Laminate, antenna substrate, and antenna module

Abstract

The present invention provides a laminate and applications thereof, the laminate including a dielectric layer with a relative permittivity of over 3 and conductor layers, in which two or more types of conductor layers of different sizes are disposed on one surface side of the dielectric layer, a conductor layer different from the two or more types of conductor layers is disposed on the other surface side of the dielectric layer, and the two or more types of conductor layers are disposed in the same plane and do not contact each other.

Description

Laminate, antenna substrate, and antenna module

[0001] The present disclosure relates to a laminate, an antenna substrate, and an antenna module.

[0002] In recent years, communication devices have become faster and faster, and the frequencies used in communication have tended to become much higher, which has led to increased demands for miniaturization and high-density packaging of the electronic components used.

[0003] For example, WO 2023 / 120467 describes an antenna module comprising: a first ground electrode; a dielectric substrate arranged in the vicinity of the first ground electrode; and a first radiating element and a second radiating element arranged on the dielectric substrate substantially parallel to the first ground electrode, each radiating radio waves; the second radiating element is arranged at a position higher than the first radiating element; the first radiating element has, when viewed in a plan view from the height direction, an overlapping portion that overlaps with the second radiating element and a non-overlapping portion that does not overlap with the second radiating element; the dielectric substrate has an upper surface located above the second radiating element and a first step surface located above the non-overlapping portion of the first radiating element and below the second radiating element; and a high-dielectric layer having a higher dielectric constant than the dielectric substrate is arranged in a peripheral region of the upper surface and a peripheral region of the first step surface. WO 2023 / 145327 describes a thermosetting resin composition containing (A) a thermosetting resin and (B) at least one inorganic filler selected from the group consisting of titanium-based inorganic fillers and zircon-based inorganic fillers, in which the content of particles having a particle size of 1.0 μm or less in component (B) is 30% by volume or less based on component (B), and describes that the thermosetting resin composition is used in an antenna module.

[0004] Antenna modules are required to be compatible with signals in a plurality of high frequency bands and to be miniaturized.

[0005] An object of an embodiment of the present disclosure is to provide a laminate and an antenna substrate that are compatible with signals in multiple high frequency bands and are suitable for an antenna module. Another object of an embodiment of the present disclosure is to provide an antenna module that is compatible with signals in multiple high frequency bands.

[0006] Specific means for solving the problems are as follows: <1> A laminate comprising a dielectric layer having a relative permittivity of more than 3 and a conductor layer, wherein two or more types of conductor layers different in size are arranged on one surface of the dielectric layer, and a conductor layer different from the two or more types of conductor layers is arranged on the other surface of the dielectric layer, and the two or more types of conductor layers are arranged in the same plane and not in contact with each other. <2> The laminate according to <1>, wherein the dielectric layer satisfies the following formula A, where T is the relative permittivity and D is the dielectric loss tangent. T ０．５×D≦0.10... Formula A <3> The laminate according to <1> or <2>, wherein the two or more types of conductor layers are arranged in a staggered pattern. <4> The laminate according to any one of <1> to <3>, wherein the dielectric layer has a dielectric dissipation factor of less than 0.01. <5> The laminate according to any one of <1> to <4>, wherein the dielectric layer contains an inorganic filler and a resin. <6> The laminate according to <5>, wherein the inorganic filler has a relative dielectric constant of 6 to 20,000. <7> The laminate according to <5> or <6>, wherein the inorganic filler contains at least one selected from the group consisting of barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, zirconium titanate, zinc titanate, titanium dioxide, magnesium oxide, alumina, tantalum pentoxide, and niobium pentoxide. <8> The laminate according to any one of <5> to <7>, wherein in the dielectric layer, the ratio (Do / Di) of the number of inorganic filler particles per unit area in the in-plane direction (Di) to the number of inorganic filler particles per unit area in the thickness direction (Do) is 0.5 or more. <9> The laminate according to any one of <5> to <8>, wherein the resin includes at least one selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer, a semi-cured product of a thermosetting resin, a cured product of a thermosetting resin, a semi-cured product of a thermosetting elastomer, and a cured product of a thermosetting elastomer. <10> The laminate according to any one of <1> to <9>, wherein the conductor layer has a surface roughness Rc on the dielectric layer side of 1 μm or less. <11> The laminate according to any one of <1> to <10>, wherein the two or more types of conductor layers have different signal frequencies. <12> An antenna substrate including the laminate according to any one of <1> to <11>. <13> An antenna module that transmits and receives radio waves having a frequency of 6 GHz to 24 GHz, including the antenna substrate according to <12>. <14> An antenna module that transmits and receives radio waves having a frequency of 0.5 GHz to 5.9 GHz, including the antenna substrate according to <12>.

[0007] According to an embodiment of the present disclosure, there is provided a laminate and an antenna substrate that are compatible with signals in multiple high frequency bands and are suitable for an antenna module. Also, according to an embodiment of the present disclosure, there is provided an antenna module that is compatible with signals in multiple high frequency bands.

[0008] Fig. 1 is a schematic plan view showing the arrangement of conductor layers in a laminate of the present disclosure. Fig. 2 is a schematic plan view showing the arrangement of conductor layers in a laminate of Example 2. Fig. 3 is a schematic plan view showing the arrangement of conductor layers in a laminate of Example 6.

[0009] The contents of the present disclosure are described in detail below. The following description of the constituent elements may be based on a representative embodiment of the present disclosure, but the present disclosure is not limited to such an embodiment. In this specification, the term "to" indicating a numerical range is used to mean that the numerical values ​​before and after it are included as the upper and lower limits. In the numerical ranges described in stages in this disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the examples. Furthermore, in the description of groups (atomic groups) in this specification, a notation that does not specify whether they are substituted or unsubstituted encompasses both unsubstituted and substituted groups. For example, the term "alkyl group" encompasses not only alkyl groups without substituents (unsubstituted alkyl groups) but also alkyl groups with substituents (substituted alkyl groups). In this specification, "(meth)acrylic" is a term used to conceptually encompass both acrylic and methacrylic, and "(meth)acryloyl" is a term used to conceptually encompass both acryloyl and methacryloyl. Furthermore, the term "process" in this specification includes not only an independent process but also a process that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved. Furthermore, in this disclosure, a combination of two or more preferred aspects is a more preferred aspect. Furthermore, unless otherwise specified, the weight-average molecular weight (Mw) and number-average molecular weight (Mn) in this disclosure are molecular weights determined by a gel permeation chromatography (GPC) analyzer using a TSKgel Super HM-H (trade name of Tosoh Corporation) column, a PFP (pentafluorophenol) / chloroform solvent (mass ratio) = 1 / 2, a differential refractometer, and conversion using polystyrene as a standard substance. The average particle size (e.g., D50) of the inorganic filler in the present disclosure is measured using a laser diffraction / scattering particle size distribution analyzer, such as the LA-950V2 manufactured by HORIBA.

[0010] [Laminate] The laminate of the present disclosure includes a dielectric layer having a relative dielectric constant of greater than 3 and a conductor layer, and two or more types of conductor layers different from each other in size are arranged on one surface side of the dielectric layer, and a conductor layer different from the two or more types of conductor layers is arranged on the other surface side of the dielectric layer, and the two or more types of conductor layers are arranged in the same plane and so as not to contact each other.

[0011] "Within the same plane" means that the surfaces in contact with the conductor layers are the same plane, and the heights from the surface of two or more types of conductor layers may be different from each other.

[0012] In the laminate of the present disclosure, two or more types of conductor layers of different sizes are arranged on the same plane and do not come into contact with each other, making it possible to accommodate high-frequency band signals and to miniaturize the antenna module that is formed.

[0013] On the other hand, WO 2023 / 120467 and WO 2023 / 145327 do not describe arranging two or more types of conductor layers of different sizes on the same plane and not in contact with each other. In particular, in WO 2023 / 120467, the first radiating element and the second radiating element are arranged in the vertical direction, which is thought to result in large propagation loss of radio waves.

[0014] <Dielectric Layer> The laminate of the present disclosure includes a dielectric layer having a relative dielectric constant greater than 3. The relative dielectric constant of the dielectric layer is preferably 4.5 to 1,000, more preferably 5 to 500, more preferably 10 to 100, even more preferably greater than 10 but not greater than 100, and most preferably 20 to 80. By setting the relative dielectric constant within the above range, the size of the conductor layer formed on the dielectric layer can be designed to be small. Since the spacing between conductor layers can be increased, the number of conductor layers can be increased and the interaction between conductor layers can be reduced. This increases the degree of design freedom and improves energy efficiency.

[0015] From the viewpoint of reducing energy loss on the substrate and increasing the energy efficiency of the device, it is preferable that the dielectric layer satisfies the following formula A, where T is the relative permittivity and D is the dielectric loss tangent: T ０．５ ×D≦0.10… Formula A “T ０．５ ×D" is preferably 0.10 or less, more preferably 0.050 or less, and even more preferably 0.020 or less. ０．５ ×D" is preferably 0.0001 or more, and more preferably 0.0010 or more.

[0016] The dielectric loss tangent of the dielectric layer is preferably 0.03 or less, more preferably less than 0.01, further preferably 0.0001 to 0.009, and most preferably 0.001 to 0.008.

[0017] In the present disclosure, the dielectric constant and the dielectric loss tangent are measured by the following method. The dielectric constant and the dielectric loss tangent are measured at a frequency of 10 GHz by a resonance perturbation method. A 10 GHz cavity resonator (CP531 manufactured by Kanto Electronics Application Development Co., Ltd.) is connected to a network analyzer (E8363B manufactured by Agilent Technology Corporation), a polymer film is inserted into the cavity resonator, and the change in the resonance frequency before and after insertion for 96 hours is measured in an environment of 25°C temperature and 60% RH.

[0018] The dielectric layer preferably contains an inorganic filler and a resin from the viewpoint of making the relative dielectric constant greater than 3. The combination of the relative dielectric constant and the dielectric loss tangent can be controlled by the type and content of the inorganic filler and resin, the orientation state and aggregation state of the inorganic filler, etc.

[0019] (Inorganic Filler) Examples of inorganic fillers contained in the dielectric layer include barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, zirconium titanate, zinc titanate, titanium dioxide, magnesium oxide, alumina, tantalum pentoxide, and niobium pentoxide.

[0020] The inorganic filler preferably contains at least one selected from the group consisting of barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, zirconium titanate, zinc titanate, titanium dioxide, magnesium oxide, alumina, tantalum pentoxide, and niobium pentoxide. Among these, the inorganic filler is more preferably barium titanate or titanium oxide.

[0021] The inorganic filler preferably has a relative dielectric constant of 6 to 20,000 at 25° C. and a frequency of 10 GHz, and more preferably 20 to 20,000.

[0022] From the viewpoint of achieving both an orientation state and dielectric properties, the average particle size of the inorganic filler is preferably 0.01 μm to 10 μm, more preferably 0.02 μm to 2 μm, and particularly preferably 0.03 μm to 5 μm.

[0023] The average particle size is measured using a laser diffraction / scattering particle size distribution analyzer, such as the LA-950V2 manufactured by HORIBA.

[0024] The shape of the inorganic filler is not particularly limited, and may be amorphous or spherical. From the viewpoint of increasing the content in the dielectric layer and improving the relative dielectric constant of the dielectric layer, the shape of the inorganic filler is preferably spherical.

[0025] In the dielectric layer, the ratio (Do / Di) of the number of inorganic fillers per unit area in the in-plane direction (Di) to the number of inorganic fillers per unit area in the thickness direction (Do) is preferably 0.5 or more. For example, when the inorganic filler is oriented in the in-plane direction, Di tends to increase and Do tends to decrease, resulting in a decrease in Do / Di. When the inorganic filler is oriented in the thickness direction, Di tends to decrease and Do tends to increase, resulting in an increase in Do / Di. In the process of forming the dielectric layer, by controlling the orientation state of the inorganic filler so that Do / Di is 0.5 or more, the relative dielectric constant and dielectric loss tangent can be set within suitable ranges. Do / Di is preferably 0.7 to 1,000, more preferably 0.85 to 100, and even more preferably 0.9 to 10. When Do / Di is 0.5 or more, the inorganic filler is oriented in the thickness direction appropriately, so that the amount of dielectric in the electric field direction increases, and the relative dielectric constant increases efficiently. On the other hand, since the dielectric loss tangent changes depending on the content of the inorganic filler, by promoting the orientation of the inorganic filler in the thickness direction, the relative dielectric constant and the dielectric loss tangent fall within suitable ranges.

[0026] Di and Do are measured by the following method: The dielectric layer is cut using a microtome. The number of inorganic fillers per unit area is measured by morphological observation using a scanning electron microscope. The ratio (Do / Di) is calculated from the obtained Di and Do.

[0027] The dielectric layer may contain only one type of inorganic filler or two or more types of inorganic fillers. From the viewpoint of achieving both dielectric properties and mechanical properties, the content of the inorganic filler is preferably 10 to 90% by volume, more preferably 30 to 80% by volume, and even more preferably 50 to 70% by volume.

[0028] The inorganic filler may be surface-treated with an inorganic or organic substance, for example, by (1) coating, (2) topochemical modification, (3) mechanochemical modification, (4) encapsulation, or (5) irradiation.

[0029] (Resin) Examples of resins contained in the dielectric layer include thermoplastic resins, thermoplastic elastomers; semi-cured or cured thermosetting resins; and semi-cured or cured thermosetting elastomers.

[0030] The resin preferably includes at least one selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer, a semi-cured product of a thermosetting resin, a cured product of a thermosetting resin, a semi-cured product of a thermosetting elastomer, and a cured product of a thermosetting elastomer.

[0031] Examples of thermoplastic resins include polyester resins (including liquid crystal polymers), cyanate resins, coumarone resins, polyurethane resins, (meth)acrylic resins, polystyrene resins, fluororesins, polyimide resins, fluorinated polyimide resins, polyamide resins, polyamideimide resins, polyetherimide resins, cellulose acylate resins, polyether ether ketone resins, polycarbonate resins, polyolefin resins (e.g., polyethylene resins, polypropylene resins, resins made of cyclic olefin copolymers, alicyclic polyolefin resins), polyarylate resins, polyethersulfone resins, polysulfone resins, fluorene ring-modified polycarbonate resins, alicyclic ring-modified polycarbonate resins, and fluorene ring-modified polyester resins.

[0032] Examples of thermoplastic elastomers include elastomers containing structural units derived from styrene (polystyrene elastomers), polyester elastomers, polyolefin elastomers, polyurethane elastomers, polyamide elastomers, polyacrylic elastomers, silicone elastomers, and polyimide elastomers. The thermoplastic elastomer may be a hydrogenated product.

[0033] Examples of polystyrene elastomers include styrene-butadiene-styrene block copolymers (SBS), styrene-isoprene-styrene block copolymers (SIS), polystyrene-poly(ethylene-propylene) diblock copolymers (SEP), polystyrene-poly(ethylene-propylene)-polystyrene triblock copolymers (SEPS), styrene-ethylene-butylene-styrene block copolymers (SEBS), and polystyrene-poly(ethylene / ethylene-propylene)-polystyrene triblock copolymers (SEEPS), styrene-isobutylene-styrene block copolymers (SIBS), and hydrogenated products thereof.

[0034] Examples of thermosetting resins include epoxy resins which are monomers, oligomers, or polymers having two or more epoxy groups in one molecule, and the molecular weight and molecular structure are not particularly limited.

[0035] stilbene-type epoxy resins; novolac-type epoxy resins such as phenol novolac-type epoxy resins and cresol novolac-type epoxy resins; polyfunctional epoxy resins such as triphenolmethane-type epoxy resins and alkyl-modified triphenolmethane-type epoxy resins; aralkyl-type epoxy resins such as phenol aralkyl-type epoxy resins having a phenylene skeleton and phenol aralkyl-type epoxy resins having a biphenylene skeleton; naphthol-type epoxy resins such as dihydroxynaphthalene-type epoxy resins and epoxy resins obtained by glycidyl etherifying a dihydroxynaphthalene dimer; triazine-nucleus-containing epoxy resins such as triglycidyl isocyanurate and monoallyl diglycidyl isocyanurate; and bridged cyclic hydrocarbon compound-modified phenol-type epoxy resins such as dicyclopentadiene-modified phenol-type epoxy resins.

[0036] From the viewpoint of improving the balance between moisture resistance reliability and moldability, the epoxy resin is preferably at least one selected from the group consisting of bisphenol-type epoxy resins, novolac-type epoxy resins, biphenyl-type epoxy resins, phenol aralkyl-type epoxy resins, and triphenolmethane-type epoxy resins, and more preferably at least one selected from the group consisting of biphenyl-type epoxy resins and phenol aralkyl-type epoxy resins.

[0037] The semi-cured product of the thermosetting resin and the cured product of the thermosetting resin are preferably semi-cured and cured products of the thermosetting resin, respectively.

[0038] Examples of curing agents for curing epoxy resins include linear aliphatic diamines having 2 to 20 carbon atoms, such as ethylenediamine, trimethylenediamine, tetramethylenediamine, and hexamethylenediamine; metaphenylenediamine, paraphenylenediamine, paraxylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenylether, 4,4'-diaminodiphenylsulfone, 4,4'-diaminodicyclohexane, bis(4-aminophenyl)phenylmethane, 1,5-diaminonaphthalene, metaxylenediamine, paraxylenediamine, 1,1-bis(4-aminophenyl)cyclohexane, and dicyanodiamide; resol-type phenolic resins, such as aniline-modified resol resins and dimethyl ether resol resins; phenol novolac resins, cresol novolac resins, tert-butylphenol novolac resins, and novolac resins. phenol aralkyl resins such as phenylene skeleton-containing phenol aralkyl resins and biphenylene skeleton-containing phenol aralkyl resins; phenol resins having a condensed polycyclic structure such as a naphthalene skeleton or an anthracene skeleton; polyoxystyrenes such as polyparaoxystyrene; acid anhydrides including alicyclic acid anhydrides such as hexahydrophthalic anhydride (HHPA) and methyltetrahydrophthalic anhydride (MTHPA), and aromatic acid anhydrides such as trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), and benzophenonetetracarboxylic acid (BTDA); polymercaptan compounds such as polysulfide, thioester, and thioether; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; and organic acids such as carboxylic acid-containing polyester resins.

[0039] The curing agent may be used alone or in combination of two or more kinds.

[0040] The amount of the curing agent added is not particularly limited, but is, for example, preferably 0.1% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, and even more preferably 1% by mass to 5% by mass, relative to the total content of the resin and the curing agent.

[0041] Examples of the thermosetting elastomer include silicone rubber, fluororubber, and urethane rubber. Examples of the silicone rubber include vinyl group-containing organopolysiloxane.

[0042] The semi-cured product of the thermosetting elastomer and the cured product of the thermosetting elastomer are preferably semi-cured and cured products of the above-mentioned thermosetting elastomer, respectively.

[0043] In particular, the resin preferably contains a liquid crystal polymer.

[0044] The type of liquid crystal polymer is not particularly limited, and known liquid crystal polymers can be used. The liquid crystal polymer may be a thermotropic liquid crystal polymer that exhibits liquid crystallinity in a molten state, or a lyotropic liquid crystal polymer that exhibits liquid crystallinity in a solution state. In the case of a thermotropic liquid crystal, it is preferable that the polymer melts at a temperature of 450°C or less.

[0045] Examples of liquid crystal polymers include liquid crystal polyester, liquid crystal polyester amide in which an amide bond is introduced into liquid crystal polyester, liquid crystal polyester ether in which an ether bond is introduced into liquid crystal polyester, and liquid crystal polyester carbonate in which a carbonate bond is introduced into liquid crystal polyester.

[0046] From the viewpoint of liquid crystallinity, the liquid crystal polymer is preferably a polymer having an aromatic ring, and more preferably an aromatic polyester or an aromatic polyester amide.

[0047] The liquid crystal polymer may be a polymer in which an isocyanate-derived bond such as an imide bond, a carbodiimide bond, or an isocyanurate bond is further introduced into an aromatic polyester or an aromatic polyester amide.

[0048] The liquid crystal polymer is preferably a wholly aromatic liquid crystal polymer made using only aromatic compounds as raw material monomers.

[0049] Examples of liquid crystal polymers include the following: 1) A liquid crystal polymer obtained by polycondensation of (i) an aromatic hydroxycarboxylic acid, (ii) an aromatic dicarboxylic acid, and (iii) at least one compound selected from the group consisting of an aromatic diol, an aromatic hydroxyamine, and an aromatic diamine; 2) A liquid crystal polymer obtained by polycondensation of multiple aromatic hydroxycarboxylic acids; 3) A liquid crystal polymer obtained by polycondensation of (i) an aromatic dicarboxylic acid and (ii) at least one compound selected from the group consisting of an aromatic diol, an aromatic hydroxyamine, and an aromatic diamine; 4) A liquid crystal polymer obtained by polycondensation of (i) a polyester such as polyethylene terephthalate and (ii) an aromatic hydroxycarboxylic acid. Here, the aromatic hydroxycarboxylic acid, aromatic dicarboxylic acid, aromatic diol, aromatic hydroxyamine, and aromatic diamine may each independently be replaced with a derivative capable of polycondensation.

[0050] The melting point of the liquid crystal polymer is preferably higher than 260°C, more preferably higher than 260°C and not higher than 350°C, and even more preferably higher than 260°C and not higher than 330°C.

[0051] In the present disclosure, the melting point is measured using a differential scanning calorimeter. For example, it is measured using a product called "DSC-60A Plus" (manufactured by Shimadzu Corporation). The temperature rise rate in the measurement is 10°C / min.

[0052] The weight average molecular weight of the liquid crystal polymer is preferably 1,000,000 or less, more preferably 3,000 to 300,000, even more preferably 5,000 to 100,000, and particularly preferably 5,000 to 30,000.

[0053] From the viewpoint of further reducing the dielectric loss tangent, the liquid crystal polymer preferably contains an aromatic polyesteramide. The aromatic polyesteramide is a resin having at least one aromatic ring and having an ester bond and an amide bond. In particular, from the viewpoint of heat resistance, the aromatic polyesteramide is preferably a wholly aromatic polyesteramide.

[0054] The aromatic polyesteramide is preferably a crystalline polymer. The first phase preferably contains a crystalline aromatic polyesteramide. The crystalline aromatic polyesteramide further reduces the dielectric loss tangent. A crystalline polymer refers to one that has a clear endothermic peak rather than a stepwise change in endothermic amount in differential scanning calorimetry (DSC). Specifically, for example, this means that the half-width of the endothermic peak when measured at a heating rate of 10°C / min is within 10°C. Polymers with a half-width exceeding 10°C and polymers in which no clear endothermic peak is observed are considered amorphous polymers and are distinguished from crystalline polymers.

[0055] The aromatic polyester amide preferably contains a structural unit represented by the following formula 1, a structural unit represented by the following formula 2, and a structural unit represented by the following formula 3: １ -CO-...Formula 1 -CO-Ar ２ -CO-...Formula 2 -NH-Ar ３ -O-...Formula 3 In Formulas 1 to 3, Ar １ , Ar ２ , and Ar ３ each independently represents a phenylene group, a naphthylene group, or a biphenylylene group. Hereinafter, the structural unit represented by formula 1 may also be referred to as "unit 1", etc.

[0056] Unit 1 can be introduced, for example, by using an aromatic hydroxycarboxylic acid as a raw material. Unit 2 can be introduced, for example, by using an aromatic dicarboxylic acid as a raw material. Unit 3 can be introduced, for example, by using an aromatic hydroxylamine as a raw material.

[0057] Here, the aromatic hydroxycarboxylic acid, aromatic dicarboxylic acid, aromatic diol, and aromatic hydroxylamine may each independently be replaced with a derivative capable of undergoing polycondensation.

[0058] For example, by converting the carboxy group to an alkoxycarbonyl group or an aryloxycarbonyl group, aromatic hydroxycarboxylic acids and aromatic dicarboxylic acids can be replaced with aromatic hydroxycarboxylic acid esters and aromatic dicarboxylic acid esters. By converting the carboxy group to a haloformyl group, aromatic hydroxycarboxylic acids and aromatic dicarboxylic acids can be replaced with aromatic hydroxycarboxylic acid halides and aromatic dicarboxylic acid halides. By converting the carboxy group to an acyloxycarbonyl group, aromatic hydroxycarboxylic acids and aromatic dicarboxylic acids can be replaced with aromatic hydroxycarboxylic acid anhydrides and aromatic dicarboxylic acid anhydrides. Examples of polycondensable derivatives of compounds having hydroxy groups, such as aromatic hydroxycarboxylic acids and aromatic hydroxyamines, include those obtained by acylation of the hydroxy group to an acyloxy group (acylated products). For example, by acylation of the hydroxy group to an acyloxy group, aromatic hydroxycarboxylic acids and aromatic hydroxylamines can be replaced with acylated products, respectively. Examples of polycondensable derivatives of aromatic hydroxylamines include those obtained by acylation of the amino group to an acylamino group (acylated products). For example, aromatic hydroxyamines can be replaced with acylated products by acylation of the amino group to convert them into acylamino groups.

[0059] In formula 1, Ar １ is preferably a p-phenylene group, a 2,6-naphthylene group, or a 4,4'-biphenylylene group, and more preferably a 2,6-naphthylene group.

[0060] Ar １ When Ar is a p-phenylene group, unit 1 is, for example, a constitutional unit derived from p-hydroxybenzoic acid. １When Ar is a 2,6-naphthylene group, unit 1 is, for example, a structural unit derived from 6-hydroxy-2-naphthoic acid. １ is a 4,4'-biphenylylene group, unit 1 is, for example, a constitutional unit derived from 4'-hydroxy-4-biphenylcarboxylic acid.

[0061] In formula 2, Ar ２ is preferably a p-phenylene group, an m-phenylene group, or a 2,6-naphthylene group, and more preferably an m-phenylene group.

[0062] Ar ２ When Ar is a p-phenylene group, unit 2 is, for example, a structural unit derived from terephthalic acid. ２ When Ar is an m-phenylene group, unit 2 is, for example, a structural unit derived from isophthalic acid. ２ is a 2,6-naphthylene group, unit 2 is, for example, a structural unit derived from 2,6-naphthalenedicarboxylic acid.

[0063] In formula 3, Ar ３ is preferably a p-phenylene group or a 4,4'-biphenylylene group, and more preferably a p-phenylene group.

[0064] Ar ３ When Ar is a p-phenylene group, unit 3 is, for example, a constitutional unit derived from p-aminophenol. ３ is a 4,4'-biphenylylene group, unit 3 is, for example, a constitutional unit derived from 4-amino-4'-hydroxybiphenyl.

[0065] With respect to the total content of units 1, 2, and 3, the content of units 1 is preferably 30 mol% or more, the content of units 2 is preferably 35 mol% or less, and the content of units 3 is preferably 35 mol% or less. With respect to the total content of units 1, 2, and 3, the content of units 1 is more preferably 30 mol% to 80 mol%, even more preferably 30 mol% to 60 mol%, and particularly preferably 30 mol% to 40 mol%. With respect to the total content of units 1, 2, and 3, the content of units 2 is preferably 10 mol% to 35 mol%, even more preferably 20 mol% to 35 mol%, and particularly preferably 30 mol% to 35 mol%. With respect to the total content of units 1, 2, and 3, the content of units 3 is preferably 10 mol% to 35 mol%, even more preferably 20 mol% to 35 mol%, and particularly preferably 30 mol% to 35 mol%. The total content of each structural unit is the sum of the amounts (moles) of each structural unit, which is calculated by dividing the mass of each structural unit constituting the aromatic polyesteramide by the formula weight of the structural unit.

[0066] The ratio of the content of units 2 to the content of units 3, expressed as [content of units 2] / [content of units 3] (mol / mol), is preferably 0.9 / 1 to 1 / 0.9, more preferably 0.95 / 1 to 1 / 0.95, and even more preferably 0.98 / 1 to 1 / 0.98.

[0067] The aromatic polyesteramide may independently have two or more types of units 1 to 3. The aromatic polyesteramide may also have other structural units in addition to units 1 to 3. The content of other structural units is preferably 10 mol % or less, more preferably 5 mol % or less, based on the total content of all structural units.

[0068] The aromatic polyesteramide is preferably produced by melt-polymerizing raw material monomers corresponding to the structural units that constitute the aromatic polyesteramide.

[0069] The weight average molecular weight of the aromatic polyesteramide is preferably 1,000,000 or less, more preferably 3,000 to 300,000, even more preferably 5,000 to 100,000, and particularly preferably 5,000 to 30,000.

[0070] The dielectric layer may contain one type of resin or two or more types of resins. From the viewpoint of achieving both dielectric properties and mechanical properties, the resin content is preferably 10 to 90% by volume, more preferably 20 to 70% by volume, and even more preferably 30 to 50% by volume.

[0071] The dielectric layer may contain additives other than the inorganic filler and resin, such as a polymerization initiator, a dispersant, a surfactant, a crosslinking agent, and an antioxidant.

[0072] The average thickness of the dielectric layer is not particularly limited, but from the viewpoint of ease of handling, it is preferably 30 μm to 200 mm, more preferably 40 μm to 100 mm, and even more preferably 50 μm to 50 mm.

[0073] The average thickness of the dielectric layer is determined by measuring any five locations using an adhesive film thickness meter, for example, an electronic micrometer (product name "KG3001A", manufactured by Anritsu Corporation), and averaging these values.

[0074] <Method for Producing Dielectric Layer> The method for producing the dielectric layer is not particularly limited, and known methods can be used.

[0075] Suitable film-forming methods include, for example, co-casting, multi-layer coating, and co-extrusion, and the film can also be produced using a dispenser or the like.

[0076] When a multilayer structure is produced by a co-casting method or a multi-layer coating method, it is preferable to carry out the co-casting method or the multi-layer coating method using a solution in which the components of each layer are dissolved or dispersed in a solvent.

[0077] The method for producing the dielectric layer preferably includes a step of preparing a solution by performing a dispersion treatment using a bead mill, and a step of forming a film using the solution.

[0078] Dispersion treatment using a bead mill reduces particle agglomerates and achieves uniformity. The diameter of the beads used in the bead mill is preferably larger than the average particle size of the particles used to prepare the solution. The diameter of the beads is, for example, 0.1 mm to 5 mm.

[0079] Examples of the solvent include halogenated hydrocarbons such as dichloromethane, chloroform, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, 1-chlorobutane, chlorobenzene, and o-dichlorobenzene; halogenated phenols such as p-chlorophenol, pentachlorophenol, and pentafluorophenol; ethers such as diethyl ether, tetrahydrofuran, and 1,4-dioxane; ketones such as acetone and cyclohexanone; esters such as ethyl acetate and γ-butyrolactone; and ethylene carbonate. nitriles such as acetonitrile and succinonitrile; amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone, and urea compounds such as tetramethylurea; nitro compounds such as nitromethane and nitrobenzene; sulfur compounds such as dimethyl sulfoxide and sulfolane; and phosphorus compounds such as hexamethylphosphoramide and tri-n-butylphosphoric acid, and two or more of these may be used.

[0080] As the solvent, a solvent mainly composed of an aprotic compound, particularly an aprotic compound having no halogen atoms, is preferred because it is less corrosive and easier to handle, and the proportion of the aprotic compound in the entire solvent is preferably 50% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, and particularly preferably 90% by mass to 100% by mass. Furthermore, as the aprotic compound, an amide such as N,N-dimethylformamide, N,N-dimethylacetamide, tetramethylurea, N-methylpyrrolidone, or an ester such as γ-butyrolactone is preferably used because it easily dissolves the liquid crystal polymer, and N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone are more preferred.

[0081] Furthermore, as the solvent, a solvent containing as a main component a compound having a dipole moment of 3 to 5 is preferred because it easily dissolves the liquid crystal polymer, and the proportion of the compound having a dipole moment of 3 to 5 in the entire solvent is preferably 50% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, and particularly preferably 90% by mass to 100% by mass. It is preferable to use a compound having a dipole moment of 3 to 5 as the aprotic compound.

[0082] Furthermore, as the solvent, a solvent containing as a main component a compound having a boiling point of 220°C or lower at 1 atmosphere is preferred because it is easy to remove, and the proportion of the compound having a boiling point of 220°C or lower at 1 atmosphere in the entire solvent is preferably 50% by mass to 100% by mass, more preferably 70% by mass to 100% by mass, and particularly preferably 90% by mass to 100% by mass. It is preferable to use a compound having a boiling point of 220°C or lower at 1 atmosphere as the aprotic compound.

[0083] In the method for producing the dielectric layer, when the dielectric layer is produced by the above-mentioned co-casting method, multi-layer coating method, co-extrusion method, or the like, a support may be used.

[0084] Examples of the support include a metal drum, a metal band, a glass plate, a resin film, and a metal foil, and among these, the support is preferably a metal drum, a metal band, or a resin film.

[0085] The support may have a surface treatment layer formed on its surface to facilitate peeling. The surface treatment layer may be made of hard chrome plating, fluororesin, or the like. The average thickness of the support is not particularly limited, but is preferably 25 μm to 75 μm, and more preferably 50 μm to 75 μm.

[0086] The method for removing at least a part of the solvent from the cast or coated film-like composition (coating film) is not particularly limited, and any known drying method can be used.

[0087] <Conductor Layer> The laminate of the present disclosure includes a conductor layer. Two or more types of conductor layers different in size are arranged on one surface of a dielectric layer, and a conductor layer different from the two or more types of conductor layers is arranged on the other surface of the dielectric layer. The two or more types of conductor layers are arranged in the same plane and do not contact each other.

[0088] In the present disclosure, a conductor layer is a layer containing a material having electrical conductivity (a conductive material). ８ It means the property of being less than Ω cm.

[0089] The term "different sizes" means that the sizes are not completely identical, and the size difference may be appropriately selected depending on the signal frequency. The term "two or more types of different sizes" means that the shapes are similar, or that the shapes are different but have different sizes.

[0090] The conductive material preferably contains a metal, more preferably at least one selected from the group consisting of gold, silver, platinum, copper, and aluminum. Among these, from the viewpoints of high conductivity and suppression of ion migration, the conductive material is particularly preferably at least one of gold and copper, and most preferably copper.

[0091] From the viewpoint of high conductivity, the conductor layer preferably has a surface roughness Rc of 1 μm or less on the dielectric layer side, more preferably 0.7 μm or less. From the viewpoint of improving adhesion to the dielectric, the lower limit of the surface roughness Rc is preferably 0.01 μm.

[0092] In the present disclosure, the surface roughness Rc is measured by the following method. The laminate is cut with a microtome to expose a cross section. The average height Rc of the interface between the conductor layer and the dielectric layer is measured in accordance with JIS B0601 2001. The evaluation length is 500 μm.

[0093] Hereinafter, with reference to FIG. 1, two or more types of conductor layers of different sizes arranged on one surface of a dielectric layer will be described.

[0094] FIG. 1 is a schematic plan view showing the arrangement of conductor layers in a laminate according to the present disclosure.

[0095] As shown in FIG. 1, in the laminate 100, a plurality of conductor layers 12A and 12B having different sizes are disposed on a dielectric layer 11.

[0096] The conductor layers 12A and 12B preferably have different signal frequencies.

[0097] The size of the conductor layer 12A is smaller than the size of the conductor layer 12B, and the conductor layer 12A is adapted to radio waves with a higher frequency than the conductor layer 12B.

[0098] The planar shapes of the conductor layers 12A and 12B are not particularly limited, and may be quadrangular (e.g., square, rectangular, etc.) as shown in FIG. 1 or may be circular. The conductor layers 12A and 12B may have different sizes, and may have the same or different shapes in plan view. When the conductor layers are square, the length of one side is, for example, 0.2 mm to 130 mm. For example, the conductor layer 12A is a square with a side of 1.3 mm in plan view, and the conductor layer 12B is a square with a side of 2.8 mm in plan view.

[0099] The conductor layers 12A and 12B are arranged in the same plane and not in contact with each other.

[0100] The conductor layers 12A are preferably arranged in a grid pattern at approximately equal intervals. Similarly, the conductor layers 12B are preferably arranged in a grid pattern at approximately equal intervals. "Arranged at approximately equal intervals" means that the plurality of conductor layers are regularly arranged at equal intervals or at equal intervals within an error of ±20%.

[0101] The distance between adjacent conductor layers is, for example, 5 mm to 360 mm. For example, the distance between adjacent conductor layers 12A is 10 mm, and the distance between adjacent conductor layers 12B is 21 mm. The distance between adjacent conductor layers means the distance between the centers of the conductor layers. The distance between adjacent conductor layers is adjusted appropriately depending on the corresponding frequency.

[0102] In particular, from the viewpoint of avoiding contact between the conductor layers, it is preferable that the conductor layers 12A and 12B be arranged in a staggered pattern.

[0103] A staggered arrangement can be determined by the following method. Lines are drawn between conductor layers (e.g., conductor layer 12A) to draw grid lines A. Lines are drawn between other conductor layers (e.g., conductor layer 12B) to draw grid lines B. If grid lines A and B do not overlap in the same axial direction, it is determined that the conductor layers are staggered. Note that if a portion of the grid pattern is missing when grid lines are drawn between conductor layers, it is not determined that the conductor layers are staggered.

[0104] In the laminate of the present disclosure, a conductor layer different from the two or more types of conductor layers is disposed on the other surface of the dielectric layer, and this conductor layer functions as a ground layer.

[0105] [Antenna Substrate] The antenna substrate of the present disclosure includes the laminate. A pattern antenna can be fabricated from the laminate by a known method such as photofabrication. The frequency response of the antenna can be appropriately adjusted by designing the pattern, patch size, etc.

[0106] [Antenna Module] The antenna module of the present disclosure is, in one aspect, an antenna module including an antenna substrate and configured to transmit and receive radio waves having a frequency of 6 GHz to 24 GHz. In another aspect, the antenna module of the present disclosure is, in another aspect, an antenna module including an antenna substrate and configured to transmit and receive radio waves having a frequency of 0.5 GHz to 5.9 GHz.

[0107] The present disclosure will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present disclosure. Therefore, the scope of the present disclosure is not limited to the specific examples shown below.

[0108] Details of the materials used in producing the laminate are as follows.

[0109] <Inorganic fillers> F1: Pulverized barium titanate particles (average particle size 2 μm, relative dielectric constant 1,000, dielectric dissipation factor 0.015) F2: Pulverized titanium dioxide particles (average particle size 7 μm, relative dielectric constant 85, dielectric dissipation factor 0.013) F3: Pulverized strontium titanate particles (average particle size 1 μm, relative dielectric constant 300, dielectric dissipation factor 0.005) F4: Pulverized barium titanate particles (average particle size 4 μm, relative dielectric constant 2,000, dielectric dissipation factor 0.100)

[0110] <Resins> P1: Aromatic polyesteramide prepared according to the following production method. P2: A mixture (mass ratio 100:5) of aromatic polyesteramide prepared according to the following production method and aminophenol-type epoxy resin (product name "jER630", manufactured by Mitsubishi Chemical Corporation). P3: Cycloolefin polymer (product name "ZEONEX480R", manufactured by Zeon Corporation).

[0111] -Synthesis of aromatic polyesteramide P1- A reactor equipped with a stirrer, torque meter, nitrogen gas inlet tube, thermometer, and reflux condenser was charged with 940.9 g (5.0 mol) of 6-hydroxy-2-naphthoic acid, 415.3 g (2.5 mol) of isophthalic acid, 377.9 g (2.5 mol) of acetaminophen, and 867.8 g (8.4 mol) of acetic anhydride. The gas inside the reactor was replaced with nitrogen gas, and then the mixture was heated from room temperature (23°C, the same applies hereinafter) to 140°C over 60 minutes while stirring under a nitrogen gas stream, and refluxed at 140°C for 3 hours. Next, while distilling off by-product acetic acid and unreacted acetic anhydride, the mixture was heated from 150°C to 300°C over 5 hours and held at 300°C for 30 minutes. The contents were then removed from the reactor and cooled to room temperature. The resulting solid was pulverized in a grinder to obtain powdered aromatic polyesteramide P1a. The flow initiation temperature of the aromatic polyesteramide P1a was 193°C. The aromatic polyesteramide P1a was a wholly aromatic polyesteramide. The aromatic polyesteramide P1a was heated from room temperature to 160°C over 2 hours and 20 minutes under a nitrogen atmosphere, then heated from 160°C to 180°C over 3 hours and 20 minutes, and held at 180°C for 5 hours to undergo solid-state polymerization, followed by cooling. The mixture was then pulverized in a grinder to obtain a powdered aromatic polyesteramide P1b. The flow initiation temperature of the aromatic polyesteramide P1b was 220°C. The aromatic polyesteramide P1b was heated from room temperature to 180°C over 1 hour and 25 minutes under a nitrogen atmosphere, then heated from 180°C to 255°C over 6 hours and 40 minutes, and held at 255°C for 5 hours to undergo solid-state polymerization, followed by cooling to obtain a powdered aromatic polyesteramide P1. The flow initiation temperature of the aromatic polyesteramide P1 was 302°C. The melting point of the aromatic polyesteramide P1 was measured using a differential scanning calorimeter and found to be 311° C. The dielectric dissipation factor of the aromatic polyesteramide P1 was 0.003.

[0112] <Copper foil> M1: Product name "CF-T49A-DS-HD2", manufactured by Fukuda Metal Foil & Powder Co., Ltd., average thickness 18 μm, surface roughness Rc: 1.0 μm

[0113] M2: Product name "CF-T9DA-SV", manufactured by Fukuda Metal Foil & Powder Co., Ltd., average thickness 18 μm, surface roughness Rc: 0.7 μm

[0114] <Film> (Film for Comparative Example 2) Using a known melt extrusion method, P3 was molded into a sheet having a thickness of 600 μm to prepare a film for Comparative Example 2.

[0115] (Film for Comparative Example 4) P4: Prepreg made of FR-4 material with a thickness of 109 μm (product name "R-1661", manufactured by Panasonic Industries Co., Ltd.)

[0116] <Double-sided copper-clad laminate> T1: 0.6 mm thick double-sided copper-clad laminate made of FR-4 material (product name "R-1766", manufactured by Panasonic Industries Co., Ltd.)

[0117] [Preparation of Laminate] Example 1 (Film Formation 1) The inorganic filler and resin shown in Table 1 were mixed in the contents (mass %) shown in Table 1 and dispersed in a bead mill to obtain a solution (dispersion).

[0118] The resulting solution was sent to a slot die and applied to the copper foil shown in Table 1, adjusting the flow rate so that the average thickness after drying would be 60 μm. The solvent was removed from the coating by hot air drying to obtain a polymer film (single-sided copper-clad laminate) having a copper layer. Further, a single-sided copper-clad laminate was produced by heating from 50° C. to 300° C. at a rate of 1° C. / min in a nitrogen atmosphere and maintaining the temperature at 300° C. for 2 hours.

[0119] (Film Formation 2) The copper foil of the single-sided copper-clad laminate obtained in Film Formation 1 was removed with an aqueous solution of ferric chloride, washed with pure water, and then dried to prepare a film.

[0120] (Preparation of double-sided copper-clad laminate) The single-sided copper-clad laminate obtained in film production 1 and the film obtained in film production 2 were laminated in the order of single-sided copper-clad laminate of film production 1 / film of film production 2 / single-sided copper-clad laminate of film production 1, with the copper foil being the outermost surface. At this time, the number of films of film production 2 was adjusted so that the thickness of the dielectric layer was 600 μm. Using a laminator (product name "Vacuum Laminator V-130", manufactured by Nikko Materials Co., Ltd.), a lamination process was performed for 1 minute under conditions of 140 ° C. and a lamination pressure of 0.4 MPa to obtain a precursor of a double-sided copper-clad laminate. Furthermore, using a thermocompression bonding machine (product name "MP-SNL", manufactured by Toyo Seiki Seisakusho Co., Ltd.), the obtained precursor of the double-sided copper-clad laminate was thermocompressed at 320 ° C. to produce a double-sided copper-clad laminate.

[0121] (Laminate Fabrication) Subsequently, the copper foil on one side of the double-sided copper-clad laminate was patterned using a known subtraction method. Conductor layer 1 was arranged as a square microstrip antenna designed for a resonant frequency of 15 GHz. Conductor layer 2 was arranged as a square microstrip antenna designed for a resonant frequency of 7 GHz. The sizes of conductor layer 1 and conductor layer 2, the distance between conductor layer 1, and the distance between conductor layer 2 were adjusted as shown in Table 1. As shown in FIG. 1 , a laminate was fabricated in which conductor layer 1 with 4 × 4 patches and conductor layer 2 with 2 × 2 patches were arranged in a staggered pattern.

[0122] - Example 2 - In Example 2, a laminate was produced in the same manner as in Example 1, except that the distance between the conductor layers 2 was changed, and a conductor layer 1 with a patch count of 4 × 4 and a conductor layer 2 with a patch count of 2 × 2 were arranged as shown in Figure 2.

[0123] -Examples 3 to 5- In Examples 3 to 5, laminates were produced in the same manner as in Example 2, except that the type or content of the inorganic filler and resin, or the type of copper foil, and the sizes of conductor layer 1 and conductor layer 2 were changed.

[0124] Example 6 In Example 6, a laminate was produced in the same manner as in Example 1, except that the positions of conductor layer 1 and conductor layer 2 were changed. Specifically, as shown in Fig. 3, a laminate was produced in which conductor layer 1 with 15 patches and conductor layer 2 with 4 patches were arranged.

[0125] Examples 7 to 9 In Examples 7 to 9, laminates were produced in the same manner as in Example 2, except that the type and content of the inorganic filler and the sizes of the conductor layer 1 and the conductor layer 2 were changed, and the thickness of the dielectric layer was changed to 1,800 μm.

[0126] Comparative Example 1 A laminate was produced in the same manner as in Example 1, except that the double-sided copper-clad laminate T1 was used and the sizes of conductor layer 1 and conductor layer 2 were changed. Conductor layer 1 and conductor layer 2 were partially in contact with each other and bonded.

[0127] Comparative Example 2 (Preparation of Double-Sided Copper-Clad Laminate) The film for Comparative Example 2 was sandwiched between a pair of copper foils listed in Table 1, and a lamination process was performed for 1 minute using a laminator (product name "Vacuum Laminator V-130", manufactured by Nikko Materials Co., Ltd.) at 140°C and a lamination pressure of 0.4 MPa, to obtain a precursor of a double-sided copper-clad laminate. Furthermore, a thermocompression bonding machine (product name "MP-SNL", manufactured by Toyo Seiki Seisakusho, Ltd.) was used to thermocompress the obtained precursor of the double-sided copper-clad laminate at 200°C to produce a double-sided copper-clad laminate. A laminate was produced in the same manner as in Example 1, except that the obtained double-sided copper-clad laminate was used.

[0128] Comparative Example 3 A laminate was produced in the same manner as in Example 1, except that the sizes of conductor layer 1 and conductor layer 2 were changed. Conductor layer 1 and conductor layer 2 were partially in contact with each other and bonded together.

[0129] Comparative Example 4: Using a double-sided copper-clad laminate T1, the copper foil on one side was patterned using a known subtraction method, and a conductor layer 1 was arranged as a square microstrip antenna designed for a resonant frequency of 7 GHz. Using another double-sided copper-clad laminate T1, the copper foil on one side was removed with an aqueous solution of ferric chloride, and the copper foil on the other side was patterned using a known subtraction method, and a conductor layer 2 was arranged as a square microstrip antenna designed for a resonant frequency of 15 GHz. The surface on which conductor layer 1 was arranged and the back surface of conductor layer 2 were laminated via P4, and heated at 170°C and 2.94 MPa for 90 minutes to produce a laminate. Conductor layer 1 and conductor layer 2 were arranged so that the centers of the conductor layers were aligned in the in-plane direction.

[0130] <<Evaluation>> The produced laminates were subjected to the following measurements and evaluations.

[0131] <<Measurement Method>> [Dielectric Properties] The copper foil of a double-sided copper-clad laminate was removed with an aqueous solution of ferric chloride, washed with pure water, and dried to obtain a film. The dielectric constant and dielectric loss tangent were measured using a resonance perturbation method at a frequency of 10 GHz. A 10 GHz cavity resonator (Kanto Electronics Application Development Co., Ltd., CP531) was connected to a network analyzer (Agilent Technology, Inc., E8363B). The film was inserted into the cavity resonator, and the dielectric constant and dielectric loss tangent of the film (dielectric layer) were measured from the change in resonance frequency before and after insertion for 96 hours under an environment of 25°C and 60% RH.

[0132] [Radiation Characteristics] The laminate was used as a rectangular microstrip antenna, and the radiation angle and radiation efficiency (total radiated power ÷ input power) were measured as radiation characteristics at 7 GHz and 15 GHz, and evaluated according to the following criteria. <Evaluation criteria for radiation angle> A: The radiation angle is 40% or less of that of a single patch (1 x 1), indicating high directivity. B: The radiation angle is more than 40% but not more than 60% of that of a single patch, indicating sufficient directivity. C: The radiation angle is more than 60% but not more than 80% of that of a single patch, indicating low directivity. D: No directivity was observed <Evaluation criteria for radiation efficiency> A: The radiation efficiency was -1 dB or more. B: The radiation efficiency was -2 dB or more but less than -1 dB. C: The radiation efficiency was -3 dB or more but less than -2 dB. D: The radiation efficiency was less than -3 dB.

[0133] The measurement results and evaluation results are shown in Table 1. In Table 1, "size" refers to the length of one side of a conductor layer that is square in plan view. "Spacing" refers to the distance between the conductor layers. Furthermore, if the condition that conductor layer 1 and conductor layer 2 are arranged in the same plane and are not in contact with each other is met, "Y" is entered in the "In-plane / non-contact" column, and if this condition is not met, "N" is entered. Furthermore, if the above condition is met, it was determined whether conductor layer 1 and conductor layer 2 are arranged in a staggered pattern. If conductor layer 1 and conductor layer 2 are arranged in a staggered pattern, "Y" is entered, and if conductor layer 1 and conductor layer 2 are not arranged in a staggered pattern, "N" is entered.

[0134]

[0135] From Table 1, it was found that Examples 1 to 9 include a dielectric layer having a relative dielectric constant of more than 3 and a conductor layer, two types of conductor layers having different sizes are arranged on one side of the dielectric layer, and a conductor layer different from the two types of conductor layers is arranged on the other side of the dielectric layer, and the two types of conductor layers are arranged in the same plane and so as not to contact each other, and therefore can handle high-frequency band signals.

[0136] On the other hand, in Comparative Examples 1 and 3, the two types of conductor layers were partially in contact with each other, and it was found that the radiation characteristics were poor. In Comparative Example 2, the relative permittivity of the dielectric layer was less than 3, and it was found that the radiation characteristics were poor. In Comparative Example 4, the two types of conductor layers were not in the same plane, and it was found that the radiation characteristics were poor.

[0137] The disclosure of Japanese Patent Application No. 2023-150291, filed on September 15, 2023, is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference.

Claims

1. A laminate comprising a dielectric layer having a relative dielectric constant of greater than 3 and a conductor layer, wherein two or more types of conductor layers different in size are arranged on one surface of the dielectric layer, and a conductor layer different from the two or more types of conductor layers is arranged on the other surface of the dielectric layer, wherein the two or more types of conductor layers are arranged within the same plane and are not in contact with each other.

2. The laminate according to claim 1, wherein the dielectric layer satisfies the following formula A, where T is the relative dielectric constant and D is the dielectric loss tangent. ０．５ ×D≦0.10… Formula A 3. The laminate according to claim 1 or 2, wherein the two or more types of conductor layers are arranged in a staggered pattern.

4. The laminate according to claim 1 or 2, wherein the dielectric layer has a dielectric loss tangent of less than 0.

01.

5. The laminate according to claim 1 or 2, wherein the dielectric layer contains an inorganic filler and a resin.

6. The laminate according to claim 5, wherein the inorganic filler has a relative dielectric constant of 6 to 20,000.

7. The laminate according to claim 5, wherein the inorganic filler comprises at least one selected from the group consisting of barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, zirconium titanate, zinc titanate, titanium dioxide, magnesium oxide, alumina, tantalum pentoxide, and niobium pentoxide.

8. The laminate described in claim 5, wherein in the dielectric layer, the ratio (Do / Di) of the number of the inorganic filler particles per unit area in an in-plane direction (Di) to the number of the inorganic filler particles per unit area in a thickness direction (Do) is 0.5 or more.

9. The laminate according to claim 5, wherein the resin comprises at least one selected from the group consisting of a thermoplastic resin, a thermoplastic elastomer, a semi-cured product of a thermosetting resin, a cured product of a thermosetting resin, a semi-cured product of a thermosetting elastomer, and a cured product of a thermosetting elastomer.

10. A laminate according to claim 1 or 2, wherein the conductor layer has a surface roughness Rc of 1 μm or less on the dielectric layer side.

11. The laminate according to claim 1 or 2, wherein the two or more types of conductor layers have mutually different signal frequencies.

12. An antenna substrate comprising the laminate according to claim 1 or 2.

13. An antenna module for transmitting and receiving radio waves having a frequency of 6 GHz to 24 GHz, comprising the antenna board according to claim 12.

14. An antenna module for transmitting and receiving radio waves having a frequency of 0.5 GHz to 5.9 GHz, comprising the antenna board according to claim 12.

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