JP7613469B2 - Frequency selective surface loading member and vehicle window member - Google Patents

Description

The present invention relates to a frequency selective surface loading member and a window member for a vehicle.

In recent years, with the increase in communication speed and capacity, the frequency band of radio waves used for communication has expanded to higher frequency bands. For example, the recent fourth generation mobile communication systems (hereinafter referred to as "4G") and fifth generation mobile communication systems (hereinafter referred to as "5G") use radio waves in the frequency band of several hundred MHz to several tens of GHz.

To communicate in such high frequency bands, for example, it has been proposed to mount a radar device on the exterior of a vehicle, such as in an emblem or in the front grill. In recent years, moreover, by mounting a radar device inside the vehicle, particularly on the inside of the windshield, it has become possible to communicate efficiently from a position relatively higher above the ground than in an emblem or in the front grill.

However, laminated glass used in windshields has the problem of reducing radio wave transmittance due to reflection and absorption when radio waves pass through. In addition, radio wave transmittance also varies depending on the angle of the windshield and the thickness of the glass. Furthermore, a heat ray reflective film is used in windshields to reduce the cooling load, but in this case, there is also the problem that the conductive film contained in the heat ray reflective film blocks radio waves.

The above problem can occur not only in laminated glass for vehicles, but also in Low-E insulating glass used in window panes in buildings, etc. With the use of high-frequency bands for communications, there is a demand to improve radio wave transparency while maintaining good thermal performance.

To address the above problem, for example, Patent Document 1 proposes a communications window having an enhanced frequency selective surface with arcuate breaks, which is designed to allow selected radio frequencies to pass through unattenuated.

Furthermore, Patent Document 2 proposes a dielectric substrate having multiple convex-shaped dielectric portions arranged periodically on one surface, improving the transmission characteristics of radar waves incident on the dielectric surface.

International Publication No. 2004/093497 International Publication No. 2019/180926

In the communication window described in Patent Document 1, the radio wave transmission is insufficient when the radio waves are incident at an angle, and there is room for improvement. In addition, the dielectric substrate described in Patent Document 2 has a problem in that the aesthetic appearance and visibility are poor due to the arrangement of multiple convex dielectric parts.

The present invention provides a frequency selective surface loading component and a vehicle window component that can improve radio wave transmittance without compromising thermal performance or processability.

The frequency selective surface loading member of the present invention has a laminated member having a total of n dielectric layers stacked in order from a first layer to an nth layer (where n is an integer of 3 or more), and at least one of the main surfaces of the dielectric layers constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F, and the frequency selective surface has a conductive portion and a non-conductive portion, and has a solar transmittance of 54% or less as specified in ISO 9050:2003.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the laminated member may have two continuous intermediate bodies other than the outermost dielectric layer of the laminated member as a dielectric layer, and the frequency selective surface may be provided between the two continuous intermediate bodies.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the two consecutive intermediate bodies may be made of the same resin material.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the resin material may be PVB or EVA.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the first layer and the nth layer may be glass substrates.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the first layer or the nth layer may be a shielding layer that blocks visible light, and in a planar view of the laminated member, at least a portion of the frequency selective surface may overlap with the shielding layer.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the dielectric layer adjacent to the shielding layer may be a glass substrate.

Furthermore, in a frequency selective surface loading member according to one embodiment of the present invention, the distance from the frequency selective surface to the surface of the first layer opposite the second layer and the distance from the frequency selective surface to the surface of the nth layer opposite the n-1th layer may be approximately the same.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the laminated member may be composed of four dielectric layers, with a first glass substrate, a first resin layer, a second resin layer, and a second glass substrate being laminated in that order from the first layer.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the laminated member may be composed of five dielectric layers, in which a first glass substrate, a first resin layer, a third resin layer, a second resin layer, and a second glass substrate are laminated in this order from the first layer.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the frequency selective surface may be provided on at least one of the two outermost surfaces of the laminated member.

In addition, in a frequency selective surface loading member according to one aspect of the present invention, the visible light transmittance as specified in ISO 9050:2003 may be 60% or more.

In addition, in one embodiment of the frequency selective surface loading member of the present invention, the solar reflectance specified in ISO 9050:2003 may be 8% or more.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the visible light reflectance as specified in ISO 9050:2003 may be 15% or less.

In the frequency selective surface loading member according to an aspect of the present invention, the visible light reflection color tone Rva ^* defined in ISO 9050:2003 may be −10 to 5, and the visible light reflection color tone Rvb ^* may be −10 to 10.

In the frequency selective surface loading member according to an aspect of the present invention, the visible light transmission color tone, Ta ^*, as defined in ISO 9050:2003, may be −8 to 5, and Tb ^* may be −8 to 6.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the width G of the non-conductive portion of the frequency selective surface may be 0.01 mm to 0.5 mm.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the sheet resistance of the conductive portion of the frequency selective surface may be 50 Ω/□ or less.

In addition, in a frequency selective surface loading member according to one embodiment of the present invention, the conductive portion of the frequency selective surface may include at least one selected from the group consisting of Ag, ITO, tin oxide doped with at least one of fluorine and antimony, and Cu.

Furthermore, in a frequency selective surface loading member according to one embodiment of the present invention, when the frequency selective surface loading member is used as a window member, the non-conductive portion of the frequency selective surface may have at least one of a horizontal component and a vertical component relative to the ground.

In addition, a frequency selective surface loading member according to one embodiment of the present invention may have, in a planar view, a first region having the frequency selective surface and a second region not having the frequency selective surface.

In addition, in one embodiment of the frequency selective surface loading member of the present invention, when viewed in a plan view, the outer edge of the first region may be located inside the outer edge of the second region.

Furthermore, in a frequency selective surface loading member according to one embodiment of the present invention, the frequency F may be included in the range of 1 GHz to 100 GHz.

The vehicle window member of the present invention is equipped with the above-mentioned frequency selective surface loading member.

A vehicle window member according to one aspect of the present invention may be a windshield for a vehicle.

The frequency selective surface loading member of the present invention can improve radio wave transparency without compromising thermal performance or processability.

FIG. 1 is a cross-sectional view showing an outline of the structure of an FSS loading member according to this embodiment. FIG. 2 is a plan view of an example of an FSS loading member according to this embodiment, showing a first region A having an FSS and a second region B not having an FSS. 3A and 3B are diagrams showing examples of the shape (plan view) of the FSS in this embodiment. Fig. 3A shows a shape in which the non-conductive parts are formed in a double lattice pattern in plan view. Fig. 3B shows a circular loop slot type in which multiple ring-shaped non-conductive parts are formed in plan view. FIG. 4 is a cross-sectional view of an FSS loading member according to one embodiment of the present invention. FIG. 5 is a cross-sectional view of an FSS loading member according to another embodiment of the present invention. FIG. 6 is a cross-sectional view of the FSS loading member of Example 1. FIG. 7 is a cross-sectional view of the FSS loading member of Example 2.

Below, an embodiment of the present invention will be described in detail. In addition, in the following drawings, components and parts that perform the same function may be described with the same reference numerals, and duplicated descriptions may be omitted or simplified. In addition, the embodiments shown in the drawings are schematic in order to clearly explain the present invention, and do not necessarily accurately represent the size or scale of the actual product.

In this embodiment, the term "laminate member" refers to a laminate in which multiple dielectric layers are stacked, and is a configuration that does not include a frequency selective surface. On the other hand, a "frequency selective surface loading member" is a configuration in which a frequency selective surface is loaded onto at least one of the main surfaces of multiple dielectric layers that make up the laminate member. Thus, in this specification, "laminate member" and "frequency selective surface loading member" are distinguished as configurations that include a frequency selective surface and configurations that do not include a frequency selective surface.

The frequency selective surface loading member (hereinafter also referred to as FSS loading member) according to this embodiment has a laminated member having a total of n dielectric layers stacked in order from the first layer to the nth layer (where n is an integer of 3 or more). At least one of the main surfaces of the multiple dielectric layers constituting the laminated member is provided with a frequency selective surface (hereinafter also referred to as FSS) that transmits radio waves of a predetermined frequency F. The FSS has a conductive part and a non-conductive part, and is characterized in that the solar transmittance specified in ISO9050:2003 is 54% or less.

In this way, the FSS-loaded member of this embodiment is a laminated member having multiple dielectric layers, to which an FSS that transmits radio waves of a predetermined frequency F is loaded, and by keeping the solar transmittance low, it is possible to improve radio wave transmittance without compromising thermal performance.

Figure 1 is a cross-sectional view showing the structure of the FSS loading member according to this embodiment. As shown in Figure 1, the FSS loading member 10 has a laminated member having a total of n dielectric layers stacked in order from the first layer to the nth layer. In other words, such a laminated member is configured such that the dielectric layer located on one of the outermost surfaces is the first layer, and the second layer to the nth layer are stacked in order on the main surface side opposite the outermost surface of the laminated member out of the two main surfaces of the first layer. In addition, the laminated member in the FSS loading member 10 is composed of three or more dielectric layers. In other words, n is an integer of 3 or more.

In the FSS-loaded member of this embodiment, an FSS that transmits radio waves of a predetermined frequency F is provided on at least one of the main surfaces of the multiple dielectric layers that make up the laminated member. Such an FSS has the function of selectively transmitting radio waves of a preset frequency F and suppressing the transmission of radio waves of frequencies other than that frequency band. By providing an FSS that transmits radio waves of a predetermined frequency F at a predetermined position in this way, the FSS-loaded member of this embodiment is able to increase radio wave transparency.

Here, "in the FSS-loaded member of this embodiment, an FSS is provided on at least one of the main surfaces of the multiple dielectric layers constituting the laminate member" means that an FSS is provided on at least one of the main surfaces of all the dielectric layers constituting such laminate member.

For example, if the laminated member has a total of three dielectric layers (n=3), the laminated member has four main surfaces: the outermost surface on the first layer side, the main surface between the first and second layers, the main surface between the second and third layers, and the outermost surface on the third layer side. Note that if the main surfaces overlap, the number of main surfaces is counted as one. Therefore, in this case, the FSS loading member has an FSS provided on at least one of the four main surfaces of the laminated member.

The FSS loading member according to this embodiment has a solar transmittance of 54% or less as specified by ISO 9050:2003. This provides a good heat shielding effect and excellent thermal properties. The solar transmittance of the FSS loading member according to this embodiment is preferably 54% or less, more preferably 50% or less, even more preferably 45% or less, particularly preferably 41% or less, and most preferably 38% or less.

The solar radiation transmittance of the FSS-loaded member of this embodiment is kept low as described above because the conductive portion forming the FSS has a solar radiation reflection function. The solar radiation reflection function is proportional to the area of the conductive portion. If the FSS is not designed appropriately, a large portion of the conductive portion must be removed as a radio wave transparent member, and it is not possible to achieve both solar radiation reflectivity and radio wave transparency. However, by appropriately designing the FSS, it is possible to improve radio wave transparency while maintaining a high residual rate of the conductive portion, making it possible to achieve both solar radiation reflectivity and radio wave transparency.

In addition, the FSS loading member according to this embodiment preferably has a visible light transmittance of 60% or more as specified in ISO 9050:2003. This provides excellent visibility for the FSS loading member. In addition, the visible light transmittance of the FSS loading member according to this embodiment is preferably 65% or more, and more preferably 70% or more.

The visible light transmittance of the FSS loading member in this embodiment can be made as high as described above because a transparent conductive film such as Ag or ITO is used in the conductive portion that constitutes the FSS.

In addition, the solar reflectance of the FSS loading member according to this embodiment, as defined by ISO 9050:2003, is preferably 8% or more, and more preferably 12% or more. By having the solar reflectance in the above range, a good heat shielding effect is obtained, and the thermal properties are excellent.

In addition, the visible light reflectance of the FSS loading member according to this embodiment, as defined by ISO 9050:2003, is preferably 15% or less, and more preferably 10% or less. When the visible light reflectance is in the above range, the visibility of the FSS loading member is excellent.

The visible light reflection color tone Rva ^* of the FSS loading member according to this embodiment, as defined by ISO 9050:2003, is preferably −10 to 5, and Rvb ^* is preferably −10 to 10. When Rva ^* and Rvb ^* are within the above ranges, the color difference with the non-conductive portion becomes small, making the FSS pattern less visible, and the aesthetic appearance of the FSS loading member is excellent.

In addition, the Ta ^* of the visible light transmission color tone of the FSS loading member according to this embodiment, as defined by ISO9050:2003, is preferably −8 to 5, and Tb ^* is preferably −8 to 6. When Ta ^* and Tb ^* are within the above ranges, the color difference with the non-conductive part is small and the FSS pattern is difficult to see, so that the aesthetic appearance of the FSS loading member is excellent.

In this embodiment, the FSS loading member 10 may be provided such that, in a plan view, the outer edge of the FSS is located inside the outer edge of the FSS loading member 10. In other words, the FSS loading member 10 may be provided with a specific region that improves the transparency of radio waves of frequency F.

Note that the plan view corresponds to a view from the normal direction of the main surface of the FSS loading member 10. For example, FIG. 2 illustrates a case where the FSS loading member 10 is a vehicle window member, but the FSS loading member 10 according to this embodiment may have a first region A having an FSS in a plan view and a second region B having no FSS.

Note that, although the FSS loading member 10 shown in Figure 2 shows a case in which the outer edge of the first region A is located inside the outer edge of the second region B, when viewed in a plan view of the FSS loading member 10, a portion of the outer edge of the first region A may share or overlap a portion of the outer edge of the second region B.

Alternatively, the FSS loading member according to this embodiment may be provided so that the outer edge of the FSS is approximately aligned with the outer edge of the laminated member in a plan view. That is, the FSS loading member according to this embodiment may have an FSS and other dielectric layers of approximately the same size.

In addition, when the FSS loading member 10 in this embodiment is a vehicle windshield, the first region A may be provided in a position that does not obstruct the driver's view in a plan view, such as near the upper center of the FSS loading member (Figure 2) or at the lower part.

Here, if the vertical length of the vehicle's windshield is "D", for example, the "upper part" can be an example of the area extending downward from the top edge of the windshield by a distance of 0.3 x D or less, and the "lower part" can be an example of the area extending upward from the bottom edge of the windshield by a distance of 0.3 x D or less.

In addition, the "upper part" may be the area up to a distance of 0.2 x D or less from the upper edge of the windshield, and the "lower part" may be the area up to a distance of 0.2 x D or less from the lower edge of the windshield.

Furthermore, when the FSS loading member 10 according to the present embodiment is a windshield for a vehicle, the FSS loading member 10 may be provided on the entire surface of the windshield, not just on a part of the windshield, as long as the driver's visibility is adequately maintained. At the very least, the FSS loading member should be provided in an area that ensures transmission and reception of radio waves of a predetermined frequency F.

In addition, when the FSS loading member 10 of this embodiment is used as a window member for a vehicle, it may be used not only for windshields, but also for rear glass, side glass, rear quarter glass, roof glass, plastic doors, plastic roofs, rear spoilers, and other plastic aero parts.

Below, each component of the FSS loading member in this embodiment is described in further detail.

<Dielectric Layer>
The dielectric layer is a material in which dielectricity is superior to electrical conductivity, and when an external electric field is applied, the dielectric layer is electrically polarized. The type of dielectric layer included in the FSS loading member is not particularly limited, and examples thereof include a dielectric substrate such as a glass substrate or a resin substrate, an intermediate body provided between dielectric substrates, a coating layer, a coating layer provided on the surface of the dielectric substrate (the outermost surface side of the FSS loading member), and air. When the dielectric layer is air, the air is limited to any one of the second layer to the n-1th layer, and can be used as a dielectric layer between dielectric substrates, particularly a dielectric layer between glass substrates.

As the glass substrate, for example, soda lime glass, alkali-free glass, borosilicate glass, quartz glass, etc. can be used. As the glass substrate, a tempered glass substrate that has been subjected to a physical tempering treatment or a chemical tempering treatment may be used. As the glass substrate, float glass produced by the float method is preferable. As the glass substrate, glass produced by the fusion method may be used.

Examples of resin substrates include substrates made of acrylic resins such as polymethyl methacrylate, aromatic polycarbonate resins such as polyphenylene carbonate, and aromatic polyester resins such as polyethylene terephthalate (PET).

As an intermediate body provided between dielectric substrates, for example between glass substrates, a resin layer containing a resin material such as polyvinyl butyral (PVB), ethylene vinyl acetal (EVA), polyethylene terephthalate (PET) or the like can be used.

The intermediate body may be a thermosetting resin that is liquid before heating. In other words, the intermediate body may be in a layered form when it is in the form of a laminated member, and may be liquid before bonding to a dielectric substrate or the like.

Furthermore, the intermediate may be air (vacuum) as exemplified above, or may contain at least one selected from PVB, EVA, and air. And the non-conductive portion of the FSS may contain at least one selected from PVB, EVA, and air.

In the FSS loading member according to this embodiment, the intermediate body may have multiple layers. In this specification, when there are a total of m layers of intermediate bodies, they are referred to as the first intermediate body, the second intermediate body, ..., the mth intermediate body, where m is an integer between 1 and n-2.

Examples of the coating layer include functional coating layers having various functions, such as light shielding layers such as black ceramic layers, coating layers that impart water repellency, hydrophilicity, and anti-fogging functions, and heat ray reflection layers. These coating layers include layers that are thinner than the dielectric substrate, and layers made of materials that are less rigid than the dielectric substrate. Coating layers are often arranged so as to coat the main surface of a dielectric substrate made of a rigid glass substrate having a predetermined thickness.

The coating layer can be formed by a physical vapor deposition method such as sputtering, vacuum deposition, or ion plating. The coating layer may also be formed by a chemical vapor deposition method or a wet coating method.

In the FSS loading member according to the present embodiment, a dielectric substrate is usually used for the outermost dielectric layer (at least one of the first layer and the nth layer). In particular, when the FSS loading member according to the present embodiment is used as a laminated glass for a vehicle, it is preferable to use a glass substrate for the first layer and the nth layer.

However, when a coating layer such as a black ceramic layer is provided on the second layer or the (n-1)th layer as the first layer or the nth layer of the FSS loading member according to this embodiment, it may become a coating layer. Note that a coating layer such as a black ceramic layer is a layer that blocks visible light, and is also called a shielding layer.

In this way, using a shielding layer as the outermost layer of the dielectric layer of the FSS-loaded member can improve the design, especially when used as laminated glass for vehicles. In addition, when the FSS-loaded member is laminated glass for vehicles, it is preferable that the FSS overlaps at least a part of the shielding layer in a plan view, making the FSS less visible, and it is even more preferable that the FSS overlaps the entire shielding layer.

When the outermost layer (first layer or nth layer) of the dielectric layers is a shielding layer, the dielectric layer adjacent to the shielding layer (second layer or n-1th layer) is preferably a glass substrate. The intermediate is used for any of the dielectric layers other than the outermost layer (other than the first layer and nth layer), i.e., any of the second layer to n-1th layer.

The shape of the dielectric layer is not particularly limited and may be planar or curved, with the main surface curved with a finite radius of curvature.

The dielectric constant of the dielectric layer is preferably 1 or more, more preferably 2.3 or more. The dielectric constant of the dielectric layer is preferably 7.2 or less, more preferably 7.0 or less, and even more preferably 6.8 or less. The dielectric constant of the dielectric layer is a value determined at 1 MHz using a dielectric breakdown test device in a test environment maintained at a temperature within a range of 23°C ± 2°C and a relative humidity within a range of 50% ± 5% RH according to the transformer bridge method in accordance with ASTM D150.

The dielectric constant of the first layer and the nth layer of the dielectric layer is preferably 2.3 or more. The dielectric constant of the first layer and the nth layer of the dielectric layer is preferably 7.2 or less, more preferably 7.0 or less, and even more preferably 6.8 or less.

In particular, it is preferable that at least one of the first to nth dielectric layers of the FSS loading member according to this embodiment has a dielectric constant close to that of the adjacent dielectric layer. This reduces reflection at the interface between the dielectric layers, improving radio wave transparency.

At least one of the dielectric layers in the FSS loading member may be a glass substrate. The composition of the glass substrate is not particularly limited. For example, when soda-lime glass is used as the glass substrate, the composition is expressed as the mole percentage of each component based on the oxide.
50%≦ _SiO2 ≦80%
0.1%≦ _{Al2O3 ≦} 25%
3%≦R ₂ O ≦30% (R ₂ O represents the total amount of Li ₂ O, Na ₂ O, and K ₂ O)
0%≦ _B2O3 ≦ ₁₀ %
0%≦MgO≦25%
0%≦CaO≦25%
0%≦SrO≦5%
0%≦BaO≦5%
0%≦ _ZrO2 ≦5%
0%≦ _SnO2 ≦5%
Examples of the materials that satisfy the above conditions include:

In addition, when non-alkali glass is used as the glass substrate for the FSS loading member, the content of each component expressed as a mole percentage based on the oxide is:
50%≦ _SiO2 ≦80%
0%≦ _{Al2O3 ≦} 30%
0%≦ _B2O3 ≦ ₂₅ %
0%≦MgO≦25%
0%≦CaO≦25%
0%≦SrO≦25%
0%≦BaO≦25%
0%≦ _ZrO2 ≦5%
5%≦RO≦40% (RO represents the total amount of MgO, CaO, SrO, and BaO)
Examples of the materials that satisfy the above conditions include:

Furthermore, the glass substrate may be made of borosilicate glass, which is an oxide-based glass containing silicon dioxide as a main component and boron as a component. The boron component in borosilicate glass is boron oxide (a general term for boron oxides such as diboron trioxide (B ₂ O ₃ )), and the proportion of boron oxide in the glass is expressed in terms of B ₂ O ₃ . Similarly, the main components in the glass are expressed as oxides such as SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , MgO, CaO, SrO, BaO, LiO ₂ , Na ₂ O, and K ₂ O, and the proportions are expressed on an oxide basis.

In the present embodiment, borosilicate glass refers to oxide-based glass containing 1.0% or more B ₂ O ₃ in terms of mole percentage based on oxide, and containing silicon dioxide as a main component.

The specific gravity of the glass substrate is preferably 2.4 or more and 3.0 or less. The Young's modulus of the glass substrate is preferably 60 GPa or more and 100 GPa or less.

The average thermal expansion coefficient of the glass substrate from 50° C. to 350° C. is preferably 50×10 ⁻⁷ /° C. or more. Also, the average thermal expansion coefficient of the glass substrate from 50° C. to 350° C. is preferably 120×10 ⁻⁷ /° C. or less. If the glass substrate satisfies these physical property requirements, it can be used sufficiently suitably as, for example, a window material.

<Frequency Selective Surface>
A frequency selective surface (FSS) has conductive and non-conductive parts in a plan view, and transmits radio waves of a predetermined frequency F while blocking the transmission of radio waves of frequencies other than that frequency band.

Here, the conductive portion of the FSS refers to the portion of the FSS whose sheet resistance at 20°C is 50 Ω/□ or less. The non-conductive portion of the FSS refers to the portion whose sheet resistance at 20°C is more than 50 Ω/□.

In addition, in the FSS, the difference in sheet resistance between the conductive and non-conductive parts at 20°C may be 50 Ω/□ or more, preferably 100 Ω/□ or more, and more preferably 1000 Ω/□ or more.

The material constituting the conductive portion of the FSS is not particularly limited, but examples include materials containing metals such as Ag, indium tin oxide (ITO), Cu, Al, tin oxide doped with at least one of fluorine and antimony ( _SnO2 :F,Sb), titanium nitride, niobium nitride, chromium nitride, zirconium nitride, and hafnium nitride.

Among them, it is preferable to include at least one selected from the group consisting of Ag, ITO, tin oxide doped with at least one of fluorine and antimony ( _SnO2 :F,Sb), and Cu. Note that the non-conductive portion may be, for example, a dielectric material constituting the dielectric layer, or air.

In this embodiment, the sheet resistance of the conductive portion of the FSS is preferably 50 Ω/□ or less, more preferably 30 Ω/□ or less, and even more preferably 10 Ω/□ or less. When the sheet resistance of the conductive portion is in the above range, the conductive portion and non-conductive portion of the FSS function effectively as an inductor or capacitor, improving radio wave transparency.

The sheet resistance of the conductive part of the FSS can be measured, for example, using a non-contact eddy current resistance measuring device, 717 conductance monitor, manufactured by DELCOM.

When the FSS loading member according to this embodiment is used as a window member, it is preferable that the non-conductive portion of the FSS has at least one of a horizontal component and a vertical component with respect to the ground. This is because, when used as a window member such as a window member for a vehicle, a part of the non-conductive portion is horizontal with the ground, resulting in good radio wave transmission for vertically polarized waves. Also, a part of the non-conductive portion is perpendicular to the ground, resulting in good radio wave transmission for horizontally polarized waves.

In addition, the shape of the FSS in plan view is not particularly limited. As a specific example, the shape of the FSS in this embodiment in plan view (XY plane) is described below in (A) and (B) of Figure 3, but the shape of the FSS is not limited to these.

First, the FSS 30a shown in FIG. 3A has a conductive portion 31a and a non-conductive portion 32a, and the non-conductive portion 32a is formed in a double lattice pattern when viewed in a plane.

Here, the double lattice pattern refers to a pattern in which multiple double vertical lines and multiple double horizontal lines are perpendicular to each other. In other words, the double lattice pattern refers to a shape in which the non-conductive portion 32a is formed into a double lattice pattern consisting of lines along the X-axis direction and the Y-axis direction perpendicular to the X-axis, with respect to the conductive portion 31a.

In such a shape, a repeating unit A is formed by multiple dimensional parameters, which has the advantage of allowing high design freedom. The FSS 30a shown in Fig. 3A is formed by a pattern in which a rectangular unit A (basic pattern) consisting of conductive parts 31a and non-conductive parts 32a is regularly and closely spaced in two dimensions in the X-axis and Y-axis directions.

In the FSS 30a shown in Fig. 3A, one quadrangular unit A may be a square with sides of equal length, or a rectangle with two sides of different lengths. In addition, the length L1 of one side of the quadrangular conductive portion 31a formed between adjacent double lattices in the Y-axis direction (the shortest distance between adjacent double lattices in the Y-axis direction), the length L2 of the conductive portion 31a formed within the double lattice, and the width G of the non-conductive portion 32a forming the double lattice stripes can be set appropriately.

L1 and L2 are preferably 0.05 mm to 5 mm, and width G is preferably 0.01 mm to 0.5 mm. Note that in FIG. 3A, the length L1, length L2, and width G of the FSS are all shown as lengths or widths in the Y-axis direction, but the above dimensions in the X-axis direction may also be within the above preferred numerical ranges.

In addition, the loading area of the FSS 30a in the FSS loading member can be set as appropriate, but when the wavelength in air corresponding to the frequency F of the transmitted radio wave is λ (mm), it is preferably ^λ2 mm2 or ^more , more preferably ^2λ2 mm2 or ^more , and even more preferably ^3λ2 mm2 or ^more .

The width G of the non-conductive portion 32a is preferably 250 μm or less, and more preferably 200 μm or less. The width G of the non-conductive portion 32a is preferably 10 μm to 250 μm, and more preferably 10 μm to 200 μm. When the width G of the non-conductive portion 32a is within the above range, the electric field is concentrated in the non-conductive portion 32a, which effectively acts as a capacitance, improving radio wave transparency.

In addition, when the FSS loading member according to this embodiment is used as a window member, it is preferable that the non-conductive portion of the FSS has at least one component horizontal and/or vertical to the ground. Here, the component horizontal to the ground corresponds to the multiple double horizontal lines in the FSS shown in FIG. 3A when the FSS is installed on a vehicle windshield in the orientation shown in FIG. 3A. In addition, the component vertical to the ground corresponds to the multiple double vertical lines in the FSS shown in FIG. 3A when the FSS is installed on a vehicle windshield in the orientation shown in FIG. 3A.

As another shape of FSS, FSS 30b shown in FIG. 3B has conductive parts 31b and non-conductive parts 32b, and is a circular loop slot shape in which multiple ring-shaped non-conductive parts 32b are formed in a plan view. In FSS 30b having such a shape, the hexagons constituting part A are arranged in a regular triangular pattern (along the XY plane) with no gaps so as to share each side of the hexagon, so that the circular loop slot can be filled efficiently. FSS 30b shown in FIG. 3B has the advantage of being able to reduce the inter-slot distance compared to the square arrangement such as FSS 30a shown in FIG. 3A, and therefore has the advantage of being able to increase the degree of design freedom.

In the above-mentioned portion A in the FSS 30b in Fig. 3B, the length p from each vertex of the hexagon to the center (center of gravity), the radius t of the imaginary circle c passing through the center of the width W of the ring-shaped non-conductive portion 32b, and the length of the width W of the ring-shaped non-conductive portion 32b can be set appropriately. The radius t is shorter than the length p, and the width W is shorter than the length p.

The length p is preferably 0.25 mm to 3 mm, t is preferably 0.3 mm to 1.5 mm, and the width W is preferably 0.03 mm to 1 mm. The loading area of the FSS 30b in the FSS loading member can also be appropriately determined, but when the wavelength in air corresponding to the frequency F of the transmitted radio wave is λ (mm), it is preferably λ ² mm ² or more, more preferably 2λ ² mm ² or more, and even more preferably 3λ ² mm ² or more.

The width W of the non-conductive portion is more preferably 250 μm or less, and even more preferably 200 μm or less. In other words, the width W is more preferably 30 μm to 250 μm, and even more preferably 30 μm to 200 μm. By having the width W of the non-conductive portion within the above range, the electric field is concentrated in the non-conductive portion, which effectively acts as a capacitance, improving radio wave transparency.

In the FSS 30b shown in FIG. 3B, the length p, radius t, and width W of each part A of the ring-shaped non-conductive part 32b can be appropriately designed within the above numerical range. The non-conductive part 32c may also be designed so that the distance between the centers of adjacent ring-shaped non-conductive parts is equal. In other words, in a plan view, a regular hexagonal part A consisting of the conductive part 31c and the non-conductive part 32c is taken as one unit, and the regular hexagonal part A may have a circular loop slot shape consisting of the ring-shaped non-conductive part 32b that has the same center as the center of the regular hexagon and is formed inside the regular hexagon, and the other conductive parts 31b.

In addition, when the FSS loading member according to this embodiment is used as a window member, it is preferable that the non-conductive portion of the FSS has at least one component horizontal and/or vertical to the ground. Here, the component horizontal to the ground corresponds to the upper and lower parts of a circle in the FSS shown in FIG. 3B when the FSS is installed on a vehicle windshield in the orientation shown in FIG. 3B. In addition, the component vertical to the ground corresponds to the left and right parts of a circle in the FSS shown in FIG. 3B when the FSS is installed on a vehicle windshield in the orientation shown in FIG. 3B.

In addition, when the FSS loading member in this embodiment has multiple FSSs, the FSS loading member can be designed by arbitrarily combining the FSS shape patterns in the planar view described above for each FSS.

The thickness of the FSS is not particularly limited, but from the viewpoint of improving radio wave transmission, it is preferably 0.1 mm or less, more preferably 0.05 mm or less, and even more preferably 0.02 mm or less. In addition, from the viewpoint of stability as a conductive film, the thickness of the FSS may be 0.003 μm or more, preferably 0.005 μm or more, and more preferably 0.010 μm or more.

The FSS selectively transmits radio waves of a predetermined frequency F, and the predetermined frequency F that transmits through the FSS loading member is preferably within the range of 1 GHz to 100 GHz.

In addition, from the viewpoint of improving the radio wave transparency of the FSS loading member by the FSS, it is preferable that the radio wave of frequency F is 10 GHz or more, and even more preferable that it is 20 GHz or more.

The upper limit of frequency F is not particularly limited, but may be, for example, 90 GHz or less, or 80 GHz or less. For example, in the case of laminated glass for vehicles, there is a tendency for radio waves with a frequency F of 10 GHz or more to be attenuated significantly, and loading an FSS for radio waves with a frequency F of 10 GHz or more is effective in improving radio wave transparency.

The total thickness of the FSS loading member according to this embodiment is preferably 1.5 mm or more, more preferably 2.0 mm or more, and more preferably 4.0 mm or more, for reasons of ease of handling and ease of maintaining a predetermined strength. Here, the total thickness of the FSS loading member refers to the thickness of the FSS loading member in the area where the FSS is loaded in a plan view. There is no particular limit to the total thickness of the FSS loading member according to this embodiment, but it is preferably 40 mm or less, more preferably 30 mm or less, for reasons such as the weight of the FSS loading member being large.

Hereinafter, a preferred loading mode of the FSS in the FSS loading member according to this embodiment will be described. In addition, when the FSS loading member according to this embodiment has multiple FSSs, the FSS loading member can be designed by arbitrarily combining the loading patterns described below for each FSS.

It is preferable that the laminated member of the FSS loading member according to this embodiment has two continuous intermediate bodies as dielectric layers, and an FSS is provided between the two continuous intermediate bodies. That is, among the dielectric layers constituting the laminated member in the FSS loading member 20 shown in FIG. 4, two continuous dielectric layers are both intermediate bodies, and an FSS is provided between the first intermediate body 21 and the second intermediate body 22 at a. In this case, n is an integer of 4 or more.

In addition, it is preferable that the two successive intermediates (dielectric layers) are both made of a resin material, and it is more preferable that they are both made of the same resin material. For example, the first intermediate 21 and the second intermediate 22 may both be made of PVB or EVA. If the first intermediate 21 and the second intermediate 22 are made of the same material, this is preferable because it improves adhesion and reduces changes in optical properties at their interface and changes in physical properties such as thermal expansion due to temperature changes.

By providing the FSS between the intermediate bodies in this way, the FSS loading member is configured so that the distance (d1) from the FSS to the surface on the outside of the vehicle (the surface of the nth layer opposite the n-1th layer) and the distance (d2) from the FSS to the surface on the inside of the vehicle (the surface of the first layer opposite the second layer) are approximately the same in the radio wave transmission direction, making them approximately symmetrical. In other words, the FSS is provided at a position where the distances (d1, d2) from the two outermost surfaces of the FSS loading member are approximately the same. This effectively reduces reflection of the entire FSS loading member, improving radio wave transmission.

Here, the distance (d1) from the FSS to the surface on the outer side of the vehicle and the distance (d2) to the surface on the inner side of the vehicle being substantially the same means that d1/d2 or d2/d1 is in the range of 90% to 110%. d1/d2 or d2/d1 is preferably in the range of 95% to 105%, more preferably in the range of 97% to 103%, and even more preferably in the range of 98% to 102%.

In particular, when the FSS-loaded member is used as a vehicle window glass, the number of layers n of the dielectric layer is set to 4, and the layers are arranged in the order of the first layer, namely, the first glass substrate, the first resin layer, the second resin layer, and the second glass substrate. In this case, it is preferable that the thickness of the first glass substrate and the thickness of the second glass substrate are substantially the same, and that the thickness of the first resin layer and the thickness of the second resin layer are substantially the same. In this case, it is preferable to provide an FSS between two successive intermediate bodies (the first resin layer and the second resin layer). It is more preferable that the materials of the first glass substrate and the second glass substrate are the same, and that the materials of the first resin layer and the second resin layer are the same.

In addition, when the FSS-loaded member is used as a vehicle window glass, the number of layers n of the dielectric layer may be set to 5, and the layers may be, in order from the first layer, a first glass substrate, a first resin layer, a third resin layer, a second resin layer, and a second glass substrate. In this case, it is preferable that the thickness of the first glass substrate is approximately the same as that of the second glass substrate, and that the thickness of the first resin layer is approximately the same as that of the second resin layer. It is also preferable that the FSS is provided on the third resin layer, so that the FSS is provided between two successive intermediate bodies (the first resin layer and the third resin layer, or the second resin layer and the third resin layer).

Here, the third resin layer can be a resin layer such as PET that is very thin compared to the total thickness of the FSS loading member, and in this case, the thickness of the third resin layer in the FSS loading member can be ignored. Therefore, in the radio wave transmission direction of the FSS loading member, the distance from the FSS to the surface on the vehicle exterior side (the surface of the nth layer opposite the n-1th layer) is approximately the same as the distance to the surface on the vehicle interior side (the surface of the first layer opposite the second layer).
It is more preferable that the first glass substrate and the second glass substrate are made of the same material, and that the first resin layer and the second resin layer are made of the same material.

In addition, the FSS loading member according to this embodiment may be provided with an FSS on at least one of the two outermost surfaces of the laminated member. That is, an FSS may be provided on at least one of the outermost surface a on the first layer side and the outermost surface b on the nth layer side of the FSS loading member 30 shown in FIG. 5. In this way, the FSS loading member according to this embodiment has an FSS on at least one of the two outermost surfaces of the laminated member, which can efficiently reduce reflection at the outermost surface, thereby improving radio wave transparency. Furthermore, the FSS loading member according to this embodiment may be provided with an FSS on both of the two outermost surfaces of the laminated member.

The manufacturing method of the FSS-loaded member according to this embodiment is not particularly limited. The method of loading the FSS on the main surface of the dielectric layer may be directly or indirectly formed on the main surface of the dielectric layer. For example, the FSS may be formed by patterning a conductive layer on a film such as a resin in advance, and the FSS together with the resin may be attached to the main surface of the dielectric layer. Alternatively, the FSS may be directly loaded on the main surface of the dielectric layer by plating or sputtering a desired metal on the main surface of the dielectric layer. After that, the FSS-loaded member may be obtained by stacking dielectric layers such as a dielectric substrate or intermediate body and undergoing a process of heating and pressing.

The present invention is explained in detail below with reference to examples, but the present invention is not limited to these.

[Measurement of sheet resistance of FSS conductive part]
The sheet resistance of the conductive portion of the FSS in the examples and comparative examples was measured using a non-contact eddy current resistance measuring device, 717 Conductance Monitor, manufactured by DELCOM.

[FSS Dimension Measurement]
Various dimensions of the FSS in the examples and comparative examples were measured using an optical microscope DSX-500 manufactured by Olympus.

[Optical property evaluation]
The transmission and reflection spectra from 250 nm to 2500 nm were measured using a Hitachi U-4100 spectrophotometer, and the solar reflectance Re, solar transmittance Te, visible light reflectance Rv, visible light reflection color tone (Rva ^* , Rvb ^* ), visible light transmittance Tv, and visible light transmission color tone (Ta ^* , Tb ^* ) were calculated based on ISO 9050:2003.

[Radio wave transmission evaluation]
The reflection characteristic (S11) and transmission characteristic (S21) were calculated for the FSS-loaded member or laminated member in the examples and comparative examples when vertically polarized waves (TM waves) or horizontally polarized waves (TE waves) of 28 GHz or 78 GHz were incident at a predetermined incident angle. The values at 28 GHz and 78 GHz were calculated based on the values of the relative dielectric constant _εr and the dielectric tangent tan δ (δ is the loss angle) of each material used at 1 GHz. Here, the incident angle means the angle of the incident direction of the radio wave of frequency F from the normal to the main surface of the FSS-loaded member.

Specifically, the antennas were placed facing each other, and the FSS-loaded member or laminated member obtained was placed between them so that the incident angle was a predetermined angle. Then, the reflection characteristic (S11) and transmission characteristic (S21) were measured for vertically polarized waves (TM waves) or horizontally polarized waves (TE waves) of 28 GHz or 78 GHz at an opening of 100 mmφ, with the case without the radio wave-transparent substrate being set to 0 [dB].

[Fabrication of FSS loading members]
The FSS loading members were fabricated in the following manner: Examples 1, 3, and 4 correspond to working examples, and Example 2 corresponds to a comparative example.

<Example 1>
First, a multilayer film containing Ag and zinc oxide was formed on a PET film having a thickness of 0.1 mm by a sputtering method so that the sheet resistance was 2Ω/□, and then a first frequency selective surface F11 having a double lattice stripe pattern as shown in Fig. 3A was formed using a laser having a wavelength of 532 nm. The dimensions of each part of the frequency selective surface F11 shown in Fig. 3A were width G: 0.03 mm, L1: 0.2 mm, and L2: 0.24 mm.

6, the first dielectric substrate 111 made of 1.98 mm thick soda lime glass, the first intermediate 112 made of 0.38 mm thick PVB film, the first frequency selective surface F11, the third intermediate 113 made of 0.1 mm thick PET film, the second intermediate 114 made of 0.38 mm thick PVB film, and the second dielectric substrate 115 made of 1.98 mm thick soda lime glass were laminated in this order, and the frequency selective surface loading member 110 of Example 1 was produced by heating at 130°C for 90 minutes under a pressure of 1 MPa and slowly cooling. The first dielectric substrate 111, the first intermediate 112, the third intermediate 113, the second intermediate 114, and the second dielectric substrate 115 all have a main surface that is a square of 300 mm x 300 mm. The relative dielectric constant, dielectric loss tangent, thickness, various dimensions of the FSS, transmission phase, and total thickness of the dielectric substrate and intermediate body are shown in Table 1.

<Example 2>
A first intermediate 212 made of a PVB film having a thickness of 0.76 mm was inserted between a first dielectric substrate 211 made of soda lime glass having a thickness of 1.98 mm and a square having a main surface of 300 mm x 300 mm and a second dielectric substrate 213 made of soda lime glass having a thickness of 1.98 mm, and heated at 130 ° C for 90 minutes under a pressure of 1 MPa and slowly cooled to produce a laminate member 210 of Example 2 shown in Figure 7. The first dielectric substrate 211, the first intermediate 212, and the second dielectric substrate 213 all have a square main surface of 300 mm x 300 mm. The relative dielectric constant, dielectric loss tangent, thickness, and total thickness of the dielectric substrate and intermediate are shown in Table 1.

<Example 3>
A 10 μm thick Cu film is plated on a 0.38 mm thick PVB film, and then etched to form a double lattice striped first frequency selective surface F11 on the PVB film as shown in Fig. 3A. The dimensions of each part of the first frequency selective surface F11 shown in Fig. 3A are width G: 0.03 mm, L1: 0.16 mm, and L2: 0.26 mm.
Next, as shown in Fig. 6, the first dielectric substrate 111 having a square main surface of 300 mm x 300 mm and made of borosilicate glass having a thickness of 2.00 mm, the first intermediate 112 made of a PVB film having a thickness of 0.38 mm, the first frequency selective surface F11, the second intermediate 114 made of a PVB film having a thickness of 0.38 mm, and the second dielectric substrate 115 made of borosilicate glass having a thickness of 2.00 mm are laminated in this order, and the members are heated at 130 ° C. for 90 minutes under a pressure of 1 MPa and slowly cooled to produce the frequency selective surface loading member 110 of Example 3. In this example, the third intermediate 113 shown in Fig. 6 is not provided. The relative dielectric constant, dielectric loss tangent, thickness, and total thickness of the dielectric substrate and intermediate are shown in Table 1.

<Example 4>
A 10 μm thick Cu film is plated on a 0.38 mm thick PVB film, and then etched to form a circular loop slot-shaped first frequency selective surface F11 on the PVB film as shown in Fig. 3B. The dimensions of each part of the frequency selective surface F51 shown in Fig. 3B are p: 0.54 mm, t: 0.44 mm, and W: 0.055 mm, forming a periodic regular hexagonal pattern.
Next, as shown in Fig. 6, the first dielectric substrate 111, which is a square of 300 mm x 300 mm on the main surface and is made of soda lime glass having a thickness of 1.98 mm, the first intermediate 112, which is made of a PVB film having a thickness of 0.38 mm, the first frequency selective surface F11, the second intermediate 114, which is made of a PVB film having a thickness of 0.38 mm, and the second dielectric substrate 115, which is made of soda lime glass having a thickness of 1.98 mm, are laminated in this order, and heated at 130 ° C. for 90 minutes under a pressure of 1 MPa and slowly cooled to produce the frequency selective surface loading member 110 of Example 4. In this example, the third intermediate 113 shown in Fig. 6 is not provided. The relative dielectric constant, dielectric loss tangent, thickness, and total thickness of the dielectric substrate and intermediate are shown in Table 1.

In addition, the results of the optical property evaluation of the frequency selective surface loading members or laminated members of Examples 1 to 4 are shown in Table 2, and the results of the radio wave transmittance evaluation are shown in Table 3.

Comparing Example 1 and Example 2 from the results in Table 2, the FSS-loaded member of Example 1, in which the FSS was placed at a designated position, had a higher solar reflectance and a lower solar transmittance than Example 2, in which no FSS was provided. Comparing Example 2 with Example 3 and Example 4, the FSS-loaded members of Example 3 and Example 4, in which the FSS was placed at a designated position, had a higher solar reflectance and a lower solar transmittance than Example 2, in which no FSS was provided.

In addition, from the results of Table 3, comparing Example 1 and Example 2, the FSS loading member of Example 1 in which the FSS was arranged at a predetermined position had a lower reflection characteristic S11 and a higher transmission characteristic S21 at 78 GHz than Example 2 in which no FSS was provided, and thus the radio wave transmission was improved. In addition, comparing Examples 3 and 4 with Example 2, the FSS loading members of Examples 3 and 4 in which the FSS was arranged at a predetermined position had a lower reflection characteristic S11 and a higher transmission characteristic S21 at 78 GHz than Example 2 in which no FSS was provided, and thus the radio wave transmission was improved.
Therefore, it was found that the FSS loading member of the present invention has good thermal properties and radio wave transmittance.

Although various embodiments have been described above with reference to the drawings, it goes without saying that the present invention is not limited to such examples. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the claims, and it is understood that these naturally fall within the technical scope of the present invention. Furthermore, the components in the above embodiments may be combined in any manner as long as it does not deviate from the spirit of the invention.

This application is based on a Japanese patent application (Patent Application No. 2020-131976) filed on August 3, 2020, the contents of which are incorporated by reference into this application.

10, 20, 30, 110 Frequency selective surface loading member 111, 115, 211, 213 Dielectric substrate 21, 22, 112, 113, 114 Intermediate body 210 Laminate member 30a, 30b, F11 Frequency selective surface 31a, 31b Conductive portion 32a, 32b Non-conductive portion

Claims (24)

A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less,
A frequency selective surface loading member, wherein the laminated member has two continuous intermediate bodies as a dielectric layer other than the outermost dielectric layer of the laminated member, and the frequency selective surface is provided between the two continuous intermediate bodies . The frequency selective surface loading member according to claim 1 , wherein the two successive intermediate bodies are made of the same resin material. The frequency selective surface loading member according to claim 2 , wherein the resin material is PVB or EVA. The frequency selective surface loading member according to any one of claims 1 to 3 , wherein the first layer and the nth layer are glass substrates. The frequency selective surface loading member according to any one of claims 1 to 3 , wherein the first layer or the nth layer is a shielding layer that blocks visible light, and in a planar view of the laminated member, at least a portion of the frequency selective surface overlaps with the shielding layer. 6. The frequency selective surface loading member of claim 5 , wherein the dielectric layer adjacent to the shielding layer is a glass substrate. A frequency selective surface loading member according to any one of claims 1 to 6, wherein the distance from the frequency selective surface to the surface of the first layer opposite the second layer is approximately the same as the distance from the frequency selective surface to the surface of the nth layer opposite the (n-1 ) th layer. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
The laminated member is a frequency selective surface loading member that is composed of four dielectric layers, in which a first glass substrate, a first resin layer, a second resin layer, and a second glass substrate are laminated in this order from the first layer. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified by ISO9050:2003 is 54% or less ,
The laminated member is a frequency selective surface loading member consisting of five dielectric layers, in which a first glass substrate, a first resin layer, a third resin layer, a second resin layer, and a second glass substrate are laminated in this order from the first layer. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
A frequency selective surface loading member, wherein the frequency selective surface is provided on at least one of the two outermost surfaces of the laminated member. The frequency selective surface loading member according to any one of claims 1 to 10 , which has a visible light transmittance as defined in ISO9050:2003 of 60% or more. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
A frequency selective surface loading member having a solar reflectance of 8% or more as specified in ISO 9050:2003. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
A frequency selective surface loading member having a visible light reflectance of 15% or less as specified in ISO 9050:2003. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
A frequency selective surface loading member having a visible light reflection color tone Rva ^* of -10 to 5 and Rvb ^* of -10 to 10 as specified in ISO9050:2003. A laminated member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
A frequency selective surface loading member having a visible light transmission color tone Ta ^* of -8 to 5 and a visible light transmission color tone Tb ^* of -8 to 6 as specified in ISO9050:2003. The frequency selective surface loading member according to any one of claims 1 to 15 , wherein the width G of the non-conductive portion of the frequency selective surface is between 0.01 mm and 0.5 mm. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
A frequency selective surface loading member, wherein the sheet resistance of the conductive portion of the frequency selective surface is 50 Ω/□ or less. A laminate member having a total of n dielectric layers laminated in order from a first layer to an nth layer (where n is an integer of 3 or more),
At least one of the main surfaces of the dielectric layer constituting the laminated member is provided with a frequency selective surface that transmits radio waves of a predetermined frequency F;
the frequency selective surface having a conductive portion and a non-conductive portion;
The solar transmittance as specified in ISO9050:2003 is 54% or less ,
A frequency selective surface loading member, wherein the conductive portion of the frequency selective surface comprises at least one selected from the group consisting of Ag, ITO, tin oxide doped with at least one of fluorine and antimony, and Cu. A frequency selective surface loading member according to any one of claims 1 to 18 , wherein when the frequency selective surface loading member is used as a window member, the non-conductive portion of the frequency selective surface has at least one component horizontally and vertically relative to the ground. The frequency selective surface loading member according to any one of claims 1 to 19 , having, in a plan view, a first region having the frequency selective surface and a second region not having the frequency selective surface. The frequency selective surface loading member according to claim 20 , wherein, in a plan view, an outer edge of the first region is located inside an outer edge of the second region. The frequency selective surface loading member according to any one of claims 1 to 21 , wherein the frequency F is in the range of 1 GHz to 100 GHz. A window member for a vehicle, comprising the frequency selective surface loading member according to any one of claims 1 to 22 . 24. The vehicle window component of claim 23 , wherein the frequency selective surface loading component is a windshield for a vehicle.

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