JPS58221595A - Diaphragm for speaker - Google Patents

Abstract

PURPOSE:To obtain a diaphragm having flat frequency characteristics, high efficiency and high water resistance, by blending an olefin polymer to a 4-methylpentene. CONSTITUTION:A 4-methylpentene monomer has low fusing viscosity, inferior film forming property and molding property, and a glass transition temperature close to a room temperature. Therefore a large extent of change of elastic modulus and internal loss is produced by temperatures for said monomer. However both film forming and molding properties can be improved along with suppression of a large change of both elastic modulus and internal loss at glass transition temperature by blending the other olefine polymer to the 4-methylpentene. Furthermore a flaky material, hollow particles, an inorganic filler, whisker, inorganic fiber, wooden flour, etc. are mixed as reinforcing material to reduce a physical change at a glass transition temperature. This obtains a material of a high internal loss and high elastic modulus which is suited to the speaker cone paper.

Description

【発明の詳細な説明】 本発明はスピーカ用振動板に関し、特に周波数特性が平
坦でかつ高能率、広周波数帯域の耐水性に優れた熟成形
可能なスピーカ用振動板を提供することを目的とするも
のである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a speaker diaphragm, and in particular, an object of the present invention is to provide a speaker diaphragm that has flat frequency characteristics, high efficiency, excellent water resistance over a wide frequency range, and can be aged. It is something to do.

従来、スピーカ用振動板材料として紙コーンが多く使用
されてきだが、これは紙が低密度で適度の弾性率、内部
損失を有しているためである。これらの物性は音響特性
として能率、帯域１周波数特性の平坦性に大きく関係し
ている。しかし、紙コーンの場合は熱成形ができないだ
め一枚ずつコーン形状に抄造するか、円錐形に一旦はり
合せた抜水を十分吸収させた状態で熱金型で成形するか
の二つの方法が取られている。いずれの方法も職人技に
たよる所が多く、ロット間でのバラツキが大きい欠点が
あった。一方、紙に代わる材料としてアルミニウム、ベ
リリウム等の金属材料やポリプロピレン、ポリエチレン
等の高分子材料が使われ出したが、金属材料の場合は比
弾性率が高い反面、内部損失は極端に低い欠点を持ち鋭
い共振ピークを生じる。そのため主にツイータに使用さ
れている。また、高分子材料の場合は比弾性率２曲げ剛
性が低い反面、内部損失は高く成形性もすぐれているた
め、主にウーハに使用されている。Conventionally, paper cones have often been used as a material for speaker diaphragms because paper has a low density, appropriate elastic modulus, and internal loss. These physical properties are largely related to acoustic properties such as efficiency and flatness of band 1 frequency characteristics. However, in the case of paper cones, since thermoforming is not possible, there are two ways to do this: either they are made into cone shapes one by one, or they are pasted together into a cone shape and molded with a hot mold after absorbing enough water. It has been taken. Both methods rely heavily on craftsmanship and have the drawback of large variations between lots. On the other hand, metal materials such as aluminum and beryllium, and polymer materials such as polypropylene and polyethylene have begun to be used as materials to replace paper, but while metal materials have a high specific modulus of elasticity, they have the disadvantage of extremely low internal loss. This produces a sharp resonance peak. Therefore, it is mainly used for tweeters. In addition, in the case of polymer materials, although the specific elastic modulus 2 bending rigidity is low, the internal loss is high and the moldability is excellent, so they are mainly used for woofers.

本発明は高分子中で最も軽い４−メチルペンテンポリマ
を基材に用い内部損失が高く、かつ比弾性率２曲げ剛性
も高いフィルム振動板を提供するものである。４−メチ
ルペンテン単体は溶融粘度が低く成膜性や成形性が悪い
欠点をもち、又ガラス転移温度が室温付近（２９〜６０
℃）にあるため、温度による弾性率、内部損失の大きな
変化が生じ、音質変化をもたらす。４−メチルペンテン
に他のオレフィン系ポリマをブレンドすることにより成
膜性、成形性を改善し、ガラス転移温度における弾性率
、内部損失の急激な変化も押えられる。壕だ、この系に
強化材を加えることにより高弾性率化、およびガラス転
移温度での物性の急激な変化はさらに押えられる。The present invention provides a film diaphragm that uses 4-methylpentene polymer, which is the lightest among polymers, as a base material and has high internal loss and high specific modulus of elasticity 2 bending rigidity. 4-Methylpentene alone has the disadvantage of low melt viscosity and poor film forming and molding properties, and its glass transition temperature is around room temperature (29-60
℃), the elastic modulus and internal loss change significantly due to temperature, resulting in changes in sound quality. By blending 4-methylpentene with other olefinic polymers, film forming properties and moldability are improved, and rapid changes in elastic modulus and internal loss at the glass transition temperature can be suppressed. By adding a reinforcing material to this system, the modulus of elasticity can be increased and the rapid change in physical properties at the glass transition temperature can be further suppressed.

本発明でいう他のオレフィン系ポリマとはポリエチレン
、ポリプロピレン、ポリブチレンをいう。Other olefin polymers in the present invention include polyethylene, polypropylene, and polybutylene.

、４−メチルペンテンポリマはオレフィン系ポリマで無
極性であるだめ、極性を持つポリマとのプレが効果を持
つ。混合比としては、４−メチルペンテンの特長（低密
度、高融点等）を損なわない程度でかつ上記の欠点を補
なうことが要求されるだめ、４−メチルペンテン／他の
オレフィン系ポリマの体積比はｈ以上が望ましい。, 4-methylpentene polymer is an olefin polymer and is non-polar, so it is effective to combine it with a polar polymer. The mixing ratio of 4-methylpentene/other olefin polymer is required to maintain the characteristics of 4-methylpentene (low density, high melting point, etc.) and compensate for the above-mentioned drawbacks. The volume ratio is preferably h or more.

強化材としてはガラス転移温度での物性変化を押え、弾
性率を上げるために鱗片状物質、中空粒子、無機充填材
、ウィスカ、無機繊維、木粉が有効である。鱗片状物質
とは鱗状黒鉛、マイカガラスフレーク、魚のウロコ等を
いい、中空粒子とはガラスバルーン、シラスバルーン、
炭素バルーン等をいい、無機充填材とはタルク、炭酸カ
ルシウム、二酸化チタン、ベンガラ、炭素粉末等をいい
、ウィスカとは銅、鉄等の金属ウィスカ、炭化ケイ素、
アルミナ、黒鉛等の無機ウィスカ、ポリオキシメチレフ
等の高分子ウィスカをいい、無機繊維とは炭素繊維、ガ
ラス繊維、セラミック繊維、金属繊維等をいい、木粉と
は木材粉、もみがら粉等をいう。強化材の複合量として
は成膜性２弾性率。As reinforcing materials, scaly substances, hollow particles, inorganic fillers, whiskers, inorganic fibers, and wood flour are effective in suppressing changes in physical properties at the glass transition temperature and increasing elastic modulus. Scaly substances include scaly graphite, mica glass flakes, fish scales, etc., and hollow particles include glass balloons, shirasu balloons,
Carbon balloons, etc. are referred to, inorganic fillers include talc, calcium carbonate, titanium dioxide, red iron, carbon powder, etc., and whiskers include metal whiskers such as copper and iron, silicon carbide,
Inorganic whiskers such as alumina and graphite, and polymer whiskers such as polyoxymethyleff are referred to. Inorganic fibers include carbon fibers, glass fibers, ceramic fibers, metal fibers, etc., and wood flour refers to wood powder, rice husk powder, etc. means. The composite amount of reinforcing material is film formability 2 modulus of elasticity.

曲げ剛性の点から２０ｖｏ１％以下が望ましい。From the viewpoint of bending rigidity, 20vo1% or less is desirable.

このように４−メチルペンテンと他のオレフィン系ポリ
マとのブレンド物を暴利とすることにより、低密度、高
内部損失、高剛性の物性となり、音響特性としては周波
数特性が平坦でかつ高能率。By exploiting the blend of 4-methylpentene and other olefin polymers in this way, it has physical properties of low density, high internal loss, and high rigidity, and as for acoustic properties, it has a flat frequency response and high efficiency.

広周波数帯域化を図ることができる。又、従来のコーン
紙は耐水性、耐湿性および加工性に問題があるが、本発
明のフィルム振動板ではこれらの問題は全くない。さら
に４−メチルペンテンポリマは四塩化炭素に溶け、トル
エンにも少し膨潤するため、他のオレフィン系ポリマの
ような極端外接着性の悪さはなく、融点も２４６℃と高
く耐熱性にも優れている。A wide frequency band can be achieved. Further, conventional cone paper has problems with water resistance, moisture resistance, and processability, but the film diaphragm of the present invention does not have these problems at all. Furthermore, 4-methylpentene polymer dissolves in carbon tetrachloride and swells slightly in toluene, so it does not have extremely poor adhesive properties like other olefin polymers, and has a high melting point of 246°C and excellent heat resistance. There is.

以下に本発明の実施例について説明する。Examples of the present invention will be described below.

（実施例１） ４−メチルペンテンポリマ（三井石油化学■製ＴＰＸ）
８０ｖｏ１％とポリプロピレン（チッソ■製）２０ｖｏ
１％を二軸押出機を用いてブレンドレマスターペレット
を一旦作り、次にこのペレットを使用し押出機により厚
さ４００μｍのシートを作った。このシートの物性を表
１に示すが、ポリプロピレンと複合することにより密度
が高くなり弾性率も低下した反面、内部損失、成膜性お
よび成形性は大幅に改善され、真空成形が容易に行なえ
るようになった。ポリプロピレンの体積分率がｅ　ｅｓ
　ｖｏｌ　％以上になると接着性が極端に悪くなり、曲
げ剛性も低くなりすぎる欠点が現れだした。第１図の龜
に周波数特性を示すが、ポリプロピレン単体シート（第
１図のｂ参照）にくらべ高能率。(Example 1) 4-methylpentene polymer (TPX manufactured by Mitsui Petrochemicals)
80vo 1% and polypropylene (made by Chisso ■) 20vo
Blended remaster pellets were made using a twin-screw extruder using 1%, and then a sheet with a thickness of 400 μm was made using the extruder using the pellets. The physical properties of this sheet are shown in Table 1. Although the density increases and the elastic modulus decreases due to the composite with polypropylene, the internal loss, film formability, and formability are greatly improved, and vacuum forming can be easily performed. It became so. The volume fraction of polypropylene is
When the amount exceeds vol %, the adhesion becomes extremely poor and the bending rigidity becomes too low. The frequency characteristics are shown in Figure 1, and the efficiency is higher than that of a single polypropylene sheet (see b in Figure 1).

広帯域となった。It became broadband.

（実施例２） ４−メチルペンテンポリマ（三井石油化学■製Ｔ　Ｐ　
Ｘ　）　６０　ｖｏ１％とポリプロピレン（チッソ■製
）　３０　ｖｏ１％に強化材として３２６メツシユでふ
るいをかけたマイカ１０　ｖｏＡ’　％を二軸押出機を
用いて混合し−Ｈマスターペレットを作９、次にこのマ
スターベレットを使用し、押出機により厚さ４００μｍ
の複合シートを得た。このシートを遠赤外線で１分程度
加熱し、シートがたるみ出した時点で直径１６ｅｍのス
ピーカ用振動板形状に真中成形を行った。このシートの
物性を表１に示すが、ポリプロピレン単体のシートおよ
び実施例１のように強化材の入ってないシートに比べ高
比弾性率、高曲げ剛性となり、広帯域、低歪化を図るこ
とができる。成膜性は実施例１のシートの方が優れてい
た。マイカの量を１０ｖｏ１％と一定にしておき、４Ｊ
−メチルペンテンポリマとポリプロピレンとの混合比を
変えた場合の物性の変化を第２図〜第４図に示すが、ポ
リプロピレンの含有率が増えるにつれてガラス転移温度
での内部損失の鋭いピークは消え、その絶対値は上がり
、成形性も良くなる。一方、弾性率は低下し接着性も悪
くなる。４−メチルペンテンポリマ／ポリプロピレンの
体積化としては怖以上であることが望ましい。(Example 2) 4-Methylpentene polymer (Mitsui Petrochemical Co., Ltd. TP
X) 60 vo 1% and polypropylene (made by Chisso ■) 30 vo 1% and mica 10 voA' % sieved with 326 mesh as a reinforcing material were mixed using a twin screw extruder to make -H master pellets9. Using this master pellet, the thickness was 400 μm using an extruder.
A composite sheet was obtained. This sheet was heated with far infrared rays for about 1 minute, and when the sheet began to sag, it was molded in the middle into the shape of a speaker diaphragm with a diameter of 16 em. The physical properties of this sheet are shown in Table 1, and it has a higher specific modulus of elasticity and higher bending rigidity than a sheet made of polypropylene alone or a sheet without reinforcing material like Example 1, and can achieve a wide band and low distortion. can. The sheet of Example 1 had better film formability. Keeping the amount of mica constant at 10vo1%, 4J
- Figures 2 to 4 show changes in physical properties when the mixing ratio of methylpentene polymer and polypropylene is changed.As the content of polypropylene increases, the sharp peak of internal loss at the glass transition temperature disappears. Its absolute value increases and moldability also improves. On the other hand, the elastic modulus decreases and the adhesiveness also deteriorates. It is desirable that the volume of the 4-methylpentene polymer/polypropylene is greater than that.

ポリエチレン、ポリブチレジとの混合においても同様で
あった。又４−メチルペンテンポリマ／ポリプロピレン
の体積比を％と一定にしておき、マイカの含有率を順次
変えていった際の物性変化を第５図、第６図に示すが、
密度はマイカ含有率の増加に伴ない大きくなり、弾性率
も高くなる。曲げ剛性は２０　ｖｏ１％付近でピークを
もち、内部損失は低下していった。又、成膜性、成形性
鬼マイカの含有率が２０ｖｏ／％以上では極端に悪くな
った。他の強化材においても２Ｑｖｏ１％以上の含有率
では成膜性、成形性に破れ等の問題を生じた。The same thing happened when mixing with polyethylene and polybutylene resin. Figures 5 and 6 show the changes in physical properties when the mica content was sequentially changed while keeping the volume ratio of 4-methylpentene polymer/polypropylene constant at %.
As the mica content increases, the density increases and the elastic modulus also increases. The bending stiffness peaked around 20 vol%, and the internal loss decreased. Furthermore, film forming properties and moldability became extremely poor when the content of mica was 20 vo/% or more. Even in other reinforcing materials, problems such as tearing occurred in film formability and moldability when the content was 2Qvo1% or more.

（実施例３） ４−メチルペンテンポリマ（Ｔ　Ｐ　Ｘ　）　５０ｖｏ
ｄチ、高密度ポリエチレン（三井石油化学■製）３０ｖ
ｏＡ係、ガラスバルーン（粒径４ｏμｍ、カサ比重０　
、２５　）２０ｖｏ、ｊ？％を実施例２と同様の方法で
涜合し、厚さ４００μｍのシートを得た。このシートの
物性を表１に示すが、カサ比重が低いため曲げ剛性が大
きく、−低歪化が実現できた。(Example 3) 4-methylpentene polymer (TPX) 50vo
dchi, high-density polyethylene (manufactured by Mitsui Petrochemicals) 30v
oA section, glass balloon (particle size 4oμm, bulk specific gravity 0
,25)20vo,j? % in the same manner as in Example 2 to obtain a sheet with a thickness of 400 μm. The physical properties of this sheet are shown in Table 1. Since the bulk specific gravity is low, the bending rigidity is high, and low strain can be achieved.

（実施例４） ４−メチルペンテンポリマ（Ｔ　Ｐ　Ｘ　）　８６ｖｏ
Ｊチ、ポリブチレフ　１０　ｖｏ１％、タルク５　ＶＯ
１％（４０゜メツシュでふるいをかけたもの）を実施例
２と同じ方法で混合し、厚さ４００μｍのシートを得た
。(Example 4) 4-methylpentene polymer (TPX) 86vo
J Chi, Polybutyref 10 VO1%, Talc 5 VO
1% (sieved through a 40° mesh) was mixed in the same manner as in Example 2 to obtain a sheet with a thickness of 400 μm.

このシートの物性を表１に示すが、内部損失があがり、
又接着性の改善に効果があった。The physical properties of this sheet are shown in Table 1, and the internal loss increases.
It was also effective in improving adhesion.

（実施例６） ４−メチルペンテンポリマ（Ｔ　ＰＸ　）　３０ｖｏｌ
チ、ポリプロピレン６０ｖｏ／％、ポリオキシメチレン
ウィスカ（繊維長２００μｍ　）　１０ｖｏ／％を実施
例２と同じ方法で混合し、厚さ４００μｍのシートを得
た。このシートの物性を表１に示すが、高内部損失、高
比弾性率が得られ、成膜性もすぐれていた。又ガラス転
移温度での内部損失の鋭いピークも消去されていた。(Example 6) 4-methylpentene polymer (TPX) 30vol
H. 60 vo/% polypropylene and 10 vo/% polyoxymethylene whiskers (fiber length 200 μm) were mixed in the same manner as in Example 2 to obtain a sheet with a thickness of 400 μm. The physical properties of this sheet are shown in Table 1. High internal loss and high specific modulus of elasticity were obtained, and film formability was also excellent. Also, the sharp peak of internal loss at the glass transition temperature was also eliminated.

（実施例６） ４−メチルペンテンポリマ（Ｔ　Ｐ　Ｘ　）　９０ｖｏ
Ａ！％。(Example 6) 4-methylpentene polymer (TPX) 90vo
A! %.

ポリプロピレン５　ｖｏ７＋％、炭素繊維（東し、トレ
力　繊維長２％　）　ｓ　ＶＯＡ！％を実施例２と同じ
方法で混合し、厚さ４００μｍのシートを得た。このシ
ートの物性を表１に示すが、比弾性率１曲げ剛性が向上
し、接着性も改善された。Polypropylene 5 VO7+%, carbon fiber (Toshi, training force fiber length 2%) s VOA! % were mixed in the same manner as in Example 2 to obtain a sheet with a thickness of 400 μm. The physical properties of this sheet are shown in Table 1, and the specific elastic modulus 1 bending rigidity was improved and the adhesiveness was also improved.

（実施例７） ４−メチルペンテンポリマ（ＴＰ　Ｘ　’）　７０ｖｏ
／％。(Example 7) 4-methylpentene polymer (TPX') 70vo
/%.

ポリエチレン２０ｖｏ１％、もみがら粉（３００メツシ
ユでふるいをかけたもの）１０ｖｏＡ！％を実施例２と
同様の方法で混合し、厚さ４００μｍのシートを得た。20vo1% polyethylene, rice husk powder (sifted with 300 mesh) 10voA! % were mixed in the same manner as in Example 2 to obtain a sheet with a thickness of 400 μm.

このシートの物性を表１に示すが、密度が下がり、曲げ
剛性が高くなった。又接着性も改善された。The physical properties of this sheet are shown in Table 1, and the density decreased and the bending rigidity increased. Adhesion was also improved.

（以下余白） ルペンテンポリマに他のオレフィン系ポリマを混合する
ことによりシートの成膜性、成形性が大幅に改善され、
又、強化材の混入により弾性率が向上し接着性も改善さ
れた。(Left below) By mixing other olefin polymers with the lepentene polymer, the film forming properties and formability of the sheet are greatly improved.
In addition, the modulus of elasticity and adhesion were improved by incorporating the reinforcing material.

このように本発明のスピーカ用振動板は、内部゛損失が
大きく（紙の内部損失は０．０３５）、低密度で弾性率
も高い。そのため周波数特性が平坦でかつ高能率、広周
波数帯域の耐水性に優れ、しかも熱成形できる利点を有
するものである。As described above, the speaker diaphragm of the present invention has a large internal loss (the internal loss of paper is 0.035), a low density, and a high elastic modulus. Therefore, it has the advantage of having flat frequency characteristics, high efficiency, excellent water resistance over a wide frequency range, and can be thermoformed.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明のスピーカ用振動板と従来のポリプロピ
レン振動板の音圧周波数特性の比較図、第２図は同振動
板における４−メチルペンテンポリマとポリプロピレン
の混合比に対する弾性率１内部損失の変化曲線図、第３
図は同混合比に対する剥離強度の変化曲線図、第４図は
同混合比における温度−内部損失特性図、第５図は同振
動板におけるマイカ含有量に対する弾性率、内部損失の
変化曲線図、第６図は同振動板におけるマイカ含有量に
対する曲げ剛性の変化曲線図である。 代理人の氏名　弁理士　中　尾　敏　男　ほか１名第１
図 側旋数０４ｔ　） 第２図 ＩＩＦ種滉４−比（Ｎφ） 第３図 第４図 ３；ＩＬ凍（’ｔ）Fig. 1 is a comparison diagram of the sound pressure frequency characteristics of the speaker diaphragm of the present invention and a conventional polypropylene diaphragm, and Fig. 2 shows the elastic modulus 1 internal loss for the mixing ratio of 4-methylpentene polymer and polypropylene in the same diaphragm. Change curve diagram, 3rd
The figure is a change curve of peel strength with respect to the same mixing ratio, Figure 4 is a temperature-internal loss characteristic diagram with the same mixture ratio, and Figure 5 is a change curve of elastic modulus and internal loss with respect to mica content in the same diaphragm. FIG. 6 is a curve diagram of changes in bending rigidity with respect to mica content in the same diaphragm. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Diagram side rotation number 04t) Figure 2 IIF type 4-ratio (Nφ) Figure 3 Figure 4 Figure 3; IL freezing ('t)

Claims (1)

【特許請求の範囲】 （１）４−メチルペンテンポリマと他のオレフィン系ポ
リマとのブレンド物でなるスピーカ用子＋４去振動板。 　・ （２）他のオレフィン系ポリマに対する４−メチルペン
テンポリマの体積比が％以下の値であることを特徴とす
る特許請求の範囲第１項記載のスピーカ用振動板。 ＜３）４−メチルペンテンポリマと他のオレフィン系ポ
リマと他に２０ｖｏ７（％以下の強化材のブレンド物で
なるスピーカ用振動板。 （４）他のオレフィン系ポリマに対する４−メチルペン
テンポリマの体積比が％以下の値であることを特徴とす
る特許請求の範囲第３項記載めスピーカ用振動板。[Claims] (1) A diaphragm for a speaker made of a blend of 4-methylpentene polymer and other olefin polymer. (2) The speaker diaphragm according to claim 1, wherein the volume ratio of the 4-methylpentene polymer to other olefin polymers is % or less. <3) A speaker diaphragm made of a blend of 4-methylpentene polymer, another olefin polymer, and a reinforcing material of 20vo7 or less. (4) Volume of 4-methylpentene polymer relative to other olefin polymers 3. The speaker diaphragm according to claim 3, wherein the ratio is less than or equal to %.