Laminate and soundproof material

Abstract

To provide a laminate which is light in weight and excellent in rigidity, and a soundproof material using the laminate.SOLUTION: A laminate 100 includes honeycomb cores 10 and 12 composed of a plurality of columnar hollow cells partitioned by a partition wall, and a fiber layer 20. The honeycomb cores 10 and 12 are composed of a material containing polypropylene, and the fiber layer 20 contains a sheet-like fiber accumulation body formed by accumulating polypropylene fibers containing polypropylene nanofibers having fiber diameters of 1 μm or less. A soundproof material includes the laminate 100.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a laminate and a soundproof material.

Background Art

[0002] As one of the soundproofing measures for reducing noise and the like, sound-absorbing materials and the like are used. As general sound-absorbing materials, glass wool, rock wool, urethane foam, and the like are known. In addition, various sound-absorbing materials using non-woven fabrics have been proposed.

[0003] For example, Patent Document 1 discloses a laminated non-woven fabric having a surface layer portion and a base portion, wherein the surface layer portion is composed of a non-woven fabric layer ((1) layer) made of nanofibers of a thermoplastic resin having a number-average single fiber diameter of 1 to 500 nm, and a non-woven fabric layer ((2) layer) made of fibers having a number-average single fiber diameter larger than that of the nanofibers, and having a basis weight of 30 to 100 g / m 2 is non-woven fabric A, and the base portion is a non-woven fabric B having a basis weight of 200 to 800 g / m 2 and containing 10% by mass or more of fibers having a single fiber diameter of 15 μm or less, and a laminated non-woven fabric having a sound absorption rate of 85% or more at 2000 Hz is disclosed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the sound-absorbing material such as that in Patent Document 1 does not have sufficient rigidity, and a more easily handleable soundproof material has been demanded. Under such circumstances, an object of the present invention is to provide a lightweight laminate excellent in rigidity and soundproofing properties, and a soundproof material using the laminate.

Means for Solving the Problems

[0006] As a result of intensive studies to solve the above problems, the present inventor has found that the following invention meets the above object, and has reached the present invention. That is, the present invention relates to the following invention.

[0007] The laminate of the present invention is a laminate including a honeycomb core composed of a plurality of columnar hollow cells partitioned by partition walls, and a fiber layer disposed on at least one of the main surfaces of the honeycomb core, wherein the honeycomb core is made of a material containing polypropylene, and includes a sheet-like fiber integrated body in which polypropylene fibers containing polypropylene nanofibers with a fiber diameter of 1 μm or less are integrated.

[0008] By adopting a configuration in which a honeycomb core made of a material containing polypropylene and a fiber layer containing polypropylene fibers are laminated, a structure with light weight and imparted rigidity and toughness can be obtained. In addition, excellent mechanical properties, flexural fatigue resistance, heat resistance, electrical properties, and chemical resistance can be achieved.

[0009] In addition, the fiber integrated body constituting at least a part of the fiber layer of the laminate of the present invention is a porous structure body having non-uniform pore diameters and variations. By combining such a porous structure body and a honeycomb core, it is considered that the sound absorption property is improved.

[0010] In the laminate of the present invention, it is preferable that the fiber layer has a plurality of through holes penetrating in the thickness direction. By further providing through holes in a porous structure body having variations in pore diameter, it is considered to contribute to the improvement of the sound absorption property.

[0011] In the laminate of the present invention, it is preferable that the fiber layer has the fiber integrated body and a pair of non-woven fabric sheets sandwiching the fiber integrated body. With such a configuration, handling becomes easier, and the durability of the fiber layer can be further improved.

[0012] The laminate of the present invention can be configured such that the honeycomb core is disposed on both sides of the main surface of the fiber layer. By adopting such a configuration, the sound absorption performance can be improved.

[0013] The laminate of the present invention can be configured such that the fiber layer is disposed on both sides of the main surface of the honeycomb core. By adopting such a configuration, the sound absorption performance can be improved.

[0014] The laminate of the present invention can be configured to include the honeycomb core, the fiber layer disposed on one of the main surfaces of the honeycomb core, and a resin layer made of polypropylene resin disposed on the side opposite to the side where the fiber layer of the honeycomb core is disposed. By adopting such a configuration, the sound insulation performance can be improved, and the laminate is also easy to install.

[0015] The laminate of the present invention can be configured to include the fiber layer, the honeycomb core disposed on one of the main surfaces of the fiber layer, and a resin layer made of polypropylene resin disposed on the side opposite to the side where the honeycomb core of the fiber layer is disposed. By adopting such a configuration, the sound insulation performance can be improved, and the laminate is also easy to install.

[0016] In the laminate of the present invention, the minimum fiber diameter of the polypropylene nanofibers is 500 nm or less, the basis weight of the fiber assembly is 90 g / m 2 ~700 g / m 2 and preferably the thickness of the fiber assembly is 1 mm to 10 mm. By adopting such a configuration, the sound absorption performance can be improved.

[0017] The sound insulation material of the present invention includes the laminate of the present invention. Since the laminate of the present invention is lightweight and excellent in rigidity and sound insulation performance, it can be suitably used as a sound insulation material.

Effects of the Invention

[0018] According to the present invention, there are provided a laminate that is lightweight and excellent in rigidity and sound insulation, and a sound insulation material using the laminate.

Brief Description of the Drawings

[0019]

Figure 1

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Figure 11

Embodiments for Carrying Out the Invention

[0020] Hereinafter, with reference to FIGS. 1 to 11, the laminate of the present invention will be described in detail. In FIGS. 1 to 11, the same reference numerals are given to the common parts and the description thereof is omitted. In addition, when the expression "~" is used in this specification, it is used as an expression including the numerical values or physical property values before and after it.

[0021] <Embodiment 1> Based on FIGS. 1 to 5, the laminate 100 according to the embodiment of the present invention will be described. FIG. 1 is a diagram for explaining the outline of the laminate 100, FIG. 2 is a cross-sectional view of the laminate 100, FIG. 3 is an enlarged plan view showing a part of the laminate 100, FIG. 4 is an enlarged cross-sectional view showing a part of the fiber layer 20 constituting the laminate 100, and FIG. 5 is an enlarged plan view showing a part of the fiber layer 20.

[0022] As shown in FIGS. 1 and 2, the laminate 100 includes a honeycomb core 10, a fiber layer 20, and a honeycomb core 12. The honeycomb core 10 and the honeycomb core 12 are laminated via the fiber layer 20, and the laminate 100 is a panel in which honeycomb cores (honeycomb core 10, honeycomb core 12) are arranged on both sides of the main surface (a surface perpendicular to the thickness direction) of the fiber layer 20. The thickness Tt of the laminate 100 is about 20 mm to 100 mm, and is appropriately set according to the purpose, such as 25 mm to 80 mm or 30 mm to 60 mm.

[0023] (Honeycomb Core) As shown in FIG. 3, the honeycomb core 10 is a cell assembly composed of a plurality of columnar hollow cells 10S partitioned by partition walls 10W. Each hollow cell 10S has a hexagonal shape in plan view. The plurality of hollow cells 10S share adjacent hollow cells 10S and partition walls 10W (one side of the hexagon in plan view) and are arranged in a single row on the plane. Both ends of each hollow cell 10S in the thickness direction are open, and the upper and lower surfaces of the honeycomb core 10 have a plurality of openings.

[0024] The size of the hollow cell 10S is not particularly limited. For example, the outer diameter d (diameter of the circumscribed circle) can be 3 mm to 15 mm, or 5 mm to 10 mm. Also, the thickness t of the partition wall 10W cIt can be, for example, 0.2 mm to 1.5 mm, or 0.3 mm to 1.0 mm, etc.

[0025] The honeycomb core 10 is made of a material containing polypropylene and is not limited to pure polypropylene. It may be composed of a mixture of polypropylene and a modified polyolefin, or contain components other than polypropylene. From the perspective of adhesion to the fiber layer 20, it is preferably composed of a material containing 50% by mass or more of polypropylene, more preferably 55% by mass or more. Further, in order to impart anti-inflammatory properties, the honeycomb core is preferably made of anti-inflammatory polypropylene and may contain a flame retardant or a non-combustible agent.

[0026] The thickness T of the honeycomb core 10 1 is not particularly limited and can be appropriately adjusted according to the application and the like. The thickness T of the honeycomb core 10 1 is preferably 5 mm to 50 mm, more preferably 8 mm to 35 mm, even more preferably 10 mm to 25 mm, and still more preferably 12 mm to 20 mm.

[0027] Note that the shape of the hollow cells 10S in plan view is not limited to hexagonal, and may be circular, elliptical, or the like. Also, the manufacturing method of the honeycomb core can be selected according to the shape of the hollow cells 10S and is not particularly limited. The honeycomb core can be obtained by a known method using an appropriate adhesive as needed.

[0028] (Honeycomb core) The honeycomb core 12 is disposed on the side opposite to the side where the honeycomb core 10 of the fiber layer 20 is disposed (see Fig. 2). The honeycomb core 12, like the honeycomb core 10, is composed of a plurality of columnar hollow cells partitioned by partitions and is made of a material containing propylene. In the laminate 100, the honeycomb core 12 is the same as the honeycomb core 10.

[0029] (Fiber layer) The fiber layer 20 is a layer that covers one of the main surfaces (the surface perpendicular to the thickness direction) of the honeycomb core 10. As shown in FIGS. 4 and 5, the fiber layer 20 has a fiber aggregate 22 and a pair of nonwoven sheets 24 and 26 that sandwich the fiber aggregate 22, and a plurality of through holes 20H penetrating in the thickness direction are formed.

[0030] The fiber aggregate 22 is a sheet-like porous structure in which polypropylene fibers are aggregated and the polypropylene fibers are irregularly intertwined. The polypropylene fibers include at least polypropylene nanofibers with a fiber diameter of 1 μm or less. The minimum fiber diameter of this nanofiber is preferably 800 nm or less, and more preferably 500 nm or less.

[0031] Further, the fiber aggregate 22 may include a plurality of polypropylene fibers having different fiber diameters. The polypropylene fibers preferably include fibers with a fiber diameter exceeding 1 μm in addition to the polypropylene nanofibers. Specifically, the fiber aggregate 22 has a structure in which polypropylene nanofibers with a fiber diameter of 100 nm or more and 1 μm or less are intertwined with polypropylene fibers with a fiber diameter exceeding 1 μm and 20 μm or less, or a structure in which polypropylene nanofibers with a fiber diameter of 200 nm or more and 1 μm or less are intertwined with polypropylene fibers with a fiber diameter exceeding 1 μm and 10 μm, or a structure in which polypropylene nanofibers with a fiber diameter of 300 nm or more and 1 μm or less are intertwined with polypropylene fibers with a fiber diameter exceeding 1 μm and 5 μm or less, etc. Thus, by including fibers with different fiber diameters, the pore diameters are not uniform, and the pore diameters are non-uniform and vary, which is considered to contribute to the improvement of sound insulation performance.

[0032] The thickness t of the fiber aggregate 22 1 is preferably 1 mm to 10 mm, and more preferably 2.5 mm to 7.5 mm.

[0033] The basis weight of the fiber aggregate 22 is 2 ~700 g / m 2 is preferably, 2 ~700 g / m 2 more preferably, 2 300 g / m2 is more preferable.

[0034] The density of the fibers in the fiber assembly 22 is 0.01 g / cm 3 ~0.15 g / cm 3 is preferable, and 0.03 g / cm 3 ~0.12 g / cm 3 is more preferable, and 0.05 g / cm 3 ~0.10 g / cm 3 is even more preferable.

[0035] The method for manufacturing the fiber assembly 22 is not particularly limited, and for example, it can be obtained by using the meltblowing method, the spunbond method, or the like. Since it is easy to obtain a fiber assembly containing polypropylene nanofibers and having an appropriate distribution in the fiber diameter, the fiber assembly 22 is preferably an assembly of meltblown fibers. That is, it is preferably an assembly obtained by integrating polypropylene by the meltblowing method.

[0036] As shown in FIGS. 4 and 5, on both sides of the fiber assembly 22, a pair of nonwoven fabric sheets 24 and 26 that sandwich the fiber assembly 22 are arranged. The nonwoven fabric sheet 24 and the nonwoven fabric sheet 26 are nonwoven fabric sheets composed of polypropylene fibers.

[0037] The nonwoven fabric sheets 24 and 26 are thinner than the fiber assembly 22, and the thickness t 2 is preferably 0.01 mm to 1 mm or less, more preferably 0.02 mm to 0.50 mm, even more preferably 0.03 mm to 0.25 mm, and even more preferably 0.05 mm to 0.15 mm.

[0038] The basis weight of the nonwoven fabric sheets 24 and 26 is smaller than that of the fiber assembly 22, and 0.5 g / m 2 ~80 g / m 2 is preferable, 1 g / m 2 ~50 g / m 2 is more preferable, and 5 g / m 2 ~30 g / m 2 is even more preferable.

[0039] The density of the nonwoven sheets 24 and 26 is greater than that of the fiber assembly 22, and is preferably 0.05 g / cm 3 ~0.60 g / cm 3 Preferably, it is 0.10 g / cm 3 ~0.50 g / cm 3 More preferably, it is 0.12 g / m 3 ~0.40 g / cm 3 Even more preferably.

[0040] The nonwoven sheet is preferably heat-bonded. By arranging the heat-bonded sheets on both sides of the fiber assembly 22, the durability is improved.

[0041] The opening area per through-hole 20H is 0.7 mm 2 ~25 mm 2 or 3 mm 2 ~20 mm 2 5 to 15 mm 2 The through-holes 20H are preferably provided at intervals of about 1 cm to 10 cm or 2 cm to 5 cm. Also, in FIG. 5, the shape of the through-holes 20H in plan view is circular, but it is not limited thereto, and it may be polygonal.

[0042] The fiber layer 20 can be obtained, for example, by sandwiching the fiber assembly 22 with nonwoven sheets 24 and 26 and sewing (quilting), or by bonding them together using an adhesive, an adhesive film, etc., and then providing through-holes 20H at predetermined intervals using a needle or the like. The nonwoven sheets 24 and 26 may have the same configuration or different configurations. Further, the fiber layer 20, the honeycomb core 10, and the honeycomb core 12 can be joined together using a joining member such as an adhesive, a bolt, or a screw so as not to impair the air permeability, thereby obtaining the laminate 100.

[0043] In the laminate 100, the honeycomb core 10 and the honeycomb core 12 may have different configurations, but a preferred embodiment of the honeycomb core 12 is the same as that of the honeycomb core 10. For example, the size and thickness of the hollow cells of the honeycomb core 12 may be different from those of the honeycomb core 10, but are preferably within the above-described ranges of the size and thickness.

[0044] When the sound insulation performance was evaluated using this laminate 100, the sound pressure level transmitted through the laminate 100 could be set to 40 dB or less.

[0045] <Embodiment 2> FIG. 6 is a cross-sectional view of a laminate 101 according to another embodiment of the present invention. The laminate 101 includes a resin layer 30, a honeycomb core 10, a fiber layer 20, and a honeycomb core 12. The laminate 101 is the same as the laminate 100 except for having the resin layer 30, and the thickness T of the laminate 101 t is about 20 mm to 100 mm.

[0046] (Resin layer 30) The resin layer 30 is a layer disposed on the side opposite to the side where the fiber layer 20 of the honeycomb core 10 is disposed, and is composed of a polypropylene resin sheet (PP sheet) obtained by melt molding a polypropylene resin or the like. By having the resin layer 30 on the outermost surface, it becomes easy to attach to an attachment target such as a wall, and the resin layer 30 can function as a sound insulation wall. The thickness T of the resin layer 30 3 is appropriately designed according to the thicknesses of the honeycomb cores 10 and 12 and the fiber layer 20, etc., but is, for example, about 0.5 mm to 2 mm, or about 0.6 mm to 1.5 mm. There is no particular limitation on the method of joining the resin layer 30 and the honeycomb core 10, and the resin layer 30 and the honeycomb core 10 can be adhered using an adhesive or an adhesive film.

[0047] <Embodiment 3> FIG. 7 is a cross-sectional view of a laminate 102 according to another embodiment of the present invention. The laminate 102 includes a fiber layer 20, a honeycomb core 10A, and a fiber layer 20A, and the fiber layers (fiber layer 20, fiber layer 20A) are disposed on both sides of the main surface of the honeycomb core 10A. The laminate 102 has a structure in which the honeycomb core 10A is sandwiched between the fiber layer 20 and the fiber layer 20A, and its thickness T t is 20 mm to 100 mm, 25 mm to 80 mm, or 30 mm to 60 mm.

[0048] The honeycomb core 10A has the same configuration as the honeycomb core 10, but the thickness T 1a of the honeycomb core 10A is preferably 15 mm to 90 mm, more preferably 20 mm to 80 mm, still more preferably 22 mm to 70 mm, and even more preferably 25 mm to 60 mm.

[0049] The fiber layer 20A is disposed on the side opposite to the side where the fiber layer 20 of the honeycomb core 10A is disposed. The fiber layer 20A has a sheet-like fiber aggregate in which polypropylene fibers containing polypropylene nanofibers with a fiber diameter of 1 μm or less are integrated between a pair of nonwoven fabric sheets, and has a plurality of through holes 20H penetrating in the thickness direction. The fiber layer 20A may have the same configuration as or a different configuration from the fiber layer 20, but a preferred embodiment of the fiber layer 20A is the same as that of the fiber layer 20.

[0050] <Embodiment 4> FIG. 8 is a cross-sectional view of a laminate 103 according to another embodiment of the present invention. The laminate 103 includes a resin layer 30A, a fiber layer 20, a honeycomb core 10A, and a fiber layer 20A. The laminate 103 is the same as the laminate 102 except that it has a resin layer 30A, and the thickness T t of the laminate 103 is about 20 mm to 100 mm.

[0051] (Resin layer 30A) The resin layer 30A is a layer disposed on the side opposite to the side where the honeycomb core 10A of the fiber layer 20 is disposed, and is composed of a polypropylene resin sheet (PP sheet) obtained by melt molding a polypropylene resin or the like. By having the resin layer 30A as the outermost layer, it becomes easier to attach to an attachment target such as a wall, and the resin layer 30A can function as a sound insulation wall. The thickness T of the resin layer 30A 3a is appropriately designed according to the thickness of the honeycomb core 10A, the fiber layer 20, the fiber layer 20A, etc. For example, it is about 0.5 mm to 2 mm, or about 0.6 mm to 1.5 mm. There is no particular limitation on the bonding method between the resin layer 30A and the fiber layer 20A, and the resin layer 30 and the fiber layer 20A can be bonded using an adhesive, an adhesive film, or the like.

[0052] <Embodiment 5> FIG. 9 is a cross-sectional view of a laminate 104 according to another embodiment of the present invention. The laminate 104 is a laminate in which a fiber layer 20 and a honeycomb core 10A are laminated.

[0053] <Embodiment 6> FIG. 10 is a cross-sectional view of a laminate 105 according to another embodiment of the present invention. The laminate 105 is a three-layer laminate in which a resin layer 30A, a fiber layer 20, and a honeycomb core 10A are laminated in this order.

[0054] <Embodiment 7> FIG. 11 is a cross-sectional view of a laminate 106 according to another embodiment of the present invention. The laminate 106 shown in FIG. 9 is a three-layer laminate in which a fiber layer 20, a honeycomb core 10A, and a resin layer 30 are laminated in this order.

[0055] As described above, the laminate according to the present invention has been described. However, the laminates described with reference to FIGS. 1 to 11 are examples of the laminate according to the present invention, and are not limited thereto. For example, the fiber layer constituting the laminate according to the present invention is not limited to a configuration in which a fiber aggregate is sandwiched between a pair of non-woven fabric sheets, and the fiber aggregate may be joined to the honeycomb core. Further, the honeycomb core and the fiber layer may be alternately laminated in four or more layers.

[0056] <Sound insulation material> In the fiber layer of the laminate of the present invention, the wavelength of the incident wave (sound) can be decomposed or diffusely reflected to convert sound energy into thermal energy. The finely decomposed wavelength energy is diffracted and absorbed by the honeycomb core composed of porous cells and disappears, or forms a new vibrator with another weak wavelength. When having a resin layer, this becomes a sound insulation wall, and the transmission air can be vibrated on the sound insulation wall to produce a new bass sound. Therefore, the laminate of the present invention is preferably used as a member of a sound insulation material. Depending on the purpose, the number of laminations of the honeycomb core and the fiber layer, etc. can be appropriately designed. When the laminate of the present invention has a resin layer, it is preferably attached so that the resin layer side is in contact with the attachment target. Further, although the laminate according to the present invention described with reference to FIGS. 1 to 11 is rectangular in plan view, it is not limited thereto, and it can have an arbitrary shape according to the attachment target such as a wall, a ceiling, or the inner surface of a device. The sound insulation material provided with the laminate of the present invention is lightweight and rigid, so it is easy to attach and has excellent sound insulation performance.

Industrial applicability

[0057] The laminate of the present invention can be used as a member of a sound insulation material and is industrially useful.

Explanation of symbols

[0058] 10, 10A, 12 Honeycomb core 10S Hollow cell 10W Partition wall 20, 20A Fiber layer 20H Through hole 22 Fiber aggregate 24, 26 Nonwoven fabric sheet 30, 30A Resin layer 100, 101, 102, 103, 104, 105, 106 Laminate

Claims

1. A laminate comprising a honeycomb core composed of a plurality of columnar hollow cells partitioned by partitions, and a fiber layer disposed on at least one of the main surfaces of the honeycomb core, wherein the honeycomb core is composed of a material containing polypropylene, the fiber layer includes a sheet-like fiber aggregate in which polypropylene fibers containing polypropylene nanofibers having a fiber diameter of 1 μm or less are integrated.

2. The laminate according to claim 1, wherein the fiber layer has a plurality of through holes penetrating in the thickness direction.

3. The laminate according to claim 1, wherein the fiber layer has the fiber aggregate and a pair of non-woven fabric sheets sandwiching the fiber aggregate.

4. The laminate according to claim 1, wherein the honeycomb core is disposed on both sides of the main surface of the fiber layer.

5. The laminate according to claim 1, wherein the fiber layer is disposed on both sides of the main surface of the honeycomb core.

6. the honeycomb core, the fiber layer disposed on one of the main surfaces of the honeycomb core, and a resin layer composed of a polypropylene resin disposed on the side opposite to the side where the fiber layer of the honeycomb core is disposed.

7. the fiber layer, the honeycomb core disposed on one of the main surfaces of the fiber layer, and a resin layer composed of a polypropylene resin disposed on the side opposite to the side where the honeycomb core of the fiber layer is disposed.

8. The minimum fiber diameter of the polypropylene nanofibers is 500 nm or less. The basis weight of the fiber assembly is 90 g / m 2 to 700 g / m 2 and the thickness of the fiber assembly is 1 mm to 10 mm. The laminate according to claim 1.

9. A soundproof material comprising the laminate according to any one of claims 1 to 8.

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