JP2020013001A - Heat insulating sound absorbing material, heat insulating sound absorbing laminate, and heat insulating sound absorbing material manufacturing method - Google Patents

Abstract

To provide a heat insulating sound absorbing material which has excellent sound absorbing properties and excellent heat insulating performance, and can be easily applied to a building frame such as a wall surface.SOLUTION: The heat insulating sound absorbing material is formed by compressing a resin foam and has a plurality of non-through holes on at least one surface.SELECTED DRAWING: None

Description

  The present invention relates to a heat insulating sound absorbing material, a heat insulating sound absorbing laminate, and a method for manufacturing a heat insulating sound absorbing material.

  As a sound-absorbing / sound-insulating material for buildings, fiber-based aggregates such as glass wool, which are inexpensive, have excellent lightweight properties, and also have heat insulating performance, are widely used. Since sound absorption performance of fiber-based aggregates such as glass wool deteriorates due to water absorption due to dew condensation or rainwater intrusion, Patent Literature 1 discloses applying a skin material covering the fiber-based aggregates.

JP-A-11-202872

  However, the sound-absorbing material of Patent Document 1 has insufficient strength. Therefore, when the sound-absorbing material is applied to a wall surface of a concrete body or the like, a panel is used to cover the surface material, or a pier or the like is applied and filled in the meantime. I have no choice.

  Therefore, an object of the present invention is to provide a heat insulating and sound absorbing material which is excellent in sound absorbing properties and heat insulating performance and can be easily applied to a frame such as a wall surface.

  The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, completed the present invention.

  That is, the heat insulating sound absorbing material of the present invention is obtained by compressing a resin foam and has a plurality of non-through holes on at least one surface.

  The heat-insulating sound-absorbing material of the present invention "has a compression strain of 10% or more and 50% or less, and a ratio of an opening area of the non-through hole to an area of a surface having the non-through hole of 50% or less". "The maximum value of the normal incidence sound absorption coefficient of the surface having the non-through hole in the frequency range of 500 Hz or more and 6400 Hz or less is 40% or more", and "The thermal conductivity does not have the non-through hole." That the thermal conductivity of the compressed resin foam is substantially the same, "the resin foam is a styrene-based resin foam," "compressed plate-shaped resin foam, Plate-like ”as a preferred embodiment.

  Further, the heat-insulating sound-absorbing laminate of the present invention is obtained by laminating the heat-insulating sound-absorbing material of the present invention, and each of the heat-insulating sound-absorbing materials has a surface having the non-through hole in a frequency range of 500 Hz to 6400 Hz. It is characterized in that the frequency indicating the maximum value of the normal incidence sound absorption coefficient is different.

  The heat-insulating sound-absorbing laminate of the present invention includes, as a preferred embodiment, "the heat-insulating sound-absorbing material is laminated with the surface having the non-through hole facing in the same direction".

  Further, the method for producing a heat insulating sound absorbing material of the present invention includes, in this order, a step of compressing a resin foam and a step of forming a plurality of non-through holes on at least one surface of the resin foam. Features.

  INDUSTRIAL APPLICABILITY The heat insulating and sound absorbing material of the present invention has excellent sound absorbing properties and heat insulating performance, and can be easily applied to a frame such as a wall surface, and can be suitably used, for example, as a heat insulating and sound absorbing material for buildings.

≪Insulated sound absorbing material≫
The heat insulating sound absorbing material of the present invention is obtained by compressing a resin foam and has a plurality of non-through holes on at least one surface.

<Resin foam>
The resin foam used in the present invention is not particularly limited, but a styrene resin foam obtained by foaming a styrene resin is preferable. Further, the resin foam is preferably plate-shaped. Hereinafter, a styrene resin foam will be described in detail by way of example.

[Styrene resin]
The styrene-based resin is not particularly limited, and may be obtained from a styrene-based monomer such as a polystyrene homopolymer obtained from only a styrene monomer, methylstyrene, ethylstyrene, isopropylstyrene, dimethylstyrene, and chlorostyrene. Homopolymers, random, block or graft copolymers obtained from styrene monomers and monomers copolymerizable with styrene or derivatives thereof, modified polystyrene such as brominated polystyrene, rubber-reinforced polystyrene, etc. Is mentioned.

  Examples of monomers copolymerizable with styrene include styrene derivatives such as methylstyrene, dimethylstyrene, ethylstyrene, diethylstyrene, isopropylstyrene, bromostyrene, dibromostyrene, tribromostyrene, chlorostyrene, dichlorostyrene, and trichlorostyrene; Vinyl compounds such as vinyltoluene, vinylxylene, divinylbenzene, etc., unsaturated compounds such as acrylic acid, methacrylic acid, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butadiene, acrylonitrile or derivatives thereof, and maleic anhydride And itaconic anhydride. These can be used alone or in combination of two or more. In the present invention, among the above-mentioned styrene-based resins, a polystyrene homopolymer can be particularly preferably used from the viewpoint of economic efficiency and moldability.

  The weight average molecular weight of the styrene resin is 100,000 to 350,000, preferably 150,000 to 300,000, and more preferably 180,000 to 250,000.

[Blowing agent]
The blowing agent used in the present invention includes a physical blowing agent and a thermal decomposition type chemical blowing agent. Examples of the physical foaming agent include, but are not particularly limited to, carbon dioxide, nitrogen, argon, helium, air, water, and other inorganic gases, methane, ethane, propane, butane (normal butane, isobutane), and pentane (normal pentane, isopentane, neopentane). , Cyclopentane) and hexane; aliphatic alcohols such as methanol, ethanol and propanol; ethers such as dimethyl ether; alkyl chloride hydrocarbons such as methyl chloride and ethyl chloride. In addition to this, a CFC-based foaming agent can be used, but since there is a possibility that the ozone layer is destroyed and global warming is caused, it is preferable to refrain from using as much as possible in consideration of the environment. As an alternative, a hydrofluoroolefin and a hydrochlorofluoroolefin-based blowing agent having an ozone depletion potential of 0 and a low global warming potential can be used.

  The amount of the foaming agent added to the styrene-based resin is 3 to 30 parts by mass, preferably 5 to 15 parts by mass, more preferably 5 to 10 parts by mass based on 100 parts by mass of the styrene-based resin.

[Other additives]
To impart flame retardancy, a halogen-based flame retardant may be added, and a flame retardant usually used for a thermoplastic resin can be used without any particular limitation. In addition, in order to adjust the size of the bubbles as needed, bubble regulators such as talc and calcium silicate, extrusion aids such as barium stearate and calcium stearate, and deoxidizing agents such as magnesium oxide and tetrasodium pyrophosphate It is desirable to add such. Further, graphite, carbon black, titanium dioxide or the like may be added as a radiation reducing agent.

[Production method of styrene resin foam]
The styrene-based resin foam used in the present invention is, for example, an extrusion-foamed styrene-based resin foam, which is obtained by heating and melting a styrene-based resin, under high temperature and high pressure, and kneading the foaming agent by press-fitting the molten resin. This can be the same as a known method of manufacturing by cooling to a temperature suitable for extrusion foaming and extrusion foaming under low pressure through a die.

  In addition, the bead method styrene-based resin foam is pre-foamed by heating and expanding a small translucent material bead having a diameter of about 0.3 to 2 mm containing a foaming agent (butane, pentane) by applying steam. This foamed bead is put into a mold, and steam is applied again. This can be performed in the same manner as a known method in which expanded beads are stuck together by heat to obtain a product in the shape of the mold.

<Compression strain>
It is preferable that the heat insulating sound-absorbing material of the present invention is formed by compressing a resin foam, and by compression, wrinkles are formed on at least a part of a film of bubbles constituting the resin foam.

  The method (pressing device) for compressing the resin foam is not particularly limited, but includes a method using a press machine, and a method for passing the resin foam between rolls having an interval smaller than the plate thickness. Here, depending on hardness, compressive strength, and required compression strain, a method of compressing a plurality of times by a press machine or passing a plurality of times between rolls to obtain a predetermined compression strain is preferable.

  A foam is an aggregate of cells, and a gas (foaming agent, air, etc.) is enclosed in the cells. Therefore, when the thickness partially recovers after compression, a recovery rate is assumed in advance. It is necessary to determine the compression strain (press ratio, roll interval with respect to foam thickness). The thickness recovery rate also varies depending on the curing period after extrusion foaming. That is, the foam may be compressed immediately after being extruded and foamed from the die, or the cured foam may be compressed, but it is necessary to consider the thickness recovery rate. Here, when the foam is compressed immediately after foaming from the die, it is difficult to form wrinkles in the foam film unless the temperature of the foam falls below the glass transition point.

  The formation of wrinkles in the film of bubbles constituting the foam is due to the fact that bubbles in the surface layer of the foam (for example, in the case of a plate shape, can be largely divided into two surface layers and a central layer sandwiched therebetween) are small. The flatter the air bubbles in the surface layer, the more wrinkles are formed. Generally, in the board after extrusion foaming, the surface layer is cooled faster than the center layer, so that the bubbles in the surface layer are small and flat, and many wrinkles are formed in the bubbles in the surface layer.

  In a foam board obtained by slicing a large cross section of the foam into several pieces perpendicular to the thickness direction (that is, parallel to the length or width direction), products near the center in the thickness direction (products near the center layer) have bubbles inside the cross section. , The wrinkles are formed in the central layer when compressed. In addition, when a foamed plate that has been secondarily foamed after being extruded and foamed from a die is compressed, the density of the surface layer of the foam becomes low, so that many wrinkles are likely to be formed on the surface layer. Depending on the physical properties of the foam before compression, it is possible to change the position at which wrinkles are formed, such as the central layer, the surface layer, both surface layers, and one surface layer.

  Here, the foam board in which many wrinkles are formed in the central layer has a high surface hardness. Conversely, a foamed plate having many wrinkles formed on the surface layer has a soft surface condition and can be used properly depending on the application.

The compressive strain of the heat insulating sound-absorbing material of the present invention is not particularly limited, but is preferably 10% or more and 50% or less, more preferably 15% or more and 40% or less. Here, the compression strain is a value obtained by the following equation (1).
Compressive strain [%] = ((thickness before compression−thickness after compression) / thickness before compression) × 100 (1)

  When the compressive strain is 10% or more, the heat insulating property and the sound absorbing property are sufficiently improved, and when the compressive strain is 50% or less, warpage does not occur in the heat insulating sound absorbing material, which is preferable from the viewpoint of compressive strength. .

<Non-through hole>
The heat-insulating sound-absorbing material of the present invention has a plurality of non-through holes on at least one surface. Since the surface having the non-through holes is a sound absorbing surface, it is preferable that the surface be opposed to the sound incident direction. When the heat-insulating sound absorbing material has a plate shape, the surface having the non-through holes is preferably a surface perpendicular to the thickness direction. Of course, non-through holes may be provided on a plurality of surfaces. The opening shape of the non-through hole on the surface is not particularly limited, such as a circle, an ellipse, and a rectangle. Further, the non-through hole may have a groove shape or a slit shape, and its cross-sectional shape may be any of a substantially circular shape, a substantially elliptical shape, a substantially rectangular shape, and a substantially trapezoidal shape.

  The opening diameter and depth of the non-through hole are not particularly limited, but the ratio of the opening area of the non-through hole to the area of the surface having the non-through hole is preferably 50% or less, more preferably 40% or less, and furthermore Preferably it is 35% or less. When this ratio is 50% or less, non-through holes do not communicate with each other, and the heat insulating and sound absorbing material does not become mechanically brittle, which is preferable.

  The method of forming the non-through hole is not particularly limited, but it can be formed by pressing a processing device provided with a number of sharp members such as needles and pins at a constant pitch against the surface of the resin foam. Here, by heating the sharp member to a temperature equal to or higher than the softening point of the resin constituting the resin foam, more clear holes can be formed. In addition, a non-through hole can be formed by passing a resin foam between a rotating roll having a sharp member provided on the roll surface, for example, a needle roll and a receiving roll. Examples of the method of forming a groove-shaped or slit-shaped non-through hole include cutting with a circular saw, a trimmer, a router, and the like, pressing with a convex roll, and melting with a hot wire.

<Normal incidence sound absorption coefficient>
In the heat-insulating sound-absorbing material of the present invention, the maximum value of the normal incidence sound absorption coefficient of the surface having the non-through hole in the frequency region of 500 Hz or more and 6400 Hz or less is preferably 40% or more, more preferably 45% or more, and furthermore Preferably it is 50% or more. When the maximum value of the normal incidence sound absorption coefficient of the surface having the non-through hole in the frequency region of 500 Hz or more and 6400 Hz or less is 40% or more, particularly high-range sound can be efficiently absorbed, which is preferable. The normal incidence sound absorption coefficient can be determined based on ASTM E 1050 (ISO10534-2).

<Thermal conductivity>
The thermal conductivity of the heat insulating sound-absorbing material of the present invention is substantially the same as the thermal conductivity of the compressed resin foam having no non-through holes, preferably the compressed resin foam having no non-through holes. Is preferably within ± 1% of the thermal conductivity, more preferably ± 0.5%.

  The thermal conductivity of the heat insulating sound-absorbing material of the present invention can be measured by a measurement method specified in JIS A 1412-2: 1999 in the case of one extruded polystyrene foam heat insulating plate specified in JIS A 9521: 2017.

<Other characteristics>
The compressive strength (defined by JIS A 9511: 2006) of the heat insulating sound absorbing material of the present invention is preferably 10 N / cm ² or more. When it is less than 10 N / cm ² , there is a limit in use for heat insulation. Compressive strength is more preferably 15N / cm ² or more, further preferably 20 N / cm ² or more.

The heat insulating sound absorbing material of the present invention preferably has a moisture permeability coefficient (defined by JIS A 9511: 2006) of 145 ng / m ² · s · Pa or less. When this value is large, the amount of water vapor permeation increases, and when used as a heat insulating material for a wall or the like, there is a possibility that dew condensation may occur depending on the wall configuration.

≪Insulated sound absorbing laminate 積 層
The heat insulating sound absorbing laminate of the present invention is obtained by laminating the above heat insulating sound absorbing material of the present invention. Each of the heat-insulating sound-absorbing materials constituting the heat-insulating sound-absorbing laminate of the present invention has a different frequency indicating the maximum value of the normal incidence sound absorption coefficient of the surface having the non-through hole in the frequency range of 500 Hz to 6400 Hz. Therefore, a plurality of sounds having different frequencies can be efficiently absorbed in the frequency range of 500 Hz to 6400 Hz.

  The heat insulating sound absorbing material may be a single-sided sound absorbing type in which the surfaces having non-through holes are laminated in the same direction, or a double-sided sound absorbing type in which the surfaces having non-through holes are laminated in different directions.

  The method of laminating the heat insulating sound absorbing material is not particularly limited. For example, a method of laminating the heat insulating sound absorbing material so that the non-through holes are not blocked, such as fixing the periphery of the heat insulating sound absorbing material, is preferable.

≪Resin foam≫
The resin foam used in the examples is as follows.
Extrusion method styrene-based resin foam board (XPS): Stylo Ace (trade name), manufactured by Dow Chemical Industries, Ltd., thickness 30 mm, density 30 kg / m ³
Bead method styrene resin foam board (EPS): foam board obtained by slicing a product with a thickness of 50 mm to a thickness of 30 mm, density of 20 kg / m ³

<Density measurement>
The density of the foam was calculated by dividing the mass (kg) of the foam by the volume (m ³ ) of the foam.

<< Example 1 >>
The extruded styrene resin foam board (XPS) was compressed in the thickness direction by a press machine so that the compression strain was 10%. Next, using a pin (needle) having a diameter of 0.5 mm, five non-through holes having a hole diameter of 0.5 mm and a depth of 1 cm were formed on one surface perpendicular to the thickness direction of the foamed board at 5 holes / cm ² (area ratio: 1.0%) to obtain a heat insulating sound absorbing material. This thermal insulation material was evaluated by the following method. Table 1 shows the results.

<Measurement of sound absorption at normal incidence>
The heat insulating sound absorbing material was cut by an automatic hot wire cutting machine so as to have a diameter of 29 to 28.5 mm to prepare a measurement sample. Based on ASTM E1050 (ISO10534-2), the normal incidence sound absorption coefficient of the surface where the non-through hole was formed was measured in a measurement frequency range of 500 to 6400 Hz using a small tube (diameter of 29 mm).

<Thermal conductivity measurement>
The thermal conductivity was measured by a method according to JIS A 1412-2: 1999.

{Examples 2 to 13, Comparative Examples 1 to 9}
Using the foamed board shown in Table 1, a heat insulating sound absorbing material was produced in the same manner as in Example 1 except that the compression strain and the hole diameter and number of non-through holes were changed as shown in Table 1. The obtained heat insulating sound absorbing material was evaluated in the same manner as in Example 1. Table 1 shows the results.

  From Table 1, it can be seen that if the area ratio of the non-through holes is the same, the higher the compressive strain rate, the larger the maximum value of the sound absorption coefficient and the smaller the thermal conductivity. Further, the thermal conductivity of the heat insulating sound absorbing material and the thermal conductivity of the resin foam having the same compression strain without non-through holes are about 0.1 (mW / mK), and are within 0.5%. Error category.

Claims (10)

  A heat-insulating sound-absorbing material obtained by compressing a resin foam and having a plurality of non-through holes on at least one surface.   The heat insulating sound-absorbing material according to claim 1, wherein a compression strain is 10% or more and 50% or less.   The heat insulating and sound absorbing material according to claim 1 or 2, wherein a ratio of an opening area of the non-through hole to an area of a surface having the non-through hole is 50% or less.   The heat insulation according to any one of claims 1 to 3, wherein a maximum value of a normal incident sound absorption coefficient of the surface having the non-through hole in a frequency range of 500 Hz or more and 6400 Hz or less is 40% or more. Sound absorbing material.   The thermal insulation according to any one of claims 1 to 4, wherein a thermal conductivity is substantially the same as a thermal conductivity of the compressed resin foam having no non-through holes. Sound absorbing material.   The heat insulating sound-absorbing material according to any one of claims 1 to 5, wherein the resin foam is a styrene-based resin foam.   The heat-insulating sound-absorbing material according to any one of claims 1 to 6, wherein the heat-absorbing sound-absorbing material is formed by compressing a plate-shaped resin foam to have a plate shape.   The heat insulating sound absorbing material according to any one of claims 1 to 7 is laminated, and each of the heat insulating sound absorbing materials has a normal incidence on a surface having the non-through hole in a frequency range of 500 Hz or more and 6400 Hz or less. A heat-insulating sound-absorbing laminate characterized in that the frequency showing the maximum value of the sound absorption coefficient is different.   The heat insulating sound absorbing laminate according to claim 8, wherein the heat insulating sound absorbing material is stacked with the surface having the non-through hole facing in the same direction.   The method according to claim 1, further comprising: compressing the resin foam; and forming a plurality of non-through holes in at least one surface of the resin foam, in this order. 3. The method for producing a heat-insulating sound-absorbing material according to item 1.