TW202112550A - Electromagnetic wave transmissive layered product - Google Patents

Abstract

The present invention relates to an electromagnetic wave transmissive layered product provided with: a substrate; a metallic luster layer formed on the substrate; and a resin layer, wherein reflectivity Y of reflected light in the wavelength range of 380-780 nm according to SCE measurement in a CIE-XYZ colorimetric system is 1-60%.

Description

Electromagnetic wave permeable laminate

The present invention relates to a laminated body with electromagnetic wave permeability.

Previously, a member with electromagnetic wave permeability and metallic luster has both high-level sense derived from its metallic luster appearance and electromagnetic wave permeability, so it is preferably used in a device for transmitting and receiving electromagnetic waves. In the case of metallic luster color components using metal, the transmission and reception of electromagnetic waves is substantially impossible or interfered. Therefore, in order not to interfere with the transmission and reception of electromagnetic waves and not to damage the design, there is a need for an electromagnetic wave permeable laminate that has both metallic luster and electromagnetic wave permeability.

It is expected that the electromagnetic wave-permeable laminate will be used in various devices that require communication as a device for transmitting and receiving electromagnetic waves, such as door handles of automobiles equipped with smart keys, in-vehicle communication devices, mobile phones, computers and other electronic devices. Furthermore, in recent years, with the development of IoT technology, it is also expected to be applied to a wide range of fields, such as refrigerators and other household appliances, and life equipment that have not previously been communicated. In addition, from the viewpoint of design, these electromagnetic wave-permeable laminates sometimes require a texture with metallic luster and a dark tone with suppressed brightness.

Regarding the electromagnetic wave permeable laminate, Patent Document 1 discloses a resin product containing a metal coating made of chromium (Cr) or indium (In). The resin product includes: a resin substrate, an inorganic base film containing an inorganic compound formed on the resin base film, and a bright discontinuous structure formed on the inorganic base film by a physical vapor deposition method Metal film made of chromium (Cr) or indium (In). On the other hand, as an electromagnetic wave transmissive laminate that does not have electromagnetic wave permeability, Patent Document 2 discloses a light reflection laminate that is composed of a light reflector including a metal layer or a white reflective film and a light diffusion layer. The laminated body for light reflection has high reflectance and diffusivity in light reflection for low-angle incident light, and has excellent reflection efficiency. Prior art literature Patent literature

Patent Document 1: Japanese Patent Laid-Open No. 2007-144988 Patent Document 2: International Publication No. 2009/139402

[The problem to be solved by the invention]

However, it is difficult to control the brightness of the metal film in the prior art, and it is difficult to provide a laminate that exhibits excellent electromagnetic wave permeability, has metallic luster, and has an excellent metallic appearance with suppressed brightness. The present invention was completed to solve the problems in the prior art, and the object is to provide an electromagnetic wave permeable laminate with excellent electromagnetic wave permeability, metallic luster and suppressed glossiness and excellent metallic appearance. [Technical means to solve the problem]

The inventors of the present invention conducted intensive research to solve the above-mentioned problems, and found that the reflection of reflected light in the range of 380 nm to 780 nm in the wavelength range of 380 nm to 780 nm was reflected in the SCE measurement of the CIE-XYZ color system by providing a metallic luster layer. The rate Y is 1 to 60%, and an electromagnetic wave permeable laminate having excellent electromagnetic wave permeability, metallic luster, and suppressed brightness can be obtained, thereby completing the present invention.

[1] An electromagnetic wave-permeable laminated body comprising a substrate, a metallic luster layer formed on the above-mentioned substrate, and a resin layer, and the reflected light in the wavelength range of 380 nm to 780 nm is reflected in the SCE of the CIE-XYZ color system The reflectance Y in the measurement is 1-60%. [2] The electromagnetic wave permeable laminate as described in [1], wherein the metallic luster layer is a metal layer, and the metal layer includes at least a plurality of portions in a discontinuous state. [3] The electromagnetic wave permeable laminate as described in [2], wherein the metal layer is a layer containing aluminum or an aluminum alloy. [4] The electromagnetic wave permeable laminate according to any one of [1] to [3], wherein the resin layer includes a layer containing light diffusing fine particles. [5] The electromagnetic wave transmissive laminate according to any one of [1] to [4], wherein the resin layer includes a light-diffusing adhesive layer. [6] The electromagnetic wave permeable laminate according to any one of [1] to [5], wherein an indium oxide-containing layer is further provided between the substrate and the metallic luster layer. [7] The electromagnetic wave permeable laminate as described in [6], wherein the indium oxide-containing layer is provided in a continuous state. [8] The electromagnetic wave permeable laminate as described in [6] or [7], wherein the indium oxide-containing layer includes one of indium oxide (In ₂ O ₃ ), indium tin oxide (ITO), or indium zinc oxide (IZO) Either. [9] The electromagnetic wave permeable laminate according to any one of [6] to [8], wherein the thickness of the indium oxide-containing layer is 1 nm to 1000 nm. [10] The electromagnetic wave permeable laminate according to any one of [6] to [9], wherein the thickness of the metallic luster layer is 5 nm to 100 nm. [11] The electromagnetic wave permeable laminate according to any one of [6] to [10], wherein the ratio of the thickness of the metallic luster layer to the thickness of the indium oxide-containing layer (thickness of the metallic luster layer/the thickness of the indium oxide-containing layer) The thickness of the indium oxide layer is 0.02-100. [12] The electromagnetic wave permeable laminate described in any one of [1] to [11] has a sheet resistance of 100 Ω/□ or more. [13] The electromagnetic wave permeable laminate as described in [2], wherein the plurality of parts are formed in an island shape. [14] The electromagnetic wave permeable laminate as described in any one of [1] to [13], wherein any of the above-mentioned base system substrate film, resin molding substrate, glass substrate, or articles that should be given metallic luster One. [Effects of Invention]

According to the present invention, it is possible to provide an electromagnetic wave permeable laminate having excellent electromagnetic wave permeability, a metallic luster, and an excellent metallic appearance with suppressed brilliance.

Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. In the following content, for the convenience of description, only the preferred embodiments of the present invention are shown, but of course, the present invention is not intended to be limited thereby.

＜1. Basic structure＞ The electromagnetic wave transmissive laminate of the embodiment of the present invention includes a substrate, a metallic luster layer formed on the substrate, and a resin layer, and the reflected light in the wavelength range of 380 nm to 780 nm is reflected in the SCE of the CIE-XYZ color system The reflectance Y in the measurement is 1 to 60%. The metallic luster layer is preferably a metal layer, and the metal layer includes at least a plurality of parts in a discontinuous state. Hereinafter, the case of the metallic luster layer-based metal layer may be described, but the present invention is not limited by the following description. 1 to 4 show schematic cross-sectional views of the electromagnetic wave transmissive laminate 1 according to one embodiment of the present invention. In addition, in FIG. 5, in order to illustrate the discontinuous structure of the metal layer, an electron micrograph (SEM image) of the surface of the metal layer of the electromagnetic wave permeable laminate is shown. In addition, FIG. 7 shows a transmission electron micrograph (TEM image) of a cross-sectional view of the metal layer 12 with an island structure in one embodiment of the present invention.

As shown in FIG. 1, the electromagnetic wave permeable laminate 1 includes a base 10, a metallic luster layer (metal layer 12) formed on the base 10, and a resin layer 13.

The metal layer 12 is formed on the base 10. The metal layer 12 includes a plurality of parts 12a. At least a part of the plurality of portions 12a in the metal layer 12 is in a discontinuous state, in other words, at least a part is separated by a gap 12b. Since they are separated by the gap 12b, the sheet resistance of the plurality of parts 12a increases, and the interaction with the electric wave decreases, so that the electric wave can be transmitted. The respective parts 12a may also be an aggregate of sputtered particles formed by vapor deposition, sputtering of metal, or the like.

Furthermore, the "discontinuous state" in this specification means a state of being separated from each other by the gap 12b, and the result is a state of being electrically insulated from each other. Due to the electrical insulation, the sheet resistance becomes larger and the required electromagnetic wave permeability can be obtained. That is, with the metal layer 12 formed in a discontinuous state, it is easy to obtain sufficient brightness, and electromagnetic wave permeability can also be ensured. The shape of the discontinuity is not particularly limited, and includes, for example, an island structure, a cracked structure, and the like. Here, the so-called "island-like structure" refers to a structure in which metal particles are independent of each other, and the particles are slightly separated from each other or in a state of being partially in contact with each other.

The so-called cracked structure refers to the structure in which the metal film is broken due to cracks. The metal layer 12 of the cracked structure can be formed by, for example, disposing a metal thin film layer on the base film and bending and extending the metal thin film layer to cause cracks in the metal thin film layer. At this time, by providing a brittle layer made of a material that lacks stretchability, that is, easily cracked by stretching, between the base film and the metal thin film layer, the metal layer 12 with a cracked structure can be easily formed.

As described above, the discontinuous aspect of the metal layer 12 is not particularly limited, but from the viewpoint of productivity, it is preferably an island structure.

Regarding the electromagnetic wave transmissive laminate 1 of this embodiment, the reflectance Y of the reflected light in the wavelength range of 380 nm to 780 nm in the SCE (Regular Reflected Light Removal) measurement of the CIE-XYZ color system is 1 to 60 %. By setting the reflectance Y in this range, it is possible to obtain an electromagnetic wave-transmitting laminate having a metallic luster and having an excellent metallic appearance with suppressed brilliance. The reflectance Y represents the visual reflectance, and when the reflectance Y is 1% or more, the brightness can be suppressed. The reflectance Y is more preferably 10% or more, and still more preferably 20% or more. The reflectance Y uses D65 as a standard light source, and can be measured by measuring equipment such as a spectrophotometer CM-2600d manufactured by Konica Minolta Co., Ltd., and can be measured by the method described in the examples.

The electromagnetic wave permeability of the electromagnetic wave permeable laminate 1 can be evaluated, for example, by the amount of attenuation of radio wave transmission. Furthermore, there is a correlation between the radio wave transmission attenuation in the microwave frequency band (5 GHz) and the radio wave transmission attenuation in the millimeter wave radar frequency band (76～80 GHz). Since the display is relatively close, the microwave frequency band The electromagnetic wave permeability laminated body with excellent electromagnetic wave permeability also has excellent electromagnetic wave permeability in the frequency band of millimeter wave radar. The radio wave transmission attenuation in the microwave band (5 GHz) is preferably 10 [-dB] or less, more preferably 5 [-dB] or less, and still more preferably 2 [-dB] or less. If it is greater than 10[-dB], there is a problem that more than 90% of the radio waves are blocked.

The sheet resistance of the electromagnetic wave permeable laminate 1 is also related to the electromagnetic wave permeability. The sheet resistance of the electromagnetic wave transmissive laminate 1 is preferably 100 Ω/□ or more. In this case, the attenuation of the radio wave transmission in the microwave frequency band (5 GHz) is about 10 to 0.01 [-dB]. The sheet resistance of the electromagnetic wave permeable laminate 1 is more preferably 200 Ω/□ or more, still more preferably 600 Ω/□ or more, and particularly preferably 1000 Ω/□ or more. The sheet resistance of the electromagnetic wave permeable laminate 1 can be measured by the eddy current measurement method in accordance with JIS-Z2316-1:2014.

The radio wave transmission attenuation and sheet resistance of the electromagnetic wave permeable laminate 1 are affected by the material or thickness of the metallic luster layer. In addition, when the electromagnetic wave permeable laminate 1 is provided with the indium oxide-containing layer 11, it is also affected by the material and thickness of the indium oxide-containing layer 11.

＜2. Matrix＞ As the base 10, from the viewpoint of electromagnetic wave permeability, resin, glass, ceramics, and the like can be cited. The base 10 may also be any one of a base film, a resin molded product base, a glass base, or an article that should be imparted with metallic luster. More specifically, as the base film, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, polyamide, Polyvinyl chloride, polycarbonate (PC), cyclic olefin polymer (COP), polystyrene, polypropylene (PP), polyethylene, polycyclic olefin, polyurethane, acrylic resin (PMMA), Transparent films of homopolymers or copolymers such as ABS (acrylonitrile-butadiene-styrene, acrylonitrile-butadiene-styrene).

According to these components, there is no influence on the brightness or electromagnetic wave permeability. Among them, from the viewpoint of forming the indium oxide-containing layer 11 or the metallic luster layer later, it is preferably one that can withstand high temperatures such as evaporation or sputtering. Therefore, among the above-mentioned materials, for example, polyterephthalene is preferable. Ethylene formate, polyethylene naphthalate, acrylic resin, polycarbonate, cycloolefin polymer, ABS, polypropylene, polyurethane. Among them, in terms of a good balance between heat resistance and cost, polyethylene terephthalate, cycloolefin polymer, polycarbonate, and acrylic resin are preferred.

The base film may be a single-layer film or a multilayer film. In terms of ease of processing and the like, the thickness is preferably about 6 μm to 250 μm, for example. In order to enhance the adhesion of the indium oxide-containing layer 11 or the metallic luster layer, plasma treatment or easy bonding treatment can also be implemented. Moreover, it is preferable that it does not contain particles. When the base 10 is a base film, the metallic luster layer may be provided on at least a part of the base film, and it may be provided only on one side of the base film or on both sides.

Here, it should be noted that the base film is only an example of an object (base 10) that can form a metallic luster layer on its surface. In addition to the above-mentioned base film, the base 10 also includes a resin molded article base material, a glass base material, and the article itself to be imparted with metallic luster. Examples of substrates for resin moldings and articles that should be given metallic luster include: structural parts for vehicles, vehicle-mounted products, housings for electronic equipment, housings for household appliances, structural parts, mechanical parts, various automotive parts Parts, parts for electronic equipment, parts for household products such as furniture and kitchenware, parts for medical equipment, construction materials, other structural parts or exterior parts, etc.

The metallic luster layer can be formed on all the substrates, can be formed on a part of the surface of the substrate, or can be formed on the entire surface of the substrate. In this case, the base 10 to which the metallic luster layer should be provided preferably satisfies the same material and conditions as the above-mentioned base film.

＜3. Indium oxide containing layer＞ Moreover, as shown in FIG. 2, the electromagnetic wave permeable laminate 1 of one embodiment may further include an indium oxide-containing layer 11 between the base 10 and the metallic luster layer (metal layer 12). The indium oxide-containing layer 11 may be directly provided on the surface of the base 10 or indirectly through a protective film or the like provided on the surface of the base 10. The indium oxide-containing layer 11 is preferably provided in a continuous state on the surface of the substrate 10 to be provided with metallic luster, in other words, it is provided without gaps. By being arranged in a continuous state, the smoothness or corrosion resistance of the indium oxide-containing layer 11, the metal layer 12, or the electromagnetic wave-permeable laminate 1 can be improved, and it is also easy to form the indium oxide-containing layer 11 uniformly in the surface. .

In this way, an indium oxide-containing layer 11 is further provided between the base 10 and the metal layer 12, that is, an indium oxide-containing layer 11 is formed on the base 10 and a metal layer 12 is formed thereon, thereby facilitating formation in a discontinuous state The metal layer 12 is therefore preferred. The details of the mechanism are not necessarily clear, but it is believed that when metal vapor deposition or sputtered particles form a film on the substrate, the surface diffusibility of the particles on the substrate will affect the shape of the film. When the temperature of the substrate is high, the metal When the wettability of the layer to the substrate is low and the melting point of the material of the metal layer is low, it is easy to form a discontinuous structure. In addition, it is believed that by providing the indium oxide-containing layer on the substrate, the surface diffusibility of the metal particles on the surface is promoted, and the metal layer is easily grown in a discontinuous state.

_{Indium oxide (In 2} O ₃ ) itself can be used to form the indium oxide-containing layer 11, or a metal-containing substance such as indium tin oxide (ITO) or indium zinc oxide (IZO) can be used to form the indium oxide-containing layer 11. Among them, ITO or IZO containing the second metal has high discharge stability during the sputtering step, so it is better. By using these indium oxide-containing layers 11, it is also possible to form a continuous film along the surface of the substrate. In this case, it is easy to form the metal layer laminated on the indium oxide-containing layer into, for example, an island shape. Continuous structure is preferred. Furthermore, as described below, in this case, in addition to chromium (Cr) or indium (In), the metal layer easily contains various metals such as aluminum, and these metals are generally difficult to form a discontinuous structure and are difficult to apply to this application.

The mass ratio of tin oxide (SnО ₂ ) contained in ITO, that is, the content rate (content ratio=(SnO ₂ /(In ₂ O ₃ +SnO ₂ ))×100) is not particularly limited, for example 2.5% by mass to 30% by mass , More preferably 3% by mass to 10% by mass. In addition, the mass ratio of zinc oxide (ZnO) contained in IZO, that is, the content ratio (content ratio=(ZnO/(In ₂ O ₃ +ZnO))×100) is, for example, 2% by mass to 20% by mass. The thickness of the indium oxide-containing layer 11 is generally preferably 1000 nm or less, more preferably 50 nm or less, and still more preferably 20 nm or less from the viewpoint of sheet resistance, electromagnetic wave permeability, and productivity. On the other hand, in order to easily make the laminated metal layer 12 in a discontinuous state, it is preferably 1 nm or more, and to ensure that the laminated metal layer 12 is in a discontinuous state, it is more preferably 2 nm or more, and more preferably Above 5 nm.

＜4. Metallic luster layer＞ The metallic luster layer is formed on the base 10. The metallic luster layer is a layer with a metallic appearance, preferably a layer with metallic luster. The material for forming the metallic luster layer is not particularly limited, and may contain metal or resin, or may contain metal and resin. In the case where the metallic luster layer is formed only of resin, by laminating resins with different refractive indexes, a metallic luster can also be obtained. In order to exert sufficient metallic luster, the thickness of the metallic luster layer is generally preferably 5 nm or more. On the other hand, from the viewpoint of sheet resistance or electromagnetic wave permeability, it is generally preferably 100 nm or less. For example, it is more preferably 7 nm to 100 nm, and still more preferably 10 nm to 70 nm. The thickness is also suitable for forming a uniform film with good productivity, and the appearance of the resin molded product as the final product is also good. The metallic luster layer is preferably a metal layer, and the metal layer preferably includes at least a plurality of portions in a discontinuous state.

(Metal layer) The metal layer 12 is formed on the substrate, and includes at least a plurality of parts in a discontinuous state. In the case where the metal layer 12 is in a continuous state on the substrate, although sufficient metallic luster can be obtained, the transmission attenuation of radio waves becomes very large, and therefore, the transmission of electromagnetic waves cannot be ensured.

The details of the mechanism of the discontinuous state of the metal layer 12 on the substrate are not necessarily clear, but can be roughly estimated as follows. That is, in the film formation process of the metal layer 12, the ease of forming a discontinuous structure is related to the surface diffusion of the metal layer 12 on the substrate to which the metal layer 12 is provided. The substrate temperature is high, and the wettability of the metal layer to the substrate is small. The low melting point of the material of the metal layer tends to form a discontinuous structure. Therefore, it is believed that metals with relatively low melting points such as zinc (Zn), lead (Pb), copper (Cu), and silver (Ag) can also be used for metals other than aluminum (Al) specifically used in the following examples. The method forms a discontinuous structure.

It is desirable that the metal layer 12 can of course exhibit sufficient brightness and has a relatively low melting point. The reason is that the metal layer 12 is preferably formed by thin film growth using sputtering. For this reason, as the metal layer 12, a metal having a melting point of about 1000° C. or less is suitable, for example, it is preferable to include a metal selected from aluminum (Al), zinc (Zn), lead (Pb), copper (Cu), and silver ( Any one of at least one metal in Ag) and an alloy containing the metal as a main component. In particular, for reasons such as the brightness or stability of the substance, and the price, it is preferable to include Al or its alloys, and more preferably Al and its alloys. In addition, when an aluminum alloy is used, the aluminum content is preferably 50% by mass or more.

The equivalent diameter of the circle of the portion 12a of the metal layer 12 is not particularly limited, and is usually about 10 to 1000 nm. The average particle diameter of the plural parts 12a means the average value of the circle-equivalent diameters of the plural parts 12a. The circle equivalent diameter of the part 12a refers to the diameter of a true circle equivalent to the area of the part 12a. Moreover, the distance between each part 12a is not specifically limited, Usually, it is about 10-1000 nm.

In order to exhibit sufficient metallic luster, the thickness of the metal layer 12 is generally preferably 5 nm or more. On the other hand, from the viewpoint of sheet resistance or electromagnetic wave permeability, it is generally preferably 100 nm or less. For example, it is preferably 10 nm to 100 nm, more preferably 15 nm to 70 nm. The thickness is also suitable for forming a uniform film with good productivity, and the appearance of the resin molded product as the final product is also good.

In addition, for the same reason, the ratio of the thickness of the metallic luster layer to the thickness of the indium oxide-containing layer (thickness of the metallic luster layer/thickness of the indium oxide-containing layer) is preferably in the range of 0.02-100, more preferably 0.1-100 The range is more preferably 0.3-35.

The sheet resistance of the metallic luster layer is preferably 100 Ω/□ or more. In this case, the electromagnetic wave transmittance is about 10 to 0.01 [-dB] at a wavelength of 5 GHz. More preferably, it is 1000 Ω/□ or more.

When the indium oxide-containing layer is further provided, the sheet resistance as a laminate of the metallic luster layer and the indium oxide-containing layer is preferably 100 Ω/□ or more. In this case, the electromagnetic wave transmittance is about 10 to 0.01 [-dB] at a wavelength of 5 GHz. More preferably, it is 1000 Ω/□ or more. Needless to say, the value of the sheet resistance is affected by the material or thickness of the metallic luster layer, and is also affected to a greater extent by the material or thickness of the indium oxide-containing layer as the base layer. Therefore, when setting the indium oxide-containing layer, it is necessary to set it on the basis of considering the relationship with the indium oxide-containing layer.

<5. Barrier layer> As shown in FIG. 4, the electromagnetic wave transmissive laminated body 1 may be equipped with the barrier layer 14 on the surface of the metallic luster layer (metal layer 12) on the side opposite to the base 10 side. Furthermore, the barrier layer 14 may be laminated on the metal layer 12, and it is not necessary to completely fill the gap 12b. The barrier layer 14 is a layer for inhibiting the oxidation (corrosion) of the metal layer 12. The barrier layer preferably includes at least one selected from the group consisting of at least one oxide, nitride, carbide, oxynitride, oxycarbide, nitride carbide, and oxynitride carbide selected from the group consisting of metals and semimetals. 1 kind. As the metal, for example, aluminum, titanium, indium, magnesium, etc. can be used, and as the semimetal, for example, silicon, bismuth, germanium, etc. can be used. Specifically, for example, ZnO + Al ₂ O ₃ (AZO), indium zinc oxide (IZO), indium tin oxide (ITO), silicon oxide carbide nitride film (SiOCN), silicon oxide nitride film (SiON), nitride Silicon film (SiN), SiO _X , AlO _X , AlON, TiO _X etc. In order to improve the barrier layer 14's ability to inhibit the oxidation (corrosion) of the metal layer 12 (hereinafter also referred to as "barrier properties"), it is preferable to include carbon and nitrogen for densifying the network structure (network structure) in the barrier layer. In order to further improve transparency, it is preferable to contain oxygen. That is, the barrier layer is preferably an oxynitride carbide containing at least one of metal and semimetal.

In addition, in order to improve barrier properties, the barrier layer is preferably not easily permeable to water vapor. The water vapor transmission degree of the barrier layer can be evaluated by various methods, for example, the water vapor transmission degree measured by the method described in the column of Examples can be used for evaluation. In order to improve barrier properties, the water vapor transmission rate is preferably 3 g/m ² /day or less, more preferably 1 g/m ² /day or less, and still more preferably 0.5 g/m ² /day or less.

The thickness of the barrier layer 14 is not particularly limited. In order to improve the barrier properties, it is preferably 5 nm or more, more preferably 10 nm or more, and still more preferably 20 nm or more. In addition, in order to improve the electromagnetic wave permeability or the metallic luster of the appearance, it is preferably 100 nm or less, more preferably 70 nm or less, and still more preferably 50 nm or less.

In addition, in order to further inhibit the oxidation (corrosion) of the metal layer 12, the barrier layer may be further disposed between the metal layer and the substrate. When the electromagnetic wave permeable laminate 1 is provided with an indium oxide-containing layer, a barrier layer may be provided between the indium oxide-containing layer and the metal layer, or a barrier layer may be provided on the side of the indium oxide-containing layer opposite to the metal layer. Moreover, it can also be installed in these two places.

In addition to the above-mentioned metal layer, indium oxide-containing layer, and barrier layer, the electromagnetic wave permeable laminate may be provided with other layers depending on the application. Examples of other layers include: an optical adjustment layer (color adjustment layer) of high-refractive materials to adjust appearance such as color tone, a protective layer (scratch resistance layer) to improve durability such as abrasion resistance, and easy adhesion Layer, hard coating, anti-reflective layer, light emitting layer, and anti-glare layer, etc.

＜6. Resin layer＞ The electromagnetic wave transmissive laminate of the present embodiment includes a resin layer 13. As shown in FIG. 1, the resin layer 13 is preferably formed on the metallic luster layer. The resin layer 13 may also be an optical adjustment layer (color adjustment layer) of high-refractive materials used to adjust appearance such as color tone, etc., a protective layer (scratch resistance layer) used to improve durability such as moisture resistance or abrasion resistance, Easy bonding layer, adhesive layer, hard coating, anti-reflective layer, light emitting layer, and anti-glare layer, etc. The resin layer 13 may be provided with a plurality of layers, and preferably at least one layer is a layer having light diffusivity. If the resin layer 13 is a light-diffusing layer, the light-diffusing fine particles diffuse the light, so the reflected light from the metallic luster layer will diffuse, and it is easy to cause the reflectance in the SCE measurement of the CIE-XYZ color system Y is 1～60%. The layer having light diffusibility is preferably a layer containing light diffusive fine particles.

For example, when the resin layer 13 is an adhesive layer, the adhesive layer may also be a light-diffusing adhesive layer containing light-diffusing fine particles. Moreover, in the electromagnetic wave transmissive laminate, in addition to the adhesive layer, other resin layers may be provided according to the application, and the other resin layers may be layers having light diffusibility.

Fig. 3 is a schematic cross-sectional view of an electromagnetic wave permeable laminate according to an embodiment of the present invention. As shown in FIG. 3, the electromagnetic wave-permeable laminate 1 may include a base 10, an indium oxide-containing layer 11, a metal layer 12, a light diffusion adhesive layer 13a as a resin layer, and a hard coat layer 13b. The electromagnetic wave transmissive laminate 1 of the present embodiment is provided with an indium oxide-containing layer 11, a metal layer 12, and a light diffusion adhesive layer 13a on a base 10 provided with a hard coat layer 13b.

The electromagnetic wave transmissive laminated body 1 of this embodiment can also be used by sticking to a member to be adhered via the light-diffusing adhesive layer 13a. For example, it is possible to decorate the adhered member from the inside by attaching the electromagnetic wave permeable laminate 1 to a transparent adhered member via the light diffusion adhesive layer 13a. When the electromagnetic wave-permeable laminate 1 is attached to the surface of the transparent adhered member on the opposite side (hereinafter also referred to as the inner side) from the visible side (hereinafter also referred to as the outer side) via the light-diffusing adhesive layer 13a , The light diffusion adhesive layer 13a and the metal layer 12 are visible through the adhered member. Therefore, the electromagnetic wave-permeable laminate 1 of the present embodiment can obtain an excellent metallic appearance with high light diffusibility, metallic luster, and brightness suppressed. As the transparent adhered member, for example, a member made of glass or plastic can be used, but it is not limited to this.

The haze value of the resin layer is preferably 10% or more, more preferably 20% or more, and still more preferably 50% or more from the viewpoint of realizing the appearance of a dark color tone. By making the haze value of the resin layer 10% or more, it is easy to make the reflectance Y in the required range. In addition, by adjusting the haze value of the resin layer, the brightness L ^* value, hue a ^* value, and b ^* value of the obtained electromagnetic wave permeable laminate can be controlled. The haze value of the resin layer can be measured using a measuring device such as a spectrophotometer CM-2600d manufactured by Konica Minolta Co., Ltd., and can be measured using the method described in the examples.

The ratio of the thickness of the metallic luster layer to the thickness of the resin layer (the thickness of the metallic luster layer/the thickness of the resin layer) can be changed according to the type and quantity of the resin layer, and there is no particular limitation, as for the step absorbency during lamination From a viewpoint, it is preferably 0.0001 or more, more preferably 0.0003 or more, and still more preferably 0.001 or more. Furthermore, from the viewpoint of making the case thinner, it is preferably 0.01 or less, more preferably 0.006 or less, and still more preferably 0.003 or less. Furthermore, when a plurality of resin layers are provided, the thickness of the above-mentioned resin layer is the thickness of each resin layer. When the light diffusion adhesive layer is provided as the resin layer, the ratio of the thickness of the metallic luster layer to the thickness of the light diffusion adhesive layer (the thickness of the metallic luster layer/the thickness of the light diffusion adhesive layer) is the stage at the time of lamination From the viewpoint of poor absorbency, it is preferably 0.0001 or more, more preferably 0.0003 or more, and still more preferably 0.001 or more. Furthermore, from the viewpoint of making the case thinner, it is preferably 0.01 or less, more preferably 0.006 or less, and still more preferably 0.003 or less.

(Light diffusion adhesive layer) The light-diffusing adhesive layer containing light-diffusing fine particles can be formed of a base adhesive composition and light-diffusing fine particles. (1-1) Basic adhesive composition The base adhesive composition preferably contains a (meth)acrylic polymer (A) as a base polymer. The (meth)acrylic polymer (A) preferably contains an alkyl (meth)acrylate (a1) constituting the main skeleton of the (meth)acrylic polymer (A) as a monomer unit. In addition, (meth)acrylate means acrylate and/or methacrylate.

As said (meth)acrylic acid alkyl ester (a1), the one which has a linear or branched C1-C18 alkyl group is mentioned. For example, as the above-mentioned alkyl group, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, cyclohexyl, heptyl, 2-ethylhexyl, isooctyl, Nonyl, decyl, isodecyl, dodecyl, isomyristyl, lauryl, tridecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, etc. These can be used alone or in combination.

The compounding ratio of the above-mentioned alkyl (meth)acrylate (a1) is preferably 50% by mass or more with respect to all the constituent monomers (100% by mass) constituting the (meth)acrylic polymer (A), and more preferably It is 50 to 100% by mass, more preferably 60 to 100% by mass, and particularly preferably 70 to 90% by mass.

In order to improve adhesion or heat resistance, the (meth)acrylic polymer (A) preferably contains a monomer selected from the group consisting of a carboxyl group-containing monomer (a2), a hydroxyl group-containing monomer (a3), and a nitrogen-containing monomer (a4). One or more monomers in the composition group are used as monomer components.

As the carboxyl group-containing monomer (a2), those containing a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and a carboxyl group can be used without particular limitation. Examples of carboxyl group-containing monomers include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, methylene succinic acid, maleic acid, fumarate Alkenedioic acid, crotonic acid, methacrylic acid, etc., which can be used alone or in combination. Methylene succinic acid and maleic acid can use these anhydrides. Among them, acrylic acid and methacrylic acid are preferred, and acrylic acid is particularly preferred.

The compounding ratio of the above-mentioned carboxyl group-containing monomer (a2) is preferably 10% by mass or less, more preferably 0.05-10, relative to all the constituent monomers (100% by mass) constituting the (meth)acrylic polymer (A) % By mass, more preferably 0.1 to 10% by mass, particularly preferably 0.5 to 5% by mass.

As the hydroxyl group-containing monomer (a3), those containing a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and a hydroxyl group can be used without particular limitation. Examples of hydroxyl-containing monomers include: 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4 (meth)acrylate -Hydroxybutyl, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, etc. ( Hydroxyalkyl meth)acrylate; (4-hydroxymethylcyclohexyl)methyl (meth)acrylate and hydroxyalkyl cycloalkyl (meth)acrylate. Furthermore, hydroxyethyl (meth)acrylamide, allyl alcohol, 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, etc. can be mentioned. These can be used alone or in combination. Among them, hydroxyalkyl (meth)acrylate is preferred, and 2-hydroxyethyl (meth)acrylate is more preferred.

The compounding ratio of the above-mentioned hydroxyl group-containing monomer (a3) is preferably 20% by mass or less, more preferably 0.05 to 20 relative to all the constituent monomers (100% by mass) constituting the (meth)acrylic polymer (A) % By mass, more preferably 0.1 to 15% by mass, particularly preferably 1 to 15% by mass.

As the nitrogen-containing monomer (a4), those containing a polymerizable functional group having an unsaturated double bond such as a (meth)acryloyl group or a vinyl group and a functional group having a nitrogen atom can be used without particular limitation.

The mixing ratio of the nitrogen-containing monomer (a4) is preferably 20% by mass or less, more preferably 0.05 to 20 relative to all the constituent monomers (100% by mass) constituting the (meth)acrylic polymer (A) % By mass, more preferably 0.1 to 15% by mass, particularly preferably 1 to 15% by mass.

In the (meth)acrylic polymer (A), the alkyl (meth)acrylate (a1), the carboxyl group-containing monomer (a2), the hydroxyl group-containing monomer (a3), and the nitrogen-containing monomer are further excluded In addition to (a4), one or more comonomers can be introduced by copolymerization to improve adhesion or heat resistance. The comonomer has (meth)acrylic or vinyl groups and other unsaturated double bonds. Sexual functional group. Specific examples of such comonomers include, for example, caprolactone adducts of acrylic acid; styrene sulfonic acid or allyl sulfonic acid, sulfopropyl (meth)acrylate, and (meth)acrylic acid Sulfonic acid group-containing monomers such as oxynaphthalenesulfonic acid; phosphoric acid group-containing monomers such as 2-hydroxyethyl acryloyl phosphate, etc.

The ratio of the comonomers other than the above-mentioned carboxyl group-containing monomer (a2), hydroxyl group-containing monomer (a3), and nitrogen-containing monomer (a4) is not particularly limited, and is used to constitute the (meth)acrylic polymer (A) In all monomers, it is preferably 10% by mass or less, more preferably 0.1 to 10% by mass, and still more preferably 0.1 to 5% by mass.

The (meth)acrylic polymer (A) can be obtained by appropriately combining and polymerizing the above-mentioned monomers according to the purpose or required characteristics. The obtained (meth)acrylic polymer (A) may be any of random copolymers, block copolymers, and graft copolymers. The (meth)acrylic polymer (A) can be synthesized by any appropriate method. For example, it can be synthesized by referring to "The Chemistry and Application of Adhesion" by Mae Katsuhiko in the publication of Dainippon Book (Stock).

For example, as a polymerization method of the (meth)acrylic polymer (A), any appropriate method can be adopted. Specific examples include solution polymerization, bulk polymerization, emulsion polymerization, and various radical polymerizations.

The polymerization initiator, chain transfer agent, emulsifier, etc. used in radical polymerization are not particularly limited, and can be appropriately selected and used. Furthermore, the weight average molecular weight of the (meth)acrylic polymer can be controlled by the usage amount of the polymerization initiator and the chain transfer agent, and the reaction conditions, and the usage amount can be appropriately adjusted according to these types.

For example, in solution polymerization etc., as a polymerization solvent, ethyl acetate, toluene, etc. can be used, for example. As a specific example of solution polymerization, the reaction is performed by adding a polymerization initiator under an inert gas flow such as nitrogen, and is usually carried out under reaction conditions of about 50 to 70° C. for about 5 to 30 hours.

As thermal polymerization initiators used in solution polymerization, for example, azo initiators such as 2,2'-azobisisobutyronitrile; peroxide initiators, combined peroxides and The redox of the reducing agent is an initiator, etc., but is not limited by these.

The above-mentioned polymerization initiator may be used alone, or two or more kinds may be used in combination, and it is preferably about 1 part by mass or less with respect to 100 parts by mass of all monomer components constituting the (meth)acrylic polymer (A) , More preferably about 0.005 to 1 part by mass, and still more preferably about 0.02 to 0.5 part by mass.

Furthermore, for example, when 2,2'-azobisisobutyronitrile is used as the polymerization initiator to produce the (meth)acrylic polymer (A), the usage amount of the polymerization initiator is relative to the total monomer components. The amount is 100 parts by mass, preferably about 0.2 parts by mass or less, and more preferably about 0.06 to 0.2 parts by mass.

In addition, when the (meth)acrylic polymer (A) is produced by radiation polymerization, it can be produced by irradiating electron beams, UV and other radiation to polymerize the above-mentioned monomer components. In the case of the radiation polymerization by electron beam, it is not particularly necessary to include a photopolymerization initiator in the monomer component; in the case of the radiation polymerization by UV polymerization, the polymerization time can be shortened in particular In terms of its advantages, it is possible to include a photopolymerization initiator in the monomer component. A photopolymerization initiator can be used individually by 1 type or in combination of 2 or more types.

The weight average molecular weight of the (meth)acrylic polymer (A) used in the present invention is preferably 400,000 to 2.5 million, more preferably 600,000 to 2.2 million. By making the weight average molecular weight greater than 400,000, the durability of the adhesive layer can be satisfied or the cohesive force of the adhesive layer can be suppressed from becoming small, resulting in paste residue. In addition, the weight average molecular weight refers to a value calculated by polystyrene conversion measured by gel permeation chromatography (GPC). Furthermore, it is difficult to measure the molecular weight of (meth)acrylic polymers obtained by radiation polymerization.

The base adhesive composition used in the present invention may also contain a crosslinking agent. Examples of the crosslinking agent include organic crosslinking agents and polyfunctional metal chelate compounds. Examples of the organic crosslinking agent include isocyanate-based crosslinking agents, peroxide-based crosslinking agents, epoxy-based crosslinking agents, and imine-based crosslinking agents. The polyfunctional metal chelate is a covalent bond or coordinate bond between a polyvalent metal and an organic compound. Examples of polyvalent metals include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, And Ti. Examples of organic compounds include alkyl esters, alcohol compounds, carboxylic acid compounds, ether compounds, and ketone compounds. Examples of the atoms in the covalently bonded or coordinately bonded organic compounds include oxygen atoms. Among them, the crosslinking agent is preferably an isocyanate-based crosslinking agent.

The isocyanate-based crosslinking agent is typically a compound having two or more isocyanate groups in one molecule. Examples include isocyanate monomers such as toluene diisocyanate, chlorobenzene diisocyanate, tetramethylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, and hydrogenated diphenylmethane diisocyanate; and The isocyanate compound or isocyanurate compound, biuret type compound obtained by addition of isocyanate monomer and trimethylolpropane, etc.; furthermore, with polyether polyol or polyester polyol, acrylic polyol, poly Butadiene polyol, polyisoprene polyol, etc. are urethane prepolymer type isocyanates obtained by addition reaction. Particularly preferred is a polyisocyanate compound, which is one selected from the group consisting of hexamethylene diisocyanate, hydrogenated xylylene diisocyanate, and isophorone diisocyanate, or a polyisocyanate compound derived from these. Here, one selected from the group consisting of hexamethylene diisocyanate, hydrogenated xylylene diisocyanate, and isophorone diisocyanate or polyisocyanate compounds derived from these include: hexamethylene diisocyanate Methyl diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, polyol modified hexamethylene diisocyanate, polyol modified hydrogenated xylylene diisocyanate, trimer type hydrogenated benzene diisocyanate Methyl diisocyanate, and polyol modified isophorone diisocyanate, etc.

As the peroxide, any appropriate compound that can generate free radical active species by heating or light to promote crosslinking of the base polymer can be used. In consideration of workability and stability, peroxides with a 1-minute half-life temperature of 80°C to 160°C are preferred, and peroxides with a half-life temperature of 90°C to 140°C are more preferred. Specific examples of peroxides include: bis(2-ethylhexyl) peroxydicarbonate (1 minute half-life temperature: 90.6°C), bis(4-tertiarybutylcyclohexyl) peroxydicarbonate Ester (1 minute half-life temperature: 92.1°C), di-second butyl peroxydicarbonate (1 minute half-life temperature: 92.4°C), tert-butyl peroxyneodecanoate (1 minute half-life temperature: 103.5°C), Tertiary hexyl pivalate oxide (1 minute half-life temperature: 109.1°C), tertiary pivalate peroxide (1 minute half-life temperature: 110.3°C), dilaurin peroxide (1 minute half-life temperature: 116.4°C) ), di-n-octyl peroxide (1 minute half-life temperature: 117.4°C), 2-ethylhexanoic acid 1,1,3,3-tetramethylbutyl peroxide (1 minute half-life temperature: 124.3°C), over Di(4-methylbenzyl oxide) (1 minute half-life temperature: 128.2°C), Dibenzyl peroxide (1 minute half-life temperature: 130.0°C), tert-butyl peroxide isobutyrate (1 minute half-life) Temperature: 136.1°C), 1,1-bis(third hexylperoxy) cyclohexane (1 minute half-life temperature: 149.2°C), etc. Furthermore, the so-called half-life of peroxides is an indicator of the decomposition rate of peroxides, and refers to the time until the remaining amount of peroxides becomes half. Therefore, the so-called one-minute half-life temperature of peroxide refers to the temperature at which the remaining amount of peroxide becomes half within one minute. Regarding the decomposition temperature used to obtain the half-life in an arbitrary time or the half-life time at an arbitrary temperature, it has been recorded in the manufacturer’s catalog etc., for example, in the "Organic Peroxide Catalog 9th Edition (" May 2003)" etc.

The use amount of the crosslinking agent is preferably 0.01-20 parts by mass, more preferably 0.03-10 parts by mass relative to 100 parts by mass of the (meth)acrylic polymer (A). When the used amount of the crosslinking agent is less than 0.01 parts by mass, the cohesive force of the adhesive tends to be insufficient, and sometimes foaming occurs when heated. If the used amount of the crosslinking agent exceeds 20 parts by mass, the moisture resistance may be insufficient, and peeling may easily occur.

The above-mentioned base adhesive composition may also contain any appropriate additives. Examples of additives include antistatic agents, antioxidants, and coupling agents. The type, addition amount, and combination of additives can be appropriately set according to the purpose.

The content of the base adhesive composition in the light diffusion adhesive layer used in the present invention is preferably 50-99.7 mass%, more preferably 52-97% by mass, and still more preferably 70-97% by mass.

The refractive index of the above-mentioned base adhesive composition is preferably 1.44 or more, more preferably 1.44 to 1.60, and still more preferably 1.44 to 1.55. If the refractive index of the base adhesive composition is in the above-mentioned range, the difference in refractive index from the light diffusing fine particles described later can be made into the required range. As a result, a light-diffusing adhesive layer with excellent light diffusibility can be obtained after curing, which is preferable.

(1-2) Light diffusing fine particles The light-diffusing adhesive layer preferably has light-diffusing fine particles dispersed in an adhesive layer formed of the base adhesive composition. As the light diffusing fine particles, any appropriate ones can be used as long as the effects of the present invention can be obtained. Specific examples include inorganic microparticles, polymer microparticles, and the like. Among these, polymer microparticles are preferred.

Examples of the material of the aforementioned polymer particles include silicone resin, methacrylic resin (for example, polymethyl methacrylate), polystyrene resin, polyurethane resin, and melamine resin. These resins have excellent dispersibility to the above-mentioned basic adhesive composition and an appropriate refractive index difference with the above-mentioned basic adhesive composition, so a light-diffusing adhesive layer with excellent diffusion performance can be obtained. Among them, silicone resin and polymethyl methacrylate are particularly preferred.

The shape of the light diffusing fine particles may be, for example, a spherical shape, a flat shape, or an indefinite shape. The light diffusing fine particles may be used alone or in combination of two or more kinds.

The refractive index of the light diffusing fine particles used in the present invention is preferably lower than the refractive index of the above-mentioned base adhesive composition. The refractive index of the light diffusing fine particles is preferably 1.30 to 1.70, more preferably 1.40 to 1.65. If the refractive index of the light diffusing fine particles is in the above range, a light diffusing adhesive layer with excellent light diffusibility can be obtained, and the reflectance Y of the electromagnetic wave transmissive laminate can be easily adjusted to the desired range, which is preferable.

The absolute value of the refractive index difference between the light diffusing fine particles and the base adhesive composition is preferably more than 0 and 0.2 or less, more preferably more than 0 and 0.15 or less, and still more preferably 0.01 to 0.13.

The volume average particle diameter of the light diffusing fine particles is preferably about 1 to 5 μm, more preferably about 2 to 5 μm, and still more preferably about 2 to 4 μm. If the volume average particle diameter of the light diffusing fine particles is in the above range, a light diffusing adhesive layer with excellent light diffusibility can be obtained, and the reflectance Y of the electromagnetic wave permeable laminate can be easily brought into the desired range, which is preferable. In addition, the volume average particle diameter can be measured using, for example, an ultracentrifugal automatic particle size distribution measuring device.

The content of the light diffusing fine particles in the light diffusing adhesive layer is not particularly limited, but is preferably 0.3 to 50% by mass, more preferably 3 to 48% by mass, and still more preferably 3 to 30% by mass. By setting the blending amount of the light diffusing fine particles within the above range, a light diffusing adhesive layer with excellent light diffusing performance can be obtained. The light diffusion performance of the light diffusion adhesive layer can be controlled by adjusting the constituent material of the matrix (adhesive), the constituent material of the light diffusive particles, the volume average particle size, and the blending amount.

(1-3) Formation method of light diffusion adhesive layer The method for forming the adhesive layer is not particularly limited. For example, the following method may be used: coating the adhesive composition on various substrates, drying to remove the solvent, etc., and, if necessary, cross-linking treatment to form an adhesive Layer, and transfer the adhesive layer on the metallic luster layer; or directly coat the adhesive composition on the metallic luster layer to form an adhesive layer. For example, it can be formed by applying a light-diffusing adhesive composition on the metallic luster layer and drying to remove the solvent. The light-diffusing adhesive composition disperses light-diffusing fine particles in the base adhesive combination. Derived from material. When coating the light-diffusing adhesive composition, more than one solvent can also be appropriately added. In addition, when the above-mentioned basic adhesive composition is an active energy ray hardening type, the light diffusion adhesive layer can be formed by the following method: a prepolymer obtained by partially polymerizing a part of the above-mentioned basic adhesive composition is prepared, and The light-diffusing adhesive composition obtained by dispersing light-diffusing fine particles in the prepolymer is applied on the metallic luster layer, and the applied layer is irradiated with active energy rays such as ultraviolet rays. In addition, when the transparent conductive layer is provided, the light diffusion adhesive composition may be coated on the transparent conductive layer to form a light diffusion adhesive layer.

The thickness of the light diffusion adhesive layer is preferably 5 to 300 μm, more preferably 5 to 250 μm, still more preferably 10 to 250 μm, still more preferably 15 to 200 μm, particularly preferably more than 15 μm and is Below 150 μm. By setting the thickness of the light diffusion adhesive layer to 5 μm or more, it can follow the minute irregularities of the material to be bonded or the irregularities for imparting optical functions, so it is preferable. In addition, by making the thickness of the light-diffusing adhesive layer 300 μm or less, it is preferable from the viewpoint of thinning the casing. In addition, when the transparent adhesive layer is attached to the light-diffusion adhesive layer, the thickness of the light-diffusion adhesive layer is in terms of the effect of the physical properties of the light-diffusion adhesive without affecting the bonding effect on the peripheral components , Preferably about 5-100 μm, more preferably about 5-30 μm. Moreover, when the light-diffusion adhesive layer contains two or more layers, the total value of the thickness of all the light-diffusion adhesive layers should just be in the said range.

As a coating method of the light diffusion adhesive composition, various methods can be used. Specifically, for example, the following methods can be cited: roll coating, touch roll coating, gravure coating, reverse coating, roll brushing, spray coating, dip roll coating, bar coating, blade coating, air knife coating Cloth, curtain coating, die lip coating, and extrusion coating using die nozzle coaters, etc.

The heating and drying temperature is preferably about 30°C to 200°C, more preferably 40°C to 180°C, and still more preferably 80°C to 160°C. By setting the heating temperature within the above range, an adhesive layer with excellent adhesive properties can be obtained. The drying time can be suitably used at an appropriate time. The drying time is preferably about 5 seconds to 20 minutes, more preferably 30 seconds to 10 minutes, and still more preferably 1 minute to 8 minutes.

In the case where the above-mentioned base adhesive composition is an active energy ray curable adhesive, a light diffusion adhesive layer can be formed by irradiating active energy rays such as ultraviolet rays. For ultraviolet radiation, high-pressure mercury lamps, low-pressure mercury lamps, metal halide lamps, chemical light lamps, etc. can be used.

The various substrates described above function as a support, and, for example, a sheet that has undergone a peeling treatment can be used. As the release-treated sheet, it is preferable to use a silicone release liner.

When the adhesive sheet with the adhesive layer formed on the peeled-off sheet is exposed to the above-mentioned adhesive layer, the peeled-off sheet (separator) can also be used to protect the adhesive layer until it is used in practical applications. In actual application, the above-mentioned peeling-treated sheet is peeled off.

Examples of the constituent materials of the separator include: porous materials such as plastic films, paper, cloth, and non-woven fabrics, meshes, foamed sheets, metal foils, and suitable sheets such as laminates of these, etc. In terms of excellent surface smoothness, it is preferable to use a plastic film.

As the above-mentioned plastic film, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, poly(p-phenylene) can be mentioned. Ethylene diformate film, polybutylene terephthalate film, polyurethane film, ethylene-vinyl acetate copolymer film, etc.

The thickness of the aforementioned spacer is usually 5 to 200 μm, preferably about 5 to 100 μm. Optionally, the above-mentioned spacer may be subjected to mold release and antifouling treatment or coating type, using silicone-based, fluorine-based, long-chain alkyl-based or fatty amide-based mold release agents, silica powder, etc. Anti-static treatment of mixing type, vapor deposition type, etc. In particular, by appropriately performing peeling treatments such as silicone treatment, long-chain alkyl treatment, and fluorine treatment on the surface of the separator, the releasability from the adhesive layer can be further improved.

(Hard coating) The electromagnetic wave permeable laminate 1 may further include a hard coat layer. The hard coat layer 13b is formed of, for example, a hard coat composition. The hard coat composition contains a resin component, and is preferably composed of a resin component.

Examples of the resin component include curable resins, thermoplastic resins (for example, polyolefin resins), and the like, and curable resins are preferred.

The thickness of the hard coat layer is, for example, 0.5 μm or more, preferably 1.0 μm or more, and, for example, 10 μm or less, preferably 3.0 μm or less, and more preferably 2.0 μm or less. The thickness of the hard coat layer can be measured using a film thickness meter (digital dial gauge), for example.

＜7. Manufacturing of electromagnetic wave permeable laminated body＞ An example of the manufacturing method of the electromagnetic wave permeable laminate 1 will be described. Although not specifically stated, the same method can also be used for the case where a substrate other than the base film is used.

When the metallic luster layer is a metal layer, when the metal layer 12 is formed on the base 10, for example, methods such as vacuum evaporation and sputtering can be used. In the case of a metallic luster layer based on a resin layer, the metallic luster can be achieved by laminating resin layers with different refractive indexes. For example, resins with different refractive indexes can be produced by methods such as the feed block method or the multi-manifold method.

In addition, when the indium oxide-containing layer 11 is formed on the substrate 10, the indium oxide-containing layer 11 is formed by vacuum evaporation, sputtering, ion plating, or the like before forming the metallic luster layer. Among them, since the thickness can be strictly controlled even for a large area, sputtering is preferred.

Furthermore, when the indium oxide-containing layer 11 is provided between the substrate 10 and the metallic luster layer, it is preferable that the indium oxide-containing layer 11 and the metallic luster layer are in direct contact without intervening other layers.

＜8. Application of electromagnetic wave permeable laminate and metal thin film＞ Since the electromagnetic wave-permeable laminate of the present embodiment has electromagnetic wave permeability, it is preferably a device or article for transmitting and receiving electromagnetic waves, and parts thereof. Examples include: vehicle structural parts, vehicle-mounted products, electronic equipment housings, home appliance housings, structural parts, mechanical parts, various automotive parts, electronic equipment parts, furniture, kitchen supplies, and other household products Purpose, medical equipment, parts of construction materials, other structural parts or exterior parts, etc. More specifically, for vehicles, examples include: dashboards, console boxes, door handles, door trims, shift levers, pedals, glove boxes, bumpers, hoods, mudguards, trunks, doors, Roof, pillar, seat, steering wheel, ECU (Electronic Control Unit) box, electrical parts, engine peripheral parts, drive system/gear peripheral parts, intake/exhaust system parts, and cooling system parts, etc. As electronic equipment and home appliances, more specifically, include: refrigerators, washing machines, vacuum cleaners, microwave ovens, air conditioners, lighting equipment, electric water heaters, televisions, clocks, exhaust fans, projectors, speakers and other home appliances; computers, mobile phones , Smart phones, digital cameras, tablet PCs (personal computers, personal computers), walkmans, portable game consoles, chargers, batteries and other electronic information equipment. Example

Hereinafter, examples and comparative examples are given to explain the present invention more specifically. Regarding the electromagnetic wave permeable laminate 1, various samples were prepared, and the reflectance, haze value, sheet resistance, and radio wave permeability were evaluated. In addition, as the base 10, a base film was used. Sheet resistance is an evaluation of electromagnetic wave permeability. The details of the evaluation method are as follows.

(1) Reflectivity Attach the produced electromagnetic wave permeable laminate to a 1.3 mm thick glass plate (S200S200 manufactured by Matsunami Glass Industry Co., Ltd.), and use the spectrophotometer CM-2600d manufactured by Konica Minolta, with a wavelength of 380 Measure the reflectance Y (%) in the SCE measurement with visible light in the range of nm～780 nm. These measured values refer to the values of the above-mentioned glass plates. Furthermore, in the measurement, D65 was used as a standard light source, and the above-mentioned visible light was incident on the side where the metallic luster layer was provided on the surface of the obtained electromagnetic wave transmissive laminate.

(2) Haze value For the haze value of each light diffusion adhesive layer used in the examples and comparative examples, use the method specified in JIS 7136 and use a haze meter (trade name: HN-150, manufactured by Murakami Color Science Institute (Stock)) Determination.

(3) Sheet resistance Using the non-contact resistance measuring device NC-80MAP manufactured by Napson, in accordance with JIS-Z2316, the sheet resistance of the laminate of the metallic luster layer and the indium oxide-containing layer was measured by the eddy current measurement method. Based on the obtained sheet resistance value, the electromagnetic wave permeability of the electromagnetic wave permeable laminate is judged based on the following criteria.

(Evaluation criteria for sheet resistance) Less than 100 Ω/□: × (bad) Above 100 Ω/□: ○ (good)

(4) Evaluation method of film thickness First, as shown in Fig. 6, a square area 3 with a side length of 5 cm is appropriately extracted from the electromagnetic wave-permeable laminate, and the center lines A and B of the vertical and horizontal sides of the square area 3 are divided into 4 equal parts. , By this, a total of 5 points "a" to "e" are obtained, and these points are selected as the measurement site. After that, the cross-sectional image (transmission electron micrograph (TEM image)) shown in Fig. 7 of the selected measurement site was measured, and the metal parts containing more than 5 metal parts were extracted from the obtained TEM image. Viewing area of 12a. Divide the total cross-sectional area of the metal layer in the viewing angle area extracted at each of the 5 measurement locations by the width of the viewing area, and use the result as the film thickness of the metal layer in each viewing area. The average value of the film thickness of the metal layer in each viewing angle region is taken as the metal layer thickness (nm).

[Example 1] (Manufacturing of light diffusion adhesive composition) Add 100 parts by mass of butyl acrylate, 5 parts by mass of acrylic acid, 1 part by mass of hydroxyethyl acrylate, 0.1 parts by mass of 2,2'-azobisisobutyronitrile as a polymerization initiator, and 100 parts by mass of ethyl acetate. Into a four-necked flask equipped with a stirring blade, thermometer, nitrogen introduction tube, and condenser (concentration of monomer 50%), while slowly stirring, introduce nitrogen to replace with nitrogen, and maintain the liquid temperature in the flask at around 55°C , The polymerization reaction was carried out for 8 hours to prepare a solution of acrylic polymer 1 with a weight average molecular weight (Mw) of 1.8 million.

With respect to 100 parts by mass of the solid content of the acrylic polymer 1 solution obtained above, an isocyanate-based crosslinking agent (trade name: Corona L, trimethylolpropane/toluene diisocyanate trimer adduct, 0.66 parts by mass of Nippon Polyurethane Industry (manufactured by Nippon Polyurethane Industry Co., Ltd.), 0.3 parts by mass of benzoyl peroxide (Nyper BMT, manufactured by Nippon Oil & Fat Co., Ltd.), and silane coupling agent (trade name: KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.2 Parts by mass, thereby obtaining a base adhesive composition 1.

With respect to 100 parts by mass of the solid content of the obtained basic adhesive composition 1, silicone resin fine particles (trade name: Tospearl 145, volume average particle size: 4 μm, refractive index: 1.43, silicone resin fine particles, Made by Momentive Advanced Materials Co., Ltd.) 2 parts by mass as light-diffusing fine particles to prepare light-diffusing adhesive composition 1.

(Manufacturing of electromagnetic wave permeable laminate) A PET film (thickness 50 μm) with a hard coat layer was used as the base film. First, DC (direct current, direct current) magnetron sputtering is used to form an ITO layer with a thickness of 5 nm directly on the surface of the substrate film. The temperature of the base film when forming the ITO layer was set to 130°C. The content rate of tin oxide (SnO ₂ ) contained in ITO (content rate=(SnO ₂ /(In ₂ O ₃ +SnO ₂ ))×100) is 10% by mass.

Thereafter, alternating current sputtering (AC: 40 kHz) was used to form an aluminum (Al) layer with a thickness of 17 nm on the ITO layer. The obtained aluminum layer is a discontinuous layer. The temperature of the base film when forming the Al layer was set to 130°C. Thereafter, direct current sputtering (DC: 100 kHz, 1 μsec) was used to form an aluminum-doped zinc oxide (AZO) layer with a thickness of 70 nm on the aluminum layer, thereby obtaining a laminate 1. The temperature when forming the AZO layer was set to 130°C. In addition, when the radio wave transmission attenuation of the obtained laminate 1 was measured, it was -0.02 dB.

The light-diffusing adhesive composition obtained above was applied to a polyethylene terephthalate film treated with a silicone-based release agent in such a way that the thickness of the adhesive layer after drying became 20 μm (Mitsubishi One side of a polyester film manufactured by Chemical Co., Ltd., trade name "MRF-38", isolation film), and dried at 155°C for 1 minute to form an adhesive layer on the surface of the isolation film. After that, the adhesive layer formed on the isolation film is transferred to the metal layer side surface of the laminate 1 obtained above, thereby obtaining an electromagnetic wave permeable laminate.

[Examples 2 to 5] Except having changed the amount of silicone resin fine particles used in the preparation of the light-diffusing adhesive composition as described in Table 1, the electromagnetic wave-permeable laminates of Examples 2 to 5 were produced in the same manner as in Example 1.

[Comparative Example 1] Except that silicone resin fine particles were not added in the preparation of the light diffusion adhesive composition, the electromagnetic wave permeable laminate of Comparative Example 1 was produced in the same manner as in Example 1. The obtained aluminum layer is a discontinuous layer.

[Examples 6-10] As described in Table 1, the amount of silicone resin fine particles and the film thickness of the aluminum layer used in the preparation of the light diffusion adhesive composition were changed, and the electromagnetic waves of Examples 6 to 10 were produced in the same manner as in Example 1, except that the amount of fine silicone resin particles used in the preparation of the light diffusion adhesive composition was changed. Permeable laminate. The obtained aluminum layer is a discontinuous layer.

[Comparative Example 2] Except that silicone resin fine particles were not added in the preparation of the light diffusion adhesive composition, the electromagnetic wave permeable laminate of Comparative Example 2 was produced in the same manner as in Example 6. The obtained aluminum layer is a discontinuous layer. The evaluation results are shown in Table 1 below.

[Table 1] Table 1 Metal layer (metal: thickness) Haze value of light diffusion adhesive layer Number of particles Determination Y(D65) (%) Sheet resistance Comparative example 1 Al: 17 nm hz0% 0 SCE 0.01 〇 Example 1 Al: 17 nm hz20% 2 SCE 3.3 〇 Example 2 Al: 17 nm hz40% 6 SCE 10.5 〇 Example 3 Al: 17 nm hz60% 9 SCE 16.6 〇 Example 4 Al: 17 nm hz70% 15 SCE 21.8 〇 Example 5 Al: 17 nm hz85% 29 SCE 30.8 〇 Comparative example 2 Al: 35 nm hz0% 0 SCE 0.01 〇 Example 6 Al: 35 nm hz20% 2 SCE 4.7 〇 Example 7 Al: 35 nm hz40% 6 SCE 13.7 〇 Example 8 Al: 35 nm hz60% 9 SCE 21.4 〇 Example 9 Al: 35 nm hz70% 15 SCE 28.2 〇 Example 10 Al: 35 nm hz85% 29 SCE 39.7 〇

It can be seen from Table 1 that in Examples 1 to 10, the reflectance Y was in the range of 1 to 60%, and the brilliance was suppressed, and the electromagnetic wave permeable laminate with good metallic appearance was obtained. On the other hand, the reflectance Y of the electromagnetic wave-permeable laminates of Comparative Examples 1 and 2 was less than 1%, and the metal appearance was inferior to those of Examples 1-10.

Furthermore, it is believed that metals with relatively low melting points such as zinc (Zn), lead (Pb), copper (Cu), silver (Ag), etc., other than aluminum (Al) used in the above embodiments The discontinuous structure is formed by the same method.

The present invention is not limited to the above-mentioned embodiments, and may be appropriately modified and embodied within a scope that does not depart from the spirit of the invention.

The present invention has been described in detail with reference to specific embodiments, but the industry should understand that various changes or modifications can be added without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Japanese Patent Application No. 2019-146674) filed on August 8, 2019, and the content is incorporated herein by reference. [Industrial availability]

The electromagnetic wave-permeable laminate of the present invention can be used for devices or articles that transmit and receive electromagnetic waves, and parts thereof. For example, it can also be used for structural parts for vehicles, equipment for vehicles, housings for electronic equipment, housings for household appliances, structural parts, mechanical parts, various automotive parts, electronic equipment parts, furniture, kitchen supplies, and other household products Applications, medical equipment, parts of construction materials, other structural parts, or exterior parts, etc., which require both design and electromagnetic wave permeability.

1: Electromagnetic wave permeable laminate 10: Matrix 11: Indium oxide layer 12: Metal layer 12a: part 12b: gap 13: Resin layer 13a: Light diffusion adhesive layer 13b: Hard coating 14: barrier layer

Fig. 1 is a schematic cross-sectional view of an electromagnetic wave permeable laminate according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of an electromagnetic wave permeable laminate according to an embodiment of the present invention. Fig. 3 is a schematic cross-sectional view of an electromagnetic wave permeable laminate according to an embodiment of the present invention. Fig. 4 is a schematic cross-sectional view of an electromagnetic wave permeable laminate according to an embodiment of the present invention. Fig. 5 is an electron micrograph of the surface of the electromagnetic wave transmissive laminate according to one embodiment of the present invention. Fig. 6 is a diagram for explaining a method of measuring the film thickness of the metal layer of the electromagnetic wave permeable laminate according to one embodiment of the present invention. FIG. 7 is a diagram showing a transmission electron micrograph (TEM image) of a cross-section of a metal layer in an embodiment of the present invention.

1: Electromagnetic wave permeable laminate

10: Matrix

12: Metal layer

12a: part

12b: gap

13: Resin layer

Claims (14)

An electromagnetic wave-permeable laminate, comprising a base, a metallic luster layer formed on the base, and a resin layer, The reflectance Y of the reflected light within the wavelength range of 380 nm to 780 nm in the SCE measurement of the CIE-XYZ color system is 1 to 60%. The electromagnetic wave permeable laminate of claim 1, wherein the metallic luster layer is a metal layer, The above-mentioned metal layer includes a plurality of parts at least part of which are in a discontinuous state. The electromagnetic wave permeable laminate of claim 2, wherein the metal layer is a layer containing aluminum or aluminum alloy. The electromagnetic wave permeable laminate according to any one of claims 1 to 3, wherein the resin layer includes a layer containing light diffusing fine particles. The electromagnetic wave permeable laminate according to any one of claims 1 to 4, wherein the resin layer includes a light diffusion adhesive layer. The electromagnetic wave permeable laminate according to any one of claims 1 to 5, wherein an indium oxide-containing layer is further provided between the substrate and the metallic luster layer. The electromagnetic wave permeable laminate of claim 6, wherein the indium oxide-containing layer is provided in a continuous state. The electromagnetic wave permeable laminate of claim 6 or 7, wherein the indium oxide-containing layer includes any one of indium oxide (In ₂ O ₃ ), indium tin oxide (ITO), or indium zinc oxide (IZO). The electromagnetic wave permeable laminate according to any one of claims 6 to 8, wherein the thickness of the indium oxide-containing layer is 1 nm to 1000 nm. The electromagnetic wave permeable laminate according to any one of claims 6 to 9, wherein the thickness of the metallic luster layer is 5 nm to 100 nm. The electromagnetic wave permeable laminate of any one of claims 6 to 10, wherein the ratio of the thickness of the metallic luster layer to the thickness of the indium oxide-containing layer (thickness of the metallic luster layer/thickness of the indium oxide-containing layer) It is 0.02～100. For example, the electromagnetic wave-permeable laminate of any one of claims 1 to 11 has a sheet resistance of 100 Ω/□ or more. The electromagnetic wave permeable laminate of claim 2, wherein the plurality of parts are formed in an island shape. The electromagnetic wave permeable laminate according to any one of claims 1 to 13, wherein any one of the above-mentioned base system substrate film, resin molded product substrate, glass substrate, or articles that should be imparted with metallic luster.

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