets. Such a hard leather-like sheet is less likely to bend when an article placed on its surface begins to move, and as a result retains a high degree of grip. When the maximum value T1 of the 20% strength of the leather-like sheet at 20° C. is less than 4 kg/2.5 cm, as described above, the leather-like sheet begins to move when the article placed on the surface of the resin layer starts to move. As a result, the surface of the resin layer tends to sink, and as a result, the adhesion between the article and the protrusions of the resin layer is reduced. Also, if the maximum value T1 of the 20% strength of the leather-like sheet at 20°C is too high, the leather-like sheet tends to lose its supple texture.

Further, in the leather-like sheet of the present embodiment, the ratio T2/T1 of the maximum 20% strength T2 of the fiber base to the maximum 20% strength T1 of the leather-like sheet is 0.5 to 2.0, and A ratio of 0.5 to 1.0 is preferable from the viewpoint that the above-described leather-like sheet can be easily obtained because the stiffness of the fiber base material is relatively high. If T2/T1 is too small, the leather-like sheet will flex, which tends to produce protrusions that do not come into contact with the article, leading to a decrease in grip performance. Since it is soft to the fiber base material, the embossed uneven surface of the resin layer is easily deformed when an article is placed on it, and the article cannot obtain sufficient static friction resistance from the uneven surface, resulting in a decrease in grip performance. tend to

The thickness of the leather-like sheet is 300 to 1500 μm, more preferably 400 to 1000 μm, because it facilitates the formation of a resin layer having an embossed uneven surface and the formation of a less flexible leather-like sheet. preferable.

Such a leather-like sheet of the present embodiment has a static friction coefficient of 0.55 or more, more preferably 0.6 or more, particularly 0.6 to 0.6 to 0.6, measured as described later on the surface of the resin layer. A value of 9 is preferable from the viewpoint of exhibiting a sufficient gripping property to prevent the article from slipping off the surface. In addition, the coefficient of dynamic friction of the surface of the resin layer measured as described later is 0.3 or more, further 0.4 or more, and particularly 0.4 to 0.9, so that it does not slip even when it starts to move. It is preferable from the point of exhibiting a sufficient grip for stopping.

The leather-like sheet described above can be used for any of the conventionally known leather-like sheet applications without particular limitation. , furniture, miscellaneous goods, sporting goods, etc., where articles are placed on the surface and are required to be difficult to slide off. Moreover, as such an application, it is particularly preferably used as a leather-like sheet formed with a decorative molded article for decorating the surface forming a housing.

The decorative molded article of the present embodiment is a decorative molded article in which a decorative layer is attached to the surface of a resin molded article, and the leather-like sheet described above is used as the decorative layer. Such decorative moldings can have a leather-like surface that provides a good grip on the article.

Such a decorative molding is produced by trimming a leather-like sheet to match the shape of the surface to which the resin molding is to be adhered, and adhering the trimmed leather-like sheet to the surface to be adhered with an adhesive. In-mold molding is used to integrate a leather-like sheet on the surface of a resin molding molded by injection molding at the same time as injection molding.

Referring to FIG. 2, a leather-like sheet 10 is used as a decorative layer and decorative molding is performed by in-mold molding by injection molding to obtain a decorative surface that is a leather-like surface having three-dimensional embossed uneven surfaces. A process of molding a decorative molded body having

As shown in FIG. 2A, the mold 17 includes a movable mold 17a having a cavity C and a fixed mold 17b. First, the leather-like sheet 10 having an embossed uneven surface is placed on the surface of the movable mold 17a forming the cavity C so that the resin layer 2 faces.

The leather-like sheet 10 is formed into a preform molded body that is formed in advance along the shape of the cavity C of the mold 17 used for in-mold molding by hot press molding, vacuum molding, vacuum pressure molding, or the like. is preferred.

Then, as shown in FIG. 2(b), a molten resin 30a is injected by injection molding onto the fiber base 1 side of the back surface of the leather-like sheet 10 in the mold 17 with respect to the surface on which the resin layer 2 is arranged. Thus, an in-mold molded body having the leather-like sheet 10 integrated on its surface is formed. Specifically, the movable side mold 17a and the fixed side mold 17b are clamped, the cylinder 18 of the injection molding machine 7 is advanced until the nozzle 16 contacts the sprue bush 17f of the fixed side mold 17b, and the injection molding machine is opened. By injecting the molten resin 30a melted in the cylinder 18 with the screw 19, the molten resin 30a is injected into the mold 17 for injection molding. The injected molten resin 30a flows through the resin channel R in the mold 17, flows into the cavity C, and is filled therein. At this time, when the leather-like sheet 10 is a leather-like sheet provided with the resin layer 2 laminated on the fiber base 1, the molten resin 30a appropriately permeates the fiber base 1, so injection molding is performed. The molded injection molded body 30 is integrated with the leather-like sheet 10 so as to maintain high adhesiveness due to the anchoring effect.

Resins injected by injection molding include ABS resins, polycarbonate resins, polyolefin resins such as polypropylene, polyester resins such as polyethylene terephthalate (PET) and polybutylene terephthalate (PBT), and various polyamide resins. Various thermoplastic resins can be used without particular limitation.

Injection molding conditions are the melting point and melt viscosity of the resin to be injected, the shape of the molded body, and the conditions that allow the resin to flow to the end of the flow (resin temperature, mold temperature, injection pressure, injection speed, injection later holding pressure, cooling time) are appropriately selected.

After the injection is finished, as shown in FIG. 2(c), the molten resin 30a is cooled to form an injection molded body 30, and an in-mold molded body 31 integrated with the leather-like sheet 10 is molded. Then, as shown in FIG. 2(d), by opening the mold 17, the movable side mold 17a and the fixed side mold 17b are separated, and the in-mold molded body 31 having the runner 32 is taken out. be Then, by removing the runner 32, a decorative molding 40 is obtained as shown in FIG. 2(e).

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples. In addition, the present invention is not limited at all by the examples.

First, the evaluation methods used in the examples will be collectively described below.

(Measurement of surface texture according to ISO 25178)
The surface properties of the surface of the resin layer of the leather-like sheet according to ISO 25178 were measured using a non-contact surface roughness/shape measuring instrument "Digital Macroscope VHX-6000" (manufactured by Keyence Corporation). . Specifically, a 18 mm × 24 mm area on the surface of the resin layer of the leather-like sheet was irradiated with structured illumination light from a high-intensity LED, and a 4-megapixel monochrome C-MOS camera produced distortion at a magnification of 100 times. A fringe projection image was taken. Then, the obtained image was analyzed and processed to obtain the maximum height Sz. Further, arithmetic mean height Sa, root mean square height Sq, skewness Ssk, kurtosis Sku, maximum peak height Sp, and maximum valley depth Sv were obtained. The measurement was performed 3 times and the average value was adopted as each numerical value. Further, for the area of the region corresponding to 80% or more of the maximum height Sz and the area of the region corresponding to 50% or more of the maximum height Sz, a height contour map is generated from the observation image, and the height contour map is obtained as an image. It was calculated by binarizing with processing software. FIG. 3 shows a height contour diagram of the surface of the resin layer of the leather-like sheet obtained in Example 1 and a binarized image thereof.

(20% stronger)
The leather-like sheet was left in a constant temperature and humidity environment of 20° C. and 65 RH% for 20 hours. Then, using a 2.5 cm × 16 cm test piece cut out from the leather-like sheet and a universal material testing machine (Instron 5566, manufactured by Instron, Inc., USA), JIS L 1096 8.12.1 "Tensile strength test" was performed. to obtain the stress-strain curve. Then, the stress at 20% elongation was read from the stress-strain curve to obtain the 20% strength. In the test, since the maximum value is obtained in the MD direction along the direction of progress of the manufacturing process of the leather-like sheet, 3 test pieces in the MD direction were measured and the average value thereof was taken as 20% strength. Tensile speed is 200mm/min. and

(thickness of leather-like sheet, resin layer and fiber base material)
The thicknesses of the leather-like sheet, the resin layer and the fiber base material were measured using a "dial thickness gauge" (Peacock, model: H, manufactured by Ozaki Seisakusho Co., Ltd.). The measurement was performed 5 times and the average value was obtained.

(100% modulus of resin layer)
A film having a thickness of about 400 μm was prepared from the polyurethane composition forming the resin layer used in each example and comparative example, and the film was cut into a width of 2.5 cm. was measured for strength and elongation. Tensile speed is 200mm/min. and The strength at 100% elongation of the obtained SS curve was read and divided by the cross-sectional area obtained from the film thickness and 2.5 cm width to obtain the 100% modulus (MPa).

(Storage modulus of resin layer)
A film having a thickness of about 120 μm was prepared from the polyurethane composition forming the resin layer used in each example and comparative example, and a test piece cut into 5×10 mm was used to measure dynamic viscoelasticity using a dynamic viscoelasticity measuring device (UBM). The storage modulus at room temperature (27° C.) was measured using Rheogel-E400 manufactured by Co., Ltd.). The measurement conditions were as follows: frequency 11 Hz, sample size: 5×10 mm, thickness: 0.12 mm, measurement temperature: 0 to 240° C., heating rate: 3° C./min. , measurement mode: tension, waveform: sine wave.

(Coefficient of friction)
A test piece of 100 mm×200 mm was cut out from the leather-like sheet. Then, a static friction coefficient (μS) and a dynamic friction coefficient (μD) were calculated with reference to JIS K 7125 using a friction wear tester (HEIDON tripogear TYPE: 18L manufactured by Shinto Kagaku Co., Ltd.). A square flat contact with a size of 30 mm×30 mm and made of aluminum was used as the contact. A load of 200 g was applied.

Moreover, the fiber base material used in the present Example is demonstrated below.
Fiber base material A: Fiber bundles (average 25 fibers/bundle) of PET ultrafine fibers having a single fiber fineness of 0.08 dtex obtained by removing the sea component from a nonwoven fabric of long fiber sea-island composite fibers are entangled. A fibrous base material having a thickness of 370 μm, which is formed by impregnating a nonwoven fabric having an apparent density of 0.45 g/cm ³ with a crosslinked polycarbonate/ether-based polyurethane. The mass ratio of polyurethane/nonwoven fabric of the fiber base material was 22/78.
Fiber base material B: Fiber bundles (average 25 fibers/bundle) of PET ultrafine fibers having a single fiber fineness of 0.08 dtex obtained by removing the sea component from a nonwoven fabric of long fiber sea-island composite fibers are entangled. A fibrous base material having a thickness of 470 μm, which is formed by impregnating a nonwoven fabric having an apparent density of 0.53 g/cm ³ with a crosslinked polycarbonate/ether-based polyurethane. The mass ratio of polyurethane/nonwoven fabric of the fiber base material was 22/78.
Fiber base material C: A fiber bundle (average 25 fibers/ A fibrous base material having a thickness of 450 μm, which is formed by impregnating a nonwoven fabric having an apparent density of 0.36 g/cm ³ in which bundles) are entangled with a crosslinked polycarbonate/ether-based polyurethane. The mass ratio of polyurethane/nonwoven fabric of the fiber base material was 39/61.
Fiber base material D: Fiber base material C is subjected to softening treatment by soaking in a solvent and kneading.

In addition, the textured release paper used in this example has a base material of fine paper and a release layer of silicone resin, has a leather-like appearance texture, and has a three-dimensional surface property of the release layer surface, which is the maximum height Sz (μm) and arithmetic mean height Sa (μm) are release papers having the following values:
・ Release paper E with texture: Sz = 38.83, Sa = 6.56
・ Release paper F with texture: Sz = 90.15, Sa = 12.86
・Release paper with texture G: Sz = 78.23, Sa = 13.31
- Textured release paper H: Sz = 51.19, Sa = 7.87
・Release paper with texture I: Sz = 49.35, Sa = 8.72
・ Release paper with texture J: Sz = 57.05, Sa = 8.18
・ Release paper K with texture: Sz = 47.82, Sa = 7.29
・ Release paper L with texture: Sz = 73.71, Sa = 6.76

Further, the polyurethane solution used for forming the resin layer used in this example will be described below.
Polyurethane solution M: A polyurethane solution obtained by dissolving a polyether-polyester polyurethane resin in a mixed solvent of ethyl acetate and N,N-dimethylformamide (DMF) and adding a pigment.
Polyurethane N: Polyurethane solution in which a polycarbonate-based polyurethane resin is dissolved in DMF, a solvent, and a pigment is added.

[Example 1]
A polyurethane solution M was applied to the surface of the textured release paper E and dried at 80° C. for 10 minutes to form a polyurethane skin layer having a thickness of 30 μm. Next, a layer corresponding to the intermediate layer having a thickness of 30 μm was formed on the polyurethane skin layer by the same procedure. Then, on the surface of the formed polyurethane skin layer/intermediate layer, a polyether-ester non-yellowing type one-liquid curable polyurethane solution that serves as an adhesive layer is further applied and dried at 50°C for 3 minutes to obtain a thick layer. An adhesive layer with a thickness of 40 μm was formed. Thus, a resin layer having a thickness of about 100 μm was formed. The 100% modulus of the resin layer was 27 MPa.

Then, the adhesive layer of the resin layer formed on the surface of the textured release paper E was adhered to one surface of the fiber base material A, and heated at 80° C. for 2 minutes. In this way, a leather-like sheet of artificial leather having a thickness of 446 μm and having a resin layer with a grain finish was obtained. Then, the obtained leather-like sheet was evaluated according to the evaluation method described above. Table 1 shows the results.

[Examples 2 to 9, Comparative Examples 1 to 4]
A leather-like sheet was prepared in the same manner as in Example 1 except that the fiber base material and the textured release paper shown in Table 1 were used instead of the fiber base material A and the textured release paper E in Example 1. obtained and evaluated. Table 1 shows the results.

Referring to Table 1, the maximum value T1 of 20% strength is 4 kg / 2.5 cm or more, and the area of the top of the region corresponding to 80% or more of the maximum height Sz of the surface of the resin layer is the total area. The leather-like sheets of Examples 1 to 9, which were in the range of 25 to 65%, all showed a static friction coefficient of 0.55 or more on the surface of the resin layer, showing high frictional resistance. On the other hand, the leather-like sheets obtained in Comparative Examples 1 to 3, in which the top area of the region corresponding to 80% or more of the maximum height Sz was 25% or less of the total area, had a maximum value T1 of 4 kg/2. Even if the thickness was 5 cm or more, the coefficient of static friction on the surface of the resin layer was less than 0.55, and the frictional resistance was low. In addition, even if the area of the region top corresponding to 80% or more of the maximum height Sz was 25% or more of the total area, the maximum value T1 was less than 4 kg/2.5 cm. The leather-like sheet also had a static friction coefficient of less than 0.55 on the surface of the resin layer, indicating a low frictional resistance.

1 fiber base material 2 resin layer 2a embossed uneven surface 10 leather-like sheet (decorative layer)
40 Decorative molding

Claims (7)

A leather-like sheet in which a resin layer mainly composed of an elastic polymer is coated on one surface of a fiber base material,
The maximum value T1 of 20% strength at 20 ° C. is 4 kg / 2.5 cm or more,
The surface of the resin layer has an embossed uneven surface, and the area of the region corresponding to 80% or more of the maximum height Sz in the surface roughness measurement according to ISO 25178 is 25 to 65% of the total area. A leather-like seat characterized by 2. The leather-like sheet according to claim 1, wherein said elastic polymer is polyurethane. 3. The leather-like sheet according to claim 1, wherein the coefficient of static friction of the surface of the resin layer is 0.55 or more. The leather-like sheet according to any one of claims 1 to 3, wherein the maximum height Sz of the embossed uneven surface is 30 to 100 µm. The leather-like sheet according to any one of claims 1 to 4, wherein the fiber base material has a maximum value T2 of 20% strength at 20°C of 2.5 kg/2.5 cm or more. 6. The ratio T2/T1 of the maximum 20% tenacity T2 of the fiber base material to the maximum 20% tenacity T1 of the leather-like sheet is 0.5 to 2.0. The leather-like sheet described in . A decorated molded body comprising a resin molded body and a decorative layer attached to the surface of the resin molded body,
A decorated molded article, wherein the decorative layer is the leather-like sheet according to any one of claims 1 to 6.

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