Surface material

Abstract

The objective is to provide a surface material that possesses both SG (stable protective) and SR (stable protective) properties, while also having suppressed surface gloss. [Solution] A surface material laminated in the order of at least a resin layer and a surface treatment layer, wherein the surface treatment layer consists of at least two layers: a first surface treatment layer that forms the outermost surface of the surface material and a second surface treatment layer provided on the resin layer side of the first surface treatment layer, the first surface treatment layer is formed of at least a water-based polyurethane resin, a crosslinking agent, a silicone compound and a hydrophilic polyester compound, and the second surface treatment layer is formed of at least a water-based polyurethane resin, a crosslinking agent and a matting agent.

Description

[Technical Field]

[0001] This invention relates to a surface material that has excellent stain resistance and suppressed surface gloss. [Background technology]

[0002] Surface treatment layers are used in various fields, such as automotive interior materials and furniture surface components. The surface treatment layer is provided to improve the abrasion resistance of the surface material and to adjust its appearance, including color, gloss, and sheen.

[0003] In addition to the above, the surface treatment layer is also required to have antifouling properties. Antifouling properties can be broadly classified into two types: properties that make it difficult for dirt to adhere in the first place (SG properties) and properties that allow dirt to be easily wiped off with water or other means even if it does adhere (SR properties). Japanese Patent Publication No. 2023-94122 (Patent Document 1) discloses a surface treatment agent containing an aqueous polyurethane resin, an acrylic resin, a fluorine-containing compound, and a hydrophilic compound, which is described as having both SG and SR properties. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-94122 [Overview of the project] [Problems that the invention aims to solve]

[0005] Incidentally, in recent years, surface materials, particularly those used in vehicle interiors and furniture, have seen a trend towards preferring a less glossy surface and a more luxurious or substantial appearance. According to the inventors' research, it was found that surface materials having SG and SR properties as exemplified in Patent Document 1 tend to have a higher surface gloss the more sufficient their dirt-removing performance is. While it is known that a matting agent can be included to suppress surface gloss, the inclusion of a matting agent tends to impair SG (seal protection) and SR (seal resistance) properties. Therefore, it has been difficult to provide a surface material that possesses both SG and SR properties while suppressing surface gloss.

[0006] This invention has been made in view of the above-mentioned problems. Specifically, the object of this invention is to provide a surface material that has SG and SR properties, as well as suppressed surface gloss. [Means for solving the problem]

[0007] The present invention relates to a surface material laminated in the order of at least a resin layer and a surface treatment layer, wherein the surface treatment layer consists of at least two layers: a first surface treatment layer that forms the outermost surface of the surface material and a second surface treatment layer provided on the resin layer side of the first surface treatment layer, the first surface treatment layer is formed from at least a water-based polyurethane resin, a crosslinking agent, a silicone compound, and a hydrophilic polyester compound, and the second surface treatment layer is formed from at least a water-based polyurethane resin, a crosslinking agent, and a matting agent. [Effects of the Invention]

[0008] The surface material of the present invention having the above configuration provides a surface material that is excellent in SG properties and SR properties, and has suppressed surface gloss. [Modes for carrying out the invention]

[0009] The surface material of the present invention is formed by laminating a resin layer and a surface treatment layer in that order. The surface treatment layer consists of a first surface treatment layer that forms the outermost surface of the surface material and a second surface treatment layer formed on the resin layer side of the first surface treatment layer. It consists of at least two layers of surface treatment. The surface material of the present invention may be in the form of a so-called resin sheet, composed of a resin layer and a surface treatment layer, or it may be in the form of a so-called synthetic leather, in which a fibrous fabric base material is arranged on the back surface of the resin layer (the surface opposite to the surface on which the surface treatment layer is formed). Here, we will explain using the form of synthetic leather as an example.

[0010] [Textile fabric base material] The fibrous fabric base material may be any fabric material that utilizes fibers, such as knitted fabric, woven fabric, or nonwoven fabric. The fibers forming the fibrous fabric base material are not particularly limited and can include synthetic fibers, natural fibers, etc. Examples of synthetic fibers include polyester, polyamide, acrylic, and nylon, but are not limited to these. Examples of natural fibers include cotton, linen, and rayon. The thickness of the fibrous fabric base material is not particularly limited, but considering the mechanical strength and texture of the surface material, it is preferably 100 μm to 2000 μm, and more preferably 300 μm to 1000 μm. The basis weight of the fibrous fabric base material is also not particularly limited, but similar to the thickness, considering the mechanical strength and texture of the surface material, it is preferably 10 g / m². 2 More than 500g / m 2 Preferably, it is 20 g / m 2 More than 300g / m 2 The following is more preferable:

[0011] [Resin layer] The resin layer is a layer having at least an epidermal layer. The resin layer may be constructed by laminating the surface layer and adhesive layer in that order from the surface side, or an intermediate layer may be interposed between the surface layer and the adhesive layer. The intermediate layer may be a single layer or a multilayer structure of two or more layers.

[0012] Any resin that can be used for the resin layer of a surface material can be used as the resin constituting the surface layer, but polyurethane resin or vinyl chloride resin is preferred.

[0013] As the above-mentioned polyurethane resin, any resin can be used as long as it can be used in the skin layer of the skin material. Specifically, polyester-based polyurethane resin, polyether-based polyurethane resin, polycaprolactone-based polyurethane resin, polyester / polyether copolymer-based polyurethane resin, polyamino acid / polyurethane copolymer resin, non-yellowing polycarbonate-based polyurethane resin obtained by reacting a polycarbonate diol component with a non-yellowing diisocyanate component and a low molecular chain extender, etc. can be mentioned. Further, as long as the physical properties as the skin material are not impaired, polyvinyl chloride resin, synthetic rubber, etc. may be mixed with the above-mentioned polyurethane resin.

[0014] As the above-mentioned vinyl chloride resin, any resin can be used as long as it can be used in the skin layer of the skin material. Specifically, polyvinyl chloride, a copolymer of vinyl chloride monomer and other monomers copolymerizable therewith, or a blend of these resins, etc. can be used. Examples of other monomers copolymerizable with the above-mentioned vinyl chloride monomer include ethylene, propylene, vinyl acetate, vinylidene chloride, acrylic acid, acrylic ester, methacrylic acid, methacrylic ester, maleic acid, fumaric acid, acrylonitrile, etc.

[0015] When the skin layer is composed of a vinyl chloride resin, a plasticizer is blended together with the vinyl chloride resin in order to more effectively exhibit flexibility similar to natural leather. Examples of the plasticizer include general phthalic acid ester-based plasticizers represented by dioctyl phthalate (DOP), diisononyl phthalate (DINP), butyl benzyl phthalate (BBP), diisodecyl phthalate (DIDP), diundecyl phthalate (DUP), etc., dioctyl adipate (DOA), dioctyl sebacate (DOS), azel Examples include general fatty acid ester plasticizers such as dioctyl leuate (DOZ), trimellitate trioctyl ester plasticizers, adipic acid polyester plasticizers such as polypropylene adipate, sebaciate plasticizers, and phosphate ester plasticizers such as tricresyl phosphate (TCP), trixylenyl phosphate (TXP), tris(isopropylphenyl) phosphate, tributyl phosphate, triethyl phosphate, triphenyl phosphate, and triethylphenyl phosphate.

[0016] The thickness of the epidermal layer is not particularly limited, but it is preferably formed to a thickness of 10 μm to 500 μm, and more preferably to a thickness of 10 μm to 400 μm.

[0017] The resin constituting the intermediate layer can be any resin that can be used for the resin layer of the surface material, similar to the surface layer, but polyurethane resin or polyvinyl chloride resin is preferred. Specific examples of polyurethane resin and polyvinyl chloride resin are the same as those for the surface layer described above. Furthermore, the intermediate layer may be a foamed layer or a non-foamed layer. Methods for foaming the intermediate layer include physical foaming by mechanical stirring, chemical foaming by adding a foaming agent, and pseudo-foaming by adding hollow microparticles. The foam layer is preferably a polyurethane foam layer or a polyvinyl chloride foam layer.

[0018] The adhesive layer is a layer provided to improve the adhesion between the synthetic resin layer, such as the skin layer, and the fibrous fabric base material. The resin constituting the adhesive layer can be any resin that can be used for the resin layer of the skin material, similar to the skin layer and intermediate layer, but polyurethane resin or polyvinyl chloride resin is preferred. Specific examples of polyurethane resin and polyvinyl chloride resin are the same as those for the skin layer described above. Furthermore, the adhesive layer may be a foamed layer or a non-foamed layer. The means of making the adhesive layer a foamed layer is the same as the means of making the intermediate layer a foamed layer as described above.

[0019] The resin compositions constituting the surface layer, intermediate layer, and adhesive layer may contain various additives such as pigments, fillers, dispersants, defoamers, matting agents, and lubricants, to the extent that they do not impair the physical properties of each component.

[0020] [Surface treatment layer] The surface treatment layer consists of at least two layers: a first surface treatment layer that forms the outermost surface of the surface material, and a second surface treatment layer that is provided on the resin layer side of the first surface treatment layer.

[0021] (First surface treatment layer) The first surface treatment layer, which forms the outermost surface of the surface material, contains at least a water-based polyurethane resin, a crosslinking agent, a silicone compound, and a hydrophilic polyester compound.

[0022] <Water-based polyurethane resin> Water-based polyurethane resin refers to polyurethane resin that is soluble in or emulsifiable in water. A polyurethane resin that is soluble in water refers to a polyurethane resin that has hydrophilic groups. Such a polyurethane resin is also called a self-emulsifying water-based polyurethane resin. Examples of such water-based polyurethane resins include polyurethane resins that have hydrophilic groups (anionic hydrophilic groups, cationic hydrophilic groups, nonionic hydrophilic groups) in their molecules, or polyurethane resins to which hydrophilic segments have been added.

[0023] Furthermore, a polyurethane resin that can be emulsified in water refers to a polyurethane resin that has been made dispersible in water by being encapsulated with a surfactant. This is also called a forced-emulsification type water-based polyurethane resin. Generally, polyurethane resins that can be emulsified in water are hydrophobic polyurethane resins.

[0024] The surfactant used to obtain a polyurethane resin that can be emulsified in water is one or more selected from anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, polymeric surfactants, and reactive surfactants. Examples of anionic surfactants include higher fatty acids, resin acids, acidic fatty alcohols, sulfate esters, higher alkyl sulfonates, alkylallyl sulfonates, sulfonated castor oil, and sulfosuccinate esters. Other examples of nonionic surfactants include known reaction products of ethylene oxide with long-chain fatty alcohols or phenols.

[0025] The polyurethane contained in the aqueous polyurethane resin is formed by reacting a polyurethane raw material composition containing a polyol component, an isocyanate component, and a crosslinking agent. The polyurethane contained in the aqueous polyurethane resin can be produced by known methods for producing polyurethane. Polyurethanes included in water-based polyurethane resins include polycarbonate-based polyurethanes, polyether-based polyurethanes, polyester-based polyurethanes, and variants thereof. However, from the viewpoint of durability, abrasion resistance, and hydrolysis resistance, polycarbonate-based polyurethanes are preferred. Polycarbonate-based polyurethanes can be obtained, for example, by polyaddition reaction using polycarbonate-based diols and polyisocyanates.

[0026] Furthermore, the water-based polyurethane resin used in the present invention can be appropriately selected from commercially available products. Examples of commercially available products include, but are not limited to, Rackcoat WN157M (manufactured by Seiko Chemicals Ltd., a water-based polycarbonate polyurethane).

[0027] <Crosslinking agent> The crosslinking agent included in the first surface treatment layer is exemplified by one or more selected from the group consisting of isocyanate-based crosslinking agents, carbodiimide-based crosslinking agents, and oxazoline-based crosslinking agents. The above crosslinking agents are used to improve the physical properties of the water-based polyurethane resin.

[0028] <Silicone resin> The first surface treatment layer contains a silicone-based compound. The inclusion of a silicone-based compound imparts SG properties to the surface material. The silicone compound may be any of the following: straight silicone, modified silicone, or acrylic-silicone copolymer. Examples of straight silicones include dimethyl silicone (i.e., polydimethylsiloxane), methylphenyl silicone, and methylhydrogen silicone. Examples of modified silicones include acrylic-modified silicone and epoxy-modified silicone. Examples of acrylic-silicone copolymers include copolymers of poly(meth)acrylic acid esters such as polymethyl methacrylate and polydimethylsiloxane.

[0029] <Hydrophilic polyester compounds> The first surface treatment layer contains a hydrophilic polyester compound. By including a hydrophilic polyester compound, it becomes possible to impart SR properties to the surface material, allowing dirt to be easily removed by wiping with water. Furthermore, hydrophilic polyester compounds are suitable for the present invention because they do not easily produce gloss, thus suppressing surface gloss while imparting SR properties. The hydrophilic polyester compounds used in the present invention are polyvalent carboxylic acid component units or The hydrophilic polyester copolymer contains ester-forming derivative component units and polyhydric alcohol component units, and it is preferable that the hydrophilic polyester copolymer has an aromatic ring in its chain unit. Examples of hydrophilic polyester copolymers having an aromatic ring include copolymers of aromatic polycarboxylic acids or their ester-forming derivatives and polyhydric alcohols.

[0030] Examples of the aromatic polycarboxylic acid include terephthalic acid, isophthalic acid, orthophthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, and 2,6-naphthalenedicarboxylic acid. Examples of ester-forming derivatives of the aromatic polycarboxylic acid include lower alkyl esters of the aromatic polycarboxylic acid (e.g., methyl esters, ethyl esters, propyl esters, dibutyl esters, etc.), salts of the aromatic polycarboxylic acid (e.g., chlorides, etc.), and phthalic anhydride.

[0031] Furthermore, an aromatic polycarboxylic acid having a sulfonic acid base may be used as the aromatic polycarboxylic acid. Examples of aromatic polycarboxylic acids having a sulfonic acid base include sulfonic acid metal salts (preferably sodium salts and potassium salts) of aromatic dicarboxylic acids having a sulfonic acid group (for example, sulfoterephthalic acid, 5-sulfoisophthalic acid, 4-sulfophthalic acid, 5-sulfoisophthalic acid, 4-sulfonaphthalene-2,7-dicarboxylic acid, 5-(4-sulfophenoxy)isophthalic acid, etc.), and sulfonic acid metal salts (preferably sodium salts and potassium salts) of lower alkyl esters of the aromatic dicarboxylic acids having a sulfonic acid group.

[0032] Such aromatic polycarboxylic acids (including aromatic polycarboxylic acids having a sulfonic acid base) and their ester-forming derivatives may be used individually or in combination of two or more. Furthermore, from the viewpoint of improving the water solubility or emulsification dispersibility of the hydrophilic polyester copolymer and the stain-resistant performance of the leather, it is more preferable to use aromatic polycarboxylic acids without a sulfonic acid base and aromatic polycarboxylic acids having a sulfonic acid base in combination.

[0033] Examples of the aforementioned polyhydric alcohols include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3-butylene glycol, 1,4-butylene glycol, 2-methyl-1,3-propylene glycol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, and 2,2-dimethyl-3-hydroxypropyl-2,2' -Dimethyl-3-hydroxypropane, 2-n-butyl-2-ethyl-1,3-propanediol, 3-ethyl-1,5-pentanediol, 3-propyl-1,5-pentanediol, 2,2-diethyl-1,3-propanediol, 3-octyl-1,5-pentanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, polyethylene glycol with a molecular weight of 300 to 10000, aliphatic diols such as random or block copolymers of ethylene oxide and propylene oxide; 1,3-bis(hydro (Xymethyl)cyclohexane, 1,4-bis(hydroxymethyl)cyclohexane, 1,4-bis(hydroxyethyl)cyclohexane, 1,4-bis(hydroxypropyl)cyclohexane, 1,4-bis(hydroxymethoxy)cyclohexane, 1,4-bis(hydroxyethoxy)cyclohexane, 2,2-bis(4-hydroxymethoxycyclohexyl)propane, 2,2-bis(4-hydroxyethoxycyclohexyl)propane, bis(4-hydroxycyclohexyl)methane, 2,2-bis(4-hydroxycyclohexyl)propane, 3(4),8(9)-tricyclo[5.2.1.0 2,6 Examples include alicyclic diols such as decanedimethanol; aromatic diols such as bishydroxyethoxybenzene, bisphenol A, bisphenol S, and hydroquinone; and alkylene oxide adducts thereof. These polyhydric alcohols may be used individually or in combination of two or more. Furthermore, among such polyhydric alcohols, diols having oxyethylene groups, such as polyethylene glycol, are preferred from the viewpoint that the emulsified dispersion of hydrophilic polyester copolymer is stable over time.

[0034] The weight-average molecular weight of the hydrophilic polyester compound is preferably 1,000 to 200,000, and more preferably 10,000 to 50,000. If the weight-average molecular weight of the hydrophilic polyester compound falls below the lower limit, the SR properties of the surface material may not be fully exhibited. On the other hand, if it exceeds the upper limit, the viscosity of the hydrophilic polyester compound may become too high, making it difficult to handle.

[0035] Examples of commercially available hydrophilic polyester compounds include Nicepole PR-99, Nicepole PR-9000, Nicepole PRK-60 (all manufactured by Nikka Chemical Co., Ltd.), and Hydroperm NIOPOs (manufactured by Archroma).

[0036] <Acrylic resin> The first surface treatment layer preferably contains an acrylic resin. By including an acrylic resin, a surface treatment layer with a high contact angle with water is formed, which further imparts SG properties to the surface material. Therefore, even if the brightness (L value) of the surface material of the substrate is 75 or higher, that is, even if the substrate is white or otherwise prone to visible stains, the SG properties work well, exhibiting excellent stain resistance. Examples of acrylic resins include homopolymers and copolymers of acrylic monomers. Examples of acrylic monomers include (meth)acrylic acid and its derivatives, such as methyl (meth)acrylate, ethyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, (meth)acrylic acid, glycidyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, and 2-hydroxypropyl (meth)acrylate. Here, (meth)acrylic acid refers to acrylic acid or methacrylic acid. Furthermore, these acrylic monomers may be used individually or in combination of two or more.

[0037] In the first surface treatment layer, it is preferable that the water-based polyurethane resin is 5 to 60% by mass relative to 100% by mass of the total mass of the resin and organic compounds constituting the first surface treatment layer. The amount of crosslinking agent in the first surface treatment layer is preferably 5 to 20% by mass. If it is less than 5% by mass, the abrasion resistance of the first surface treatment layer may be insufficient. If it exceeds 20% by mass, the first surface treatment layer may harden and impair its texture. The silicone compound is preferably present in the first surface treatment layer at a concentration of 10 to 30% by mass. If the concentration is less than 10% by mass, the SG properties of the surface treatment layer may not be sufficient. On the other hand, if the concentration exceeds 30% by mass, it tends not to be possible to obtain further improvement in SG properties. The hydrophilic polyester compound is preferably present in the first surface treatment layer at a concentration of 10 to 40% by mass. If the concentration is less than 10% by mass, the SR (Surface Resistance) properties may not be sufficient. On the other hand, even if the concentration exceeds 40% by mass, further improvement in SR properties tends to be difficult to achieve. When acrylic resin is included in the first surface treatment layer, it is preferable that the amount in the first surface treatment layer be 20 to 70% by mass. If it is less than 20% by mass, the SG property improvement effect may not be observed. On the other hand, if it exceeds 70% by mass, it tends to become more difficult to suppress surface gloss.

[0038] The basis weight of the first surface treatment layer is 2-20 g / m². 2 Preferably, it is 2 g / m². 2 If the amount is less than 20 g / m², the SG and SR properties may not be fully realized. 2 Beyond a certain point, even with the application of the second surface treatment layer described later, it tends to become difficult to suppress surface gloss.

[0039] The surface material of the present invention can possess both SG and SR properties by having its outermost surface composed of a first surface treatment layer containing the above-mentioned water-based polyurethane resin, a crosslinking agent, a silicone compound, and a hydrophilic polyester compound. Furthermore, it can be made less glossy than conventional surface materials that possess both SG and SR properties. Furthermore, by incorporating an acrylic resin into the first surface treatment layer, a surface treatment layer with a high contact angle with water is formed, thereby further imparting SG properties to the surface material. As a result, even when the L value of the surface material of the substrate is 75 or higher, that is, even if the substrate is white or otherwise prone to noticeable staining, the SG properties work well, exhibiting excellent stain resistance.

[0040] (Second surface treatment layer) The second surface treatment layer is formed on the resin layer side of the first surface treatment layer, which is formed on the outermost surface of the surface material. The second surface treatment layer contains a water-based polyurethane resin, a crosslinking agent, and a matting agent. By providing this second surface treatment layer, the surface material of the present invention can exhibit a matte finish with suppressed surface gloss, while possessing both SG and SR properties.

[0041] <Water-based polyurethane resin> As the water-based polyurethane resin, the same water-based polyurethane resin as the first surface treatment layer described above is used. In the second surface treatment layer, it is preferable that the water-based polyurethane resin is 5 to 80% by mass relative to 100% by mass of the total mass of the resin and organic compounds constituting the second surface treatment layer.

[0042] <Crosslinking agent> As the crosslinking agent, one or more selected from the group consisting of isocyanate-based crosslinking agents, carbodiimide-based crosslinking agents, and oxazoline-based crosslinking agents are used, similar to the first surface treatment layer described above. In the second surface treatment layer, the amount of the crosslinking agent is preferably 2 to 20% by mass relative to 100% by mass of the total mass of the resin and organic compounds constituting the second surface treatment layer. If it is less than 2% by mass, the abrasion resistance of the second surface treatment layer may become insufficient. If it exceeds 20% by mass, the second surface treatment layer may harden and impair its texture.

[0043] <Matte agent> The second surface treatment layer contains a matting agent. The inclusion of this matting agent suppresses gloss, making it possible to form a layer with a matte finish. Examples of matting agents include organic fillers and inorganic fillers. The matting agent may be a single type of filler, or a mixture of two or more types of fillers. Examples of components that make up the organic filler include particulate matter made of urethane resins, methacrylic acid ester resins, and the like. Examples of materials that make up inorganic fillers include titanium dioxide, glass beads, calcium carbonate, aluminum powder, and mica. As a matting agent, an organic filler is preferred, and from the viewpoint of good compatibility with the water-based polyurethane that forms the second surface treatment layer, a filler made of urethane resin (urethane beads) is preferred.

[0044] The matting agent is preferably included in a proportion of 2.5 to 50% by mass, and more preferably in a proportion of 10 to 25% by mass, based on 100% by mass of the total mass of the resin and organic compounds constituting the second surface treatment layer. When the content ratio of the matting agent is less than 2.5% by mass, the effect of suppressing glossiness may not be sufficient. On the other hand, if it exceeds 50% by mass, there is a risk of whitening or difficulty in film formation.

[0045] The average particle diameter of the matting agent is not particularly limited and may be appropriately determined from the thickness of the outermost surface treatment layer, etc. For example, the average particle diameter of the matting agent is preferably 2.0 to 20 μm, and more preferably 5.0 to 15 μm. If the average particle diameter of the matting agent is less than 2.0 μm, particle aggregation may occur, and the dispersibility of the matting agent in the second surface treatment layer may deteriorate. If it exceeds 20 μm, there is a risk that the SR property and SG property may not be sufficiently exhibited.

[0046] When the second surface treatment layer contains a matting agent, minute irregularities are formed on the surface. As a result, the light that passes through the first surface treatment layer and is incident on the second surface treatment layer is diffusely reflected, and as a result, the gloss value (Gloss Unit, GU) decreases and the surface gloss is suppressed. In addition, since the minute irregularities on the surface of the second surface treatment layer are covered by the first surface treatment layer and do not appear on the outermost surface of the skin material, the SG property and SR property exhibited by the first surface treatment layer are not impaired.

[0047] The basis weight of the second surface treatment layer is preferably 5 to 20 g / m 2 . If it is less than 5 g / m 2 , there is a risk that the matting effect is insufficient. Even if it exceeds 20 g / m 2 , the improvement of the matting effect may not be expected in some cases.

[0048] The gloss value (Gloss Unit, GU) of the skin material is not particularly limited. However, when the lightness (L value) of the skin material exceeds 70, it is preferably 3.2 or less; when the lightness (L value) is 50 to 70, it is preferably less than 2.5; and when the lightness (L value) is less than 50, it is preferably 1.8 or less. By the gloss value of the skin material being within the above range, the surface gloss is suppressed, and a skin material excellent in a sense of luxury and a sense of solidity can be provided.

[0049] When the lightness (L value) of the surface material is 50 to 70, the color difference ΔE1 (SG property) before and after the stain adhesion work, calculated by the method described in the examples below, is preferably 3.5 or less, and more preferably 2.0 or less. Furthermore, if the lightness (L value) of the surface material exceeds 70, it is preferable that the color difference ΔE1 (SG property) before and after the stain adhesion work, calculated by the method described in the examples below, be less than 8.0, and more preferably 5.0 or less. As long as the color difference ΔE1 (SG property) of the surface material is within the above range, the SG property works well even if the brightness of the surface material is in a range that differs, and a surface material with excellent stain resistance can be provided.

[0050] In relation to the present invention, the gloss value (Gloss Unit, GU) can be measured using a commercially available gloss meter. The surface material of the present invention is preferably measured at an incident angle of 60 degrees.

[0051] As described above, the surface material of the present invention has a first surface treatment layer comprising a water-based polyurethane resin, a crosslinking agent, a silicone compound, and a hydrophilic polyester compound, making it possible to impart SG properties and SR properties. Furthermore, the second surface treatment layer contains a matting agent and forms minute irregularities on its surface. As a result, light that passes through the first surface treatment layer and enters the second surface treatment layer is diffusely reflected, leading to a decrease in gloss value and suppression of surface gloss. In addition, the minute irregularities on the surface of the second surface treatment layer are covered by the first surface treatment layer and do not appear on the outermost surface of the surface material, thus not impairing the SG and SR properties provided by the first surface treatment layer. Therefore, it becomes possible to provide a surface material that possesses both SG and SR properties while suppressing surface gloss.

[0052] In this invention, a silicone-based compound was adopted to impart excellent SG properties to the surface material while keeping costs and environmental impact low and without impairing the texture of the surface material. However, this usually tends to cause phase separation with the water-based polyurethane resin, which is the base resin constituting the first and second surface layers, due to the difference in polarity between the two, resulting in a problem of not being able to form a uniform surface layer. Therefore, we conceived and searched for a compound that could eliminate the phase separation between the water-based polyurethane resin and the silicone-based compound, be compatible with the water-based polyurethane resin and the silicone-based compound to form a uniform surface layer, and also impart excellent SR properties to the surface material. We found that a hydrophilic polyester-based compound has high affinity with the water-based polyurethane resin, plays a role in mediating compatibility with the silicone-based compound, and can also impart SR properties to the surface material. Therefore, this invention makes it possible to impart both excellent SG and SR effects to the surface material of the present invention by adopting four components in its composition: a water-based polyurethane resin, a silicone-based compound, a hydrophilic polyester-based compound, and a crosslinking agent that improves the physical properties of the water-based polyurethane resin.

[0053] The first surface treatment layer may contain components other than the four components mentioned above, as long as they do not impair the effects of the present invention. For example, it may contain a matting agent if the SG and SR properties of the surface material are exhibited to the desired extent. By including a matting agent in the first surface treatment layer, the surface gloss can be further suppressed in combination with the matting agent in the second surface treatment layer. The matting agent to be included in the first surface treatment layer can be the same as that described above under <Matting Agent>. The proportion of the matting agent can also be the same.

[0054] The applications of the surface material of the present invention are not particularly limited, but for example, it can be used as an interior material for vehicles that covers surfaces such as seats and dashboards, or as a surface material that covers surfaces such as furniture, clothing, bags, or stationery. In particular, since the present invention can provide a high-quality or substantial appearance with suppressed surface gloss, it is preferably used as an interior material for vehicles. [Examples]

[0055] A synthetic leather (laminated body 1) with a brightness (L value) of 63 and a beige color was prepared, consisting of a polyester knitted fabric with an average thickness of 500 μm, on one side, with an adhesive layer, an intermediate layer, and an epidermal layer laminated in that order. The above adhesive layer was designed to have a thickness of 50 μm using an adhesive primarily composed of polyester polyurethane resin. The above-mentioned intermediate layer was a foamed polyvinyl chloride layer with an average thickness of 300 μm. The above-mentioned epidermal layer was a polyvinyl chloride layer with an average thickness of 200 μm.

[0056] In the above-mentioned base material 1, the pigment in the epidermal layer was changed to prepare a white synthetic leather (laminated body 2) with a lightness (L value) of 85.

[0057] (Examples 1-5) The first and second surface treatment layer compositions were prepared according to the formulations shown in Tables 1 and 2. A dry thickness of 15 g / m² was obtained by applying a reverse coater to the surface layer of laminate 1 or laminate 2. 2 A second surface treatment layer composition was applied to form the second surface treatment layer. After drying, the second surface treatment layer was coated with a reverse coater to a dry thickness of 8 g / m². 2 The first surface treatment layer composition was applied to form the first surface treatment layer, and a surface material comprising the first surface treatment layer and the second surface treatment layer was created, which were designated as Examples 1 to 5.

[0058] (Comparative Examples 1-6) Laminates 1 and 2 were prepared in the same manner as in the above examples, and a surface material having a first surface treatment layer and a second surface treatment layer was prepared in the same manner as in Examples 1 to 5, and Comparative Examples 1 to 6 were prepared accordingly. In Comparative Example 1, the first surface treatment layer was applied directly to the surface layer without forming a second surface treatment layer, while in Comparative Examples 5 and 6, the first surface treatment layer was not provided, and the second surface treatment layer was the outermost surface.

[0059] The details of the compositions used in the examples and comparative examples are as follows. Note that the compositional values ​​for the first and second surface treatment layers in Tables 1 and 2 represent mass % (solids). <Water-based polyurethane resin> • Water-based polycarbonate polyurethane: Rackcoat WN157M, manufactured by Seiko Chemical Co., Ltd. <Crosslinking agent> • Carbodiimide crosslinking agent: Laccoat CL7070, manufactured by Seiko Chemical Co., Ltd. <Silicone-based compounds> • FE-502, manufactured by Shin-Etsu Chemical Co., Ltd. <Hydrophilic polyester compounds> • PR99, manufactured by Nikka Chemical Co., Ltd. <Acrylic resin> • UH-2041, manufactured by Toagosei Co., Ltd. <Matte agent> • Acrylic beads: C-800, manufactured by Negami Kogyo Co., Ltd.

[0060] The examples and comparative examples obtained as described above were tested and evaluated as follows. The measured values ​​and evaluations in the tests are shown in Tables 1 and 2.

[0061] (Dirt accumulation) The surface material obtained in the examples and comparative examples was cut to a diameter of 150 mm to obtain test specimens. Next, the test specimens were set in a Martindale testing machine, a water-soaked artificial soil cloth (Denim2550Y) was cut to a diameter of 30 mm and attached to the friction element, and a load of 12 kPa was applied, and friction was performed for 300 rotations in linear reciprocating mode to adhere the dirt to the test specimens (Condition 1).

[0062] (Wipe away dirt) The above-mentioned test piece, which had dirt attached to it, was mounted on a flat abrasion tester, a bath towel (JIS L 4105 3a No. 1) moistened with water was attached to the friction element, and the dirt was wiped off 100 times while applying a load of 9.8 N (Condition 2).

[0063] (Measurement of color difference ΔE) The hue was measured using a colorimeter (Konica Minolta, Inc., spectrophotometer CM-250d, light source D65), and the color difference ΔE was calculated. (Evaluation of SG characteristics) The ΔE1 of the test specimen after applying dirt (Condition 1) was calculated. (Evaluation of SR characteristics) The ΔE2 of the test specimen after wiping off the dirt (Condition 2) was calculated. <Method for calculating color difference ΔE> The hue (L1, a1, b1) of the surface material was measured at three points before the dirt application process, and the average value was calculated. Then, after the dirt application process and after the wiping process, the hue (after dirt application: L2, a2, b2 / after wiping: L3, a3, b3) of the surface material was measured at three points, and the average value was calculated. The differences in color intensity and hue after the staining process, ΔL1, Δa1, and Δb1, were calculated using the following equations (1) to (3). ΔL1 = L2 - L1·····(1) Δa1 = a2 - a1 ·····(2) Δb1 = b2 - b1 ·····(3) Then, the color difference ΔE1 for (Condition 1) was calculated based on the CIE1976 color difference calculation formula (4) shown below. ΔE1=[(ΔL1) 2 +(Δa1) 2 +(Δb1) 2 ] 1 / 2 ...(4) Furthermore, the difference ΔL2, Δa2, and Δb2 between the color intensity and hue before the dirt application process and the color intensity and hue after the wiping process were calculated using the following equations (5) to (7). ΔL2 = L3 - L1 ·····(5) Δa² = a³ - a¹·····(6) Δb2 = b3 - b1 ·····(7) Then, the color difference ΔE2 for (Condition 2) was calculated based on the CIE1976 color difference calculation formula (8) shown below. ΔE2=[(ΔL2) 2 +(Δa2) 2 +(Δb2) 2 ] 1 / 2...(8)

[0064] (Evaluation of glossiness) Using a gloss meter (PG-1 portable gloss meter manufactured by Nippon Denshoku Industries Ltd.), the gloss (gloss value; Gloss Unit, GU) of the outermost surface treatment layer in each example and comparative example was measured with the incident angle set to 60 degrees.

[0065] Table 1 shows an example using laminate 1 (color: beige), and Table 2 shows an example using laminate 2 (color: white).

[0066] [Table 1]

[0067] [Table 2]

[0068] The surface materials of Examples 1 and 2 were shown to have excellent SG properties and SR properties, as well as suppressed surface gloss. In particular, the surface material of Example 1 was shown to have extremely excellent SG properties by incorporating an acrylic resin in the first surface treatment layer. Furthermore, the surface material of Example 3, which contained a matting agent in the first surface treatment layer, showed a slight decrease in SG properties compared to the surface material of Example 1, but still had excellent SG properties and was shown to suppress gloss even further. The surface material of Example 4, being a white laminate (synthetic leather), was shown to have good SG and SR properties despite inherently being difficult to impart stain resistance to. Furthermore, the surface material of Example 5, which contained a matting agent in the first surface treatment layer, showed a slight decrease in SG properties compared to the surface material of Example 4, but still possessed excellent SG properties and was shown to further suppress gloss.

Claims

1. A surface material laminated in the order of at least a resin layer and a surface treatment layer, The surface treatment layer consists of at least two layers: a first surface treatment layer that forms the outermost surface of the surface material, and a second surface treatment layer that is provided on the resin layer side of the first surface treatment layer. The first surface treatment layer is formed from at least a water-based polyurethane resin, a crosslinking agent, a silicone compound, and a hydrophilic polyester compound. The second surface treatment layer is characterized by being formed from at least a water-based polyurethane resin, a crosslinking agent, and a matting agent.

2. The surface material according to claim 1, characterized in that the first surface treatment layer contains an acrylic resin.

3. The surface material according to claim 1, further comprising a matting agent in the first surface treatment layer.

Images