TW202120323A - Multilayer body - Google Patents

Abstract

The present invention relates to a multilayer body which is sequentially provided with a base material film, an optical adjustment layer, a barrier layer and an adhesive layer in this order, wherein: the optical adjustment layer has a refractive index of 1.75 or more, while containing at least one substance that is selected from the group consisting of metal oxides, metal nitrides and metal sulfides; the barrier layer contains a metal oxide and/or a metal nitride; and the adhesive layer is formed of a transparent adhesive.

Description

Layered body

The present invention relates to a laminated body.

Previously, there have been known laminates attached to an article to decorate the article. As such a laminate, for example, a decorative film having electromagnetic wave permeability and metallic luster, which is laminated by a base film, a metal layer, an adhesive layer, etc., is known.

This kind of film has a sense of luxury in appearance due to its metallic luster, and also has electromagnetic wave permeability, so it is suitable for decorating devices that transmit and receive radio waves. For example, it is used in the housing of mobile phones, smart phones, computers, etc., or the decoration of the front of cars. Furthermore, in recent years, with the development of IoT (Internet of Things) technology, home appliances or household appliances have also provided communication functions, so that the application of such films in a wider range of fields is also expected by people.

For example, Patent Document 1 discloses a metallic luster non-conductive transfer film, which is a transfer film that is transferred onto a molded object, and is characterized by having: a protective layer and a protective layer laminated on the protective layer A printed layer, a non-conductive metal vapor-deposited layer vapor-deposited on the above-mentioned printed layer in an island-like structure, and an adhesive layer laminated on the above-mentioned metal vapor-deposited layer. Prior art literature Patent literature

Patent Document 1: Japanese Patent Special Form No. 2014-509268

[The problem to be solved by the invention]

Regarding such a laminate, it is sometimes desirable to color the appearance. As a method to meet such a demand, a method of further laminating an optical adjustment layer as a layer constituting the laminated body can be considered. Regarding a laminate having an optical adjustment layer, it is sometimes desirable to have a configuration with an adhesive layer on the optical adjustment layer, for example, a configuration with a substrate, an optical adjustment layer, and an adhesive layer in this order. For example, when the adhered member is to be decorated from the inside (the side opposite to the visible surface), a laminate (film) of such a structure is required. If the film of this structure is pasted on the inside of a transparent adhered member and used, the adhered member can be given an appearance colored by the optical adjustment layer. In addition, the film is located inside the adhered member, so it is not easily damaged. Furthermore, the adhered member is located on the outside, so that the texture of the adhered member can be fully displayed in the product.

However, this kind of film has the following problem: ultraviolet rays, temperature, humidity and other factors can cause deterioration of the optical adjustment layer, resulting in a change in its appearance.

The present invention was completed in view of the above-mentioned problems, and its object is to provide a laminate that can decorate the adhered member to give it a colored appearance, and further suppress the appearance change caused by various factors such as ultraviolet rays, temperature, and humidity. [Technical means to solve the problem]

The laminated system of the present invention that solves the above problems sequentially includes a substrate film, an optical adjustment layer, a barrier layer, and an adhesive layer, wherein the optical adjustment layer contains a metal oxide, a metal nitride, and a metal sulfide. At least one layer in the group with a refractive index above 1.75, the barrier layer is a layer containing metal oxide and/or metal nitride, and the adhesive layer is a layer containing a transparent adhesive. In one aspect of the laminate of the present invention, a metal layer may be further provided between the base film and the optical adjustment layer. In one aspect of the laminated body of the present invention, the metal layer may include at least a plurality of portions in a discontinuous state. In one aspect of the laminate of the present invention, an indium oxide-containing layer may be further provided between the base film and the metal layer. In one aspect of the laminate of the present invention, the optical adjustment layer may contain Si and/or Nb. In one aspect of the laminate of the present invention, the barrier layer may contain SiO ₂ . In one aspect of the laminated body of the present invention, it is feasible to bond the laminated body to the glass plate via an adhesive layer, and then irradiate visible light in the range of 380 nm to 780 nm to the laminated body through the glass plate Obtain the reflection spectrum, and irradiate the laminated body attached to the glass plate with ultraviolet light through the glass plate for 24 hours, and then irradiate the visible light in the range of 380 nm to 780 nm through the glass plate to the laminated body to obtain the reflection spectrum. , The color difference ΔE calculated using the above two reflection spectra is 3 or less. In one aspect of the laminated body of the present invention, it is feasible to bond the laminated body to the glass plate via an adhesive layer, and then irradiate visible light in the range of 380 nm to 780 nm to the laminated body through the glass plate Obtain the reflection spectrum, and after keeping the laminated body attached to the glass plate in an environment with a temperature of 65°C and a humidity of 90% for 500 hours, the visible light with a wavelength of 380 nm to 780 nm is irradiated to the laminated layer through the glass plate The reflectance spectrum is obtained by mass, and the minimum wavelength difference between the above two reflectance spectra is 15 nm or less. [Effects of Invention]

The laminated body of the present invention can decorate the adhered member to give it a colored appearance, and further can suppress the appearance change caused by various factors such as ultraviolet rays, temperature, and humidity.

Hereinafter, the mode for implementing the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by embodiment demonstrated below. In addition, in the following drawings, members and parts that perform the same function may be described with the same reference numerals, and repeated descriptions may be omitted or simplified. In addition, the embodiments described in the drawings are those modeled in order to clearly explain the present invention, and do not necessarily represent actual dimensions or scales accurately.

[Layered body] Fig. 1 shows a schematic cross-sectional view of a laminate according to an embodiment of the present invention. The laminate 1 of this embodiment includes a base film 10, an optical adjustment layer 13, a barrier layer 14, and an adhesive layer 15 in this order.

＜Base film＞ The base film 10 can be used, for example, including polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate, polyamide, polyvinyl chloride, and polycarbonate. Ester (PC), cyclic olefin polymer (COP), polystyrene, polypropylene (PP), polyethylene, polycyclic olefin, polyurethane, acrylic (PMMA, polymethyl methacrylate) , ABS (acrylonitrile-butadiene-styrene resin) and other homopolymer or copolymer films. These components will not affect the brilliance or radio wave transmittance described below. However, since various layers will be formed on the substrate film 10 later, it is preferably one that can withstand high temperatures such as evaporation or sputtering. Therefore, among the above materials, for example, polyethylene terephthalate, Polyethylene naphthalate, acrylic, polycarbonate, cyclic olefin polymer, ABS, polypropylene, polyurethane. Among them, in view of a good balance between heat resistance and cost, polyethylene terephthalate, cycloolefin polymer, polycarbonate or acrylic is preferred. The base film 10 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 addition, in order to enhance the adhesion with the layer formed on the base film 10, plasma treatment or easy bonding treatment, etc. may also be implemented. In addition, the base film 10 may also have light-shielding properties, and the details will be described below.

On the base film 10, a smooth or anti-glare hard coating layer may be formed as needed. By providing a hard coat layer, scratch resistance can be improved. In particular, by providing a smooth hard coating layer, the metallic luster can be improved when the metal layer 12 described below is provided. On the other hand, by providing an anti-glare hard coating layer, glare can be prevented. The hard coat layer can be formed by applying a solution containing a curable resin. Examples of curable resins include thermosetting resins, ultraviolet curing resins, electron beam curing resins, and the like. As the type of curable resin, for example, polyester-based, acrylic-based, urethane-based, acrylic urethane-based, amide-based, silicone-based, silicate-based, epoxy-based, Various resins such as melamine-based, oxetane-based, and acrylic urethane-based resins. One or two or more of these curable resins can be appropriately selected and used. Among them, the self-hardness is high, ultraviolet curing is possible, and the productivity is excellent, and acrylic resins, acrylic urethane resins, and epoxy resins are preferred.

<Indium oxide-containing layer> When the laminated body 1 includes the metal layer 12 described below, the indium oxide-containing layer 11 may be provided between the base film 10 and the metal layer 12. As the indium oxide-containing layer 11, indium oxide (In ₂ O ₃ ) itself can be used, or metals containing indium and other than indium such as indium tin oxide (ITO) or indium zinc oxide (IZO) can also be used. (Second metal) composite oxide. However, in order to make the discharge stability in the sputtering step higher, it is more preferable to contain ITO or IZO containing the second metal. By using the indium oxide-containing layer 11, it is easy to make the metal layer 12 into an island-shaped discontinuous structure, and aluminum, which was not easy to become a discontinuous structure in the past, can also be easily applied to the metal layer 12. The details will be described below.

When ITO is used in the indium oxide-containing layer 11, _{the weight ratio of tin oxide (SnO 2} ) contained in the ITO, that is, the content ratio (content ratio=(SnO ₂ /(In ₂ O ₃ +SnO ₂ ))×100) It is not particularly limited, and for example, it is 2.5 wt% to 30 wt%, more preferably 3 wt% to 10 wt%.

In addition, when IZO is used in the indium oxide-containing layer 11, the weight ratio of zinc oxide (ZnO) contained in IZO, that is, the content ratio (content ratio=(ZnO/(In ₂ O ₃ +ZnO))×100), for example It is 2 wt% to 20 wt%.

From the viewpoint of electromagnetic wave permeability and productivity, 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. On the other hand, in order to easily form the metal layer 12 in a discontinuous state, the thickness of the indium oxide-containing layer 11 is preferably 1 nm or more, more preferably 2 nm or more, and still more preferably 5 nm or more.

＜Metal layer＞ The laminate 1 may further include a metal layer 12 between the base film 10 and the optical adjustment layer 13. The laminated body 1 further includes the metal layer 12, so that it can become a metallic luster film. By setting it as such a structure, it is possible to give a colored metallic luster appearance to an article to be decorated (a member to be adhered). When the laminated body 1 is provided with the metal layer 12, the metal layer 12 is formed on the base film 10 (when the indium oxide-containing layer 11 is provided, it is formed on the indium oxide-containing layer 11). In this case, the metal layer 12 preferably includes at least a plurality of portions 12a in a discontinuous state. At least a part of these parts 12a is in a discontinuous state, in other words, at least part is separated by a gap 12b. If the plurality of parts 12a are separated by the gap 12b, the sheet resistance of the laminated body 1 becomes large, and the interaction with the electric wave is small, so that the electric wave can be transmitted. Furthermore, the "discontinuous state" in this specification means a state where a plurality of parts 12a are separated from each other by gaps 12b, and as a result, they are electrically insulated from each other. With electrical insulation, the sheet resistance of the metal layer 12 increases, and radio wave permeability can be obtained. That is, with the metal layer 12 formed in a discontinuous state, sufficient brightness can be ensured, and radio wave transmission can also be ensured.

The discontinuous structure including a plurality of portions 12a and gaps 12b is not particularly limited. For example, an island structure or a cracked structure can be exemplified, but from the viewpoint of productivity, an island structure is preferable.

The island-like structure is a structure in which metal particles are independent of each other and are densely spread in a state of being slightly separated or partially in contact with each other. The metal layer 12 of the island-like structure can be formed by, for example, forming a metal on the base film 10 by vapor deposition, sputtering, or the like (formed on the indium oxide-containing layer 11 when the indium oxide-containing layer 11 is provided). The details of the mechanism by which the metal layer 12 formed by vapor deposition or sputtering becomes a discontinuous state on the base film 10 are not clear, but it is considered that the ease of formation of the discontinuous structure and the imparted metal layer 12 The surface diffusivity on the substrate is related. Therefore, it is considered that when the substrate temperature is higher, the wettability of the metal layer 12 with respect to the substrate is lower, and the melting point of the metal constituting the metal layer 12 is lower, it is easier to form a discontinuous structure. Therefore, in the following embodiments, aluminum (Al) is used as the metal constituting the metal layer 12, but for other metals such as zinc (Zn), lead (Pb), copper (Cu), silver (Ag), etc., the melting point is relatively low It is considered that the metal can also be formed into a discontinuous structure by the same method. Furthermore, it is considered that the reason why the metal layer 12 is easily formed into an island-shaped discontinuous structure by the indium oxide-containing layer 11 is that the indium oxide-containing layer 11 improves the surface diffusibility of the metal constituting the metal layer 12.

The thickness of the metal layer 12 of the island-like structure is not particularly limited. In order to improve the metallic luster, it is preferably 20 nm or more, and more preferably 30 nm or more. On the other hand, in order to improve the electromagnetic wave permeability, the thickness of the metal layer 12 of the island-like structure is preferably set to 100 nm or less, and more preferably set to 70 nm or less. In addition, the circle equivalent diameter of the metal portion 12a in the metal layer 12 of the island-like structure is not particularly limited, and is usually about 10 to 1000 nm. Moreover, the distance between each part 12a is not specifically limited, Usually, it is about 10-1000 nm. These can be obtained from, for example, SEM (Scanning Electron Microscope) images.

The cracked structure is a structure in which the metal film is broken by cracks. For the metal layer 12 of the cracked structure, for example, a metal thin film layer can be provided on the base film 10 (on the indium oxide-containing layer when the indium oxide-containing layer 11 is provided), and the metal thin film layer may be cracked by bending and stretching. And formed. At this time, by providing a brittle layer containing a material that is poorly stretchable, that is, easily cracked due to stretching, between the base film 10 and the metal thin film layer, the metal layer 12 with a cracked structure can be easily formed.

The type of metal constituting the metal layer 12 is not particularly limited, and it may be one type of metal, or two or more types of metals. As mentioned above, it is believed that the ease of formation of the discontinuous structure is related to the surface diffusibility on the substrate (substrate film), and the substrate temperature is higher, the wettability of the metal layer relative to the substrate is small, and the material of the metal layer When the melting point is lower, it is easier to form a discontinuous structure. Therefore, from this point of view, it is preferable that the metal layer contains a metal with a relatively low melting point, for example, it preferably contains a metal selected from the group consisting of Al, Zn, Pb, Cu, and Ag. Any one of at least one metal in the group consisting of and an alloy containing the metal as a main component. In particular, for reasons such as brightness, stability, and price, it is preferable that the metal layer contains Al or an Al alloy. In addition, when an Al alloy is used, it is preferable to set the Al content to 50% by mass or more.

When the laminate 1 is provided with the indium oxide-containing layer 11, the ratio of the thickness of the metal layer 12 to the thickness of the indium oxide-containing layer 11 (thickness of the metal layer/thickness of the indium oxide-containing layer) is preferably in the range of 0.1-100 , More preferably in the range of 0.3 to 35.

＜Optical adjustment layer＞ The optical adjustment layer 13 is a layer containing at least one selected from the group consisting of metal oxides, metal nitrides, and metal sulfides, and having a refractive index of 1.75 or more. If the refractive index of the optical adjustment layer 13 is 1.75 or more, a colored appearance can be obtained. In order to obtain a deeper appearance, the refractive index of the optical adjustment layer 13 is preferably 1.8 or more, more preferably 1.9 or more. In addition, from the viewpoint of thickness controllability, the refractive index of the optical adjustment layer 13 is preferably 3.5 or less, and more preferably 3.0 or less. In addition, the optical adjustment layer 13 may be a laminate of layers with different refractive indexes.

The material constituting the optical adjustment layer 13 is not particularly limited, and at least one selected from the group consisting of metal oxides, metal nitrides, and metal sulfides can be suitably used. Furthermore, the metal elements contained in the metal oxides, metal oxides, and metal sulfides referred to herein include semi-metal elements such as Si. In addition, at least one selected from the group consisting of metal oxides, metal nitrides, and metal sulfides includes metal oxynitride, metal oxysulfide, and metal sulfur nitride. In addition, the metal oxide may be an oxide of a single metal element (single oxide), or an oxide of a plurality of metal elements (complex oxide). Similarly, the metal nitride can be the nitride of a single metal element (single nitride), or the nitride of multiple metal elements (complex nitride), and the metal sulfide can be the sulfide of a single metal element (single sulfide). It can also be a sulfide of a plurality of metal elements (complex sulfide). As the material of the optical adjustment layer 13, more specifically, for example, CeO ₂ (2.30), Nb ₂ O ₃ (2.15), Nb ₂ O ₅ (2.20), SiN _x (2.03), Sb ₂ O ₃ (2.10), TiO ₂ (2.35), Ta ₂ O ₅ (2.10), ZrO ₂ (2.05), ZnO (2.10), ZnS (2.30), etc. [The values in parentheses for the above materials are the refractive index]. In particular, the optical adjustment layer 13 preferably contains Si and/or Nb, for example, preferably contains Nb ₂ O ₅ and/or SiN _X , and more preferably is composed of Nb ₂ O ₅ and/or SiN _X.

The thickness of the optical adjustment layer 13 is preferably 10 nm to 1000 nm. From the viewpoint of cost, it is more preferably 800 nm or less, and still more preferably 500 nm or less. Moreover, from the viewpoint of the hue, it is preferably 15 nm or more, more preferably 20 nm or more, and still more preferably 30 nm or more.

＜Barrier layer＞ The barrier layer 14 is a layer containing metal oxide and/or metal nitride. Furthermore, the term “metal oxide” and the metal element contained in the metal oxide include semi-metal elements such as Si. In addition, the metal oxide and/or metal nitride include metal oxynitride. In addition, the metal oxide may be an oxide of a single metal element (single oxide), or an oxide of a plurality of metal elements (complex oxide). Similarly, the metal nitride can be a nitride of a single metal element (single nitride), or a nitride of a plurality of metal elements (complex nitride). The present inventors found that the appearance change of the laminate 1 is caused by the following reasons. That is, when the laminate 1 is exposed to ultraviolet rays (UV rays) or placed in a high-temperature and high-humidity environment, the optical adjustment layer 13 and the adhesive layer 15 responses. Therefore, by disposing the barrier layer 14 between the optical adjustment layer 13 and the adhesive layer 15 to suppress their reaction, the appearance change of the laminate 1 can be suppressed.

The material for forming the barrier layer 14 is not particularly limited, as long as it is a material that is transparent and does not react with the adhesive layer 15 and the optical adjustment layer 13, for example, SiO ₂ , Al ₂ O ₃ , AZO, etc. are preferred, preferably It contains SiO ₂ , and is more preferably composed of SiO ₂ .

From the viewpoint of transparency, the barrier layer 14 preferably has low optical absorption. For example, the absorption rate of the barrier layer to light with a wavelength of 550 nm is preferably 20% or less, more preferably 10% or less, and still more preferably 5% or less. The absorption rate of the barrier layer can be measured by the method shown below.

(Measurement method of absorptance) The laminated body 1 is attached to the glass plate via the adhesive layer 15, and the visible light with a wavelength in the range of 380 nm to 780 nm is irradiated to the laminated body 1 through the glass plate using a spectrophotometer U-4100 manufactured by Hitachi High-Technologies Corporation. Obtain the reflection spectrum and transmission spectrum, subtract the reflectance and transmittance at the wavelength of 550 nm in the reflection spectrum and transmission spectrum from 1, and use the obtained value as the absorbance.

In order to suppress the reaction between the optical adjustment layer 13 and the adhesive layer 15, the thickness of the barrier layer is preferably 10 nm or more, more preferably 20 nm or more, and particularly preferably 40 nm or more. On the other hand, from the viewpoint of flexibility, it is preferably 300 nm or less, more preferably 200 nm or less, and particularly preferably 100 nm or less.

In addition, the laminated body 1 may include a plurality of barrier layers. For example, a barrier layer may also be provided between the base film (the metal layer when the metal layer 12 is provided) and the optical adjustment layer 13.

＜Adhesive layer＞ The adhesive layer 15 is a layer containing a transparent adhesive. The laminated body 1 of this embodiment can be used, for example, by sticking to the inner side (the side opposite to the visible side) of the transparent adhered member via the adhesive layer 15 to decorate the adhered member from the inner side.

The adhesive forming the adhesive layer 15 is not particularly limited, as long as it is a transparent adhesive. For example, acrylic adhesives, rubber-based adhesives, silicone-based adhesives, polyester-based adhesives, and urethanes can be used alone. Any one of an ester-based adhesive, an epoxy-based adhesive, and a polyether-based adhesive, or a combination of two or more of them can be used. From the viewpoints of transparency, processability, durability, etc., it is preferable to use an acrylic adhesive.

Although the thickness of the adhesive layer 15 is not particularly limited, the visible light transmittance, film thickness accuracy, and flatness can be improved by making it thinner. Therefore, it is preferably 100 μm or less, more preferably 75 μm or less, and more It is preferably 50 μm or less.

The total light transmittance of the adhesive layer 15 as a whole is not particularly limited, but it is preferably 10% or more, more preferably 30% or more, and still more preferably 50 as measured at any visible light wavelength according to JIS K7361. %the above. The higher the total light transmittance of the adhesive layer 15 is, the better.

The adhesive layer 15 is preferably protected by a release liner before being attached to the adhered member.

＜Other floors＞ In addition to the base film 10, the indium oxide-containing layer 11, the metal layer 12, the optical adjustment layer 13, the barrier layer 14, and the adhesive layer 15, the laminated body 1 of this embodiment may also be provided with other layers according to the application, as long as the function is utilized. The effect of the invention is sufficient. For example, the laminate 1 of the present embodiment may be provided with a light-shielding layer that does not have visible light transmittance on the surface of the base film 10 opposite to the side on which the optical adjustment layer 13 is formed. By providing a light-shielding layer, for example, when the laminated body 1 of the present embodiment is used to decorate the casing of an electronic device, it is possible to prevent the circuit inside the casing from being visually recognized through the laminated body 1. The material of the light-shielding layer is not particularly limited. For example, the material exemplified as the material that can be used for the base film 10 can be colored black and used. Moreover, in the laminated body which does not have a light-shielding layer, by making the base film 10 light-shielding, the same effect as the case where a light-shielding layer is provided can also be exhibited.

＜UV resistance and high temperature and humidity resistance＞ As one of the factors that cause the optical adjustment layer 13 and the adhesive layer 15 to react, ultraviolet rays, temperature, and humidity can be cited. The laminated body 1 of this embodiment is provided with the barrier layer 14, and even when exposed to ultraviolet rays or exposed to a high temperature and high humidity environment, the reaction between the optical adjustment layer 13 and the adhesive layer 15 is not easy to proceed. . Ultraviolet resistance (difficulty of the reaction between the optical adjustment layer 13 and the adhesive layer 15 when exposed to ultraviolet rays) or high temperature and humidity resistance (optical adjustment when exposed to a high temperature and high humidity environment) of the laminate 1 of this embodiment The difficulty of the reaction between the layer 13 and the adhesive layer 15) can be evaluated using reflectance spectroscopy, for example.

For example, the laminated body 1 is bonded to a glass plate via the adhesive layer 15, and then visible light with a wavelength in the range of 380 nm to 780 nm is irradiated to the laminated body 1 through the glass plate to obtain a reflection spectrum (hereinafter also referred to as "initial Reflectance spectrum"), and after exposing the laminated body 1 attached to the glass plate to ultraviolet rays or high temperature and high humidity, visible light with a wavelength ranging from 380 nm to 780 nm is irradiated to the laminated body 1 through the glass plate. Obtain the reflection spectrum (hereinafter also referred to as "reflection spectrum after ultraviolet radiation" or "reflection spectrum after exposure to high temperature and high humidity"). By comparing the above two reflection spectra, the resistance to ultraviolet light or resistance can be High temperature and high humidity are evaluated.

In the laminated body of the embodiment of the present invention, the laminated body is bonded to a glass plate via the adhesive layer, and then visible light having a wavelength in the range of 380 nm to 780 nm is irradiated to the laminated body through the glass plate. Reflect spectrum, and irradiate ultraviolet light through the glass plate to the laminated body bonded to the glass plate for 24 hours, and then irradiate visible light in the range of 380 nm to 780 nm through the glass plate to the laminated body To obtain the reflection spectrum, the color difference ΔE calculated using the above two reflection spectra is preferably 3 or less. From the viewpoint of ultraviolet resistance, the color difference ΔE calculated using the initial reflection spectrum of the laminate 1 and the reflection spectrum after 24 hours of ultraviolet irradiation is preferably 3 or less, more preferably 2.5 or less, and even more preferably 2 or less. Use the initial reflectance spectrum and the reflectance spectrum after 24 hours of UV irradiation, and the relative spectral distribution of CIE standard illuminant D65 to calculate the CIE-L ^* a ^* b ^{* L *} value in the color system before and after UV irradiation , A ^* value and b ^* value, use these values to find the color difference ΔL ^* , Δa ^* and Δb ^* before and after UV irradiation, and use the color difference to find the color difference ΔE according to the following formula. ΔE={(ΔL ^* ) ² +(Δa ^* ) ² +(Δb ^* ) ² } ^0.5

In the laminated body of the embodiment of the present invention, the laminated body is bonded to a glass plate via the adhesive layer, and then visible light having a wavelength in the range of 380 nm to 780 nm is irradiated to the laminated body through the glass plate. Reflect spectrum, and keep the laminate bonded to the glass plate for 500 hours in an environment with a temperature of 65°C and a humidity of 90%, and then irradiate visible light with a wavelength in the range of 380 nm to 780 nm through the glass plate. The layered body is used to obtain the reflection spectrum, and the difference between the minimum wavelengths in the above two reflection spectra is preferably 15 nm or less. From the viewpoint of high temperature and humidity resistance, the minimum wavelength in the initial reflection spectrum of the laminate 1 (the wavelength at which the reflectance becomes the minimum value; hereinafter also referred to as the "bottom wavelength") and exposure to high temperature and high humidity environment The minimum wavelength difference in the reflection spectrum after 500 hours is preferably 15 nm or less, more preferably 10 nm or less, and still more preferably 5 nm or less.

＜Radio wave permeability＞ When the laminated body 1 is provided with the metal layer 12, it is preferable to make the metal layer 12 into a discontinuous structure as mentioned above in order to improve radio wave transmittance. The radio wave transmittance of the laminated body 1 can be evaluated based on, for example, the amount of radio wave transmission attenuation. 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), which shows a relatively close value. Therefore, the radio wave transmission in the microwave frequency band is relatively close. The laminated body (metallic luster film) with excellent performance has excellent radio wave permeability in the frequency band of millimeter wave radar. The radio wave transmission attenuation in the microwave band (5 GHz) of the laminate 1 of this embodiment 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 metal layer 12 (when the indium oxide-containing layer 11 is provided, it is the sheet resistance of the laminate of the indium oxide-containing layer 11 and the metal layer 12) is also related to the radio wave permeability. The sheet resistance of the metal layer 12 (when the indium oxide-containing layer 11 is provided, it is the sheet resistance of the laminate of the indium oxide-containing layer 11 and the metal layer 12) is preferably 100 Ω/□ or more. In this case, the microwave frequency band The transmission attenuation of (5 GHz) radio waves is about 10 to 0.01 [-dB]. The sheet resistance of the metal layer 12 (when the indium oxide-containing layer 11 is provided, it is the sheet resistance of the laminate of the indium oxide-containing layer 11 and the metal layer 12) is more preferably 200 Ω/□ or more, and more preferably 600 Ω/ □ or more, more preferably 1000 Ω/□ or more. The sheet resistance can be measured by the eddy current measurement method in accordance with JIS-Z2316-1:2014.

The attenuation of the electric wave and the sheet resistance are affected by the material or thickness of the metal layer 12. In addition, when the layered body 1 is provided with the indium oxide-containing layer 11, it is also affected by the material or thickness of the indium oxide-containing layer 11, and the like.

＜Difference between the maximum and minimum reflectivity＞ The difference between the maximum value and the minimum value of the reflectance of the surface on the side of the adhesive layer 15 of the laminate 1 in the wavelength range of 380 nm to 780 nm is preferably 30% or more. If the difference between the maximum and minimum reflectance is more than 30%, the appearance of the color can be darker. From the viewpoint of the depth of coloring, it is more preferably 35% or more, and still more preferably 40% or more. Furthermore, the upper limit of the difference between the maximum value and the minimum value of the reflectance is not particularly limited.

[Manufacturing of laminated body] The formation method in the case of forming the indium oxide-containing layer 11 on the base film 10 is not particularly limited, and examples thereof include a vacuum evaporation method, a sputtering method, an ion plating method, and the like. In order to strictly control the thickness even if the area is large, the sputtering method is preferred.

The method of forming the metal layer 12 when forming the metal layer 12 on the base film 10 (when the indium oxide-containing layer 11 is formed on the indium oxide-containing layer 11) is also not particularly limited. For example, a vacuum evaporation method, Sputtering method, etc.

The method for forming the optical adjustment layer 13 on the base film 10 (on the metal layer 12 when the metal layer 12 is formed) is also not particularly limited. Examples include: vacuum evaporation, sputtering, and ion plating. Method, coating method, etc.

The method of forming the barrier layer 14 on the optical adjustment layer 13 is also not particularly limited. For example, a vacuum evaporation method, a sputtering method, an ion plating method, a coating method, etc. may be mentioned.

The adhesive layer 15 can be formed by operations such as coating an adhesive composition on the barrier layer 14. The adhesive composition can be coated with a conventional coater, such as a gravure roll coater, a reverse roll coater, a touch roll coater, a dip roll coater, a bar coater, and a knife coater. Machine, spray coating machine, etc. The drying temperature is not particularly limited, but is preferably 40°C to 200°C, more preferably 50°C to 180°C, and particularly preferably 70°C to 120°C. The drying time is also not particularly limited, and is preferably 5 seconds to 20 minutes, more preferably 5 seconds to 10 minutes, and particularly preferably 10 seconds to 5 minutes.

[Use of laminated body] The laminated body 1 of the present embodiment is used by sticking, for example, on the surface of the inner side (the side opposite to the visible side) of a transparent adhered member. As a transparent member to be adhered, for example, a member including glass or plastic can be used, but it is not limited to this.

As the use of the member decorated with the laminate of the present embodiment, for example, there can be exemplified: automotive structural parts, automotive supplies, housings of electronic equipment, housings of home appliances, structural parts, mechanical parts, and various automotive parts , Electronic equipment parts, furniture, kitchen supplies and other household movable products, medical equipment, parts of construction materials, other structural parts or exterior parts, etc. More specifically, vehicle-related examples include: dashboards, console boxes, door handles, door trims, gear levers, pedals, glove boxes, bumpers, hoods, mudguards, luggage compartments, doors, sunroofs , Pillar, seat, steering wheel, ECU (electronic control unit, electronic control unit) box, electrical parts, engine peripheral parts, drive system/gear peripheral parts, intake/exhaust system parts, cooling system parts, etc. Examples of electronic equipment and home appliances include more specifically: 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), walkmans, handheld game consoles, chargers, batteries and other electronic information equipment. [Example]

Hereinafter, the present invention will be specifically described using examples, but the present invention is not limited in any way by these examples.

<Production of laminates of Examples 1 to 3 and Comparative Example 1> As a base film, a PET film (50 μm thick) manufactured by Mitsubishi Plastics Co., Ltd. was formed with a thermosetting resin having a thickness of 2000 μm formed on one side. First, install the ITO target on a DC (direct current, direct current) magnetron sputtering device, introduce Ar gas on one side, and sputter on the other side, thereby directly forming an indium oxide-containing layer with a thickness of 8 nm along the surface of the substrate film (ITO layer). 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 wt%.

Secondly, the aluminum (Al) target was installed in an AC sputtering device (AC (alternating current, AC): 40 kHz), and Ar gas was introduced on one side and sputtered on the other side, thereby forming a thickness of 30 nm on the ITO layer. Metal layer (Al layer). The obtained Al layer is a discontinuous layer. The temperature of the base film when forming the Al layer was set to 130°C. Furthermore, the method for measuring the thickness of the metal layer will be described below.

Secondly, the aluminum (Al) target was installed in an AC sputtering device (AC: 40 kHz), while introducing О ₂ gas, while sputtering was performed, thereby forming a barrier layer (AlO _{x) with a thickness of 10 nm on the Al layer.} Floor). The temperature of the base film when forming the AlO _x layer was set to 130°C.

Secondly, a Si target (AC: 40 kHz) was installed in an AC sputtering device, and O ₂ gas and N ₂ gas were introduced while sputtering was performed on the other side, thereby forming a 170 nm optical adjustment layer (SiN _{x) on the AlO x layer.} Floor). The temperature of the base film when forming the SiN _x layer is set to -8°C.

Next, a Si target (AC: 40 kHz) was installed in an AC sputtering device, and Ar gas and O ₂ gas were introduced while sputtering was performed on the other side, thereby forming a 20 nm barrier layer (SiO ₂ layer) _{on the SiN x layer} . The temperature of the base film when forming the SiO ₂ layer was set to -8°C.

Next, an adhesive layer (optical transparent adhesive sheet, thickness 25 μm, a product named "CS9861UAS" manufactured by Nitto Denko Co., Ltd.) was attached _{to the SiO 2 layer to obtain the laminate of Example 1.}

_{In addition, except that the thickness of the SiO 2} layer was changed as shown in Table 1, the laminates of Examples 2 and 3 were obtained in the same manner as Example 1. In addition, instead of forming an SiO ₂ layer, an adhesive layer was formed on the SiN _x layer. In the same manner as in Example 1, a laminate of Comparative Example 1 was obtained except that an adhesive layer was formed on the SiN x layer.

＜Measuring method of thickness of metal layer＞ First, as shown in Figure 2, a square area 3 with a side length of 5 cm is appropriately selected from the laminate, and the center lines A and B of the vertical and horizontal sides of the square area 3 are divided into four equal parts. A total of 5 points "a" to "e" are obtained, and these 5 points are selected as the measurement site. Then, the cross-sectional images (transmission electron micrographs (TEM images)) of the selected measurement sites are measured, and the viewing angle regions containing more than 5 metal particles are selected from the obtained TEM images. Divide the total cross-sectional area of the metal layer in the viewing angle area selected for the 5 measurement locations by the width of the viewing area, and set the value as the thickness of the metal layer in each viewing area, and select the 5 measurement locations. The average value of the film thickness of the metal layer in each viewing angle area is taken as the thickness (nm) of the metal layer.

＜Measurement of sheet resistance＞ For the laminates of Examples 1 to 3 and Comparative Example 1, the non-contact resistance measuring device NC-80MAP manufactured by Napson Company was used in accordance with JIS-Z2316, and the eddy current measurement method was used to measure the difference between the metal layer and the indium oxide-containing layer. The sheet resistance of the laminate was measured, and the results were all 1 kΩ or more.

＜Evaluation of durability of temperature and humidity＞ The laminates of Examples 1 to 3 and Comparative Example 1 were bonded to a glass plate via an adhesive layer. After that, it was placed in a high-temperature and high-humidity environment with a temperature of 65°C and a humidity of 90% for 500 hours. Before being placed in a high temperature and high humidity environment, at a time point after 240 hours in a high temperature and high humidity environment, and at a time point after 500 hours, the spectral reflectance was measured as described below. When measuring the spectral reflectance, use a spectrophotometer to irradiate visible light with a wavelength of 380 nm to 780 nm to the laminate through a glass plate at 5 nm intervals to measure the spectral reflectance of the reflected light.

In this way, the reflection spectrum of the wavelength range from 380 nm to 780 nm was obtained, and the minimum wavelength (bottom wavelength) and the maximum wavelength (peak wavelength) are shown in Table 1.

Also, use the reflectance spectrum of the wavelength range of 380 nm ~ 780 nm obtained in this way and the relative spectral distribution of the CIE standard light source D65 to calculate the L ^* value and a ^* value ^{in the CIE-L *} a ^* b ^{* color system} And b ^* value. Using these calculated values, find the time point before the high temperature and high humidity environment (initial value), the time point after 240 hours in the high temperature and high humidity environment (after 240 h), and the time point after 500 hours (elapsed). After 500 h), the color difference ΔL ^* , Δa ^*, and Δb ^{* are} calculated using the following formula. The results are shown in Table 1. ΔE={(ΔL ^* ) ² +(Δa ^* ) ² +(Δb ^* ) ² } ^0.5

[Table 1] SiO ₂ layer thickness [nm] Evaluation of durability of temperature and humidity Bottom wavelength [nm] Peak wavelength [nm] ∆E Initial value After 240 h After 500 h Initial value After 240 h After 500 h After 240 h After 500 h Comparative example 1 0 420 420 400 580 580 580 1.4 2.0 Example 1 20 420 420 420 580 580 580 1.0 1.3 Example 2 40 420 420 420 580 580 580 1.2 1.5 Example 3 50 420 420 420 580 580 580 1.2 1.6

In Comparative Example 1, after being placed in a high temperature and high humidity environment for 500 hours, the bottom wavelength of the reflection spectrum shifted to the short wavelength side of 20 nm. On the other hand, in Examples 1 to 3, even after being placed in a high temperature and high humidity environment for 500 hours, the bottom wavelength and peak wavelength of the reflection spectrum did not shift, and the high temperature and high humidity durability was excellent.

<Production of laminates of Examples 4-7 and Comparative Example 2> An example was produced in the same manner as in Example 1, except that _{a 150 nm Nb 2} O ₅ layer was formed instead of the SiN _{x layer as the optical adjustment layer} 4 of the layered body. In addition, _{the formation of the Nb 2} O ₅ layer was performed by mounting a Nb target (AC: 40 kHz) in an AC sputtering device, introducing Ar gas and O ₂ gas, and performing sputtering. The temperature of the base film when forming the Nb ₂ O ₅ layer was set to -8°C. _{In addition, except that the thickness of the SiO 2} layer was changed as shown in Table 2, the laminates of Examples 5 and 6 were obtained in the same manner as Example 4. _{In addition, a 50 μm SiO 2} layer was further formed between the AlO _x layer and the Nb ₂ O ₅ layer. In the same manner as in Example 5, a laminate of Example 7 was obtained. The 50/50 in the column of "SiO ₂ layer thickness" in Table 2 means that the thickness of both _{SiO 2 layers is 50 μm.} In addition, _{instead of forming an SiO 2} layer, an adhesive layer was formed on the Nb ₂ O ₅ layer. In the same manner as in Example 4, except that an adhesive layer was formed, a laminate of Comparative Example 2 was obtained.

＜Measurement of sheet resistance＞ Regarding the laminates of Examples 4 to 7 and Comparative Example 2, the sheet resistance was measured in the same manner as in Examples 1 to 3 and Comparative Example 1, and the results were all 1 kΩ or more.

＜Evaluation of durability of ultraviolet light＞ The laminates of Examples 4 to 7 and Comparative Example 2 were bonded to a glass plate via an adhesive layer. After that, it was put into a UV tester, and the laminate was irradiated with ultraviolet light through the glass plate, and the laminate was kept for 500 hours. Before putting into the UV tester, 24 hours after putting into the UV tester, 240 hours, and 500 hours, the same as in Examples 1 to 3 and Comparative Example 1, respectively The spectral reflectance is measured, and the minimum wavelength (bottom wavelength) and maximum wavelength (peak wavelength), and ΔE are determined. Table 2 shows the maximum and minimum wavelengths at the time of 240 hours before the UV tester, the 240 hours after the UV tester, and the 500 hours after the UV tester, and the 24 hours after the UV tester. ΔE at the time point.

[Table 2] SiO ₂ layer thickness [nm] Evaluation of the durability of ultraviolet light Bottom wavelength [nm] Peak wavelength [nm] ∆E Initial value After 240 h After 500 h Initial value After 240 h After 500 h After 24 h Comparative example 2 0 360 360 360 420 420 420 3.6 Example 4 20 360 360 360 430 430 430 1.4 Example 5 50 360 360 360 420 420 420 2.1 Example 6 80 360 360 360 420 420 420 2.1 Example 7 50/50 380 380 380 470 470 470 1.7

In Comparative Example 2, the ΔE is greater after 24 hours of exposure to ultraviolet light. On the other hand, in Examples 4-7, even after 24 hours of ultraviolet light irradiation, ΔE was small, and ultraviolet light durability was excellent. [Industrial availability]

According to the present invention, it is possible to provide a laminated body that can decorate the adhered member to give it a colored appearance, thereby suppressing changes in appearance caused by various factors such as ultraviolet rays, temperature, and humidity.

The present invention has been described in detail with reference to specific embodiments, but those skilled in the art should know that various changes or modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Japanese Patent Application 2019-179322) filed on September 30, 2019, and the content is incorporated herein by reference.

1: Layered body 3: square area 10: Substrate film 11: Indium oxide layer 12: Metal layer 12a: part 12b: gap 13: Optical adjustment layer 14: barrier layer 15: Adhesive layer A, B: center line a～e: point

Fig. 1 is a schematic cross-sectional view of a laminate according to an embodiment of the present invention. Fig. 2 is a diagram for explaining a method of measuring the film thickness of a metal layer of a laminate according to an embodiment of the present invention.

1: Layered body

10: Substrate film

11: Indium oxide layer

12: Metal layer

12a: part

12b: gap

13: Optical adjustment layer

14: barrier layer

15: Adhesive layer

Claims (8)

A laminated body which is provided with a substrate film, an optical adjustment layer, a barrier layer and an adhesive layer in this order, and The optical adjustment layer contains at least one selected from the group consisting of metal oxides, metal nitrides, and metal sulfides, and has a refractive index of 1.75 or more. The barrier layer is a layer containing metal oxide and/or metal nitride, The above-mentioned adhesive layer is a layer containing a transparent adhesive. The laminate of claim 1, wherein a metal layer is further provided between the base film and the optical adjustment layer. Such as the laminated body of claim 2, wherein the metal layer includes at least a plurality of parts in a mutually discontinuous state. The laminate of claim 2 or 3, wherein an indium oxide-containing layer is further provided between the base film and the metal layer. The laminate according to any one of claims 1 to 4, wherein the optical adjustment layer contains Si and/or Nb. The laminate according to any one of claims 1 to 5, wherein the barrier layer contains SiO ₂ . The laminated body according to any one of claims 1 to 6, wherein the laminated body is bonded to a glass plate via the adhesive layer, and then visible light with a wavelength in the range of 380 nm to 780 nm is irradiated through the glass plate The reflection spectrum obtained by the laminated body is irradiated with ultraviolet light through the glass plate to the laminated body bonded to the glass plate for 24 hours, and then visible light with a wavelength in the range of 380 nm to 780 nm is irradiated through the glass plate. The reflection spectrum obtained by irradiating the glass plate to the above-mentioned laminate has a calculated color difference ΔE of 3 or less. The laminated body according to any one of claims 1 to 7, wherein the laminated body is bonded to a glass plate via the adhesive layer, and then visible light with a wavelength in the range of 380 nm to 780 nm is irradiated to the glass plate through the glass plate The minimum wavelength of the reflection spectrum obtained by the above-mentioned laminated body and the above-mentioned laminated body bonded to the above glass plate are kept in an environment with a temperature of 65°C and a humidity of 90% for 500 hours, and the wavelength is in the range of 380 nm to 780 nm. The minimum wavelength of the reflection spectrum obtained by irradiating visible light to the laminate through the glass plate, the difference is 15 nm or less.

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