JP6651060B2 - Laminated sheet - Google Patents

Description

  The present invention relates to a laminated sheet using a carbonaceous substrate.

  The carbonaceous substrate is lightweight and has excellent strength. For this reason, carbonaceous substrates are used in various fields such as the aviation field, the space field, the motorcycle field, the automobile field, the construction field, the civil engineering field, the sports field and the leisure field.

  The surface of the carbonaceous substrate is generally black. In order to enhance the design of the carbonaceous substrate, the carbonaceous substrate may be colored.

A colored carbonaceous substrate is disclosed in Patent Document 1 below. Patent Document 1 listed below discloses a carbon fiber having a lightness L ^* of 20 or more in an L ^* a ^* b ^* color system measured using a reflection spectrum in the visible region at an incident angle of 60 degrees and a light receiving angle of 45 degrees ( (A colored carbonaceous substrate). In Patent Literature 1, a paint containing a pigment or a dye is used for coloring.

JP 2010-229587 A

  When a paint containing a pigment or a dye is applied to the surface of the carbonaceous substrate, a colored layer is formed on the surface of the carbonaceous substrate. As a result, the glossiness of the carbonaceous substrate may be impaired at the portion where the surface of the carbonaceous substrate is covered with the colored layer. In addition, the unique design of the carbonaceous substrate may be impaired.

  By forming a metal layer on the surface of the carbonaceous substrate, a metallic luster may be imparted. However, the mere formation of the metal layer may change the color of the metal layer and change the color tone of the metal layer. When the metal layer is exposed to a high temperature or exposed to the air for a long period of time, the color of the metal layer may change, and the color tone of the metal layer may change.

  An object of the present invention is to provide a laminated sheet capable of imparting a good metallic luster while suppressing the change in color tone while maintaining the design of the surface of the carbonaceous substrate.

  According to a broad aspect of the present invention, a carbonaceous substrate, a metal layer disposed on a surface of the carbonaceous substrate, and disposed on a surface of the metal layer opposite to the carbonaceous substrate And a metal oxide layer.

  In a specific aspect of the laminated sheet according to the present invention, the metal element contained in the metal layer is titanium, silver, or aluminum.

  In a specific aspect of the laminated sheet according to the present invention, the average thickness of the metal oxide layer is 3 nm or more.

  In a specific aspect of the laminated sheet according to the present invention, the average thickness of the metal oxide layer is less than 40 nm.

In a specific aspect of the laminated sheet according to the present invention, the metal oxide contained in the metal oxide layer is TiO ₂ or SiO ₂ .

  ADVANTAGE OF THE INVENTION According to this invention, the laminated sheet which can give favorable metallic glossiness and can suppress the change of a color tone can be provided, leaving the design property of the surface of a carbonaceous base material.

FIG. 1 is a sectional view schematically showing a laminated sheet according to the first embodiment of the present invention.

  Hereinafter, the present invention will be described in detail.

  The laminated sheet according to the present invention is a carbonaceous substrate, a metal layer disposed on the surface of the carbonaceous substrate, and disposed on the surface of the metal layer opposite to the carbonaceous substrate. And a metal oxide layer. In the laminated sheet according to the present invention, the color tone may be changed on the metal layer and the metal oxide layer side in some cases. Therefore, in this specification, a layer in which the metal layer and the metal oxide layer are stacked may be referred to as a color adjustment layer. The laminated sheet according to the present invention includes a carbonaceous substrate and a color tone adjustment layer disposed on a surface of the carbonaceous substrate. In the laminated sheet according to the present invention, the color tone adjustment layer includes a metal layer (a second color tone adjustment layer) on the carbonaceous substrate side and a metal oxide layer (a second layer) on the side opposite to the carbonaceous substrate side. 1 color tone adjusting layer). In the laminated sheet according to the present invention, the carbonaceous substrate, the metal layer, and the metal oxide layer are laminated in this order. The laminated sheet according to the present invention has a first surface and a second surface opposite to the first surface. In the laminated sheet according to the present invention, the carbonaceous substrate is disposed on the first surface side of the laminated sheet, and the color tone adjustment layer is disposed on the second surface side of the laminated sheet. . In the laminated sheet according to the present invention, the carbonaceous substrate is disposed on the first surface side of the laminated sheet, and the metal oxide layer (first layer) is disposed on the second surface side of the laminated sheet. Color adjustment layer).

  In the present invention, since the above-described configuration is provided, it is possible to impart a good metallic luster while maintaining the design of the surface of the carbonaceous substrate, and further suppress a change in color tone.

  The carbonaceous substrate has a glossiness or has a surface pattern due to an uneven shape. The surface of the carbonaceous substrate is generally black. In the present invention, a metallic luster can be favorably imparted without impairing the surface pattern of the carbonaceous substrate. Further, in the present invention, the change in the color tone on the metal layer side can be suppressed.

  In the laminated sheet according to the present invention, since the above-mentioned metal layer is provided, it is possible to provide the laminated sheet with a good metallic luster. In the laminated sheet according to the present invention, since the metal oxide layer is provided, discoloration of the metal layer can be suppressed, and change in color tone of the laminated sheet on the metal layer side can be suppressed. Further, in the laminated sheet according to the present invention, since both of the metal layer and the metal oxide layer are provided, a good metallic luster is imparted while leaving the design of the surface of the carbonaceous substrate. Further, a change in color tone on the metal layer side of the laminated sheet can be suppressed.

  In the laminated sheet according to the present invention, since the metal oxide layer is provided, the color tone of the laminated sheet can be adjusted.

  Further, in the present invention, it is possible to impart an angle dependency of the color tone to the laminated sheet. Therefore, the color tone can be changed depending on the angle at which the laminated sheet is viewed.

  The mechanism for imparting a color tone such as metallic gloss to the laminated sheet according to the present invention includes (1) the effect of the color (reflection spectrum) of the metal layer, (2) the effect of light absorption by the metal oxide layer, and (3) It is considered that the influence of optical interference generated by the metal layer and the metal oxide layer is involved. The mechanism for imparting a color tone such as metallic luster to the laminated sheet according to the present invention is not limited to the above (1) to (3).

  If the metal layer is formed only on the surface of the carbonaceous substrate, the color of the metal layer may change, and the color tone of the laminated sheet on the metal layer side may change. When the metal layer is exposed to a high temperature or exposed to the air for a long time, the color of the metal layer may be further changed, and the color tone of the laminated sheet on the metal layer side may be further changed. The present inventor has found that a change in color tone on the metal layer side of the laminated sheet can be suppressed by intentionally forming a metal oxide layer on the surface of the metal layer. In the present invention, since the above-described configuration is provided, it is possible to suppress a change in color tone on the metal layer side of the laminated sheet.

  Further, by changing the average thickness of the metal oxide layer, the color tone of the second surface of the laminated sheet can be adjusted. Since the color tone can be adjusted precisely by finely adjusting the thickness of the metal oxide layer, a color tone suitable for the purpose of the user can be given to the laminated sheet.

  In the laminated sheet according to the present invention, the color tone adjusting layer may be a layer having a property of making the color tone of the second surface of the laminated sheet different from the color tone of the surface of the carbonaceous substrate. preferable. That is, in the laminated sheet according to the present invention, the color tone adjusting layer is preferably a layer that imparts a different color tone to the second surface of the laminated sheet than the surface of the carbonaceous substrate.

  The color tone adjusting layer may have light transmittance or may not have light transmittance. From the viewpoint of further retaining the design property of the surface of the carbonaceous substrate, it is preferable that the color tone adjusting layer has light transmittance. From the viewpoint of effectively imparting a metallic gloss to the laminated sheet, the color tone adjusting layer preferably does not have light transmittance.

  The metal layer may have light transmittance or may not have light transmittance. From the viewpoint of further retaining the design of the surface of the carbonaceous substrate, the metal layer preferably has light transmittance. From the viewpoint of more effectively imparting a metallic luster to the laminated sheet, the metal layer preferably does not have light transmittance.

  The metal oxide layer may have light transmittance or may not have light transmittance. From the viewpoint of further retaining the design of the surface of the carbonaceous substrate, the metal oxide layer preferably has light transmittance.

  That the color tone adjusting layer (the metal layer and the metal oxide layer) has light transmittance means that the carbonaceous material is provided on the second surface of the laminated sheet via the color tone adjusting layer (the metal layer and the metal oxide layer). This means that the surface pattern (concavo-convex shape) of the substrate is visually recognized. When the color tone adjusting layer (the metal layer and the metal oxide layer) has light transmittance, the carbonaceous material is provided on the second surface of the laminated sheet via the color tone adjusting layer (the metal layer and the metal oxide layer). It is preferable that the surface pattern (irregular shape) of the substrate is visually recognized, and it is preferable that the glossiness of the carbonaceous substrate is visually recognized via the color tone adjustment layer (metal layer, metal oxide layer).

  The phrase “the metal oxide layer has optical transparency” means that the surface pattern (concavo-convex shape) of the carbonaceous substrate or the metal layer is visually recognized via the metal oxide layer on the second surface of the laminated sheet. means. When the metal oxide layer has optical transparency, the surface pattern (irregular shape) of the carbonaceous substrate or the metal layer may be visually recognized on the second surface of the laminated sheet via the metal oxide layer. Preferably, the glossiness of the carbonaceous substrate or the metal layer is visually recognized via the metal oxide layer.

  Since the laminated sheet according to the present invention has the above performance, it is suitably used as a decorative base sheet.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a sectional view schematically showing a laminated sheet according to the first embodiment of the present invention.

  The laminated sheet 1 shown in FIG. 1 includes a carbonaceous substrate 2 and a color tone adjusting layer 3. The color tone adjusting layer 3 has a metal oxide layer (first color tone adjusting layer) 31 and a metal layer (second color tone adjusting layer) 32. The laminated sheet 1 includes a carbonaceous substrate 2, a metal oxide layer 31, and a metal layer 32. The metal layer 32 is arranged between the carbonaceous substrate 2 and the metal oxide layer 31. A metal layer 32 is disposed on the surface of the carbonaceous substrate 2. The metal oxide layer 31 is disposed on the surface of the metal layer 32 on the side opposite to the carbonaceous substrate 2.

  The metal oxide layer 31 preferably has light transmittance.

  The laminated sheet 1 has a first surface 1a and a second surface 1b on a side opposite to the first surface 1a.

  The carbonaceous substrate 2 is disposed on the first surface 1a side of the laminated sheet 1. The color tone adjusting layer 3 is arranged on the second surface 1b side of the laminated sheet 1. In the color tone adjustment layer 3, the metal oxide layer 31 is disposed on the second surface 1 b side of the laminated sheet 1, and the metal layer 32 is disposed on the second surface 1 b side of the laminated sheet 1. The carbonaceous substrate 2, the metal layer 32, and the metal oxide layer 31 are arranged in this order.

  The laminated sheet 1 includes one metal oxide layer 31 and one metal layer 32. Each of the metal oxide layer and the metal layer may be a single layer or a multilayer.

  Hereinafter, details of each layer constituting the laminated sheet will be described.

(Carbon base material)
The carbonaceous substrate is disposed in the laminated sheet on the first surface side of the laminated sheet. The material of the carbonaceous substrate is a carbonaceous material, and the carbonaceous material is generally black. As the carbonaceous material, only one kind may be used, or two or more kinds may be used in combination. The shape of the carbonaceous substrate may be a flat sheet. The carbonaceous substrate may be a woven or knitted fabric. When the shape of the carbonaceous substrate is a flat sheet, a pattern may be present on the surface of the carbonaceous substrate.

  The carbonaceous substrate generally contains 90% by mass or more and 100% by mass or less of carbon atoms in 100% by mass of the carbonaceous substrate.

  From the viewpoint of enhancing the design of the surface of the carbonaceous substrate, the carbonaceous material is preferably a carbon fiber. The carbonaceous substrate is preferably a carbon fiber substrate.

  The carbon fiber substrate is preferably a carbon fiber woven fabric, a carbon fiber knitted fabric, or a carbon fiber nonwoven fabric. As the carbon fiber substrate, only one of carbon fiber woven fabric, carbon fiber knitted fabric, and carbon fiber nonwoven fabric may be used, or two or more of them may be used in combination.

The basis weight of the carbon fiber is not particularly limited, but is preferably 50 g / m ² or more, more preferably 100 g / m ² or more, preferably 700 g / m ² or less, more preferably 500 g / m ² or less.

  The filament diameter of the carbon fiber is not particularly limited, but is preferably 1 μm or more, more preferably 2 μm or more, preferably 50 μm or less, and more preferably 20 μm or less.

  When the carbonaceous material is carbon fiber, the density of the carbon fiber is not particularly limited, but is preferably 1 fiber / inch or more, more preferably 2 fiber / inch or more, preferably 50 fiber / inch or less, and more preferably. Is less than 20 lines / inch.

  When the carbonaceous substrate is a carbon fiber woven fabric, the weaving method is not particularly limited, but is preferably a plain weave or a twill weave.

  When the carbonaceous substrate is a carbon fiber substrate, particularly when the carbonaceous substrate is a carbon fiber woven fabric, a carbon fiber knit, or a carbon fiber nonwoven fabric, the uneven shape, the pattern, and the glossiness and the like The unique design of carbon fibers can be imparted to the laminated sheet. By forming a specific color tone adjusting layer, even when the color tone adjusting layer is disposed on the surface of the carbon fiber base material, a unique design property can be visually recognized. Moreover, when the carbonaceous material is carbon fiber, a laminated sheet that is lightweight and excellent in strength can be obtained. In a preferred embodiment of the present invention, the carbon fiber substrate is preferably a carbon fiber woven fabric or a carbon fiber knitted fabric, from the viewpoint of remarkably expressing the uneven shape and pattern of the carbonaceous substrate.

  In one embodiment of the present invention, from the viewpoint of increasing the strength of the laminated sheet, the laminated sheet may be made of carbon fiber reinforced plastic. The carbon fiber reinforced plastic includes the laminated sheet. The carbon fiber reinforced plastic preferably contains the laminated sheet and plastic. The laminated sheet may be used as a material of carbon fiber reinforced plastic. The carbon fiber base material may be used as a material of a carbon fiber reinforced plastic. By using the carbon fiber base material as the material of the carbon fiber reinforced plastic, it is possible to give the carbon fiber reinforced plastic a unique design property of the carbon fiber base material such as uneven shape, pattern, and glossiness. By forming the specific color tone adjusting layer, even when the color tone adjusting layer is disposed on the surface of the carbon fiber base material, a unique design property can be visually recognized after molding the carbon fiber reinforced plastic. Further, by using the carbon fiber base material as the material of the carbon fiber reinforced plastic, it is possible to obtain a lightweight laminated sheet having excellent strength.

(Color tone adjustment layer)
The color tone adjusting layer is a layer disposed on the surface of the carbonaceous substrate. The color tone adjustment layer is disposed in the laminated sheet on the second surface side of the laminated sheet. The color tone adjusting layer is preferably a layer having a property of making the color tone of the second surface of the laminated sheet different from the color tone of the surface of the carbonaceous substrate.

  The color tone adjustment layer has a metal oxide layer and a metal layer disposed between the metal oxide layer and the carbonaceous substrate. The laminated sheet includes a metal oxide layer and a metal layer.

  From the viewpoint of imparting a good color to the laminated sheet, the color tone adjustment layer converts the spectral reflectance curve of the second surface of the laminated sheet in visible light into the spectral reflectance curve of visible light of the surface of the carbonaceous substrate. It is preferable to have a property to make it different from the reflectance curve.

  From the viewpoint of better imparting a color to the laminated sheet, the metal oxide layer converts the spectral reflectance curve of visible light of the second surface of the laminated sheet into visible light of the surface of the carbonaceous substrate. It is preferable to have a property to make it different from the spectral reflectance curve in.

  From the viewpoint of better imparting a color to the laminated sheet, the metal layer converts a spectral reflectance curve of the second surface of the laminated sheet in visible light into a spectral reflectance curve of visible light of the surface of the carbonaceous substrate. It is preferable to have a property to make it different from the reflectance curve.

  From the viewpoint of suppressing a decrease in light transmittance (for example, visible light transmittance) of the color tone adjusting layer, the color tone adjusting layer preferably does not substantially contain a pigment. From the viewpoint of suppressing a decrease in light transmittance (for example, visible light transmittance) of the color tone adjustment layer, the color tone adjustment layer preferably does not substantially contain a dye. By forming a color tone adjustment layer substantially not containing a pigment or forming a color tone adjustment layer substantially free of a dye, the second surface of the laminated sheet has a carbonaceous substrate. Unique design properties such as unevenness, surface pattern, and glossiness can be effectively prevented from being impaired. By forming a color tone adjusting layer substantially free of both pigments and dyes, the second surface of the laminated sheet has a unique design property such as unevenness, surface pattern, and glossiness of the carbonaceous substrate. Is more effectively prevented from being impaired. Further, by forming a color tone adjusting layer substantially free of both pigments and dyes, the adhesion between the carbonaceous substrate and the metal layer can be enhanced.

  The metal layer does not contain or contains a pigment. The metal layer does not contain or contains a dye. When the metal layer contains a pigment, the content of the pigment in 100% by weight of the metal layer is preferably 0.1% by weight or less, more preferably 0.01% by weight or less. When the metal layer contains a dye, the content of the dye in 100% by weight of the metal layer is preferably 0.1% by weight or less, more preferably 0.01% by weight or less.

  The metal oxide layer does not contain or contains a pigment. The metal oxide layer does not contain or contains a dye. When the metal oxide layer contains a pigment, the content of the pigment is preferably 0.1% by weight or less, more preferably 0.01% by weight or less in 100% by weight of the metal oxide layer. When the metal oxide layer contains a dye, the content of the dye in 100% by weight of the metal oxide layer is preferably 0.1% by weight or less, more preferably 0.01% by weight or less.

  In the color tone adjusting layer containing a pigment and the color tone adjusting layer containing a dye, the light transmittance is generally low, and the surface of the carbonaceous substrate is hardly visible. In the color tone adjusting layer containing a pigment and the color tone adjusting layer containing a dye, the light transmittance is generally low, and the surface pattern of the carbonaceous substrate is hardly visually recognized. Generally, the color tone adjusting layer containing a pigment and the color tone adjusting layer containing a dye are hardly provided with metallic luster.

The metal oxide layer contains a metal oxide. The metal oxide layer preferably comprises a metal oxide represented by MO _x, is preferably a metal oxide layer represented by MO _x. M in MO _x represents an n-valent metal, and x represents a number not less than n / 2.5 and not more than n / 2. Note that in the MO _x, O represents oxygen. One kind of the metal oxide may be used alone, or two or more kinds may be used in combination.

The metal layer contains a metal element. The metal layer may include, if a small amount of oxygen atoms, but in this case, the metal layer is a compound represented by MO _x, M in MO _x represents an n-valent metal, And x includes compounds having a value of more than 0 and less than n / 2.5 (preferably less than n / 20). A metal layer containing such a small amount of oxygen atoms is also called a metal layer. When the metal layer contains a metal alone, the metal layer contains a compound represented by M, and M represents a metal.

  The metal element contained in the metal layer may be used alone or in combination of two or more.

  When the metal oxide layer is not provided, or when a metal layer is provided instead of the metal oxide layer, the metal layer may be oxidized. When the metal contained in the metal layer is oxidized, the color of the metal layer may change, and the color tone of the metal sheet side of the laminated sheet may change.

  In the present invention, since the above-mentioned metal layer is provided, it is possible to impart a good metallic luster to the laminated sheet. Further, in the present invention, since the metal oxide layer is provided, discoloration due to oxidation of the metal in the metal layer can be suppressed, and as a result, change in color tone on the metal layer side of the laminated sheet can be suppressed. it can. Further, in the present invention, since the metal oxide layer is provided, the color tone of the laminated sheet can be adjusted. Further, in the present invention, since both the metal layer and the metal oxide layer are provided, it is possible to impart a good metallic gloss to the laminated sheet while maintaining the design of the surface of the carbonaceous substrate. And a change in color tone can be suppressed.

When M in MO _x represents an n-valent metal, and x represents a number greater than or equal to n / 2.5 and less than n / 2, MO _x is an incomplete oxide of the metal. Note that such an incomplete oxide of a metal is also referred to as a metal oxide. x is better the closer to n / 2.

  From the viewpoint of effectively suppressing a change in color tone on the metal layer side of the laminated sheet, x is preferably n / 2.5 or more, more preferably n / 2.2 or more, and further preferably n / 2.

When M in MO _x represents an n-valent metal and x represents a number of n / 2, MO _x is a complete oxide of the metal.

More preferably, M in MO _x represents an n-valent metal and x represents a number of n / 2. That is, it is more preferable that the metal oxide layer contains a complete metal oxide. In this case, since the metal contained in the metal oxide layer is not oxidized, discoloration of the color given to the laminated sheet can be suppressed. Further, even if the metal oxide layer is exposed to a high temperature or exposed to the air for a long time, discoloration of the applied color can be considerably suppressed.

For the valence of the oxygen atom, for example, the cross-section of the layer containing _{MO x, FE-TEM-EDX} ( e.g., manufactured by JEOL Ltd. "JEM-ARM200F") to elemental analysis, the area of the cross section of the layer containing the MO _x By calculating x from the element ratio of M and O per valence, the valence of the oxygen atom can be calculated.

Or suppressing the change in the metal layer side of the color tone of the laminated sheet more effectively, from the viewpoint or to better adjust the color tone of the laminated sheet, M in MO _x is silicon, zinc, silver, gold, titanium, Preferably, it is aluminum, tin, copper, iron, molybdenum, niobium, or indium. M in MO _x may include only one of these metal elements, or may include two or more of these metal elements. Or suppressing the change in the metal layer side of the color tone of the laminated sheet even more more effectively, from the viewpoint or to better adjust the color tone of the laminated sheet, M in MO _x is silicon, zinc, titanium, aluminum, tin , Niobium or indium, more preferably silicon or titanium.

Metal oxide contained in the metal oxide _{layer, TiO y, SiO y, ZnO} , Al 2 O y, Nb 2 O y, be the SnO _y, or _{an In} 2 _{O y} Preferably, TiO _y, or SiO More preferably, it is _y . Here, y is an arbitrary number that becomes a complete oxide of a metal or an incomplete oxide of a metal. The metal oxide contained in the metal oxide layer is preferably TiO ₂ , SiO ₂ , ZnO, Al ₂ O ₃ , Nb ₂ O ₅ , SnO ₂ , or In ₂ O ₃ , and TiO ₂ or SiO ₂ More preferably, it is ₂ . These metal oxides are complete oxides of the metal. The metal oxide layer may include only one type of these metal oxides, or may include two or more types of these metal oxides. When the metal oxide layer contains the above-described preferable metal oxide, the change in color tone can be more effectively suppressed, and the color tone of the laminated sheet can be adjusted favorably.

  The metal element contained in the metal oxide layer and the metal element contained in the metal layer may be the same or different. From the viewpoint of effectively making the color tone of the second surface of the laminated sheet different from the color tone of the surface of the carbonaceous substrate, the metal element contained most in the metal oxide layer and the metal element most contained in the metal layer It is preferable that the metal element be different from a metal element contained in a large amount.

  From the viewpoint of imparting a specific surface color and metallic luster to the laminated sheet, the metal element contained in the metal layer is preferably titanium, silver, aluminum, copper, chromium, or palladium, and titanium, silver, Or, it is more preferably aluminum. The metal layer may include only one of these metal elements, or may include two or more of these metal elements.

From the viewpoint of adjusting the color tone of the laminated sheet and giving the metallic glossiness better, it is preferable that the metal element most contained in the metal layer be silver or aluminum. When the metal element most contained in the metal layer is silver or aluminum, the second surface of the laminated sheet and the surface of the carbonaceous base material conform to JIS Z8781-4: 2013. The measured color difference ΔE ^* ab in the L ^* a ^* b ^* color system can be increased.

  From the viewpoint of better imparting metallic luster to the laminated sheet, the metal element most contained in the metal layer is preferably titanium.

From the viewpoint of further imparting a metallic luster to the laminated sheet even more favorably and further suppressing the change in color tone on the metal layer side of the laminated sheet even more effectively, the metal contained in the metal oxide layer most frequently is contained. Preferably, the oxide is TiO ₂ or SiO ₂ , and the metal element most contained in the metal layer is titanium, silver, or aluminum.

  The visible light transmittance of the metal oxide layer is preferably 5% or more, more preferably 8% or more, preferably 100% or less, more preferably 90% or less. When the visible light transmittance of the metal oxide layer is equal to or greater than the lower limit and equal to or less than the upper limit, the unevenness and glossiness of the carbonaceous substrate are not easily impaired, and the metal sheet has a good metallic gloss. Can be granted.

  The visible light transmittance is an average value of measured values obtained when the transmittance in the wavelength range of 380 nm to 780 nm is measured at 5 nm intervals. The visible light transmittance can be measured using, for example, a spectrophotometer (for example, “U-4100” manufactured by Hitachi High-Technologies Corporation). Note that an integrating sphere can be used as the detector.

  The visible light transmittance may be measured by preparing a metal oxide layer having the same average thickness as the metal oxide layer of the laminated sheet.

  Examples of the method for forming the metal oxide layer and the metal layer include sputtering (reactive sputtering method and RF sputtering method) and vapor deposition method (plasma vapor deposition method and the like, vacuum vapor deposition method (EB vapor deposition method, ion plating method). , IAD method)). From the viewpoint of further impairing the design properties such as unevenness and glossiness of the carbonaceous substrate, the metal oxide layer and the metal layer are preferably formed by sputtering, respectively, and a sputtering film It is preferred that In addition, when the metal oxide layer is a sputtered layer, the thickness of the metal oxide layer can be finely adjusted, so that the color tone of the laminated sheet can be adjusted precisely, and as a result, A desired color tone can be imparted to the laminated sheet.

  By changing the average thickness of the metal oxide layer and the metal layer, the visible light transmittance of the metal oxide layer and the metal layer is changed, and the color tone of the second surface of the laminated sheet is changed to various colors. Can be changed.

  The surface of the color tone adjusting layer opposite to the carbonaceous substrate is preferably not flat. The surface of the color adjustment layer opposite to the carbonaceous substrate is preferably uneven. The laminated sheet preferably has irregularities on the surface of the color tone adjustment layer opposite to the carbonaceous substrate side, the irregularities corresponding to the irregularities on the surface of the carbonaceous substrate on the color tone adjustment layer side. Such unevenness of the color tone adjusting layer can be favorably formed by sputtering or the like. On the other hand, when a paint containing a dye or a paint containing a pigment is applied on a carbonaceous substrate to form a color tone adjusting layer, the surface of the color tone adjusting layer is generally flat.

  The average thickness of the metal oxide layer is preferably 3 nm or more, more preferably 5 nm or more, and still more preferably 10 nm or more. The average thickness of the metal oxide layer is preferably 50 nm or less, more preferably 40 nm or less, further preferably less than 40 nm, particularly preferably 30 nm or less. When the average thickness of the metal oxide layer is not less than the lower limit, a change in color tone on the metal layer side of the laminated sheet can be effectively suppressed. When the average thickness of the metal oxide layer is equal to or less than the upper limit or less than the upper limit, the design properties of the carbonaceous substrate, such as unevenness and glossiness, are less likely to be impaired. When the average thickness of the metal oxide layer is equal to or less than the upper limit or less than the upper limit, the surface roughness, refraction resistance, and the like of the carbonaceous substrate are not easily impaired. Further, when the average thickness of the metal oxide layer is equal to or less than the upper limit or less than the upper limit, the color tone and texture of the metal derived from the metal layer can be maintained while maintaining the gloss and color tone of the metal layer.

  Note that, in general, when a layer containing a simple metal is exposed to the atmosphere or the like and the surface of the layer is naturally oxidized, the thickness of the formed metal oxide layer is less than 3 nm.

  The average thickness of the metal layer is preferably at least 10 nm, more preferably at least 20 nm, further preferably at least 30 nm, particularly preferably at least 40 nm, most preferably at least 50 nm. The average thickness of the metal layer is preferably 200 nm or less, more preferably 190 nm or less, further preferably 180 nm or less, particularly preferably 170 nm or less, and most preferably 150 nm or less. When the average thickness of the metal layer is equal to or more than the lower limit, the laminated sheet can be given a good metallic gloss. When the average thickness of the metal layer is equal to or less than the upper limit, the design properties of the carbonaceous substrate, such as unevenness and glossiness, are not easily impaired. When the average thickness of the metal layer is equal to or less than the upper limit, the surface roughness, refraction resistance and the like of the carbonaceous substrate are not easily impaired.

  The average thickness can be measured by, for example, observing a cross section of each of the metal oxide layer and the metal layer with an FE-TEM (for example, “JEM-ARM200F” manufactured by JEOL Ltd.). From the cross-sectional TEM image obtained by the FE-TEM, five or more arbitrary points separated by 100 nm or more from each point are selected, and the average value of the thickness measured at each point is defined as the average thickness.

From the viewpoint of imparting a good color to the laminated sheet, L ^* a ^{* of} the second surface of the laminated sheet and the surface of the carbonaceous substrate measured according to JIS Z8781-4: 2013 ^. The color difference ΔE ^* ab in the b ^* color system is preferably 10 or more, more preferably 15 or more, and further preferably 20 or more. The color difference ΔE ^* ab between the second surface of the laminated sheet and the surface of the carbonaceous substrate may be 50 or less.

From the viewpoint of imparting a good color to the laminated sheet, in the measurement of the lightness L ^* in the L ^* a ^* b ^* color system measured according to JIS Z8781-4: 2013, the second of the laminated sheet is measured. The lightness L ^* of the surface is preferably higher than the lightness L ^* of the carbonaceous substrate by 5 or more, more preferably 6 or more, and even more preferably 7 or more. A lightness L ^* of the second surface of the laminated sheet, lightness L ^* and the surface of the carbonaceous substrate may be different in 50 or less.

When measuring the color difference ΔE ^* ab and the lightness L ^* of the surface of the carbonaceous substrate, the carbonaceous substrate before the color tone adjustment layer is disposed may be used. When the surfaces on both sides of the carbonaceous substrate are the same, the measurement may be performed on the surface on the opposite side of the color adjustment layer side of the carbonaceous substrate.

From the viewpoint of effectively suppressing a change in color tone on the metal layer side of the laminated sheet, the second surface of the laminated sheet and the laminated sheet are allowed to stand at a temperature of 85 ° C. and a humidity of 85% RH for 240 hours. The color difference ΔE ^* ab in the L ^* a ^* b ^* color system measured with the second surface of the laminated sheet according to JIS Z8781-4: 2013 is preferably 10 or less, more preferably It is 5 or less, more preferably 3 or less.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to the following examples.

(Example 1)
Formation of the second color tone adjusting layer (metal layer):
As the carbonaceous base material, a carbon fiber base material ("TR3523 M" manufactured by Mitsubishi Chemical Corporation, thickness 0.21 mm), which is a woven fabric in which carbon fibers (basis weight 200 g / m ² , filament diameter 7 μm) are woven by twill weave, is used. Using. The carbonaceous substrate was placed in a vacuum device and evacuated to a pressure of 5.0 × 10 ⁻⁴ Pa or less. Subsequently, an argon gas was introduced, and a Ti layer (average thickness: 50 nm) was formed as a second color tone adjusting layer on the surface of the carbonaceous substrate by DC magnetron sputtering, so that the carbonaceous substrate was A laminate with the color tone adjusting layer of No. 2 was obtained.

Formation of first color tone adjusting layer (metal oxide layer):
The laminated body of the carbonaceous substrate and the second color tone adjusting layer was placed in a vacuum device, and evacuated to a pressure of 5.0 × 10 ⁻⁴ Pa or less. Subsequently, an argon gas and an oxygen gas are introduced, and a TiO ₂ layer as a first color tone adjustment layer is formed on the surface of the second color tone adjustment layer opposite to the carbonaceous substrate by DC magnetron sputtering. (Average thickness: 1 nm) to obtain a laminated sheet.

(Examples 2 to 6)
A laminated sheet was obtained in the same manner as in Example 1, except that the average thickness of the first color tone adjusting layer was changed as shown in Table 1.

(Examples 7 to 10)
A laminated sheet was obtained in the same manner as in Example 1, except that the average thickness of the first color tone adjustment layer and the material of the second color tone adjustment layer were changed as shown in Tables 1 and 2.

(Examples 11 to 14)
A laminated sheet was obtained in the same manner as in Example 1, except that the material and the average thickness of the first color tone adjusting layer were changed as shown in Table 2.

(Example 15)
A laminated sheet was obtained in the same manner as in Example 1, except that the average thickness of the first color tone adjusting layer was changed as shown in Table 2.

(Examples 16 and 17)
A laminated sheet was obtained in the same manner as in Example 1, except that the average thickness of the first color tone adjustment layer and the material of the second color tone adjustment layer were changed as shown in Table 2.

(Comparative Example 1)
The carbon fiber base material (“TR3523M”, manufactured by Mitsubishi Chemical Corporation, thickness: 0.21 mm) in Example 1 was evaluated in Comparative Example 1. In Comparative Example 1, both the first color tone adjustment layer and the second color tone adjustment layer were not formed.

(Comparative Example 2)
In the same manner as in Example 1, a Ti layer (average thickness: 50 nm) was formed as a second color tone adjusting layer to obtain a laminated sheet. In Comparative Example 2, the first color tone adjusting layer was not formed.

(Comparative Example 3)
The carbon fiber base material in Example 1 was prepared. A coating containing a blue pigment is applied to one surface of the carbon fiber base material to form a colored layer (a color adjustment layer having no light transmission, average thickness of 15 μm), and a colored layer is formed on the second surface side. Was obtained.

(Comparative Example 4)
An Ag layer (average thickness 50 nm) was formed as a second color tone adjusting layer in the same manner as in Example 1 to obtain a laminated sheet. In Comparative Example 4, the first color tone adjusting layer was not formed.

(Comparative Example 5)
In the same manner as in Example 1, an Al layer (average thickness: 50 nm) was formed as a second color tone adjusting layer to obtain a laminated sheet. In Comparative Example 5, the first color tone adjusting layer was not formed.

(Evaluation)
(1) Uneven shape (surface pattern)
When the second surface of the obtained laminated sheet was observed, it was visually confirmed whether or not the unevenness (surface pattern) of the carbon fiber substrate used for the carbonaceous substrate was damaged. In Comparative Example 1, since neither the first color tone adjustment layer nor the second color tone adjustment layer was formed, the unevenness (surface pattern) was not evaluated.

[Judgment criteria for uneven shape (surface pattern)]
：: The uneven shape is not damaged ×: The uneven shape is damaged

(2) Metallic gloss When the second surface of the obtained laminated sheet and the surface of the carbonaceous substrate (Comparative Example 1) were observed, it was visually confirmed whether or not it had metallic gloss.

  In addition, the surface of the carbonaceous substrate of Comparative Example 1 corresponds to the surface of the carbonaceous substrate (first surface of the laminated sheet) in the laminated sheets obtained in Examples 1 to 17 and Comparative Examples 2 to 5. .

[Criteria for metallic glossiness]
：: Has metallic luster ×: Does not have metallic luster

(3) Color difference Using a spectrophotometer (“U-4100” manufactured by Hitachi High-Tech Co., Ltd.), in accordance with JIS Z8781-4: 2013, the laminated sheet (Examples 1 to 17 and Comparative Examples 2 to 5) L ^* , a ^* , and b ^* in the L ^* a ^* b ^* color system of the surface of No. 2 and the surface of the carbonaceous substrate (Comparative Example 1) were determined.

  In addition, the surface of the carbonaceous substrate of Comparative Example 1 corresponds to the surface of the carbonaceous substrate (first surface of the laminated sheet) in the laminated sheets obtained in Examples 1 to 17 and Comparative Examples 2 to 5. .

From L ^* , a ^* , and b ^* , the color difference in the L ^* a ^* b ^* color system between the second surface of the laminated sheet and the surface of the fiber base material of the laminated sheet according to JIS Z8781-4: 2013. ΔE ^* ab was determined.

(4) Color difference (after endurance test)
The obtained laminated sheet was allowed to stand in a thermo-hygrostat (temperature: 85 ° C., humidity: 85% RH) for 240 hours. After standing, L ^* a ^* b ^* of the second surface of the obtained laminated sheet was measured using a spectrophotometer (“U-4100” manufactured by Hitachi High-Technologies Corporation) in accordance with JIS Z8781-4: 2013 ^. L ^* , a ^* , and b ^* in the color system were determined.

From the L ^* , a ^* , and b ^* , the second surface of the laminated sheet obtained in (3) above and the second surface of the laminated sheet after standing in accordance with JIS Z8781-4: 2013. The color difference ΔE ^* ab in the L ^* a ^* b ^* color system was determined. In Comparative Example 1, the color difference (after the durability test) was not evaluated because neither the first color tone adjustment layer nor the second color tone adjustment layer was formed.

[Criteria for color difference (after endurance test)]
○: Color difference ΔE ^* ab is 3 or less ○: Color difference ΔE ^* ab exceeds 3 and 5 or less Δ: Color difference ΔE ^* ab exceeds 5 and 10 or less ×: Color difference ΔE ^* ab exceeds 10

(5) Color Difference of Second Surface of Laminated Sheet Due to Presence or Absence of Metal Oxide Layer In the laminated sheet obtained in the example, a metal oxide layer (first color adjustment layer) and a metal layer (second 2 color tone adjusting layers). In the laminated sheets obtained in Comparative Examples 2, 4, and 5, only the metal layer (second color adjustment layer) was disposed as the color adjustment layer, and the metal oxide layer (first color adjustment layer) was disposed. Not. In the combination of the laminated sheet obtained in the example in which the material and the average thickness of the second color tone adjusting layer (metal layer) are the same and the laminated sheet obtained in the comparative example, the second surface of each laminated sheet The color difference ΔE * ab in the L ^* a ^* b ^* color system was determined from L ^* , a ^* , and b ^{* of the above according} to JIS Z8781-4: 2013. Specifically, in the following combinations of the laminated sheets, the color difference ΔE ^* ab on the second surface of the laminated sheet was determined.

(I) The second surface of the laminated sheet obtained from Examples 1 to 6, 11 to 15 (metal layer: Ti layer, metal oxide layer: TiO ₂ layer or SiO ₂ layer) and Comparative Example 2 (metal (Ii) Lamination obtained in Examples 7, 8, and 16 (metal layer: Ag layer, metal oxide layer: TiO ₂ layer) Color difference between the second surface of the sheet and the second surface of the laminated sheet obtained in Comparative Example 4 (metal layer: Ag layer) (iii) Examples 9, 10, 17 (metal layer: Al layer, metal) Color difference between the second surface of the laminated sheet obtained with the oxide layer: TiO ₂ layer) and the second surface of the laminated sheet obtained with the comparative example 5 (metal layer: Al layer)

[Criteria for judging color difference of second surface of laminated sheet based on presence / absence of metal oxide layer]
A: Color difference ΔE ^* ab is 3 or less B: Color difference ΔE ^* ab exceeds 3 and 10 or less C: Color difference ΔE ^* ab exceeds 10 and 20 or less D: Color difference ΔE ^* ab exceeds 20

  The structures and results of the laminated sheet are shown in Tables 1 to 3 below.

DESCRIPTION OF SYMBOLS 1 ... Laminated sheet 1a ... 1st surface 1b ... 2nd surface 2 ... Carbonaceous base material 3 ... Color tone adjustment layer 31 ... Metal oxide layer (1st color tone adjustment layer)
32: Metal layer (second color tone adjusting layer)

Claims (6)

A carbonaceous substrate, a metal layer disposed on the surface of the carbonaceous substrate, and a metal oxide layer disposed on a surface of the metal layer opposite to the carbonaceous substrate. Prepared,
The carbonaceous substrate is a carbon fiber substrate,
A laminated sheet having an average thickness of the metal oxide layer of less than 40 nm (excluding a laminated sheet provided with an adhesive material between the carbonaceous substrate and the metal layer) .   The laminated sheet according to claim 1, wherein the metal element contained in the metal layer is titanium, silver, or aluminum.   3. The laminated sheet according to claim 1, wherein the metal oxide layer has an average thickness of 3 nm or more. 4.   The laminated sheet according to any one of claims 1 to 3, wherein the metal oxide layer has an average thickness of 30 nm or less. The metal oxide contained in the metal oxide layer, TiO _2, or SiO _2, the laminated sheet according to any one of claims 1 to 4. The laminated sheet according to any one of claims 1 to 5, which is used as a decorative base sheet.

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