soundproofing structure

Abstract

The present invention addresses the problem of providing a sound-insulating structure that can obtain a high sound-insulating effect even when a concave-convex structure having a concave-convex structure is installed on a member with high rigidity. A concave-convex sheet member having a concave-convex structure provided with a sheet portion and a plurality of convex portions provided on the surface of the sheet portion; a flexible member provided on the concave-convex sheet member, the flexible member is provided on at least one surface of the concave-convex sheet member, either on a surface on which convex portions are provided or on a surface opposite to the surface on which convex portions are provided, and in a compression test using a compression tester, a load giving a deformation rate of 4% is 160 kPa or less; The concave-convex sheet member is a sound-insulating sheet in which the weight ratio of the convex portions to the sheet portion, expressed as (weight of the convex portions / weight of the sheet portion), is 0.7 or more.

Description

[Technical Field]

[0001] The present invention relates to a sound-insulating structure having a concave-convex sheet member, a soft member, and an adherend on which the soft member is placed. [Background technology]

[0002] Buildings such as apartment buildings, office buildings, and hotels require quietness suitable for indoor use by blocking outdoor noise from automobiles, trains, airplanes, ships, and the like, as well as equipment noise and human voices generated inside the building. Furthermore, in vehicles such as automobiles, trains, airplanes, and ships, it is necessary to reduce indoor noise by blocking wind noise and engine noise to provide a quiet and comfortable space for passengers. Therefore, research and development has been conducted on means for blocking the transmission of noise and vibration from the outdoors to the interior, or from the exterior of a vehicle to the interior, i.e., sound-insulating means. In recent years, sound-insulating materials that can be adapted to complex shapes have been required in order to increase the height of buildings, improve the energy efficiency of vehicles, and increase the design flexibility of buildings, vehicles, and their facilities.

[0003] Conventionally, improvements have been made to the structure of sound-insulating materials, particularly sheet-like materials, in order to improve their sound-insulating performance. For example, known methods include a method of combining multiple rigid flat plate materials such as gypsum board, concrete, steel plate, glass plate, or resin plate (Patent Document 1), a method of forming a hollow double-wall structure or hollow triple-wall structure using gypsum board or the like (Patent Document 2), a method of combining a flat plate material with multiple independent stump-shaped protrusions (Patent Document 3), and a method of combining a flat plate material with multiple independent stump-shaped protrusions and sound-absorbing material (Patent Document 4). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-231316 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-227109 [Patent Document 3] International Publication No. 2017 / 135409 [Patent Document 4] Japanese Patent Application Laid-Open No. 2000-265593 Summary of the Invention [Problem to be solved by the invention]

[0005] Among the conventional sound-proofing materials, those described in Patent Documents 3 and 4 comprise a rubber-elastic sheet and cylindrical protrusions arranged in multiple rows and columns on the surface of the sheet. They function by causing the protrusions to resonate in response to incoming sound, and are known to provide sound-proofing and vibration-damping performance that exceeds the mass law. In recent years, there has been a demand for precision instruments, home appliances, and the like to be equipped with a function to block low-frequency sounds and vibrations emitted by the instruments while they are in use. In order to meet this demand, even for sound-proofing members that have the elastic sheet and cylindrical protrusions, investigations are being conducted into the shielding performance by adjusting the material and size of the protrusions.

[0006] However, in order to improve the soundproofing effect in the low frequency band, it is necessary to make the columnar protrusions larger or to introduce weights into the protrusions to make them heavier, which inevitably makes the soundproofing material thicker, increasing its size and weight, and making it impossible to meet the demand for installing it in small, lightweight equipment to block low frequency band sounds.

[0007] Various studies have been carried out to address this issue, and a linear structure has been developed on a substrate that is more rigid than conventional sound-insulating materials. A compact, textured sheet has been developed that can achieve high sound insulation in the low frequency band by arranging multiple convex portions in a row in the same direction, without increasing the height of the portions protruding above the substrate. It is believed that this arrangement allows the convex portions to function as local (preferably local and periodic) rigidity and mass when sound is incident, exciting a vibration mode in the substrate corresponding to the distance between the convex portions, causing the substrate portion to vibrate in response to the incident sound, thereby increasing the sound insulation strength of the textured sheet. Furthermore, by designing the shape of the convex portions on the substrate and the thickness of the substrate, it is possible to freely adjust the sound insulation frequency band.

[0008] However, when such a textured sheet that utilizes the vibration of the substrate portion is used as a sound-insulating member, if the substrate portion is placed directly on a member such as a hard metal part with high rigidity, or if sound waves with sufficient sound pressure are not incident on the textured sheet, the substrate portion cannot vibrate, resulting in a decrease in sound-insulating performance, and therefore there are limitations to how it can be used. That is, with the member described in Patent Document 4, if the rigidity of the sound-absorbing material is high or the sound-absorbing material is thick and sound waves with sufficient sound pressure are not incident on the textured film, the sound-insulating effect derived from the textured film is lost.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a sound-insulating structure that can obtain a high sound-insulating effect even when a concave-convex structure having a concave-convex structure is installed on a highly rigid member. [Means for solving the problem]

[0010] In order to solve the above-mentioned problems, the present inventors have thoroughly investigated the configuration of a sound-insulating structure using a concave-convex sheet member having a vibration mode effective for sound insulation in the base material portion, and have found that by using a concave-convex sheet member that combines a soft, easily deformable member as a concave-convex structure having a concave-convex structure and considering the position of the concave-convex sheet member relative to the sound source, a sound-insulating effect derived from the vibration of the sheet portion of the concave-convex sheet member can be achieved even on a member with a high specific gravity or rigidity, such as metal. In other words, the present inventors have found that when the concave-convex sheet member, the soft member, and the adherend on which the soft member is placed are layered in this order relative to the direction in which sound is incident, high sound-insulating properties are achieved in the sound-insulating frequency band of the concave-convex sheet member, thereby solving the above-mentioned problems.

[0011] That is, the gist of the present invention is as follows. [1] A soft member in which the load giving a deformation rate of 4% in a compression test using a compression testing machine is 160 kPa or less; an adherend on which the flexible member is to be placed; The sound-insulating structure includes a concave-convex sheet member having a concave-convex structure, The sound-insulating structure is provided so that the soft member is disposed between the adherend and the concave-convex sheet member. [2] The uneven structure has a sheet portion and a convex portion provided on a surface of the sheet portion, The sound-insulating structure according to [1], wherein a weight ratio of the convex portions to the sheet portion expressed as (weight of the convex portions / weight of the sheet portion) is 0.7 or more. [3] The sound-insulating structure according to [2], which has an adhesive layer between the uneven sheet member and the flexible member. [4] The surface density of the sheet portion is 2.5 kg / m 2 A sound-insulating structure according to either [2] or [3] below. [5] The density of the convex portion is 100 kg / m 3 The sound-insulating structure according to any one of [2] to [4] above. [6] The sound-insulating structure according to any one of [2] to [5], wherein the height of the convex portion is 0.1 mm or more. [7] The number ratio of the convex portions is 1000 to 10000 / m2 [2]~[6] The sound-insulating structure according to any one of the preceding claims. [8] A sound insulation structure according to any one of [2] to [7], wherein a load giving a deformation rate of 4% in a compression test using the compression tester is 0.15 kPa or more. [9] The weight ratio of the convex portions to the sheet portion of the concave-convex sheet member, expressed as (weight of the convex portions / weight of the sheet portion), is 5 or less, and The sound-insulating structure according to any one of [2] to [8], wherein the soft member is such that a load giving a deformation rate of 4% in a compression test using a compression tester is 10 kPa or less.

[10] The sound-insulating structure according to any one of [2] to [9], wherein the uneven sheet member has the uneven structure provided on the side where the flexible member is present or on the opposite side.

[11] The sound-insulating structure according to any one of [2] to

[10] , which is used together with a sound source and is placed with the concave-convex sheet member side facing the sound source.

[12] The sound-insulating structure according to any one of [2] to

[11] , which simultaneously satisfies the conditions represented by the following formulas (A) to (C): (TL1-TL2)-(TL3-TL4)>3dB ···(A) TL1-TL2>0dB (B) TL3-TL4>0dB (C) TL1 (dB): Sound transmission loss of a sound insulation structure when the textured sheet member is installed facing the sound source. TL2 (dB): Sound transmission loss of a sound insulation structure when the textured sheet is replaced with a flat sheet with the same mass and area under the conditions of TL1. TL3 (dB): Sound transmittance of a sound insulation structure when the adherend is placed facing the sound source TL4 (dB): Sound transmission loss of a sound insulation structure when the textured sheet is replaced with a flat sheet with the same mass and area as the textured sheet under the condition of TL3. TL1 and TL2 are the sound transmission losses at the frequency when TL1-TL2 is at its maximum, and TL3 and TL4 are the sound transmission losses at the frequency when TL3-TL4 is at its maximum.

[13] A sound-insulating structure according to any one of [2] to

[12] , wherein the uneven sheet member comprises a sheet portion and a convex portion protruding linearly from the sheet portion, and uneven unit shapes each having the convex portion and a concave portion along the convex portion are repeatedly arranged in one or two directions on the sheet portion.

[14] The sound-insulating structure according to any one of [2] to

[13] , wherein the soft member is a nonwoven fabric.

[15] The sound-insulating structure according to any one of [2] to

[13] , wherein the soft member is a foam.

[16] A concave-convex sheet member having a concave-convex structure including a sheet portion and a plurality of convex portions provided on the surface of the sheet portion; a flexible member provided on the uneven sheet member, The soft member has a load of 160 kPa or less that gives a deformation rate of 4% in a compression test using a compression tester, The concave-convex sheet member is a sound-insulating sheet in which the weight ratio of the convex portions to the sheet portion, expressed as (weight of the convex portions / weight of the sheet portion), is 0.7 or more. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a sound-insulating structure that can obtain a high sound-insulating effect even when a concave-convex structure having a concave-convex structure is installed on a member with high rigidity. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic perspective view of an embodiment of a concave-convex sheet member according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view of the concave-convex sheet member of FIG. 1. [Figure 3] 1 is a schematic perspective view of an embodiment of a concave-convex sheet member according to an embodiment of the present invention. [Figure 4] 1 is a schematic perspective view of an embodiment of a concave-convex sheet member according to an embodiment of the present invention. [Figure 5] 1 is a schematic perspective view of an embodiment of a concave-convex sheet member according to an embodiment of the present invention. [Figure 6]1 is a schematic perspective view of an embodiment of a concave-convex sheet member according to an embodiment of the present invention. [Figure 7] 1 is a schematic perspective view of an embodiment of a concave-convex sheet member according to an embodiment of the present invention. [Figure 8] 1 is a schematic perspective view of an embodiment of a concave-convex sheet member according to an embodiment of the present invention. [Figure 9] 1 is a schematic cross-sectional view of an embodiment of a sound-insulating structure according to an embodiment of the present invention. [Figure 10] 1 is a schematic cross-sectional view of an embodiment of a sound-insulating structure according to an embodiment of the present invention. [Figure 11] FIG. 2 is a diagram showing a schematic cross-sectional end surface of an example of a mold used to manufacture a concave-convex sheet member. [Figure 12] 14 is a diagram illustrating a process for manufacturing a concave-convex sheet member using the mold of FIG. 13. FIG. [Figure 13] FIG. 1(A) is a schematic external view of a cylindrical mold, and FIG. 1(B) is a diagram illustrating the process of manufacturing a concave-convex sheet member using this mold. [Figure 14] 1 is a schematic cross-sectional view of an embodiment of a sound-insulating structure according to an embodiment of the present invention. [Figure 15] 10 is a graph showing the relationship between the peak value of the transmission loss difference with respect to the mass law and the weight ratio of the convex portion weight / sheet portion weight in shape models 1 to 41. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will be described in detail below. The following description is an example (typical example) of the present invention, and the present invention is not limited thereto. Furthermore, the present invention can be implemented with any modifications within the scope of the gist thereof. In this specification, the notation "~" indicates a range including the numbers before and after it. As used herein, "plurality" means two or more.

[0015] <Sound insulation structure> The sound-insulating structure according to an embodiment of the present invention (also simply referred to as the "sound-insulating structure") comprises: A soft member in which the load giving a deformation rate of 4% in a compression test using a compression testing machine is 160 kPa or less; an adherend on which the flexible member is to be placed; The sound-insulating structure includes a concave-convex sheet member having a concave-convex structure, The sound-insulating structure is provided such that the soft member is disposed between the adherend and the concave-convex sheet member.

[0016] The above-mentioned sound-insulating structure has a simple structure yet can ensure a high sound-insulating effect, which prevents the structure from becoming too large. Furthermore, since the sheet portion placed on the soft member is subject to little vibration inhibition from the member it comes into contact with, a high sound-insulating effect can be obtained even against sound waves with relatively low sound pressure. Furthermore, when the above-described sound-insulating structure is used together with a sound source, a configuration in which the concave-convex sheet member side faces the sound source can provide a higher sound-insulating effect than a configuration in which the adherend side faces the sound source. This is thought to be because sound waves with a higher sound pressure are incident on the concave-convex sheet member, causing the sheet portion to vibrate efficiently. Furthermore, by adjusting the shape of the protrusions, the distance between the protrusions, the thickness of the sheet, etc., it is possible to adjust the frequency of sound insulation. In this specification, the term "soft member" refers to a member that, as will be described later, applies a load of 160 kPa or less to a deformation rate of 4% in a compression test. In addition, in this specification, mass and weight are synonymous, and mass may be read as weight. Hereinafter, each embodiment of the present invention will be described with reference to the drawings. Note that each of the following embodiments is an example for explaining the present invention, and the present invention is not limited to only the embodiment.

[0017] [Concave and convex sheet material] (Configuration of the uneven sheet member) 1 and 2 are a schematic perspective view and a schematic cross-sectional view of a concave-convex sheet member 1, respectively, and Fig. 9 is a schematic cross-sectional view of the sound-insulating structure of this embodiment. The concave-convex sheet member 1 shown in the figure has a concave-convex structure 3, specifically, a concave-convex structure having a sheet portion 2 and protrusions 5 provided on the surface of the sheet portion. The concave-convex structure 3 may be provided on the side where the flexible member is present or on the opposite side. More specifically, the sheet portion 2 has a sheet-like sheet portion 2 on one side 2a (the side opposite to the side where the flexible member is present) on which the concave-convex structure 3 is provided, with protrusions 5 arranged in multiple rows extending linearly between the opposing longitudinal sides of the sheet portion 2. However, the concave-convex structure may also be provided on the surface 2b (the surface where the flexible member is present), which is the surface opposite to the surface 2a of the sheet portion, or may be provided on both of these surfaces. The uneven structure 3 is formed by arranging multiple uneven unit shapes 4, each of which is a linearly extending convex portion 5 on the surface of the sheet portion 2 and a concave portion 6, which is a flat portion adjacent to this convex portion 5, between the opposing short sides of the sheet portion 2. The sound-insulating structure 7 shown in Figure 9 is constructed by providing a flexible member 8 on the surface 2b of the sheet portion 2 on the side where the uneven structure 3 is not provided, and further providing an adherend 9 on one side surface 8b of the flexible member 8 on the side where the uneven sheet member 1 is not provided. The uneven structure 3 may be a linear uneven structure as shown in FIGS. 1 and 2, or may be a dot-shaped uneven structure as shown in FIG.

[0018] The sheet portion 2 according to this embodiment is used to support the protrusions 5. By providing a plurality of protrusions 5 on the sheet portion 2, convex portions and concave portions are created, thereby forming the concave-convex structure 3. The material forming the sheet portion 2 is not particularly limited as long as it can support the protrusions 5, and may be the same as or different from the material forming the protrusions 5. However, from the viewpoint of supporting the plurality of protrusions 5, it is preferable to use a material that is more rigid than the resin used to form the protrusions 5. Specifically, the sheet portion 2 preferably has a Young's modulus of 1 GPa or more, more preferably 1.5 GPa or more. There is no particular upper limit to the Young's modulus, but it may be, for example, 1000 GPa or less.

[0019] The surface density of the sheet portion 2 is set to 2.5 kg / m from the viewpoint of inducing a vibration mode effective for sound insulation in the sheet portion. 2 Less than or equal to 2.0 kg / m, more preferably 2.0 kg / m 2 From the viewpoint of the handling of the seat part, it is 0.06 kg / m or less. 2 It is preferable that this is equal to or greater than this.

[0020] Specific examples of materials constituting the sheet portion 2 include organic materials such as polyacrylonitrile, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyvinyl chloride, polyvinylidene chloride, polychlorotrifluoroethylene, polyethylene, polypropylene, polystyrene, cyclic polyolefin, polynorbornene, polyethersulfone, polyetheretherketone, polyphenylene sulfide, polyarylate, polycarbonate, polyamide, polyimide, triacetyl cellulose, polystyrene, epoxy resin, acrylic resin, or oxazine resin, or composite materials containing metals such as aluminum, stainless steel, iron, copper, zinc, or brass, inorganic glass, or inorganic particles or fibers in these organic materials, but are not particularly limited to these. Among these, polyethylene terephthalate is preferred from the viewpoints of sound insulation, rigidity, moldability, cost, and the like. The sheet portion 2 may be composed of one layer, or may be composed of two or more layers stacked together. In the case where the sheet portion 2 is composed of two or more layers stacked together, the conditions for the sheet portion 2 in this specification are those for the laminate, unless otherwise specified.

[0021] The thickness d of the sheet portion 2 is preferably 30 μm or more and 500 μm or less, more preferably 40 μm or more and 400 μm or less, and even more preferably 45 μm or more and 300 μm or less. When the thickness of the sheet portion 2 is 30 μm or more, it is easy to handle, and when it is 500 μm or less, the provision of the protrusions 5 improves the sound insulation performance. The area of ​​the sheet portion 2 needs to be equal to or greater than the area of ​​the area to be sound-insulated, in order to prevent incident sound from reaching the area to be sound-insulated without passing through the textured sheet.

[0022] The shape of the sheet portion 2 is not limited to the embodiment shown in Figures 1 and 2. It can be set appropriately depending on the installation surface of the uneven sheet member 1. For example, it may be a flat sheet, a curved sheet, or a special shape processed to have curved or bent portions. Furthermore, from the viewpoint of weight reduction, etc., cuts, punched portions, etc. may be provided at any location on the sheet portion 2.

[0023] When the sheet part 2 is used by being attached to the flexible member 8, the sheet part 2 may have an adhesive layer or the like on one or both surfaces 2a and 2b of the sheet part 2. Furthermore, the manufacturing method of the sheet portion 2 and the protrusions 5 is not particularly limited, and as described below, they may be molded as separate materials and then bonded together, or they may be molded as a single unit. However, when they are molded as separate materials and then bonded together, an adhesive layer may be provided at the adhesive portion between the sheet portion 2 and the protrusions 5 and / or at the adhesive portion between the protrusions 5 and the sheet portion 2.

[0024] The convex portions 5 constituting the concave-convex structure 3 serve to impart local (preferably local and periodic) rigidity and mass to the sheet portion 2. By imparting local (preferably periodic) rigidity and mass, a vibration mode corresponding to the distance between the convex portions is excited in the sheet portion 2 when sound waves are incident from a sound source.

[0025] The sound-insulating mechanism of the sound-insulating sheets having multiple cylindrical protrusions described in Patent Documents 3 and 4 is thought to be due to the fact that when sound waves are incident, each protrusion resonates in response to sound waves of a specific frequency, increasing the dynamic mass. On the other hand, it is thought that the vibration of the sheet portion 2 of the concave-convex sheet member 1 functions as the sound-insulating mechanism. That is, the protrusions 5 impart local (preferably local and periodic) rigidity and mass to the sheet portion 2, thereby exciting a vibration mode corresponding to the distance between the protrusions, and the vibration of the sheet portion 2 can exert a sound-insulating effect at a specific frequency.

[0026] Depending on the thickness of the sheet portion, the mass of the convex portions, etc., the shape of the concave-convex structure 3 is not limited to linear, and by making the convex portions cylindrical or dot-shaped, it is possible to effectively impart local (preferably local and periodic) rigidity and mass.

[0027] The method for forming the uneven structure 3 is not particularly limited, and it may be formed by deforming the sheet portion 2, for example, by pressing a mold having a cavity with an uneven structure against a sheet without an uneven structure to deform it, or by forming the protrusions 5 integrally with the sheet portion 2 using a material different from the sheet portion 2, for example, by pouring a raw material into a cavity with an uneven structure, or by producing the protrusions and the sheet portion separately and then bonding them with an adhesive material. Furthermore, the uneven structure 3 may be formed on one surface of the sheet portion 2, or may be formed on multiple surfaces, but the inventors believe that it is preferable to form it on one surface of the sheet portion 2 from the viewpoint of obtaining stable sound insulation.

[0028] The shape of a cross section perpendicular to the arrangement direction of the protrusions 5, i.e., the transverse cross section of the protrusions 5, can be roughly square, rectangular, trapezoid, semicircular, semielliptical, etc. The cross-sectional shape of the protrusions 5 can be appropriately selected depending on the application from the viewpoints of sound insulation performance, manufacturing costs, ease of handling, etc.

[0029] The maximum width w1max in a cross section perpendicular to the arrangement direction of the uneven unit shapes 4, i.e., the maximum width w1max of the transverse cross section of the convex portions 5, is preferably 0.5 mm to 10 mm, more preferably 0.7 mm to 8 mm, and even more preferably 1 mm to 6 mm. Within the above range, a thin, lightweight uneven sheet member 1 with excellent sound insulation performance in the low frequency band can be obtained.

[0030] The height of the uneven unit shapes 4, i.e., the height t of the protrusions 5, is preferably 0.5 mm to 10 mm, more preferably 0.7 mm to 8 mm, and even more preferably 1 mm to 6 mm. Within the above range, a thin, lightweight uneven sheet member 1 that has excellent sound insulation performance in the low frequency band can be obtained.

[0031] The spacing between the concave-convex unit shapes 4, i.e., the width (w2) of the recesses 6, is preferably 3 mm to 100 mm, more preferably 4 mm to 80 mm, and even more preferably 5 mm to 50 mm. Within the above range, a lightweight concave-convex sheet member 1 with excellent sound insulation performance in the low frequency band can be obtained.

[0032] In the sound-insulating structure 7 having the above-described configuration, it is preferable that the uneven sheet member 1 has a sheet portion 2 and a convex portion 5 protruding linearly from the sheet portion 2, and uneven unit shapes having the convex portion 5 and the concave portion 6 along the convex portion 5 are repeatedly arranged in one or two directions on the sheet portion 2, from the viewpoint of being able to obtain a high sound-insulating effect even against sound waves with a relatively low sound pressure.

[0033] Furthermore, when the specific gravity of the convex portion 5 is sg, it is preferable that the concave-convex structure 3 is formed such that the maximum width w1max (mm) of the cross section of the convex portion 5, the height t (mm) of the convex portion 5, and the width w2 (mm) of the concave portion 6 are within the ranges defined by the following formulas (I) and (II). 0.1≦ w1max×t×sg / w2 ≦ 10 (I) 5 ≦ w1max×t ≦ 50 (II) When producing the uneven sheet member 1, the optimum value for the configuration of the uneven unit shapes 4 that will provide high sound insulation performance varies depending on the relationship between the thickness d of the sheet portion 2 and the sizes of the convex portions 5 and concave portions 6, as described above, but the uneven sheet member 1 can provide good sound insulation as long as it is within the ranges defined by formula (I) above, which defines the surface density of the uneven unit shapes 4, and formula (II) above, which defines the cross-sectional area of ​​the convex portions 5. If it is below the lower limit of the range defined by both formulas, the sound insulation strength will decrease, and if it is above the upper limit, sound insulation performance in the low frequency band will not be obtained.

[0034] The weight ratio of the protrusions 5 to the sheet portion 2, expressed as (weight of the protrusions 5 / weight of the sheet portion 2), is preferably in the range of 0.1 to 50, more preferably 0.5 to 30, and even more preferably 0.7 or more. It is particularly preferably 1.0 to 20. Most preferably 2.0 or more. By setting the weight ratio of the protrusions 5 to the sheet portion 2 within this range, the protrusions 5 function more effectively as local (preferably local and periodic) rigidity and mass against vibrations of the sheet portion 2, thereby effectively increasing the sound insulation strength in the low frequency band. The soft material to which the uneven sheet is attached has a load of 160 kPa or less that gives a deformation rate of 4% in a compression test using a compression testing machine, so the specific vibrations of the uneven sheet are not suppressed, and sufficient sound insulation effect can be achieved.

[0035] When the weight ratio of the convex portion to the sheet portion, expressed as (weight of convex portion 5 / weight of sheet portion 2), is in the range of 5 or less, it is more important not to suppress the vibration of the uneven sheet, so in a compression test using a compression tester, it is preferable that the load giving a deformation rate of 4% is 10 kPa or less.

[0036] The area ratio of the convex portions 5 to the concave portions 6, expressed as (area of ​​convex portions 5 / area of ​​concave portions 6), is preferably in the range of 0.1 to 3, and more preferably 0.15 to 2.0. It is even more preferably 0.2 to 1.5. By setting the area ratio within this range, the convex portions 5 function more effectively as local rigidity and mass against vibrations of the sheet portion 2, thereby effectively increasing the sound insulation strength in the low frequency band. The area of ​​the convex portions is the area occupied by the convex portions relative to the entire sheet portion, and the area of ​​the concave portions is the area occupied by the concave portions relative to the entire sheet portion.

[0037] The protrusions 5 may be configured as a single structure, as shown in Figures 1 and 2, or as shown in Figure 3, they may be configured as a composite structure consisting of a base 5a protruding to an appropriate height and a weight 5b supported at the upper end of the base 5a and having a greater mass than the base 5a. Furthermore, as shown in Figure 4, the protrusions 5 may be configured as a composite structure in which the weight 5b is embedded within the base 5a. Such a composite structure increases the local rigidity and mass of the protrusions 5, thereby improving the low-frequency sound insulation of the concave-convex sheet member 1. Furthermore, the protrusions 5 may be porous, containing pores (gas such as air), as long as this does not result in a decrease in sound insulation. The material constituting the base portion 5a can be the material of the protrusions described below. The material for weight portion 5b may be appropriately selected taking into consideration mass, cost, etc., and may be, for example, a metal or alloy such as aluminum, stainless steel, iron, tungsten, gold, silver, copper, lead, zinc, or brass; inorganic glass such as soda glass, quartz glass, or lead glass; or a composite containing powder of these metals or alloys or these inorganic glasses in the resin material of base portion 5a. The material, mass, and specific gravity of weight portion 5b may be determined so as to match the desired sound insulation frequency range for sound-insulating structure 7.

[0038] The protrusions 5 may have a discontinuous structure in the longitudinal direction, where they are interrupted as appropriate. In addition, the multiple protrusions 5 are arranged in parallel, but they may not only be arranged in parallel, but may also be arranged at an appropriate angle to each other as long as they do not overlap.

[0039] 5, the uneven structure 3 may have rib-like protrusions 22 provided on the surface 2a of the sheet portion 2 of the uneven sheet member 1. The rib-like protrusions 22 are arranged in pairs on the edges of opposing shorter sides of the sheet portion 2, sandwiching a protrusion 5 therebetween. The upper surfaces of both rib-like protrusions 22 are parallel (or may be approximately parallel) to the surface 2a, and the rib-like protrusions 22 are arranged in the shape of rectangular plates extending parallel (or may be approximately parallel) to the protrusions 5. The rib-like protrusions 22 have a maximum height that is higher than the maximum height of the protrusions 5 in the normal direction of the sheet portion 2. When the sheet portion 2 is manufactured by so-called roll-to-roll production, for example, by cutting out from a long sheet material having the uneven structure 3 provided on one surface of the sheet portion 2, by aligning the axial direction (longitudinal direction) of the rib-like protrusions 22 with the longitudinal direction (sheet flow direction) of the sheet material, even when the uneven sheet member 1 is rolled up into a sheet or multiple sheets are stacked together, the rib-like protrusions 22 function as spacers, thereby preventing the protrusions 5 from coming into contact with the back surfaces of the stacked sheet portions 2. The provision of the rib-like protrusions 22 reduces the likelihood of manufacturing problems such as deformation, deviation, cracking, falling off, and breakage of the protrusions 5, making it easier to manufacture and store the uneven sheet member 1 by so-called roll-to-roll production.

[0040] The uneven sheet member 1 constituting the sound-insulating structure 7 may have a linear uneven structure 3 as shown in Figures 1 to 5, or an uneven structure 3 consisting of dot-shaped convex portions as shown in Figures 6 to 8.

[0041] The uneven sheet member 1 shown in Figures 6 to 8 has an uneven structure 3 in which a plurality of dot-shaped convex portions (also referred to as "protrusions" in the explanation of Figures 6 to 8) 51 are arranged vertically and horizontally at predetermined intervals as uneven unit shapes 4 on one side surface 2a of a sheet portion 2.

[0042] The protrusions 51 that make up the uneven structure 3 impart local rigidity and mass (preferably periodically) and function to excite a vibration mode in the sheet portion 2 corresponding to the distance between the protrusions, thereby achieving high sound insulation performance that exceeds the mass law when sound waves of a specific frequency are incident.

[0043] 6, the protrusions 51 may be configured as a single structure, or may be configured as a composite structure including a weight portion (not shown) if the placement of the weight portion does not cause any molding problems. The protrusions 51 may also be porous.

[0044] 7, rib-like protrusions 22 may be provided on the surface 2a of the base material 2 of the concave-convex sheet member 1. The rib-like protrusions 22 are not limited to a rectangular plate-like configuration. For example, as shown in FIG. 8, the rib-like protrusions 23 may be cylindrical, with a plurality of cylindrical rib-like protrusions 23 arranged at intervals on both edges in the first direction to form rows along the second direction. This configuration not only achieves the same effects as the rectangular plate-like rib-like protrusions 22 shown in FIG. 7, but also enhances the conformability (flexibility) of the concave-convex sheet member 1 by arranging the plurality of rib-like protrusions 23 at intervals. Therefore, the stretchable and flexible sheet member 2 can conform to the surface shape of an attachment surface with a more complex shape.

[0045] The concave-convex structure 3 has protrusions 51, which are unit shapes of concaves and convexes, and the protrusions 51 are repeatedly arranged in at least two different directions along the surface 2a of the sheet part 2 on the side of the concave-convex structure 3. In Figures 6 to 8, the protrusions 51 are arranged along orthogonal sides of the substrate 2, which is rectangular in plan view. The protrusions 51 may have roughly a cylindrical shape, a prismatic shape, a conical shape, a truncated conical shape, a pyramidal shape, a truncated pyramidal shape, a hemispherical shape, an ellipsoidal shape, or the like, which can be appropriately selected depending on the application from the viewpoints of sound insulation performance, manufacturing costs, handleability, and the like.

[0046] In the concave-convex structure 3, the ratio of the area of ​​the protrusions 51 to the area of ​​the surface 2a of the sheet portion 2 on the concave-convex structure 3 side is preferably 5 to 80% (5% or more and 80% or less), more preferably 5.5 to 70% (5.5% or more and 70% or less), and even more preferably 6 to 60% (6% or more and 60% or less). When the ratio is within the above range, sound insulation due to vibration of the sheet portion 2 is exhibited, and sound insulation is dramatically improved. The area of ​​the protrusions 51 is the cross-sectional area of ​​the protrusions 51 parallel to the sheet surface at the point where they connect with the surface 2a of the sheet portion 2.

[0047] In the concave-convex structure 3, it is preferable that the mass per protrusion 51 (per unit) is 20 mg or more and 900 mg or less, and the ratio of the area of ​​the protrusions 51 to the area of ​​the surface 2a (filling rate) is in the above range. In this case, the protrusions 51 play a role in imparting local (preferably local and periodic) rigidity and mass so that the sheet portion 2 vibrates in a mode effective for sound insulation when sound waves are incident from a noise source.

[0048] As described above, the mass of the protrusions 51 per unit shape is preferably 20 mg to 900 mg, more preferably 22 mg to 700 mg, even more preferably 24 mg to 600 mg, and particularly preferably 25 mg to 500 mg. When the mass of the protrusions 51 per unit shape is 20 mg to 900 mg, a vibration mode effective for sound insulation at a specific frequency is excited in the sheet portion 2 by imparting local (preferably local and periodic) rigidity and mass, and sound insulation performance is dramatically improved. do. The density of the protrusions 51 is set to 100 kg / m from the viewpoint of inducing a vibration mode effective for sound insulation in the sheet portion. 3 Preferably, it is 1000 kg / m or more. 3 It is more preferable that the load is 10,000 kg / m or more from the viewpoint of weight reduction. 3 It is preferable that the density is not more than 8000 kg / m 3 Less than 5000kg / m 3 may be less than 3000 kg / m 3It may be the following:

[0049] Furthermore, the maximum width of protrusion 51 in a cross section parallel to surface 2a (hereinafter simply referred to as "maximum width"), i.e., the diameter if protrusion 51 is cylindrical, or the maximum width across if protrusion 51 is prismatic, is preferably 0.5 mm to 50 mm, more preferably 1.0 mm to 30 mm, even more preferably 1.5 mm to 20 mm, and particularly preferably 2.0 mm to 10 mm. When protrusion 51 has a maximum width of 0.5 mm or more, it provides excellent sound insulation performance, and when it is 50 mm or less, it provides excellent formability and handleability.

[0050] Furthermore, the height (maximum height) of protrusions 51 is preferably 0.1 mm or more, 0.5 mm or more, and 50 mm or less, more preferably 0.7 mm or more and 30 mm or less, even more preferably 0.9 mm or more and 20 mm or less, and particularly preferably 1.2 mm or more and 10 mm or less. When the height of protrusions 51 is 0.5 mm or more, excellent sound insulation performance is achieved, and when it is 50 mm or less, excellent moldability and handleability are achieved.

[0051] Furthermore, the spacing between the protrusions 51 is preferably 1 mm or more and 100 mm or less, more preferably 1.4 mm or more and 80 mm or less, even more preferably 1.8 mm or more and 60 mm or less, and particularly preferably 2 mm or more and 50 mm or less. When the spacing between the uneven unit shapes is 1 mm or more, excellent formability is achieved, and when it is 100 mm or less, excellent sound insulation performance is achieved. The spacing between the uneven unit shapes is the distance (arrangement pitch) when a straight line is drawn between the center of one uneven unit shape and the center of an adjacent uneven unit shape.

[0052] The value of the mass per protrusion 51 relative to the thickness of the sheet portion 2 (mass per protrusion (mg / protrusion) / thickness of the sheet portion 2 (μm)) is preferably in the range of 0.4 to 4. When the protrusions 51 have a certain weight relative to the thickness of the base material 2, local (preferably local and periodic) rigidity and mass can be effectively imparted, thereby improving the sound insulation effect.

[0053] The number of protrusions 51 per unit area (proportion of the number) is preferably plural, specifically, 40 / m 2 More than 1000000 pieces / m 2 Less than 100 pieces / m, more preferably 2 More than 500000 pieces / m 2 Less than or equal to 300 particles / m 2 More than 100000 pieces / m 2 pieces / m 2 Below 500 pieces / m 2 More than 30000 pieces / m 2 pieces / m 2 Below 1000 pieces / m 2 More than 10000 pieces / m 2 pieces / m 2 It is preferable that the protrusions 51 are equal to or less than 1 / 2 in diameter. When a certain number of protrusions 51 are present, sound can be effectively blocked.

[0054] The type of material used to form the protrusions 5 is not particularly limited, and is preferably a material that has rubber elasticity and whose dynamic viscoelasticity can be measured, such as a resin or elastomer. Note that, although the conditions for the material of the sheet portion 2 have been described above, the following materials used to form the protrusions 5 may also be applied. Examples of resins include thermosetting or photocurable resins and thermoplastic resins, and examples of elastomers include thermosetting or photocurable elastomers and thermoplastic elastomers. Among these, photocurable resins or photocurable elastomers are preferred, and photocurable resins are particularly preferred because of their excellent shape transferability and excellent sound insulation properties. When a thermosetting or thermoplastic resin or a thermosetting or thermoplastic elastomer is used as the material for the protrusions 5, a curing reaction due to heat is required during molding of the protrusions 5, which tends to result in the formation of bubbles in the molded protrusions 5. If bubbles form, the sound insulation performance will be reduced. On the other hand, when a photocurable resin or a photocurable elastomer is used as the material for the protrusions 5, the problem of bubbles as described above does not occur, and therefore the sound insulation performance is less likely to be reduced. The resin or elastomer may be used as a single material, or as a mixture of two or more materials in any combination and ratio. However, from the viewpoint of being able to control properties such as storage modulus and tensile elongation at break, it is preferable to combine two or more materials.

[0055] Examples of resins used to form the convex portions 5 include thermosetting resins such as unsaturated polyester resin, phenol resin, epoxy resin, urethane resin, or rosin-modified maleic acid resin; photocurable resins such as homopolymers or copolymers of monomers such as epoxy(meth)acrylate, urethane(meth)acrylate, polyester(meth)acrylate, polyether(meth)acrylate, or modified versions thereof; homopolymers or copolymers of vinyl monomers such as vinyl acetate, vinyl chloride, vinyl alcohol, vinyl butyral, or vinylpyrrolidone; and thermoplastic resins such as saturated polyester resin, polycarbonate resin, polyamide resin, polyolefin resin, polyarylate resin, polysulfone resin, or polyphenylene ether resin. Among these, urethane(meth)acrylate, polyester(meth)acrylate, or polyether(meth)acrylate, which have a low elastic modulus when cured, are preferred, and urethane(meth)acrylate is particularly preferred.

[0056] Examples of elastomers used to form the convex portions 5 include thermosetting elastomers such as vulcanized rubbers, such as chemically crosslinked natural rubber or synthetic rubber, and thermosetting resin-based elastomers, such as urethane rubber, silicone rubber, fluororubber, and acrylic rubber; thermoplastic elastomers, such as olefin-based thermoplastic elastomers, styrene-based thermoplastic elastomers, vinyl chloride-based thermoplastic elastomers, urethane-based thermoplastic elastomers, ester-based thermoplastic elastomers, amide-based thermoplastic elastomers, silicone rubber-based thermoplastic elastomers, and acrylic-based thermoplastic elastomers; photocurable elastomers, such as acrylic photocurable elastomers, silicone photocurable elastomers, and epoxy photocurable elastomers; silicone-based thermosetting elastomers; acrylic thermosetting elastomers; and epoxy-based thermosetting elastomers. Among these, silicone-based thermosetting elastomers and acrylic thermosetting elastomers, which are thermosetting elastomers, and acrylic photocurable elastomers and silicone photocurable elastomers, which are photocurable elastomers, are preferred.

[0057] Photocurable resins are resins that polymerize upon irradiation with light. Examples include photoradical polymerizable resins and photocationic polymerizable resins. Among these, photoradical polymerizable resins are preferred. The photoradical polymerizable resin preferably has at least one (meth)acryloyl group in the molecule. The photoradical polymerizable elastomer having one or more (meth)acryloyl groups in the molecule is not particularly limited, but from the viewpoint of the elastic modulus of the cured product, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-methylbutyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, 2-methylhexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, acrylate, 2-butylhexyl (meth)acrylate, isooctyl (meth)acrylate, isopentyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, phenoxy (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, lauryl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, morpholin-4-yl (meth)acrylate, or urethane (meth)acrylate, etc. Among these, urethane (meth)acrylate is preferred from the viewpoint of the elastic modulus of the cured product.

[0058] Furthermore, the resin used to form the convex portions 5 may contain a compound having an ethylenically unsaturated bond. Examples of compounds having an ethylenically unsaturated bond include aromatic vinyl monomers such as styrene, α-methylstyrene, α-chlorostyrene, vinyltoluene, and divinylbenzene; vinyl ester monomers such as vinyl acetate, vinyl butyrate, N-vinylformamide, N-vinylacetamide, N-vinyl-2-pyrrolidone, N-vinylcaprolactam, and divinyl adipate; vinyl ethers such as ethyl vinyl ether and phenyl vinyl ether; allyl compounds such as diallyl phthalate, trimethylolpropane diallyl ether, and allyl glycidyl ether; (meth)acrylamides such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, Nt-butyl(meth)acrylamide, (meth)acryloylmorpholine, and methylenebis(meth)acrylamide; (meth)acrylic acid, methyl(meth)acrylate, ethyl(meth)acrylate, and (meth)acrylic acid. Propyl, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, morpholyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycidyl (meth)acrylate, dimethicone mono(meth)acrylates such as ethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, phenoxyethyl (meth)acrylate, tricyclodecane (meth)acrylate, dicyclopentenyl (meth)acrylate, allyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, isobornyl (meth)acrylate, or phenyl (meth)acrylate; ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate,Triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate (number of repeating units: 5 to 14), propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate (number of repeating units: 5 to 14), 1,3-butylene glycol di(meth)acrylate, 1,4- Butanediol, polybutylene glycol di(meth)acrylate (number of repeating units: 3-16), poly(1-methylbutylene glycol) di(meth)acrylate (number of repeating units: 5-20), 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, neopentyl glycol hydroxypivalate di(meth)acrylic acid ester, di(meth)acrylate of dicyclopentanediol, caprolactone adduct of neopentyl glycol hydroxypivalate Di(meth)acrylic acid esters of (n+m=2-5), di(meth)acrylic acid esters of γ-butyrolactone adducts of neopentyl glycol hydroxypivalate (n+m=2-5), di(meth)acrylic acid esters of caprolactone adducts of neopentyl glycol (n+m=2-5), di(meth)acrylic acid esters of caprolactone adducts of butylene glycol (n+m=2-5), di(meth)acrylic acid esters of caprolactone adducts of cyclohexanedimethanol (n+m=2-5), caprolactone of dicyclopentanediol Di(meth)acrylic acid esters of adducts (n+m=2-5), di(meth)acrylic acid esters of caprolactone adducts of bisphenol A (n+m=2-5), di(meth)acrylic acid esters of caprolactone adducts of bisphenol F (n+m=2-5), di(meth)acrylic acid esters of ethylene oxide adducts of bisphenol A (p=1-7), di(meth)acrylic acid esters of propylene oxide adducts of bisphenol A (p=1-7), di(meth)acrylic acid esters of ethylene oxide adducts of bisphenol F (p=1-7),Di(meth)acrylate of bisphenol F propylene oxide adduct (p=1-7), trimethylolpropane tri(meth)acrylate, trimethylolpropane ethylene oxide adduct (p=1-5) tri(meth)acrylate, trimethylolpropane propylene oxide adduct (p=1-5) tri(meth)acrylate, glycerin tri(meth)acrylate, glycerin ethylene oxide adduct (p=1-5) tri(meth)acrylate, ditrimethylolpropane tetra( meth)acrylic acid ester, tetra(meth)acrylic acid ester of ditrimethylolpropane ethylene oxide adduct (p=1-5), pentaerythritol tri(meth)acrylic acid ester, pentaerythritol tetra(meth)acrylic acid ester, tri(meth)acrylic acid ester of pentaerythritol ethylene oxide adduct (p=1-5), tetra(meth)acrylic acid ester of pentaerythritol ethylene oxide adduct (p=1-15), tri(meth)acrylic acid ester of pentaerythritol propylene oxide adduct (p=1-5) ) acrylate ester, tetra(meth)acrylate ester of pentaerythritol propylene oxide adduct (p=1-15), penta(meth)acrylate ester of dipentaerythritol ethylene oxide adduct (p=1-5), hexa(meth)acrylate ester of dipentaerythritol ethylene oxide adduct (p=1-15), poly(meth)acrylate such as N,N',N"-tris((meth)acryloxypoly(p=1-4)(ethoxy)ethyl)isocyanurate with pentaerythritol caprolactone (4-8 moles) tri(meth)acrylates of pentaerythritol caprolactone (4 to 8 mol) adducts, tetra(meth)acrylates of pentaerythritol caprolactone (4 to 8 mol) adducts, dipentaerythritol penta(meth)acrylates, dipentaerythritol hexa(meth)acrylates, penta(meth)acrylates of dipentaerythritol caprolactone (4 to 12 mol) adducts, hexa(meth)acrylates of dipentaerythritol caprolactone (4 to 12 mol) adducts, N,N',N"-tris(acryloxyethyl) isocyanurate,Polyfunctional (meth)acrylates such as N,N'-bis(acryloxyethyl)-N"-hydroxyethyl isocyanurate, ethylene oxide isocyanurate modified (meth)acrylate, propylene oxide isocyanurate modified (meth)acrylate, or ethylene oxide / propylene oxide isocyanurate modified (meth)acrylate; or bisphenol A glycidyl ether, bisphenol F glycidyl ether, phenol novolac epoxy resin, cresol novolac epoxy resin, pentaerythritol polyglycidyl ether, trimethylolpropane triglycidyl ether, or Examples include epoxy poly(meth)acrylates obtained by the addition reaction of a polyepoxy compound having multiple epoxy groups in the molecule, such as triglycidyl tris(2-hydroxyethyl)isocyanurate, with (meth)acrylic acid. Among these, phenoxyethyl acrylate, benzyl acrylate, 2-ethylhexyl (meth)acrylate, and methoxypolyethylene glycol acrylate are preferred, as they give a cured product with a low elastic modulus, and 2-ethylhexyl (meth)acrylate and methoxypolyethylene glycol acrylate are more preferred. These can be used alone or in combination of two or more.

[0059] The content of the resin and / or elastomer used to form the protrusions 5 can be adjusted appropriately from the viewpoints of sound insulation performance, manufacturing costs, other functions, etc., and is not particularly limited, and when the mass of the material constituting the protrusions 5 is taken as 100 mass%, the content is, for example, usually 70 mass% or more, preferably 80 mass% or more. Alternatively, it may be 100 mass%, but is preferably 99 mass% or less.

[0060] When the projections 5 are formed using a photocurable resin or elastomer, the moldability and mechanical strength are improved. From the viewpoint of reducing production costs, it is preferable to contain a photopolymerization initiator, and examples of such photopolymerization initiators include benzoin-based, acetophenone-based, thioxanthone-based, phosphine oxide-based, and peroxide-based photopolymerization initiators. Specific examples of the photopolymerization initiator include benzophenone, 4,4-bis(diethylamino)benzophenone, 2,4,6-trimethylbenzophenone, methyl orthobenzoylbenzoate, 4-phenylbenzophenone, t-butylanthraquinone, 2-ethylanthraquinone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, benzyl dimethyl ketal, 1-hydroxycyclohexyl-phenyl ketone, benzoin methyl ether, and benzyl dimethyl ketal. Examples of such a benzoin include benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, diethylthioxanthone, isopropylthioxanthone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and methylbenzoyl formate. These may be used alone or in any combination and ratio of two or more.

[0061] The content of the photopolymerization initiator in the resin used to form the convex portions 5 is not particularly limited, but from the viewpoint of improving mechanical strength and maintaining an appropriate reaction rate, when the mass of the material constituting the concave-convex structure 3 is taken as 100 mass%, it is usually 0.1 mass% or more, preferably 0.3 mass% or more, and more preferably 0.5 mass% or more. Also, it is usually 3 mass% or less, preferably 2 mass% or less.

[0062] The resin used to form the protrusions 5 may contain particles, plates, spheres, etc. to improve sound insulation and other functions. These materials are not particularly limited, and examples include metal, inorganic, and organic materials. The protrusions 5 may contain inorganic fine particles from the viewpoint of improving mechanical strength and reducing material costs. Examples of such inorganic fine particles include transparent inorganic fine particles such as silicon oxide, aluminum oxide, titanium oxide, soda glass, and diamond. In addition to such inorganic fine particles, resin particles such as acrylic resin, styrene resin, silicone resin, melamine resin, epoxy resin, or copolymers thereof can also be used as the fine particles.

[0063] The resin used to form the convex portion 5 may contain various additives such as flame retardants, antioxidants, plasticizers, antifoaming agents, or release agents as other components, as long as the sound insulation performance is not impaired. These may be used alone or in combination of two or more. Flame retardants are additives that are blended into flammable materials to make them less flammable or to prevent them from igniting. Specific examples include, but are not limited to, bromine compounds such as pentabromodiphenyl ether, octabromodiphenyl ether, decabromodiphenyl ether, tetrabromobisphenol A, hexabromocyclododecane, and hexabromobenzene, phosphorus compounds such as triphenyl phosphate, chlorine compounds such as chlorinated paraffins, antimony compounds such as antimony trioxide, metal hydroxides such as aluminum hydroxide, nitrogen compounds such as melamine cyanurate, and boron compounds such as sodium borate. The antioxidant is an additive that is blended to prevent oxidative degradation, and specific examples thereof include, but are not limited to, phenol-based antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants. Plasticizers are additives that are added to improve flexibility and weather resistance. Examples of the oil include, but are not limited to, phthalates, adipates, trimellitates, polyesters, phosphates, citrates, sebacates, azelates, maleates, silicone oils, mineral oils, vegetable oils, and modified products thereof.

[0064] (Method for forming concave-convex sheet member) The molding method for the concave-convex sheet member 1 is not particularly limited, and a commonly known sheet molding method can be used. In the case of a thermosetting or thermoplastic resin or elastomer, examples include melt molding methods such as press molding, extrusion molding, and injection molding. In this case, the molding conditions, such as the temperature and pressure, used for melt molding can be appropriately changed depending on the type of material used. In the case of a photocurable resin or elastomer, for example, the resin can be injected into a plate-shaped mold that is transparent to active energy rays and then photocured by irradiating it with active energy rays.

[0065] The active energy rays, which are specific rays used to cure photocurable resins, may be any rays capable of curing the photocurable resins used, such as ultraviolet rays and electron beams. The amount of active energy rays irradiated may be any amount sufficient to cure the photocurable resins used. Taking into consideration the types and amounts of monomers and polymerization initiators, for example, ultraviolet rays with a wavelength of 200 to 400 nm are typically irradiated at a dose in the range of 0.1 to 200 J. Examples of light sources for active energy rays include chemical lamps, xenon lamps, low-pressure mercury lamps, high-pressure mercury lamps, and metal halide lamps. While the active energy rays may be irradiated in a single step, it is preferable to irradiate the photocurable resin sheet in multiple steps, preferably at least two steps, to obtain a photocurable resin sheet with good surface properties. When a photocurable resin is used, a curing accelerator may be added.

[0066] Furthermore, the method for forming the protrusions 5 on the sheet portion 2 is not particularly limited, and may be a method in which the sheet portion 2 and the protrusions 5 are simultaneously formed using a mold having a cavity with a concave-convex structure, or a method in which the sheet portion 2 and the protrusions 5 are formed by combining them. Below, a method in which the sheet portion 2 and the protrusions 5 are formed by combining them will be described in detail, but the method is not limited to this method.

[0067] The method for combining the sheet portion 2 and the protrusions 5 is not particularly limited, and may be either a method of forming the protrusions 5 on the sheet portion 2 or a method of bonding the molded protrusions 5 to the sheet portion 2. In the bonding method, it is preferable to use an adhesive, but there is no limitation on the type of adhesive as long as it can bond the protrusions 5 to the sheet portion 2.

[0068] Next, an example of an embodiment for molding the concave-convex sheet member 1 using a thermosetting resin will be described. Fig. 11 shows a schematic cross-sectional end surface of an example mold used for molding the concave-convex sheet member 1. The illustrated mold 16 has concave-convex portions formed on its upper surface that correspond to the external shape of the concave-convex structure 3 of the concave-convex sheet member 1, i.e., a plurality of cavities (concave grooves) 16a formed by recessing the surface into groove shapes that correspond to the external shape of the convex portions 5.

[0069] The mold 16 can be used to mold the concave-convex sheet member 1 in the following manner. First, the mold 16 is set with the side on which the cavities 16a are formed facing upward. Photocurable resin is poured into each of the cavities 16a to fill them. A sheet portion 2 made of a material that transmits specific light rays, such as ultraviolet light or an electron beam, that cure the photocurable resin is then placed on top of the mold 16. Next, with the sheet portion 2 pressed against the top surface of the mold 16, specific light rays are irradiated from above to cure the photocurable resin in the cavities 16a through the sheet portion 2 and fix it to the surface of the sheet portion 2. Once the photocurable resin has hardened, the sheet portion 2 with the convex portions 5 fixed to its surface can be peeled from the mold 16 as shown in FIG. 12 to obtain a concave-convex sheet member 1 having a concave-convex structure 3 formed on the surface of the sheet portion 2.

[0070] FIG. 13 also shows a roll-to-roll molding method for forming a long sheet-like sheet member 1 using a photocurable resin and a material that transmits specific light rays that cure the photocurable resin. As shown in FIG. 13(A), a cylindrical roll-like mold 17 is used for molding. The mold 17 has a peripheral surface formed with multiple cavities 17a, which are groove-shaped depressions in the surface along the circumferential direction and correspond to the external shapes of the protrusions 5. The long sheet-like sheet member 2 is fed from a sheet feeder (not shown) that supports a roll of the sheet 2 around which the sheet 2 is wound. As shown in FIG. 13(B), the sheet is compressed and wound around the peripheral surface of the mold 17 under tension by a compression roll 18 and a compression roll 19, which are located upstream and downstream of the conveyance, respectively. The sheet 2 that passes through the compression roll 19 is then wound up by a sheet winding device (not shown). A nozzle 20 for supplying photocurable resin is disposed above the pressure bonding roll 18 so that the resin supplied from the nozzle 20 flows into and fills the cavity 17a of the mold 17, and a plurality of light sources 21 for irradiating specific light rays are disposed below the mold 17 so that the specific light rays are irradiated onto the photocurable resin filled in the cavity 17a through the sheet portion 2 to cause it to harden. The mold 17 is disposed so as to rotate in synchronization with the sheet conveying speed of the sheet supply means and the sheet winding means.

[0071] In this embodiment, the concave-convex sheet member 1 can be formed by the following procedure. First, the leading end of the long sheet-like sheet portion 2 is fed from a sheet supply means and wound around the circumferential surface of a mold 17, and is also wound around pressure rolls 18 and 19 to apply tension, and the leading end of the sheet portion 2 is attached to a sheet winding means. Next, the sheet portion 2 is supplied from the sheet supply means and wound up by the sheet winding means, while being wound around the rotating mold 17. At the same time, a photocurable resin is discharged from a nozzle 20 to fill the cavity 17a of the mold 17 with the photocurable resin. As the sheet portion 2 wound around the mold 17 is rotated and transferred together with the mold 17 toward the pressure rolls 19, a specific light beam is irradiated onto the surface of the sheet portion 2 from a light source 21 disposed below the mold 17. The specific light beam is irradiated through the sheet portion 2 onto the photocurable resin in the cavity 17a, causing the photocurable resin to harden and adhere to the surface of the sheet portion 2. The transfer speed of the sheet portion 2 wound around the mold 17 (the rotation speed of the mold 17) is set so that the photocurable resin in the cavities 17a is completely cured by receiving specific light rays irradiated from the light source 21 while the sheet portion 2 is wound around the mold 17. The sheet portion 2 is then peeled from the mold 17 via a pressure roller 19, and the sheet portion 2 with the convex portions 5 fixed to its surface is taken up by a sheet take-up means, thereby continuously forming a long, concave-convex sheet member 1. The taken-up sheet portion 2 is cut to dimensions appropriate for the installation location, thereby obtaining a concave-convex sheet member 1 of a desired size with the concave-convex structure 3 formed on the surface of the sheet portion 2. The cavities 16a, 17a formed in the mold 16 and the mold 17 are linearly formed along the outer shape of the convex portions 5, so that the resin flows evenly along the cavities 16a, 17a, and it is difficult for air bubbles to enter the cavities 16a, 17a along with the resin.

[0072] When producing the textured sheet member 1 in the manner described above with reference to Figures 11 to 13, a convex-shaped member can be provided on the sheet supplied to the roll, or a member having a textured structure can be provided on the sheet supplied to the roll. In the former case, the textured sheet member 1 produced has a structure consisting of a sheet portion 2 made of the sheet supplied to the roll and a convex portion 5 formed by roll-to-roll processing. In the latter case, the textured sheet member 1 produced has a structure consisting of a sheet portion 2 made of two layers, one made of the sheet supplied to the roll and one formed by roll-to-roll processing, and a convex portion 5 formed by roll-to-roll processing. In this embodiment, for example, the material described above in the description of the sheet portion can be used as the material for the sheet supplied to the roll, and the material described above in the description of the convex portion can be used as the material for the sheet and / or the convex portion formed by roll-to-roll processing.

[0073] [Soft material] The sound-insulating structure 7 has a flexible member 8. The flexible member 8 is provided on an adherend 9 and is sandwiched between the adherend 9 and the concave-convex sheet member 1. The shape of the flexible member 8 is not particularly limited as long as it can be provided so as to be disposed between the concave-convex sheet member 1 and the adherend, but it is preferably sheet-like. Regarding the method of attaching the flexible member 8 to the adherend 9, as described above, an adhesive layer or the like may be provided between the concave-convex sheet member 1 and the flexible member 8. The concave-convex sheet member 1 may be attached to the flexible member 8 with a pressure-sensitive adhesive, adhesive, double-sided tape, or gummed tape, or may be physically fixed with a tacker or stapler. Adhering the concave-convex sheet and the flexible member with an adhesive layer is preferable because it eliminates the need for any additional structure to maintain the structure. From the viewpoint of adhesive strength, the storage modulus of the adhesive layer is preferably 0.05 MPa or more. Alternatively, the two members may be in close contact with each other without being fixed. The concave-convex surface of the concave-convex sheet member 1 may be oriented toward the flexible member, and the flexible member 8 may be disposed on both sides of the sheet portions 2a and 2b of the concave-convex sheet member 1.

[0074] The flexible member 8 is disposed at least between the concave-convex sheet member 1 and the adherend 9, and functions to prevent the vibration of the sheet portion 2 of the concave-convex sheet member 1 from being inhibited by contact with the adherend 9. For the flexible member 8, it is preferable to use a material that can easily deform and follow the vibration displacement of the sheet portion, so as not to interfere with the vibration even when it comes into contact with the sheet portion 2 of the concave-convex sheet 1. Specifically, it is preferable that the load that gives the flexible member 8 a deformation rate of 4% in a compression test be 160 kPa or less, and even more preferably 120 kPa or less, so as to obtain a high sound insulation effect even against sound waves with a relatively low sound pressure. The material is not particularly limited as long as it satisfies this value, but examples include fiber-based sound-absorbing materials made of polymers or inorganic fibers, such as glass wool, rock wool, felt, blankets, or nonwoven fabrics; urethane, various rubbers; polymer foams such as polyethylene, polystyrene, or polypropylene; inorganic porous materials; metal foams; or porous materials obtained by solidifying and molding crushed or fiber waste materials thereof with various binders. These materials can be used alone or in combination. Among these, nonwoven fabrics, foams such as polymer foams or metal foams, glass wool, felt, or blankets are preferred, with nonwoven fabrics or foams being particularly preferred. These materials may be used alone or in any combination of two or more. Furthermore, while it is preferable that the flexible member be soft as described above so as not to interfere with the vibration of the concave-convex sheet, the load that gives a deformation rate of 4% in a compression test is preferably 0.15 kPa or more in order to maintain the strength of the structure. This is because by providing strength to the flexible member, it is possible to eliminate the need for members other than the flexible member to maintain strength, which is preferable from the perspective of installation and manufacturing.

[0075] The compression test is carried out according to the following method. A compression test is carried out to measure the hardness of the flexible member using a compression tester (for example, Brookfield's Texture Analyzer CT3-4500 compression tester). A load is applied perpendicular to the thickness direction of the flexible member at a speed of 0.1 mm / s using an acrylic cylindrical probe with a diameter of 12.7 mm and a height of 35 mm, and the deformation rate and load are measured. The surface of the flexible member to which the load is applied is larger than the area of ​​the bottom surface of the cylindrical probe and is flat.

[0076] The thickness of the flexible member 8 is preferably 0.2 μm or more and 100 mm or less, more preferably 0.5 μm or more and 50 mm or less, and even more preferably 1 μm or more and 30 mm or less, from the viewpoint of not hindering the vibration of the sheet portion of the uneven sheet and preventing the size from increasing.

[0077] [Adherend] The sound-insulating structure 7 has an adherend 9 on which the above-mentioned flexible member 8 is placed (adhered). The adherend 9 is placed on the surface of the flexible member 8 opposite to the side on which the concave-convex sheet member 1 is present. The material constituting the adherend 9 is not particularly limited as long as it can support the flexible member 8 on which the concave-convex sheet member 1 is provided.

[0078] Specific examples of materials constituting the adherend 9 include organic materials such as polyacrylonitrile, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyvinyl chloride, polyvinylidene chloride, polychlorotrifluoroethylene, polyethylene, polypropylene, polystyrene, cyclic polyolefins, polynorbornene, polyethersulfone, polyetheretherketone, polyphenylene sulfide, polyarylate, polycarbonate, polyamide, polyimide, triacetyl cellulose, polystyrene, epoxy resin, acrylic resin, or oxazine resin, or composite materials containing metals such as aluminum, stainless steel, iron, copper, zinc, or brass, inorganic glass, inorganic particles, or fibers in these organic materials, but are not limited thereto. Among these, from the viewpoints of sound insulation, rigidity, formability, cost, etc., the adherend 9 is preferably at least one selected from the group consisting of a photocurable resin sheet, a thermosetting resin sheet, a thermoplastic resin sheet, a metal plate, or an alloy plate.

[0079] The thickness and surface density of the adherend 9 are not particularly limited, but from the viewpoints of sound insulation performance, rigidity, formability, weight reduction, cost, etc., the thickness is usually preferably 0.01 mm or more and 50 mm or less, more preferably 0.05 mm or more and 25 mm or less, and even more preferably 0.1 mm or more and 10 mm or less, and the surface density is 2.0 kg / m 2 It is preferable that the density is 1.5 kg / m or less, and more preferably 1.5 kg / m 2 Less than 0.5 kg / m is preferable, usually 2 That's all. The effect of the present invention is to obtain a high sound insulation effect even when the concave-convex sheet member 1 is installed on a highly rigid member, and for example, the above effect can be obtained even when the adherend has a Young's modulus of 1 GPa or more. There is no particular upper limit to the Young's modulus, but it can be, for example, 1000 GPa or less.

[0080] The shape of the adherend 9 is not particularly limited and can be set appropriately depending on the installation surface of the flexible member 8. For example, it may be a flat sheet, a curved sheet, or a special shape processed to have curved or bent portions. Furthermore, from the viewpoint of weight reduction, etc., it may be provided with cuts or punched portions.

[0081] [Other materials] The sound-insulating structure 7 may include other components (other members) in addition to the above-described uneven sheet member 1, flexible member 8, and adherend 9, as long as the effects of the present invention are obtained, such as heat insulating materials, non-combustible materials, etc. The other components may be disposed between the uneven sheet member 1 and the flexible member 8, etc.

[0082] Another embodiment of the present invention is a sound-insulating sheet having at least a concave-convex sheet member and a soft member, specifically, a concave-convex sheet member having a concave-convex structure provided with a sheet portion and a plurality of convex portions provided on a surface of the sheet portion; a flexible member provided on the uneven sheet, The soft member has a load of 160 kPa or less that gives a deformation rate of 4% in a compression test using a compression tester, The embossed sheet is a sound-insulating sheet in which the weight ratio of the convex portions to the sheet portion, expressed as (weight of the convex portions / weight of the sheet portion), is 0.7 or more. In this specification, a sound-insulating sheet refers to a member having a concave-convex sheet member and a flexible member. The conditions and characteristics of the sound-insulating sheet according to this embodiment, the components constituting the sound-insulating sheet, and other components can be similarly applied to the conditions and characteristics of the sound-insulating sheet member, the components constituting the sound-insulating sheet member, and other components in the sound-insulating structure described above. In other words, the sound-insulating sheet according to this embodiment can be treated as the sound-insulating structure described above excluding the adherend element. Note that the sound-insulating sheet according to this embodiment may also include the adherend described above. In this case, the sound-insulating structure can have an adherend on which the soft member is placed, and the soft member can be disposed between the adherend and the concave-convex sheet member.

[0083] <2. Manufacturing method of sound insulation structure> There are no particular limitations on the method for manufacturing the sound-insulating structure 7. For example, the sound-insulating structure 7 can be manufactured by adhering the flexible member 8, via an adhesive or the like, to the surface of the uneven sheet member 1 that does not have the uneven structure 3, and further adhering an adherend, via an adhesive or the like, to the surface of the flexible member 8 opposite to the surface that is adhered to the uneven sheet member 1. The uneven sheet member 1 can be produced by molding the convex portions 5 and the sheet portion 2 separately and then bonding them together with an adhesive or the like, or by integrally molding the convex portions 5 and the sheet portion 2 using a mold having a cavity of the uneven structure 3. The flexible member 8 can be produced by a known method, or a commercially available product may be used. Furthermore, when molding the uneven sheet member 1, the resin or other raw material of the uneven sheet member 1 is hardened while in contact with the flexible member, thereby making it possible to bond the uneven sheet member 1 and the flexible member 8 without using an adhesive material such as an adhesive.

[0084] <3. Characteristics of sound insulation structures> [Sound insulation properties] To evaluate the sound insulation properties of the sound insulation structure, sound transmission loss was measured. The conditions for measuring sound transmission loss are shown below. When white noise was generated in one of two spaces separated by a sound-insulating structure, the sound transmission loss (TL) was calculated based on the following formula (1) from the difference in sound pressure level at a specified location in the space where the sound was generated (the sound source room) and the sound pressure level at a specified location in the other space (the sound receiving room) at each center frequency in the 1 / 12 octave band from 72.8 Hz to 10,900 Hz.

[0085]

number

[0086] It is preferable that the sound insulating structure 7 simultaneously satisfies the conditions represented by the following formulas (A) to (C). Satisfaction of the following conditions means that a high sound insulating effect can be obtained by installing the sound insulating structure in a desired direction. (TL1-TL2)-(TL3-TL4)>3dB ···(A) TL1-TL2>0dB (B) TL3-TL4>0dB (C) TL1 (dB): Sound transmission loss of a sound insulation structure when the uneven sheet member is installed facing the sound source TL2 (dB): Sound transmission loss of a sound insulation structure when the textured sheet is replaced with a flat sheet with the same mass and area under the condition of TL1. TL3 (dB): Sound transmission loss of a sound insulation structure when the adherend is placed facing the sound source TL4 (dB): Sound transmission loss of a sound insulation structure when the textured sheet is replaced with a flat sheet with the same mass and area under the condition of TL3. The TL1 and TL2 are sound transmission losses at the frequency when TL1-TL2 is maximum, and the TL3 and TL4 are sound transmission losses at the frequency when TL3-TL4 is maximum. Generally, the frequency at which TL1-TL2 is maximum is the frequency at which the largest peak value (maximum value of the peak) is obtained in a graph obtained by plotting frequency on the horizontal axis and TL1-TL2 on the vertical axis, and the frequency at which TL3-TL4 is maximum is the frequency at which the largest peak value (maximum value of the peak) is obtained in a graph obtained by plotting frequency on the horizontal axis and TL3-TL4 on the vertical axis. The peak values ​​in the examples refer to these peak values. When the conditions of the above formulas (A) to (C) are satisfied, the value of the left side of the above formula (A) is preferably greater than 3, more preferably greater than 4, even more preferably greater than 5, particularly preferably greater than 7, even more particularly preferably greater than 8, and most preferably greater than 10, from the viewpoint of increasing the effect of improving the sound insulation performance obtained by controlling the installation orientation of the sound insulation structure. As a method for satisfying the above formula (A), for example, a method is provided in which a concave-convex sheet member having long rectangular parallelepiped convex portions 4 made of urethane acrylate, each having a width of 6 mm, a height of 5 mm, and a pitch of 20 mm, arranged in one direction on a PET substrate having a thickness of 250 μm, is coated with an ultrafine acrylic fiber XAI (registered trademark) (basis weight 1000 g / m 2 One example of a method for producing a sound-insulating structure is to attach each side of the uneven sheet member to a sheet (25 mm thick) using double-sided tape, and then attach the opposite sides of the uneven sheet member to the surface of an adherend 9 made of a 0.6 mm thick steel plate. Satisfying the conditions of the above formulas (A) to (C) indicates that a high sound insulation effect can be obtained by installing the sound insulation structure in the desired direction. Furthermore, by applying this technology to conventional sound insulation materials, it is expected that the sound insulation characteristics obtained with conventional sound insulation materials will be improved. [Example]

[0087] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention. Note that the various conditions and values ​​of the evaluation results in the examples indicate preferred ranges of the present invention, similar to the preferred ranges in the above-described embodiments of the present invention. The preferred ranges of the present invention can be determined by taking into consideration the preferred ranges in the above-described embodiments and the values ​​in the following examples or the ranges indicated by a combination of values ​​between the examples.

[0088] Example 1 The raw materials were weighed out so that the mass ratio was EBECRYL230 (manufactured by Daicel-Allnex Corporation, urethane acrylate, weight-average molecular weight Mw: 5000) / Aronix M-120 (manufactured by Toagosei Co., Ltd., special acrylate) / IRGACURE 184 (manufactured by BASF, 1-hydroxycyclohexylphenyl ketone) / IRGACURE.TPO (manufactured by BASF, 2,4,6-trimethylbenzoyldiphenylphosphine oxide) = 50 / 50 / 1 / 0.1, and the mixture was stirred using a foam removal mixer (manufactured by Thinky Corporation, AR-250) for 20 minutes and degassed for 10 minutes to obtain mixture BL. As shown in Figures 11 to 13, the mixture BL was poured into an A4 size mold 16 made of aluminum and having recessed groove shapes (cavities) with a width of 6 mm and a height of 5 mm arranged in one direction at a pitch of 20 mm. Then, a sheet of 250 μm thick, 100% polyethylene terephthalate (PE) with a Young's modulus of 1.5 mm was placed on the mold as the material for the sheet portion 2. Approximately 4GPa, specific gravity 1.4, areal density 0.175kg / m 2 The PET film was placed on the lamp, and a high-pressure mercury lamp 21 was used to illuminate the lamp with a wavelength of 200 nm to 450 nm and an energy amount of 1000 mJ / m. 2 The mixture was cured by ultraviolet irradiation at 1000 K to form the concave-convex sheet member 1. Thereafter, the concave-convex sheet member 1 cured in the mold was peeled off from the mold. The obtained textured sheet member 1 was almost the same as that shown in Figure 1, with a 0.05 mm thick thin film formed by curing the mixture BL laminated on a 250 μm thick PET substrate, and long rectangular parallelepiped convex portions 4 with a width of 6 mm, a height of 5 mm, and a pitch of 20 mm arranged in one direction on the film.

[0089] This uneven sheet member 1 is made of ultrafine acrylic fiber XAI (registered trademark) (basis weight 1000 g / m 2A sound-insulating structure was produced by attaching each side of the textured sheet member 1 to a surface 8a of a flexible member 8 (25 mm thick) using double-sided tape, and attaching each side of the opposite surface 8b of the flexible member 8 to the surface of an adherend 9 made of a 0.6 mm thick steel plate. As shown in FIG. 9 , a sound-insulating structure 7 was produced in which the textured sheet member 1, the flexible member 8, and the adherend 9 were stacked in this order as viewed from a sound source 10. As shown in FIG. 10 , a sound-insulating structure 11 was produced in which the adherend 9, the flexible member 8, and the textured sheet member 1 were stacked in this order as viewed from a sound source 10.

[0090] Example 2 Sound insulating structures 7 and 11 were produced in the same manner as in Example 1, except that the concave-convex pitch of the concave-convex sheet member 1 was changed to 30 mm.

[0091] Example 3 Sound insulating structures 7 and 11 were produced in the same manner as in Example 1, except that the flexible member 8 was changed to a urethane foam having a thickness of 10 mm.

[0092] Example 4 Sound insulating structures 7 and 11 were produced in the same manner as in Example 1, except that the flexible member 8 was changed to crystalline alumina fiber MAFTEC (registered trademark) having a thickness of 12.5 mm.

[0093] Example 5 Sound insulating structures 7 and 11 were produced in the same manner as in Example 1, except that the flexible member 8 was changed to polystyrene foam having a thickness of 20 mm.

[0094] Example 6 Sound-insulating structures 7 and 11 were produced in the same manner as in Example 1, except that the side of the uneven sheet member 1 on which the uneven structure 3 is located was changed to the side of the flexible member 8, so that the configuration shown in Figure 9 became the configuration shown in Figure 14.

[0095] Example 7 Sound-insulating structures 7 and 11 were produced in the same manner as in Example 1, except that the thickness of the PET substrate of the uneven sheet member 1 was changed from 250 μm to 125 μm, and the uneven structure 3 was changed from a linear uneven structure with a width of 6 mm, a height of 5 mm, and a pitch of 20 mm to a dot-shaped uneven structure shown in Figure 6, consisting of cylindrical convex portions with a diameter of 6 mm, a height of 5 mm, and a uneven pitch of 18 mm.

[0096] Comparative Example 1 Sound insulating structures 7 and 11 were fabricated in the same manner as in Example 1, except that the flexible member 8 was changed to an acrylic plate having a thickness of 4 mm.

[0097] [Sound transmission loss measurement] Sound transmission loss was measured using the sound insulation structures produced in Examples 1 to 6 and Comparative Examples 1 to 4. The measured value when the textured sheet 1 of each sound insulation structure was replaced with a flat sheet of the same mass without texture was used as a reference, and the difference between the measured values ​​is summarized in Tables 1-1 and 1-2 below. In Tables 1-1 and 1-2, the "peak value (dB) of the difference in transmission loss from when a flat sheet of the same mass is used" when the member on the sound wave incident side is a textured sheet represents "TL1 - TL2" in the above formulas (A) to (C), and the "peak value (dB) of the difference in transmission loss from when a flat sheet of the same mass is used" when the member on the sound wave incident side is an adherend represents "TL3 - TL4" in the above formulas (A) to (C). The conditions for measuring sound transmission loss are as follows: When white noise was generated in one of two spaces separated by the sound-insulating structures produced in Examples 1 to 6 and Comparative Examples 1 to 4, the sound transmission loss (TL) was calculated based on the following formula (1) from the difference in sound pressure level at a specified location in the space where the sound was generated (sound source room) and the sound pressure level at a specified location in the other space (sound receiving room) at each center frequency in the 1 / 12 octave band from 72.8 Hz to 10,900 Hz.

[0098]

number

[0099] [Compression test] Compression tests were conducted to measure the hardness of various flexible materials using a compression testing machine, Texture Analyzer CT3-4500 (Brookfield). A load was applied perpendicular to the thickness direction of the flexible material at a speed of 0.1 mm / s using an acrylic cylindrical probe with a diameter of 12.7 mm and a height of 35 mm, and the deformation rate and load were measured. The surface of the flexible material to which the load was applied was larger than the area of ​​the bottom surface of the cylindrical probe and was flat. Table 2 shows the load (kPa) applied to various flexible members when the deformation rate is 4%.

[0100] Furthermore, "flexible member" in Tables 1-1 and 1-2 refers to a flexible member or an object that exists in the same position as a flexible member (that is, an acrylic plate in Comparative Example 1).

[0101] [Table 1-1]

[0102] [Table 1-2]

[0103] [Table 2]

[0104] As shown in Table 1 above, in Examples 1 to 7, the sound waves entered from the concave-convex sheet side. It can be seen that a sound-insulating structure laminated so that sound waves are incident from the adherend side has higher sound-insulating performance in the sound-insulating frequency band of the uneven sheet, compared to a sound-insulating structure laminated so that sound waves are incident from the adherend side. Furthermore, as shown in Table 2 above, in Comparative Example 1, compared to Examples 1 to 7, a highly rigid member that is less likely to deform is used as the flexible member, and the vibration of the sheet portion of the uneven sheet is inhibited, resulting in a significant decrease in sound-insulating performance near the sound-insulating frequency band of the uneven sheet, regardless of the stacking order. From the above, it was confirmed that a sound-insulating structure that uses a member with low rigidity that can follow the vibration of the sheet portion of the uneven sheet as the flexible member and is laminated so that incident sound passes through the uneven sheet, flexible member, and adherend in that order, exhibits improved sound-insulating performance in the sound-insulating frequency band of the uneven sheet.

[0105] [Reference example] [simulation] A unit cell portion having a shape substantially similar to that shown in FIG. 1 or 6, in which a concave-convex structure was imparted to the sheet portion 2, was reproduced on the simulation software COMSOL Multiphysics (registered trademark), and an infinite plane model was constructed to which periodic boundary conditions were applied. The physical properties of the sheet portion and the convex portions were as shown in Models 1 to 41 in Table 3 below. In addition, a thin film of photocurable resin with a thickness of 0.05 mm was present on the surface of the sheet portion on which the convex portions were arranged, and the convex portions made of photocurable resin were arranged on top of that, and the density of the photocurable resin was 1050 kg / m 2 The Poisson's ratio was 0.49, and the loss factor was 0.1. The elastic modulus of the photocurable resin was calculated using the following formula (3).

number

[0106] Sound transmission loss simulations were conducted for each of the sound insulation structures with shape models 1 to 41 in Table 3 below. The simulated sound transmission loss values ​​for each shape of the textured sheet were compared with the mass law value when the textured sheet was replaced with a flat sheet with no texture and whose mass and area were the same as the area of ​​the sheet portion. In this case, the weight ratio of the convex portion weight to the sheet portion weight was plotted on the horizontal axis, and the peak value of the difference was calculated by subtracting the mass law value from the sound transmission loss value when the textured sheet was used, and this value was plotted on the vertical axis in Figure 15. These results show that an excellent sound insulation effect can be obtained by setting the weight ratio of the protrusion weight to the sheet weight at 0.7 or more, preferably 2.0 or more. The relationship between the peak value of the difference and the weight ratio of the protrusion weight to the sheet weight also shows a similar tendency when the flexible member described in the embodiment section is provided.

[0107] [Table 3] [Explanation of symbols]

[0108] 1 Textured sheet material 2 Seat section 2a, 2b Seat surface 3 Uneven structure 4. Concave and convex unit shape 5, 51 Convex part 5a base 5b Weight 6 recess 7, 11 Sound insulation structure 8 Flexible Members 8a, 8b Surface of the soft member 9 Adherent 10 Sound Source 16, 17 Mold 16a, 17a cavities 18, 19 Crimping roll 20 nozzles 21 Light source 22 Rib-like protrusion 23 Rib-like protrusion

Claims

1. a concave-convex sheet member having a concave-convex structure including a sheet portion and a plurality of convex portions provided on a surface of the sheet portion; a flexible member provided on the concave-convex sheet member, the flexible member is provided on at least one surface of the concave-convex sheet member, either on a surface on which convex portions are provided or on a surface opposite to the surface on which convex portions are provided, and in a compression test using a compression tester, a load giving a deformation rate of 4% is 160 kPa or less; The sound-insulating sheet of the concave-convex sheet member has a weight ratio of the convex portions to the sheet portion, expressed as (weight of the convex portions / weight of the sheet portion), of 0.7 or more.

2. the concave-convex structure has a sheet portion and convex portions provided on a surface of the sheet portion, 2. The sound-insulating sheet according to claim 1, wherein a weight ratio of the convex portions to the sheet portion, expressed as (weight of the convex portions / weight of the sheet portion), is 0.7 or more.

3. The sound-insulating sheet according to claim 2 , further comprising an adhesive layer between the concave-convex sheet member and the soft member.

4. The surface density of the sheet portion is 2.5 kg / m ２ The sound-insulating sheet according to claim 2 or 3, wherein:

5. The density of the protrusions is 100 kg / m ３ The sound-insulating sheet according to any one of claims 2 to 4.

6. The sound-insulating sheet according to any one of claims 2 to 5, wherein the height of the convex portions is 0.1 mm or more.

7. The number ratio of the convex portions is 1,000 to 10,000 / m ２ The sound-insulating sheet according to any one of claims 2 to 6,

8. The sound-insulating sheet according to any one of claims 2 to 7, wherein a load giving a deformation rate of 4% in a compression test using the compression tester is 0.15 kPa or more.

9. The weight ratio of the convex portions to the sheet portion of the concave-convex sheet member, expressed as (weight of the convex portions / weight of the sheet portion), is 5 or less, and The sound-insulating sheet according to any one of claims 2 to 8, wherein the soft member has a load of 10 kPa or less that gives a deformation rate of 4% in a compression test using a compression tester.

10. The sound-insulating sheet according to any one of claims 2 to 9, wherein the uneven structure of the uneven sheet member is provided on the side where the soft member is present or on the opposite side thereof.

11. The sound-insulating sheet according to any one of claims 2 to 10, which is used together with a sound source and is placed with the concave-convex sheet member side facing the sound source.

12. A sound-insulating sheet according to any one of claims 2 to 11, wherein the uneven sheet member comprises a sheet portion and a convex portion protruding linearly from the sheet portion, and uneven unit shapes having the convex portion and a concave portion along the convex portion are repeatedly arranged in one or two directions on the sheet portion.

13. The sound-insulating sheet according to any one of claims 1 to 12, wherein the soft member is a nonwoven fabric.

14. The sound-proof sheet according to any one of claims 1 to 12, wherein the soft member is a foam.

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