Glass plate structure, vibration plate and opening member

Abstract

The present invention relates to a glass plate assembly, which includes two or more plates. An intermediate layer is included between at least a pair of the plates. The intermediate layer satisfies all of the following properties (1) to (3). At least one of the pair of plates is a glass plate, having a loss factor of 0.01 or more at 25°C, and a longitudinal wave sound velocity value in the plate thickness direction of 4.0×10<supgt;3< / supgt> m / s or more. (1) The thickness is 20 μm or less. (2) The compression storage elastic modulus at a temperature of 25°C is 1.0×10<supgt;4< / supgt> Pa or less. (3) At a temperature of 25°C and 1 Hz, the compression storage elastic modulus is higher than the compression loss elastic modulus.

Description

Technical Field

[0001] The present invention relates to a glass plate structure having good acoustic performance, and also to a vibration plate and an opening member using the glass plate structure. Background Art

[0002] Generally speaking, drum paper or resin is used as a vibration plate for speakers or microphones. These materials have a large loss coefficient and are difficult to resonate, so they have good performance in reproducing sounds within the audible threshold.

[0003] However, these materials have low sound velocity values, so when driven at high frequencies, the vibration of the material is difficult to follow and split vibration is easily generated. Therefore, it is difficult to generate the desired sound pressure, especially in the high-frequency region. As mentioned above, it is not suitable for use as a large-area vibration plate.

[0004] In recent years, the frequency band that is particularly required to reproduce high-resolution sound sources is the high-frequency region above 20kHz, which is a frequency band that cannot be heard by the human ear, but it is said that it can make the emotions more realistic, such as making the sense of presence stronger, etc. Therefore, it is expected to reproduce the sound wave vibrations in this frequency band faithfully.

[0005] Therefore, it is considered to use materials with high sound velocity in materials such as metal, ceramics, and glass instead of drum paper and resin. However, in general, the loss coefficient of these materials is very small compared to paper, about 1 / 10 to 1 / 100, and it is easy for undesired reverberation to remain. Furthermore, when the components are driven at their natural frequency, the sound quality is likely to deteriorate significantly due to the generation of resonance modes.

[0006] Here, as a diaphragm for a speaker, a laminated glass having a polyvinyl butyral polymer between two glass plates is known (Non-Patent Document 1).

[0007] Prior art literature

[0008] Non-patent literature

[0009] Non-patent document 1: Olivier Mal et al., "A Novel Glass Laminated Structure for Flat Panel Loudspeakers" AES Convention 124, 7343 Summary of the invention

[0010] The diaphragm described in Non-Patent Document 1 aims to reproduce smooth sound by attenuating the vibration, particularly resonance, of the glass using the attenuation characteristics of a layer (intermediate layer) between two glass plates.

[0011] However, the peak at which the attenuation characteristics of the intermediate layer are maximized is usually one, while there are multiple resonance points of the glass. Therefore, it is impossible to attenuate all resonances, or frequencies other than the resonance frequency may also be attenuated. In addition, in the case of laminated glass using polyvinyl butyral polymers as described in Non-Patent Document 1, the loss coefficient of polyvinyl butyral polymers varies depending on the frequency, so that areas with large attenuation and areas with small attenuation are generated in the audible frequency region. As described above, there is a problem that it is difficult to achieve smooth sound reproduction in a wide frequency band.

[0012] In addition, if the glass plate becomes thicker and heavier, the required vibration damping force also becomes larger. Therefore, it is necessary to improve the vibration damping ability of the intermediate layer material or to increase the film thickness to improve the vibration damping ability. However, there is a limit to improving the vibration damping ability while maintaining the solid state, and there is a problem that the longitudinal wave speed decreases if the film thickness is increased.

[0013] Therefore, in order to solve the above-mentioned problems, an object of the present invention is to provide a glass plate structure having good acoustic performance.

[0014] The inventors of the present invention have conducted intensive studies and have found that smooth frequency response characteristics can be obtained by providing a predetermined intermediate layer between a predetermined pair of plates in a glass plate structure, thereby completing the present invention. That is, the present invention is as follows.

[0015] [1] A glass plate structure comprising two or more plates, wherein at least one pair of the plates comprises an intermediate layer between the plates;

[0016] At least one of the pair of plates is a glass plate,

[0017] The above-mentioned intermediate layer satisfies all of the following characteristics (1) to (3),

[0018] The glass sheet structure has a loss factor of 0.01 or more at 25°C and a longitudinal wave velocity value in the sheet thickness direction of 4.0×10 3 m / s or more.

[0019] (1) The thickness of the intermediate layer is 20 μm or less,

[0020] (2) The compression storage elastic modulus at 25°C is 1.0×10 4 Below Pa,

[0021] (3) At 25°C and 1 Hz, the compression storage modulus is higher than the compression loss modulus.

[0022] [2] The glass plate structure according to [1], wherein all of the pair of plates are glass plates,

[0023] The glass sheet structure has a loss factor of 0.01 or more at 25°C and a longitudinal wave velocity value of 5.0×10 3 m / s or more.

[0024] [3] The glass sheet structure according to [1] or [2], wherein the total thickness of the pair of sheets is 1.0 mm or more,

[0025] The intermediate layer and the plate satisfy the following formula A.

[0026]

[0027] [4] The glass sheet structure according to any one of [1] to [3], wherein the average Young's modulus of the pair of sheets at 25° C. is 20 GPa or more.

[0028] [5] The glass sheet structure according to any one of [1] to [4], wherein the product of the total thickness of the pair of sheets and the average Young's modulus of the pair of sheets is 2.0×10 7 Pa·m and above.

[0029] [6] The glass sheet structure according to any one of [1] to [5], wherein a value obtained by dividing the thickness of the intermediate layer by the total thickness of the pair of sheets is 0.02 or less.

[0030] [7] The glass sheet structure according to any one of [1] to [6], wherein the value of the compressive storage elastic modulus of the intermediate layer material divided by the average Young's modulus of the pair of sheets is 1×10 4 the following.

[0031] [8] The glass sheet structure according to any one of [1] to [7], wherein the value obtained by dividing the mass of the sheet A on one side of the pair of sheets by the mass of the sheet B on the other side of the pair of sheets is 0.8 to 1.25.

[0032] [9] The glass sheet structure according to any one of [1] to [8], wherein the loss coefficient of at least one of the pair of sheets at 25°C is 1×10 －4 above.

[0033]

[10] The glass sheet structure according to any one of [1] to [9], wherein the longitudinal wave sound velocity value in the sheet thickness direction of at least one sheet of the pair of sheets is 4.0×10 3 m / s or more.

[0034]

[11] The glass sheet structure according to any one of [1] to

[10] , wherein a sliding layer is provided on the surface of the pair of sheets in contact with the intermediate layer.

[0035]

[12] The glass plate structure according to any one of [1] to

[11] , wherein the specific gravity of the glass plate is 2.8 or less.

[0036]

[13] The glass sheet structure according to any one of [1] to

[12] , wherein the specific elastic modulus of the glass sheet is 2.5×10 7 m 2 / s 2 above.

[0037]

[14] The glass plate structure according to any one of [1] to

[13] , wherein the difference between the refractive index of the intermediate layer and the refractive index of the pair of plates in contact with the intermediate layer is 0.3 or less.

[0038]

[15] The glass sheet structure according to any one of [1] to

[14] , wherein the glass sheet structure has a curved shape.

[0039]

[16] A vibration plate comprising: the glass plate structure according to any one of [1] to

[15] , and at least one vibrator provided on one or both surfaces of the glass plate structure.

[0040]

[17] An opening component using the glass plate structure described in any one of [1] to

[15] or the vibration plate described in

[16] .

[0041] According to the present invention, a glass sheet structure including a predetermined intermediate layer between a predetermined pair of sheets can effectively suppress peaks and valleys from resonance, and can obtain smooth frequency response characteristics as a glass sheet structure.

[0042] Therefore, according to the present invention, when the vibrator is installed as a diaphragm of a speaker, or used for active noise reduction or echo suppression, since it is a structure that can suppress the resonance of the component, smooth sound reproduction and sound control can be achieved. Furthermore, due to the high vibration attenuation ability, it is also possible to suppress the noise generated by resonance and the sound transmitted from the noise source. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a cross-sectional view of the glass sheet structure according to the first embodiment of the present invention.

[0044] Figure 2 This is a cross-sectional view of a glass sheet structure according to another embodiment of the present invention.

[0045] Figure 3 This is a cross-sectional view of a glass sheet structure according to another embodiment of the present invention.

[0046] Figure 4 2 is a diagram showing a glass plate structure according to another embodiment of the present invention. Figure 4 (a) is a plan view of the glass plate structure, Figure 4 (b) is Figure 4 (a) is the cross-sectional view along the line AA'.

[0047] Figure 5 2 is a diagram showing a glass plate structure according to another embodiment of the present invention. Figure 5 (a) is a plan view of the glass plate structure, Figure 5 (b) is Figure 5 (a) is the cross-sectional view along the line AA'.

[0048] Figure 6 2 is a diagram showing a glass plate structure according to another embodiment of the present invention. Figure 6 (a) is a plan view of the glass plate structure, Figure 6 (b) is Figure 6 The cross-sectional view along line I-I in (a) is as follows: Figure 6 (c) is Figure 6 An enlarged view of part C in (b).

[0049] Figure 7 2 is a diagram showing a glass plate structure according to another embodiment of the present invention. Figure 7 (a) is a plan view of the glass plate structure, Figure 7 (b) is Figure 7 (a) is the cross-sectional view along line I-I. DETAILED DESCRIPTION

[0050] Hereinafter, the details and other features of the present invention will be described based on the mode for carrying out the invention.

[0051] It should be noted that in the following drawings, the same or corresponding components or parts are given the same or corresponding symbols, and repeated descriptions are omitted. In addition, unless otherwise specified, the drawings are not intended to show the mutual comparison between components or parts. Therefore, specific dimensions can be appropriately selected with reference to the following non-limiting embodiments.

[0052] In addition, in this specification, when "to" which shows a numerical range is used, it means that the numerical value described before and after it is included as a lower limit and an upper limit.

[0053] <Glass plate structure>

[0054] The glass plate structure of the present invention comprises at least two plates and an intermediate layer provided between the two plates, at least one of the two plates is a glass plate, and the intermediate layer contains a substance satisfying specific properties.

[0055] In the glass plate structure according to the present invention, when one plate resonates, the presence of the intermediate layer can prevent the other plate from resonating or attenuate the vibration of the resonance of the other plate, thereby obtaining a smoother frequency response characteristic compared to the case of a single glass plate.

[0056] When the glass plate structure of the present invention is used as a glass vibration plate, the higher the sound velocity value, the higher the reproducibility of the sound in the high frequency region, and thus it is preferably used as a vibration plate. Specifically, the sound velocity value of the longitudinal wave in the plate thickness direction at 25°C is 4.0×10 3 m / s or more, preferably 4.5×10 3 m / s or more, more preferably 5.0×10 3 m / s or more, particularly preferably 5.5×10 3 m / s or more, and the upper limit is not particularly limited.

[0057] The longitudinal wave sound velocity value refers to the speed at which longitudinal waves propagate in the vibration plate. The longitudinal wave sound velocity value and Young's modulus can be measured according to the ultrasonic pulse method described in Japanese Industrial Standards (JIS-R1602-1995).

[0058] When the glass plate structure of the present invention is used as a glass vibration plate, the larger the loss coefficient, the greater the vibration attenuation of the plate structure, and it is preferably used as a vibration plate. Specifically, the loss coefficient at 25°C is 0.01 or more, preferably 0.05 or more, more preferably 0.1 or more, more preferably 0.2 or more, particularly preferably 0.3 or more, and most preferably 0.4 or more, and the upper limit is not particularly limited.

[0059] The loss factor is a value calculated using the half-width method. When the resonance frequency of the material is f and the frequency width at the point where the amplitude h drops by -3 dB (i.e., the point where the maximum amplitude is -3 [dB]) is W, the value represented by {W / f} is defined as the loss factor.

[0060] In order to suppress resonance, the loss factor may be increased, that is, the frequency width W may be relatively increased relative to the amplitude h, which means that the peak may be broadened.

[0061] (Middle layer)

[0062] Among the materials constituting the intermediate layer, preferred materials are those satisfying all of the following characteristics (1) to (3).

[0063] (1) The thickness of the intermediate layer is 20 μm or less,

[0064] (2) The compression storage elastic modulus at 25°C is 1.0×10 4 Below Pa,

[0065] (3) At 25°C and 1 Hz, the compression storage modulus is higher than the compression loss modulus.

[0066] In the case of laminated glass using the dynamic viscoelastic mechanism of the existing intermediate layer material, the loss coefficient of the glass plate structure is improved due to the dynamic viscoelasticity of the intermediate layer material. Therefore, as the thickness of the plate increases, in order to obtain a high loss coefficient, the intermediate layer also needs to be thicker.

[0067] The present invention has found that by satisfying characteristics (1), (2), and (3), the fluidity of the intermediate layer is suppressed and the loss coefficient is improved. Generally speaking, when the loss coefficient of the glass plate structure is improved by increasing the thickness of the intermediate layer, the sound velocity value of the glass plate structure decreases as the thickness of the intermediate layer increases, and there is a trade-off relationship. In contrast, in the present structure, by making the material of the intermediate layer satisfy characteristic (2), when the intermediate layer is thin, not only can the loss coefficient of the glass plate structure be further increased, but a high sound velocity value can also be ensured.

[0068] Regarding characteristic (1), the thickness of the intermediate layer is 20 μm or less, preferably 10 μm or less, more preferably 8 μm or less, and particularly preferably 5 μm or less, from the viewpoint of obtaining a high loss factor of the glass sheet structure. In addition, from the viewpoint of the surface roughness of the sheet, it is preferably 0.1 μm or more.

[0069] In addition, when the plates are not in contact with each other and the plates in the unpolished state are preferably used, the thickness of the intermediate layer is preferably greater than the surface roughness. In the case where the surface roughness of the two plates is different, it is preferably greater than the surface roughness of the one with the larger roughness. In addition, in the plate to which the surface is polished, the surface roughness is very small, so it is sufficient to be at least greater than the surface roughness.

[0070] Regarding characteristic (2), the compressive storage elastic modulus of the material of the intermediate layer at a temperature of 25°C is 1.0×10 4 Pa or less, preferably 7.0×10 3 Pa or less, more preferably 5.0×10 3 Pa or less. If the material satisfies characteristic (2), the thinner the thickness of the intermediate layer, the higher the loss factor can be obtained in the glass sheet structure. In addition, from the viewpoint of fluidity, it is preferably 1.0×10 2 Pa or above.

[0071] Characteristic (3) means that the fluidity of the intermediate layer material is low, that is, the intermediate layer material is not liquid. By satisfying characteristic (3), the fluidity of the intermediate layer can be suppressed, so that the glass plate structure can be easily cut at will. The intermediate layer material is preferably a gel-like material.

[0072] In addition, the intermediate layer and the plate preferably satisfy the following formula A.

[0073]

[0074] The right side of formula A is 1.0×10 －10 Below, more preferably 7.5×10 －11 Below, more preferably 5.0×10 －11 Below, more preferably 1.0×10 －12 Below, particularly preferably 5.0×10 －13 the following.

[0075] Formula A means that the thickness and elastic modulus (Young's modulus) of the intermediate layer and the plate satisfy a specific relationship.

[0076] In Formula A, both "thickness of the intermediate layer / total thickness of a pair of plates" and "compression storage elastic modulus of the intermediate layer material / average Young's modulus of two plates" are preferably smaller.

[0077] Regarding the thickness of the intermediate layer and the total thickness of the pair of plates, when the glass plate structure of the present invention is used as an opening part such as a window, the thickness of the intermediate layer is preferably thinner from the viewpoint of increasing the loss coefficient of the glass plate structure, and the thickness of the plate is preferably thicker from the viewpoint of safety. The thinner the thickness of the intermediate layer, the more preferred, which is consistent with the above-mentioned characteristic (1). Regarding the thickness of the plate, specifically, the total thickness of the pair of plates is preferably 1.0 mm or more, and more preferably greater than 1.0 mm.

[0078] Regarding the compression storage elastic modulus of the intermediate layer material and the average Young's modulus of a pair of plates, from the perspective of applicability to parts requiring a large area such as opening parts, warping will be reduced when the plate thickness is thick and the Young's modulus of the plate is high, which is preferred.

[0079] Here, the average Young's modulus of the pair of plates at 25° C. is at least 20 GPa or more, more preferably 60 GPa or more, and even more preferably 70 GPa or more.

[0080] Furthermore, it is necessary to consider both the thickness of the pair of plates and the preferred range of the average Young's modulus of the pair of plates, and it is preferred to increase "the total thickness of the pair of plates × the average Young's modulus of the pair of plates". Specifically, it is preferably 2.0 × 10 7 Pa·m or more, more preferably 6.0×10 7 Pa·m or more, more preferably 1.0×10 8 Pa·m and above.

[0081] In addition, as shown in characteristic (2), the compressive storage elastic modulus of the intermediate layer material is 1.0×10 4Pa or less, so if the interlayer becomes thicker, the Young's modulus of the glass plate structure will be greatly reduced, which is not preferred. On the other hand, when the thickness of the interlayer is sufficiently thin relative to the total thickness of a pair of plates, the influence of the interlayer material on the Young's modulus of the glass plate structure is reduced, which is preferred. Specifically, "the thickness of the interlayer / the total thickness of a pair of plates" is preferably 0.02 or less, more preferably 0.01 or less, and further preferably 0.005 or less.

[0082] In addition, if the elastic component of the intermediate layer increases, that is, the compression storage elastic modulus increases, even if the intermediate layer is made thinner, the elasticity of the intermediate layer material relative to the Young's modulus of the plate and the vibration of the glass cannot be ignored, and the loss factor cannot be increased. Specifically, in order to reduce the contribution of the elastic component in the dynamic viscoelasticity of the intermediate layer material, "compression storage elastic modulus of the intermediate layer material / average Young's modulus of two sheets of glass" is preferably 1×10 4 Below, more preferably 5.0×10 3 Below, more preferably 1×10 3 the following.

[0083] As the material constituting the intermediate layer, on the premise of satisfying the above-mentioned characteristics (1) to (3), for example, carbon-based, fluorine-based, or silicone-based polymer materials can be cited. Specifically, ABS, AES, AS, CA, CN, CPE, EEA, EVA, EVOH, IO, PMMA, PMP, PP, PS, PVC, RB, TPA, TPE, TPEE, TPF, TPO, TPS, TPU, TPVC, AAS, ACS, PET, PPE, PA6, PA66, PBN, PBT, PC, POM, PPO, ETFE, FEP, LCP, PEEK, PEI, PES, PFA, PPS, PSV, PTFE, PVDF, silicone, polyurethane, PI, PF, etc. can be cited. Alternatively, composite materials combining the above materials can be cited. The above materials can be used alone or in combination of two or more.

[0084] The proportion of the substance satisfying the above-mentioned specific properties in the intermediate layer is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, further preferably 50 to 100% by mass, and particularly preferably 70 to 100% by mass.

[0085] The intermediate layer may contain any component other than the substance satisfying the above-mentioned specific properties within a range not impairing the effects of the present application.

[0086] As optional components, colorants, fluorescent agents, ultraviolet absorbers, infrared absorbers, magnetic materials, stress relaxants, etc. can be cited. In addition, fillers and particles can also be compounded to the materials constituting the intermediate layer to impart functions such as coloring, fluorescence, ultraviolet absorption, infrared absorption, magnetism, and stress relaxation.

[0087] (Boards and glass panels)

[0088] It is preferred that the peak values ​​of the resonance frequencies of the plate on one side and the plate on the other side of the two plates are different, and it is more preferred that the ranges of the resonance frequencies do not overlap. However, even if the ranges of the resonance frequencies of the plate on one side and the plate on the other side overlap or the peak values ​​are the same, due to the presence of the intermediate layer, even if the plate on one side resonates, the vibration of the plate on the other side will not be synchronized, and thus the resonances cancel each other to some extent, so that a higher loss factor can be obtained compared to the case of a single glass plate.

[0089] That is, when the resonance frequency (peak) of the plate on one side is set to Qa, the half-width of the resonance amplitude is set to wa, and the resonance frequency (peak) of the plate on the other side is set to Qb, and the half-width of the resonance amplitude is set to wb, it is preferred to satisfy the following relationship [Formula 1].

[0090] (wa+wb) / 4<|Qa-Qb|···[Formula 1]

[0091] The larger the value of the left side in the above-mentioned [Formula 1] is, the larger the difference (|Qa−Qb|) in the resonance frequency of the plates on both sides becomes, and a high loss factor can be obtained, which is preferable.

[0092] Therefore, it is more preferable to satisfy the following [Formula 1′], and it is even more preferable to satisfy the following [Formula 1″].

[0093] (wa+wb) / 2<|Qa-Qb|···[Formula 1']

[0094] (wa+wb) / 1<|Qa-Qb|···[Formula 1”]

[0095] In addition, the resonance frequency (peak top) of the plate and the half-value width of the resonance amplitude can be measured by the same method as the loss factor in the glass plate structure.

[0096] The smaller the mass difference between the plate on one side and the plate on the other side, the better. It is more preferable that there is no mass difference. In the case of a mass difference between the plates, although the heavier plate can suppress the resonance of the lighter plate, the lighter plate is difficult to suppress the resonance of the heavier plate. That is, if the mass ratio is uneven, the resonances cannot be canceled out in principle due to the difference in inertial force.

[0097] The mass ratio of the two plates represented by (mass of the plate A on one side / mass of the plate B on the other side) is preferably 0.8 to 1.25, more preferably 0.9 to 1.11, and further preferably 1.0.

[0098] From the viewpoint of safety, the total thickness of the two plates is preferably 1.0 mm or more, more preferably greater than 1.0 mm, further preferably 1.5 mm or more, further preferably 2 mm or more, and particularly preferably 3 mm or more.

[0099] The glass plate structure having the total thickness of the two plates within the above range is suitable for use in opening parts for buildings and vehicles for suppressing generation of noise due to resonance phenomena.

[0100] The loss coefficient of at least one of the plates on one side and the other side is large, and the vibration attenuation of the structure is also large, which is preferably used as a vibration plate. Specifically, the loss coefficient of the plate at 25°C is preferably 1×10 －4 More preferably 3×10 －4 More preferably, 5×10 －4 The upper limit is not particularly limited, but is preferably 5×10 －3 In addition, it is more preferable that both the plate on one side and the plate on the other side have the above-mentioned loss coefficient.

[0101] In addition, the loss factor of the plate can be measured by the same method as the loss factor in the above-mentioned glass plate structure.

[0102] The longitudinal wave sound velocity value of at least one of the plates on one side and the other side in the plate thickness direction is high, and the reproducibility of sound in the high-frequency region is improved, so it is preferably used as a vibration plate. Specifically, the longitudinal wave sound velocity value of the plate is preferably 4.0×10 3 m / s or more, more preferably 4.5×10 3 m / s or more, more preferably 5.0×10 3 The upper limit is not particularly limited, but is preferably 7.0×10 3 m / s or less. In addition, it is more preferable that both the plate on one side and the plate on the other side satisfy the above-mentioned sound velocity value.

[0103] The sound velocity value of the plate can be measured by the same method as the sound velocity value of the longitudinal wave in the above-mentioned glass plate structure.

[0104] The surface of the pair of plates in contact with the intermediate layer may have a sliding layer. The sliding layer is a general term for a layer having sliding properties between the intermediate layer and the plate, for example, by waterproof, oil-repellent, hydrophobic or hydrophilic surface treatment, oil surface, fluorine coating, silicone coating, etc. The means for obtaining the sliding properties are not limited to the above means. By having a sliding layer, stable acoustic properties can be ensured and stable quality can be obtained.

[0105] In the glass plate structure according to the present invention, at least one of the plates on one side and the plates on the other side is composed of a glass plate. The glass plate here refers to inorganic glass and organic glass. As organic glass, generally, there are PMMA resins, PC resins, PS resins, PET resins, cellulose resins, etc., which are widely known as transparent resins.

[0106] The raw material of the other plate is arbitrary, and various raw materials can be used, such as resin plates formed of resins other than organic glass, metal plates such as aluminum, and ceramic plates formed of ceramics. From the viewpoints of design, processability, and weight, organic glass, resin materials, composite materials, fiber materials, and metal materials are preferably used, and from the viewpoint of vibration characteristics, inorganic glass, composite materials with high rigidity, fiber materials, metal materials, and ceramic materials are preferably used.

[0107] As the resin material, it is preferred to use a resin material that can be formed into a flat plate or a curved plate. As a composite material or a fiber material, it is preferred to use a resin material, a carbon fiber, a Kevlar fiber, etc. that is composited with a high-hardness filler. As a metal material, it is preferably aluminum, magnesium, copper, silver, gold, iron, titanium, SUS, etc., and other alloy materials, etc., can also be used as needed.

[0108] As the ceramic material, Al is more preferably used. 2 O 3 、SiC、Si 3 N 4 , AlN, mullite, zirconia, yttrium oxide, YAG and other ceramics and single crystal materials. In addition, for the ceramic material, a material having light transmittance is particularly preferred.

[0109] When inorganic glass is used in the glass plate constituting at least one sheet, the composition is not particularly limited, but is preferably in the following ranges in terms of mass % based on oxides, for example.

[0110] SiO 2 : 40-80 mass%, Al 2 O 3 : 0-35 mass %, B 2 O 3 : 0-15 mass%, MgO: 0-20 mass%, CaO: 0-20 mass%, SrO: 0-20 mass%, BaO: 0-20 mass%, Li2 O: 0-20 mass%, Na 2 O: 0-25 mass%, K 2 O: 0-20 mass%, TiO 2 : 0 to 10 mass %, and ZrO 2 : 0 to 10% by mass. The above composition accounts for 95% by mass or more of the entire glass.

[0111] The composition of the inorganic glass plate is more preferably in the following range.

[0112] SiO 2 : 55-75 mass%, Al 2 O 3 : 0-25 mass %, B 2 O 3 : 0-12 mass%, MgO: 0-20 mass%, CaO: 0-20 mass%, SrO: 0-20 mass%, BaO: 0-20 mass%, Li 2 O: 0-20 mass%, Na 2 O: 0-25 mass%, K 2 O: 0-15 mass%, TiO 2 : 0 to 5 mass %, and ZrO 2 : 0 to 5% by mass. The above composition accounts for 95% by mass or more of the entire glass.

[0113] From the viewpoint of vibration characteristics, in the glass plates constituting at least one plate, the smaller the specific gravity of the glass plates, the less energy is required to vibrate the glass plates. From the viewpoint of vibration characteristics alone, it is better to use inorganic glass than organic glass. Specifically, the specific gravity of the glass plate is preferably 2.8 or less, more preferably 2.6 or less, and further preferably 2.5 or less. The larger the value of the Young's modulus of the glass plate divided by the density, that is, the larger the specific elastic modulus, the higher the rigidity can be. Specifically, the specific elastic modulus is 2.5×10 7 m 2 / s 2 More preferably, 2.8×10 7 m 2 / s 2 More preferably, 3.0×10 7 m 2 / s 2 The upper limit is not particularly limited, but is preferably 4.0×10 7 m 2 / s 2 the following.

[0114] In order to improve the transmittance of the glass plate structure, it is useful to integrate the refractive index. That is, the closer the refractive index of the glass plate constituting the glass plate structure is to that of the intermediate layer, the more reflection and interference on the interface can be prevented, which is preferred. Among them, the difference between the refractive index of the intermediate layer and the refractive index of the pair of glass plates in contact with the intermediate layer is 0.3 or less, more preferably 0.2 or less, further preferably 0.1 or less, particularly preferably 0.05 or less, and even more preferably 0.01 or less.

[0115] At least one or two of the plates constituting the glass plate structure can be functionalized. This is useful when the glass plate structure is to be designed or when the glass plate structure is to have functions such as IR cutoff, UV cutoff, privacy glass, etc. For example, operations such as evaporating a metal film on the glass surface and further printing a conductive resin and paint to form a wiring pattern can be performed.

[0116] The plates constituting the glass plate structure may be at least one glass plate, but two or more glass plates may be used. In this case, glass plates of completely different compositions may be used, glass plates of completely the same composition may be used, or a combination of glass plates of the same composition and glass plates of different compositions may be used. Among them, it is more preferable to use two or more glass plates of different compositions from the viewpoint of design and acoustic properties.

[0117] The same is true for the quality and thickness of the glass plates; they may be completely different, completely the same, or partially different.

[0118] As at least one of the glass plates constituting the glass plate structure, a physically strengthened glass plate or a chemically strengthened glass plate may be used. This is useful for preventing the glass plate structure from being damaged. When the strength of the glass plate structure is to be increased, it is preferred that the glass plate located on the outermost surface of the glass plate structure be a physically strengthened glass plate or a chemically strengthened glass plate, and it is more preferred that all the glass plates of the structure be physically strengthened glass plates or strengthened glass plates.

[0119] In addition, as the glass plate, from the point of improving the longitudinal wave sound velocity value and strength, it is useful to use crystallized glass or phase-separated glass. In particular, when it is desired to improve the strength of the glass plate structure, it is preferred that the glass plate located on the outermost surface of the glass plate structure is crystallized glass or phase-separated glass.

[0120] As long as the effects of the present invention are not impaired, a coating layer may be prepared or a film may be laminated on the outermost surface of at least one side of the glass plate structure. As for the coating and the film, conventionally known coatings and films may be used, and examples of the coating include waterproof coatings, hydrophilic coatings, water-slip coatings, oil-proof coatings, light-proof reflection coatings, heat-insulating coatings, and high-reflection coatings. In addition, examples of the film include anti-glass scattering films, color films, UV cut-off films, IR cut-off films, heat-insulating films, and electromagnetic wave shielding films.

[0121] The shape of the glass plate structure can be appropriately designed according to the application, and can be a flat plate or a curved surface. In order to improve the output sound pressure level in the low frequency band, the glass plate structure can be made into a structure with a shell or a baffle. The material of the shell or the baffle is not particularly limited, and the structure of the present invention is preferably used. In addition, a through hole can be opened for physical fixation using metal points, tin points, etc., and a hole can be opened on at least one sheet for mounting a vibrator.

[0122] A frame may be provided on the outermost surface of at least one side of the glass plate structure within the range that does not impair the effect of the present invention. The frame is useful when the rigidity of the glass plate structure is to be increased, when low-frequency vibration is to be suppressed, or when a curved surface shape is to be maintained. As the material of the frame, a conventionally known material may be used, for example, a metal material such as aluminum, iron, stainless steel, magnesium, Al 2 O 3 、SiC、Si 3 N 4 , AlN, mullite, zirconia, yttrium oxide, YAG and other ceramics and single crystal materials, carbon fiber, Kevlar fiber and other fiber materials, other composite materials, PMMA, PC, PS, PET, cellulose and other organic glass materials, transparent resin materials, butyl rubber, silicone rubber, polyurethane rubber and other rubber materials, polyurethane gel, silicone gel and other vibration-proof gel materials, eucalyptus, teak, plywood and other wood, etc.

[0123] In order to prevent the intermediate layer from leaking from the frame, a sealing material may be provided between the glass sheet structure and the frame.

[0124] At least a portion of the outer peripheral end surface of the glass plate structure may be sealed with a member that does not hinder the vibration of the glass plate structure. As the sealing material, a sealing tape, resin, highly elastic rubber, gel, etc. may be used.

[0125] As the sealing material, acrylic, cyanoacrylate, epoxy, silicone, polyurethane, phenolic resin, etc. can be used.

[0126] As the curing method, two liquid mixed type, moisture curing, heat curing, ultraviolet curing, visible light curing, etc. can be enumerated. In addition, thermoplastic resin (hot melt bonding) can also be used. As examples, ethylene vinyl acetate system, polyolefin system, polyamide system, synthetic rubber system, acrylic acid system, polyurethane system can be enumerated.

[0127] As the rubber, for example, natural rubber, synthetic natural rubber, butadiene rubber, styrene-butadiene rubber, butyl rubber, nitrile rubber, ethylene-propylene rubber, chloroprene rubber, acrylic rubber, chlorosulfonated polyethylene rubber (Hypalon), polyurethane rubber, silicone rubber, fluororubber, ethylene-vinyl acetate rubber, epichlorohydrin rubber, polysulfide rubber (Thiokol) and hydrogenated nitrile rubber can be used.

[0128] (Method for producing glass plate structure)

[0129] The glass plate structure according to the present invention can be obtained by forming an intermediate layer between a pair of plates.

[0130] There is no particular limitation on the method of forming an intermediate layer between a pair of plates. In the case of a structure composed of plates and intermediate layers, examples thereof include: a method of forming an intermediate layer on the surface of a plate on one side and placing a plate on the other side thereon; a method of bonding plates with intermediate layers formed on their surfaces respectively; a method of injecting an intermediate layer into the gap between two plates, etc.

[0131] (Embodiment of glass plate structure)

[0132] Figure 1 A cross-sectional view showing a glass sheet structure 10 according to a first embodiment of the present invention.

[0133] The glass plate structure 10 includes a first plate 11 and a second plate 12 , and an intermediate layer 16 provided between the first plate and the second plate, and at least one of the first plate and the second plate is formed of a glass plate.

[0134] Figure 2 It is a cross-sectional view showing another embodiment of the glass plate structure 10 . Figure 2 The glass plate structure 10 includes Figure 1 In addition to the structure of the glass plate structure 10, it also includes other plates 13. According to such a structure, the strength of the glass plate structure 10 can be increased.

[0135] Figure 3 It is a cross-sectional view showing another embodiment of the glass plate structure 10 . Figure 3 The glass plate structure 10 includes Figure 1In addition to the structure of the glass plate structure 10, the end surface of the glass plate structure further has an external sealing material 31. This can prevent physical damage to the intermediate layer 16. At this time, if the light refractive index of the intermediate layer matches that of the external sealing material, the interface between the intermediate layer and the external sealing material is not easily recognized, and if the light refractive index of the first plate 11 and the second plate 12 matches that of the intermediate layer 16, the interface between the first plate 11 and the second plate 12 and the intermediate layer 16 is not easily recognized.

[0136] Figure 4 FIG. 2 is a diagram showing another embodiment of the glass plate structure 10. Figure 4 (a) is a plane diagram, Figure 4 (b) is a cross-sectional view. Figure 4 In the glass plate structure 10 of FIG. 1 , a frame 30 is provided at the outer edge of the glass plate structure 10, at least on the outermost surface of the glass plate structure 10. This is a cross-sectional view showing another embodiment of the glass plate structure 10. A sealing material 31 is provided between the glass plate structure 10 and the frame 30.

[0137] Figure 5 FIG. 2 is a diagram showing another embodiment of the glass plate structure 10. Figure 5 (a) is a plane diagram, Figure 5 (b) is a cross-sectional view. Figure 5 As shown, the frame 30 may be provided on the outermost surface of the first plate 11 of the glass plate structure 10 .

[0138] Figure 6 FIG. 2 is a diagram showing another embodiment of the glass plate structure 10. Figure 6 (a) is a plan view of the glass plate structure, Figure 6 (b) is along Figure 6 The cross-sectional view of line II in (a) is as follows: Figure 6 (c) is Figure 6 An enlarged view of part C in (b).

[0139] like Figure 6 (b) Figure 6 As shown in (c), the end faces of the first plate 11 and the second plate 12 are staggered to form a stepped portion 50 in a cross-sectional view. Then, in the stepped portion 50, the sealing material 31 is provided in a manner to seal at least the intermediate layer 16.

[0140] The sealing material 31 is in close contact with the end face 11a of the first plate 11, the end face 16a of the intermediate layer 16, and the main face 12a of the second plate 12 in the step portion 50. With such a structure, the intermediate layer 16 is sealed by the sealing material 31, and while preventing leakage of the intermediate layer 16, the bonding between the first plate 11, the intermediate layer 16, and the second plate 12 is strengthened, thereby increasing the strength of the glass plate structure 10.

[0141] In addition, in the present embodiment, in the step portion 50, the end face 11a of the first plate 11 and the end face 16a of the intermediate layer 16 are configured to be perpendicular to the main surface 12a of the second plate 12. As a result, the sealing material 31 has an L-shaped profile extending along the step portion 50 in the cross-sectional view. With such a configuration, the bonding between the first plate 11, the intermediate layer 16, and the second plate 12 is further strengthened, and the strength of the glass plate structure 10 is further increased.

[0142] Furthermore, in this embodiment, the sealing material 31 has a tapered surface 31a. The edge of the glass plate structure 10 can be tapered, and by adopting such a shape of the sealing material 31, the same effect as that of processing the glass plate structure can be obtained.

[0143] Figure 7 FIG. 2 is a diagram showing another embodiment of the glass plate structure 10. Figure 7 (a) is a plan view of the glass plate structure, Figure 7 (b) is along Figure 7 sectional view along the line I-I in (a). In this embodiment, unlike another embodiment, the step portion 50 and the sealing material 31 are not arranged at the periphery of the glass plate structure 10, but are arranged approximately in the center of the glass plate structure 10 in a plan view. Such a structure also satisfies the requirement that the end faces of the two plates (the first plate 11 and the second plate 12) are staggered. Moreover, the strength of the glass plate structure 10 is increased. In addition, a sealing tape 40 is affixed to the end face of the periphery of the glass plate structure 10 to seal the intermediate layer 16.

[0144] <Vibration plate, opening parts>

[0145] The present invention relates to a vibration plate including the glass plate structure and a vibrator, and an opening member using the glass plate structure.

[0146] As a vibration plate, for example, by setting one or more vibration elements or vibration detection elements (vibrators) on one or both sides of a glass plate structure, it can function as a frame vibrator or frame speaker of a speaker, microphone, earphone, mobile device, etc. In order to increase the output sound pressure level, it is desirable to set two or more vibration elements on both sides of the glass plate structure. Generally speaking, it is desirable that the position of the vibrator relative to the vibration plate is in the central part of the structure, but the vibrator can also be set at the end of the glass plate structure. In addition, the glass plate structure has a high degree of freedom in size, shape, color tone, etc., and design can be applied, so a vibration plate with excellent design can be obtained. In addition, by sampling the sound or vibration with a sound collection microphone or vibration detector arranged on the surface or near the glass plate structure, the glass plate structure produces a vibration in the same phase or opposite phase with it, thereby amplifying or canceling the sampled sound or vibration. At this time, when the characteristics of the sound or vibration at the above-mentioned sampling point change based on a certain acoustic transfer function between propagation to the glass plate structure vibration plate, and when the glass plate structure has an acoustic conversion transfer function, the amplitude and phase of the control signal are corrected by using a control filter, so that the vibration can be amplified or eliminated with good accuracy. When constructing the above-mentioned control filter, for example, the least squares method (LMS) algorithm can be used.

[0147] As a more specific structure, for example, the following structure can be used: all or at least one glass plate of the multi-layered glass is set as the glass plate structure of the present invention, the vibration level of the plate on the inflow side of the sound wave vibration of the control object, or the sound pressure level of the space between the glasses is sampled, and after appropriately performing signal correction with a control filter, it is output to the vibration element arranged on the glass plate structure on the outflow side of the sound wave vibration.

[0148] The glass plate structure of the present invention can be used as a vibration component for interior decoration of transportation machinery such as vehicles, and as a vehicle-mounted or aircraft-mounted speaker. For example, as an interior decoration component that functions as a speaker, the dashboard, the front panel, the ceiling, the door, the sun visor, the car navigation system, the electro-optical display such as the car display, and the lighting machine can be turned into a speaker. It is also possible to turn the existing windshield, rear glass, side glass, side mirror, rearview mirror, inner window and outer window of the double-layer window, the partition between the driver's seat and the back seat, and the partition between the rear seats, etc., which are installed in the car, into a speaker. It can also be installed on trams, airplanes, helicopters, etc. for the same purpose. Furthermore, these can also function as microphones and vibration plates for active noise reduction.

[0149] In addition, the above-mentioned uses are not limited to vehicle, aircraft and electronic equipment uses, and can also be used as building materials. By using this vibration plate, window glass, door glass, display cabinets, etc. that require a thick plate thickness for safety can also be turned into speakers.

[0150] Examples of the opening member include opening members used in construction and transportation machinery. For example, when a glass plate structure that is not likely to resonate in the frequency band of noise generated by the drive unit of a vehicle, aircraft, ship, generator, etc. is used, a particularly excellent effect of suppressing the noise can be obtained. In addition, the glass plate structure can also be given functions such as IR cutoff, UV cutoff, and coloring.

[0151] When applied to an opening part, a vibration plate having one or more vibration elements or vibration detection elements (vibrators) arranged on one or both sides of a glass plate structure can function as a speaker or microphone. By using the glass plate structure of the present invention, it is easy to reproduce the sound in the low-frequency area and the high-frequency area which have been difficult to reproduce so far. In addition, the size, shape, color tone, etc. of the glass plate structure have a high degree of freedom, and design can be applied, so an opening part with excellent design can be obtained. In addition, by sampling the sound or vibration with a sound collection microphone or a vibration detector arranged on the surface or near the glass plate structure, the glass plate structure generates a vibration in the same phase or opposite phase with the glass plate structure, thereby amplifying or canceling the sampled sound or vibration.

[0152] More specifically, when used as an in-car speaker, an out-car speaker, a windshield, a rear glass, a side glass, or a ceiling glass for a vehicle with a sound insulation function, a mechanism that can only pass or block specific sound wave vibrations can be provided. In addition, it can also be used as a vehicle window, a structural component, or a decorative plate that improves waterproofness, snow adhesion resistance, ice adhesion resistance, and antifouling properties through sound wave vibrations. Specifically, in addition to automotive window glass and mirrors, it can also be used as a lens, a sensor, and their protective glass.

[0153] As opening parts for buildings, they can be used as window glass, door glass, ceiling glass, dimming glass, interior materials, exterior materials, decorative materials, structural materials, outer walls, sound insulation boards and sound insulation walls, and protective glass for solar cells that function in the form of vibration plates and vibration detection devices. They can also be used as acoustic reflection (reverberation) plates. In addition, waterproofness, anti-snow adhesion, anti-ice adhesion, and anti-fouling properties can also be improved by sound wave vibration. In addition, they can also be used as crack detection, pest expelling, animal damage countermeasures, ultrasonic communication, echo diagnosis, etc.

[0154] Example

[0155] Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited thereto.

[0156] <Glass plate structure>

[0157] Glass plates A and B of 10 mm×60 mm×1.1 mm were prepared, and an intermediate layer material was sandwiched therebetween so as to achieve a predetermined film thickness. In this manner, glass plate structures of Examples 1 to 6 were obtained.

[0158] The compositions (mass %) and physical property values ​​of the glass plate A and the glass plate B are as follows.

[0159] (Glass Plate A)SiO 2 :61.5%、Al 2 O 3 :20%、B 2 O 3 : 1.5%, MgO: 5.5%, CaO: 4.5%, SrO: 7%, density: 2.7g / cm 3 、Young's modulus: 85GPa、Specific elastic modulus: 3.2×10 7 m 2 / s 2 , Surface roughness: (JIS B0601) arithmetic mean height Ra ≤ 1.0μm.

[0160] (Glass Plate B)SiO 2 :60%、Al 2 O 3 :17%、B 2 O 3 : 8%, MgO: 3%, CaO: 4%, SrO: 8%, density: 2.5g / cm 3 , Young's modulus: 77GPa, specific elastic modulus: 3.1×10 7 m 2 / s 2 , Surface roughness: (JIS B0601) arithmetic mean height Ra ≤ 1.0μm.

[0161] The physical properties of the materials used for the intermediate layer are shown in the table below. The compression storage modulus, compression loss modulus and loss factor tanδ (=compression storage modulus / compression loss modulus) at 25°C and 1 Hz were measured using MCR301 (manufactured by Anton Paar). The results are shown in the table below.

[0162]

Table 1

[0163] Table 1

[0164] project Compression storage elastic modulus [Pa] Compression loss elastic modulus [Pa] tanδ Silicone gel <![CDATA[1.2×10 3 ]]> <![CDATA[4.9×10 2 ]]> 0.41 Adhesives <![CDATA[2.7×10 5 ]]> <![CDATA[1.1×10 5 ]]> 0.39

[0165] <Loss coefficient measurement>

[0166] Using an exciter, a frequency signal of 20 Hz to 6000 Hz was applied to each glass sheet structure, and the signal was scanned at Δ1 Hz to measure the amplitude of the end of the glass sheet structure at each frequency. 0 The frequency at which the peak value is reduced by 3dB is set to ω 1 and ω 2 , with loss coefficient = (ω 2 -ω 1 ) / ω 0 The loss factor of the glass plate structure is obtained.

[0167] The results are shown in the following table.

[0168] <Determination of longitudinal wave sound velocity value>

[0169] The longitudinal wave velocity value can be measured according to the ultrasonic pulse method described in Japanese Industrial Standards (JIS-R1602-1995). It is the value of the following table.

[0170] It should be noted that Examples 1 and 2 are examples, and Examples 3 to 6 are comparative examples.

[0171]

Table 2

[0172]

[0173] The adhesive dampens vibrations by a dynamic viscoelastic mechanism, so the thicker the intermediate layer using the adhesive is, the higher the loss factor is. On the other hand, as the thickness of the board increases, the intermediate layer has to be thicker.

[0174] On the other hand, in the glass sheet structure of the present invention, by using a material having a compression storage elastic modulus of a specific value or less in the intermediate layer, it is found that the loss factor increases as the thickness of the intermediate layer is thinner.

[0175] In addition, the smaller the thickness of the intermediate layer is, the higher the sound velocity value of the glass sheet structure is.

[0176] Therefore, a glass sheet structure using a material having a compression storage modulus of a specific value or less for the intermediate layer has both high values ​​of the loss factor and the sound velocity value.

[0177] The above results show that the glass plate structure of the present invention can obtain high loss coefficient and sound velocity values ​​and has high acoustic performance.

[0178] Although the present invention has been described with reference to details or specific embodiments, it is clear to those skilled in the art that various changes and modifications can be implemented without departing from the spirit and scope of the present invention. This application is based on Japanese patent application (Japanese Patent Application No. 2020-142842) filed on August 26, 2020, the contents of which are incorporated herein by reference.

[0179] Explanation of symbols

[0180] 10…Glass plate structure

[0181] 11… Plate 1

[0182] 11a…End surface of the first plate

[0183] 12… Plate 2

[0184] 12a…Main surface of the second plate

[0185] 13…Other boards

[0186] 16…Middle Layer

[0187] 30…Frame

[0188] 31… Sealing material

[0189] 31a…conical surface

[0190] 40…Sealing tape

[0191] 50…step difference

Claims

1. A glass plate structure comprising two or more plates, wherein at least one pair of the plates comprises an intermediate layer between the plates, At least one of the pair of plates is a glass plate, The intermediate layer is composed of silicone gel and satisfies all of the following properties (1) to (3). The loss coefficient of the glass plate structure at 25° C. is 0.01 or more, and the longitudinal wave sound velocity value in the plate thickness direction is 4.0×10 3 m / s or more; (1) The thickness of the intermediate layer is 20 μm or less, (2) The compression storage elastic modulus at 25°C is 1.0×10 4 Below Pa, (3) At 25°C and 1 Hz, the compression storage modulus is higher than the compression loss modulus.

2. The glass sheet structure according to claim 1, in, The pair of plates are all glass plates, The loss coefficient of the glass plate structure at 25°C is 0.01 or more, and the longitudinal wave sound velocity value in the plate thickness direction is 5.0×10 3 m / s or more.

3. The glass sheet structure according to claim 1 or 2, in, The total thickness of the pair of plates is 1.0 mm or more, The intermediate layer and the plate satisfy the following formula A, 4. The glass sheet structure according to claim 1 or 2, in, The average Young's modulus of the pair of plates at 25° C. is 20 GPa or more.

5. The glass sheet structure according to claim 1 or 2, in, The product of the total thickness of the pair of plates and the average Young's modulus of the pair of plates is 2.0×10 7 Pa·m and above.

6. The glass sheet structure according to claim 1 or 2, in, A value obtained by dividing the thickness of the intermediate layer by the total thickness of the pair of plates is 0.02 or less.

7. The glass sheet structure according to claim 1 or 2, in, The value obtained by dividing the compressive storage elastic modulus of the intermediate layer material by the average Young's modulus of the pair of plates is 1×10 4 the following.

8. The glass sheet structure according to claim 1 or 2, in, The value obtained by dividing the mass of the plate A on one side of the pair of plates by the mass of the plate B on the other side of the pair of plates is 0.8 to 1.

25.

9. The glass sheet structure according to claim 1 or 2, in, The loss factor of at least one of the pair of plates at 25°C is 1×10 －4 above.

10. The glass sheet structure according to claim 1 or 2, in, The longitudinal wave sound velocity value of at least one of the pair of plates in the plate thickness direction is 4.0×10 3 m / s or more.

11. The glass sheet structure according to claim 1 or 2, in, The pair of plates has a sliding layer on surfaces in contact with the intermediate layer.

12. The glass sheet structure according to claim 1 or 2, in, The specific gravity of the glass plate is 2.8 or less.

13. The glass sheet structure according to claim 1 or 2, in, The specific elastic modulus of the glass plate is 2.5×10 7 m 2 / s 2 above.

14. The glass sheet structure according to claim 1 or 2, in, The difference between the refractive index of the intermediate layer and the refractive index of the pair of plates in contact with the intermediate layer is 0.3 or less.

15. The glass sheet structure according to claim 1 or 2, in, The glass plate structure has a curved shape. 16 . A vibration plate comprising: the glass plate structure according to claim 1 , and at least one vibrator provided on one or both surfaces of the glass plate structure. 17 . An opening member using the glass plate structure according to claim 1 or the vibration plate according to claim 16 .

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