JP2826314B2 - Sound absorbing material for home appliances - Google Patents

Sound absorbing material for home appliances

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Publication number
JP2826314B2
JP2826314B2 JP62196286A JP19628687A JP2826314B2 JP 2826314 B2 JP2826314 B2 JP 2826314B2 JP 62196286 A JP62196286 A JP 62196286A JP 19628687 A JP19628687 A JP 19628687A JP 2826314 B2 JP2826314 B2 JP 2826314B2
Authority
JP
Japan
Prior art keywords
sound
absorbing material
sound absorbing
thickness
frequency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP62196286A
Other languages
Japanese (ja)
Other versions
JPS6440894A (en
Inventor
雄助 菅野
郁夫 小林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
TAMAGAWA SENI KOGYOSHO KK
Original Assignee
TAMAGAWA SENI KOGYOSHO KK
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Application filed by TAMAGAWA SENI KOGYOSHO KK filed Critical TAMAGAWA SENI KOGYOSHO KK
Priority to JP62196286A priority Critical patent/JP2826314B2/en
Publication of JPS6440894A publication Critical patent/JPS6440894A/en
Application granted granted Critical
Publication of JP2826314B2 publication Critical patent/JP2826314B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は新規な家電製品用吸音材に関するものであ
る。更に詳しくは従来の吸音材で吸音されにくい低中周
波帯域の騒音を選択的に吸収し、軽くて薄い家電製品用
吸音材に関するものである。 〔従来の技術〕 従来吸音材として使用されているものは、吸音効果の
あるフェルトとか発泡ウレタン等をそのまま使用してい
る場合が多い。 遮音性が要求される場合は遮音機能を有するゴムとか
合成樹脂等を貼付して使用するのが通例であり、この場
合厚みも1mm以上のものが使用されている。 一般に騒音は可聴周波数全域に亘っており、吸音材で
騒音を吸収する場合、2,000ヘルツ以上の所謂高周波帯
域は吸音材の厚さが比較的薄く且つ吸音性能が劣ってい
ても吸音され易いが、2,000ヘルツ以下の低中周波帯域
を吸収するには吸音材の厚さを厚くする事によって対処
して来た。従来技術文献としては産業調査会出版部発行
「有機材料」153頁の「吸音材」の項を挙げる事ができ
る。この文献によれば吸音材の表面に吸音機能をもたな
いものを貼ると吸音材の機能がなくなると記載されてい
る。これが現在での技術水準である。 〔発明が解決しようとする問題点〕 近時、商品の軽薄短小化が望まれるため、商品に分厚
い吸音材を装着することが困難になって来た。吸音材を
薄くすると2,000ヘルツ以下の低中周波帯域の騒音は吸
音されきれずに残るケースが多い。遮音機能をもったゴ
ムとか合成樹脂を貼ったものは音を特定の方向に反射さ
せることはできても、解消する機能はなく、これ又抜本
策ではあり得ない。 従って、特に低中周波帯域の騒音の除去は困難な課題
として残されている。 一方で、我々の日常生活をとりまく家庭電化製品は増
える一方でこの家電製品からの生活騒音も、その増加と
共に、深刻な問題となった。例えば真夏時のクーラーの
コンプレッサーからの騒音も500〜2,000ヘルツの音が吸
音できずに残り、もはや放置できないものにまでなり家
電メーカーではその吸音対策に苦慮している。 家電メーカーでは、製品から発生する騒音は、騒音許
容基準曲線（NC曲線とも呼ぶ）に照合して騒音のうち許
容限以上の高い音圧を発している周波数を摘出して、こ
の辺の吸音対策をとるのが常套手段である。この許容さ
れない音圧の周波数はメーカーや製品によって異なるが
大体500〜2,000ヘルツの範囲内のものである。 このように吸音対策としては、特定の周波数だけの解
消策をとれればよいのであるが、従来の吸音材の吸音効
果は、第３図の如く、常に高周波帯域はよく吸音する
が、肝腎の500〜2,000ヘルツの帯域は、よほど厚手の吸
音材を入れないと吸音できない。これまでは止むなく50
0〜2,000ヘルツの低中周波帯域を吸音するため厚手の吸
音材を装着せざるを得なかった。これは製品を小型化
し、吸音材を薄くて軽いものにしたいという要求と矛盾
するという問題点を有していた。 本発明の目的は厚みの薄い吸音材で、従来吸音が困難
であった特定の周波数、特に500〜2,000ヘルツの範囲内
の低中周波帯域の音を選択的に吸収し得る新吸音材を提
供することにある。 〔問題点を解決するための手段〕 本発明者は特定の周波数のみを狙い撃ち的に吸音でき
る吸音材の開発に多年にわたり取り組んで来たが、音波
の原理原則に立脚し、前記の問題点を解決するために多
くの実験にもとずく研究の結果通常の吸音材の表面に被
膜を形成する二層構造とすることによって薄い吸音材で
も容易に500〜2,000ヘルツの低中周波帯域内の音を吸音
できることを見出して本発明を完成した。 すなわち本発明はフェルト、ポリウレタンフォームよ
りなる群より選ばれた少なくとも１種の吸音材の音波入
射側の表面に、一部の音波を反射するゴム、樹脂、重量
物セラミック粉の粉体を樹脂、ゴムに分散させたものか
らなる群より選んだ少なくとも１種の物質の被膜で、厚
さが0.02mm〜0.5mmの範囲で、比重1.8以上の被膜を施し
てなる家電製品用吸音材である。 音波が物体に衝突した場合、その物体の固有振動数以
上の周波数の音波は反射し、固有振動数以下の音波は伝
播するという事実に着目した。即ち吸音材の表面に特定
周波数以上の音波を反射する物体を施しておけば、吸音
材には特定周波数以下の音波のみが伝播する。 通常の吸音材の表面にこの特定周波数以下の音波のみ
伝播する薄層を施したところ、この吸音材の吸音性能が
意外にも、従前の吸音性能とは全く異なる事を見出し
た。 一般に吸音材に入射した音波は、吸音材の細かい間隙
を伝わっていく間に界壁で粘性抵抗等が生じ、音圧は吸
音材の厚さとともに低下してゆくことはハーゲン−ポア
ゼイユの法則で既に知られている。 ハーゲン−ポアゼイユの法則は ΔP:音圧降下（mmAq） μ ：流体の粘性係数（Kg/SM） r ：間隙（ｍ） I ：吸音材の厚さ（ｍ） V ：流速（m/s）とすると ΔＰ＝８μ×I/r2×Ｖ（mmAq） この法則から、音波の周波数（空気の振動速度）によ
って、高周波側ほど音圧が低下し易いことが分る。第３
図よりもこの傾向は明らかである。（産業調査会出版部
発行「有機材料」153頁による。）第３図によれば公知
の厚さの異なるポリウレタンフォーム（密度0.024g/c
m3）の垂直入射吸音率曲線で、10mm→25mm→50mmと厚さ
が厚くなるに従って吸音率は向上する。又音波の中で高
周波側ほど吸音され易い。反面低中周波域では比較的薄
いウレタンでは吸音されにくい。 然るに本発明では従来の吸音材の表面に一部の音波を
反射する被膜を施すと、吸音材の厚さが従前と同一であ
っても、驚くべきことに低中周波帯域の吸音が従前とは
様変りに向上し、これまで吸音できなかった低中周波数
帯域のみを見事に吸音することが可能になったのであ
る。 第１図は本発明の新吸音材の断面を説明的に示した図
である。この新吸音材の吸音効果の改善の様子を第２図
で説明する。曲線（Ａ）は従来の10mm厚，嵩比重0.08の
フェルトの吸音率曲線である（JISA1405管内法による測
定）。曲線（Ｂ）は本発明の吸音材の吸音率曲線であ
る。この吸音材は曲線（Ａ）と同一のフェルトの音波入
射側表面に銅カラミ（銅精煉の際に副生するスラグ）を
微細に粉砕し、溶剤で溶解した樹脂液で練ってフェルト
の表面に0.08mmの厚さに塗布して乾燥したものである。 本発明の新吸音材による曲線（Ｂ）は800ヘルツ〜1,6
00ヘルツの中周波帯域の吸音率を向上させている。特筆
されるべき事は本発明の吸音材は従来の吸音材と比べて
吸音率曲線の形が全く変る事である。この吸音率向上は
極めて顕著で驚異的なものといえる。この場合、被膜は
音波の入射側の面のみに被膜状に処理を施せばよい。 銅カラミ以上に質量が大きく、弾性率が小さく、内部
摩擦の大きい被膜をより厚く塗布すると、反射する音波
の周波数はより低周波側にまで移行し、従って低周波側
の吸音が可能になる。 しかしこれにも限度があり、あまり厚く且つ質量の大
きい被膜を表面に施すと、全周波が遮音され、所謂遮音
材になってしまう。 発明者の多くの実験の結果、被膜の厚さは0.5mmが限
界である。この0.5mm以下の厚さであれば、ゴムや樹脂
系のものもその効果を発揮する。銅や鉄その他の金属の
精練時のスラグのような重量物の粉体を樹脂溶液と練っ
て、直接吸音材に塗布するか、又は一旦不織布に塗布し
て、これをフェルトにラミネートしてもよい。またセラ
ミック粉を樹脂液と練って同様に塗布してもよい。いず
れの場合も、乾燥した状態で厚さ0.5mm程度が上限とな
る。厚さ0.5mmを超えると、表面で反射される音波エネ
ルギーが大きくなり、遮音材に近づき、吸音材として機
能しなくなる。 被膜の厚さの下限については、被膜が薄ければ、音波
の反射機能が小さくなっしまうし、厳密な厚さの管理が
困難になるので、当然限度があり、発明者の実験では0.
02mm程度がその下限である。 即ちフェルト、発泡ウレタン等の通常の吸音材の音波
入射側表面に施す被膜としては厚さ0.02〜0.5mmの範囲
が好ましい。 厚さと同様に本発明に於ける被膜の質量を規定する比
重は重要な要素である。あくまでも厚さを前記範囲とし
て、被膜の質量は小さすぎては音波の反射効果がなくな
る。この質量を規定する比重としては実験の結果1.8以
上であることが必要である。上限は、被膜厚みを薄くす
ることによって、高比重のものも使用できるが、実用的
厚みと実際に吸音を要するピークとから４以下が好まし
い。 被膜の比重が1.8未満であると、被膜を施した効果が
なく、従来の吸音材と同じ吸音性能となってしまう。 本発明ではこのように吸音材の音波入射側表面に施す
薄層の被膜としてはゴム、樹脂類、重量物の粉体を樹脂
等に分散させたもの、セラミック質を樹脂類に分散させ
たもの等を含むが、金属板は含まない。金属板では全音
波が反射されてしまう。これは一見完全遮音でよいよう
に思われるが、特に低中周波帯域の音波のエネルギーは
吸音材における如く吸収消滅せず、機器内部の種々の固
有振動数の部品と共鳴を起し、様々な障害を引き起こし
たり、実際には騒音発生源を完全密閉状態にする事は不
可能でわずかの間隙から騒音が洩れてくることになる。
本発明吸音材では2,000ヘルツ以上の高周波帯域の音を
反射させてしまい、この帯域の吸音率はむしろ従来の吸
音材より若干下まわっているが、この帯域の音はエネル
ギーが小さく反射をくり返すうちに容易に自然減衰によ
って音は消滅し、この場合の実害はないのである。 〔実施例〕 以下に実施例によって、本発明を具体的に説明する
が、本発明はこの実施例によって何等限定されるもので
はない。 第１表によって明らかなように、通常の吸音材の表面
に比重1.8以上で0.02〜0.5mmの表面被膜を施すと、通常
の吸音材では吸音し難い500〜2,000ヘルツの低中周波数
帯域の音波を吸収し得るばかりでなく、表面被膜の厚さ
とか比重を制御することによって吸収のピーク周波数を
変えることができ、特定の周波数の音を狙い撃ち的に吸
収消音することができる。 第２表の比較例より明らかなようにこの表面被膜も、
厚みを余り厚くしたり、質量（比重）を余り大きくする
と全周波帯域を反射するようになって、所期の目的を達
しない。 又同じ厚み範囲でも、比重が1.8より小さいものでは
効果が認められない。 〔発明の効果〕 本発明の新吸音材によれば、従来の家電製品用吸音材
で厚さが薄い場合には、吸音が困難であった500〜2,000
ヘルツの低中周波帯域の騒音を効率よく吸音できるばか
りでなく、製品により特有の特定周波数を中心とした騒
音の音圧を狙い撃ち的に吸音消滅させ得る。この結果、
家庭電化製品等の小型軽量化且つ消音化に寄与でき、改
良手段としても、コストが大きくかかるものではないの
で実用的価値は極めて大きい。The present invention relates to a novel sound absorbing material for home electric appliances. More specifically, the present invention relates to a light and thin sound absorbing material for home appliances, which selectively absorbs noise in a low-to-medium frequency band which is hardly absorbed by a conventional sound absorbing material. [Related Art] Conventionally, as a sound absorbing material, a felt or a urethane foam having a sound absorbing effect is often used as it is. When sound insulation is required, it is customary to attach a rubber or synthetic resin having a sound insulation function and use it. In this case, a material having a thickness of 1 mm or more is used. Generally, noise is over the entire audible frequency range, and when absorbing noise with a sound-absorbing material, the so-called high-frequency band of 2,000 Hz or more is easily absorbed even if the thickness of the sound-absorbing material is relatively thin and the sound absorbing performance is inferior, In order to absorb the low and middle frequency bands below 2,000 Hz, the thickness of the sound absorbing material has been increased. Examples of the prior art literature include “Sound Absorbing Material” on page 153 “Organic Materials” published by the Industrial Research Institute Publishing Division. According to this document, it is described that if a material having no sound absorbing function is attached to the surface of the sound absorbing material, the function of the sound absorbing material is lost. This is the current state of the art. [Problems to be Solved by the Invention] Recently, since it is desired to reduce the size and weight of products, it has become difficult to attach a thick sound absorbing material to the products. If the sound absorbing material is made thinner, the noise in the low and medium frequency bands below 2,000 Hertz often remains unabsorbed. A rubber or synthetic resin with sound insulation function can reflect sound in a specific direction, but has no function to cancel it, and this is not a drastic measure. Therefore, the removal of noise particularly in the low and medium frequency bands remains as a difficult task. On the other hand, while the number of home appliances surrounding our daily lives has increased, the noise from home appliances has also become a serious problem with the increase. For example, the noise from the compressor of the cooler during the summer is 500 to 2,000 Hz, which cannot be absorbed and can no longer be left unattended, and home appliance manufacturers are struggling with sound absorption measures. Home appliance manufacturers compare the noise generated from products with the noise tolerance standard curve (also called the NC curve), extract the frequency of the noise that emits a sound pressure that is higher than the allowable limit, and take measures to absorb sound in this area. It is common practice to take. The frequency of this unacceptable sound pressure varies between manufacturers and products, but is generally in the range of 500-2,000 Hertz. Thus, as a sound absorbing measure, it is only necessary to take measures to eliminate only a specific frequency. However, as shown in FIG. 3, the sound absorbing effect of the conventional sound absorbing material always absorbs the high frequency band well, but the 500 The band of ~ 2,000 Hz can not absorb sound unless thick sound absorbing material is inserted. Up to now 50
In order to absorb the low to mid-frequency band of 0 to 2,000 Hz, thick sound absorbing materials had to be installed. This has a problem that it is inconsistent with the demand for downsizing the product and making the sound absorbing material thinner and lighter. An object of the present invention is to provide a new sound absorbing material which is a thin sound absorbing material capable of selectively absorbing a specific frequency which has conventionally been difficult to absorb sound, particularly a low to middle frequency band within a range of 500 to 2,000 Hz. Is to do. [Means for Solving the Problems] The present inventor has been working for many years on the development of a sound absorbing material capable of aiming and absorbing sound only at a specific frequency. The results of research based on many experiments to solve the problem of sound in the low-mid frequency band of 500 to 2,000 Hz easily even with thin sound absorbing material by using a two-layer structure that forms a coating on the surface of ordinary sound absorbing material The present inventors have found that sound can be absorbed and completed the present invention. That is, the present invention relates to a surface of the at least one kind of sound absorbing material selected from the group consisting of a felt and a polyurethane foam, on the surface on the sound wave incident side, a rubber, a resin, and a powder of a heavy ceramic powder, A sound-absorbing material for home appliances, comprising a coating of at least one substance selected from the group consisting of rubber dispersed components and having a thickness of 0.02 mm to 0.5 mm and a specific gravity of 1.8 or more. Attention was paid to the fact that when a sound wave collides with an object, the sound wave having a frequency higher than the natural frequency of the object is reflected, and the sound wave having a frequency lower than the natural frequency propagates. That is, if an object that reflects sound waves of a specific frequency or more is provided on the surface of the sound absorbing material, only sound waves of a specific frequency or less propagate to the sound absorbing material. When a thin layer that propagates only sound waves of a specific frequency or less is applied to the surface of a normal sound absorbing material, it has been found that the sound absorbing performance of the sound absorbing material is completely different from the conventional sound absorbing performance. In general, sound waves incident on the sound absorbing material generate viscous resistance at the boundary wall while traveling through the fine gap of the sound absorbing material, and the sound pressure decreases with the thickness of the sound absorbing material according to Hagen-Poiseuille's law. Already known. Hagen-Poiseuille's law is ΔP: sound pressure drop (mmAq) μ: viscosity coefficient of fluid (Kg / SM) r: gap (m) I: thickness of sound absorbing material (m) V: flow velocity (m / s) Then, ΔP = 8 μ × I / r 2 × V (mmAq) From this rule, it can be seen that the sound pressure is more likely to decrease on the higher frequency side due to the frequency of the sound wave (air vibration speed). Third
This tendency is clearer than the figure. (Based on page 153 of "Organic Materials" published by the Industrial Research Institute Press.) According to FIG. 3, known polyurethane foams having different thicknesses (density: 0.024 g / c)
In the normal incidence sound absorption coefficient curve of m 3 ), the sound absorption coefficient increases as the thickness increases from 10 mm to 25 mm to 50 mm. The higher the frequency side of the sound wave, the easier the sound is absorbed. On the other hand, in a low-mid frequency region, relatively thin urethane is not easily absorbed. However, in the present invention, if a coating that reflects a part of the sound wave is applied to the surface of the conventional sound absorbing material, even if the thickness of the sound absorbing material is the same as before, surprisingly, the sound absorption in the low and middle frequency band is the same as before. Has improved dramatically, and it has become possible to perfectly absorb only low and middle frequency bands, which previously could not be absorbed. FIG. 1 is a view illustratively showing a cross section of a new sound absorbing material of the present invention. FIG. 2 shows how the sound absorbing effect of the new sound absorbing material is improved. Curve (A) is a conventional sound absorption coefficient curve of a felt having a thickness of 10 mm and a specific gravity of 0.08 (measured by the in-tube method of JIS A1405). Curve (B) is a sound absorption coefficient curve of the sound absorbing material of the present invention. This sound absorbing material finely grinds copper karam (slag by-produced during copper refining) on the sound wave incident side surface of the same felt as the curve (A), kneads it with a resin solution dissolved in a solvent, and puts it on the felt surface. It was applied to a thickness of 0.08 mm and dried. The curve (B) of the new sound absorbing material of the present invention is 800 Hz to 1,6.
The sound absorption coefficient in the middle frequency band of 00 Hz is improved. It should be noted that the sound absorbing material of the present invention has a completely different shape of the sound absorbing coefficient curve as compared with the conventional sound absorbing material. This improvement in sound absorption is extremely remarkable and surprising. In this case, the film may be processed into a film only on the surface on the incident side of the sound wave. When a coating having a larger mass, a lower elastic modulus, and a higher internal friction than a copper lump is applied thicker, the frequency of the reflected sound wave shifts to a lower frequency side, so that sound absorption on the lower frequency side becomes possible. However, there is a limit to this, and if a coating that is too thick and has a large mass is applied to the surface, all frequencies will be sound-insulated, resulting in a so-called sound insulating material. As a result of many experiments by the inventors, the thickness of the coating is limited to 0.5 mm. If the thickness is 0.5 mm or less, a rubber or resin-based material exhibits the effect. Even if a heavy powder such as slag at the time of refining copper or iron or other metal is kneaded with a resin solution and directly applied to a sound absorbing material, or once applied to a non-woven fabric, it can be laminated to a felt. Good. Alternatively, the ceramic powder may be kneaded with the resin liquid and applied in the same manner. In any case, the upper limit is about 0.5 mm in a dry state. If the thickness exceeds 0.5 mm, the sound wave energy reflected on the surface increases, approaches the sound insulating material, and does not function as a sound absorbing material. Regarding the lower limit of the thickness of the coating, if the coating is thin, the sound wave reflection function is reduced, and it becomes difficult to control the thickness strictly.Therefore, there is a limit.
The lower limit is about 02 mm. That is, the thickness of the coating applied to the sound incident side surface of a normal sound absorbing material such as felt or urethane foam is preferably in the range of 0.02 to 0.5 mm. The specific gravity defining the mass of the coating in the present invention as well as the thickness is an important factor. When the thickness is within the above range, if the weight of the coating is too small, the effect of reflecting sound waves is lost. It is necessary that the specific gravity defining this mass be 1.8 or more as a result of the experiment. The upper limit may be one having a high specific gravity by reducing the thickness of the coating, but is preferably 4 or less from the practical thickness and the peak that actually requires sound absorption. If the specific gravity of the coating is less than 1.8, there is no effect of applying the coating, and the same sound absorbing performance as the conventional sound absorbing material will be obtained. In the present invention, as the thin film coating applied to the sound wave incident side surface of the sound absorbing material, rubber, resin, a powder of a heavy material dispersed in a resin or the like, or a ceramic in a resin is dispersed. Etc., but not a metal plate. A metal plate reflects all sound waves. At first glance, it seems that complete sound insulation is sufficient, but in particular, the energy of sound waves in the low and middle frequency bands does not absorb and disappear as in the sound absorbing material, causing resonance with various natural frequency components inside the device, and various It is impossible to cause trouble or to make the noise source completely closed, and noise will leak from a small gap.
The sound absorbing material of the present invention reflects sound in a high frequency band of 2,000 Hz or more, and the sound absorbing rate in this band is slightly lower than that of the conventional sound absorbing material, but the sound in this band has low energy and repeats reflection. The sound is easily extinguished by natural decay, and there is no real harm in this case. EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these examples. As is clear from Table 1, when a surface coating of 0.02 to 0.5 mm with a specific gravity of 1.8 or more is applied to the surface of a normal sound absorbing material, a sound wave in a low to medium frequency band of 500 to 2,000 Hz, which is difficult to absorb with the normal sound absorbing material. In addition to absorbing the sound, the peak frequency of the absorption can be changed by controlling the thickness and specific gravity of the surface coating, so that the sound of a specific frequency can be aimed and absorbed and silenced. As is clear from the comparative example in Table 2, this surface coating also
If the thickness is too large or the mass (specific gravity) is too large, the entire frequency band is reflected, and the intended purpose is not achieved. Even in the same thickness range, no effect is recognized if the specific gravity is smaller than 1.8. [Effects of the Invention] According to the new sound-absorbing material of the present invention, when the thickness of the conventional sound-absorbing material for home electric appliances is small, it is difficult to absorb sound from 500 to 2,000.
Not only can it efficiently absorb noise in the low and middle frequency bands of Hertz, but also can attenuate the sound pressure of noise centered on a specific frequency specific to the product by aiming. As a result,
It can contribute to the reduction in size and weight of household electric appliances and noise reduction and does not require much cost as an improvement means, so that its practical value is extremely large.

【図面の簡単な説明】 第１図は本発明の家電製品用吸音材の断面の説明図であ
る。 第２図は本発明の吸音材の吸音効果の改善を示した図で
ある。 第３図は従来公知の吸音材の厚みを変えた吸音率を示し
た図である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view of a cross section of a sound absorbing material for home electric appliances of the present invention. FIG. 2 is a diagram showing the improvement of the sound absorbing effect of the sound absorbing material of the present invention. FIG. 3 is a diagram showing the sound absorption coefficient when the thickness of a conventionally known sound absorbing material is changed.

Claims (1)

(57)【特許請求の範囲】 １．フェルト、ポリウレタンフォームよりなる群より選
ばれた少なくとも１種の吸音材の音波入射側の表面に、
一部の音波を反射するゴム、樹脂、重量物やセラミック
粉の粉体を樹脂、ゴムに分散させたものからなる群より
選んだ少なくとも１種の物質の被膜で、厚さが0.02mm〜
0.5mmの範囲で、比重1.8以上の被膜を施してなる家電製
品用吸音材。(57) [Claims] Felt, at least one type of sound absorbing material selected from the group consisting of polyurethane foam, on the surface on the sound wave incident side,
A film of at least one substance selected from the group consisting of rubber, resin, and heavy or ceramic powder that reflects some sound waves dispersed in resin or rubber.
A sound-absorbing material for home appliances with a coating with a specific gravity of 1.8 or more within a range of 0.5 mm.
JP62196286A 1987-08-07 1987-08-07 Sound absorbing material for home appliances Expired - Fee Related JP2826314B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62196286A JP2826314B2 (en) 1987-08-07 1987-08-07 Sound absorbing material for home appliances

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62196286A JP2826314B2 (en) 1987-08-07 1987-08-07 Sound absorbing material for home appliances

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JPS6440894A JPS6440894A (en) 1989-02-13
JP2826314B2 true JP2826314B2 (en) 1998-11-18

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JP (1) JP2826314B2 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2802759B1 (en) * 1999-12-16 2002-02-15 Pierre Fontaine METHOD FOR MANUFACTURING SURFACE MECHANICAL ABSORBENT MATERIAL, SURFACE MECHANICAL ABSORBENT MATERIAL AND ELECTROACOUSTIC TRANSDUCER THUS OBTAINED
JP6137783B2 (en) * 2012-05-23 2017-05-31 株式会社イノアックコーポレーション Sound insulation material and manufacturing method thereof

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5879891A (en) * 1981-11-05 1983-05-13 三菱電機株式会社 Sound absorbing material
JPS58132291A (en) * 1982-01-29 1983-08-06 三菱電機株式会社 Sound absorbing material
JPS61194499A (en) * 1985-02-25 1986-08-28 光洋産業株式会社 Felt sound absorbing structural body
JPS62896U (en) * 1985-06-19 1987-01-07

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